Ferdinand C. A. Timmer

Vestibular evoked myogenic potentials (VEMP) can detect asymptomatic saccular hydrops.

Objective: The objective of this study was to explore the useful of vestibular evoked myogenic potential (VEMP) testing for detecting endolymphatic hydrops, especially in the second ear of patients with unilateral Ménière disease (MD).

Gamma knife radiosurgery for vestibular schwannomas: Results of hearing preservation in relation to the cochlear radiation dose

This study was designed to evaluate hearing preservation after gamma knife radiosurgery (GKRS) and to determine the relation between hearing preservation and cochlear radiation dose in patients with a sporadic vestibular schwannoma (VS).

Vestibular evoked myogenic potential (VEMP) in patients with Ménière's disease with drop attacks.

Objective: In this retrospective study, we tested the hypothesis that vestibular evoked myogenic potential (VEMP) thresholds are more often elevated or absent in patients with Ménières disease experiencing Tumarkin drop attacks than in other patients with Ménières disease.

Follow-up after gamma knife radiosurgery for vestibular schwannomas: volumetric and axial control rates

A prospective long‐term follow‐up study was conducted to evaluate the results of gamma knife radiosurgery (GKRS) for vestibular schwannoma (VS) patients. Both axial and volumetric measurements are used to determine tumor size during follow‐up.

Predictors of future growth of sporadic vestibular schwannomas obtained by history and radiologic assessment of the tumor

Management of a sporadic vestibular schwannoma (VS) is still a subject of controversy, mainly due to distinct and unpredictable growth patterns. To embark on an appropriate therapy it is necessary to dispose of a reliable prediction about tumor progression. This study aims to design a risk profile with predictors for VS growth. A total of 234 VS patients who were managed conservatively were included. Data concerning (duration of) symptoms and localization of VS were analyzed with Cox proportional hazards regression models. Predictors for growth are unsteadiness/vertigo, no sudden onset of hearing loss and short duration of hearing loss. High-risk patients have (1) VS with an extrameatal localization, short duration of hearing loss and at least one of the two other predictors (unsteadiness/vertigo or no sudden sensorineural hearing loss) or (2) VS with an intrameatal localization and all three other predictors. Low-risk patients have (1) VS with an extrameatal component and no other predictor or (2) VS with an intrameatal localization and at most one other predictor. High-risk patients have a risk of growth of 36.9% in the first year and 64.6% in the second year. For patients with a low risk this is 2.5 and 12.7%, respectively. Simple data gathered at the moment of diagnosis may provide useful information since they may lead to a risk profile for growth.

Endolymphatic sac tumors: clinical outcome and management in a series of 9 cases.

Objectives: Endolymphatic sac tumors (ELSTs) are rare adenomatous tumors arising in the petrous bone, either spontaneously (isolated) or in association with von Hippel-Lindau (VHL) disease. For 9 patients, this study describes the typical features and management of ELST and the clinical outcome of treatment. Similarities and differences are identified for ELST in isolation and in association with VHL disease. Study Design: Case series. Setting: Tertiary referral center. Patients: The patient database was searched for patients diagnosed with ELST. All other tertiary referral centers in The Netherlands were invited to do likewise. Interventions: The patient records were screened for presenting symptoms, hearing, imaging, treatment, and treatment outcome. Histopathologic finding was reviewed by a senior pathologist. Results: Six patients with an isolated ELST and 3 patients with an ELST in association with VHL disease were identified. In the isolated ELST group, 5 patients were treated surgically and 1 patient was administered primary radiotherapy. In the VHL group, 1 patient underwent surgery and 2 patients were treated conservatively after a wait-and-magnetic resonance imaging-scan protocol. All individual treatment outcomes are scrupulously presented in this article. Conclusion: This study compiles and describes 9 cases of ELST. In 8 of 9 patients, the ELST could be controlled by surgery, radiotherapy, or a wait-and-scan protocol. The large interpatient differences make it difficult to standardize the management of this disease. The management is strongly influenced by comorbidity and tumor stage.

Gamma knife radiosurgery for vestibular schwannomas: Identification of predictors for continued tumor growth and the influence of documented tumor growth preceding radiation treatment†

Gamma knife radiosurgery (GKRS) has become an important treatment modality for vestibular schwannomas. The primary aim of this study was to investigate whether tumor growth at the moment of GKRS has any correlation with the outcome. The secondary aim was to identify clinical predictors of radioresistance in vestibular schwannoma patients treated with GKRS.

Prediction of vestibular schwannoma growth: a novel rule based on clinical symptomatology.

Objectives: The aim of this study was to formulate a predictive rule for vestibular schwannoma growth during the initial observation period after diagnosis. Methods: Logistic regression models were fitted, with tumor growth in the first year as the dependent variable and patient characteristics as the independent variables. Backward selection was used to eliminate superfluous predictors. The area under the receiver operating characteristic curve was taken as a measure of the models discriminative power. Results: Eventually, the model or rule consisted of 4 significant growth predictors: Localization (if extrameatal, +1; if intrameatal, 0), sudden sensorineural hearing loss (if present, −1; if absent, 0), balance symptoms (if present, +1; if absent, 0), and complaints of hearing loss for less than 2 years (if present, +1; if absent, or present for more than 2 years, 0). A higher score indicates a higher likelihood of tumor growth during the period of observation after diagnosis. If the total score is 0 or less, the likelihood of tumor growth during the first year after diagnosis is less than 10%. If the score is 3, the likelihood of growth during the first year after diagnosis is more than 70%. Conclusions: We were able to create a useful rule to predict vestibular schwannoma growth during the first year after diagnosis.