Kanzaki J, Ogawa K, Ogawa S, Yamamoto M, Ikeda S, O-Uchi T
Department of Otolaryngology, School of Medicine, Keio University, Tokyo, Japan.
Acta Otolaryngol Suppl. 1991;487:125-32. doi: 10.3109/00016489109130457.
Audiological examinations are vital in the diagnosis of acoustic neuroma. In interpreting their results, however, it is necessary to consider the patient's hearing level. The most sensitive audiological examination is auditory brain stem response (ABR) audiometry. Its most useful parameter is the IT5. A U-shaped audiometric configuration suggests AN, since it is seen in 10% of patients with small tumors. Psychological audiometric tests can be excluded from the battery of screening tests since they have low rates of positive diagnosis. The stapedius reflex (SR) test also has a low positive diagnostic rate in cases of small tumors. Even with the parameters of absence of reflex, elevated threshold, and decay combined, the overall SR test has a lower positive diagnostic rate than ABR audiometry. Nevertheless, the SR test can be employed as a screening device in cases in which the hearing level at 2 kHz and lower is 70 dB or lower, even if it is 71 dB or higher at 4 kHz and 8 kHz. At present, ABR audiometry is applicable in only about half of AN cases. Therefore, the need for early diagnosis must be further emphasized.
听力学检查在听神经瘤的诊断中至关重要。然而，在解读其结果时，有必要考虑患者的听力水平。最敏感的听力学检查是听性脑干反应（ABR）测听。其最有用的参数是IT5。U形听力图形态提示听神经瘤，因为在10%的小肿瘤患者中可见。心理测听检查可从筛查检查项目中排除，因为其阳性诊断率较低。镫骨肌反射（SR）检查在小肿瘤病例中的阳性诊断率也较低。即使将无反射、阈值升高和衰减等参数综合起来，总体SR检查的阳性诊断率仍低于ABR测听。尽管如此，在2kHz及以下听力水平为70dB或更低（即使在4kHz和8kHz时为71dB或更高）的情况下，SR检查可用作筛查手段。目前，ABR测听仅适用于约一半的听神经瘤病例。因此，必须进一步强调早期诊断的必要性。
