92 results on '"Peter, Sieg"'
Search Results
2. Double Positivity for HPV DNA/P16INK4aDoes Not Influence Survival of Patients With Oral Squamous Cell Carcinoma
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M.P. Gebhard, Lars Tharun, Peter Sieg, Ubai Alsharif, Samer G. Hakim, Dirk Rades, and Marvin Hofmann
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Oncology ,Cancer Research ,medicine.medical_specialty ,Proportional hazards model ,business.industry ,virus diseases ,Cancer ,General Medicine ,In situ hybridization ,medicine.disease ,female genital diseases and pregnancy complications ,Confidence interval ,Vaccination ,Regimen ,Internal medicine ,medicine ,Immunohistochemistry ,Prospective cohort study ,business - Abstract
Background/aim We investigated the prevalence of human papillomavirus (HPV) in a prospective cohort of patients with squamous cell carcinoma of the oral cavity (OSCC) using both p16INK4a and HPV DNA, i.e., double positivity, as a definition criterion. Additionally, we examined the association of HPV with survival. Patients and methods Samples from 280 OSCC patients were analyzed for HPV-positivity using p16INK4a immunohistochemistry (IHC) and in situ hybridization (ISH)/LCD arrays, for HPV low and high-risk types. Only patients positive for both p16INK4a and HPV DNA were considered as HPV-positive. Survival probabilities and 95% confidence intervals were estimated using the Kaplan-Meier method. Cox proportional hazards models were used to assess HPV association with disease-free survival (DFS), cause-specific survival (CSS) and overall survival (OS) in a competing risks scenario. Results Specimen from 30 (10.7%) patients were p16+ and HPV DNA+, while 31 (11.0%) were either p16+ or HPV DNA+ only. OS probabilities at five years for HPV-positive and -negative groups were 50.9% (35.4%-73.1%) and 52.9% (47.0%-59.5%), respectively. HPV double positivity influenced neither OS, CSS nor DFS: HR=0.84 (0.43-1.63), 1.64 (0.76-3.54) and 1.13 (0.55-2.35), respectively. Conclusion In contrast to oropharyngeal cancer, the prevalence of HPV in OSCC is low and the presence of HPV does not influence survival outcomes. Hence, there is no evidence to support a parallel transfer of therapy regimen for HPV-positive OPC to OSCC, in terms of therapy de-escalation and/or vaccination.
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- 2021
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3. Resection of medial orbital tumours via lateral orbitotomy and minimally invasive microscopic, transconjunctival and pre-caruncular approaches
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Peter Sieg and Samer G. Hakim
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medicine.medical_specialty ,business.industry ,Surgical Flaps ,Resection ,Lateral orbitotomy ,Otorhinolaryngology ,medicine ,Humans ,Orbital Neoplasms ,Surgery ,Radiology ,Oral Surgery ,business ,Conjunctiva ,Orbit - Published
- 2022
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4. Heteromorphe panfaziale Hautneoplasie
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Lena Cohrs, Konstanze Holl-Ulrich, Mohamed Falougy, and Peter Sieg
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medicine.medical_specialty ,Plastic surgery ,Otorhinolaryngology ,business.industry ,General surgery ,medicine ,Oral and maxillofacial surgery ,Head and neck surgery ,business - Published
- 2021
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5. Clinical course and survival in patients with squamous cell carcinoma of the maxillary alveolus and hard palate: Results from a single-center prospective cohort
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Samer G. Hakim, Daniel Steller, Dirk Rades, Peter Sieg, and Ubai Alsharif
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Palate, Hard ,Oncology ,medicine.medical_specialty ,medicine.medical_treatment ,Single Center ,Disease-Free Survival ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Maxilla ,medicine ,Humans ,Prospective Studies ,Tooth Socket ,Stage (cooking) ,Prospective cohort study ,Survival analysis ,Neoplasm Staging ,Retrospective Studies ,business.industry ,Hazard ratio ,Neck dissection ,030206 dentistry ,Survival Rate ,Radiation therapy ,Otorhinolaryngology ,Lymphatic Metastasis ,030220 oncology & carcinogenesis ,Cohort ,Carcinoma, Squamous Cell ,Neck Dissection ,Surgery ,Neoplasm Recurrence, Local ,Oral Surgery ,business - Abstract
Objectives Operative management of squamous cell carcinoma of the maxillary alveolus and hard palate (MHSCC) is still a controversial issue, especially for cN0 cases. We report the survival outcomes in patients with MHSCC, including the rate of cervical occult metastasis for UICC stages I/II and survival after elective neck dissection (END). Methods 77 patients with primary MHSCC were followed-up from 2 months to 14.6 years within a prospectively obtained patient cohort. Factors influencing overall survival (OS), oral cancer-specific survival (OCSS) and disease-free survival (DFS) were assessed. We estimated survival probabilities using Kaplan–Meier survival analysis by histology and stage. We used Cox's proportional hazard regression model to estimate adjusted hazard ratios for OS, OCSS and DFS. Results Initially, 22 patients presented with stage I, 13 with stage 2, 11 patients with stage 3 and 31 with stage 4 tumors. The presence of nodal disease rose with increased tumor size. 66.2% were treated with surgery only, 26.0% received adjuvant radiotherapy, and 7.8% received primary radiotherapy. Median overall survival was 10.9 years, and survival probabilities at 2, 5 and 10 years were 68.2%, 61.1% and 61.1%, respectively. Five-year overall survival was 72.4% in the END group and 88.9% in the non-END group. Factors influencing OS, OCSS and DFS were tumor size, the presence of metastatic disease and positive resection margins. Conclusions MHSCC seems to show a better overall survival compared to OSCC of other locations and is less likely to develop regional and distant metastasis; END might not be necessary in early stage tumors.
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- 2020
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6. Double Positivity for HPV DNA/P16
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Ubai, Alsharif, Marvin, Hofmann, Maximilian, Gebhard, Lars, Tharun, Dirk, Rades, Peter, Sieg, and Samer G, Hakim
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Male ,Time Factors ,Squamous Cell Carcinoma of Head and Neck ,Papillomavirus Infections ,Alphapapillomavirus ,Middle Aged ,Immunohistochemistry ,Disease-Free Survival ,Human Papillomavirus DNA Tests ,Predictive Value of Tests ,Germany ,DNA, Viral ,Biomarkers, Tumor ,Prevalence ,Humans ,Female ,Mouth Neoplasms ,Cyclin-Dependent Kinase Inhibitor p16 ,In Situ Hybridization ,Aged - Abstract
We investigated the prevalence of human papillomavirus (HPV) in a prospective cohort of patients with squamous cell carcinoma of the oral cavity (OSCC) using both p16Samples from 280 OSCC patients were analyzed for HPV-positivity using p16Specimen from 30 (10.7%) patients were p16+ and HPV DNA+, while 31 (11.0%) were either p16+ or HPV DNA+ only. OS probabilities at five years for HPV-positive and -negative groups were 50.9% (35.4%-73.1%) and 52.9% (47.0%-59.5%), respectively. HPV double positivity influenced neither OS, CSS nor DFS: HR=0.84 (0.43-1.63), 1.64 (0.76-3.54) and 1.13 (0.55-2.35), respectively.In contrast to oropharyngeal cancer, the prevalence of HPV in OSCC is low and the presence of HPV does not influence survival outcomes. Hence, there is no evidence to support a parallel transfer of therapy regimen for HPV-positive OPC to OSCC, in terms of therapy de-escalation and/or vaccination.
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- 2021
7. Impact of stratified resection margin classification on local tumor control and survival in patients with oral squamous cell carcinoma
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Samer G. Hakim, Daniel Steller, Mohamed Falougy, Dirk Rades, Lars Tharun, Robert von Bialy, Peter Sieg, and Ubai Alsharif
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Male ,medicine.medical_specialty ,Margin (machine learning) ,Medicine ,Humans ,Basal cell ,In patient ,Prospective Studies ,Aged ,Retrospective Studies ,business.industry ,Hazard ratio ,Cancer ,Margins of Excision ,General Medicine ,Middle Aged ,Tumor control ,medicine.disease ,Prognosis ,Surgery ,Survival Rate ,Oncology ,Cohort ,Resection margin ,Carcinoma, Squamous Cell ,Female ,Mouth Neoplasms ,business ,Follow-Up Studies - Abstract
BACKGROUND Guidelines recommended for resection of oral cancer define a free margin of ≥5 mm as clear and safe (R0). This statement was questioned recently based on the assumption that different surgical margins may hold different risk categories. The aim of this study was to investigate the impact of stratification of the surgical margins on the survival outcome of patients with oral cancer. METHODS In a cohort of 753 patients, the hazard ratio for local recurrence-free survival (LRFS), overall survival (OS), and oral cancer-specific survival (OCSS) were estimated for R0 resection, the close margin of 1-4 mm, involved resection borders but with free frozen sections. Competing risk factors were considered in the statistical regression model. RESULTS One hundred seventy-three (23%) patients developed local recurrence and 316 (42%) died in the 5 follow-up years. There was a gradual improvement in the LRFS, OCSS, OS with the increase of clear margin. OS showed a similar tendency. CONCLUSION Not all patients with an R0cm status carry the same risk for impaired LRFS, OCSS, and OS. Their risk to develop recurrence is higher than those patients with R0 ≥5 mm but stratified risk management can be recommended according to the presented results.
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- 2021
8. Leukoplakia and Squamous Cell Carcinoma
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Samer George Hakim and Peter Sieg
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- 2021
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9. Radioprotective effect of lidocaine on neurotransmitter agonist-induced secretion in irradiated salivary glands.
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Yu-xiong Su, Geza A Benedek, Peter Sieg, Gui-qing Liao, Andreas Dendorfer, Birgit Meller, Dirk Rades, Matthias Klinger, and Samer G Hakim
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Medicine ,Science - Abstract
BACKGROUND: Previously we verified the radioprotective effect of lidocaine on the function and ultrastructure of salivary glands in rabbits. However, the underlying mechanism of lidocaine's radioprotective effect is unknown. We hypothesized that lidocaine, as a membrane stabilization agent, has a protective effect on intracellular neuroreceptor-mediated signaling and hence can help preserve the secretory function of salivary glands during radiotherapy. METHODS AND MATERIALS: Rabbits were irradiated with or without pretreatment with lidocaine before receiving fractionated radiation to a total dose of 35 Gy. Sialoscintigraphy and saliva total protein assay were performed before radiation and 1 week after the last radiation fraction. Isolated salivary gland acini were stimulated with either carbachol or adrenaline. Ca(2+) influx in response to the stimulation with these agonists was measured using laser scanning confocal microscopy. RESULTS: The uptake of activity and the excretion fraction of the parotid glands were significantly reduced after radiation, but lidocaine had a protective effect. Saliva total protein concentration was not altered after radiation. For isolated acini, Ca(2+) influx in response to stimulation with carbachol, but not adrenaline, was impaired after irradiation; lidocaine pretreatment attenuated this effect. CONCLUSIONS: Lidocaine has a radioprotective effect on the capacity of muscarinic agonist-induced water secretion in irradiated salivary glands.
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- 2013
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10. The impact of harvest length and detachment of the interosseous membrane on donor-site morbidity following free fibula flap surgery—a biomechanical experimental study
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Peter Sieg, Ali Shakery Tehrany, Robert Wendlandt, Thomas Trenkle, Hans-Christian Jacobsen, and Samer G. Hakim
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medicine.medical_specialty ,animal structures ,medicine.medical_treatment ,Osteotomy ,Free Tissue Flaps ,Tendons ,03 medical and health sciences ,0302 clinical medicine ,Free fibula ,medicine ,Humans ,Displacement (orthopedic surgery) ,Fibula ,Muscle, Skeletal ,Membranes ,Interosseous membrane ,business.industry ,musculoskeletal, neural, and ocular physiology ,030206 dentistry ,Fibula flap ,Phalanx ,musculoskeletal system ,Biomechanical Phenomena ,Surgery ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,Oral Surgery ,business ,Cadaveric spasm ,tissues ,Ankle Joint - Abstract
Purpose The fibula flap has been established for orofacial reconstruction following ablative surgery. Donor-site morbidity of the lower leg may be explained by the harvest technique and particularly by detachment of the M. extensor halluces longus (EHL) and M. extensor digitorum longus (EDL). Material and methods On cadaveric lower leg specimens, the tendons of the EHL and EDL were dissected at the proximal phalanges and loaded with corresponding weights. The average displacement of the muscle was evaluated during the harvesting procedure. Results Cumulative detachment of the interosseous membrane caused considerable displacement of the EHL but less impairment of the EDL. Segmental and cumulative osteotomy of the fibula implicated significant displacement of both EHL and EDL. Conclusion A recommendation can be given for cautious selection of osteotomy site of the fibula and for limited sacrifice of the fibula and adjacent attachments of the extensors to keep local-site morbidity at a minimum.
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- 2018
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11. Correlation of cone beam CT-derived bone density parameters with primary implant stability assessed by peak insertion torque and periotest in the maxilla
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Markus Ofer, Daniel Steller, Peter Sieg, Julia Glanz, and Samer G. Hakim
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Adult ,Bone density ,Mandible ,computer.software_genre ,Osseointegration ,Correlation ,Dental Prosthesis Retention ,03 medical and health sciences ,0302 clinical medicine ,Voxel ,Bone Density ,Hounsfield scale ,Maxilla ,Medicine ,Humans ,Aged ,Dental Implants ,business.industry ,Dental Implantation, Endosseous ,030206 dentistry ,Cone-Beam Computed Tomography ,Middle Aged ,Resonance frequency analysis ,Otorhinolaryngology ,Dental Prosthesis Design ,Torque ,030220 oncology & carcinogenesis ,Surgery ,Implant ,Oral Surgery ,Nuclear medicine ,business ,computer - Abstract
Purpose Primary implant stability is crucial to osseointegration. The aim of this study was to assess correlation of preoperative radiologic parameters with intraoperatively obtained biomechanical tests in the maxilla. Materials and methods A total of 259 implants were inserted in the maxilla of 99 patients. Cone-beam computed tomography (CBCT)-derived Hounsfield units (HU), voxel grey values and computed tomography mental index (CTMI) performed preoperatively were correlated with insertion torque and Periotest (obtained intraoperatively and 12 weeks later) to assess their prognostic value for primary implant stability. Results Voxel grey values and insertion torque showed a low correlation (r = 0.329, p = 1.055 × 10 − 7 ). Likewise, a low correlation was found between HU measured preoperatively and insertion torque as well as intraoperative Periotest values (r = 0.297, p = 4 × 10 − 6 and r = − 0.234, p = 4.35 × 10 − 4 , respectively). A moderate correlation could, however, be assessed between insertion torque and intraoperative as well as Periotest values 12 weeks later. (r = −0.555, p = 1.022 × 10 − 20 and −0.465. p = 1.150 × 10 − 13 ). On contrast, a high correlation was observed between the voxel grey values of CBCT and related HU (r = 0.710, p = 6.486 × 10 − 37 ) so that a conversion from grey values into HU could be suggested. According to regression analysis, an intraoperative negative Periotest value could be expected at an insertion torque of 40 N/cm upwards. Conclusion CBCT-based bone density parameters correlate with each other and allow conversion of grey scales into HU preoperatively. Both insertion torque and Periotest showed a significant correlation which enables regression analysis to predict implant stability for related insertion torque. On contrast, for HU the distribution curves do not allow a reliable assignment into certain Periotest values.
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- 2018
12. Wiederherstellung der HNO-Funktion durch plastisch-rekonstruktive Chirurgie
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Veronika Sofie Siebel, Holger Lauschke, Jens-Christian Deck, Janine Pishgah, Peter Sieg, Julia Zander, Dagmar Kerscher, Samer G. Hakim, Florian Sack, Sandra Hasenberg, Sonja Farajzadeh, Christiane Wedding, Quirine Laffree, Richard Stopa, Alexander Meetz, Christian Neuwirth, Nora Bacciocco, and S. Remmert
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business.industry ,Medicine ,business - Published
- 2018
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13. The current state of facial prosthetics – A multicenter analysis
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Daniel Rothamel, Alexander Schramm, Robert A. Mischkowski, Peter Sieg, Günter Lauer, Michael Rasse, Boris Mayer, Christopher Mohr, Christoph M. Ziegler, Andreas Neff, Michael Ehrenfeld, Oliver C. Thiele, Joachim E. Zöller, Siegmar Reinert, Martin Kunkel, Johannes Kuttenberger, Rudolf H. Reich, Frank Hölzle, Bernhard Frerich, Henning Schliephake, Hendrik Terheyden, Anton Dunsche, Martin Klein, P.A. Federspil, Jörg Wiltfang, Jörn Brom, Matthias Kreppel, Rainer Schmelzeisen, Alexander C. Kübler, Norbert R. Kübler, and Robert Sader
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Orthodontics ,business.industry ,Anaplastology ,Medizin ,Prosthesis Retention ,Prostheses and Implants ,Prosthesis Design ,Europe ,Implant fixation ,Fixation (surgical) ,Facial prosthesis ,Cochlear Implants ,Otorhinolaryngology ,Face ,Magnets ,Oral and maxillofacial surgery ,Humans ,Medicine ,Surgery ,Oral Surgery ,business ,Bone Plates - Abstract
Even though modern surgical techniques are dominating reconstructive facial procedures, the capability to use facial epitheses for reconstruction is still an important skill for the maxillofacial surgeon. We present an international multicenter analysis to clarify which techniques are used to fixate facial prostheses. We contacted all maxillofacial departments in Germany, Austria, Switzerland and Norway which were registered with the German society for oral and maxillofacial surgery (DGMKG). These centers were asked via electronical mail to provide information on the type of epithesis fixation systems currently in use. The return rate from 58 departments was 43.1% (n = 25). Overall, implant fixation was the preferred fixation system (92%). Plates were the second most common fixation technique (32%). No centers reported the standard use of non-invasive fixation techniques for permanent epithesis fixation. The main retention systems in use were magnets (24/25), other retention systems are used much less often. The current preferred fixation technique for facial epitheses consists of implant-based, magnet-fixated epitheses. For nasal prostheses, a plate-based, magnet-fixated system is often used.
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- 2015
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14. Masticatory rehabilitation following upper and lower jaw reconstruction using vascularised free fibula flap and enossal implants—19 years of experience with a comprehensive concept
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Thomas Trenkle, Samer G. Hakim, Hans-Christian Jacobsen, Peter Sieg, and Harald Kimmerle
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Dental Implants ,Orthognathic Surgical Procedures ,business.industry ,medicine.medical_treatment ,Mandible ,Soft tissue ,Dentistry ,Prosthesis ,Surgical Flaps ,Jaw ,Maxilla ,medicine ,Humans ,Mastication ,Implant ,Fibula ,business ,General Dentistry - Abstract
Conventional prosthesis is generally inapplicable following reconstruction with free fibula flaps (FFF) due to impaired bone and soft tissue conditions, and rehabilitation via enossal implants in FFF is relatively novel. This retrospective study aimed to document the surgical aspects of this option and to describe related supplementary procedures that can help optimise the definitive outcome. One hundred nineteen implants were inserted within FFFs in 37 patients (mean age 51.8 ± 10.6 years), who underwent ablative surgery of the maxilla (3) and mandible (34). In a cross-sectional study design with a follow-up period of 3–172 months, we analysed types and configurations of graft design, patterns of implant insertion and methods for prosthetic rehabilitation as well as primary stability and survival rate. Most patients underwent jaw reconstruction using a mono-barrel FFF (14 osseous and 18 osteocutaneous/osteomyocutaneous); three patients received double-barrel reconstruction of the mandible. Three patients with maxillary defects were reconstructed using mono-barrel grafts (one osteocutaneous and two prefabricated grafts). Pre-prosthetic procedures were required in 23 patients to optimise conditions in the peri-implant soft tissue. Iliac bone onlay graft was used in six patients to achieve appropriate vertical height in mono-barrel grafts. A total of 10 implants in eight patients (five irradiated) could not be loaded. All other implants showed stable osseous integration and satisfactory peri-implant soft tissue conditions. Masticatory rehabilitation can be achieved using enossal implants inserted in FFF. Special requirements can be met through selection of an appropriate graft configuration and optimal implant positioning. Supplementary pre-prosthetic procedures are usually required as they improve long-term survival. This overview provides a reliable and comprehensive algorithm for standard implant-borne rehabilitation of patients with fibula grafts.
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- 2014
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15. Unilateral cleft lip/nose repair using an equal bows /straight line advancement technique – A preliminary report and postoperative symmetry-based anthropometry
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Horst Heinrich Aschoff, Hans-Christian Jacobsen, Samer G. Hakim, and Peter Sieg
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Male ,Cephalometry ,Advancement technique ,Cleft Lip ,Nostril ,Dentistry ,Nose ,Patient Care Planning ,Cicatrix ,Cleft lip nose ,Nasal Cartilages ,Image Processing, Computer-Assisted ,medicine ,Humans ,Vermilion ,Child ,business.industry ,Mouth Mucosa ,Plastic Surgery Procedures ,Anthropometry ,Circumference ,Ridge (differential geometry) ,Lip ,medicine.anatomical_structure ,Otorhinolaryngology ,Case-Control Studies ,Female ,Surgery ,Oral Surgery ,Symmetry (geometry) ,business - Abstract
In the evolution of cleft lip repair there has been continuous attempt to minimize local trauma, improve lip and nasal appearance and, especially, prevent conspicuous scars. The surgical technique presented meets these criteria, resulting in an appropriate scar course in children with a specific philtral ridge shape. Postoperative digital anthropometry was performed in 18 patients who underwent unilateral cleft lip repair using the equal bows/straight line advancement technique and in matched healthy control individuals. Symmetry values were assessed for lip length, philtral ridge length, vermilion height, width of the alar base, nasocanthal length, circumference of the nostrils, nostril width and height in both cleft and control groups. Evaluation revealed no significant differences in the symmetry values between cleft patients and control group (lip length: p = 0.71, philtral ridge length: p = 0.52, vermilion height: p = 0.23, alar base width: p = 0.69, nasocanthal length: p = 0.25, nostril circumference: p = 0.17, nostril width: p = 0.34, nostril height: p = 0.33). Principles of cleft lip repair can be achieved using the described technique which provides adequate lip length and natural nasal appearance in patients with a parallel-shaped philtral ridge.
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- 2014
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16. RARE CRANIOFACIAL CLEFTS AND ENCEPHALOMENINGOCELES - CLINICAL FINDINGS AND FUNCTIONALLY ADAPTED SURGICAL MANAGEMENT DURING CHARITY MISSIONS
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Peter Sieg
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- 2016
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17. No correlation between two-dimensional measurements and three-dimensional configuration of the pharyngeal upper airway space in cone-beam computed tomography
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Marie Dorothée Abé-Nickler, Samer G. Hakim, Peter Sieg, and Samira Pörtner
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Adult ,Male ,Cone beam computed tomography ,Epiglottis ,Adolescent ,Correlation ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Imaging, Three-Dimensional ,Sex Factors ,Reference Values ,Medicine ,Humans ,Child ,Aged ,Aged, 80 and over ,Soft palate ,business.industry ,Age Factors ,030206 dentistry ,Anatomy ,Airway obstruction ,Cone-Beam Computed Tomography ,Middle Aged ,medicine.disease ,Vertebra ,medicine.anatomical_structure ,Otorhinolaryngology ,Pharynx ,Surgery ,Female ,Oral Surgery ,Posterior nasal spine ,Airway ,business ,030217 neurology & neurosurgery - Abstract
The aim of this study was to evaluate both the 2-dimensional (2D) and 3-dimensional (3D) configuration of the posterior airway space (PAS) in healthy 239 patients using cone-beam computed tomography (CBCT). In particular, we investigated the correlation between the 2D and 3D measurements in view of the potential impact on diagnosis of upper airway obstruction. The pharyngeal airway of each patient was studied at five levels: the level of the posterior nasal spine (PNS), the level of half-height of the PNS and the tip of the soft palate, the level of the tip of the soft palate, the level of the anterior-inferior point of the second vertebra, and at least the level of the top of the epiglottis. At each of these levels, the anterior-posterior dimension as well as the corresponding cross-sectional area was measured. Furthermore we measured the volume of the whole PAS between the first and the last level and compared it with the corresponding 2D values. Differences between genders and age effects were estimated in an analysis of covariance. P values.05 were considered significant. Linear models were fitted to find the optimal formula to calculate the area or volume from measured distances. Limits of agreement were calculated as 2 ± residual standard deviations. We generated normal 2D and 3D values of the PAS for a normal population. In regard to age, no significant differences were observed. Significant differences were assessed between healthy males and females; however no correlation was observed between the obtained measurements in 2D axial view and the corresponding cross-sectional areas and mean volume in 3D view. In summary, radiologic imaging is a helpful tool to evaluate the airway space in patients with OSAS. However, drawing conclusions from 2D PAS imaging to assess 3D PAS configuration is not reliable, since there is no sufficient correlation between posterior-anterior distances and the corresponding cross-sectional areas.
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- 2016
18. Long-term functional donor site morbidity after ulnar forearm flap harvest
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Cathrin Hansmann, Samer G. Hakim, Mete Dericioglu, Thomas Trenkle, Hans-Christian Jacobsen, and Peter Sieg
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Adult ,Male ,Microsurgery ,medicine.medical_specialty ,medicine.medical_treatment ,Time lag ,Transplant Donor Site ,Surgical Flaps ,Disability Evaluation ,Grip strength ,Postoperative Complications ,Forearm ,Surveys and Questionnaires ,Dash ,medicine ,Humans ,Aged ,Retrospective Studies ,Aged, 80 and over ,Hand function ,Hand Strength ,business.industry ,Head neck ,Forearm flap ,Middle Aged ,Plastic Surgery Procedures ,Surgery ,body regions ,medicine.anatomical_structure ,Otorhinolaryngology ,Physical therapy ,Female ,business - Abstract
Background The purpose of this study was to evaluate long-term functional donor site morbidity following ulnar forearm flap harvest taking both subjective and objective criteria into consideration. Methods In this retrospective analysis, 61 patients were evaluated for subjective and objective donor site morbidity 3 to 164 months after flap harvest, and the Disabilities of Arm, Shoulder, and Hand (DASH) questionnaire was used for evaluation of subjective hand function. Results There was no significant grip strength decrease in the donor limbs. Two patients developed severe functional impairment of the donor forearm. DASH scores displayed only minor functional impairment, with marginally improving scores with increasing time lag to surgery. Conclusions Low donor site morbidity was found after ulnar flap harvest. However, minor rates of patients suffered from severe impairment of the hand function. Therefore, we recommend using the nondominant limb and informing the patients in detail about the specific functional limitations. Head Neck, 2012
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- 2011
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19. Expression of Wnt-1, TGF-β and related cell–cell adhesion components following radiotherapy in salivary glands of patients with manifested radiogenic xerostomia
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Geza Attila Benedek, Alexander Berndt, Samer G. Hakim, Julika Ribbat, Peter Sieg, Thomas Trenkle, Petra Richter, Dirk Rades, Hartwig Kosmehl, and Hans Christian Jacobsen
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Male ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Cell ,Fluorescent Antibody Technique ,Wnt1 Protein ,Risk Assessment ,Xerostomia ,Salivary Glands ,stomatognathic system ,Stroma ,Transforming Growth Factor beta ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Cell adhesion ,Radiotherapy ,business.industry ,Head and neck cancer ,Transdifferentiation ,Wnt signaling pathway ,Radiotherapy Dosage ,Hematology ,Cadherins ,Prognosis ,Salivary Gland Neoplasms ,medicine.disease ,Immunohistochemistry ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,Radiation therapy ,Cross-Sectional Studies ,Treatment Outcome ,medicine.anatomical_structure ,Oncology ,Head and Neck Neoplasms ,Female ,business ,Cell Adhesion Molecules ,Transforming growth factor - Abstract
Background Radiation-induced xerostomia still represents a common symptom following radiotherapy of head and neck malignancies, which significantly impairs the patient’s quality of life. In this cross-sectional study, human salivary glands were investigated to assess the role of Wnt/β-catenin and TGF-β pathways in the pathogenic process of radiogenic impairment of salivary function. Methods Irradiated human salivary glands were investigated in patients with manifested xerostomia. Alteration of Wnt-1 and cell–cell adhesion was evaluated immunohistologically as well as changes in the expression of TGF-β were assessed in salivary gland tissue. Results We assessed two alteration patterns in which Wnt-1 expression represents one change along with up-regulation of β-catenin and E-cadherin in irradiated but viable acinar cells. Increased expression of tenascin-C was observed in sites of epithelial–mesenchymal interaction and loss of cell–cell adhesion was assessed in translocated epithelial cells in the stroma. Conclusion Increased transdifferentiation and remodeling of acinar structures was associated with decrease of viable acinar structures. The role of Wnt and TGF signaling may provide a potential therapeutic approach to prevent radiation-induced damage to salivary glands during radiotherapy for head and neck cancer.
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- 2011
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20. Ankyloglossia superior syndrome: case report and review of publications
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Peter Sieg and Henning Wieker
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Male ,Palate, Hard ,Fingers ,Glossopalatine ankylosis ,Tongue ,Tip of the tongue ,medicine ,Humans ,Deformed limbs ,Ankyloglossia ,Leg ,business.industry ,Syndrome ,Anatomy ,Cleft Palate ,stomatognathic diseases ,medicine.anatomical_structure ,Otorhinolaryngology ,Child, Preschool ,Surgery ,Hard palate ,Mouth Abnormalities ,Oral Surgery ,Gastrointestinal malformations ,business ,Hand Deformities, Congenital - Abstract
Ankyloglossia superior syndrome is a rare malformation that consists of a fibrous or osseous connection between the tip of the tongue and the hard palate, and additional congenital anomalies such as cleft palate, gastrointestinal malformations, and deformed limbs. We present the case of a 5-year-old boy with ankyloglossia superior syndrome that comprised the complete complex malformation. We reviewed previous publications and summarise the different theories of its genesis.
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- 2014
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21. Long-term evaluation of donor site morbidity after free fibula transfer
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Samer G. Hakim, Peter Sieg, Hans-Christian Jacobsen, and Ceylan Taner
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Foot Deformities ,Joint Instability ,Male ,musculoskeletal diseases ,Claw ,medicine.medical_specialty ,Functional impairment ,medicine.medical_treatment ,Surgical Flaps ,Postoperative Complications ,Free fibula ,Risk Factors ,Surgical Wound Dehiscence ,medicine ,Humans ,Surgical Wound Infection ,Longitudinal Studies ,Range of Motion, Articular ,Muscle, Skeletal ,Gait Disorders, Neurologic ,Wound Healing ,Bone Transplantation ,business.industry ,Skin Transplantation ,Toes ,Microsurgery ,Gait ,Surgery ,Individual risk factors ,Treatment Outcome ,Otorhinolaryngology ,Fibula ,Tissue and Organ Harvesting ,Canes ,Female ,Oral Surgery ,Range of motion ,business ,Ankle Joint ,Follow-Up Studies - Abstract
Our aim was to evaluate the long-term morbidity at the donor site after harvest of free fibular flaps. From a total of 165 patients, we were able to examine (not randomly) 62 donor regions in 57 patients (33 men and 24 women) 2-167 months (mean 45 months) after fibular transfer. Patients' individual risk factors and any disturbances of healing, and dysfunction of the toes, were recorded. The Kitaoka ankle-hindfoot score was used for evaluation of functional impairment. Thirteen donor regions displayed prolonged wound healing, eight of which needed revision of the wounds. Eight (14%) had abnormalities of gait. The median Kitaoka ankle-hindfoot score was 93 (range: 14-100). In 17 patients (27%) after a follow-up period of 4 months, hammer and claw toes and deficits in dorsal extension of the hallux were assessed. Thirty patients (48%) had sensory deficits of the calf and toes. Neither the risk factors recorded nor the factors that indicated disturbance of wound healing or deformities of the toe were significantly associated with the development of functional impairment. In more than three-quarters of the cases healing was uneventful, but in a small number the morbidity at the donor site was severe, forcing the patient to use walking aids. We were not able to identify any risk factors for the development of long-term malfunction.
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- 2010
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22. Innervation and Secretory Function of Transplanted Human Submandibular Salivary Glands
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Garrett, Guy H. Carpenter, Peter Sieg, I. Lauer, Collin, Gordon Proctor, Katherine L. Paterson, Gerd Geerling, and Samer G. Hakim
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Adult ,medicine.medical_specialty ,Sympathetic Nervous System ,Submandibular Gland ,Cholinergic Agonists ,Biology ,Atrophy ,stomatognathic system ,Internal medicine ,medicine ,Humans ,Secretion ,Radionuclide Imaging ,Neurotransmitter Agents ,Transplantation ,Vasomotor ,Salivary gland ,Parasympatholytics ,Middle Aged ,medicine.disease ,Submandibular gland ,Ganglion ,medicine.anatomical_structure ,Endocrinology ,Tears ,Carbachol ,Female ,Reinnervation - Abstract
Free submandibular gland autotransplantation is used to treat absolute tear deficiency. Although disconnected from any peripheral innervation, most transplants show increasing secretion for years. We have evaluated the secretory activity and autonomic innervation of such transplants. Secretory activity of glands in response to parasympatholytics and parasympathomimetics was evaluated by Schirmer's test and Technetium scintigraphy. Submandibular gland tissue specimens taken before and after transplantation were examined histologically. Relative hypersecretion during the first postoperative week suddenly decreased but then slowly increased during the first postoperative year. Hypersecretion was significantly reduced by parasympatholytics while carbachol rapidly increased secretion. Histology of transplanted glandular tissue showed parenchymal atrophy. Cholinesterase-positive nerves were abundant and in a similar distribution to normal with scattered positive ganglion cells. Adrenergic axons were fewer than normal and irregularly distributed. Early hypersecretion may be due to release of neurotransmitters from degenerating terminal axons. This is followed by a period of minimal secretion during which hypersensitivity of acinar cells develops. With spontaneous reinnervation, secretion is accentuated by external sympathetic vasomotor adrenergic drive. This shows that submandibular glands can remain viable despite complete separation from their normal nerve supply and are capable of regaining a substantial secretory activity for years.
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- 2008
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23. Pharmacological prevention of radiation-induced dry eye-an experimental study in a rabbit model
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Julia Beutel, Christina Schröder, Thilo Wedel, Hartwig Kosmehl, Katharina von Hof, Gerd Geerling, Samer G. Hakim, Peter Sieg, and Dirk Rades
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medicine.medical_specialty ,Lidocaine ,Radiation-Protective Agents ,Lacrimal gland ,Scintigraphy ,Lacrimal apparatus ,Immunoenzyme Techniques ,Cellular and Molecular Neuroscience ,Amifostine ,Internal medicine ,medicine ,Animals ,Tear secretion ,Radionuclide Imaging ,medicine.diagnostic_test ,business.industry ,X-Rays ,Lacrimal Apparatus ,Pilocarpine ,Tenascin ,Actins ,Sensory Systems ,Up-Regulation ,Radiation Injuries, Experimental ,Ophthalmology ,medicine.anatomical_structure ,Endocrinology ,Tears ,Dry Eye Syndromes ,Female ,Rabbits ,business ,medicine.drug - Abstract
To evaluate the radioprotective effect of lidocaine, amifostine and pilocarpine on lacrimal glands.Twenty-five rabbits were randomized into five groups: the control, irradiated/sham-treated, irradiated/lidocaine-pretreated, irradiated/amifostine-pretreated and irradiated/pilocarpine-pretreated groups. One week before irradiation, 72 h and 1 month afterward, the inferior lacrimal gland was investigated histomorphologically, immunohistochemically [tenascin-C and alpha smooth muscle actin (alpha-SMA)] and functionally using scintigraphy and the Schirmer test.Compared with control animals, the lacrimal ejection fraction (LEF) in the irradiated/sham-treated group was significantly reduced 72 h afterwards. Pilocarpine- as well as amifostine-pretreated animals showed a slightly lower reduction. Lidocaine stabilized the LEF. Immunohistochemically, a significant loss of alpha-SMA and an up-regulation of tenascin-C expression in irradiated/untreated glands were evident. Pretreatment with lidocaine and amifostine-but not with pilocarpine-induced lower up-regulation of TN-C expression 72 h after radiation. One month after irradiation a reduction of the immunhistochemical changes at all was found. Ultrastructural damage was observed in irradiated/non-treated and pilocarpine-pretreated glands, whereas lidocaine and amifostine preserved the ultrastructure.Morphologic and functional findings could prove a prevailing protection profile of amifostine and especially of lidocaine on lacrimal glands. This may provide a prophylactic approach in the radioprotection of the lacrimal glands during radiotherapy of the orbital region.
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- 2007
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24. Differential Gene Expression of the Proto-oncogene VAV3 and the Transcript Variant VAV3.1 in Oral Squamous Cell Carcinoma
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Thomas, Trenkle, Samer G, Hakim, Hans-Christian, Jacobsen, and Peter, Sieg
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Gene Expression Regulation, Neoplastic ,Carcinogenesis ,Cell Movement ,Transforming Growth Factor beta ,Cell Line, Tumor ,Carcinoma, Squamous Cell ,Humans ,Protein Isoforms ,Mouth Neoplasms ,Neoplasm Metastasis ,Proto-Oncogene Proteins c-vav ,Proto-Oncogene Mas ,Signal Transduction - Abstract
The VAV proteins VAV1, VAV2 and VAV3 have been identified as important molecules in tumorigenesis, tumor growth and cell migration. In addition to the full-length isoforms, a much shorter family member, VAV3.1, also known as VAV3 isoform 2, is known to be differentially expressed in a broad variety of tissues. Furthermore, VAV3.1 was shown to be down-regulated in cultured keratinocytes by the growth factors epidermal growth factor (EGF) EGF and transforming growth factor beta (TGFβ) TGFβ which in turn play important roles in the pathogenesis of oral squamous cell carcinoma (OSCC). Herein we showed that VAV3.1 is underexpressed in OSCC tissue samples compared to corresponding normal mucosa. We further demonstrated a trend of distinctive down-regulation of mRNA for VAV3.1 in tissues of locally advanced OSCC that have already metastasized to regional lymph nodes, indicating an increased malignant potential of tumors with low VAV3.1 mRNA expression. Moreover, in other studies a correlation between increased VAV3 expression and cancer progression was shown. In the present study, the analyzed OSCC tissue samples showed no significant change of VAV3 mRNA expression. Taken together, our data support the hypothesis that molecular interactions and signaling cascades of VAV3 can be regulated or directed by the competing molecule VAV3.1. Additionally, discrete and different functions of VAV3.1 in metastasis and tumorigenesis are conceivable.
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- 2015
25. Impact of body mass index, gender, and smoking on thickness of free soft tissue flaps used for orofacial reconstruction
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Peter Sieg, Thomas Trenkle, Henning Wieker, Hans-Christian Jacobsen, and Samer G. Hakim
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Adult ,Male ,medicine.medical_specialty ,Tobacco use ,Free Tissue Flaps ,Transplant Donor Site ,Body Mass Index ,Young Adult ,Sex Factors ,Forearm ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Aged ,Skin ,Ultrasonography ,Fibular flap ,Leg ,Mouth ,business.industry ,Smoking ,Age Factors ,Soft tissue ,Middle Aged ,Plastic Surgery Procedures ,Myocutaneous Flap ,Surgery ,Scapula ,medicine.anatomical_structure ,Otorhinolaryngology ,Transplanted tissue ,Thigh ,Face ,Female ,Oral Surgery ,business ,Nuclear medicine ,Body mass index - Abstract
Donor-site selection may play an important role in the reconstruction of large orofacial defects. The thickness and structure of transplanted tissue has to fit those of the recipient site to achieve a satisfactory outcome. To evaluate the thickness of free flaps that are frequently used for orofacial reconstruction and its association with body mass index (BMI), gender, and smoking, a prospective study was conducted. A total of 122 volunteers were included in the study, and their data regarding BMI, gender, and tobacco use were documented. Ultrasonography was used to evaluate the thickness of the radial and ulnar forearm flaps (RFFF and UFFF, respectively), the scapular and parascapular flaps (SF and PSF, respectively), the anterolateral thigh flap (ALT), and the free fibular flap (FF). Correlation and regression analysis were performed to assess any relationship among parameters and to investigate their effect on flap thickness. The UFFF showed the lowest thickness (0.65 ± 0.16 cm), followed by the RFFF (0.83 ± 0.20 cm). The FF showed a comparable thickness (0.82 ± 0.26 cm), followed by the SF (0.99 ± 0.13 cm) and the PSF (1 ± 0.14 cm). The ALT flap displayed the greatest thickness (1.42 ± 0.42 cm) and correlated especially with BMI and gender, whereas the UFFF was the thinnest with relatively constant values, regardless of potential influential factors.
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- 2015
26. The value of FDG-PET and bone scintigraphy with SPECT in the primary diagnosis and follow-up of patients with chronic osteomyelitis of the mandible
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Isabel Lauer, Samer G. Hakim, Peter Sieg, D. Hermes, C.W.R. Bruecker, H. Ch. Jacobsen, S. Eckerle, and A. Froehlich
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Adult ,Time Factors ,Radiography ,Mandible ,Scintigraphy ,Sensitivity and Specificity ,Fluorodeoxyglucose F18 ,Predictive Value of Tests ,medicine ,Humans ,False Positive Reactions ,Prospective Studies ,Prospective cohort study ,False Negative Reactions ,Aged ,Aged, 80 and over ,Tomography, Emission-Computed, Single-Photon ,medicine.diagnostic_test ,business.industry ,Osteomyelitis ,Middle Aged ,medicine.disease ,Otorhinolaryngology ,Bone scintigraphy ,Positron emission tomography ,Positron-Emission Tomography ,Chronic Disease ,Surgery ,Radiopharmaceuticals ,Oral Surgery ,Osteitis ,business ,Nuclear medicine - Abstract
Objective To appraise the value of FDG-PET and bone scintigraphy using SPECT in the primary diagnosis and follow-up of patients with chronic osteomyelitis of the mandible (COM). Methods In a prospective study the pattern of tracer uptake was investigated using 2 diagnostic methods in 42 patients. Results were compared with histology and radiographs as well as clinical and laboratory parameters. Results The use of FDG-PET in the primary diagnosis of COM resulted in a sensitivity of 64% and a specificity of 77.7%. The sensitivity of SPECT was 84% and the specificity 33.3%. During the follow-up period of these patients the sensitivity of SPECT increased to 93.7%, while the specificity decreased (6.6%). The sensitivity and specificity of FDG-PET for this follow-up group were 62.5 and 80%, respectively. Conclusion Because of its high sensitivity, SPECT is vastly superior to other diagnostic methods in initiating treatment. In the follow-up period it might be replaced by FDG-PET, which reflects the disease course better and indicates the time of clinical remission.
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- 2006
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27. Tape recorded hypnosis in oral and maxillofacial surgery—basics and first clinical experience
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Samer G. Hakim, Peter Sieg, Daniel Truebger, and D. Hermes
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Adult ,Hypnosis ,medicine.medical_specialty ,Hypnosis, Dental ,Adolescent ,Anesthesia, Dental ,Sedation ,Oral Surgical Procedures ,MEDLINE ,Objective data ,Dental Anxiety ,medicine ,Humans ,Patient compliance ,Aged ,Aged, 80 and over ,business.industry ,Middle Aged ,Surgery ,Clinical trial ,Otorhinolaryngology ,Tape Recording ,Oral and maxillofacial surgery ,Oral Surgery ,medicine.symptom ,business ,Anesthesia, Local - Abstract
Summary Background Surgical treatment of diseases of the oral and maxillofacial region under local anaesthesia is quite commonly restricted by limited patient compliance. ‘Medical Hypnosis’ could be an alternative to treatment under pharmacological sedation. With this method, both autosuggestive and other suggestive procedures are used for anxiolysis, relaxation, sedation and analgesia of the patient. The purpose of this paper was to see whether there could be any potential for this treatment when operating on oral and maxillofacial patients. Methods During a 1-year-trial period, 209 operations under combined local anaesthesia/medical hypnosis were carried out on 174 non-preselected patients between the ages of 13 and 87 years. The surgical range covered oral, plastic and reconstructive, oncological, septic and trauma operations. Results Medical hypnosis turned out to be a reliable and standardizable method with high patient compliance. Remarkable improvements in treatment conditions for both patient and surgeons were achieved in 93% of cases. Conclusion Controlled clinical studies are now necessary to obtain objective data on the effectiveness of hypnosis-induced intraoperative effects in oral and maxillofacial surgery.
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- 2005
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28. Early immunohistochemical and functional markers indicating radiation damage of the parotid gland
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Peter Sieg, Samer G. Hakim, D. Hermes, Isabel Lauer, Roger Nadrowitz, H. Ch. Jacobsen, and Hartwig Kosmehl
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Male ,medicine.medical_specialty ,Pathology ,medicine.medical_treatment ,Scintigraphy ,Salivary Glands ,Statistics, Nonparametric ,Radiotherapy, High-Energy ,stomatognathic system ,Salivary Gland Tissue ,Internal medicine ,medicine ,Animals ,Parotid Gland ,Radionuclide Imaging ,Saliva ,General Dentistry ,Sodium Pertechnetate Tc 99m ,Salivary gland ,medicine.diagnostic_test ,biology ,Tenascin C ,Tenascin ,Immunohistochemistry ,Actins ,Parotid gland ,Radiation therapy ,Radiation Injuries, Experimental ,medicine.anatomical_structure ,Endocrinology ,biology.protein ,Female ,Rabbits ,Radiopharmaceuticals ,Antibody - Abstract
In order to evaluate the correlation between functional impairment and changes in the expression pattern of immunohistochemical antibodies in the early phase of radiation-induced dysfunction of salivary glands, eight rabbits were scintigraphically examined prior to and 24 h after irradiation with 15 Gy. The parotid glands were studied using HE-staining, Ki-67, alpha-smooth muscle actin (ASMA) and tenascin-C antibodies at every scintigraphic examination. The results demonstrated a significant alteration in the 99mTc-pertechnetate uptake in all irradiated glands. HE-staining showed no relevant impairment of salivary gland tissue in this early phase. Immunohistochemically, we observed a marked re-distribution of ASMA and tenascin-C as well as a reduction of the proliferating rate of acinar cells. This immunohistochemical change correlated with the functional impairment manifested scintigraphically. This study proves the possibility to assess disorders of salivary gland function with immunohistological antibodies as early as 24 h after irradiation and yields the prerequisites to prove the effects of radioprotective agents on salivary gland tissues.
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- 2004
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29. Mehrjahresverlauf nach Autotransplantation der Unterkieferspeicheldr�se bei vernarbender Keratokonjunktivitis mit absolutem Tr�nenmangel
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G. Geerling, Christina Schröder, Samer G. Hakim, Peter Sieg, and J R O Collin
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Gynecology ,Transplantation ,Ophthalmology ,medicine.medical_specialty ,business.industry ,KERATOCONJUNCTIVITIS SICCA ,Medicine ,Long term results ,business ,medicine.disease ,Ocular surface ,Keratoconjunctivitis - Abstract
Eine Unterkieferspeicheldruse kann durch Transplantation in die Schlafenregion zur Benetzung bei vernarbender Keratokonjunktivitis mit absolutem Tranenmangel genutzt werden. Wir berichten uber unsere Erfahrungen mit diesem Verfahren. In einer prospektiven, kontrollierten, klinischen Kohortenstudie untersuchten wir die Entwicklung von Schirmer-Test, Fluoreszein-Break-up-time, subjektiver Beschwerdesymptomatik, Verwendung von pharmazeutischen Tranenersatzmitteln, Visus, Bengalrosafarbung und Bindehauthyperamie bei 14 Augen mit vitalem Speicheldrusentransplantat und 11 trockenen Augen ohne speichelartige Benetzung bei schwerster vernarbender KCS. Uber 3,3 Jahre postoperativ zeigte sich in der Transplantatgruppe gegenuber praoperativ und gegenuber der Kontrollgruppe eine signifikante Verbesserung des Beschwerdebildes bei gleichzeitig reduzierter Verwendung von Tranenersatzmitteln. Bei extrem trockenem Auge kann die Transplantation einer autologen Unterkieferspeicheldruse die Benetzung und die oft schwersten Beschwerden des Tranenmangels deutlich und langfristig verbessern. Das Verfahren eignet sich zur symptomatischen Therapie bei verzweifelten Fallen des absoluten Tranenmangels.
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- 2003
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30. Subcutaneous fat layer in different donor regions used for harvesting microvascular soft tissue flaps in slender and adipose patients
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Samer G. Hakim, Peter Sieg, S. Bierwolf, and D. Hermes
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business.industry ,Ultrasound ,Soft tissue ,Adipose tissue ,Nutritional status ,Anatomy ,Subcutaneous fat ,medicine.anatomical_structure ,Otorhinolaryngology ,Forearm ,medicine ,Surgery ,Oral Surgery ,business ,Body mass index ,Layer (electronics) - Abstract
The aim of this study is to provide valid data concerning the thickness of the subcutaneous fat layer in seven donor regions which are most commonly used for soft tissue replacement in the head and neck region. Furthermore the study focuses on differences in thickness of this layer depending on the nutritional status and sex. In 100 volunteers the thickness of the subcutaneous fat layer was evaluated using ultrasound in seven potential donor regions: radial and ulnar forearm, lateral upper arm, scapular and parascapular region, abdominal/supra-umbilical region and the lateral calf. Volunteers were divided into 4 groups: male and female, slender (body mass index [BMI] 30). Data obtained was compared and differences were proven to be statistically significant (Student's t-test, P
- Published
- 2003
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31. Regeneration potential of the submandibular gland after transplantation
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Peter Sieg, S.J. Zimmermann, Hartwig Kosmehl, I. Lauer, and Samer G. Hakim
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Pathology ,medicine.medical_specialty ,General Veterinary ,medicine.diagnostic_test ,business.industry ,Regeneration (biology) ,Ischemia ,Warm ischemia ,medicine.disease ,Scintigraphy ,Submandibular gland ,Transplantation ,medicine.anatomical_structure ,stomatognathic system ,medicine ,Tracer uptake ,Animal Science and Zoology ,In patient ,business - Abstract
Summary The aim of this study was to evaluate the regeneration potential of the submandibular gland and the associated morphological and functional impairment after a transient warm ischemia as a result of submandibular gland transfer in humans. 42 rabbits were used for the study. After 1.5 h of transient ischemia, submandibular glands were studied histologically in the following 14 days, one month, two and four months in 32 rabbits. Additionally, the glands were functionally evaluated after one and four months in eleven of these rabbits. Ten rabbits were used to establish the scintigraphic method. In the evaluation of the results unpublished data derived from a previous study by our group has also been considered. The Ki-67 index showed a significant increase of the proliferating rate reaching a peak after 14 days ( p = 0.006) and still evident after four months involving mostly the terminal ductal system. There was only a slight increase in the tracer uptake of ischemic glands after one month and a more pronounced one after four months. It was concluded that initial loss of acinar cells by 1.5 h of ischemia released a regeneration process which stabilised after 14 days but continued throughout the whole time of the study. These results correlate with clinical observation in patients with submandibular gland transfer for the treatment of keratoconjunctivitis sicca and explain the alternating secretory function observed within the four months following surgery. Scintigraphy has been found to play a limited role in the evaluation of the regeneration process.
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- 2002
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32. Defect-related variations in mandibular reconstruction using fibula grafts
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Peter Sieg, S. Bierwolf, J.O Zieron, and S.G Hakim
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Mandible ,Soft tissue ,Anatomy ,Microsurgery ,Ablation ,Surgery ,Plastic surgery ,Otorhinolaryngology ,Bone plate ,Medicine ,Oral Surgery ,Fibula ,business ,Complication - Abstract
Despite the popularity of the donor region 'laterodorsal calf' with the fibula, the flexor muscles and the overlying skin for microsurgical bone and soft tissue transfer some limitations and possible pitfalls have to be considered. We report on 93 patients who had 96 reconstructions, 65 with and 31 without soft tissue transfer in 8 years using microvascular fibular grafts for mandibular replacement and oromandibular reconstruction. Six patients died within 4 weeks and eight flaps were lost. Necrosis of the skin paddle occurred in 7 (11%) of 61 cases with uncomplicated bony healing.
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- 2002
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33. Autotransplantation der Unterkieferspeicheldrüse bei absoluter Keratoconjunktivitis sicca - Einfluss auf die okulare Oberfläche
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Gerd Geerling, Samer G. Hakim, Peter Sieg, Kai Honnicke, Christina Schröder, and Carsten Framme
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medicine.medical_specialty ,genetic structures ,business.industry ,Impression cytology ,Submandibular gland ,eye diseases ,Transplantation ,Ophthalmology ,medicine.anatomical_structure ,stomatognathic system ,Medicine ,sense organs ,business ,Ocular surface - Published
- 2002
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34. Oral rehabilitation with dental implants and quality of life following mandibular reconstruction with free fibular flap
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Falko Wahnschaff, Thomas Trenkle, Peter Sieg, Hans-Christian Jacobsen, and Samer G. Hakim
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Male ,medicine.medical_treatment ,Dentistry ,Free Tissue Flaps ,03 medical and health sciences ,0302 clinical medicine ,stomatognathic system ,Quality of life ,Surveys and Questionnaires ,medicine ,Humans ,Dental Restoration Failure ,Fibula ,Mandibular reconstruction ,Dental implant ,General Dentistry ,Feeding tube ,Orthodontics ,Dental Implants ,Rehabilitation ,business.industry ,030206 dentistry ,Middle Aged ,Masticatory force ,stomatognathic diseases ,Mandibular Neoplasms ,Cross-Sectional Studies ,Treatment Outcome ,030220 oncology & carcinogenesis ,Quality of Life ,Female ,Implant ,Mandibular Reconstruction ,business ,Follow-Up Studies - Abstract
Bony reconstruction of jaw defects using the free fibular flap and dental rehabilitation mostly requires insertion of dental implants within the transferred fibula bone. The aim of this paper was to discuss results of the implant stability with data on the possible benefit for the patient's quality of life after such treatment.For clinical outcome of implants, we evaluated 26 patients with a total number of 94 dental implants after a follow-up period of 12 to 132 months. A group of 38 patients who underwent mandibular reconstruction with free fibular flap could be included in the life-quality study. Evaluation included 23 patients with and 15 patients without implant-borne restoration. The quality of life was assessed using the standard QLQ C-30 questionnaire and the HN35 module of the European Organisation for Research and Treatment of Cancer (EORTC).Of implants, 94.7 % were stable at the time of investigation and could be used for prosthesis. Patients with dental implants reported improvement of life quality along with better scores in most function and symptom scales; however, only values for global health status (QL2), absence of dyspnea (DY) and absence of feeding tube (HNFE) were significantly better than in the control group.Dental implant insertion in fibula grafts along with implant-borne restoration is a proven concept and might lead to improved quality of life following ablative surgery of the jaw. The effect on the quality of life is not as predictable as on the implant stability.Patients with bony defects of the jaw require bony reconstruction. This allows further masticatory rehabilitation using dental implants and might lead to improved quality of life.
- Published
- 2014
35. Single photon emission tomography: Scintigraphy in the assessment of mandibular invasion by head and neck cancer
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Joerg O. Zieron, Stephan Remmert, Peter Sieg, and Isabel Lauer
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Tomography, Emission-Computed, Single-Photon ,medicine.diagnostic_test ,business.industry ,Head and neck cancer ,Head neck ,medicine.disease ,Scintigraphy ,Sensitivity and Specificity ,Imaging, Three-Dimensional ,Otorhinolaryngology ,Epidermoid carcinoma ,Head and Neck Neoplasms ,Pharyngeal cancer ,Carcinoma, Squamous Cell ,medicine ,Single Photon Emission Tomography ,Retrospective analysis ,Humans ,Neoplasm Invasiveness ,business ,Nuclear medicine ,Head and neck ,Retrospective Studies - Abstract
Background This study was performed to determine the effectiveness of single photon emission tomography (SPET) in contributing to the initial staging of patients with cancers of the head and neck because information about osseous infiltration of head and neck cancer is of major importance for staging and planning of treatment. Methods A retrospective analysis of 89 cases with probable tumor infiltration of the mandible by oral/pharyngeal cancer was undertaken by comparing the preoperative SPET as well as CT-scans, if available, with clinical and postoperative histological examinations. Results For SPET examinations, a sensitivity of 95% and a specificity of 48% were calculated. The positive predictive value was 65%, and the negative predictive value was 93%. CT scans showed a sensitivity of 75% and a specificity of 78%. The positive predictive value was 65%, and the negative predictive value was 93%. Conclusions SPET is a powerful method to detect infiltration of carcinomas into the head and neck skeleton. Its sensitivity is high and superior to CT scans, although the specificity is small due to a high number of false positive results. © 2001 John Wiley & Sons, Inc. Head Neck 23: 979–984, 2001.
- Published
- 2001
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36. Ulnar versus radial forearm flap in head and neck reconstruction: An experimental and clinical study
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Peter Sieg and Stephan Bierwolf
- Subjects
Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Surgical Flaps ,Forearm ,medicine.artery ,medicine ,Humans ,Radial artery ,Ulnar artery ,Aged ,Aged, 80 and over ,Wound Healing ,integumentary system ,business.industry ,Middle Aged ,Plastic Surgery Procedures ,Microsurgery ,Surgery ,body regions ,Plastic surgery ,Dissection ,medicine.anatomical_structure ,Otorhinolaryngology ,Head and Neck Neoplasms ,Skin grafting ,Female ,business ,Hair ,Subcutaneous tissue - Abstract
Background To consider the pros and cons of the microvascular ulnar forearm flap compared with its radial counterpart, this study compares the use of these two flaps for head and neck reconstruction. Methods In 75 patients, 51 ulnar and 24 radial forearm flaps were used. Both groups were compared regarding flap dissection, suitability of the flap for the recipient region, complication rate, and secondary morbidity in the donor region. Furthermore, in 40 healthy volunteers, the thickness of the subcutaneous tissue layer was measured by use of ultrasonography. Results Flap survival rate, respectively wound healing, in the recipient region showed no differences. Clinical and experimental results demonstrated a thinner subcutaneous layer in the ulnar aspect of the forearm. Compared with its radial equivalent, closure of the ulnar donor side by skin grafting resulted in a significantly lower complication rate. Conclusions The ulnar forearm flap is favored because of the less hairy skin of the ulnar forearm region, the thinner layer of subcutaneous tissues, and the more conveniently located donor area. The ulnar forearm pedicle is long compared with alternative transplants but shorter than the radial equivalent. © 2001 John Wiley & Sons, Inc. Head Neck 23: 967–971, 2001.
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- 2001
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37. Microvascular Submandibular Gland Transfer for Severe Cases of Keratoconjunctivitis Sicca
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Hartwig Kosmehl, Helmut von Domarus, Kirsten Warnecke, Peter Sieg, Isabel Lauer, and Gerd Geerling
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Male ,Pathology ,medicine.medical_specialty ,Adolescent ,Eye disease ,Submandibular Gland ,Keratoconjunctivitis Sicca ,Transplantation, Autologous ,Surgical methods ,Necrosis ,Animal model ,stomatognathic system ,Ischemia ,Animals ,Humans ,KERATOCONJUNCTIVITIS SICCA ,Medicine ,Salivary gland ,business.industry ,Anastomosis, Surgical ,medicine.disease ,Warm ischemia ,Immunohistochemistry ,Submandibular gland ,stomatognathic diseases ,Treatment Outcome ,medicine.anatomical_structure ,nervous system ,Surgery ,Blood supply ,Rabbits ,Tissue Preservation ,business - Abstract
Free submandibular salivary gland transfer was investigated as a surgical method for the treatment of severe keratoconjunctivitis sicca. In an animal model, we examined the tolerance of warm ischemia of the submandibular gland. After temporary interruption of the blood supply (1 to 6 hours), the morphologic changes in the submandibular gland were analyzed histologically and immunohistochemically in 41 rabbits. From 1.5 hours ischemia onward, an increasing structural damage of the parenchyma with emphasis on the secretory cells was seen. Six hours of ischemia caused total necrosis of the salivary gland. Our clinical experience includes 24 highly selected patients suffering from keratoconjunctivitis sicca, in whom we transferred 31 autologous submandibular glands to the temple for permanent autologous tear substitution within the past 4 years. The glands were implanted into a pocket prepared in the temporalis muscle, and the nourishing vessels were anastomosed to the superficial temporal artery and vein. The submandibular duct was implanted into the upper lateral conjunctival fornix. The transferred glands were left denervated. In addition to the clinical examination, scintigraphy with Tc 99m pertechnetate was used to document the graft's viability after the transfer. Viable incorporation with longstanding secretory function occurred in 26 of the 30 transplanted denervated salivary glands. The resulting lubrication of the treated eyes was irregular for up to 3 months in almost even case. One year after surgery, all patients with a viable transplant developed at least occasional epiphora, which was surgically managed by reducing the size of the graft in 10 patients. No severe side effects were seen in this series. The ophthalmologic evaluation of the method included the assessment of dry eye symptoms and of the volume and quality of ocular lubrication (Schirmer test, fluorescein break-up time), the pathology of the ocular surface (rose bengal staining), and the need for pharmaceutical tear substitutes. One year after surgery, 18 of 27 cases assessed were judged as significantly improved by these tests.
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- 2000
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38. Ulnaris- vs. Radialisunterarmlappen in der Rekonstruktion von Mundhöhle und Gesichtsregion
- Author
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Peter Sieg
- Subjects
Gynecology ,medicine.medical_specialty ,Otorhinolaryngology ,business.industry ,Medicine ,Oral Surgery ,business - Abstract
Der mikrovaskulare Ulnarisunterarmlappen wird als fasziokutanes Transplantat fur die Rekonstruktion von Weichgewebsdefekten der Kopf-Hals-Region im Vergleich mit dem Radialisunterarmlappen vorgestellt. Bei 67 Patienten wurden im Rahmen rekonstruktiver Eingriffe 44 Ulnaris- und 23 Radialislappen verwendet. Beide Transplantatgruppen wurden im Hinblick auf Praparationsaufwand, Eignung der Transplantate, Komplikationsrate und Sekundarmorbiditat der Entnahmeregion verglichen. Den Ulnarislappen favorisieren wir wegen einer geringeren Behaarung der ulnaren Unterarmregion und dem asthetisch gunstiger gelegenen Sekundardefekt, dessen Versorgung mit einer geringen Komplikationsrate bezuglich der Wundheilung behaftet ist. Als Nachteil ist der im Vergleich zu alternativen Transplantaten zwar lange, aber im Vergleich zum Radialislappen kurzere Gefasstiel zu nennen.
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- 2000
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39. Transplantation of the autologous submandibular gland in patients with severe keratoconjunctivitis sicca - 2 years' experience
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Gerd Geerling, Peter Sieg, Carsten H. Meyer, H. Laqua, and Gerd-Otto Bastian
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medicine.medical_specialty ,Pathology ,Conjunctiva ,business.industry ,medicine.medical_treatment ,Eye disease ,Microsurgery ,medicine.disease ,Submandibular gland ,eye diseases ,Autotransplantation ,Surgery ,Transplantation ,Ophthalmology ,Artificial tears ,medicine.anatomical_structure ,medicine ,Temporal fossa ,business - Abstract
Introduction: The conservative treatment of the most severe cases of keratoconjunctivitis sicca (KCS) can be sometimes frustrating. Especially with an underlying autoimmunologic disorder, even the application of artificial tears as often as every 5 min may not prevent further damage to the ocular surface. A microvascular transplantation of the autologous submandibular gland (SG) can be performed by a maxillo-facial surgeon as an alternative approach for those cases. We report 2 years of ophthalmological experience with the results of this procedure. Material and methods: To date 27 operations have been performed in 23 patients. The SG was moved from its natural site into the temporal fossa. The secretory duct was implanted into the conjunctival fornix and the gland's vessels connected to the temporal artery and vein. A complete ophthalmological examination has been performed in 25 eyes of 21 patients up to 1 year and in 11 eyes of 9 patients 2 years after surgery. Results: Three months and 1 year postoperatively 19 of 25, and 2 years postoperatively 8 of 11 transplants remained vital. The baseline secretion increased in patients with a vital transplant from an average of 1.6 ± 1.3 mm before the operation to 16.2 ± 11.3 mm after 3 months and 20.6 ± 10.6 mm after 1 year. Ten of 19 vital grafts were reduced 1 year after transplantation in a minor second procedure to control an increasing epiphora. Subsequently baseline secretion was reduced to 13.6 ± 8.2 mm 2 years after transplantation. Patients with a vital graft reported in 84 % of cases (16 of 19) at 3 months, and 79 % at 1 year (15 of 19) and 2 years (7 of 8), a strong relief of dry eye symptoms. In 58 % (3 months), 79 % (1 year) and 63 % (2 years) of the eyes with a vital transplant all artificial tear substitution could be stopped. Break-up time increased significantly, resulting in reduced bengal rose staining. Conclusion: The transfer of the autologous SG into the temporal fossa can be used to provide patients with very severe KCS with a continuous, endogenous source of ocular lubrication. Despite surgical denervation the graft maintains a sufficient baseline secretion over a period of years. Subjective symptoms and the application of pharmaceutical lubricating substances are reduced to a large extent. If epiphora occurs, it can be controlled by surgically reducing the transplant. The influence of SG saliva on the ocular surface is the object of ongoing studies.
- Published
- 1998
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40. Transplantation of the autologous submandibular gland for most severe cases of keratoconjunctivitis sicca
- Author
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Gerd Geerling, Horst Laqua, Peter Sieg, and Gerd-Otto Bastian
- Subjects
medicine.medical_specialty ,Conjunctiva ,Eye disease ,medicine.medical_treatment ,Submandibular Gland ,Keratoconjunctivitis Sicca ,Anastomosis ,Scintigraphy ,Transplantation, Autologous ,medicine ,Humans ,Radionuclide Imaging ,Sodium Pertechnetate Tc 99m ,medicine.diagnostic_test ,business.industry ,Graft Survival ,medicine.disease ,Submandibular gland ,eye diseases ,Surgery ,Transplantation ,Ophthalmology ,Artificial tears ,medicine.anatomical_structure ,Tears ,Amylases ,Immunoglobulin A, Secretory ,Temporal fossa ,business - Abstract
Objective: This study aimed to examine the long-term qualitative and quantitative function of the secretion of transplanted autologous submandibular glands in patients with most severe keratoconjunctivitis sicca. Design: The study design was clinical. Participants: The authors performed 26 operations in 22 patients. A complete ophthalmologic examination was performed in 16 eyes of 13 patients 1 week and 3 months and in 8 eyes of 8 patients 1 year after surgery. Intervention: The submandibular gland was moved from its natural site into the temporal fossa. The glands supplying vessels were connected to the temporal artery and vein, and its secretory duct was implanted into the conjunctival fornix. Main Outcome Measures: Scintigraphy with Tc 99m Pertechnetate was used to document the graft vitality. Subjective symptoms and application frequency of artificial tears were recorded. Baseline as well as stimulated secretion and breakup time were measured and rose bengal staining and ocular ferning test were performed. In selected cases, the secretory product could be sampled for the detection of electrolytes, amylase, and secretory immunoglobulin A (SIgA). Results: Scintigraphy showed vital gland tissue in 14 of 16 grafts at 3 months and 6 of 8 grafts at 1 year after surgery. Two of the 16 transplants were lost completely during the first 3 postoperative months, 1 because of an underlying autoimmunopolyendokrinopathy and the other because of an insufficient vascular anastomoses. In eyes with a vital transplant, baseline secretion and breakup time were increased significantly at 3 months and 1 year after surgery. Patients with a vital transplant reported a strong relief of symptoms and were able to stop taking artificial tear substitution at 1 year. Electrolytes showed a fluctuating concentration. A year after transplantation, the SIgA and amylase concentrations were more than ten times increased compared to normal tear values. Conclusion: Microvascular transferral of an autologous, paralytic submandibular gland results in a significant relief of subjective symptoms, a reduction of artificial tear applications, and an increase of baseline secretion over the first postoperative year. The composition and volume of the secretory product fluctuate, but high values of SIgA and amylase show an actively secreting graft. Although the authors' long-term experience still is limited, they believe that the procedure is a promising alternative approach for desperate dry eye conditions.
- Published
- 1998
- Full Text
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41. A new non-endoscopic intraoral approach for open reduction and internal fixation of subcondylar fractures of the mandible
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Thomas Trankle, Harald Kimmerle, Hans-Christian Jacobsen, Samer G. Hakim, and Peter Sieg
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medicine.medical_treatment ,Operative Time ,Joint Dislocations ,Fracture site ,Dentistry ,Fracture Fixation, Internal ,Mandibular Fractures ,Occlusion ,Bone plate ,medicine ,Internal fixation ,Humans ,Joint dislocation ,Reduction (orthopedic surgery) ,Miniaturization ,business.industry ,Intraoral approach ,Mandible ,Mandibular Condyle ,Equipment Design ,medicine.disease ,Otorhinolaryngology ,Manipulation, Orthopedic ,Surgery ,Oral Surgery ,business ,Bone Plates ,Follow-Up Studies - Abstract
Open reduction and internal fixation (ORIF) of subcondylar fractures of the mandible is a widely accepted treatment concept aimed at reconstruction of the vertical height of the mandibular ramus and restoration of occlusion. Here, we describe new instruments designed for ORIF via an intraoral approach using a single inverted y-miniplate. The special design allows sufficient visualisation of the fracture site and enables the establishment of a standardised procedure for the treatment of both dislocated and non-dislocated fractures. Several manoeuvres are described and some clinical cases are presented. Challenges frequently met during ORIF of subcondylar fractures via the intraoral approach such as limited exposure and visual control of fracture site can be overcome using the instruments-kit presented, which help to optimise this treatment.
- Published
- 2013
42. Comparative biomechanical study on three miniplates osteosynthesis systems for stabilisation of low condylar fractures of the mandible
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Robert Wendlandt, Hans-Christian Jacobsen, Samer G. Hakim, Peter Sieg, Melanie Wolf, and Harald Kimmerle
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Dental Stress Analysis ,Models, Anatomic ,Surface Properties ,Bone Screws ,Torsion, Mechanical ,Dentistry ,Condyle ,Bite Force ,Fixation (surgical) ,Fracture Fixation, Internal ,Mandibular Fractures ,Materials Testing ,Medicine ,Humans ,Fracture Healing ,Osteosynthesis ,Surgical approach ,Miniaturization ,Miniplate osteosynthesis ,business.industry ,Significant difference ,Mandibular Condyle ,Equipment Design ,Elasticity ,Biomechanical Phenomena ,Otorhinolaryngology ,Surgery ,Equipment Failure ,Stress, Mechanical ,Oral Surgery ,business ,Bone Plates ,Muscle Contraction - Abstract
Open reduction and fixation of low condylar fractures of the mandible can be achieved by many osteosynthesis systems that differ in size, shape, and site of placement according to the surgical approach. We investigated the maximum load and rigidity of 4 osteosynthesis systems: the standard double 4-hole straight miniplates, the inverted y-miniplate (with and without self-drilling screws), and the TriLock Delta condyle trauma plate. The standard double 4-hole straight miniplate osteosynthesis achieved the best fixation and resistance in view of a mean (SD) maximum load of 539.8 (100.2)N, followed by the inverted y-miniplate with the self-drilling screws (246.5 (23.8)N), the inverted y-miniplate with standard screws (242.4 (27.2)N), and finally the TriLock Delta plate (167.4 (39.2)N). Analysis of the slope of the force-displacement diagram from 80N to 100N in each group showed that the TriLock Delta miniplate had the highest values for rigidity (17.3 (5.1)N/μm), followed by the inverted y-miniplate groups with self-drilling screws (14.1 (6.4)N/μm), and with standard screws (12.6 (2.5)N/μm). The double 4-hole straight miniplate osteosynthesis had the lowest rigidity (8.7 1.4)N/μm). Despite the significant difference in the maximum load between the double 4-hole miniplates and other investigated osteosynthesis patterns, all groups had sufficient load for the fixation of low condylar fractures of the mandible when postoperative bite forces and the slowly increasing voluntary clenching during healing were considered.
- Published
- 2013
43. Imaging of mandible invasion by oral squamous cell carcinoma using computed tomography, cone-beam computed tomography and bone scintigraphy with SPECT
- Author
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Samer G. Hakim, Jens Konitzer, Konstanze Holl-Ulrich, Henning Wieker, Thomas Trenkle, Peter Sieg, and Hans-Christian Jacobsen
- Subjects
Tomography, Emission-Computed, Single-Photon ,medicine.medical_specialty ,Cone beam computed tomography ,Receiver operating characteristic ,medicine.diagnostic_test ,business.industry ,Mandible ,Gold standard (test) ,Cone-Beam Computed Tomography ,medicine.disease ,medicine.anatomical_structure ,Bone scintigraphy ,medicine ,Carcinoma ,Carcinoma, Squamous Cell ,Humans ,Cortical bone ,Mouth Neoplasms ,Neoplasm Invasiveness ,Radiology ,Tomography ,Nuclear medicine ,business ,General Dentistry - Abstract
The objective of this paper is to evaluate the predictability of preoperative tumour bone invasion of the mandible by squamous cell carcinoma of the oral cavity using CT, cone-beam CT and bone scintigraphy with SPECT. Eighty-four patients who had received CT, SPECT or cone-beam computed tomography (CBCT), as well as a further 48 patients who undergone all these investigations for preoperative evaluation of bone invasion were included in the study. A case–control analysis and the receiver operating characteristics were performed. Histological results of bone specimens served as the gold standard for assessment of bone invasion. CBCT and SPECT showed a comparable sensitivity for bone invasion (93 % [CI 0.816–0.972] and 96 % [CI 0.867–0.990], respectively) which was significantly higher than that of CT (63 % [CI 0.488–0.752]). Further, CBCT obtained higher specificity than SPECT (62 % [CI 0.478–0.743] and 48 % [CI 0.342–0.614], respectively), whereas CT showed the best specificity among the investigation methods (81 % [CI 0.677–0.896]). CT scan provides by its high specificity and positive predictive value a precise imaging technique for clinical routine. However, CBCT shows a much higher sensitivity for cortical bone invasion and a better negative predictive value. With a significantly lower exposure dose it can rule out this invasion effectively and prevent overtreatment. Considering the high-resolution images delivered by CBCT along with minimized artefacts in the mandible it provides an alternative imaging technique, which could be combined and accomplished with another soft-tissue imaging modality like MRI to obtain optimal hard and soft-tissue visualisation in patients with squamous cell carcinoma of the oral cavity.
- Published
- 2013
44. Ulnar artery-based free forearm flap: review of specific anatomic features in 322 cases and related literature
- Author
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Samer G, Hakim, Thomas, Trenkle, Peter, Sieg, and Hans-Christian, Jacobsen
- Subjects
Adult ,Male ,Forearm ,Ulnar Artery ,Head and Neck Neoplasms ,Humans ,Female ,Skin Transplantation ,Plastic Surgery Procedures ,Surgical Flaps ,Aged - Abstract
The ulnar free forearm flap (UFFF) represents a variant of soft tissue transplants for orofacial reconstruction with specific topographic anatomy of the donor-site, which has to be considered during flap raising.Analysis of intraoperative findings during harvest of 322 UFFFs for head and neck reconstruction was performed. Harvest technique in view of variations of skin flap, vascular, and neuronal anatomy is described herein and related literature is reviewed.Aberrant superficial ulnar artery was observed in 1.5% of cases. The Martin-Gruber anastomosis was seen in 11.5%. The dorsal branch of the ulnar nerve was always visible and had to be dissected and separated under the flexor carpi ulnaris muscle and donor-site morbidity was low.Considering local anatomic features and variations, the harvest of the UFFF is safe and survival rates are comparable with those of the radial forearm flap.
- Published
- 2013
45. Radioprotective effect of lidocaine on neurotransmitter agonist-induced secretion in irradiated salivary glands
- Author
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Samer G. Hakim, Gui-qing Liao, Dirk Rades, Andreas Dendorfer, Peter Sieg, Birgit Meller, Matthias Klinger, Yu-xiong Su, and Geza Attila Benedek
- Subjects
medicine.medical_specialty ,Saliva ,Carbachol ,Lidocaine ,Oral Medicine ,Cancer Treatment ,Radiation Therapy ,lcsh:Medicine ,Stimulation ,Radiation-Protective Agents ,Muscarinic Agonists ,Salivary Glands ,Oral Diseases ,stomatognathic system ,Internal medicine ,Muscarinic acetylcholine receptor ,medicine ,Animals ,Parotid Gland ,lcsh:Science ,Multidisciplinary ,Salivary gland ,Radiotherapy ,Chemistry ,lcsh:R ,Cancers and Neoplasms ,Neurotransmitter agonist ,Head and Neck Tumors ,Parotid gland ,medicine.anatomical_structure ,Endocrinology ,Oncology ,Otorhinolaryngology ,Head and Neck Cancers ,Head and Neck Surgery ,Gamma Rays ,Medicine ,Surgery ,lcsh:Q ,Rabbits ,medicine.drug ,Research Article - Abstract
BACKGROUND: Previously we verified the radioprotective effect of lidocaine on the function and ultrastructure of salivary glands in rabbits. However, the underlying mechanism of lidocaine's radioprotective effect is unknown. We hypothesized that lidocaine, as a membrane stabilization agent, has a protective effect on intracellular neuroreceptor-mediated signaling and hence can help preserve the secretory function of salivary glands during radiotherapy. METHODS AND MATERIALS: Rabbits were irradiated with or without pretreatment with lidocaine before receiving fractionated radiation to a total dose of 35 Gy. Sialoscintigraphy and saliva total protein assay were performed before radiation and 1 week after the last radiation fraction. Isolated salivary gland acini were stimulated with either carbachol or adrenaline. Ca(2+) influx in response to the stimulation with these agonists was measured using laser scanning confocal microscopy. RESULTS: The uptake of activity and the excretion fraction of the parotid glands were significantly reduced after radiation, but lidocaine had a protective effect. Saliva total protein concentration was not altered after radiation. For isolated acini, Ca(2+) influx in response to stimulation with carbachol, but not adrenaline, was impaired after irradiation; lidocaine pretreatment attenuated this effect. CONCLUSIONS: Lidocaine has a radioprotective effect on the capacity of muscarinic agonist-induced water secretion in irradiated salivary glands.
- Published
- 2013
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46. Allogenic submandibular gland transplantation following hematopoietic stem cell transplantation
- Author
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Peter Sieg, Thomas Trenkle, Martin Nitschke, Philipp Steven, Hans-Christian Jacobsen, and Samer G. Hakim
- Subjects
Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Submandibular Gland ,Visual Acuity ,Graft vs Host Disease ,Hematopoietic stem cell transplantation ,Chimerism ,stomatognathic system ,HLA Antigens ,Xerophthalmia ,medicine ,Humans ,Transplantation, Homologous ,Secretion ,Longitudinal Studies ,Lacrimal Apparatus Diseases ,business.industry ,Hematopoietic Stem Cell Transplantation ,Allogenic transplantation ,medicine.disease ,Allografts ,Submandibular gland ,Tissue Donors ,Surgery ,Transplantation ,medicine.anatomical_structure ,Graft-versus-host disease ,Treatment Outcome ,Otorhinolaryngology ,Oral Surgery ,Stem cell ,Temporal fossa ,business ,Follow-Up Studies - Abstract
Background Autologous submandibular gland transfer for treatment of progressive dry eye symptoms requires a functionally intact submandibular gland. In cases of total function loss of both lacrimal and submandibular glands this procedure has to be modified. Here we report on the first two cases of the allogenic transplantation of a submandibular gland to treat patients suffering from complete functional loss of both glands due to graft-versus-host disease (GvHD) following stem cell transplantation. Methods We carried out allogenic transplantation of the submandibular gland of the matched former stem cell donor to the temporal fossa of the stem cell recipient suffering from GvHD-induced dry eye. The treatment was carried out in two male patients who showed complete donor chimerism to the stem cell donors, so that no immunosuppressive therapy was applied. Results Postoperative clinical assessment of the patients revealed primary success of the procedure. The ocular surface showed improvement of lubrication and reduction of inflammatory signs. In the long-term follow-up sialoscintigraphy revealed lower tracer activity than expected and secretion of saliva-tears decreased. Conclusion Even though the so-called total donor chimerism was assessed allogenic transplantation of the submandibular gland following GvHD-induced dry eye showed signs of organ rejection and therefore initial immunosuppressive therapy after allogenic transplantation has to be considered.
- Published
- 2012
47. Drug mixture which improves survival of ischemic rabbit epigastric skin flaps
- Author
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Surajit Bhattacharya, Bernard McC. O'Brien, Kenneth R. Knight, Peter Sieg, Wayne A. Morrison, Sonia P. Robbins, Morris Ritz, and Diana A. Lepore
- Subjects
Thromboxane ,Vasodilator Agents ,Streptokinase ,Ischemia ,Prostacyclin ,Deferoxamine ,Surgical Flaps ,Adenosine Triphosphate ,medicine ,Animals ,Infusions, Intra-Arterial ,Survival rate ,Urokinase ,Heparin ,business.industry ,Nitrendipine ,Dextrans ,medicine.disease ,Free radical scavenger ,Epoprostenol ,Urokinase-Type Plasminogen Activator ,Drug Combinations ,Reperfusion Injury ,Anesthesia ,Surgery ,Rabbits ,business ,medicine.drug - Abstract
The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl2 (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc.
- Published
- 1994
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48. Radioprotective effect of lidocaine on function and ultrastructure of salivary glands receiving fractionated radiation
- Author
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Andreas Dendorfer, Roger Nadrowitz, Peter Sieg, Samer G. Hakim, Dirk Rades, Hans Christian Jacobsen, Matthias Klinger, Claudia Hemmelmann, Yu-xiong Su, Geza Attila Benedek, and Birgit Meller
- Subjects
Cancer Research ,Side effect ,Lidocaine ,Radioprotective Agent ,medicine.medical_treatment ,Submandibular Gland ,Radiation-Protective Agents ,Lidocaine Hydrochloride ,Pharmacology ,Radiation Tolerance ,Xerostomia ,Salivary Glands ,Microscopy, Electron, Transmission ,medicine ,Animals ,Parotid Gland ,Radiology, Nuclear Medicine and imaging ,Radionuclide Imaging ,Ultrasonography ,Radiation ,business.industry ,Dose-Response Relationship, Radiation ,Submandibular gland ,Parotid gland ,Radiation therapy ,Dose–response relationship ,medicine.anatomical_structure ,Oncology ,Anesthesia ,Female ,Rabbits ,business ,Salivation ,medicine.drug - Abstract
Purpose Radiation-induced xerostomia still represents a common side effect after radiotherapy for head-and-neck malignancies. The aim of the present study was to examine the radioprotective effect of lidocaine hydrochloride during fractionated radiation in an experimental animal model. Methods and Materials To evaluate the influence of different radiation doses on salivary gland function and the radioprotective effect of lidocaine, rabbits were irradiated with 15, 25, 30, and 35 Gy (equivalent doses in 2-Gy fractions equivalent to 24, 40, 48, and 56 Gy, respectively). Lidocaine hydrochloride (10 and 12 mg/kg) was administered before every radiation fraction in the treatment groups. Salivary gland function was assessed by flow sialometry and sialoscintigraphy, and the morphologic changes were evaluated using transmission electron microscopy. Results Functional impairment was first observed after 35 Gy and pretreatment with lidocaine improved radiation tolerance of both parotid and submandibular glands. The use of 12 mg/kg lidocaine was superior and displayed significant radioprotection with regard to flow sialometry and sialoscintigraphy. The ultrastructure was largely preserved after pretreatment with both lidocaine doses. Conclusions Lidocaine represents an effective radioprotective agent and a promising approach for clinical application to avoid radiation-induced functional impairment of salivary glands.
- Published
- 2011
49. Fibula raspatory: a new tool for harvesting microvascular fibular transplants
- Author
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Samer G. Hakim, Peter Sieg, and Hans-Christian Jacobsen
- Subjects
medicine.medical_specialty ,Bone Transplantation ,business.industry ,Plastic Surgery Procedures ,Surgical Instruments ,Surgery ,Otorhinolaryngology ,Bone transplantation ,Fibula ,Tissue and Organ Harvesting ,Medicine ,Humans ,Oral Surgery ,business - Abstract
hoice for the treatment of defects in mandibular continuty. To achieve the desired reconstructive outcome, we use sseous, osteocutaneous, and osteomyocutaneous grafts. The ncouraging clinical and aesthetic outcome of this complex rocedure has been reported previously for both donor and ecipient sites.1–3 Although the procedure is already routine, no specific nstruments have been developed for harvesting this type f flap. Here we describe a new instrument that we have esigned for harvesting fibular transplants, which is manuactured by Medicon, Tuttlingen, Germany (Fig. 1). Though any surgeons may consider this new tool unnecessary, we hink that it facilitates the harvesting procedure.
- Published
- 2010
50. Long-term follow-up after submandibular gland transplantation in severe dry eyes secondary to cicatrizing conjunctivitis
- Author
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John K G Dart, Jaap A. Van Best, Maria Borrelli, Nick Hyde, M Matheson, Gerd Geerling, Ian A. Cree, Gordon Proctor, John Richard O. Collin, John M. Tiffany, Christina Schröder, and Peter Sieg
- Subjects
Adult ,Male ,medicine.medical_specialty ,genetic structures ,Erythema ,Adolescent ,Eye disease ,medicine.medical_treatment ,Submandibular Gland ,Visual Acuity ,Parotid duct ,Transplantation, Autologous ,Cicatrix ,Young Adult ,Postoperative Complications ,stomatognathic system ,medicine ,Humans ,Surface Tension ,Prospective Studies ,Aged ,Aged, 80 and over ,Salivary gland ,business.industry ,Viscosity ,Graft Survival ,Mucins ,Middle Aged ,medicine.disease ,Conjunctivitis ,Submandibular gland ,eye diseases ,Autotransplantation ,Surgery ,Transplantation ,stomatognathic diseases ,Ophthalmology ,medicine.anatomical_structure ,Tears ,Dry Eye Syndromes ,Female ,sense organs ,medicine.symptom ,business ,Follow-Up Studies - Abstract
Purpose To evaluate the long-term results of autologous submandibular gland transplantation in eyes with cicatrizing conjunctivitis and to determine biomechanical and biochemical features of the resulting salivary tear film. Design Prospective, observational case series. Methods Fifteen eyes with cicatrizing conjunctivitis with a viable autologous submandibular gland transplantation were compared with 10 eyes with cicatrizing conjunctivitis and a failed submandibular gland transplantation or no submandibular gland transplantation. Best-corrected visual acuity, frequency of tear substitute instillation, severity of dry eye discomfort, lid margin erythema, conjunctival hyperemia, corneal epithelial edema, tear film break-up time, Schirmer test results, and corneal fluorescein and conjunctival Rose Bengal staining were evaluated. In a subgroup central corneal thickness and sensitivity, corneal epithelial barrier function, conjunctival and lid margin flora, and conjunctival impression cytologic analysis results were evaluated. In 3 patients, preoperative and postoperative tear samples were analyzed for viscosity, surface tension, and presence of mucins. Results Submandibular gland autotransplantation resulted in long-term improvement of subjective, objective, and some ocular surface parameters. Salivary mucins were detectable in salivary tears after submandibular gland transplantation. The viscosity of salivary tears was more similar to normal saliva and the surface tension was intermediate between the 2 original secretions. Conclusions Submandibular gland autotransplantation provides long-term relief from pain and reduces the need for frequent installation of lubricants.
- Published
- 2010
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