Reply to Bastid et al.

We are grateful to Bastid and colleagues for their interest in our article. They suggest that in experienced hands, percutaneous color Doppler ultrasonography is a simple, low-cost technique that is very effective and does not require sedation. Unfortunately, we do not have access to their published article, as it is written in French.

Transabdominal ultrasound is undoubtedly less invasive and can be performed in the patient’s room. It has been used to evaluate the collateral vessels in cirrhotic patients and to assess the patency of distal splenorenal shunts. However, with regard to the sensitivity of the method for detecting spontaneous or surgical splenorenal shunts, ultrasound appears to be inferior to endoscopic ultrasonography (EUS) and computed tomography (CT), based on the published literature in English-language journals. So far as we are aware, there has only been one study directly comparing EUS with transabdominal ultrasonography for visualizing the portal venous system. Wiersema et al. [1] carried out duplex endosonography in 11 patients with suspected compromise of the intra-abdominal vessels, including surgical splenorenal shunts that transabdominal ultrasound had failed to detect. Duplex endosonography resulted in the correct diagnosis in 10 of the 11 patients (accuracy 0 % with transabdominal ultrasound versus 91 % with EUS; P < 0.001). In another study, dynamic CT demonstrated the anastomotic site following splenorenal shunt surgery in 13 patients, whereas Doppler ultrasound failed in all cases [2]. We showed that EUS is superior to contrast-enhanced CT for visualizing gastrorenal shunts. The detection rate of transabdominal ultrasound is reported to be in the range of 70 - 77 % [3] [4] - results that are not satisfactory, in our view. We would like to know whether it is possible to obtain an English translation of the study mentioned in the letter from Bastid et al.

Balloon-occluded retrograde transvenous obliteration (B-RTO) is a promising elective treatment for fundic varices associated with gastrorenal shunts [5] [6]. However, there is disagreement concerning the effectiveness of B-RTO in patients with acute bleeding. In our therapeutic protocol for bleeding fundic varices, temporary hemostasis is achieved by endoscopic treatments including cyanoacrylate injection or clipping before EUS examination with a curved linear-array (CLA) device and B-RTO. We are certain that EUS examination with a CLA device does not represent a risk after hemostasis.

We would also like to emphasize the potential of EUS for predicting the development of high-risk esophageal varices after B-RTO. It is well known that in some patients, esophageal varices develop or are exacerbated after successful B-RTO. This pathophysiology suggests a close association with the hemodynamics of the left gastric vein. We have previously reported that an examination with curved linear-array EUS using the color Doppler function allows detailed morphological observation and blood flow assessment in the left gastric vein [7].

We agree that further investigations are needed to compare the various aspects of EUS with ultrasound, CT, and magnetic resonance imaging - including the diagnostic accuracy, safety, and cost-effectiveness of these methods - to establish a diagnostic strategy for managing gastric fundic varices.

References

• 1 Wiersema M J, Chak A, Kopecky K K. et al . Duplex Doppler endosonography in the diagnosis of splenic vein, portal vein, and portosystemic shunt thrombosis.  Gastrointest Endosc. 1995;  42 19-26
• 2 Foley W D, Gleysteen J J, Lawson T L. et al . Dynamic computed tomography and pulsed Doppler ultrasonography in the evaluation of splenorenal shunt patency.  J Comput Assist Tomogr. 1983;  7 106-112
• 3 Ackroyd N, Gill R, Griffiths K. et al . Duplex scanning of the portal vein and portasystemic shunts.  Surgery. 1986;  99 591-597
• 4 Abdel W ahab, el-Kady N, Arafa N M. et al . Distal splenorenal shunts (Warren’s operation): B-mode and real time ultrasonographic assessment.  Egypt J Bilharz. 1979;  6 21-24
• 5 Matsumoto A, Hamamoto N, Toshiyuki N. et al . Balloon-occluded transvenous obliteration of high risk gastric varices.  Am J Gastroenterol. 1999;  94 643-649
• 6 Kakutani H, Sanada J, Tsukioka Y. et al . Transvenous obliteration of portosystemic shunt (TOPS) for control of solitary gastric varices.  Endoscopy. 1996;  28 S14
• 7 Hino S, Kakutani H, Ikeda K. et al . Hemodynamic analysis of esophageal varices using color Doppler endoscopic ultrasonography to predict recurrence after endoscopic treatment.  Endoscopy. 2001;  33 869-872