26 results on '"Megerian CA"'
Search Results
2. Cochlear implantation outcomes in patients with autoimmune and immune-mediated inner ear disease.
- Author
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Aftab S, Semaan MT, Murray GS, and Megerian CA
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- 2010
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3. Contemporary perspectives on the pathophysiology of Meniere's disease: implications for treatment.
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Semaan MT and Megerian CA
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- 2010
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4. Vestibular evoked myogenic potentials in normal mice and Phex mice with spontaneous endolymphatic hydrops.
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Sheykholeslami K, Megerian CA, Zheng QY, Sheykholeslami, Kianoush, Megerian, Cliff A, and Zheng, Qing Y
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- 2009
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5. Current assessment and management of glomus tumors.
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Semaan MT and Megerian CA
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- 2008
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6. The basic science of Meniere's disease and endolymphatic hydrops.
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Semaan MT, Alagramam KN, Megerian CA, Semaan, Maroun T, Alagramam, Kumar N, and Megerian, Cliff A
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- 2005
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7. Temporal bone fractures: otic capsule sparing versus otic capsule violating clinical and radiographic considerations.
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Dahiya R, Keller JD, Litofsky NS, Bankey PE, Bonassar LJ, and Megerian CA
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- 1999
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8. Bilateral Sequential Cochlear Implantation in Patients With Enlarged Vestibular Aqueduct (EVA) Syndrome.
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Manzoor NF, Wick CC, Wahba M, Gupta A, Piper R, Murray GS, Otteson T, Megerian CA, and Semaan MT
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- Adolescent, Child, Child, Preschool, Cochlear Implantation adverse effects, Cochlear Implants, Female, Hearing, Hearing Tests, Humans, Intraoperative Complications epidemiology, Male, Postoperative Complications epidemiology, Retrospective Studies, Syndrome, Treatment Outcome, Vestibular Aqueduct surgery, Cochlear Implantation methods, Hearing Loss, Sensorineural surgery, Vestibular Aqueduct abnormalities
- Abstract
Objectives: To analyze audiometric outcomes after bilateral cochlear implantation in patients with isolated enlarged vestibular aqueduct (EVA) syndrome and associated incomplete partition (IP) malformations. Secondary objective was to analyze rate of cerebrospinal fluid (CSF) gusher in patients with IP-EVA spectrum deformities and compare this with the existing literature., Study Design: Retrospective chart review., Methods: Thirty-two patients with EVA syndrome who received unilateral or bilateral cochlear implants between June 1999 and January 2014 were identified in the University Hospitals Case Medical Center cochlear implant database. Isolated EVA (IEVA) and Incomplete Partition Type II (IP-II) malformations were identified by reviewing high-resolution computed tomography (HRCT) imaging. Demographic information, age at implantation, surgical details, postimplantation audiometric data including speech reception thresholds (SRT), word, and sentence scores were reviewed and analyzed. Intra- and postoperative complications were analyzed as well and compared with the literature., Results: Seventeen patients (32 implanted ears) had pediatric cochlear implantation for EVA-associated hearing loss. Data from 16 controls (32 implanted ears) were used to compare audiometric and speech outcomes of EVA cohort. Mean age at implantation was 6.8 years for EVA cohort and 6.0 years for controls. There was no statistically significant difference in long-term postoperative SRT, monaurally aided word scores, and binaurally tested word scores between pediatric EVA group and controls. The EVA patients had a long-term mean sentence score of 85.92%. A subset of EVA patients implanted at mean age of 3.18 years (n = 15 ears) had similar audiometric outcomes to another control group with Connexin 26 mutations (n = 20 ears) implanted at a similar age. Further subset analysis revealed no significant differences in age at implantation, SRT, and word scores in patients with IEVA and IP-II malformation. There was no significant association between size of vestibular aqueduct and age at implantation. There was no CSF gusher or other intra- or postoperative complications reported in our series., Conclusion: Bilateral sequential cochlear implantation can be performed safely in patients with EVA. Audiometric outcomes are excellent and comparable to pediatric cochlear implant patients with no malformations. CSF gusher rates can be minimized by trans-round window approach. Further long-term studies are needed to identify differences within IP-EVA spectrum deformities, audiometric outcomes, and proportions of EVA patients who will need cochlear implantation for hearing rehabilitation.
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- 2016
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9. Characterization of neuronal cell death in the spiral ganglia of a mouse model of endolymphatic hydrops.
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Semaan MT, Zheng QY, Han F, Zheng Y, Yu H, Heaphy JC, and Megerian CA
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- Animals, Caspase 3 metabolism, Caspase 8 metabolism, Caspase 9 metabolism, Disease Models, Animal, Disease Progression, Endolymphatic Hydrops metabolism, Male, Mice, Neurons metabolism, Spiral Ganglion metabolism, Apoptosis physiology, Endolymphatic Hydrops pathology, Neurons pathology, Spiral Ganglion pathology
- Abstract
Hypothesis: Spiral ganglion neurons (SGN) in the Phex male mouse, a murine model of postnatal endolymphatic hydrops (ELH) undergo progressive deterioration reminiscent of human and other animal models of ELH with features suggesting apoptosis as an important mechanism., Background: Histologic analysis of the mutant's cochlea demonstrates ELH by postnatal Day (P) 21 and SGN loss by P90. The SGN loss seems to occur in a consistent topographic pattern beginning at the cochlear apex., Methods: SGN were counted at P60, P90, and P120. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative PCR, and immunohistochemical analyses of activated caspase-3, caspase-8, and caspase-9 were performed on cochlear sections obtained from mutants and controls. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling assay (TUNEL) was carried out on 2 mutants and 2 controls., Results: Corrected SGN counts in control mice were greater in the apical turn of the cochleae at P90 and P120, respectively (p < 0.01). Increased expression of activated caspase-3, caspase-8, and caspase-9 was seen in the mutant. At later time points, activated caspase expression gradually declined in the apical turns and increased in basal turns of the cochlea. Quantitative and semiquantitative PCR analysis confirmed increased expression of caspase-3, caspase-8, and caspase-9 at P21 and P40. TUNEL staining demonstrated apoptosis at P90 in the apical and basal turns of the mutant cochleae., Conclusion: SGN degeneration in the Phex /Y mouse seems to mimic patterns observed in other animals with ELH. Apoptosis plays an important role in the degeneration of the SGN in the Phex male mouse.
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- 2013
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10. Re: Cochlear implantation for hearing loss associated with bilateral endolymphatic sac tumors in von Hippel-Lindau disease.
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Torres JI and Megerian CA
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- Cochlear Implants, Ear Neoplasms etiology, Hearing Loss, Bilateral etiology, Humans, Terminology as Topic, von Hippel-Lindau Disease complications, Cochlear Implantation, Ear Neoplasms pathology, Endolymphatic Sac pathology, Hearing Loss, Bilateral surgery, von Hippel-Lindau Disease pathology
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- 2007
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11. Molecular changes associated with the endolymphatic hydrops model.
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Anne S, Kisley LB, Tajuddin ST, Leahy P, Alagramam KN, and Megerian CA
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- Amino Acid Transport System X-AG biosynthesis, Amino Acid Transport System X-AG genetics, Animals, Caspase 3 biosynthesis, Caspase 3 genetics, Cochlea chemistry, Endolymphatic Hydrops enzymology, Endolymphatic Hydrops genetics, Female, Glutamate-Ammonia Ligase biosynthesis, Glutamate-Ammonia Ligase genetics, Glutamic Acid metabolism, Guinea Pigs, Nitric Oxide Synthase Type I biosynthesis, Nitric Oxide Synthase Type I genetics, RNA, Messenger biosynthesis, RNA, Messenger genetics, Reverse Transcriptase Polymerase Chain Reaction, Up-Regulation physiology, Endolymphatic Hydrops metabolism
- Abstract
Hypothesis: Hearing loss and cochlear degeneration in the guinea pig model of endolymphatic hydrops (ELH) results, in part, from toxic levels of excitatory amino acids (EAAs) such as glutamate, which in turn leads to changes in the expression of genes linked to intracellular glutamate homeostasis and apoptosis, leading to neuronal cell death., Background: EAAs have been shown to play a role in normal auditory signal transmission in mammalian cochlea, but have also been implicated in neurotoxicity when levels are elevated. Changes in the expression of specific genes involved in the glutamatergic and apoptotic pathway would serve as evidence for excitotoxicity linked to elevated levels of glutamate., Methods: Guinea pigs underwent surgical obliteration of the endolymphatic duct, and then a timed harvest of the treated (right) and control (left) cochlea and subsequent quantification of gene expression via real-time quantitative polymerase chain reaction., Results: Quantitative polymerase chain reaction data show significant upregulation of glutamate aspartate transporter and neuronal nitric oxide synthase mRNA levels 3 weeks postsurgery and Caspase 3 mRNA levels 1 week postsurgery. No significant changes were detected in glutamine synthetase expression levels., Conclusion: Upregulation of genes involved in glutamate homeostasis and the apoptotic pathway in animals treated with endolymphatic duct obstruction (usually associated with secondary ELH) support the hypothesis that EAAs may play a role in the pathophysiology of ELH-related cochlear injury. Inhibitors to these pathways can be useful for the study of new avenues to delay or prevent ELH-related hearing loss.
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- 2007
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12. Optimization of ribonucleic acid detection from archival Guinea pig temporal bone specimens.
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Hall KL, Pitts DR, Anne S, Semaan MT, Alagramam KN, and Megerian CA
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- Animals, Biological Specimen Banks, DNA Primers genetics, DNA, Complementary genetics, Ear, Inner metabolism, Ear, Inner pathology, Endolymphatic Hydrops genetics, Endolymphatic Hydrops metabolism, Endolymphatic Hydrops pathology, Excitatory Amino Acid Transporter 1 genetics, Gene Expression genetics, Glutamic Acid genetics, Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+) genetics, Guinea Pigs, RNA, Messenger genetics, Reverse Transcriptase Polymerase Chain Reaction, RNA genetics, RNA metabolism, Temporal Bone metabolism, Temporal Bone pathology
- Abstract
Hypothesis: The choice of ribonucleic acid (RNA) isolation protocol coupled with modifications to RNA extraction and detection procedures may result in a more reliable method to detect gene expression in archived temporal bones., Background: A large number of archival temporal bones exist. Retrospective analysis of these specimens using techniques of RNA extraction will greatly enrich our understanding of the pathophysiology of specific otologic diseases. However, archival human temporal bones are aged and embedded in paraffin or celloidin, rendering isolation and manipulation of nucleic acid in preserved specimens difficult, especially as it pertains to RNA degradation. Despite some reports of moderate success in the recent past, RNA isolation and gene expression using polymerase chain reaction (PCR) analysis continues to be challenging and unreliable. Archival guinea pig temporal bone specimens were used to develop and optimize a protocol for RNA extraction and gene expression analysis using PCR and quantitative PCR methods. The genes amplified comprise housekeeping genes and genes associated with the glutamate pathway., Methods: Archival celloidin-embedded guinea pig temporal bones were collected from the senior author's collection of experimental hydropic inner ear specimens. RNA from this tissue was extracted using the protocol described previously in 16animals and using a modified trizol extraction technique in 10 animals. Gene expression analysis was performed on the extracted RNA. Analysis included two housekeeping genes, GAPDH and 18S, as well as three mediators of the glutamate pathway, glutamate aspartate transporter, glutamate synthetase, and inducible nitric oxide synthase., Results: Compared with the standard extraction protocol, the trizol-based extraction technique showed greater reliability and reproducibility of RNA detection. The housekeeping gene GAPDH or 18S was detected in 7 of 36 attempts with the standard protocol versus 9 of 9 using the modified extraction method (P < 0.001). The gene of interest, glutamate aspartate transporter, was detected in 3 of 26 attempts with the standard protocol versus 12 of 13 attempts using the modified extraction method (P < 0.001). Quantification of messenger RNA levels was then achieved using quantitative PCR methods., Conclusion: Improved reliability for detection of gene expression and demonstration of reproducibility were accomplished by modification of RNA extraction technique and standard reverse transcriptase PCR protocol. In addition, we also showed that gene expression from archival material can be quantified by real-time PCR.
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- 2007
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13. Treatment of glomus jugulare tumors in patients with advanced age: planned limited surgical resection followed by staged gamma knife radiosurgery: a preliminary report.
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Willen SN, Einstein DB, Maciunas RJ, and Megerian CA
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- Aged, Ambulatory Surgical Procedures, Combined Modality Therapy, Female, Follow-Up Studies, Glomus Jugulare Tumor diagnosis, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Middle Aged, Neoplasm, Residual diagnosis, Reoperation, Retrospective Studies, Tinnitus diagnosis, Tinnitus etiology, Tinnitus surgery, Treatment Outcome, Glomus Jugulare Tumor surgery, Neoplasm, Residual surgery, Radiotherapy
- Abstract
Objective: To minimize treatment comorbidities in glomus jugulare tumor patients with advanced age while reducing pulsatile tinnitus and preserving or improving residual hearing using a limited middle ear/mastoid tumor resection and postoperative gamma knife radiosurgery to tumor remnants in the jugular foramen region., Study Design: Retrospective consecutive case review of five patients., Setting: Tertiary referral, academic medical center., Patients: Patients with advanced age (mean, 69.6 yr; range, 61-78 yr) harboring symptomatic glomus jugulare tumors., Intervention: All patients were treated with resection of middle ear and mastoid portions of tumor and subsequent gamma knife radiosurgery to jugular foramen portion of tumor., Main Outcome Measures: Length of hospitalization; hearing, pulsatile tinnitus, cranial nerve, and tumor control status., Results: All patients were treated on an outpatient surgical basis without the need for blood transfusion. There were no incidents of a change in cranial nerve status (Cranial Nerves VII, IX, X, XI, and XII) in the immediate postoperative period. All patients had improvement or resolution of pulsatile tinnitus with preservation or improvement of preoperative hearing levels. Tumor volume was stable or reduced in all patients at mean follow-up of 19 months (range, 11-24 mo). Gamma knife radiosurgery (mean peripheral dose of 15 Gy) was not associated with any significant immediate or delayed complications., Conclusion: Short-term data reveals that staged microsurgical and radiosurgical therapy for glomus jugulare tumors in the symptomatic patient with advanced age is safe and yields favorable results regarding tinnitus, hearing, and cranial nerve status. Long-term data are needed to further evaluate the effectiveness of this treatment algorithm before extrapolating this treatment option to younger patients.
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- 2005
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14. Differential grading of endolymphatic sac tumor extension by virtue of von Hippel-Lindau disease status.
- Author
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Bambakidis NC, Megerian CA, and Ratcheson RA
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- Adenocarcinoma, Papillary surgery, Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, Ear Neoplasms surgery, Endolymphatic Sac diagnostic imaging, Endolymphatic Sac surgery, Female, Hearing Loss, Humans, Intracranial Hypertension, Magnetic Resonance Imaging, Male, Middle Aged, Retrospective Studies, Sex Factors, Tomography, X-Ray Computed, von Hippel-Lindau Disease diagnosis, Adenocarcinoma, Papillary complications, Adenocarcinoma, Papillary pathology, Ear Neoplasms complications, Ear Neoplasms pathology, Endolymphatic Sac pathology, von Hippel-Lindau Disease complications
- Abstract
Objective: Endolymphatic sac tumors are aggressive papillary tumors of the temporal bone frequently associated with von Hippel-Lindau disease. The goal of this study was to use a newly devised classification system as a means to analyze differences between endolymphatic sac tumor extension in von Hippel-Lindau disease and non-von Hippel-Lindau disease patients., Methods: Previously reported cases of endolymphatic sac tumor and two new cases were retrospectively reviewed and assigned to a new classification system consisting of four grades based on tumor extent and location., Results: Mean age of 103 patients without von Hippel-Lindau disease was 52.5 years, whereas in 46 patients with VHL the mean age was 31.3 years. Patients with von Hippel-Lindau disease were more likely to be female (female-to male ratio of 2:1 for von Hippel-Lindau disease patients versus 1:1 for non-von Hippel-Lindau disease patients). Symptoms consisted of hearing loss (100% [mean duration, 10 yr] for VHL patients versus 97% [mean duration, 7.8 yr] for non-von Hippel-Lindau disease patients), facial weakness (38% versus 49%), and tinnitus or vertigo (41% versus 60%). Bilateral tumors were common in von Hippel-Lindau disease patients (28% versus 1%). Tumors in von Hippel-Lindau disease patients were significantly more likely to be lower grade than tumors in non-von Hippel-Lindau disease patients (Grade I, 40% versus 25%; Grade II, 50% versus 58%; Grade III, 8% versus 14%; and Grade IV, 2% versus 4%; p < 0.05). Before 1988, there were relatively fewer Grade I (15% versus 33%) and relatively more Grade II (69% versus 47%) endolymphatic sac tumors in non-von Hippel-Lindau disease patients than after 1988., Conclusions: Increased usefulness of intracranial imaging since 1988 has led to the diagnosis of sporadic endolymphatic sac tumors with lower grades. Surveillance imaging in von Hippel-Lindau disease may account for the greater proportion of endolymphatic sac tumors diagnosed with lower grades. Endolymphatic sac tumors associated with a diagnosis of von Hippel-Lindau disease appear to affect a younger population of patients than non-von Hippel-Lindau disease cases and occur in women twice as often as in men when associated with von Hippel-Lindau disease. In addition, tumors are more frequently bilateral and less advanced in the von Hippel-Lindau disease patient as opposed to the non-von Hippel-Lindau disease patient.
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- 2004
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15. Cochlear implantation in a patient with neurofibromatosis type 1 and profound hearing loss: evidence to support a cochlear site of lesion.
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Poissant SF, Megerian CA, and Hume D
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- Adult, Brain Stem physiopathology, Cochlear Nerve physiopathology, Deafness physiopathology, Evoked Potentials, Auditory, Brain Stem physiology, Follow-Up Studies, Humans, Male, Postoperative Complications physiopathology, Reaction Time physiology, Speech Reception Threshold Test, Treatment Outcome, Cochlear Implantation, Deafness rehabilitation, Neurofibromatosis 1 surgery, Postoperative Complications etiology
- Abstract
Objective: To determine the efficacy of cochlear implantation in an individual with neurofibromatosis type 1 and profound hearing loss and to determine, to the extent possible in a living subject, the site of lesion of the hearing loss in an individual with neurofibromatosis type 1., Study Design: Postoperative assessment of an adult male with neurofibromatosis type 1., Setting: The study was completed in the Departments of Otolaryngology and Audiology, University of Massachusetts Medical Center, Massachusetts., Patients: One adult male with neurofibromatosis type 1 and bilateral, chiefly profound, sensorineural hearing loss., Interventions: The subject underwent cochlear implantation as treatment of bilateral, chiefly profound sensorineural hearing loss., Main Outcome Measures: Outcome measures include results of electrical auditory brainstem response testing, electrical compound action potential measures, and speech recognition scores., Results: Results of testing revealed expected latencies of waves II, III, and V of the electrical auditory brainstem response, measurable compound action potentials across virtually the entire length of the electrode array, and high levels of open-set, auditory-only speech understanding., Conclusions: This is the first case report describing the outcome of cochlear implantation in a patient with neurofibromatosis type 1. Composite test results support the absence of VIIIth nerve degeneration or other anomalies, indicating a cochlear site of lesion for the hearing loss in this patient. Based on the results of this investigation, standard cochlear implantation should be considered a viable option and the first line of therapy for the treatment of bilateral, severe to profound sensorineural hearing loss in patients with neurofibromatosis type 1 and normal, VIIIth nerve radiographic findings.
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- 2003
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16. Correlation between hearing loss and scala media area in guinea pigs with long-standing endolymphatic hydrops.
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Hott ME, Graham M, Bonassar LJ, and Megerian CA
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- Animals, Auditory Threshold physiology, Brain Stem physiopathology, Cochlear Duct pathology, Disease Progression, Endolymphatic Hydrops pathology, Evoked Potentials, Auditory, Brain Stem physiology, Female, Guinea Pigs, Hearing Loss, High-Frequency pathology, Hearing Loss, Sensorineural pathology, Pitch Discrimination physiology, Cochlear Duct physiopathology, Endolymphatic Hydrops physiopathology, Hearing Loss, High-Frequency physiopathology, Hearing Loss, Sensorineural physiopathology
- Abstract
Hypothesis: Histologic analysis of the hydropic and normal guinea pig cochleae was undertaken to assess a potential correlation between the magnitude of endolymphatic hydrops and hearing loss. It was hypothesized that a greater correlation than previously reported might be found by looking at long-standing endolymphatic hydrops and high-frequency range hearing., Background: Surgically induced endolymphatic hydrops in guinea pigs is the most widely used animal model for the study of human Ménière's Disease and recapitulates both endolymphatic hydrops and progressive sensorineural hearing loss. A strong correlation between the magnitude of hydrops and severity of hearing loss has been reported in the human condition, but not in the animal model., Methods: Nine albino guinea pigs were each subjected to surgical obstruction of the endolymphatic sac and duct of the right ear. The left ears remained as internal histologic controls. Hearing was assessed from 2 kHz to 32 kHz by auditory brain stem response testing for 16 to 25 weeks after surgery. Histologic morphometry after the animals were killed was used to quantify both turn-specific and weighted overall hydrops. These measures were correlated with hearing loss in each animal at all tested frequencies., Results: A statistically significant correlation between the magnitude of hydrops and the severity of hearing loss was observed for 2 kHz and 16 kHz. These frequencies correlated with both turn-specific hydrops and overall hydrops. However, turn-specific hydrops did not reliably correlate with the magnitude of hearing loss at anatomically appropriate frequency ranges. Where such a correlation did exist, it might well have been simply part of an expression of an overall correlation between hydrops and hearing loss., Conclusions: There may be a greater correlation between hydrops and hearing loss in guinea pigs with long-standing surgically induced hydrops than has previously been reported in animals with less advanced disease. These findings help to validate continued use of the model for hearing loss related to Ménière's Disease, verify the rationale of treatment modalities aimed at reducing hydrops in the human condition, and may indicate that efforts at reducing hydrops in such patients has benefits toward long-term hearing preservation.
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- 2003
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17. Hearing preservation surgery for small endolymphatic sac tumors in patients with von Hippel-Lindau syndrome.
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Megerian CA, Haynes DS, Poe DS, Choo DI, Keriakas TJ, and Glasscock ME 3rd
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- Adult, Audiometry, Ear Neoplasms complications, Ear Neoplasms physiopathology, Female, Hearing, Hearing Loss, Sensorineural diagnosis, Hearing Loss, Sensorineural etiology, Hearing Loss, Sensorineural physiopathology, Humans, Magnetic Resonance Imaging, Male, Otologic Surgical Procedures, Retrospective Studies, Tomography, X-Ray Computed, Vestibular Diseases complications, Vestibular Diseases physiopathology, Ear Neoplasms etiology, Ear Neoplasms surgery, Endolymphatic Sac surgery, Hearing Loss, Sensorineural prevention & control, Vestibular Diseases etiology, Vestibular Diseases surgery, von Hippel-Lindau Disease complications
- Abstract
Objective: To determine the incidence of bilateral endolymphatic sac tumors in von Hippel-Lindau syndrome and to describe the technique and results of hearing preservation surgery for small endolymphatic sac tumors in a series of patients with von Hippel-Lindau syndrome., Study Design: Analysis of the literature to determine the incidence of bilateral endolymphatic sac tumors and a retrospective case review of hearing preservation surgery for removal of small endolymphatic sac tumors in four patients with von Hippel-Lindau syndrome., Setting: Tertiary care academic medical centers., Patients: Four patients with von Hippel-Lindau syndrome (three with bilateral endolymphatic sac tumors) and progressive sensorineural hearing loss in which preoperative imaging studies revealed in situ or small endolymphatic sac tumors without ipsilateral labyrinthine destruction., Intervention: All four patients had complete surgical excisions of the endolymphatic sac tumor via one of three surgical approaches with the goal of hearing preservation. One patient had bilateral surgery., Main Outcome Measures: Audiometric and radiographic., Results: Nearly one-third (30.2%) of patients with von Hippel-Lindau syndrome and endolymphatic sac tumors have bilateral disease. All four patients (five ears) maintained serviceable hearing postoperatively after surgical excision of the endolymphatic sac tumor via a variety of approach options., Conclusion: The discovery of a small or in situ endolymphatic sac tumor affords the patient the option of surgical removal with hearing preservation. This is critical in the patient with von Hippel-Lindau syndrome who is at risk for bilateral disease and complete bilateral anacusis if tumor growth progresses.
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- 2002
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18. Selective retrosigmoid vestibular neurectomy without internal auditory canal drill-out: an anatomic study.
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Megerian CA, Hanekamp JS, Cosenza MJ, and Litofsky NS
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- Aged, Aged, 80 and over, Cerebellopontine Angle anatomy & histology, Cochlear Nerve anatomy & histology, Feasibility Studies, Female, Humans, Male, Middle Aged, Vestibular Nerve anatomy & histology, Cochlear Nerve surgery, Ear, Inner anatomy & histology, Otorhinolaryngologic Surgical Procedures methods, Vestibular Nerve surgery
- Abstract
Objective: It is well established that selective vestibular nerve section by means of the retrosigmoid or posterior fossa approach can be accomplished with or without drill-out of the internal auditory canal (IAC) by virtue of the presence or absence of a surgically accessible cleavage plane between the vestibular and cochlear nerves. Some reports have indicated that a majority of patients would be amenable to successful separation of the vestibular nerve from the cochlear nerve medial to the IAC, thus obviating the need for IAC drill-out and associated complications. However, other reports have indicated routine difficulty in finding a satisfactory vestibulocochlear cleavage plane within the cerebellopontine angle. This in situ cadaver study was undertaken to determine whether normal anatomic relationships support the hypothesis that selective vestibular nerve section can be accomplished by means of the posterior fossa approach without the need for concomitant IAC drill-out in a majority of circumstances., Methods: A retrosigmoid approach to the posterior fossa was performed bilaterally on 36 intact human cadavers. After displacement of the cerebellum, an operating surgical microscope was used to visualize the cerebellopontine angle in the surgical position. The ability to develop a satisfactory cleavage plane between the vestibular and cochlear nerves without the need for drill-out of the IAC was established in each case., Results: Seventy-two vestibulocochlear nerve bundles in 36 intact human cadavers were analyzed. A vestibulocochlear nerve cleavage plane within the cerebellopontine angle amenable to neurectomy medial to the porus of the IAC was observed in 81% left and 69% right vestibulocochlear nerve bundles (average, 75%). The facial nerve was found deep or anterior to the vestibulocochlear nerve bilaterally in all cases examined. The anterior inferior cerebellar artery, or a branch of the artery, was found to cross the plane between the facial and vestibulocochlear nerve bundles within the lateral cerebellopontine angle in 47% of the cases on the left and in 50% of cases on the right., Conclusions: A vestibulocochlear nerve cleavage plane amenable for selective vestibular nerve transection without drilling the IAC was found in 75% of the 72 cerebellopontine angles studied. The facial nerve consistently lies deep or anterior to the vestibulocochlear nerve within the cerebellopontine angle with the retrosigmoid approach. These findings support the rational and feasibility of avoiding drill-out of the IAC in the majority of circumstances when performing selective vestibular neurectomy by means of the posterior fossa approach for Ménière's syndrome and other vestibular disorders.
- Published
- 2002
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19. Hearing rehabilitation using the BAHA bone-anchored hearing aid: results in 40 patients.
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Lustig LR, Arts HA, Brackmann DE, Francis HF, Molony T, Megerian CA, Moore GF, Moore KM, Morrow T, Potsic W, Rubenstein JT, Srireddy S, Syms CA 3rd, Takahashi G, Vernick D, Wackym PA, and Niparko JK
- Subjects
- Acoustic Stimulation instrumentation, Adult, Aged, Aged, 80 and over, Bone Conduction physiology, Equipment Design, Female, Hearing Loss, Conductive physiopathology, Humans, Male, Middle Aged, Postoperative Care, Preoperative Care, Retrospective Studies, Hearing Aids, Hearing Loss, Conductive rehabilitation
- Abstract
Objective: This study evaluates the U.S. experience with the first 40 patients who have undergone audiologic rehabilitation using the BAHA bone-anchored hearing aid., Study Design: This study is a multicenter, nonblinded, retrospective case series., Setting: Twelve tertiary referral medical centers in the United States., Patients: Eligibility for BAHA implantation included patients with a hearing loss and an inability to tolerate a conventional hearing aid, with bone-conduction pure tone average levels at 60 dB or less at 0.5, 1, 2, and 4 kHz., Intervention: Patients who met audiologic and clinical criteria were implanted with the Bone-Anchored Hearing Aid (BAHA, Entific Corp., Gothenburg, Sweden)., Main Outcome Measures: Preoperative air- and bone-conduction thresholds and air-bone gap; postoperative BAHA-aided thresholds; hearing improvement as a result of implantation; implantation complications; and patient satisfaction., Results: The most common indications for implantation included chronic otitis media or draining ears (18 patients) and external auditory canal stenosis or aural atresia (7 patients). Overall, each patient had an average improvement of 32+/-19 dB with the use of the BAHA. Closure of the air-bone gap to within 10 dB of the preoperative bone-conduction thresholds (postoperative BAHA-aided threshold vs. preoperative bone-conduction threshold) occurred in 32 patients (80%), whereas closure to within 5 dB occurred in 24 patients (60%). Twelve patients (30%) demonstrated 'overclosure' of the preoperative bone-conduction threshold of the better hearing ear. Complications were limited to local infection and inflammation at the implant site in three patients, and failure to osseointegrate in one patient. Patient response to the implant was uniformly satisfactory. Only one patient reported dissatisfaction with the device., Conclusions: The BAHA bone-anchored hearing aid provides a reliable and predictable adjunct for auditory rehabilitation in appropriately selected patients, offering a means of dramatically improving hearing thresholds in patients with conductive or mixed hearing loss who are otherwise unable to benefit from traditional hearing aids.
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- 2001
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20. Ganglionic hamartoma of the intracanalicular acoustic nerve causing sensorineural hearing loss.
- Author
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Hung TY, Litofsky NS, Smith TW, and Megerian CA
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- Adult, Audiometry, Female, Ganglia, Hamartoma complications, Hamartoma surgery, Hearing Loss, Sensorineural diagnosis, Humans, Magnetic Resonance Imaging, Speech Discrimination Tests, Vestibulocochlear Nerve surgery, Vestibulocochlear Nerve Diseases complications, Vestibulocochlear Nerve Diseases pathology, Vestibulocochlear Nerve Diseases surgery, Hamartoma pathology, Hearing Loss, Sensorineural etiology, Vestibulocochlear Nerve pathology
- Abstract
Objective: This article highlights the clinical presentation and treatment issues of ganglionic hamartoma of the internal auditory canal and emphasizes the similarity of this lesion to acoustic neuroma regarding its audiologic and radiographic characteristics., Study Design: This article is composed of case reports and a literature review., Setting: The study was performed at a university hospital/tertiary referral center., Patient: A patient with biopsy-proven ganglionic hamartoma of the acoustic nerve was studied., Intervention: Intervention consisted of surgical therapy., Main Outcome Measure: The main outcome measure was clinical evaluation., Results: The result was successful removal of lesions with facial nerve preservation., Conclusions: An intracanalicular ganglionic hamartoma resulted in progressive sensorineural hearing loss and magnetic resonance imaging findings suggestive of small acoustic neuroma. This lesion, composed of an admixture of ganglion cells, fibroadipose-tissue, and normal myelinated axons, although rare, should be added to the differential diagnosis of internal auditory canal lesions.
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- 1997
21. The subtemporal-transpetrous approach for excision of petroclival tumors.
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Megerian CA, Chiocca EA, McKenna MJ, Harsh GF 4th, and Ojemann RG
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- Adult, Cerebellar Neoplasms pathology, Cerebellar Neoplasms surgery, Cerebellopontine Angle pathology, Cerebellopontine Angle surgery, Child, Craniotomy, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Occipital Bone, Temporal Bone surgery, Chondrosarcoma pathology, Chondrosarcoma surgery, Chordoma pathology, Chordoma surgery, Meningioma pathology, Meningioma surgery, Neurilemmoma pathology, Neurilemmoma surgery, Petrous Bone pathology, Petrous Bone surgery, Skull Neoplasms pathology, Skull Neoplasms surgery
- Abstract
The subtemporal transpetrous approach to the petroclival region uses a combination of techniques, including a petrosectomy and a subtemporal and suboccipital craniotomy. Ligation of the greater petrosal sinus, sigmoid sinus, and retraction of the temporal lobe affords wide exposure to the petroclival region and ventral brainstem and minimizes the need for facial nerve translocation. This approach has been successfully used in the management of 10 large tumors of the region, including chondrosarcomas, chordomas, meningiomas, and schwannomas. The history and evolution of this technique and its relation to other similar approaches is discussed.
- Published
- 1996
22. Delayed facial paralysis after acoustic neuroma surgery: factors influencing recovery.
- Author
-
Megerian CA, McKenna MJ, and Ojemann RG
- Subjects
- Adult, Cranial Nerve Neoplasms pathology, Facial Nerve physiopathology, Facial Paralysis physiopathology, Female, Humans, Male, Neuroma, Acoustic pathology, Retrospective Studies, Severity of Illness Index, Vestibulocochlear Nerve pathology, Cranial Nerve Neoplasms surgery, Facial Paralysis etiology, Neuroma, Acoustic surgery, Postoperative Complications, Vestibulocochlear Nerve surgery
- Abstract
Patients with satisfactory facial nerve function [House-Brackmann (HB) grade I or II] immediately after acoustic neuroma surgery are at risk for delayed facial paralysis. To study this problem, 255 consecutive patients who underwent acoustic neuroma excision with facial nerve preservation were identified. Delayed facial paralysis occurred in 62 (24.3%) patients; 90% ultimately recovered to their initial postoperative HB grade, and 98.3% recovered to within one grade of their initial HB level. Paralysis occurred at an average of 3.65 postoperative days (range, 1-16 days). The average time to maximal recovery for those with changes of 1, 2, 3, and 4 HB grades was 5.6, 21.5, 39.8, and 50.5 weeks, respectively. The early onset of paralysis (< 48 h after surgery) resulted in shorter average recovery times. Of patients who demonstrated nerve deterioration to grades IV-VI, 20 of 38 required tarsorrhaphy or gold-weight placement. We conclude that the over-whelming majority of patients with delayed facial paralysis after acoustic neuroma surgery do eventually recover to their postoperative HB grade. The magnitude and timecourse of delayed facial paralysis are predictive factors for subsequent recovery.
- Published
- 1996
23. The use of the temporoparietal fascial flap in temporal bone reconstruction.
- Author
-
Cheney ML, Megerian CA, Brown MT, McKenna MJ, and Nadol JB
- Subjects
- Adult, Aged, Carcinoma, Adenoid Cystic pathology, Carcinoma, Adenoid Cystic surgery, Ear Neoplasms pathology, Ear Neoplasms surgery, Ear, External pathology, Ear, External surgery, Female, Humans, Male, Middle Aged, Transplantation, Autologous, Fasciotomy, Mastoiditis surgery, Parietal Bone surgery, Surgical Flaps, Temporal Bone surgery
- Abstract
After routine canal wall down mastoidectomy, local muscle flaps with and without bone paté, cartilage and fascia are the standard techniques available to otologists wishing to obliterate the mastoid and reconstruct the external auditory canal. Reconstructive options for temporal bone defects after extirpative surgery for cancer, osteoradionecrosis, and revision surgery for chronic granulomatous otitis media, however, are few. Although the neighboring temporoparietal fascia flap (TPFF), based on the superficial temporal vessels, has been frequently employed for auricular reconstruction, its versatility in temporal bone reconstruction has not been widely explored. The TPFF has recently been employed at our institution in 11 patients who presented with a variety of reconstructive problems, including defects after temporal bone resection, surgery for malignant otitis externa, and revision mastoid surgery. Follow-up in these patients ranged from 1 to 43 months (average 18.4 months) and surgical objectives of achieving a dry mastoid bowl, fully epithelialized canal, and/or reduction of mastoid cavity volume was attained in 100% of cases. The TPFF offers many advantages to the otologic surgeon when faced with reconstruction dilemmas that center around a poorly vascularized mastoid cavity and temporal bone. The TPFF is a reliable source of local well-vascularized tissue that is extremely pliable and facilitates both hearing and nonhearing preservation temporal bone reconstruction.
- Published
- 1996
24. Teflon granuloma presenting as an enlarging, gadolinium enhancing, posterior fossa mass with progressive hearing loss following microvascular decompression.
- Author
-
Megerian CA, Busaba NY, McKenna MJ, and Ojemann RG
- Subjects
- Aged, Diagnosis, Differential, Facial Nerve blood supply, Facial Nerve surgery, Female, Gadolinium, Granuloma, Foreign-Body complications, Granuloma, Foreign-Body etiology, Granuloma, Giant Cell complications, Granuloma, Giant Cell etiology, Hearing Loss, Sensorineural etiology, Humans, Microcirculation surgery, Nerve Compression Syndromes surgery, Spasm surgery, Cranial Fossa, Posterior pathology, Granuloma, Foreign-Body diagnosis, Granuloma, Giant Cell diagnosis, Polytetrafluoroethylene adverse effects, Postoperative Complications etiology
- Abstract
Deleterious effects of Teflon strand placement during microvascular decompression (MVD) for hemifacial spasm are rare. In this report, a patient who had previously undergone suboccipital MVD for hemifacial spasm presented 3 years postoperatively with a progressive asymmetric sensorineural hearing loss and magnetic resonance imaging evidence of an enlarging ipsilateral gadolinium enhancing 1-cm cerebellopontine angle lesion. At surgery a granuloma was found displacing the structures of the internal auditory canal. Histologically, evidence of a Teflon fiber-induced giant cell granuloma was identified. This paper reviews the literature of Teflon-induced histopathology as it relates to posterior fossa MVD surgery, as well as its relation to this previously unreported complication.
- Published
- 1995
25. Fibrous dysplasia of the temporal bone: ten new cases demonstrating the spectrum of otologic sequelae.
- Author
-
Megerian CA, Sofferman RA, McKenna MJ, Eavey RD, and Nadol JB Jr
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Female, Fibrous Dysplasia of Bone diagnosis, Fibrous Dysplasia, Monostotic complications, Fibrous Dysplasia, Monostotic diagnosis, Fibrous Dysplasia, Polyostotic complications, Fibrous Dysplasia, Polyostotic diagnosis, Follow-Up Studies, Hearing Loss, Conductive diagnosis, Hearing Loss, Conductive surgery, Hearing Loss, Sensorineural diagnosis, Hearing Loss, Sensorineural surgery, Humans, Infant, Male, Middle Aged, Cholesteatoma etiology, Ear Diseases etiology, Fibrous Dysplasia of Bone complications, Hearing Loss, Conductive etiology, Hearing Loss, Sensorineural etiology, Temporal Bone
- Abstract
monostotic. Although most patients had a conductive hearing loss, 17% of patients demonstrated profound sensorineural hearing loss ascribable to the lesion, and facial nerve sequelae were noted in nearly 10% of cases. Cholesteatoma complicated almost 40% of cases, usually in the form of a canal cholesteatoma. Ten new cases of temporal bone fibrous dysplasia are described not only to further clarify the spectrum of otologic sequelae but also to help illustrate available treatment options. In addition, this report documents, in three new cases, the previously undescribed progression of conductive hearing loss to profound sensorineural deafness secondary to fibrous dysplasia.
- Published
- 1995
26. Non-paraganglioma jugular foramen lesions masquerading as glomus jugulare tumors.
- Author
-
Megerian CA, McKenna MJ, and Nadol JB Jr
- Subjects
- Adult, Brain ultrastructure, Brain Neoplasms ultrastructure, Cerebral Angiography, Glomus Jugulare Tumor pathology, Hemangiopericytoma ultrastructure, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Plasmacytoma ultrastructure, Tomography, X-Ray Computed, Brain pathology, Brain Neoplasms diagnosis, Brain Neoplasms pathology, Carotid Arteries pathology, Glomus Jugulare Tumor diagnosis, Hemangiopericytoma diagnosis, Hemangiopericytoma pathology, Plasmacytoma diagnosis, Plasmacytoma pathology
- Abstract
Pulsatile tinnitus, hearing loss, lower cranial nerve deficits, and radiographic evidence of a vascular lesion of the jugular foramen have been considered diagnostic of a glomus jugulare tumor. Angiographic evidence of a blood supply from the external carotid artery system, including the ascending pharyngeal artery, further substantiates this diagnosis. This diagnostic algorithm for tumors of the jugular fossa is usually followed by either a surgical exenteration of a presumed glomus jugulare tumor via an infratemporal fossa approach or radiation therapy in selected patients. Pre-treatment biopsy of such lesions is typically not done, nor is it recommended widely in the literature. As demonstrated in this report, a number of lesions, including hemangiopericytoma and extramedullary plasmacytoma presenting in the jugular foramen can mimic glomus jugulare tumors in all aspects of their clinical and radiographic presentation. Omission of a pre-treatment biopsy can lead to a treatment plan appropriate for glomus tumors but suboptimal for these rare pathologic entities. A pre-treatment biopsy of lesions of the jugular foramen by exploratory tympanotomy or postauricular mastoidotomy provides a pathologic diagnosis on which to base treatment of lesions of the jugular foramen, without adding substantial morbidity or decreasing the chances of cure.
- Published
- 1995
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