^(99)Tc^m-DTPA肾动态显像对移植肾上尿路梗阻的诊断及鉴别诊断

Renal Dynamic Imaging in Diagnosis of Upper Urinary Tract Obstruction in Transplanted Kidney With ^(99)Tc^m-DTPA

对88例肾移植受者作110次99Tcm-DTPA肾动态显像,发现上尿路梗阻的肾动态显像主要为两类:一是普通型,其特征是灌注期和摄取早期肾盂范围的肾实质内早期放射性稀疏区伴随之后的肾盂及输尿管内显像剂滞留以及由此产生的梗阻型肾图曲线;二是肾小管梗阻型,特征是肾皮质放射性滞留及髓质全程放射性稀疏而呈特征性的"空心"肾。非梗阻性肾盂扩张的肾动态表现类似于普通型上尿路梗阻;急性排斥、急性肾小管坏死等也出现类梗阻曲线,但其放射性滞留部位在肾皮质,且多伴有其它功能损害。本研究结果提示,肾盂扩张和梗阻型肾图曲线不是上尿路梗阻的可靠依据,而肾盂范围的肾实质早期放射性稀疏及肾盂输尿管放射性滞留才具有诊断价值,唯一需要鉴别的是功能性梗阻,对此利尿试验可予以鉴别;对于肾小管梗阻型,特征性的"空心"肾有较高诊断价值。

Renal dynamic imaging with 99TcmDTPA is performed on 88 cases (110 times) transplanted kidney. Two kinds of renal scintigraphic are observed in recipients with supravesical obstruction of the graft. The first is, the regular type which is specifically characterized by activity defect area in kidney parenchyma during early uptake period followed by ureteropelvic retention.The second is,the tubular type which is featured by cortical retention and attenuation in collecting system during the whole test period with a special sign,'vacant kidney' Nonobstructive dilated calyces show similar signs as the regular type.Acute rejection reaction and tubule necrosis demonstrate obstructive time activity curves.However, the radioactivity retention appears in cortex. It is suggested that dilated calyces and obstructive renogram may be not feasible evidences for upper urinary tract obstruction. The signs of radioactivity attenuation in kindney parenchyma during early uptake period followed by ureteropelvic retention may be more valuable. For tubular obstruction,specified 'vacant kidney' is the characteristic sign which may be very helpful for the diagnosis.