Vestibular evoked myogenic potentials, auditory brainstem response and caloric test findings in acoustic neuroma

The aim of this study is to study VEMP, ABR and caloric test findings in acoustic neuroma and also to find out if the VEMP could be useful in classifying acoustic neuroma according to the involved nerves. The clinical results of 12 patients [5 males and 7 females] who underwent VEMP, ABR and caloric testing preoperatively and were surgically and hisopathologically confirmed to had acoustic neuroma were reviewed. Ten normal volunteers [5 males and 5 females; age range 22-40 and mean 30.5 years] were also examined. All the subjects enrolled in this study underwent the following: Detailed neurootological history and examination with a comprehensive audiologic evaluation with hearing thresholds, word discrimination, tympanometry and acoustic reflexes, VEMP, ABR, and caloric test were done. The presenting symptoms were progressive SNHL in 5 patients, one had facial palsy in addition, sudden SNHL in 2 patients, unilateral tinnitus in 2 patients and dizziness in 3 patients. Biphasic potentials [P13-N23] were observed on the SCM ipsilateral to the stimulated unaffected side in all 12 patients. When the affected side was stimulated, 8 patients did not show VEMPs. one patient showed decreased responses on the affected side. Three patients show ed normal responses on the affected side and on the unaffected side. Nine patients had decreased caloric responses [canal paresis >20%] on the affected side. Whereas 6 patients had abnormal findings on both VEMP testing and caloric testing, 3 patients showed abnormal findings only on the VEMP, and 3 patients showed abnormal findings only on the caloric test. Tn patients showed abnormal ABR. VEMP testing could still be a useful neuro physiological test for diagnosing acoustic neuroma because VEMP testing and caloric testing could classify acoustic neuromas according to the involved nerves: The inferior vestibular nerve or the superior vestibular nerve.

Migraine related dizziness: findings and management outcome

The purpose of the study is to determine the common findings in migraine-related dizziness and the outcome of management using a combination of diet control, inedical treatment and physical therapy. Forty six patients diagnosed with dizziness attributed to migraine underwent the following: Detailed history taken, basic audiological evaluations, ABR, ENG. ECoG and MRI were done in selected patients. Complete resolution or substantial improvement of the vestibular symptoms attributed to migraine in 46 patients reported in the present study was achieved. In 95% of the patients with episodic vertigo, 91% of the patients with positional vertigo, 80% of the patients with no vertiginous dizziness and 89% of the patients with aural fullness and phonophobia. The diagnosis of migraine-related dizziness relies primarily on history, physical examination, test results of cochlear and vestibular function, imaging and electrophysiological studies. Successful management was achieved using diet control, stress management, sleep improvement, pharmacological therapy and vestibular rehabilitation therapy.