Kemaloğlu Y K, Beder L, Sener T, Göksu N
Gazi University Faculty of Medicine Department of ENT-HNS, Yalim sokak 2/13 Küçükesat, 06660 Ankara, Turkey.
Int J Pediatr Otorhinolaryngol. 2000 Sep 15;55(1):21-7. doi: 10.1016/s0165-5876(00)00367-0.
Purpose of this study was to find out test accuracy and predictivity of tympanometry (TYMP) and parameters (reflectivity and curve angle) of acoustic reflectometry (AR) in the ears with prior clinic and otoscopic evidences of effusion in which no effusion was detected by myringotomy, by comparing with the data found in normal ears and in those with effusion.
While study group included 31 ears with chronic retraction in which no effusion was detected by myringotomy, control group included 150 fully normal ears and 150 ears with effusion confirmed by myringotomy. B tracings in TYMP, and values of reflectivity higher than 5 and curve angle lower than 75 degrees in AR were accepted as indicators of effusion; in the combined test, the ears with non-B tracings in which curve angle higher than 75 degrees were accepted as those without effusion.
False positivity values of TYMP, reflectivity and curve angle and the combined test found in the ears with chronic retraction without effusion (29, 23, 19 and 35% respectively; chi(2)-test, P > 0.1) were significantly higher than normal ears (chi(2)-test, P < 0.001), but lowe than those of effusion (chi(2)-test, P<0.0001). Further, although negative predictivity values of TYMP, reflectivity and curve angle were found to be lower in these ear, compared to normal ears (chi(2)-test, P < 0.01), the combined test reached to a perfect negative predictivity, as much as in normal ears. On the other hand, positive predictivity values were decreased in the ears with chronic retraction without effusion by only reflectivity.
By both TYMP and AR alone, it is more difficult to find out the ears without effusion among the ears clinically and otoscopically diagnosed as otitis media than to find out normal ears. Therefore, in clinical work, false positivity of these devices were higher, and their specificity and negative predictivity were lower; although the combined test solved problem of low negative predictivity, high number of false positive ears in clinical work, that is lower specificity, continues to be an unsolved problem by either TYMP or AR alone, or both together.
本研究的目的是通过与正常耳和有积液耳的数据进行比较，找出鼓室导抗图（TYMP）以及声反射测量法（AR）的参数（反射率和曲线角度）在临床上和耳镜检查有积液迹象但鼓膜切开术未发现积液的耳朵中的测试准确性和预测性。
研究组包括31只鼓膜慢性内陷且鼓膜切开术未发现积液的耳朵，对照组包括150只完全正常的耳朵和150只经鼓膜切开术证实有积液的耳朵。鼓室导抗图中的B型曲线，以及声反射测量法中反射率高于5且曲线角度低于75度的值被视为积液的指标；在联合测试中，曲线角度高于75度且非B型曲线的耳朵被视为无积液。
在鼓膜慢性内陷但无积液的耳朵中，鼓室导抗图、反射率和曲线角度以及联合测试的假阳性值（分别为29%、23%、19%和35%；卡方检验，P>0.1）显著高于正常耳朵（卡方检验，P<0.001），但低于有积液的耳朵（卡方检验，P<0.0001）。此外，虽然这些耳朵中鼓室导抗图、反射率和曲线角度的阴性预测值与正常耳朵相比有所降低（卡方检验，P<0.01），但联合测试达到了与正常耳朵一样完美的阴性预测性。另一方面，仅反射率使鼓膜慢性内陷但无积液的耳朵的阳性预测值降低。
单独使用鼓室导抗图和声反射测量法，在临床和耳镜诊断为中耳炎的耳朵中找出无积液的耳朵比找出正常耳朵更困难。因此，在临床工作中，这些设备的假阳性率较高，其特异性和阴性预测性较低；虽然联合测试解决了阴性预测性低的问题，但临床工作中假阳性耳朵数量较多（即特异性较低），仍然是单独使用鼓室导抗图或声反射测量法，或两者一起使用都未解决的问题。
