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Vestibular evoked myogenic potential (VEMP) in response to a loud air conducted sound (ACS) recorded from extraocular muscles, the so-called ocular VEMP (oVEMP), has been confirmed to be able to evaluate utricular function. This study aimed to evaluate the effect of sleep deprivation (SD) on oVEMP parameters. oVEMPs were recorded in 20 male healthy subjects once after an ordinary sleep and once after 26–29 h of SD. The latencies of peak N1 and P1, N1-P1 amplitude, N1-P1 interval, and asymmetry ratio (AR) of oVEMP recorded from both eyes under normal sleep and SD conditions were 10.04 ± 0.59 ms versus 10.56 ± 0.69 ms (left eye), 14.95 ± 0.92 ms versus 15.64 ± 1.05 ms (left eye), and 7.44 ± 2.86 µV versus 5.26 ± 2.15 µV (left eye); 10.08 ± 0.66 ms versus 10.64 ± 0.73 ms (right eye), 14.88 ± 0.89 ms versus 15.59 ± 1.02 ms (right eye), and 7.16 ± 2.88 µV versus 5.04 ± 2.05 µV(right eye); 10.40 ± 5.81% versus 11.43 ± 6.37%, respectively. After SD, the latencies of oVEMP were delayed and N1-P1 amplitude was lower, whereas N1-P1 interval and AR remained unchanged. The present study showed that oVEMP test could be used to evaluate the fatigue induced by SD.

Spatial disorientation in airplane pilots is a leading factor in many fatal flying accidents. Spatial orientation is the product of integrative inputs from the proprioceptive, vestibular, and visual systems. One condition that can lead to sudden pilot incapacitation in fight is vestibular neuritis. Vestibular neuritis is commonly diagnosed by a finding of unilateral vestibular failure, such as a loss of caloric response. However, because caloric response testing reflects the function of only the superior part of the vestibular nerve, it cannot detect cases of neuritis in only the inferior part of the nerve. We describe the case of a Chinese naval command fighter pilot who exhibited symptoms suggestive of vestibular neuritis but whose caloric response test results were normal. Further testing showed a unilateral loss of vestibular evoked myogenic potentials (VEMPs). We believe that this pilot had pure inferior nerve vestibular neuritis. VEMP testing plays a major role in the diagnosis of inferior nerve vestibular neuritis in pilots. We also discuss this issue in terms of aeromedical concerns.

Benign paroxysmal positional vertigo (BPPV) is the most common disorder of the peripheral vestibular system, characterized by intense, positional provoked vertigo. BPPV is thought to occur due to canalithiasis of the posterior semicircular canal. Recently, a new entity of BPPV, known as horizontal canal (HC)-BPPV, has been recognized. Although only 3 to 8% of BPPV is due to horizontal canal involvement, HC-BPPV is not rare. We present a case of a naval fi ghter pilot who had an incident of HC-BPPV on the ground. The pilot aeromedical evaluation and considerations are discussed.

We were pleased to read the review presented by Eleftheriadou et al. [1], which has been published in Eur Arch Otorhinolaryngol 268(3):331–339, 2011. This review is an excellent practice guide to understand vestibular evoked myogenic potentials. However, I would like to point out two errors in this review. The first error is in the section ‘‘Effect of electrode location on the SCM muscle and responses from the other muscles’’ paragraph 2 line 3, ‘‘...smaller myogenic response (n11–n15) can be recorded over...’’, in which ‘‘n11–n15’’ should be modified as ‘‘p11–n15’’ according to Deriu et al. [2]. The second error is in the section ‘‘Ocular VEMP’’ paragraph 4 line 8, ‘‘...is predominantly determined by saccular activation.’’, in which ‘‘saccular’’ should be modified as ‘‘utricular’’. In my opinion, these typographical errors should be corrected since these errors may baffle and misguide the general reader.

We were pleased to read the report presented by Manzari et al. [1], which has been published in Eur Arch Otorhinolaryngol, 2010, 267(9):1487–1489. They described an unusual patient with reduced inferior vestibular nerve function who provides the complementary but converse evidence for these suggestions by showing reduced cVEMP potentials but normal oVEMPs for both ACS and BCV stimuli, this case report provides further evidence that the origin of oVEMP in response to ACS is the utricle macula [2]. However, I would like to point to one error in Figure 1. In Figure 1 illustration, the authors described ‘‘The strong asymmetry amplitude of the p13–n23 complex between left (normal side) and right (affected side) in cVEMPs is evident (a).’’ The authors confused the direction of the pathology since the patient were diagnosed as having left inferior vestibular neuritis. So the right description is ‘‘The strong asymmetry amplitude of the p13–n23 complex between right (normal side) and left (affected side) in cVEMPs is evident (a).’’ This rectification is important since the description in Figure 1 illustration may baffle the readers.