Mizuiri S, Hayashi I, Takano M, Ban R, Ohara T, Sasaki Y, Hasegawa A
Department of Nephrology, Toho University, Tokyo, Japan.
J Nucl Med. 1994 Jan;35(1):84-9.
To determine the usefulness of fractional mean transit time (MTT) in the differential diagnosis of postrenal transplant complications, 99mTc-DTPA was used to evaluate differences in MTT between the outer zone (cortical nephron) and middle zone (juxtamedullary nephron, calcyces and cortical nephron) of the kidney. It is well known that acute rejection is characterized by delayed cortical transit time, whereas cortical nephron function is well maintained and juxtamedullary function is impaired after renal ischemia.
Technetium-99m-DTPA fractional MTT was determined by deconvolution analysis of 89 renograms obtained within 5 days of the date of kidney graft biopsy and evaluation.
Outer zone MTT was significantly shorter than middle zone MTT in normals (2.7 +/- 0.4 versus 3.0 +/- 0.6 min, n = 22, p < 0.001), acute tubular necrosis (3.4 +/- 1.1 versus 3.6 +/- 1.4 min, n = 19, p < 0.01), chronic rejection (3.9 +/- 1.5 versus 5.0 +/- 2.3 min, n = 14, p < 0.001) and obstruction (4.1 +/- 0.6 versus 8.9 +/- 3.4 min, n = 13, p < 0.001). In contrast, outer zone MTT was significantly longer than middle zone MTT in acute rejection (4.8 +/- 3.2 versus 4.2 +/- 2.5 min, n = 21, p < 0.05).
Fractional MTT was demonstrated to be useful in differentiating acute rejection and ATN in transplanted kidneys.
为了确定分数平均通过时间（MTT）在肾移植后并发症鉴别诊断中的作用，使用99mTc-DTPA评估肾脏外层区域（皮质肾单位）和中层区域（近髓肾单位、肾盏和皮质肾单位）之间MTT的差异。众所周知，急性排斥反应的特征是皮质通过时间延迟，而肾缺血后皮质肾单位功能保持良好，近髓功能受损。
通过对肾移植活检和评估日期5天内获得的89份肾图进行反卷积分析，确定锝-99m-DTPA分数MTT。
在正常情况下（2.7±0.4对3.0±0.6分钟，n = 22，p < 0.001）、急性肾小管坏死（3.4±1.1对3.6±1.4分钟，n = 19，p < 0.01）、慢性排斥反应（3.9±1.5对5.0±2.3分钟，n = 14，p < 0.001）和梗阻（4.1±0.6对&.9±3.4分钟，n = 13，p < 0.001）中，外层区域MTT明显短于中层区域MTT。相比之下，在急性排斥反应中（4.8±3.2对4.2±2.5分钟，n = 21，p < 0.05），外层区域MTT明显长于中层区域MTT。
分数MTT被证明有助于鉴别移植肾中的急性排斥反应和急性肾小管坏死。
