Human vestibular schwannoma reduces density of auditory nerve fibers in the osseous spiral lamina.

Hearing loss in patients with vestibular schwannoma (VS) is commonly attributed to mechanical compression of the auditory nerve, though recent studies suggest that this retrocochlear pathology may be augmented by cochlear damage. Although VS-associated loss of inner hair cells, outer hair cells, and spiral ganglion cells has been reported, it is unclear to what extent auditory-nerve peripheral axons are damaged in VS patients. Understanding the degree of damage VSs cause to auditory nerve fibers (ANFs) is important for accurately modeling clinical outcomes of cochlear implantation, which is a therapeutic option to rehabilitate hearing in VS-affected ears. A retrospective analysis of human temporal-bone histopathology was performed on archival specimens from the Massachusetts Eye and Ear collection. Seven patients met our inclusion criteria based on the presence of sporadic, unilateral, untreated VS. Tangential sections of five cochlear regions were stained with hematoxylin and eosin, and adjacent sections were stained to visualize myelinated ANFs and efferent fibers. Following confocal microscopy, peripheral axons of ANFs within the osseous spiral lamina were quantified manually, where feasible, and with a "pixel counting" method, applicable to all sections. ANF density was substantially reduced on the VS side compared to the unaffected contralateral side. In the upper basal turn, a significant difference between the VS side and unaffected contralateral side was found using both counting methods, corresponding to the region tuned to 2000 Hz. Even spiral ganglion cells (SGCs) contralateral to VS were affected by the tumor as the majority of contralateral SGC counts were below average for age. This observation provides histological insight into the clinical observation that unilateral vestibular schwannomas pose a long-term risk of progression of hearing loss in the contralateral ear as well. Our pixel counting method for ANF quantification in the osseous spiral lamina is applicable to other pathologies involving sensorineural hearing loss. Future research is needed to classify ANFs into morphological categories, accurately predict their electrical properties, and use this knowledge to inform optimal cochlear implant programming strategies.

Assessing the Prognostic Value of the ChOLE Classification in Predicting the Severity of Acquired Cholesteatoma.

OBJECTIVE: To assess the prognostic value of the ChOLE classification in predicting the severity of acquired cholesteatoma. METHOD: A retrospective chart review of patients undergoing primary cholesteatoma surgery in our tertiary referral center. The primary outcome measures were analyzed in three groups of follow up (FU): residual cholesteatoma in group A, FU > 52 weeks after last-look surgery or MRI-DWI; recurrent cholesteatoma in group B, FU > 52 weeks after last outpatient visit; and adverse events (AE) in group C, FU > 12 weeks after surgery. Cholesteatomata were staged according to the ChOLE classification. Kaplan-Meier curves were used to determine the prognostic value of the classification in predicting cholesteatoma severity, while correcting for FU. RESULTS: No significant differences were observed between the various stages of the ChOLE classification and residual or recurrent cholesteatoma rate, nor the occurrence of AE. Cholesteatoma extension to the sinus tympani or widespread in the mastoid, as well as absence of the stapes superstructure were predictive of residual disease. Sclerotic mastoids had a lower risk of residual disease than mastoids with good or poor pneumatization and ventilation. Poorly ventilated and poorly pneumatized mastoids were associated with increased risk of recurrence. Widespread cholesteatoma in the mastoid as well as presence of preoperative extracranial complications were correlated with an increased risk of AE. CONCLUSION: The ChOLE classification does not predict residual nor recurrent disease, nor the occurrence of AE, in our study population. Risk factors for severe cholesteatoma were identified, potentially useful for the development of future classifications.

Identifying epithelial borders in cholesteatoma surgery using narrow band imaging.

PURPOSE: To quantify changes in the perceived epithelial border with narrow band imaging (NBI) and white light imaging (WLI) during cholesteatoma surgery and to objectify possible benefits of NBI in otology. METHODS: Perioperative digital endoscopic images were captured during combined approach tympanoplasty at our tertiary referral center using WLI and NBI (415 nm and 540 nm wavelengths). Sixteen otologic surgeon defined the epithelial borders within 16 identical WLI and NBI photos. Pixels of these selections were calculated to analyze the quantitative difference between WLI and NBI. A questionnaire also analyzed the qualitative differences. RESULTS: Sixteen otologic surgeons participated in the study. Stratified per photo, only two photos yielded a significant difference: less pixels were selected with NBI than WLI. A Bland-Altman plot showed no systemic error. Stratified per otologist, four participants selected significantly more pixels with WLI than with NBI. Overall, no significant difference between selected pixels was found. Sub-analyses of surgeons with more than 5 years of experience yielded no additional findings. Despite these results, 60% believed NBI could be advantageous in defining epithelial borders, of which 83% believed NBI could reduce the risk of residual disease. CONCLUSION: There was no objective difference in the identification of epithelial borders with NBI compared to WLI in cholesteatoma surgery. Therefore, we do not expect the use of NBI to evidently decrease the risk of residual cholesteatoma. However, subjective assessment does suggest a possible benefit of lighting techniques in otology.

Evaluation of Long-term Cholesteatoma Recidivism: Using the JOS, EAONO-JOS, and STAMCO Cholesteatoma Staging Systems.

OBJECTIVE: To assess the prognostic value of the Japanese Otological Society (JOS), EAONO-JOS, and STAMCO classifications in predicting the severity of acquired cholesteatoma and to identify other factors that could influence residual and recurrent cholesteatoma, as well as adverse events (AE). METHOD: A retrospective chart review of patients undergoing primary cholesteatoma surgery in our tertiary referral center. Primary outcome measures were based on three groups of follow-up (FU): Group A, studying residual cholesteatoma, FU > 52 weeks of last-look surgery or magnetic resonance imaging, diffusion-weighted imaging; group B, studying recurrent disease, FU > 52 weeks of last outpatient clinic visit; and group C, studying AE, FU > 12 weeks after surgery. Cholesteatomata were staged according to the JOS, EAONO-JOS, and STAMCO classifications. Kaplan-Meier curves were used to determine the prognostic value of the various classifications and to identify other determining factors, while correcting for FU. RESULTS: FU was found to be a significant confounder. No correlation was found between staging and the occurrence of residual or recurrent disease, nor the occurrence of AE. Type of surgery was a significant determinant of all three primary outcome measures. A higher age was associated with a lower risk of residual disease. CONCLUSION: In our population the JOS, EAONO-JOS, and STAMCO classifications have limited prognostic value. Three main confounders were identified that pose a challenge in developing a universal classification: FU, surgery type, and age. Cholesteatoma staging should be postponed until a system is developed which significantly correlates cholesteatoma stage to cholesteatoma severity, to have implications for management strategies.

Dyssynergic defecation may play an important role in postoperative Hirschsprung's disease patients with severe persistent constipation: analysis of a case series.

BACKGROUND: After surgery for Hirschsprung's disease (HD) the majority of patients have satisfactory clinical outcomes. Nevertheless, a substantial number of patients remain who suffer from severe persistent constipation. Current consensus attributes these complaints to the hallmarks of HD. In non-HD patients a cause for severe constipation is dyssynergic defecation. METHODS: Retrospectively, we reviewed the medical records of ten postoperative HD patients with severe persistent constipation who had undergone extensive anorectal function tests to diagnose the reason for the constipation. We analyzed the results of these tests. RESULTS: During the last three years, ten postoperative HD patients with severe persistent constipation were given extensive anorectal function tests. All ten patients were diagnosed with dyssynergic defecation. The ages at the time of diagnosis ranged from 7 to 19years with a median age of 12years. Signs of an enlarged rectum were seen in all ten patients, with a maximum measured value of 845mL. CONCLUSIONS: Patients with HD may also suffer from dyssynergic defecation. It is important to consider this possibility when dealing with severe persistent constipation in postoperative HD patients. Viable options for treating dyssynergic defecation are available that could prevent irreversible long-term complications.