Verdugo R, Ochoa J L
Department of Neurology, Good Samaritan Hospital and Medical Center, Oregon Health Sciences University, Portland 97210.
Brain. 1992 Jun;115 ( Pt 3):893-913. doi: 10.1093/brain/115.3.893.
The quantitative somatosensory thermotest (QST) assesses the function of afferent channels concerned with sensory submodalities served by small calibre fibres. Measured ramps of ascending or descending temperature are applied to the skin through a Peltier contact thermode, and detection thresholds are recorded as the subject signals the onset of a particular sensation. The present study describes underlying principles, methodological aspects and normal reference values for the QST. In patients, measurement of thresholds for cold sensation, warm sensation, cold-induced pain and heat-induced pain, applied to 465 individuals, yielded 13 abnormal patterns segregated into three main groups: (i) thermal (cold or warm) hypoaesthesia; (ii) thermal hyperalgesia (abnormally reduced threshold for cold and/or heat induced pain); (iii) thermal hypoaesthesia combined with thermal hyperalgesia. Critical analysis of these results yielded a number of observations of general relevance: (i) thermal specific (warm or cold) hypoaesthesia and thermal (heat or cold) hyperalgesia may occur in the absence of hypoaesthesia for tactile submodalities served by large calibre afferents; (ii) cold hypoaesthesia and warm hypoaesthesia may dissociate from each other; (iii) thermal pain hyperalgesias may occur in the absence of hypoaesthesias for specific cold or warm sensations; (iv) cold hyperalgesia and heat hyperalgesia may dissociate from each other. Thus, a negative routine sensory examination and unimpaired sensory nerve action potentials do not exclude possible somatosensory dysfunction. Furthermore, while most methods of sensory testing only document normality or deficit, the QST permits additional documentation of hyperalgesia, a positive sensory phenomenon that implies unusual pathophysiologies such as sensitization of receptors, central hyperexcitability, disinhibition or, possibly, ectopic nerve impulse discharge. This psychophysical test does not specify the level within afferent channels, between skin and brainmind, where the abnormality resides. It is recommended that the QST for all four thermal specific and thermal pain functions be incorporated in routine neurological assessment.
定量体感温度测试（QST）评估与小口径纤维所服务的感觉亚模式相关的传入通道功能。通过珀尔帖接触式热电极将上升或下降温度的测量斜坡施加于皮肤，并记录检测阈值，即受试者发出特定感觉开始信号时的阈值。本研究描述了QST的基本原理、方法学方面以及正常参考值。在患者中，对465名个体进行冷觉、温觉、冷诱发痛和热诱发痛阈值的测量，产生了13种异常模式，分为三个主要组：（i）热觉（冷或温）减退；（ii）热觉过敏（冷和/或热诱发痛阈值异常降低）；（iii）热觉减退与热觉过敏并存。对这些结果的批判性分析得出了一些具有普遍相关性的观察结果：（i）热觉特异性（温或冷）减退和热觉（热或冷）过敏可能在由大口径传入纤维服务的触觉亚模式无减退的情况下出现；（ii）冷觉减退和温觉减退可能相互分离；（iii）热痛觉过敏可能在特定冷觉或温觉无减退的情况下出现；（iv）冷觉过敏和热觉过敏可能相互分离。因此，常规感觉检查阴性和感觉神经动作电位正常并不能排除可能的体感功能障碍。此外，虽然大多数感觉测试方法仅记录正常或缺陷，但QST允许额外记录痛觉过敏，这是一种阳性感觉现象，意味着存在异常的病理生理学，如受体敏化、中枢性过度兴奋、去抑制或可能的异位神经冲动发放。这种心理物理学测试并未明确异常所在的传入通道内、皮肤与脑/心智之间的水平。建议将所有四种热觉特异性和热痛功能的QST纳入常规神经学评估。
