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Background: In evoked potential testing, it is common practice to abrade the skin surface as a means of reducing and balancing electrode impedance. The effects of skin preparation and electrode impedance on ocular vestibular-evoked myogenic potential (oVEMP) prevalence and amplitudes are not known., Purpose: We sought to determine whether comparable oVEMP waveforms could be recorded without excessive skin preparation., Research Design: This was a prospective study with a repeated-measures (within-subjects) design., Study Sample: The study group comprised 20 healthy participants (12 females and 8 males) ages 21-57 yr., Data Collection and Analysis: oVEMP reflexes were recorded in response to air-conducted and bone-conducted (AC and BC) stimuli in three conditions. In the first condition (no skin preparation), electrodes were simply placed over the skin surface. For the second condition (moderate skin preparation), oVEMP testing was repeated after the skin had been prepared with 70% isopropyl alcohol swabs. oVEMPs recorded in these two conditions were then compared with those recorded using a third conventional protocol whereby the skin was abraded with skin preparation gel until electrode impedances were low and balanced. For BC stimuli, reflex amplitudes and latencies were compared using a repeated-measures general linear model. For AC stimuli, rates of reflex detection were analyzed using a generalized estimating equation. Nonparametric Friedman tests were used to compare AC oVEMP amplitudes across the three conditions., Results: There was no significant effect of electrode impedance on reflex amplitudes, latencies, or rates of detection (p > 0.05). The results indicated significant stimulus-related artifact (≥3 μV) in 25 of 40 recordings under the high-impedance condition in response to BC stimulation. The stimulus artifact was detectable in 12 of 40 recordings after moderate skin preparation and in 5 recordings after skin abrasion., Conclusions: Comparable rates of reflex detection and oVEMP amplitudes were recorded in the three conditions, implying that rigorous rubbing of the facial skin is largely unnecessary in clinical oVEMP testing. However, for oVEMPs recorded in response to a single-polarity stimulus, reducing and balancing electrode impedances with either isopropyl alcohol wipes or skin abrasion may help reduce unwanted stimulus artifact., (American Academy of Audiology.)

The study compared the effects of Acceptance and Commitment Therapy (ACT) with Tinnitus Retraining Therapy (TRT) on tinnitus impact in a randomised controlled trial. Sixty-four normal hearing subjects with tinnitus were randomised to one of the active treatments or a wait-list control (WLC). The ACT treatment consisted of 10 weekly 60 min sessions. The TRT treatment consisted of one 150 min session, one 30 min follow-up and continued daily use of wearable sound generators for a recommended period of at least 8h/day for 18 months. Assessments were made at baseline, 10 weeks, 6 months and 18 months. At 10 weeks, results showed a superior effect of ACT in comparison with the WLC regarding tinnitus impact (Cohen's d=1.04), problems with sleep and anxiety. The results were mediated by tinnitus acceptance. A comparison between the active treatments, including all assessment points, revealed significant differences in favour of ACT regarding tinnitus impact (Cohen's d=0.75) and problems with sleep. At 6 months, reliable improvement on the main outcome measure was found for 54.5% in the ACT condition and 20% in the TRT condition. The results suggest that ACT can reduce tinnitus distress and impact in a group of normal hearing tinnitus patients., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Does it matter in what order the four irrigations are conducted in the caloric test? It has been suggested that warm water (44 degrees C) elicits stronger reactions than does cold water (30 degrees C), which might be explained simply by slight differences in water temperatures. However, if it can be shown that starting with cold water diminishes the difference between the warm and cold irrigations, it might be worthwhile to apply the cold irrigations first. Binaural, bithermal caloric irrigation was conducted in darkness using electrooculography. Maximum slow-phase velocity was measured. One hundred and eighteen consecutive patients from our laboratory were tested with warm water first and then with cold irrigations. In a second run, 108 subjects were irrigated with cold water before the warm. Employing cold irrigations first produces a smaller difference between the warm and the cold irrigations than does the opposite order. However, the lateral and directional preponderances, according to the formulas of Jongkees, are not affected by this change of irrigation order. The fact that initial warm-water irrigations cause the temperature effect differences to be larger than do initial cold-water irrigations is a phenomenon having only marginal clinical implications.