Studying VEMP in Sudden Sensorineural Hearing Loss

Abstract

Introduction: Sudden sensorineural hearing loss (SSNHL) has a prevalence of 10 in 100,000. Viral infections, vascular obstruction and rupture of the intracochlear membranes are supposed to be its most common etiologies. About 40% of patients experience vertigo or imbalance. The VEMP (vestibular evoked myogenic potentials) test is a known approach for detailed study of the labyrinth. The advantage of this test in comparison to other tests is the selected study of sacculus and sacculocochlear pathways. Materials and Methods: In this cross sectional study all patients with SSNHL diagnosis were admitted and underwent routine standard treatments and diagnostic tests. Clinical symptoms and paraclinic findings were recorded in especially designed forms and VEMP test was performed on admission. Results: Among the 43 cases with sudden sensorineural hearing loss, 14 (32.6%) had vertigo. Thirteen patients (39.2%) out of 43 had a negative (abnormal) VEMP, 6 of which (42.9%) had vertigo, while in the 30 VEMP positive (normal) cases, vertigo was detected in 8 (26.6%). Discussion: Saccular dysfunction seems to be an important finding in SSNHL. Although it is more prevalent in the patients with vertigo, it can be found in the non-dizzy cases. VEMP disturbance in SSNHL shows more extensive pathological involvement. Conclusion: In SSNHL the pathology isn't limited to the cochlea and even in patients with no vestibular symptoms sacculus might be involved.