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Calcium (Ca) additions during secondary steelmaking are a well-adopted practice to transform solid oxide non-metallic inclusions (NMIs) into globular-shaped liquid oxides. The claimed hypothesis that liquid NMIs reduce SEN clogging has been proven in the past by researchers. However, the exact quantity of Ca needed to transform the physical state of NMIs during steelmaking remains uncertain. Operators in the steel plant use a consistent quantity of Ca additions for specific steel grades, but this approach does not account for the varying physical states and evolving dynamics of NMIs characteristics in each 'heat'. To overcome this, a study was conducted to explore the impact of varying Ca additions on the transformation and behavior of NMIs in low-alloyed Ca-treated steel grades. The aim was to establish a more reliable and responsive approach to Ca treatment, potentially leading to more effective control in preventing submerged entry nozzle (SEN) clogging. The proposed methodology involved online monitoring of NMIs state coupled with controlled variations in Ca addition, deviating from fixed quantity, to observe its effects on NMIs state transformations. Through careful analysis of collected data and the implementation of a data-driven optimizer, this study reports the practical implications of using optimal amounts of Ca during secondary steelmaking. The resulting change due to dynamic calcium silicide (CaSi)-cored wire additions and their impact on SEN clogging were evaluated. The findings reveal the significant role of optimal CaSi wire additions, leading to improved steel castability and a notable 30 pct reduction in SEN clogging tendencies. The results obtained after the implementation of the data-driven optimizer 'ClogCalc' have significant implications for steel manufacturers, offering new insights into enhancing Ca treatment efficiency. [ABSTRACT FROM AUTHOR]

A decision support system was developed using supervised machine learning (ML) approach for optimization of calcium (Ca) additions by continuously monitoring the physical state of non-metallic inclusions (NMIs) inside low-alloyed liquid steels. In this work, two instances were considered to design the base algorithm for the proposed supervisory system: (1) Clogging of submerged entry nozzle (SEN) during continuous casting of steels due to accumulation of solid oxide non-metallic inclusions (NMIs) and (2) Ca treatment during secondary steelmaking for modification of oxide NMIs from solid to liquid state to avoid SEN clogging. At first, experimental investigations were carried out on liquid steel samples from three low-alloyed Ca-treated steel grades from the same steel family to evaluate the characteristics of solid oxide NMIs that cause SEN clogging. In the next step, data-driven models were developed using an in-house ML algorithm trained primarily with process data for calculating the value of the newly proposed dummy parameter 'Clog.' These models, after testing, were architected to develop a supervisory system based on experimental investigations and data-driven models. The objective of this proposed supervisory system was to predict the optimum quantity of Ca needed for successful modification of NMIs from solid to liquid state to avoid SEN clogging based on the forecasted 'Clog' value. Finally, industrial data from ~ 3000 heats were tested to verify the results obtained from the developed supervisory system. The results confirmed that this novel supervisory system could predict the optimum class of Ca for all studied steel grades with 95 to 98 pct accuracy. The integration of this online supervisory system in steel production is expected to minimize operators' corrective actions in achieving realistic control of Ca additions. [ABSTRACT FROM AUTHOR]

Here, we used experiments and Monte Carlo simulations (MC) to identify appropriate poly (ethylene) glycol (PEG) polymer molecular weight (Mw) as the coating agent for iron oxide nanoparticles (IONPs) resulting in individual particles in water. IONPs coated with PEG Mw's ranging from 1500 to 6000 Da showed highly stable dispersions for more than a year. Transmission electron microscopy (TEM) results of the dispersions revealed that particles coated with lower PEG Mw were aggregated, which shifted to individual form with increasing PEG Mw used for coating. We find that this transformation is due to increased PEG layer shell thickness (from 1.47 to 6.46 nm) with increasing PEG Mw (from 1500 to 6000 Da), which imparted sufficient repulsive steric forces to overcome the attractive van der Waals and magnetic forces. To predict appropriate PEG Mw resulting individual IONPs in water, the number density distribution of different PEG Mw coated particles was determined using MC simulation which employs interparticle potentials between the interacting particles as a function of their interparticle distance. The predictions gave very good agreement with our's and others' experimental data. Thus, the study helps to identify a suitable polymer Mw as a coating agent, resulting in individual nanoparticle dispersion. [ABSTRACT FROM AUTHOR]

Congenital heart diseases are most common anomalies associated with tracheoesophageal fistula (TEF) and oesophageal atresia (EA). The physiology and anatomy of heart disease is major determinant factor influencing outcome in patients with TEF/EA. We present a successfully treated case of complex congenital heart anomaly of interrupted aortic arch (IAA) with aortopulmonary window (APW) with TEF/EA. [ABSTRACT FROM AUTHOR]

AlSiMgMn alloy was made by the sand casting under vacuum (SCUV) process at an absolute pressure of 53 mbar and compared its microstructure and mechanical properties with the open sand-casting process. The properties of AlSiMgMn alloy are influenced by the shape and size of the distributed eutectic silicon particle and the iron intermetallic formed during the solidification. The detailed microstructure and mechanical properties of AlSiMgMn alloy made by open sand casting and SCUV were investigated as a function of Fe, Mn, and Mg content. The result shows that the SCUV process developed a Si-granular eutectic structure in sand-cast AlSiMgMn alloy that improves the tensile properties by evenly distributing stress around the hard particles. The α-Al15Si2(FeMn)3 (α-Fe) intermetallic was formed Chinese-script morphology in AlSiMgMn alloy made by open sand casting and SCUV process. β-Fe2SiAl12 (β-Fe) was formed a needle-like structure in open sand casting. Whereas SCUV, β-Fe was seen plate-like structure surrounded by α-Al. This geometrical transformation of β-Fe from the needle-like structure to the plate structure eliminates stress raisers and improves the mechanical properties, especially ultimate tensile strength and elongation by 8.88 and 23.37%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Chirurgie (2731-6971) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Groin hernia repair is performed increasingly more often as an outpatient procedure across the world. However, the rates are extremely different and vary between below 10% and above 90%. The outpatient procedure appears to negatively impact the proportion of laparo-endoscopic repairs. To date, only very few studies have compared inpatient vs outpatient groin hernia repair. Methods: All outpatient and inpatient primary elective unilateral groin hernia repairs performed between 2010 and 2019 were identified in the Herniamed Registry and their treatment and outcomes compared. Results: The 737 participating hospitals/surgeons performed a total of 342,072 primary elective unilateral groin hernia repairs from 2010 to 2019. The proportion of outpatient repairs was 20.2% in 2013 and 14.3% in 2019. Whereas the proportion of laparo-endoscopic repairs among the inpatient cases was 71.9% in 2019, the last year for which data are available, it was only 34.3%.for outpatient repairs. In outpatient groin hernia repairs, the rates of patients aged ≥ 60 years, with ASA score III and IV and risk factors were highly significantly lower. Given this rigorous patient selection for outpatient groin hernia repair, a more favorable perioperative outcome was achieved. At 1-year follow-up there were no significant differences in the pain and recurrence rates. Conclusion: With an appropriate patient selection, outpatient primary elective unilateral groin hernia repair can be performed with acceptable risks and good outcomes. Since to date no studies have compared inpatient vs outpatient groin hernia repair, the impact of a higher rate of outpatient groin hernia repair cannot currently be evaluated. [ABSTRACT FROM AUTHOR]

Introduction: Using registry analyses, a large number of influencing factors on the perioperative outcome of groin hernia repair has been identified. The interactions between several influencing factors and differences in the influencing value have to date been inadequately investigated. Methods: This retrospective analysis of prospectively collected data from the Herniamed Registry included all fully documented cases with minimum age of 16 years and groin hernia repair. Patients were assigned to the risk groups unilateral, bilateral, recurrent and emergency groin hernia repair. Multivariable analysis was performed to investigate the influence of confirmatory defined patient- and procedure-related characteristics on the outcome parameters intraoperative, postoperative general and postoperative surgical complications, complication-related reoperation and total perioperative complications. Results: A highly significantly unfavorable association with the total perioperative complication rate was identified for emergency groin hernia repair, scrotal hernia, anticoagulant medication and coagulopathy. A significantly unfavorable relation with the total perioperative complication rate was found for recurrence procedure, bilateral repair, high age, ASA score III/IV, femoral hernia, antithrombotic medication, smoking, COPD and corticosteroid medication. A significantly favorable correlation with the total perioperative complication rate was observed for the laparo-endoscopic techniques, smaller defects, female gender, normal weight and medial hernia. Conclusion: Both the number of potential influencing factors and their influencing value on the perioperative outcome should be considered when estimating the individual risk of a patient with groin hernia repair. [ABSTRACT FROM AUTHOR]

The application of vacuum in casting technology is very limited. In the present scenario, the vacuum is mainly used in die casting or investment casting, but the application of vacuum in sand casting is not known yet. In the present investigation, the author did a sand casting process under a vacuum, where the melting and pouring of metals were carried out in a vacuum atmosphere. AA6061 castings were made by sand casting under vacuum (SCUV) process in two different absolute pressure of 110 mbar and 56 mbar, and conventional sand casting process at atmospheric pressure. The effect of vacuum on the porosity and mechanical properties of the castings were investigated and compared with the conventional sand casting process. The results revealed that SCUV process reduces the porosity and improves the mechanical properties of sand cast AA6061 alloy. The pore size and the amount of porosity were significantly reduced from 1.548% at atmospheric pressure to 0.302% at 56 mbar of absolute pressure, i.e., 80.49% of reduction. The result also revealed that the mechanical properties of sand casting under vacuum were significantly improved, especially with the ultimate tensile strength from 276.2 to 309.8 MPa, i.e., 12.17% improvement, and elongation increased from 9.8 to 13.15%, i.e., 34.18% improvement. The gases present inside the mold cavity become the final gas porosity in SCUV. In addition, scanning electron microscopy analysis shows solidification shrinkages present in sand cast. SCUV reduces the size of porosity defect that can improve the stress distribution and slow down the crack propagation in sand castings. Therefore, the SCUV enhanced the ultimate tensile strength and elongation of sand casting. [ABSTRACT FROM AUTHOR]

Introduction: There are hardly any studies on the outcome of scrotal compared with medial and lateral inguinal hernias. Therefore, this present multivariable analysis of data from the Herniamed Registry compared the outcome of scrotal vs. lateral vs. medial inguinal hernias and explored the relationship between hernia localization and outcomes. Methods: Included in the analysis were all primary elective unilateral inguinal hernias in men with scrotal, lateral or medial defect localization whose details had been entered into the Herniamed Registry by 712 participating institutions (status February 1, 2019). The relation of the hernia localization with the outcome parameters adjusted for pre-defined confounding patient- and procedure-related variables was analyzed via multivariable binary logistic models. Results: Details of 98,321 patients were thus available for multivariable analysis. These related to 65,932 (67.1%) lateral, 29,697 (30.2%) medial and 2,710 (2.7%) scrotal inguinal hernias. Scrotal hernias were associated with higher patient age, higher BMI, higher ASA score, larger defect, more risk factors and more frequent use of Lichtenstein repair. On the other hand, scrotal hernias were associated less commonly with preoperative pain. Multivariable analysis revealed that scrotal hernias had a highly significantly unfavorable association with postoperative complications, complication-related reoperations and general complications. But scrotal hernias had a highly significantly favorable relation with the pain rates at 1-year follow-up. Medial hernias were the hernia type most often related with recurrence and also had an unfavorable association with the pain rates at 1-year follow-up. Conclusion: Scrotal inguinal hernias demonstrated a very unfavorable relation with the postoperative complication rate, the rate of complication-related reoperations and the rate of general complications. But a very favorable association with chronic pain rates was identified at 1-year follow-up. Medial inguinal hernia had an unfavorable relation with the recurrence and pain rates. [ABSTRACT FROM AUTHOR]

Introduction: Rectus abdominis diastasis (RAD) ± concomitant hernia is a complex hernia entity of growing significance in everyday clinical practice. Due to a multitude of described surgical techniques, a so far missing universally accepted classification and hardly existing comparative studies, there are no clear recommendations in guidelines. Therefore, "RAD ± concomitant hernia" will be documented as a separate hernia entity in the Herniamed Registry in the future. For this purpose, an appropriate case report form will be developed on the basis of the existing literature.Methods: A systematic search of the available literature was performed in March 2021 using Medline, PubMed, Google Scholar, Scopus, Embase, Springer Link, and the Cochrane Library. 93 publications were identified as relevant for this topic.Results: In total 45 different surgical techniques for the repair of RAD ± concomitant hernia were identified in the surgical literature. RAD ± concomitant hernia is predominantly repaired by plastic but also by general surgeons. Classification of RAD ± concomitant hernia is based on a proposal of the German Hernia Society and the International Endohernia Society. Surgical techniques are summarized as groups subject to certain aspects: Techniques with abdominoplasty, open techniques, mini-less-open and endoscopic sublay techniques, mini-less-open and endoscopic subcutaneous/preaponeurotic techniques and laparoscopic techniques. Additional data impacting the outcome are also recorded as is the case for other hernia entities. Despite the complexity of this topic, documentation of RAD ± concomitant hernia has not proved to be any more cumbersome than for any of the other hernia entities when using this classification.Conclusion: Using the case report form described here, the complex hernia entity RAD ± concomitant hernia can be recorded in a registry for proper analysis of comparative treatment options. [ABSTRACT FROM AUTHOR]

Hybrid males that inherit haploid set of chromosomes along with Hybrid male rescue, (Hmr+) gene from D. melanogaster mother and an autosomal set with Lethal hybrid rescue, (Lhr+) gene from D. simulans father, die at the larval/pupal transition phase due to insufficient growth of imaginal disc tissues. Comparable pattern reminiscent of hybrid F1female lethality was noted when D. melanogaster compound females were crossed with D. simulans males. The lethality is suppressed when the hybrids inherit one mutant allele of hybrid incompatibility gene (either Lhr−, or Hmr−) from either of the parent. In order to better understand the cause of lethality of F1 hybrids at larval stage, the imaginal discs development of lethal hybrids were examined and compared with those of 'rescued' hybrids with Lhr− and parental species. The study revealed the following major findings: (a) when hybrid male and female larvae carry only D. melanogaster X chromosome(s) in presence of both Lhr+ and Hmr+ genes, broad-ranging cell death reaction was induced in the disc tissues and eventually death of the hybrid larvae, (b) when hybrid females carry the X chromosome of both species in the background of maternal cytoplasm of D. melanogaster, the frequency of cell death in the discs was reduced significantly and discs were able to metamorphose, (c) when hybrid males and females inherit one set of autosome from Lhr null strain of D. simulans, the frequency of non-apoptotic cell death in the discs was suppressed significantly and discs development were restored, although the discs displayed fluctuating asymmetric of development. To understand the defects in the chromosomal organization associated with abnormal development of the 'rescued' hybrids, the functional organization of the polytene chromosomes of the 'rescued' hybrids were examined. It was noted that incomplete pairing of the autosomes of two species along with abnormal X chromosomal telomeric structure may have some bearing on developmental defects of the 'rescued' hybrids. From the results it is suggested that (1) cell death reaction in the imaginal discs of the larval lethal hybrids may be the result of divergent lineage of maternal and paternal sets of chromosomes in zygote in presences of two species specific mediator genes, Lhr+, and Hmr+, (2) suppression of larval lethality, in absence of Lhr function, indicated that the non-apoptotic type of cell death factor in the disc cells was controlled genetically by the two mediator genes in the disc cells, (3) re-specification of compartmental organization of paternal segment polarity genes in 'rescued' hybrid discs might cause non-random tissue damages and eventually the apoptotic type of cell death resulting into asymmetric development of the appendages in hybrids. In sum, our data revealed that cell death reaction in imaginal discs, associated with larval lethality in hybrids was a developmentally controlled program, through incompatible interactions between species specific mediator genes, Lhr+, Hmr+ and D. melanogaster X chromosome and the pattern of cell death reaction in the discs was different from apoptosis. [ABSTRACT FROM AUTHOR]

Introduction: The proportion of recurrent repairs in the total collective of inguinal hernia repairs among men is 11.3–14.3% and among women 7.0–7.4%. The rate of re-recurrences is reported to be 2.9–9.2%. To date, no case series has been published on second and ≥ third recurrences and their treatment outcomes. Only case reports are available. Materials and methods: In an analysis of data from the Herniamed Registry the perioperative and 1-year follow-up outcomes of 16,206 distinct patients who had undergone first recurrent (n = 14,172; 87.4%), second recurrent (n = 1,583; 9.8%) or ≥ third recurrent (n = 451; 2.8%) inguinal hernia repair between September 1, 2009 and July 1, 2017 were compared. Results: The intraoperative complication rate for all recurrent repairs was between 1–2%. In the postoperative complications a continuous increase was observed (first recurrence: 3.97% vs second recurrence: 5.75% vs ≥ third recurrence 8.65%; p < 0.001). That applied equally to the complication-related reoperation rates (first recurrence: 1.50% vs second recurrence: 2.21% vs ≥ third recurrence 2.66; p = 0.020). Likewise, the re-recurrence rate rose significantly (first recurrence: 1.95% vs second recurrence: 2.72% vs ≥ third recurrence 3.77; p = 0.005). Similarly, the rate of pain requiring treatment rose highly significantly with an increasing number of recurrences (first recurrence: 5.21% vs second recurrence: 6.70% vs ≥ third recurrence 10.86; p = < 0.001). Conclusion: The repair of re-recurrences in inguinal hernia is associated with increasingly more unfavorable outcomes. For the first recurrence the guidelines should definitely be noted. For a second and ≥ third recurrence diagnostic laparoscopy may help to select the best possible surgical technique. [ABSTRACT FROM AUTHOR]

Bio-composite scaffolds were fabricated by impregnating 10, 20, 30, 40 and 50% ZrO content with the β-TCP matrix to heal load bearing large size bone defects. The composite scaffolds were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and mechanical testing. The in vitro degradation of scaffolds was calculated by immersing the samples in phosphate buffer saline for a period of 21 days. Biocompatibility was evaluated by XTT assay using human Osteosarcoma cell line (MG-63). Results include scaffold surface morphology, overall porosity, phase transformation, bonding, compressive strength, biodegradability and cytotoxicity with an increase in ZrO percentages. The conclusions proved that β-TCP scaffold with 30% ZrO content exhibits the best-required properties for the application in the field of bone tissue regeneration. [ABSTRACT FROM AUTHOR]

Patient specific HA/β-TCP scaffold were fabricated using an indirect fabrication approach which involves the application of rapid prototyping technology. β-TCP powder with 10, 20 and 30 % HA concentrations were analyzed for different sintering temperatures. Scaffolds were evaluated by Scanning Electron Microscopy, X-ray diffraction, compression tests, Fourier transform infrared spectroscopy and cytotoxicity tests using human osteosarcoma cell line. Results include HA/β-TCP scaffold porosity, volumetric shrinkage, mechanical properties, bonding, structural phase change and cytotoxicity. [ABSTRACT FROM AUTHOR]

With the development of society, more and more attentions are paid to the medical equipment or devices that have much help to improve people's life quality. The use of intravenous (IV) supply bags and bottles to introduce nutrient, therapeutic and medicinal fluids into the human body is well-known in the art. Typically, such systems have a container suspended above a patient by means of an IV bag stand or the like. In the present work the authors proposed a Rapid Prototyping (RP) assisted fabrication of a simple mechanical device which can be used for medical infusion therapy in to the human body. [ABSTRACT FROM AUTHOR]

Beta Tri calcium phosphate scaffolds were produced by inverse casting methodology using rapid prototyping technology. Β-TCP scaffold sintered at different temperatures were analyzed by using Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, uniaxial compression test and cytotoxicity test. Results incorporate scaffold pore size, bonding, phase chance, porosity, mechanical strength, and cytotoxic profile with an increase in the sintering temperatures. Together, these properties are required for scaffold fabrication in the field of bone tissue regeneration. [ABSTRACT FROM AUTHOR]

Materials that are hard to manufacture with conventional manufacturing routes can be fabricated by incorporating the advanced automation. This has motivated the authors to propose a new computational methodology which could help in quantitative and qualitative manufacturing of bulk metallic glasses (BMGs). The present model was designed to propose the critical cooling rate (RC) based on glass transition temperature (Tg), onset crystallization temperature (TX) and liquidus temperature (Tl). Available correlation between RC and γm parameters has been used to validate the modeled values of Tg, TX and Tl. It was observed that obtained results have shown a close resemblance to experimental values of RC. It was found that Pd-based BMGs exhibited better correlation fit than other families of BMGs. Authors believed that this investigation will be useful for processing of bulk metallic glasses in coming days. [ABSTRACT FROM AUTHOR]

In this paper, correlation of thermal stability (ΔTx) with the bond parameters such as electronegativity (Δx), atomic radius mismatch (δ), and valence electron concentration (Δn1/3) for Mg-based multicomponent bulk metallic glasses (BMGs) have been evaluated. A statistical approach of regression analysis has been adopted to investigate correlations among these parameters. Available experimental data have been used for the systematic investigation from ternary to multicomponent Mg-based BMGs. In addition, the applicability of the criteria has been assessed for the systems with and without rare earth (RE) elements. We have found that BMG systems containing RE group elements have significant effect on width of supercooled liquid region. Results obtained from our modified empirical equation have been compared with that of earlier models and have shown better correlations. [ABSTRACT FROM AUTHOR]

Copyright of Der Chirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The guidelines of the international hernia societies recommend laparo-endoscopic inguinal hernia repair for recurrent hernias after open primary repair. To date, no randomized trials have been conducted to compare the TEP vs TAPP outcome for recurrent inguinal hernia repair. A Swiss registry study identified only minor differences between the two techniques, thus suggesting the equivalence of the two procedures.Materials and Methods: Between September 1, 2009 and August 31, 2013 data were entered into the Herniamed Registry on a total of 2246 patients with recurrent inguinal hernia repair following previous open primary operation in either TAPP (n = 1,464) or TEP technique (n = 782).Results: Univariable and multivariable analysis did not find any significant difference between TEP and TAPP with regard to the intraoperative complications, complication-related reoperations, re-recurrences, pain at rest, pain on exertion, or chronic pain requiring treatment. The only difference identified was a significantly higher postoperative seroma rate after TAPP, which was influenced by the surgical technique, previous open primary operation and EHS-classification medial and responded to conservative treatment.Conclusion: TEP and TAPP are equivalent surgical techniques for recurrent inguinal hernia repair following previous open primary operation. The choice of technique should be tailored to the surgeon's expertise. [ABSTRACT FROM AUTHOR]

Introduction: On the basis of six meta-analyses, the guidelines of the European Hernia Society (EHS) recommend laparo-endoscopic recurrent repair following previous open inguinal hernia operation and, likewise, open repair following previous laparo-endoscopic operation. So far no data are available on implementation of the guidelines or for comparison of outcomes. Besides, there are no studies for comparison of outcomes for compliance versus non-compliance with the guidelines.Patients and Methods: In total, 4812 patients with elective unilateral recurrent inguinal hernia repair in men were enrolled between September 1, 2009, and September 17, 2014, in the Herniamed Registry. Only patients with 1-year follow-up were included.Results: Out of the 2482 laparo-endoscopic recurrent repair operations 90.5% of patients, and out of the 2330 open recurrent repair procedures only 38.5% of patients, were operated on in accordance with the guidelines of the EHS. Besides, on compliance with the guidelines multivariable analysis demonstrated for laparo-endoscopic recurrent repair a significantly lower risk of pain at rest (OR 0.643 [0.476; 0.868]; p = 0.004) and pain on exertion (OR 0.679 [0.537; 0.857]; p = 0.001). Comparison of laparo-endoscopic and open recurrent repair in settings of compliance versus non-compliance with the guidelines showed a higher incidence of perioperative complications and re-recurrences for recurrent repairs that did not comply with the guidelines.Conclusion: The EHS guidelines for recurrent inguinal hernia repair are not yet being observed to the extent required. Non-compliance with the guidelines is associated with higher perioperative complication rates and higher risk of re-recurrence. Even on compliance with the guidelines, the risk of pain at rest and pain on exertion is higher after open recurrent repair than after laparo-endoscopic repair. [ABSTRACT FROM AUTHOR]

Introduction: For open and endoscopic inguinal hernia surgery, it has been demonstrated that low-volume surgeons with fewer than 25 and 30 procedures, respectively, per year are associated with significantly more recurrences than high-volume surgeons with 25 and 30 or more procedures, respectively, per year. This paper now explores the relationship between the caseload and the outcome based on the data from the Herniamed Registry.Patients and Methods: The prospective data of patients in the Herniamed Registry were analyzed using the inclusion criteria minimum age of 16 years, male patient, primary unilateral inguinal hernia, TEP or TAPP techniques and availability of data on 1-year follow-up. In total, 16,290 patients were enrolled between September 1, 2009, and February 1, 2014. Of the participating surgeons, 466 (87.6 %) had carried out fewer than 25 endoscopic/laparoscopic operations (low-volume surgeons) and 66 (12.4 %) surgeons 25 or more operations (high-volume surgeons) per year.Results: Univariable (1.03 vs. 0.73 %; p = 0.047) and multivariable analysis [OR 1.494 (1.065-2.115); p = 0.023] revealed that low-volume surgeons had a significantly higher recurrence rate compared with the high-volume surgeons, although that difference was small. Multivariable analysis also showed that pain on exertion was negatively affected by a lower caseload <25 [OR 1.191 (1.062-1.337); p = 0.003]. While here, too, the difference was small, the fact that in that group there was a greater proportion of patients with small hernia defect sizes may have also played a role since the risk in that group was higher. In this analysis, no evidence was found that pain at rest [OR 1.052 (0.903-1.226); p = 0.516] or chronic pain requiring treatment [OR 1.108 (0.903-1.361); p = 0.326] were influenced by the surgeon volume. As confirmed by previously published studies, the data in the Herniamed Registry also demonstrated that the endoscopic/laparoscopic inguinal hernia surgery caseload impacted the outcome. However, given the overall high-quality level the differences between a "low-volume" surgeon and a "high-volume" surgeon were small. That was due to the use of a standardized technique, structured training as well as continuous supervision of trainees and surgeons with low annual caseload. [ABSTRACT FROM AUTHOR]

Spigelian hernias are rare forms of abdominal hernia but can lead to severe complications. Besides conventional techniques there are only a few reports on the successful use of minimally invasive surgery (MIS) techniques. In this paper the combination of laparoscopy and TEP (total extraperitoneal patch plasty) technique without mesh fixation is presented. In our opinion laparoscopy - TEP - laparoscopy is a logical, safe and beneficial method for treatment of Spigelian hernias. [ABSTRACT FROM AUTHOR]

With increasing experience in totally extraperitoneal (TEP) hernia repair, we observed an anatomical structure not described in the literature. It is a loop-like structure under the ductus deferens or ligamentum teres uteri anchored laterally and medially to the peritoneum. Relatively constant in distance to the inner inguinal ring and individual in the grade of prominence, it inhibits correct patch placement medially. To identify and describe this so-called preperitoneal loop (pl), we performed this study. Between February 2nd and July 15th 2006, all patients undergoing a TEP procedure at our institution in primary inguinal hernia without previous operations in the lower abdomen were included. The main topic was the prominence and distance to the inner inguinal ring of the pl and histological examinations were made. A total of 219 patients (194 male, 25 female) were included, with 97 right-side, 64 left-side and 58 bilateral hernias. The pl could be shown in 206 cases (94%), the distance to the inner ring was up to 1.5 cm in 60, between 1.5 and 3.0 cm in 112, and over 3 cm in 34 cases. Anatomical examinations showed smaller blood vessels embedded in fatty tissue and surrounded by collagen fibres (standard haematoxylin eosin [HE]) and collagen connective tissue strongly filled with elastic fibres and, occasionally, nerve fibres and lymphatic capillaries (van Gieson). The pl is a very constant structure that is independent of gender and hernia type and size. In most cases, it is found close to the inner inguinal ring and, therefore, has to be cut for adequate parietalisation of cord structures/ligamentum teres uteri and correct mesh placement medially. As no mesothel was found, the origin of pl might be the deeper sheet of transversalis fascia. [ABSTRACT FROM AUTHOR]

Introduction: In the update of the guidelines of the European Hernia Society, open Lichtenstein and endoscopic techniques continue to be recommended as the surgical technique of choice for repair of unilateral primary inguinal hernias in men despite the fact that a meta-analysis had identified a higher recurrence rate for TEP compared with Lichtenstein operation. The Guidelines Group had taken that decision because one surgeon in one of the randomized controlled trials included in the meta-analysis had had a very high recurrence rate. Therefore, this study based on registry data now compares the outcome of TEP versus Lichtenstein repair.Patients and Methods: The analysis of the Herniamed Registry compares the prospective data collected for male patients undergoing primary unilateral inguinal hernia repair using either TEP or open Lichtenstein repair. Inclusion criteria were minimum age of 16 years, male patient, primary unilateral inguinal hernia, elective operation, and availability of data on 1-year follow-up. In total, 17,388 patients were enrolled between September 1, 2009, and August 31, 2013. Of these patients, 10,555 (60.70 %) had a Lichtenstein repair and 6833 (39.30 %) a TEP repair.Results: On multivariable analysis, the surgical technique was not found to have had any significant effect on the recurrence rate (p = 0.146) or on the chronic pain rate (p = 0.560). Nor did the complication-related reoperation rates differ significantly between the two techniques (p = 0.084). But TEP was found to have benefits as regards the postoperative complication rate (p < 0.001), pain at rest rate (p = 0.011), and pain on exertion rate (p < 0.001). In the present registry study, no significant difference was identified in the recurrence rates between the TEP and Lichtenstein technique. TEP was found to have benefits compared with Lichtenstein repair as regards the postoperative complication rates, pain at rest, and pain on exertion. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to evaluate the safety and efficacy of a novel 5-mm laparoscopic linear stapler in clinical gastrointestinal surgical applications.Methods: A prospective, single-arm study with an open enrollment of subjects requiring stapling of the gastrointestinal (GI) tract was performed. The study endpoints were the number of complications and technical failures associated with the use of a novel stapler when compared to similar events with conventional staplers as described in the medical literature.Results: Seven centers enrolled 160 subjects, 150 of which were followed up to at least 30 days postoperatively. Intraoperative success: In 423 deployments, there were two staple line leaks and five staple line bleeds, all of which were intraoperatively resolved. In addition, incomplete staple lines were noted as a result of user error (n = 15) or device-related issues (n = 22), all of which were immediately resolved and none of which resulted in a complication or a change of the surgical procedure. Late outcomes: A total of 13 surgical complications in 160 patients were related to a GI transection or anastomosis, 12 of which related to a hand-sewn anastomosis or use of other commercially available staplers. One event (1/153, 0.065 %) on POD 1, involving bleeding of the staple line, was felt to be related to the use of the new stapler.Conclusion: The study confirmed that the new device was user-friendly (9 % incidence of problems firing the device), reliable (3 % device failures) and safe (<1 % complication rate related to the stapler). Based on these results, it would seem that this new 5-mm stapler is a safe and effective alternative to standard 12-mm staplers. [ABSTRACT FROM AUTHOR]

Introduction: To date, there are no prospective randomized studies that compare the outcome of endoscopic repair of primary versus recurrent inguinal hernias. It is therefore now attempted to answer that key question on the basis of registry data.Patients and Methods: In total, 20,624 patients were enrolled between September 1, 2009, and April 31, 2013. Of these patients, 18,142 (88.0%) had a primary and 2482 (12.0%) had a recurrent endoscopic repair. Only patients with male unilateral inguinal hernia and with a 1-year follow-up were included. The dependent variables were intra- and postoperative complications, reoperations, recurrence, and chronic pain rates. The results of unadjusted analyses were verified via multivariable analyses.Results: Unadjusted analysis did not reveal any significant differences in the intraoperative complications (1.28 vs 1.33%; p = 0.849); however, there were significant differences in the postoperative complications (3.20 vs 4.03%; p = 0.036), the reoperation rate due to complications (0.84 vs 1.33%; p = 0.023), pain at rest (4.08 vs 6.16%; p < 0.001), pain on exertion (8.03 vs 11.44%; p < 0.001), chronic pain requiring treatment (2.31 vs 3.83%; p < 0.001), and the recurrence rates (0.94 vs 1.45%; p = 0.0023). Multivariable analysis confirmed the significant impact of endoscopic repair of recurrent hernia on the outcome.Conclusion: Comparison of perioperative and 1-year outcome for endoscopic repair of primary versus recurrent male unilateral inguinal hernia showed significant differences to the disadvantage of the recurrent operation. Therefore, endoscopic repair of recurrent inguinal hernias calls for particular competence on the part of the hernia surgeon. [ABSTRACT FROM AUTHOR]

Introduction: More than 20 years since the introduction of TAPP and TEP into clinical routine, there is a lack of clarity due to conflicting comparative data. Therefore, more results from registries are needed.Patients and Methods: A total of 17,587 patients were enrolled prospectively between September 1, 2009, and April 15, 2013, in the Herniamed registry. Of these patients, 10,887 (61.9%) had a TAPP and 6700 (38.1%) a TEP repair. The dependent variables were intra- and postoperative complication rates, number of reoperations as well as absolute and relative frequencies. The results of unadjusted analyses were verified via multivariable analyses.Results: Multivariable analysis verified the results of unadjusted analysis, indicating that the surgical technique did not have any significant impact, also while taking account of other factors, on occurrence of intraoperative [p = 0.1648; OR = 1.214 (0.923; 1.596)] and general postoperative complications [p = 0.0738; OR = 1.315 (0.974; 1.775)]. Postoperative surgical complications [OR = 2.323 (1.882; 2.866); p < 0.0001] were noted more often after TAPP. Furthermore, the hernia defect size [p < 0.0001; I vs III: OR = 0.439 (0.313; 0.615), II vs III: OR = 0.712 (0.582; 0.872)] or scrotal [p < 0.0001; OR = 2.170 (1.501; 3.137)] hernia and age [p = 0.0002; 10-year OR = 1.135 (1.062; 1.213)] had a significant impact on the occurrence of postoperative complications. Complications were observed more commonly for larger hernia defects and a scrotal hernia. However, the difference in the postoperative complication rate between TEP and TAPP did not result in any difference in the reoperation rate (TEP 0.82% vs TAPP 0.90%; p = 0.6165).Conclusion: The intraoperative and general postoperative complication rates as well as the reoperation rate for complications show no significant difference between TEP and TAPP. The higher postoperative complication rate for TAPP, which could be managed conservatively, is partly explained by larger defect sizes, more scrotal hernias and older age. [ABSTRACT FROM AUTHOR]

In Drosophila melanogaster, the intersex ( ix) is a terminally positioned gene in somatic sex determination hierarchy and function with the female specific product of double sex (DSX ) to implement female sexual differentiation. The null phenotype of ix is to transform diplo-X individuals into intersexes while leaving haplo-X animals unaffected. This study on the effect of different intersexmutations on genital disc development provides the following major results: (i) similar range of a characteristic array of morphological structures (from almost double sex terminalia to extreme reduction of terminal appendages) was displayed by the terminalia of XX ix /ix, XX ix /ix and XX ix /ix individuals; (ii) an increased number of apoptotic cells were found to occur in a localized manner in mature third instar larval genital discs of ix individuals; (iii) ix mutations can induce high frequency of neoplastic tumours in genitals in the presence of decapentaplegic ( dpp) mutations; and (iv) heteroallelic combinations of dpp mutations can also induce tumours in intersex genitals with variable expressivity. On the basis of these findings, we suggest that: (i) loss of function of ixcauses massive cell death in both male and female genital primordia of genital discs, resulting phenotype mimicking in male and female characteristics in genitals; and (ii) at the discs, the apoptotic cells persist as 'undead' cells that can induce oncogenic transformation in the neighbouring disc cells when dppsignalling is blocked or reduced by dpp mutations. [ABSTRACT FROM AUTHOR]

Background: The implantation of a polymer mesh is considered as the standard treatment for incisional hernia. It leads to lower recurrence rates compared to suture techniques without mesh implantation; however, there are also some drawbacks to mesh repair. The operation is more complex and peri-operative infectious complications are increased. Yet it is not clear to what extent a mesh implantation influences quality of life or leads to chronic pain or discomfort. The influence of the material, textile structure and size of the mesh remain unclear. The aim of this study was to evaluate if a non-absorbable, large pore-sized, lightweight polypropylene (PP) mesh leads to a better health outcome compared to a partly absorbable mesh. Methods/design: In this randomised, double-blinded study, 80 patients with incisional hernia after a median laparotomy received in sublay technique either a non-absorbable mesh (Optilene® Mesh Elastic) or a partly absorbable mesh (Ultrapro® Mesh). Primary endpoint was the physical health score from the SF-36 questionnaire 21 days post-operatively. Secondary variables were patients' daily activity score, pain score, wound assessment and post-surgical complications until 6 months post-operatively. Results: SF-36, daily activity and pain scores were similar in both groups after 21 days and 6 months, respectively. No hernia recurrence was observed during the observation period. Post-operative complication rates also showed no difference between the groups. Conclusion: The implantation of a non-absorbable, large pore-sized, lightweight PP mesh for incisional hernia leads to similar patient-related outcome parameters, recurrence and complication rates as a partly absorbable mesh. [ABSTRACT FROM AUTHOR]

Background: The young field of obesity surgery (bariatric surgery) in Germany expands as a consequence of the rapid increase of overweight and obesity. New surgical methods, minimal access techniques, and the enormous increase of scientific studies and evidence, all contribute to the success of bariatric surgery, which is the only realistic chance of permanent weight loss and regression of secondary diseases in many cases. Methods: A systematic literature review, classification of evidence, graded recommendations, and interdisciplinary consensus. Results: Obesity surgery is an integral component of the multimodal treatment of obesity, which consists of multidisciplinary evaluation and preparation, conservative and surgical treatment elements, and a life-long follow-up. The guideline confirms the body mass index (BMI)-based spectrum of indications (BMI > 40 kg/m or >35 kg/m with secondary diseases) and extends it through elimination of all age restrictions (>18 years and <60 years) and most of the contraindications. Precondition for surgery is the failure of a structured conservative program of 6-12 months or the expected futility of it. Type II diabetes mellitus becomes an independent indication criterion for BMI < 35 kg/m (metabolic surgery). The standard techniques are gastric balloon, gastric banding, gastric bypass, gastric sleeve, and biliopancreatic diversion. The choice of procedure is based on profound knowledge of results, long-term effects, complications, and patient-specific circumstances. The after-care should be structured and organized long term. Conclusion: The S3-guidelines contain evidence-based recommendations for the indication, selection of procedure, technique, and follow-up. Patient care should improve after implementation of these guidelines in clinical practice. Compliance by decision makers and health insurers is warranted. [ABSTRACT FROM AUTHOR]

Adjustable silicone gastric banding (ASGB) is an effective treatment in morbid obesity. Band migration is a long-term complication. Causes, clinical symptoms, timing and incidence are investigated in single centres only. In Germany, since January 1st, 2005, practice in bariatric surgery has been investigated in German prospective multicenter trial for quality assurance in obesity surgery. All patients underwent ASGB in two centres of bariatric surgery in Germany were prospectively registered using a computer-based data form. Patients with band migration were retrospectively evaluated, in particular, causes and characteristics of its management. The results were correlated with data obtained from the German prospective multicentre trial. In total, 493 patients were enrolled in the study from February 1995 to February 2007 . The follow-up rate was 79.9% (mean follow-up time period, 78.7 months; range, 2–148 months). Fifteen patients (3.0%) developed migration. In 14 cases, migration occurred within the range of 30–86 months after implantation. In one case, migration occurred 10 months after repositioning of the band. In the German multicentre trial, 629 patients underwent surgery during 2005 and 827 patients in 2006. In both periods, 74.4% of the patients were female and 25.6% male. The most frequently performed operation was ASGB (46.8%) followed by Roux-en-Y gastric bypass (38.5%). Band migration requires band removal. Different symptoms and complications influence the kind of band removal. Multicentre data were evident in the case of high long-term complication rate after ASGB. Data of the German multicentre trial show the trend from restrictive bariatric procedures to malabsorptive approach. [ABSTRACT FROM AUTHOR]

Background: We report on a prospective observational multicenter study of more than 1,000 consecutive patients undergoing laparoscopic colorectal procedures. The aim of the current study was to investigate the safety of laparoscopic colorectal surgery as reflected by the anastomotic insufficiency rates in the various sections of the bowel, and to compare these rates with those of open colorectal surgery.Methods: The study was begun on August 1, 1995. Twenty-four centers in Germany, Austria, and Switzerland participated in this prospective multicenter study. All patients undergoing laparoscopic colorectal surgery were included in the study. No selection criteria were applied, which means that every operation begun as a laparoscopic procedure was included. Data on patient demographics, surgical indications, surgical course, and patient outcome were recorded prospectively in a computer database. All data were rendered anonymous.Results: Between August 1995 and February 1998, the 24 participating centers treated 1,143 patients (male/female ratio, 1:1.36; mean age, 60.7 years). In all, 626 operations were performed for benign indications and 517 for cancer. Most procedures involved the sigmoid colon and rectum (80.9%). An anastomosis was performed in 83% of the operations. Most of the anastomoses were laparoscopically assisted using the stapling technique. We observed an overall leakage rate of 4.25% (colon 2.9%; rectum 12.7%), and surgical reintervention was required in 1% of the cases. The rate of conversion to open surgery was 5.6%. Intraoperative complications occurred in 5.9%, and reoperation was necessary in 4.1% of the cases. The overall morbidity rate was 22.3%, and the 30-day mortality rate was 1.57%.Conclusions: The feasibility and safety of the laparoscopic colorectal approach is demonstrated clearly. The current study shows that the laparoscopic or laparoscopically assisted approach to colorectal surgery is not associated with a higher risk of anastomotic leaks. Morbidity and mortality rates with this method approximate those seen with conventional colorectal surgery. [ABSTRACT FROM AUTHOR]

Background: In the large bowel, resection of the sigmoid colon is the most commonly performed laparoscopic intervention because large bowel lesions often are located in this part of the bowel and the procedure technically is the most favorable one. A number of publications involving case series or the results of highly experienced individual surgeons already have confirmed the feasibility of laparoscopic resection in cases of diverticulitis. The aim of the present prospective multicentric investigation was to check the results obtained by a large number of surgeons performing laparoscopic resection of the sigmoid colon for diverticulitis in various stages of severity.Results: Between January 8, 1995 and January 1, 1998, the Laparoscopic Colorectal Surgery Study Group recruited 1,118 patients to the prospective multicenter study. Diverticulitis of the sigmoid colon, which accounted for 304 cases, was the most common indication for laparoscopic intervention. In most of these patients undergoing laparoscopic surgery (81.9%), the diverticulitis manifested as acute phlegmonous peridiverticulitis, recurrent attacks of inflammation, or stenosis. Complicated forms of diverticulitis in Hinchey stages I to IV and late complications of chronic diverticular disease with fistula formation and bleeding accounted for only 18.1% of the cases. For the overall group, the conversion rate was 7.2%. Patients with less severe diverticulitis (i.e., those presenting with peridiverticulitis, stenosis, or recurrent attacks of inflammation) had a conversion rate of 4.8% and the rate for complicated cases was 18.2%. Regarding laparoscopically completed interventions, 3 of 282 patients died (1.1%). In the group of patients with peridiverticulitis, stenosis, or recurrent attacks of inflammation the overall complication rate was 14.8%. The group with perforated diverticulitis in Hinchey stages I to IV or those with fistula and bleeding, the corresponding rate was 28.9%, and after conversion it was 31.8%.Conclusions: Laparoscopic colorectal interventions in sigmoid diverticulitis are, for the most part, carried out as elective procedures for peridiverticulitis, stenosis, or recurrent attacks of inflammation. The conversion, complication, and mortality rates associated with these interventions are acceptable. Laparoscopic procedures in Hinchey stages I to IV sigmoid diverticulitis and in the presence of fistula and bleeding are more likely to be associated with complications, and should be carried out only by highly experienced laparoscopic surgeons. [ABSTRACT FROM AUTHOR]

Background: Prospective randomized multicenter studies comparing laparoscopic with open colorectal surgery are not yet available. Reliable data from prospective multicenter studies involving consecutive patients are also lacking. On the basis of the personal caseloads of specialized surgeons or of retrospective analyses, it is difficult to judge the true effectiveness of this new technique. This study aims to investigate the results of laparoscopic colorectal surgery in consecutive patients operated on by unselected surgeons.Methods: This observational study was begun August 1, 1995, in the German-speaking part of Europe (Germany and Austria) and 43 centers initially agreed to participate. All consecutive cases were documented. All data were rendered anonymous. Analysis was performed on an intention-to-treat basis. The study committee was blinded to the participating center.Results: By the end of the 1st year, 500 patients (M:F ratio 0.83, mean age 62.9 years) had been treated by 18 centers; 269 operations were performed for benign indications and 231 for cancer (palliative and curative). Most operations were done on the distal colon or rectum. An anastomosis was performed in 84%, with an overall leakage rate of 5.3% (colon 3.6% and rectum 11.8%), which required surgical reintervention in 1.7%. The mean operating time was 176 min and showed a decreasing tendency over the period under study. The conversion rate was 7.0% and the overall complication rate 21.4%. The reoperation rate was 6.6%; the most common cause was bleeding. There was one ureteral lesion (0.2%), but urinary tract infections were fairly common (4.8%). A postoperative pneumonia was diagnosed in 1.6% of the cases. No thromboembolic complications were reported. The 30-day mortality rate was 1.4% and overall hospital mortality 1.8%.Conclusions: Laparoscopic colorectal operations are still rare (about 1% of all colorectal operations in Germany). Laparoscopic procedures are more common on the left colon and rectum than on the right colon. The surgical complication rate is acceptable, comparable with rates reported by others for open surgery. Cardiopulmonary and thromboembolic complications were rarely seen. Mortality and surgical morbidity rates do not differ significantly among participating centers. A learning curve, reflected by a shortening of the operating time and a somewhat lower conversion rate, was observed over the observation period. [ABSTRACT FROM AUTHOR]

The subclavian artery pseudoaneurysm developing in a patient of axonal head injury triggered a search for possible causative factor. Intimacy between the aneurysm and the tracheostomy tube suggested possibility of constant irritation of subclavian artery by the tube leading to pseudoaneurysm. The hypothesis is supported by the short neck, long uncuffed tube and constant posture of the neck with absence of any other causative factor. Pseudoaneurysm was repaired without reconstruction of subclavian artery considering well developed collaterals. [ABSTRACT FROM AUTHOR]

We report a case of an elderly man who suffered an acute myocardial infarction (MI) with the complication of a post-MI ventricular septal defect (VSD). Situs inversus with dextrocardia was diagnosed during the course of hospitalization. Total myocardial revascularization was achieved using saphenous vein conduits. The VSD was approached through the right ventricle and repaired with a polytetrafluoroethylene patch. Although several cases of coronary artery bypass grafting (CABG) in the presence of dextrocardia have been reported in the literature, this is the first case of repair of a post-MI VSD along with CABG. [ABSTRACT FROM AUTHOR]