J Clin Ultrasound 20:427-432, September 1992 0 1992 by John Wiley & Sons, Inc. CCC 0091-2751/92/070427-06$04.00
Portosystemic Collateral Shunts Originating from the Left Portal Veins in Portal Hypertension: Demonstration by Color Doppler Flow Imaging Nobuyuki Sugiura, MD,* Eii Karasawa, MD,? Naoki Saotome, MD,? Makoto Miki, MD,? Shouichi Matsutani, MD,* Masao Ohto, MD*
Abstract: Color Doppler flow imaging was performed in 121 patients with portal hypertension. Portosystemic collateral shunts originating from the left portal veins were seen in 41 of the patients. A single collateral shunt was seen in 27 of these, and multiple collateral shunts were seen in the other 14. Collateral shunts running in the ligamentum teres were seen in 26 of the 41 patients; the veins ran through the liver parenchyma in 25 of these. B-mode ultrasound imaging could not clearly demonstrate vascular structures in 55% of the collateral shunts. Color Doppler flow imaging provided a clear picture of the course of the portosystemic collateral shunts originating from the left portal vein. 0 1992 John Wiley & Sons, Inc. Indexing Words: Portosystemic collateral shunts * Paraumbilical vein * Color Doppler flow imaging * Portal hypertension
Real-time B-mode ultrasound and pulsed Doppler ultrasound have been increasingly used as noninvasive procedures for examining the portal venous hemodynamics in portal hypertension.' Color Doppler flow imaging, which displays the blood flow in a color-coded manner, has also been applied to the abdomen, and its clinical potential has been discussed.2 Color Doppler flow imaging can demonstrate blood vessel patency and blood flow direction in a short time, and it can also detect a vessel not shown in B-mode ultrasound imaging by means of its color-coding feature. Color Doppler flow imaging has come to be considered very useful for the identification of vessels. Portosystemic collateral shunts originating from the left portal veins in portal hypertension have been investigated by various imaging mod a l i t i e ~ . ~There - ~ are, however, few reports on From the The First Department of Internal Medicine, Chiba University School of Medicine, Chiba, Japan, and The Department of Internal Medicine, Yokohama Higashi National Hospital, Kanagawa, Japan. For reprints contact Nobuyuki Sugiura, MD, The First Department of Internal Medicine, Chiba University School of Medicine, 1-8-1 Inohana, Chiba 260, Japan.
collateral shunts running through the liver parenchyma and draining into the paraumbilical veins in the falciform ligament. In this article, we report a color Doppler flow imaging investigation performed to demonstrate the portosystemic collateral shunts originating from the left portal veins in portal hypertension and the detectability of those in comparison with B-mode ultrasound imaging. MATERIALS AND METHODS
Color Doppler flow imaging was performed in 121 patients with liver cirrhosis and 3 with idiopathic portal hypertension during the period from April 1989 to January 1990 at the Yokohama Higashi National Hospital. This sample was comprised of 85 men and 36 women, with an age range of 37 to 79 years. Diagnosis was made based on histological findings only in 48 patients and on both clinical findings and imaging in the other 63. The equipment used was a SSA-270A scanner with a 3.75 MHz sector array probe and a 3.75 MHz convex array probe (Toshiba, Tokyo, Japan). All patients were first examined by B-mode ultrasound imaging, and then by color 427
SUGIURA ET AL.
428
compared with those demonstrated by B-mode ultrasound imaging.
TABLE 1 Courses of Portosystemic Collateral Shunts (PCS) Originating from the Left Portal Vein Course
No. of PCS
RESULTS
____
~
A
B
A+ B
(%)
(%1
(%)
No. of Patients
Single Multiple Two Three Four Mu.
27 14 8 3 1 2
14 (51.9) 2 (14.3) 0 0 0 2
13 (48.1) 2 (14.3) 2 0 0 0
Total
41
16 (39.0)
15 (36.6)
Portosystemic collateral shunts from the left portal veins were demonstrated in 41 (34%) of the 121 patients studied (Table 1). These collateral shunts showed a single course in 27 (66%)patients, and a multiple course in the remaining 14 (34%).Those with a single course were classified as course A in 14 (52%)of the 27 patients, and as course B in the remaining 13 patients (48%). Those having a multiple course were respectively classified as course A, B, or both in 2, 2, and 10 of the 14 patients, respectively. The routes numbered two in 8 patients, three in 3 patients, and 4 in l patient. The routes-showed a multiple tortuous tubular structure in the remaining 2 patients. Collateral shunts running in the ligamentum teres were seen in 26 of the 41 patients, and the veins ran through the liver parenchyma in 25 of these. The detectability of portosystemic collateral shunts originating from the left portal veins using B-mode ultrasound imaging was examined in the 39 patients that did not show a multiple tortuous tubular structure with color Doppler imaging (Table 2). An anechoic vascular structure in the ligamentum teres was clearly seen in 15 of the 24 collateral shunts classified as course A, but there was some difficulty with the visualization in the remaining 9 shunts. An anechoic vascular structure running between the umbilical portion of the left portal vein and the liver surface was seen in 14 of the 32 shunts classified as course B, but this was demonstrated in only a portion of the course in the remaining 18 shunts (Figure 2). B-mode ultrasound imaging could not clearly demonstrate vascular structures in 55% of the collateral shunts originating from the left portal veins.
10 (71.4) 6 3 1 0 10 (24.5)
MU.: multiple tortuous venous Structure.
Doppler flow imaging. The ultrasonographers were skilled with both ultrasound methods and were the same in both ultrasound imaging trials. Portosystemic collateral shunts originating from the left portal veins were classified into two types according to their course between the umbilical portion of the left portal veins and the anterior liver surface (Figure 1).
A. Course in or along the ligamentum teres. B. Course through the liver parenchyma. Vessels showing color-coded blood flows in either or both of these courses were regarded as portosystemic collateral shunts. On B-mode ultrasound imaging, tubular anechoic structures detected serially in the same sites were also regarded as collateral shunts. The time needed to detect these courses was either shorter in color Doppler flow imaging than in B-mode ultrasound imaging or was the same with both ultrasound methods. The features of portosystemic collateral shunts originating from the left portal veins were studied by color Doppler flow imaging, and
TABLE 2 Detectability of PCS with B-Mode Ultrasound Imaging PCS Course
A Single Multiple
B Single Multiple
No. of Veins
14 10
13 19
Demonstration of Vascular Structure Demonstrable
Unclear
Undernonstrable
(W
(%) 5 (35.7) 1 (10.0)
1 (7.1) 2 (20.0)
8 (61.5) 7 (70.0)
(YO)
Demonstrable
Demonstrable in part
% 6 (46.2) 8 (42.1)
7 (53.8) 11 (57.9)
%
JOURNAL OF CLINICAL ULTRASOUND
FIGURE 1. (b) Color Doppler image shows a red color-coded hepatofugal flow of PCS running in the ligamentum teres (course A).
-
Lig.Teres
FIGURE 1. Courses of portosysternic collateral shunts originating from the left portal veins (LPV). (a) The figure shows course A and 6. (A) Course in or along the ligamentum teres. (B)Course through the liver parenchyma.
FIGURE 1. (c) Color Doppler image shows an orange color-coded hepatofugal flow of PCS running through the liver parenchyma (course B). VOL. 20,
NO. 7, SEPTEMBER
1992
429
430
SUGIURA ET AL.
FIGURE 2. A case with PCS undemonstrated by 6-mode ultrasound imaging. (a) 6-mode image did not show a serial vascular structure between the left portal vein and the liver surface. (b) Color Doppler image shows a red color-coded flow between the left portal vein and the liver surface. JOURNAL OF CLINICAL ULTRASOUND
PORTOSYSTEMIC COLLATERAL SHUNTS
DISCUSSION Martin and Tudor' reported that paraumbilical veins were divided into three groups: Burrow's veins and Sappey's superior and inferior veins. Burrow's veins ascend from the epigastric veins along the umbilical vein and terminate independently in the middle third of the umbilical vein, failing to enter the portal system directly. Sappey's superior veins drain the median part of the diaphragm, traverse the upper part of the falciform ligament to reach the liver surface, and enter the sublobular divisions of the portal veins. Usually, paraumbilical veins that are discussed in portal hypertension correspond to those that were designated as Sappey's inferior veins. These veins communicate with epigastric and cutaneous veins, extend from the umbilical region to the liver, and have communications with the portal system in a variety of ways.7 Paraumbilical veins develop into collateral shunts originating from the left portal veins in portal hypertension. Other collateral shunts originating from the left portal veins appear as reopened umbilical veins. Until now, collateral shunts originating from the left portal veins were mostly designated as umbilical veins.4 Lin et al.7 studied whether collateral veins between the left portal veins and systemic veins in patients with portal hypertension actually represented reopened umbilical veins and paraumbilical veins; they reported that both served as part of a portosystemic collateral shunt in portal hypertension. On the other hand, Lafortune et a1.' reported, based on postmortem examinations, that such veins were all defined as paraumbilical veins around the umbilical vein. In imaging studies including ultrasound, it was impossible to determine whether a collateral vein in the ligamenturn teres was a paraumbilical vein or a reopened umbilical vein. We divided portosystemic collateral shunts originating from the left portal vein into two types according to their course: a course that ran in or along the ligamentum teres, and a course that ran through the liver parenchyma and the falciform ligament. Although portosystemic collateral shunts originating in the left portal vein running in the ligamentum teres observed by ultrasound or pulsed Doppler ultrasound have been studied exten~ i v e l y , ~the , ' ~ collateral veins running through the liver parenchyma have received little attention." This is because the vascular structure of the collateral vein running through the liver parenchyma is difficult to observe serially with VOL. 20, NO. 7, SEPTEMBER 1992
43 1
B-mode ultrasound imaging because it meanders beneath the liver surface. However, when an anechoic vascular structure on B-mode examination has a blood flow, it is easily visualized by its color-coded flow with color Doppler flow imaging. When a vessel with a color-coded flow is serially displayed from the umbilical portion of the left portal vein to the anterior liver surface, it is a portosystemic collateral shunt. In this study, the portosystemic collateral shunts running through the liver parenchyma were seen in 13 of 27 patients with a single collateral shunt and in 12 of 14 with multiple collateral shunts. Lafortune et a1.8 reported that paraumbilical veins found in patients with portal hypertension increased in number and diameter. We observed multiple-course paraumbilical veins in 34% of the 41 patients, and the maximum number of courses was four. To identify a portosystemic collateral shunt originating from the left portal vein, such invasive modalities as surgical portography, percutaneous transhepatic p~rtography,~ and arteriop ~ r t o g r a p h yas , ~ well as such noninvasive procedures as B-mode ultrasound imaging,5 X-ray computed tomography,13magnetic resonance imaging,14 and pulsed Doppler ultrasound,15 have been used to date. Pulsed Doppler ultrasound has been particularly useful in the examination of portal venous hemodynamics under physiological conditions.16 In the present study, B-mode ultrasound imaging was much less effective in detecting portosystemic collateral shunts originating from the left portal veins than we expected, but color Doppler flow imaging proved to be very practical for this purpose. The detection of transhepatic portosystemic collateral shunts in portal hypertension is difficult, and we must be careful with the evidence of transhepatic portosystemic collateral shunts, especially when they remain unidentified by B mode ultrasound.
REFERENCES Patriquin H, Lafortune M, Burns PN, Dauzat M: Duplex Doppler examination in portal hypertension: Technique and anatomy. AJR 149:71-76, 1987. Scoutt LM, Zawin ML, Taylor KJW: Doppler US. Part 11. Clinical applications. Radiology 174:309319, 1990. Hoevels J, Lunderquist A, Tylen US: Porto-systemic collaterals in cirrhosis of the liver. Actu Rudiol Diagnosis 20:865-877, 1979. Burchell AR, Panke WF, Moreno AH, Rousselot LM: The patent umbilical vein in portal hyperten-
432
SUGIURA ET AL.
sion. Surg Genecol Obstet 130:77-86, 1970. 5. Glazer GM, Laing FC, Brown TW, Gooding GAW: Sonographic demonstration of portal hypertension: The patent umbilical vein. Radiology 136:161-163, 1980. 6. Martin BF, Tudor RG. The umbilical and paraumbilical veins of man. J Anat 130:305-322, 1980. 7. Lin G, Lunderquist A, Hagerstrand I: Umbilical and paraumbilical veins in ligamentum teres: Their significance as collaterals in portal hypertension. Acta Radio1 Diagnosis 25:l-5, 1984. 8. Lafortune M, Constantin A, Breton G, Legare AG, Lavoie P: The recanalized umbilical vein in portal hypertension: A myth. A J R 1441549-553,1985. 9. Dokmeci AK, Kimura K, Matsutani S, et al: Collateral veins in portal hypertension: Demonstration by sonography. A J R 137:1173-1177, 1981. 10. Saddekni S, Hutchinson DE, Cooperberg PL: The sonographically patent umbilical vein in portal hypertension. Radiology 145:441-443, 1982. 11. Itai Y, Ohtomo K, Kokubo T, Okada Y, Terano A. Portosystemic collaterals running through the medial segment of the liver connecting with the
paraumbilical vein in portal hypertension. Fortschr Rontgenstr 152:357-359, 1990. 12. Aagaard J, Jensen LI, Sorensen TIA, Christensen U, Burcharth F. Reeanalized umbilical vein in portal hypertension. A J R 139:1107-1109, 1982. 13. Ishikawa T, Tsukune Y, Ohyama Y, Fujikawa M, Sakuyama K, Fujii M: Venous abnormalities in portal hypertension demonstrated by CT. A J R 134~271-276,1980. 14. Weinreb JC, Hodges S, Garcia R: Magnetic resonance imaging of patent umbilical veins. A J R 144:747-748, 1985. 15. Gibson RN, Gibson PR, Donlan JD, Clunie DA: Identification of a patent paraumbilical vein by using Doppler sonography: Importance in the diagnosis of portal hypertension. A J R 153513-516, 1989. 16. Mostbeck GH, Wittich G, Herold C, Vergesslich KA, Walter RM, Frotz S, Sommer G Hemodynamic significance of the paraumbilical vein in portal hypertension: Assessment with duplex US. Radiology 170:339-342, 1989.
JOURNAL OF CLINICAL ULTRASOUND
Portosystemic Collateral Shunts Originating from the Left Portal Veins in Portal Hypertension: Demonstration by Color Doppler Flow Imaging Nobuyuki Sugiura, MD,* Eii Karasawa, MD,? Naoki Saotome, MD,? Makoto Miki, MD,? Shouichi Matsutani, MD,* Masao Ohto, MD*
Abstract: Color Doppler flow imaging was performed in 121 patients with portal hypertension. Portosystemic collateral shunts originating from the left portal veins were seen in 41 of the patients. A single collateral shunt was seen in 27 of these, and multiple collateral shunts were seen in the other 14. Collateral shunts running in the ligamentum teres were seen in 26 of the 41 patients; the veins ran through the liver parenchyma in 25 of these. B-mode ultrasound imaging could not clearly demonstrate vascular structures in 55% of the collateral shunts. Color Doppler flow imaging provided a clear picture of the course of the portosystemic collateral shunts originating from the left portal vein. 0 1992 John Wiley & Sons, Inc. Indexing Words: Portosystemic collateral shunts * Paraumbilical vein * Color Doppler flow imaging * Portal hypertension
Real-time B-mode ultrasound and pulsed Doppler ultrasound have been increasingly used as noninvasive procedures for examining the portal venous hemodynamics in portal hypertension.' Color Doppler flow imaging, which displays the blood flow in a color-coded manner, has also been applied to the abdomen, and its clinical potential has been discussed.2 Color Doppler flow imaging can demonstrate blood vessel patency and blood flow direction in a short time, and it can also detect a vessel not shown in B-mode ultrasound imaging by means of its color-coding feature. Color Doppler flow imaging has come to be considered very useful for the identification of vessels. Portosystemic collateral shunts originating from the left portal veins in portal hypertension have been investigated by various imaging mod a l i t i e ~ . ~There - ~ are, however, few reports on From the The First Department of Internal Medicine, Chiba University School of Medicine, Chiba, Japan, and The Department of Internal Medicine, Yokohama Higashi National Hospital, Kanagawa, Japan. For reprints contact Nobuyuki Sugiura, MD, The First Department of Internal Medicine, Chiba University School of Medicine, 1-8-1 Inohana, Chiba 260, Japan.
collateral shunts running through the liver parenchyma and draining into the paraumbilical veins in the falciform ligament. In this article, we report a color Doppler flow imaging investigation performed to demonstrate the portosystemic collateral shunts originating from the left portal veins in portal hypertension and the detectability of those in comparison with B-mode ultrasound imaging. MATERIALS AND METHODS
Color Doppler flow imaging was performed in 121 patients with liver cirrhosis and 3 with idiopathic portal hypertension during the period from April 1989 to January 1990 at the Yokohama Higashi National Hospital. This sample was comprised of 85 men and 36 women, with an age range of 37 to 79 years. Diagnosis was made based on histological findings only in 48 patients and on both clinical findings and imaging in the other 63. The equipment used was a SSA-270A scanner with a 3.75 MHz sector array probe and a 3.75 MHz convex array probe (Toshiba, Tokyo, Japan). All patients were first examined by B-mode ultrasound imaging, and then by color 427
SUGIURA ET AL.
428
compared with those demonstrated by B-mode ultrasound imaging.
TABLE 1 Courses of Portosystemic Collateral Shunts (PCS) Originating from the Left Portal Vein Course
No. of PCS
RESULTS
____
~
A
B
A+ B
(%)
(%1
(%)
No. of Patients
Single Multiple Two Three Four Mu.
27 14 8 3 1 2
14 (51.9) 2 (14.3) 0 0 0 2
13 (48.1) 2 (14.3) 2 0 0 0
Total
41
16 (39.0)
15 (36.6)
Portosystemic collateral shunts from the left portal veins were demonstrated in 41 (34%) of the 121 patients studied (Table 1). These collateral shunts showed a single course in 27 (66%)patients, and a multiple course in the remaining 14 (34%).Those with a single course were classified as course A in 14 (52%)of the 27 patients, and as course B in the remaining 13 patients (48%). Those having a multiple course were respectively classified as course A, B, or both in 2, 2, and 10 of the 14 patients, respectively. The routes numbered two in 8 patients, three in 3 patients, and 4 in l patient. The routes-showed a multiple tortuous tubular structure in the remaining 2 patients. Collateral shunts running in the ligamentum teres were seen in 26 of the 41 patients, and the veins ran through the liver parenchyma in 25 of these. The detectability of portosystemic collateral shunts originating from the left portal veins using B-mode ultrasound imaging was examined in the 39 patients that did not show a multiple tortuous tubular structure with color Doppler imaging (Table 2). An anechoic vascular structure in the ligamentum teres was clearly seen in 15 of the 24 collateral shunts classified as course A, but there was some difficulty with the visualization in the remaining 9 shunts. An anechoic vascular structure running between the umbilical portion of the left portal vein and the liver surface was seen in 14 of the 32 shunts classified as course B, but this was demonstrated in only a portion of the course in the remaining 18 shunts (Figure 2). B-mode ultrasound imaging could not clearly demonstrate vascular structures in 55% of the collateral shunts originating from the left portal veins.
10 (71.4) 6 3 1 0 10 (24.5)
MU.: multiple tortuous venous Structure.
Doppler flow imaging. The ultrasonographers were skilled with both ultrasound methods and were the same in both ultrasound imaging trials. Portosystemic collateral shunts originating from the left portal veins were classified into two types according to their course between the umbilical portion of the left portal veins and the anterior liver surface (Figure 1).
A. Course in or along the ligamentum teres. B. Course through the liver parenchyma. Vessels showing color-coded blood flows in either or both of these courses were regarded as portosystemic collateral shunts. On B-mode ultrasound imaging, tubular anechoic structures detected serially in the same sites were also regarded as collateral shunts. The time needed to detect these courses was either shorter in color Doppler flow imaging than in B-mode ultrasound imaging or was the same with both ultrasound methods. The features of portosystemic collateral shunts originating from the left portal veins were studied by color Doppler flow imaging, and
TABLE 2 Detectability of PCS with B-Mode Ultrasound Imaging PCS Course
A Single Multiple
B Single Multiple
No. of Veins
14 10
13 19
Demonstration of Vascular Structure Demonstrable
Unclear
Undernonstrable
(W
(%) 5 (35.7) 1 (10.0)
1 (7.1) 2 (20.0)
8 (61.5) 7 (70.0)
(YO)
Demonstrable
Demonstrable in part
% 6 (46.2) 8 (42.1)
7 (53.8) 11 (57.9)
%
JOURNAL OF CLINICAL ULTRASOUND
FIGURE 1. (b) Color Doppler image shows a red color-coded hepatofugal flow of PCS running in the ligamentum teres (course A).
-
Lig.Teres
FIGURE 1. Courses of portosysternic collateral shunts originating from the left portal veins (LPV). (a) The figure shows course A and 6. (A) Course in or along the ligamentum teres. (B)Course through the liver parenchyma.
FIGURE 1. (c) Color Doppler image shows an orange color-coded hepatofugal flow of PCS running through the liver parenchyma (course B). VOL. 20,
NO. 7, SEPTEMBER
1992
429
430
SUGIURA ET AL.
FIGURE 2. A case with PCS undemonstrated by 6-mode ultrasound imaging. (a) 6-mode image did not show a serial vascular structure between the left portal vein and the liver surface. (b) Color Doppler image shows a red color-coded flow between the left portal vein and the liver surface. JOURNAL OF CLINICAL ULTRASOUND
PORTOSYSTEMIC COLLATERAL SHUNTS
DISCUSSION Martin and Tudor' reported that paraumbilical veins were divided into three groups: Burrow's veins and Sappey's superior and inferior veins. Burrow's veins ascend from the epigastric veins along the umbilical vein and terminate independently in the middle third of the umbilical vein, failing to enter the portal system directly. Sappey's superior veins drain the median part of the diaphragm, traverse the upper part of the falciform ligament to reach the liver surface, and enter the sublobular divisions of the portal veins. Usually, paraumbilical veins that are discussed in portal hypertension correspond to those that were designated as Sappey's inferior veins. These veins communicate with epigastric and cutaneous veins, extend from the umbilical region to the liver, and have communications with the portal system in a variety of ways.7 Paraumbilical veins develop into collateral shunts originating from the left portal veins in portal hypertension. Other collateral shunts originating from the left portal veins appear as reopened umbilical veins. Until now, collateral shunts originating from the left portal veins were mostly designated as umbilical veins.4 Lin et al.7 studied whether collateral veins between the left portal veins and systemic veins in patients with portal hypertension actually represented reopened umbilical veins and paraumbilical veins; they reported that both served as part of a portosystemic collateral shunt in portal hypertension. On the other hand, Lafortune et a1.' reported, based on postmortem examinations, that such veins were all defined as paraumbilical veins around the umbilical vein. In imaging studies including ultrasound, it was impossible to determine whether a collateral vein in the ligamenturn teres was a paraumbilical vein or a reopened umbilical vein. We divided portosystemic collateral shunts originating from the left portal vein into two types according to their course: a course that ran in or along the ligamentum teres, and a course that ran through the liver parenchyma and the falciform ligament. Although portosystemic collateral shunts originating in the left portal vein running in the ligamentum teres observed by ultrasound or pulsed Doppler ultrasound have been studied exten~ i v e l y , ~the , ' ~ collateral veins running through the liver parenchyma have received little attention." This is because the vascular structure of the collateral vein running through the liver parenchyma is difficult to observe serially with VOL. 20, NO. 7, SEPTEMBER 1992
43 1
B-mode ultrasound imaging because it meanders beneath the liver surface. However, when an anechoic vascular structure on B-mode examination has a blood flow, it is easily visualized by its color-coded flow with color Doppler flow imaging. When a vessel with a color-coded flow is serially displayed from the umbilical portion of the left portal vein to the anterior liver surface, it is a portosystemic collateral shunt. In this study, the portosystemic collateral shunts running through the liver parenchyma were seen in 13 of 27 patients with a single collateral shunt and in 12 of 14 with multiple collateral shunts. Lafortune et a1.8 reported that paraumbilical veins found in patients with portal hypertension increased in number and diameter. We observed multiple-course paraumbilical veins in 34% of the 41 patients, and the maximum number of courses was four. To identify a portosystemic collateral shunt originating from the left portal vein, such invasive modalities as surgical portography, percutaneous transhepatic p~rtography,~ and arteriop ~ r t o g r a p h yas , ~ well as such noninvasive procedures as B-mode ultrasound imaging,5 X-ray computed tomography,13magnetic resonance imaging,14 and pulsed Doppler ultrasound,15 have been used to date. Pulsed Doppler ultrasound has been particularly useful in the examination of portal venous hemodynamics under physiological conditions.16 In the present study, B-mode ultrasound imaging was much less effective in detecting portosystemic collateral shunts originating from the left portal veins than we expected, but color Doppler flow imaging proved to be very practical for this purpose. The detection of transhepatic portosystemic collateral shunts in portal hypertension is difficult, and we must be careful with the evidence of transhepatic portosystemic collateral shunts, especially when they remain unidentified by B mode ultrasound.
REFERENCES Patriquin H, Lafortune M, Burns PN, Dauzat M: Duplex Doppler examination in portal hypertension: Technique and anatomy. AJR 149:71-76, 1987. Scoutt LM, Zawin ML, Taylor KJW: Doppler US. Part 11. Clinical applications. Radiology 174:309319, 1990. Hoevels J, Lunderquist A, Tylen US: Porto-systemic collaterals in cirrhosis of the liver. Actu Rudiol Diagnosis 20:865-877, 1979. Burchell AR, Panke WF, Moreno AH, Rousselot LM: The patent umbilical vein in portal hyperten-
432
SUGIURA ET AL.
sion. Surg Genecol Obstet 130:77-86, 1970. 5. Glazer GM, Laing FC, Brown TW, Gooding GAW: Sonographic demonstration of portal hypertension: The patent umbilical vein. Radiology 136:161-163, 1980. 6. Martin BF, Tudor RG. The umbilical and paraumbilical veins of man. J Anat 130:305-322, 1980. 7. Lin G, Lunderquist A, Hagerstrand I: Umbilical and paraumbilical veins in ligamentum teres: Their significance as collaterals in portal hypertension. Acta Radio1 Diagnosis 25:l-5, 1984. 8. Lafortune M, Constantin A, Breton G, Legare AG, Lavoie P: The recanalized umbilical vein in portal hypertension: A myth. A J R 1441549-553,1985. 9. Dokmeci AK, Kimura K, Matsutani S, et al: Collateral veins in portal hypertension: Demonstration by sonography. A J R 137:1173-1177, 1981. 10. Saddekni S, Hutchinson DE, Cooperberg PL: The sonographically patent umbilical vein in portal hypertension. Radiology 145:441-443, 1982. 11. Itai Y, Ohtomo K, Kokubo T, Okada Y, Terano A. Portosystemic collaterals running through the medial segment of the liver connecting with the
paraumbilical vein in portal hypertension. Fortschr Rontgenstr 152:357-359, 1990. 12. Aagaard J, Jensen LI, Sorensen TIA, Christensen U, Burcharth F. Reeanalized umbilical vein in portal hypertension. A J R 139:1107-1109, 1982. 13. Ishikawa T, Tsukune Y, Ohyama Y, Fujikawa M, Sakuyama K, Fujii M: Venous abnormalities in portal hypertension demonstrated by CT. A J R 134~271-276,1980. 14. Weinreb JC, Hodges S, Garcia R: Magnetic resonance imaging of patent umbilical veins. A J R 144:747-748, 1985. 15. Gibson RN, Gibson PR, Donlan JD, Clunie DA: Identification of a patent paraumbilical vein by using Doppler sonography: Importance in the diagnosis of portal hypertension. A J R 153513-516, 1989. 16. Mostbeck GH, Wittich G, Herold C, Vergesslich KA, Walter RM, Frotz S, Sommer G Hemodynamic significance of the paraumbilical vein in portal hypertension: Assessment with duplex US. Radiology 170:339-342, 1989.
JOURNAL OF CLINICAL ULTRASOUND
