The role of imaging techniques in renal transplantation.

Our aim is to review the utility of the different imaging techniques in the field of renal transplantation (RT). A total of 500 potential RT recipients have been evaluated and were included in the waiting list. From 1978 to 2003, a total of 900 RT recipients were clinically followed-up and different imaging techniques assessed. The main indications for the different techniques were: (1) MR angiography to establish the vascular anatomy of the living donor with 95% accuracy for the detection of multiple renal vessels. (2) Abdominal ultrasound of the donor in order to detect lithiasis, incidental renal tumors or anatomic anomalies. (3) Vascular evaluation of the recipients was essential considering the aging character of this population. X-ray film of the abdomen was a routine technique. Doppler ultrasound (DOP-US) of the iliac vessels and an angiographic study (DSA, CT, MR) of the iliac and splenic arteries were indicated only in selected cases. (4) DOP-US was useful in the diagnosis of graft dysfunction after RT. It allowed the exclusion of thrombosis and urinary obstruction, and was useful to distinguish between acute tubular necrosis, cyclosporine nephrotoxicity and acute rejection (AR). (5) Finally, ultrasound was used as a percutaneous approach to pyelocaliceal systems of grafts affected by ureteral stenosis or fistula and for draining fluid collections after RT (lymphocele, abscess, hematoma or urinoma).