Evaluation of acute renal artery thrombosis or embolism with color Doppler sonography

Objective This study aimed to evaluate the value of color Doppler sonography (CDS) in the diagnosis of acute renal artery thrombosis or embolism (ARATE). Methods We retrospectively reviewed the CDS findings of 10 patients with ARATE, which were confirmed by the clinical data and digital subtraction angiography or computed tomography (n=8) or by the results of surgical pathology (n=2). We analyzed the echogenicity and size of the kidneys on gray-scale images and blood flow parameters of the main renal artery, renal vein, and the intrarenal artery (segmental or interlobar artery) of the kidneys on CDS in all cases. Results Four patients with acute main renal artery thrombosis (two transplanted kidneys and two native kidneys) correctly detected by CDS underwent emergency thrombolysis via renal artery. The results of CDS in six native kidneys with renal artery embolism included two cases with satisfactory CDS demonstrations, two cases with undetermined CDS findings, one case interpreted as severe renal artery stenosis, and one misdiagnosed case. Conclusions CDS is a useful imaging tool in the diagnosis of large renal infarcts caused by thrombosis or embolism in the main renal artery. However, small infarcts, which need other imaging modalities for further evaluation and confirmation, may be neglected by CDS.