In our patient, abdominal ultrasound and retrograde pyelography raised the suspicion of a left renal tumour but failed to detect the horseshoe kidney. To determine the tumour resectability and to visualise the renal vessels and excretory system, a biphasic multislice CT was performed (Fig. 1). On this occasion the diagnosis of a horseshoe kidney with a parenchymal isthmus and multiple arteries was made (Figs 1a,1c). The left renal mass presented as an infiltrating tumour originating from the renal pelvis (Fig. 1b). The excretion phase revealed two single ureters (Fig. 1d). Due to impaired function of the non-tumour-bearing right renal unit, a large part of the parenchymal isthmus had to be preserved during left nephroureterectomy. Detailed illustration of the renal vessels by helical CT imaging proved to be indispensable for the planning of nephron-sparing surgery.
Multislice CT provides superior characterisation of the renal anatomy with little patient discomfort at reasonable cost. This single imaging modality should eventually replace conventional radiological studies for preoperative evaluation of renal masses.
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URL: | https://www.eurorad.org/case/1690 |
DOI: | 10.1594/EURORAD/CASE.1690 |
ISSN: | 1563-4086 |