Diagnosis of Rectal Varices via Color Doppler Ultrasonography

Abstract

There has been no report on the hemodynamic evaluation of rectal varices by percutaneous color Doppler ultrasonography. Here, we report the usefulness of color Doppler ultrasonography for this purpose. Color Doppler ultrasonography was performed in 44 patients: 31 patients with portal hypertension, 7 with liver cirrhosis (LC) without portal hypertension, and 6 non-LC patients. We examined color flow images and measured velocity of blood flow in rectal varices using fast-Fourier transform (FFT) analysis. Next, we performed colonoscopy on these 44 patients as follow-up to confirm findings by color Doppler. Endoscopic findings of rectal varices were evaluated according to the grading system outlined in "The General Rules for Recording Endoscopic Findings of Esophageal Varices" prepared by the Japanese Research Committee on Portal Hypertension. Rectal varices were shown by Doppler color flow images in 27 of the 31 patients (87.1%) with portal hypertension. Blood flow velocity in those 27 rectal varices ranged from 2.0 to 11.6 cm/s (mean 6.5 +/- 2.4 cm/s). Rectal varices were observed in all 27 of these cases by colonoscopy. On the other hand, rectal varices were not observed by colonoscopy in the 7 LC patients without portal hypertension and the 6 non-LC patients not shown to have rectal variceal blood flow via color Doppler ultrasonography. Sensitivity, specificity, and accuracy were 27/27 (100%), 17/17 (100%), 44/44 (100%), respectively, for detection of rectal varices with color Doppler ultrasonography. Next, we compared velocities of rectal varices obtained by color Doppler ultrasonography with colonoscopic findings. Mean velocity (7.1 +/- 2.3 cm/s) in Cb variceal cases (N = 20) was significantly higher than that (4.9 +/- 1.7 cm/s) in the Cw rectal variceal cases (N = 7) (P < 0.05). Mean velocity (8.5 +/- 2.0 cm/s) in the RC-positive cases (N = 9) was significantly higher than that (5.4 +/- 1.8 cm/s) in RC-negative cases (N = 18) (P < 0.01). Mean velocity (9.8 +/- 1.6 cm/s) in rectal bleeding cases (N = 3) was significantly higher than that (6.1 +/- 2.1 cm/s) in patients without bleeding (N = 24) (P < 0.05). Seven days after endoscopic injection sclerotherapy (EIS) treatment, color Doppler ultrasonography showed an extreme decrease in blood flow in all three rectal varices in comparison with values before EIS. Color Doppler ultrasonography can be considered a very useful noninvasive tool for diagnosis of rectal varices.