Faculty of Medicine, Dalhousie University, Halifax, NS, Canada.
Department of Surgery, Division of Otolaryngology - Head and Neck Surgery, Dalhousie University, Faculty of Medicine, Halifax, NS, Canada.
J Otolaryngol Head Neck Surg. 2018 Jul 3;47(1):43. doi: 10.1186/s40463-018-0290-y.
The accurate diagnosis of Eustachian tube (ET) dysfunction can be very difficult. Our aim is to determine whether a 678 Hz probe tone is a more accurate indicator of Patulous ET (PET) than the 226 Hz probe tone when used in compliance over time (COT) testing.
Twenty subjects (11 normal ET ears and 7 PET ears) were individually seated in an examination room and connected to a GSI TympStar Middle Ear Analyzer. The order of probe tone frequency (678 or 226 Hz) was randomized. Baseline "testing" COT recordings for each ear undergoing testing were completed. Subjects were instructed to occlude their contralateral nostril and to breathe forcefully in and out through their ipsilateral nostril until the test had run to completion. This process was repeated with the probe tone that had not been previously run. For the control group, each subject had one random ear tested. For the experimental group, only the affected ear(s) was tested. Wilcoxon rank rum tests were performed to determine statistical significance.
The baseline COT measurements for the control group and PET group were similar, 0.86 mL (SD = 0.34) and 0.74 (SD = 0.33) respectively. Comparing the 226 Hz tone between groups revealed that PET patients had a median COT difference 0.19 mL higher than healthy ET patients, and for the 678 Hz tone, PET patients had a median COT difference of 0.57 mL higher than healthy ET patients. Both were deemed to be statistically significant (p = 0.002, p = 0.004 respectively). The was a statistically significant median COT difference between the 678 Hz and 226 Hz of 0.61 mL (p = 0.034) for the PET group, while the same comparison for the control group of 0.05 mL was not significant (p = 0.262), suggesting that the 678 Hz tone yields a larger response for PET than the 226 Hz tone, and no difference for the control group, thus making it less prone to artifact noise interference.
The 678 Hz probe tone is a more reliable indicator of ET patency, and should be preferably used over the 226 Hz tone for future COT testing.
准确诊断咽鼓管(ET)功能障碍可能非常困难。我们的目的是确定在顺应性随时间变化(COT)测试中,678 Hz 探测音是否比 226 Hz 探测音更能准确指示张咽鼓管(PET)。
20 名受试者(11 名正常 ET 耳和 7 名 PET 耳)分别坐在检查室中,并连接到 GSI TympStar 中耳分析仪。探测音频率(678 或 226 Hz)的顺序是随机的。对接受测试的每只耳朵进行基线“测试”COT 记录。指导受试者用对侧鼻孔闭塞,并通过同侧鼻孔用力呼吸,直到测试完成。用之前未进行过的探测音重复此过程。对于对照组,每位受试者随机测试一只耳朵。对于实验组,仅测试受影响的耳朵。采用 Wilcoxon 秩和检验确定统计学意义。
对照组和 PET 组的基线 COT 测量值相似,分别为 0.86 mL(SD=0.34)和 0.74(SD=0.33)。比较两组之间的 226 Hz 音,发现 PET 患者的 COT 差值中位数比健康 ET 患者高 0.19 mL,而对于 678 Hz 音,PET 患者的 COT 差值中位数比健康 ET 患者高 0.57 mL。两者均具有统计学意义(p=0.002,p=0.004)。PET 组的 678 Hz 与 226 Hz 之间的 COT 差值中位数为 0.61 mL,具有统计学意义(p=0.034),而对照组的同一比较结果为 0.05 mL,无统计学意义(p=0.262),这表明 678 Hz 音对 PET 的反应大于 226 Hz 音,而对照组则没有差异,因此不易受到伪噪声干扰。
678 Hz 探测音是咽鼓管通畅性的更可靠指标,应优先用于未来的 COT 测试,而不是 226 Hz 探测音。