Intrarenal varices : Demonstration by color doppler sonography

A 53 year old woman found to have microscopic hematuria during physical examination was referred for further examination. She had no abnormal laboratory findings other than microhematuria of grade 1+. During B-mode ultrasonography using a 3.5 MHz transducer, a hypoechoic curved luminal area was observed in the renal sinus at the lower pole of the left kidney (Fig. 1). During color Doppler sonography, color display was observed corresponding to this hypoechoic area, and the duplex pattern consistent with venous flow (Vmax, 23 cm/s) was detected on FFT analysis (Fig. 2). On the basis of these findings, this abnormal blood flow strongly suggested renal varices. Therefore, 3D color Doppler sonography was performed. 3D images were obtained from cine loop data using the built-in computer of GE Yokogawa LOGIQ 500 (Hino City, Tokyo, Japan) and the maximal intensity method. 3D images could be displayed 5 s after scanning. Dilated or tortuous configuration of abnormal blood flow at the lower pole of the left kidney could be recognized objectively by 3D imaging, as could normal renal blood flow (Fig. 3). MR imaging showed a signal void on T1-weighted and T2-weighted images of the lesion between the sinus at the lower pole of the kidney and the hilum. This flexed and tortuous vascular structure continued to the left renal vein. On the basis of these diagnostic imaging findings, the patient was diagnosed as having intrarenal varices; however, renal angiography was performed to establish a definitive diagnosis. Since marked findings were not observed during the early phase of left renal arteriography, the presence of arteriovenous malformation or Received January 12, 1998, from the Departments of Radiology (M.T., S.H., H.U.) and Oncoradiology (H.O., T.H., R.Y.), Nara, Japan. Revised manuscript accepted for publication May 4, 1998. Address correspondence and reprint requests to Miho Takahashi, MD, Department of Radiology, Nara Medical University, 840 Shijocho, Kashihara City, Nara, 634-8522 Japan. ABBREVIATIONS