Vernon J A, Meikle M B
Ciba Found Symp. 1981;85:239-62. doi: 10.1002/9780470720677.ch14.
With care to provide properly chosen masking sounds, masking can help in 60-80% of clinically significant tinnitus cases. There is no universal masker; instead, an individual evaluation of each patient's tinnitus must be performed in order to match the masking sounds to the patient's audiogram and the spectral characteristics of the tinnitus. Successful long-term masking can usually be achieved in patients for whom (1) hearing impairment is not excessive. (2) the tinnitus frequency, FT, can be reliably located, and (3) the tinnitus can be completely masked by a band of noise at or near FT at a low sensation level. Such patients often experience residual inhibition (temporary suppression of tinnitus upon cessation of masking) which may accumulate with sustained use of masking, in some cases becoming permanent. Long-term masking is difficult or impossible for patients whose hearing is so impaired they cannot hear the masker, or those for whom the masking sounds must be presented at unacceptably loud levels to obtain adequate coverage of the tinnitus. There is a great need for additional work to determine what factors influence the effectiveness of masking, in order to improve our ability to provide appropriate masking stimuli even for the difficult cases.
谨慎地提供恰当选择的掩蔽声，掩蔽可帮助60%至80%临床上有显著意义的耳鸣病例。不存在通用的掩蔽器；相反，必须对每位患者的耳鸣进行个体评估，以便使掩蔽声与患者的听力图以及耳鸣的频谱特征相匹配。对于以下患者通常可实现成功的长期掩蔽：（1）听力损害不过度；（2）耳鸣频率FT能够可靠地定位；（3）在低感觉水平下，耳鸣能够被FT处或其附近的一段噪声完全掩蔽。这类患者常常会经历残余抑制（掩蔽停止后耳鸣的暂时抑制），持续使用掩蔽可能会使这种抑制累积，在某些情况下会变为永久性抑制。对于听力受损严重以至于听不到掩蔽器的患者，或者对于那些必须以无法接受的高声级呈现掩蔽声才能充分覆盖耳鸣的患者，长期掩蔽是困难的或不可能的。非常需要开展更多工作来确定哪些因素会影响掩蔽的效果，以便提高我们为即使是困难病例提供恰当掩蔽刺激的能力。
