Enck P, von Giesen H J, Schäfer A, Heyer T, Gantke B, Flesch S, Arendt G, Schmitz N, Frieling T
Department of Gastroenterology, Heinrich Heine University Medical School, Düsseldorf, Germany.
Am J Gastroenterol. 1996 Dec;91(12):2539-43.
A comparison of anal sonography with conventional electromyographic mapping in the evaluation of anal sphincter defects was the aim of this study.
In 23 patients with defecatory problems referred for conventional needle electromyography (EMG), anal endosonography, with a 7.5-MHz, 355 degrees scanner, was performed before EMG to determine the structural integrity of the external anal sphincter. If lesions were found, they were described in terms of location and extent. Subsequently, concentric needle EMG of the external sphincter was performed circumferentially to locate muscle parts exhibiting normal and diminished or missing muscle activity. Lesions found by EMG were also described like those found by sonography.
Of 23 patients, eight exhibited no abnormalities on EMG, and no muscle defects were identified endosonographically in any of these patients. In the remaining 15 patients, EMG showed either an incomplete pattern of interference or a complete absence of voluntary activity; in all of these patients endosonography also identified structural deficit. In 14 of these 15 patients, abnormalities were found at the same location with both endosonography and EMG. In the remaining patient, the two techniques identified structural and functional abnormalities at different locations.
Although EMG is the gold standard for assessment of the functional relevance of muscle defects, anal endosonography yields a sensitivity and specificity of almost 100%.
本研究旨在比较肛门超声检查与传统肌电图测绘在评估肛门括约肌缺陷中的应用。
对23例因排便问题而接受传统针极肌电图（EMG）检查的患者，在进行EMG检查前，使用7.5MHz、355度扫描探头进行肛门腔内超声检查，以确定肛门外括约肌的结构完整性。若发现病变，则描述其位置和范围。随后，对肛门外括约肌进行环形针极肌电图检查，以确定肌肉活动正常、减弱或缺失的部位。肌电图发现的病变也按照超声检查发现的病变那样进行描述。
23例患者中，8例肌电图检查无异常，且这些患者的超声检查均未发现肌肉缺陷。其余15例患者中，肌电图显示干扰型不完全或完全无自主活动；所有这些患者的超声检查也发现了结构缺陷。在这15例患者中的14例，超声检查和肌电图在同一位置发现了异常。在其余1例患者中，两种检查在不同位置发现了结构和功能异常。
虽然肌电图是评估肌肉缺陷功能相关性的金标准，但肛门腔内超声检查的敏感性和特异性几乎达100%。
