Wang S J, Lin W Y, Hsu C Y, Kao C H, Chang C P, Lan J L
Department of Nuclear Medicine, Taichung Veterans General Hospital, Taiwan, Republic of China.
Gaoxiong Yi Xue Ke Xue Za Zhi. 1993 Aug;9(8):454-9.
The histologic picture of polymyositis or dermatomyositis is characterized by muscle fiber degeneration, which is assumed to be caused by a circulatory abnormality. To verify this assumption, we measured the muscle blood flow in patients with polymyositis (or dermatomyositis) and in normal subjects using the inert gas Xe-133. Sixteen patients and 30 age-matched normal volunteers were studied. Muscle blood flow was measured with Xe-133 dissolved in isotonic saline as described by Lassen et al. (1964) and Pozderac et al. (1975). Data were acquired in the frame mode after intramuscular injection (anterior tibial muscle) of 0.3 mCi of Xe-133 in 0.2ml of saline for 20 min. A computer routine was used to calculate the clearance half time (T 1/2) in min and flow rate (Q) in ml/100 gm tissue/min. The student's t test was used to test statistical significance. Our preliminary results suggest: 1. The muscle blood flow in patients with polymyositis and dermatomyositis was significantly lower than the corresponding normal control levels. 2. This findings may be due to decreased in muscle capillary 3. Further studies are warranted to obtain a conclusive understanding of the pathogenesis of polymyositis and dermatomyositis.
多发性肌炎或皮肌炎的组织学表现以肌纤维变性为特征，推测这是由循环异常引起的。为了验证这一假设，我们使用惰性气体Xe - 133测量了多发性肌炎（或皮肌炎）患者和正常受试者的肌肉血流量。研究了16例患者和30名年龄匹配的正常志愿者。按照Lassen等人（1964年）和Pozderac等人（1975年）所述，用溶解于等渗盐水中的Xe - 133测量肌肉血流量。在肌肉内注射（胫前肌）0.2ml盐水中含0.3mCi的Xe - 133后20分钟，以帧模式采集数据。使用计算机程序计算清除半衰期（T1/2，单位为分钟）和流速（Q，单位为ml/100克组织/分钟）。采用学生t检验来检验统计学显著性。我们的初步结果表明：1. 多发性肌炎和皮肌炎患者的肌肉血流量显著低于相应的正常对照水平。2. 这一发现可能是由于肌肉毛细血管减少所致。3. 有必要进行进一步研究以对多发性肌炎和皮肌炎的发病机制有确凿的认识。
