Hyperventilation-induced nystagmus in vestibular schwannoma and unilateral sensorineural hearing loss

Abstract

We evaluated the incidence and characteristics of hyperventilation-induced nystagmus (HVN) in 49 patients with gadolinium-enhanced magnetic resonance imaging evidence of vestibular schwannoma and 53 patients with idiopathic unilateral sensorineural hearing loss and normal radiological findings. The sensitivity and specificity of the hyperventilation test were compared with other audio-vestibular diagnostic tests (bedside examination of eye movements, caloric test, auditory brainstem responses) in the two groups of patients. The hyperventilation test scored the highest diagnostic efficiency (sensitivity 65.3 %; specificity 98.1 %) of the four tests in the differential diagnosis of vestibular schwannoma and idiopathic unilateral sensorineural hearing loss. Small tumors with a normal caloric response or caloric paresis were associated with ipsilateral HVN and larger tumors and severe caloric deficits with contralateral HVN. These results confirm that the hyperventilation test is a useful diagnostic test for predicting vestibular schwannoma in patients with unilateral sensorineural hearing loss.

The diagnostic accuracy of non‐imaging screening protocols for vestibular schwannoma in patients with asymmetrical hearing loss and/or unilateral audiovestibular dysfunction: a diagnostic review and meta‐analysis

“…Studies providing information on sex included 806 (50.7%) men and 784 (49.3%) women. [13][14][15][16][17] The mean age reported varied from 45 to 57 years. [13][14][15][16][17] The incidence of VS ranged from 1.4% to 39.6% in the included cohort studies.…”

“…[13][14][15][16][17] The mean age reported varied from 45 to 57 years. [13][14][15][16][17] The incidence of VS ranged from 1.4% to 39.6% in the included cohort studies. 13,[16][17][18][19][20] Most other studies were case-control studies.…”

“…Several authors studied multiple screening protocols in their study population. 14,15,17,18,21,22 Six studies used PTA as index test, comprising 3116 patients. 14,[17][18][19]21,22 Five of these 14,17,18,21,22 tested specific PTA protocols (hearing thresholds at different frequencies) that had been published before in 2616 patients, and two 14,19 tested different PTA shapes (description of the PTA shape without providing specific thresholds, e.g.…”

“…ABR was tested in five studies in a total of 652 patients. 13,15,16,22,23 Hyperventilation test, electronystagmography, caloric irrigation, presenting symptoms and a prediction model were tested in one study each, comprising 102, 100, 102, 881 and 420 patients, respectively. 15,20,22,24 Quality assessment…”

“…Table 4 provides an overview of the results. 13,15,16,22,23 The sensitivity of different combinations of presenting symptoms varied, with the highest sensitivity of 58% [95% CI: 28-85] for symptoms of hearing loss. Reported specificities were higher, ranging from 63% [95% CI: 60-66] for hearing loss only, to 99% [95% CI: 98-100] for the combination of hearing loss, pulsatile tinnitus, dizziness and other symptoms.…”