Cochleovestibular symptoms related to the site of vestibular schwannoma

Changes in pattern of presentation of patients with unilateral vestibular schwannoma over two decades: Influence of cell phone use in early diagnosis

We aimed to study whether the increased use of cell phone in south Asia over the past two decades has impacted presentation of patients with vestibular schwannoma (VS). In this observational cohort study, data on cell phone use and severity of hearing loss and tumor size was collected using a questionnaire through a patient interview (n = 62) in consecutive patients with VS managed between 2017 and 2020. Association between cell phone use and severity of hearing loss and tumor size were studied and compared with our data published earlier when telephone use was not widely prevalent. 71% of the 62 patients (aged between 15 and 81 years) had large or giant VS. Pure tone audiometry showed moderately severe or profound hearing loss in77.4%. Sixty (96.7%) patients used cell phones. 50% of patients complained of difficulty in using their cell phone because of hearing loss. Compared to the earlier era, a higher proportion consulted an ENT surgeon first for hearing loss (59.7% vs 26%; p = 0.0005) and had small or medium sized tumors (29% vs 8%; p = 0.008) with a smaller mean tumor size (3.3 vs 3.9 cm; p = 0.03). Increased cell phone use has led to earlier diagnosis of VS and smaller tumours in recent years when compared to an earlier era. However, the vast majority of patients continue to present with severe to profound hearing loss and large tumors.

Predicting Functional Outcomes and Length of Stay Following Acoustic Neuroma Resection

OBJECTIVES

To examine whether simple mobility assessments can predict functional limitations and length of hospitalization after acoustic neuroma (AN) resection.

STUDY DESIGN

Prospective case series.

METHODS

A prospective clinical study of adult patients undergoing AN resection by either the translabyrinthine, retrosigmoid, or middle fossa approach was conducted at a tertiary center. Preoperative mobility assessments included the functional gait assessment (FGA) and the 10-m walk (10 MW). Postoperatively, the Activity Measure for Post-Acute Care (AMPAC, at 48 hours), FGA, and 10 MW (at 1 week) were obtained. Demographic and medical data were collected.

RESULTS

One hundred and thirty-eight patients were analyzed (mean age: 48.3 years, 68.8% female). Mean length of stay (LOS) was 3.1 days. The translabyrinthine approach was most commonly performed (48.6%). On regression analyses, preoperative FGA (P = 0.03) and 48-hour postoperative AM-PAC (P < 0.001) independently predicted LOS, even after accounting for age, gender, body mass index, and tumor size. On receiver operating characteristic analysis, a preoperative FGA cut score of 25.5 predicted a protracted hospital stay (>4 days) with a sensitivity of 77% and specificity of 50% (area under curve: 68.5).

CONCLUSION

This study demonstrated that preoperative mobility assessments can predict functional limitations and LOS after AN resection. These objective tools can be used by clinicians to manage expectations and guide preoperative counseling in patients considering surgery.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:644-648, 2021.

The Role for Imaging in the Investigation of Isolated Objective Vestibular Weakness

OBJECTIVE

Unilateral vestibular weakness has considerable potential etiologies. One source is a vestibular schwannoma. This article evaluates, in the absence of other symptoms and signs, if unilateral vestibular weakness is an analogue to asymmetric sensorineural hearing loss and serves as an indication for lateral skull base imaging.

STUDY DESIGN

Retrospective chart review.

SETTING

Academic tertiary center.

SUBJECTS AND METHODS

All patients undergoing caloric assessment between January 1, 2012, and June 30, 2018, were investigated. Patients with unilateral vestibular weakness (a left-right difference >25% on electronystagmography) were included in the study. A provincial encompassing image library was surveyed for potential adequate imaging (computed tomography internal auditory canal infused, magnetic resonance imaging [MRI] brain, MRI internal auditory canal) of the target population within the preceding 5 years. Presence/absence of vestibular schwannoma on imaging was determined.

RESULTS

Of the 3531 electronystagmography reports reviewed during the period, 864 patients were identified with unilateral vestibular weakness. Of these, 542 had sufficient imaging, and 14 vestibular schwannomas were identified. Only 1 individual had a vestibular weakness in isolation, while the remaining 13 patients also suffered from documented sensorineural hearing loss that would have mandated MRI scanning.

CONCLUSION

The results of our study suggest that, in isolation, vestibular weakness is an insufficient indicator for lateral skull base imaging.

Long-term dizziness handicap in patients with vestibular schwannoma: a multicenter cross-sectional study

OBJECTIVE

(1) To characterize long-term dizziness following observation, microsurgery, and stereotactic radiosurgery (SRS) for small to medium-sized vestibular schwannoma (VS) using a validated self-assessment inventory; and (2) to identify clinical variables associated with long-term dizziness handicap.

STUDY DESIGN

Cross-sectional observational study.

SETTING

Two independent tertiary academic referral centers: one located in the United States and one in Norway.

SUBJECTS AND METHODS

All patients with sporadic VS of less than 3 cm who underwent primary microsurgery, SRS, or observation between 1998 and 2008 were identified. Subjects were surveyed via a postal questionnaire using the Dizziness Handicap Inventory (DHI) and a VS symptom questionnaire.

RESULTS

The overall survey response rate was 79%. A total of 538 respondents (mean age, 64 years; 56% female) were analyzed, and the mean time interval between treatment and survey was 7.7 years. Pretreatment variables associated with greater dizziness handicap included female sex, older age, larger tumor size, preexisting diagnosis of headache or migraine, and symptoms of dizziness predating treatment. Significant posttreatment features strongly associated with poor long-term DHI scores included frequency and severity of ongoing headache. On multivariable analysis, treatment modality did not influence long-term dizziness handicap.

CONCLUSION

At a mean of approximately 8 years following treatment, over half of patients with VS reported ongoing dizziness. The authors have identified several baseline features that may help predict the risk of lasting dizziness. Treatment modality does not appear to influence long-term DHI score. We found a strong association between posttreatment headache and poor dizziness handicap. Future study is needed to further define this relationship.

Change in tinnitus after treatment of vestibular schwannoma: microsurgery vs. gamma knife radiosurgery

PURPOSE

Tinnitus is a very common symptom of vestibular schwannoma, present in 45 to 80% of patients. We evaluated changes in tinnitus after translabyrinthine microsurgery (TLM) or gamma knife radiosurgery (GKS).

MATERIALS AND METHODS

Among 78 patients with vestibular schwannoma who underwent TLM or GKS at Severance Hospital from 2009-2012, 46 patients with pre- or postoperative tinnitus who agreed to participate were enrolled. Pure tone audiometry, tinnitus handicap inventory (THI), visual analogue scale (VAS) scores for loudness, awareness, and annoyance were measured before and after treatment. Changes of THI and VAS were analysed and compared according to treatment modality, tumour volume, and preoperative residual hearing.

RESULTS

In the TLM group (n=27), vestibulocochlear nerves were definitely cut. There was a higher rate of tinnitus improvement in TLM group (52%) than GKS group (16%, p=0.016). The GKS group had a significantly higher rate of tinnitus worsening (74%) than TLM group (11%, p<0.001). Mean scores of THI and VAS scores significantly decreased in the TLM group in contrast to significant increases in the GKS group. Tumor volume and preoperative hearing did not affect the changes in THI or VAS.

CONCLUSION

GKS can save vestibulocochlear nerve continuity but may damage the cochlea, cochlear nerve and can cause worsening tinnitus. In cases where hearing preservation is not intended, microsurgery with vestibulocochlear neurectomy during tumor removal can sometimes relieve or prevent tinnitus.

Analysis of causes for late presentation of Indian patients with vestibular schwannoma

OBJECTIVE

To determine the causes of delay in diagnosis and treatment of Indian patients with vestibular schwannomas.

METHODS

In a prospective study from 2003 to 2005, 50 patients with a confirmed diagnosis of vestibular schwannoma were interviewed to determine the causes for (1) the delay between the patient noting the initial symptom and the definitive diagnosis, and (2) the reasons for delayed diagnosis.

RESULTS

In 90 per cent of patients, the initial symptom was either hearing loss (62 per cent), vertigo (24 per cent) or tinnitus (4 per cent). However, most patients had been diagnosed and had presented for surgery only after neurological symptoms had became apparent. The delay between the initial medical consultation and the final diagnosis ranged from one month to 204 months (mean +/- standard deviation, 32.2 +/- 38.9 months). After the patient had noted symptoms, the diagnosis of vestibular schwannoma was delayed due to doctor-related causes in 80 per cent of cases, and due to patient-related causes in 20 per cent. Delay following diagnosis was minimal.

CONCLUSIONS

Delay in the diagnosis of vestibular schwannoma in Indian patients is due to both doctor- and patient-related factors.

Pre- and intraoperative predictive factors of facial palsy in vestibular schwannoma surgery

CONCLUSION

S These results support previous ones with regard to FN risk factors in VS surgery. However, they also provide new preoperative factors that influence postoperative FN function, such as clinical symptoms, the nature of the surgical procedure (use of laser) and ABR results.

OBJECTIVE

To determine pre- and perioperative factors influencing facial nerve (FN) outcome in vestibular schwannoma (VS) surgery.

MATERIAL AND METHODS

A total of 424 patients undergoing VS surgery were included in this retrospective study. Patients were divided into two groups according to the existence or absence of a FN palsy during the 8 days following surgery (Groups 1 and 2, respectively). Various parameters were evaluated preoperatively as follows. Quantitative parameters: age; duration of clinical symptoms; pure-tone audiometry (PTA) results; speech reception threshold; speech discrimination score; auditory brainstem response (ABR) results; and transient-evoked otoacoustic emission amplitude. Qualitative parameters: gender; side of the tumor; angle between the tumor and the internal auditory canal (VS/IAC angle) < or = or > 30 degrees; MRI aspect (n = 69); surgical approach; ease of the surgical procedure, the use or non-use of laser dissection; and the histological Antoni's type of the tumor. RESULTS Pre- and perioperative factors that differed significantly between Groups 1 and 2 were as follows. Quantitative factors: tinnitus duration was longer and PTA and ABR results were worse in Group 1. Qualitative factors: heterogenous/cystic MRI aspect, use of retrosisgmoid and middle fossa approaches, easy surgical procedure, dissection without laser and Antoni's type A were more frequently found in Group 1.

[Audiologic diagnostics of vestibular schwannoma]

INTRODUCTION

Vestibular schwannoma (acoustic neuroma) is a rare, but important cause of sensorineural hearing loss. Patients with asymmetric hearing loss, or unilateral tinnitus should be evaluated expeditiously, to prevent further neurological damage.

AUDIOLOGIC DIAGNOSTICS

Audiologic diagnostics represents the basic diagnosis for early detection of vestibular schwannoma. Patients with vestibular schwannomas may present with a variety of clinical features, including retrocochlear pattern of sensorineural hearing loss. Supraliminary audiometry, tympanometry, stapedius reflex and otoacoustic emissions as well as vestibular response to caloric testing are methods for selection of patients with suspicion of this tumor.

CONCLUSION

The golden standard for audiologic diagnostics of vestibular schwannoma is BAEP (Brainstem Auditory Evoked Potentials). Patients with pathological findings of BAEP should undergo MRI of the posterior fossa. Gadolinium-enhanced magnetic resonance imaging is the best and final tool for making a diagnosis of vestibular schwannoma.