優化cVEMP檢測：2000 Hz短純音提升上半規管裂的診斷準確性

Toward Optimizing cVEMP: 2,000-Hz ToneBursts Improve the Detection of Superior Canal Dehiscence.

優化cVEMP檢測：2000 Hz短純音提升上半規管裂的診斷準確性

Noij KS1,?Herrmann BS2,3,?Guinan JJ Jr2,4,?Rauch SD5,6.

Audiol Neurootol. 2019 Jan 24;23(6):335-344.

背景

The cervical?vestibular?evokedmyogenic potential (cVEMP) test measures saccular and inferior?vestibular?nervefunction. The cVEMP can be elicited with different frequency stimuli andinterpreted using a variety of metrics. Patients with superior semicircularcanal dehiscence (SCD) syndrome generally have lower cVEMP thresholds andlarger amplitudes, although there is overlap with healthy subjects. The aim ofthis study was to evaluate which metric and frequency best differentiatehealthy ears from SCD ears using cVEMP.

頸前庭誘發肌源性電位（cVEMP）測試檢測橢圓囊和下前庭下神經功能。cVEMP可以用不同的頻率刺激引發并使用各種參數指標來解讀。具有上半規管裂（SCD）綜合征的患者通常具有較低的cVEMP閾值和較大的振幅，盡管與健康受試者存在重疊。本研究的目的是評估使用哪種刺激頻率cVEMP能最好地區分健康的耳和SCD耳。

方法：

Twenty-one patients with SCD and 23age-matched controls were prospectively included and underwent cVEMP testing at500, 750, 1,000 and 2,000 Hz. Sound level functions were obtained at allfrequencies to acquire threshold and to calculate normalized peak-to-peakamplitude (VEMPn) and VEMP inhibition depth (VEMPid). Third window indicator(TWI) metrics were calculated by subtracting the 250-Hz air-bone gap from theipsilateral cVEMP threshold at each frequency. Ears of SCD patients weredivided into three groups based on CT imaging: dehiscent, thin or unaffected.The ears of healthy age-matched control subjects constituted a fourth group.

納入21名SCD患者和23名年齡匹配的對照組進行前瞻性研究，并在500,750,1,000和2,000 Hz進行cVEMP測試。在所有頻率下獲得閾值并標準化峰 - 峰振幅（VEMPn）和VEMP抑制深度（VEMPid）。第三窗指標（TWI）為通過從每個頻率的同側cVEMP閾值減去250Hz的氣骨差來計算。根據CT成像將SCD患者分為三組：裂開的，薄的或未受影響。健康年齡匹配的對照受試者構成第四組。

結果：

Comparing metrics at all frequenciesrevealed that 2,000-Hz stimuli were most effective in differentiating SCD fromnormal ears. ROC analysis indicated that for both 2,000-Hz cVEMP threshold and for2,000-Hz TWI, 100% specificity could be achieved with a sensitivity of 92.0%.With 2,000-Hz VEMPn and VEMPid at the highest sound level, 100% specificitycould be achieved with a sensitivity of 96.0%.

比較所有頻率的指標顯示，2,000-Hz刺激在區分SCD和正常耳方面最有效。ROC分析表明，對于2000-Hz cVEMP閾值和2000-Hz TWI，可以實現100％的特異性，靈敏度為92.0％。使用最高聲級的2,000 Hz VEMPn和VEMPid，可以實現100％的特異性，靈敏度為96.0％

結論：

The best diagnostic accuracy of cVEMP inSCD patients can be achieved with 2,000-Hz tone burst stimuli, regardless ofwhich metric is used.

無論使用哪種衡量標準，使用2000-Hz短純音刺激都可以實現cVEMP在SCD患者中的最佳診斷準確性。