原發性顫抖症：臨床分析及單光子射出性斷層掃描 ( 99m Tc-ECD SPECT)的表現 摘 要 背景 原發性顫抖症(Essential Tremor)是動作障礙疾病中最常見的。診斷是根據臨床的表現，而它的治療主要是症狀改善。原發性顫抖症的病因不明。有一些證據認為橄欖核-小腦視丘腦皮質傳導迴路是產生原發性顫抖症的重要原因。先前以正子電腦斷層掃描儀(positron emission tomography, PET)的研究顯示原發性顫抖症患者局部腦血流的改變。不過與單光子射出性斷層掃描(single photon emission computed tomography, SPECT)比較，正子掃描無法廣泛的被應用。這個研究的目的是要評估使用technetium-99m ethyl cysteinate dimer (99m Tc ECD)單光子射出性斷層掃描來偵測原發性顫抖症患者腦部灌流改變的潛在可行性。 方法 在這個研究中，針對25位有正常腦部核磁共振影像的原發性顫抖症患者實施99m Tc ECD單光子射出性斷層掃描檢查來偵測局部腦部血流的狀態。 結果 在視丘、基底核、顳葉及額葉有相對較低灌流的發現。在這些區域，以較厲害顫抖肢體的對側視丘有著顯著減少的灌流。在基底核或小腦部位的腦血流差異，則沒有統計學上的意義。局部腦血流的減少與顫抖的嚴重度及顫抖的存在期間並無相關。 結論 我們的研究顯示原發性顫抖症患者視丘部位的血液灌流降低可以99m Tc ECD單光子射出性斷層掃描檢查來偵測出。這個結果暗示著視丘可能是產生或調節原發性顫抖症的重要部位。此外，這個發現給我們一個觀點，就是以單光子射出性斷層掃描的檢查來探查原發性顫抖症或其他種類的顫抖症是合適而且便利的工具。; Essential tremor: clinical analysis and 99m Tc-ECD SPECT findings ABSTRACT Background Essential tremor (ET) is the most prevalent movement disorder. The diagnosis is based on clinical findings, and its treatment is mainly symptomatic. The pathogenesis of ET is unknown. Some pieces of evidence suggest that the olivo-cerebello-thalamo-cortical circuitry is pivotal for the development of essential tremor. Previous studies with positron emission tomography (PET) have revealed an alternation of the regional cerebral blood flow (rCBF) in ET patients. However PET is not universally available as compared with single photon emission computed tomography (SPECT). The aim of this study was to evaluate the potential usefulness of technetium-99m ethyl cysteinate dimer (99m Tc ECD) SPECT in detecting the possible alternation of brain perfusion in patients with ET. Methods In this study, 25 ET patients with normal findings on brain magnetic resonance imaging (MRI) were examined with a 99m Tc ECD SPECT of the brain to detect the status of the regional cerebral blood flow. Results Relative hypoperfusion was found in the thalamus, basal ganglia, temporal lobe, and frontal lobe. Among these spots, only the perfusion of the thalamic region contralateral to the more vigorous tremor side was found to be significantly diminished. No statistically significant difference was present in either the basal ganglia or the cerebellum. The decrease in rCBF was irrelevant to the tremor severity and duration of tremor. Conclusion Our study demonstrates that hypoperfusion of the thalamic region can be detected by 99mTc-ECD brain SPECT in patients with ET, which implies that the thalamus might be crucial for the generation or modulation of ET. In addition, the finding also strengthens the viewpoint that this SPECT technique is an appropriate and convenient tool for the investigation of ET or other sorts of tremor.
