Sonography in renovascular hypertension

Abstract

Objective. To familiarize practitioners with different sonographic manifestations of renal artery compromise and the sonographic techniques for renal artery imaging. Methods. Approximately 1500 examinations evaluating for renal artery disease are performed in our vascular laboratory every year. Most of the patients have the symptoms of hypertension (possibly related to renovascular etiology) and renal insufficiency. From our cumulative experience, the optimal scanning techniques are defined for each renal artery, for extrarenal versus intrarenal vascular evaluation, and for patients with different body habitus. We have also tabulated our technical success rate. Cases with sonographic evidence of renal artery compromise are identified. The validity, sensitivity, and specificity of different parameters are examined. Results. We achieve an approximately 75% to 80% success rate in obtaining technically adequate studies. We have not found the tardus-parvus waveform evaluation to be as valuable as direct interrogation of the renal artery. Conclusions. Duplex/color Doppler sonography serves a vital role in the diagnosis of renal artery stenosis and occlusion; it has an excellent correlation with contrast-enhanced angiography. It is also used for intraoperative or postrevascularization surveillance to show evidence of recurring stenosis, thrombosis, and other complications.