Dataset Information

Bilaterally Abnormal Head Impulse Tests Indicate a Large Cerebellopontine Angle Tumor.

ABSTRACT:

Background and purpose

Tumors involving the cerebellopontine angle (CPA) pose a diagnostic challenge due to their diverse manifestations. Head impulse tests (HITs) have been used to evaluate vestibular function, but few studies have explored the head impulse gain of the vestibulo-ocular reflex (VOR) in patients with a vestibular schwannoma. This study tested whether the head impulse gain of the VOR is an indicator of the size of a unilateral CPA tumor.

Methods

Twenty-eight patients (21 women; age=64±12 years, mean±SD) with a unilateral CPA tumor underwent a recording of the HITs using a magnetic search coil technique. Patients were classified into non-compressing (T1-T3) and compressing (T4) groups according to the Hannover classification.

Results

Most (23/28, 82%) of the patients showed abnormal HITs for the semicircular canals on the lesion side. The bilateral abnormality in HITs was more common in the compressing group than the non-compressing group (80% vs. 8%, Pearson's chi-square test: p<0.001). The tumor size was inversely correlated with the head impulse gain of the VOR in either direction.

Conclusions

Bilaterally abnormal HITs indicate that a patient has a large unilateral CPA tumor. The abnormal HITs in the contralesional direction may be explained either by adaptation or by compression and resultant dysfunction of the cerebellar and brainstem structures. The serial evaluation of HITs may provide information on tumor growth, and thereby reduce the number of costly brain scans required when following up patients with CPA tumors.

SUBMITTER: Kim HJ

PROVIDER: S-EPMC4712288 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Publications

Bilaterally Abnormal Head Impulse Tests Indicate a Large Cerebellopontine Angle Tumor.

Kim Hyo Jung HJ Park Seong Ho SH Kim Ji Soo JS Koo Ja Won JW Kim Chae Yong CY Kim Young Hoon YH Han Jung Ho JH

Journal of clinical neurology (Seoul, Korea) 20160101 1

<h4>Background and purpose</h4>Tumors involving the cerebellopontine angle (CPA) pose a diagnostic challenge due to their diverse manifestations. Head impulse tests (HITs) have been used to evaluate vestibular function, but few studies have explored the head impulse gain of the vestibulo-ocular reflex (VOR) in patients with a vestibular schwannoma. This study tested whether the head impulse gain of the VOR is an indicator of the size of a unilateral CPA tumor.<h4>Methods</h4>Twenty-eight patient ...[more]

PMID: 26754780

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Dataset Information

Bilaterally Abnormal Head Impulse Tests Indicate a Large Cerebellopontine Angle Tumor.

Background and purpose

Methods

Results

Conclusions

Publications

Bilaterally Abnormal Head Impulse Tests Indicate a Large Cerebellopontine Angle Tumor.

Similar Datasets

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