Department of Neurology, Medical Faculty of Karadeniz Technical University, 61080 Trabzon, Turkey.
Clin Neurophysiol. 2011 Jul;122(7):1463-9. doi: 10.1016/j.clinph.2010.11.021. Epub 2011 Feb 16.
Diagnosis of carpal tunnel syndrome (CTS) is difficult in patients with diabetic polyneuropathy as both conditions may affect median nerve conduction in a similar manner. There is no agreement about which electrodiagnostic tests are more efficient in determining CTS accurately in these patients. In this study, we aimed to define the best electrodiagnostic test in the diagnosis of CTS in diabetic polyneuropathy patients.
We prospectively investigated 72 patients with CTS (140 hands), 32 patients with diabetic polyneuropathy without CTS (61 hands), 35 patients with diabetic polyneuropathy with CTS (62 hands) and 43 healthy controls (86 hands). Standard nerve conduction studies, segmental and comparative median nerve conduction tests were performed in all subjects. Cut-off values, sensitivities and specificities of each test for the diagnosis of CTS in diabetic polyneuropathy patients were determined by using receiver operating characteristic (ROC) curve.
Distoproximal latency ratio (DPLR) with a sensitivity of 90% and specificity of 81% for the cut-off value of 1 and median and ulnar sensory latency difference to digit 4 (MUDD4) with a sensitivity of 90% and specificity of 85% for the cut-off value of 0.35 showed the highest sensitivity and specificity in the diagnosis of CTS in diabetic polyneuropathy patients among all nerve conduction tests. Wrist-palm median sensory conduction velocity (W-P SCV) and median and radial sensory latency difference to digit 1 (MRDD1) also showed high sensitivity and specificity.
Segmental median nerve conduction studies like DPLR and W-P SCV and sensory comparative tests such as MUDD4 and MRDD1 in combination with standard nerve conduction tests should result in more accurate diagnosis of CTS in diabetic polyneuropathy patients.
These results could be helpful to overcome the diagnostic difficulty of CTS in patients with diabetic polyneuropathy.
患有糖尿病性多发性神经病的患者中，腕管综合征（CTS）的诊断较为困难，因为这两种病症可能以相似的方式影响正中神经传导。目前对于哪种电诊断测试在这些患者中更准确地确定 CTS 尚存在分歧。本研究旨在确定诊断糖尿病性多发性神经病患者 CTS 的最佳电诊断测试。
我们前瞻性地研究了 72 例 CTS 患者（140 只手）、32 例无 CTS 的糖尿病性多发性神经病患者（61 只手）、35 例伴有 CTS 的糖尿病性多发性神经病患者（62 只手）和 43 名健康对照者（86 只手）。对所有受试者均进行了标准神经传导研究、节段性和对比性正中神经传导测试。使用受试者工作特征（ROC）曲线确定每种测试用于诊断糖尿病性多发性神经病患者 CTS 的截断值的敏感性和特异性。
DPLR（截断值为 1，其敏感性为 90%，特异性为 81%）和 MUDD4（截断值为 0.35，其敏感性为 90%，特异性为 85%）的正中神经感觉潜伏期差值至第 4 指（中位数和尺神经）表现出最高的敏感性和特异性，用于诊断糖尿病性多发性神经病患者的 CTS。腕-手掌正中感觉传导速度（W-P SCV）和正中神经和桡神经感觉潜伏期差值至第 1 指（MRDD1）也表现出较高的敏感性和特异性。
节段性正中神经传导研究（如 DPLR 和 W-P SCV）和感觉对比测试（如 MUDD4 和 MRDD1）结合标准神经传导测试，应该可以更准确地诊断糖尿病性多发性神经病患者的 CTS。
这些结果可能有助于克服糖尿病性多发性神经病患者 CTS 的诊断困难。
