Department of Neurology, St. Vincent's University Hospital, Elm Park, Dublin 4, Ireland.
J Neurol. 2012 Jan;259(1):77-82. doi: 10.1007/s00415-011-6125-7. Epub 2011 Jun 8.
Adult-onset primary torsion dystonia (AOPTD) is an autosomal dominant disorder with markedly reduced penetrance. Sensory abnormalities are present in AOPTD and also in unaffected relatives, possibly indicating non-manifesting gene carriage (acting as an endophenotype). The temporal discrimination threshold (TDT) is the shortest time interval at which two stimuli are detected to be asynchronous. We aimed to compare the sensitivity and specificity of three different TDT tasks (visual, tactile and mixed/visual-tactile). We also aimed to examine the sensitivity of TDTs in different AOPTD phenotypes. To examine tasks, we tested TDT in 41 patients and 51 controls using visual (2 lights), tactile (non-painful electrical stimulation) and mixed (1 light, 1 electrical) stimuli. To investigate phenotypes, we examined 71 AOPTD patients (37 cervical dystonia, 14 writer's cramp, 9 blepharospasm, 11 spasmodic dysphonia) and 8 musician's dystonia patients. The upper limit of normal was defined as control mean +2.5 SD. In dystonia patients, the visual task detected abnormalities in 35/41 (85%), the tactile task in 35/41 (85%) and the mixed task in 26/41 (63%); the mixed task was less sensitive than the other two (p = 0.04). Specificity was 100% for the visual and tactile tasks. Abnormal TDTs were found in 36 of 37 (97.3%) cervical dystonia, 12 of 14 (85.7%) writer's cramp, 8 of 9 (88.8%) blepharospasm, 10 of 11 (90.1%) spasmodic dysphonia patients and 5 of 8 (62.5%) musicians. The visual and tactile tasks were found to be more sensitive than the mixed task. Temporal discrimination threshold results were comparable across common adult-onset primary torsion dystonia phenotypes, with lower sensitivity in the musicians.
成人发作性原发性扭转痉挛（AOPTD）是一种常染色体显性遗传病，外显率明显降低。AOPTD 患者和未受影响的亲属都存在感觉异常，这可能表明非显性基因携带（作为一个内表型）。时间辨别阈值（TDT）是两个刺激被检测为不同步的最短时间间隔。我们旨在比较三种不同 TDT 任务（视觉、触觉和混合/视觉-触觉）的敏感性和特异性。我们还旨在研究 TDT 在不同 AOPTD 表型中的敏感性。为了检查任务，我们使用视觉（2 个光源）、触觉（无痛电刺激）和混合（1 个光源，1 个电刺激）刺激对 41 名患者和 51 名对照进行了 TDT 测试。为了研究表型，我们检查了 71 名 AOPTD 患者（37 名颈肌痉挛、14 名书写痉挛、9 名眼睑痉挛、11 名痉挛性发音障碍）和 8 名音乐家痉挛患者。正常上限定义为对照组平均值+2.5SD。在痉挛患者中，视觉任务检测到 41 名患者中的 35 名（85%），触觉任务检测到 41 名患者中的 35 名（85%），混合任务检测到 41 名患者中的 26 名（63%）；混合任务的敏感性低于其他两种任务（p=0.04）。视觉和触觉任务的特异性均为 100%。37 名颈肌痉挛患者中的 36 名（97.3%）、14 名书写痉挛患者中的 12 名（85.7%）、9 名眼睑痉挛患者中的 8 名（88.8%）、11 名痉挛性发音障碍患者中的 10 名（90.1%）和 8 名音乐家痉挛患者中的 5 名（62.5%）存在异常 TDT。视觉和触觉任务比混合任务更敏感。在常见的成人发作性原发性扭转痉挛表型中，TDT 结果具有可比性，音乐家的敏感性较低。
