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Hemodynamics of splenic artery aneurysm
GASTROENTEROLOGY 1986:90:1042-6
Hemodynamics Aneurysm
of Splenic Artery
OSAMU NISHIDA, FUMINORI MORIYASU, TAKEFUMI NAKAMURA, NOBUYUKI BAN, KENSUKE MIURA, MASAHIKO SAKAI, HARUTO UCHINO, and TAKE0 MIYAKE First Department of Internal Medicine and Department of Geriatrics, Faculty of Medicine, Kyoto University, Kyoto, Japan
Blood flow volume of the portal venous system of 3 patients with splenic artery aneurysm, an uncommon disease, was measured using an ultrasonic duplex system. A huge increase in splenic blood flow volume was found in each case. A large portasystemic shunt through which the portal blood flowed hepatofugally was present in 2 cases. We for an suspect the shunt is partially responsible increase
in splenic
blood flow volume,
lead to the formation of splenic together with portal hypertension.
which
artery
would
aneurysm
Aneurysms of the splenic artery are considered to be relatively uncommon. It is said that there is an association between splenic artery aneurysms and portal hypertension (1,~). Moreover, there are many reports suggesting that there is a relationship between the formation of splenic artery aneurysms and increases in splenic blood flow (3). However, there have been no reports in which the increases in splenic blood flow have been detailed. This paper describes 3 cases involving aneurysm of the splenic artery. Portal hypertension was present in 2 cases, but not in the third. In all cases, the splenic venous blood flow volume was measured using an ultrasonic duplex system (4) composed of a linear electronic scanner and a pulsed Doppler beam. Case Reports Case 1 A 62-yr-old obese woman was admitted to Kyoto 1984. Examination University Hospital in February Received April 1, 1985. Accepted October 1, 1985. Address requests for reprints to: F. Moriyasu, M.D., The First Department of Internal Medicine, Faculty of Medicine, Kyoto University, 54 Shogoin-Kawaramachi, Sakyo-ku, Kyoto 606, Japan. 0 1986 by the American Gastroenterological Association 0016-5085/86/$3.50
showed her to be jaundiced and to have hepatosplenomegaly. She had complained of general fatigue in July 1983. In January 1984 she consulted a doctor and was diagnosed as suffering from liver cirrhosis with splenomegaly. She had had 4 children. Laboratory studies disclosed the following values: red blood cell count, 3.07 million/mm3; platelet count, 41,000/mm3; white blood cell count, 1300/mm3; serum albumin, 2.6 gidl; serum bilirubin, 4.3 mg/dl; prothrombin time, 15.5 s; and partial thromboplastin time, 61.7 s. We suspected that the patient had liver cirrhosis with portal hypertension. Angiography was performed (Figure 1). There was a large splenic artery aneurysm (diameter, 3.5 cm) at the hilus of the spleen and a large left gastric vein through which the blood flowed hepatofugally. Portal venous pressure was 21 mmHg, measured using a percutaneous transhepatic portal catheter.
Case 2 A 58-yr-old woman was admitted to Kyoto University Hospital in February 1984. Examination showed her to have splenomegaly. In September 1983 she had been operated on for uterine cancer and at that time she was found to be suffering from pancytopenia. She had had 3 children. Laboratory studies disclosed the following values: red blood cell count, 3.97 million/mm3; platelet count, 74,000/mm3; white blood cell count, 2200/mm3; serum albumin, 4.2 g/dl; serum bilirubin, 0.7 mg/dl; prothrombin time, 12.5 s; and partial thromboplastin time, 40.8 s. Radiologic studies showed an oval calcified shadow in the left upper quadrant of the abdomen. We suspected that the patient was suffering from idiopathic portal hypertension with splenic artery aneurysm. Angiography was performed (Figure 2). There was a splenic artery aneurysm [diameter, 3.0 cm) with calcification and a large splenorenal shunt at the hilus of the spleen. There was no sign of corkscrewing in the hepatic artery, corkscrewing being a typical sign of liver cirrhosis. Portal venous pressure was 18 mmHg, measured using a percutaneous transhepatic portal catheter.
April
1986
Figure
1. A large splenic artery aneurysm in the hilus of the spleen hepatofugally in the venous phase (right] are shown.
Figure
2. A splenic artery aneurysm percutaneous transhepatic
in the hilus of the spleen portography (right).
(left) and
(left) and
a large
a splenorenal
left gastric
shunt
vein
are shown
in which
in this
the blood
photograph
flows
of tht
1044
GASTROENTEROLOGY
NISHIDA ET AL.
Vol. 90. No. 4
Case 3 A 39-yr-old woman was admitted to Kyoto University Hospital in July 1984. Examination showed her general condition to be average. In June 1984 she had consulted a doctor because of common cold symptoms. She was found at that time to have leukopenia, and further examination showed her to have both a hepatic tumor and a gastric submucosal tumor. She had had 3 children. Laboratory studies disclosed the following values: red blood cell count, 4.02 million/mm3; platelet count, 232,000/mm3; white blood cell count, 3000/mm3; and liver function, normal. Ultrasonography showed that the hepatic tumor was a hemangioma. Angiography was performed (Figure 3) and the diagnosis was confirmed. It was also found that the patient had a splenic artery aneurysm (diameter, 2.5 cm) that was diagnosed as a gastric submucosal tumor by endoscopy. Portal venous pressure was 8 mmHg, measured using a percutaneous transhepatic portal catheter. Venous Blood Flow Measurement
Figure 3. A splenic artery aneurysm is shown, but there is no abnormality in the portography (right).
An ultrasonic duplex system composed of a lineararray type electronic scanner and a pulsed Doppler flowmeter [TOSHIBA SAL 5OAISDL OlA system) was used in this hemodynamic study (Figure 4). The cross-sectional image of the vessel was displayed along its longitudinal axis using the B mode, and the sample position for the Doppler mode was set at the central portion of the vessel. Maximum velocity (Vo ,,,) in
Figure 4. Measurement of the blood flow volume using the ultrasonic duplex system.
4pril
HEMODYNAMICS
1986
Table
1. Blood Flow Volume”
Case 1 Case 2 Case 3
PV
SPV
SMV
323 1301 1771
2783 710 849
595 591 692
vein; SMV, superior mesenteric vein: SPV, splenic vein. ” Values are given in milliliters per minute. PV, portal
the central axis of the blood vessel was measured from the Doppler spectrum obtained. The angle (0) that was created between the ultrasonic Doppler beam and the blood vessel was obtained from the B-mode image. Immediately after recording the Doppler signals, the vessel at the sample position was scanned on the cross section, orthogonal to its longitudinal axis, and the cross-sectional area (S) was measured on the B-mode image display. The blood flow volume of the vessel (BFV) was calculated using the following equation: BFV = S x
0.57Voln,x
case
x 60
(mlimin).
The coefficient 0.57 was obtained from the original iment using bovine blood and a silicone tube (5).
exper-
Hemodynamics The values of the blood flow volume in various vessels were combined in each of the 3 cases (Table 1).The splenic venous blood flow volume was 2783 mlimin in case 1, 710 mlimin in case 2, and 849 mlimin in case 3. Portal venous pressures were 21, 18, and 8 mmHg, respectively. Portal hypertension was diagnosed in the first 2 cases. Our previous report concerning the blood flow volumes of the portal, splenic, and superior mesenteric veins indicated an increase in splenic venous blood flow volume in patients with liver cirrhosis (Table 2). However, the splenit venous blood flow volumes in these 3 patients were higher than average for patients with liver cirrhosis (5) (Table 2). Moreover, the value indicated for case 2 is derived from the blood flow volume only through the splenic vein and does not take into account the flow volume through the large splenorenal shunt in the hilus of the spleen, through which the splenic blood flowed hepatofugally. Therefore, we suspect that, in this case, the total splenic blood flow was actually higher than is indicated in the table.
ARTERY
ANEIJRYSM
1045
and of Fast Fourier Transform in the analysis of the Doppler signals, it has been possible to display both the B mode and the Doppler mode at the same time and in real time. As for the vessels of the portal venous system, pulsatile changes are rare in flow velocity, which is comparatively low, and the crosssectional areas are large enough to be measured using the B-mode scanner. Therefore. the blood flow volume of these vessels has, compared with the heart or arteries, many favorable aspects for quantitative measurement using a combined pulsed Doppler flowmeter and B-mode scanner. There are many reports concerning the splenic artery aneurysm. Stanley et al. (3) studied 60 cases with splenic artery aneurysm and classified them into five types according to the cause that promoted the formation of the splenic artery aneurysm: group I, associated with arterial dysplasia (13%); group 2, associated with portal hypertension with splenomegaly (10%); group 3. associated with focal arterial inflammatory process (5%); group 4, associated with hormonal and hemodynamic events in parous women (58%); and group 5, without clearly recognizable pathogenic factors although arteriosclerosis was suspected (13%). Many reports (8,9) in the West concern group 4. However, in Japan, Kita et al. (10) reported 37 of 71 (52.1%) cases with splenic artery aneurysm due to portal hypertension, and Kameyama et al. (11) reported 23 of 53 (45%) cases with splenic artery aneurysm due to portal hypertension. Furthermore, we know that portal hypertension is usually associated with the circulatory hyperdynamics in
the spleen (12). Therefore, in Japan, it is said that most splenic artery aneurysms are caused by portal hypertension. Joske (1) reported on 2 cases and mentioned that there were two factors related to the development of large proximal splenic artery aneurysms in female patients with chronic liver disease. One is the inTable
2. Portal Blood Flow Volume and Splenic Blood Flow Volume
Discussion The ultrasonic Doppler method has been widely used in clinical practice as a noninvasive blood flowmeter (6,7). Use of a combined B-mode and pulsed Doppler method, in which frequency analysis is performed using the time gating technique, has allowed us to obtain information about the blood flow in arbitrary deep-seated blood vessels. Furthermore, by making use of electronic scanning for B-mode tomography
OF SPLENIC
Normal subjects Chronic
active
hepatitis Cirrhosis Idiopathic
portal
hypertension Hepatoma Values
are mean
normal
subjects.
Venous
No. of cases
Portal blood flow volumcx (ml.‘min)
Splenic venous blood flo\\ volume (mUmin)
88 45
889 -t 284 853 t 223
450 t 192 504 ? 147
81 16
881 t 331 979 r 411
690 r 465” 977 i- 538”
39
922 k 409
587 -t 301”
-C SD. ” p c 0.05.
I) 11 ,: 0.001
compared
with
1046
GASTROENTEROLOGY Vol. 90. No. 4
NISHIDA ET AL.
creased splenic blood flow and hypertension of portal system, and the other is the endocrine changes of pregnancy. Cobos et al. (13) gave four reasons for the preferential development of the splenic artery aneurysm in women. Included in these four reasons were excessive splenic arteriovenous shunting during pregnancy, particularly when the spleen is enlarged, and mechanical stress on the wall of the tortuous and long splenic artery due to increased blood flow during pregnancy. As can be seen, there are many reports that indicate a relationship between the increase in splenic blood flow and the formation of splenic artery aneurysm. We, however, could not find any report in which measurement of the splenic blood flow volume was detailed. Puttini et al. (2) performed celiac angiography in 170 patients with liver cirrhosis and found 15 cases with splenic artery aneurysm. They found a positive relationship between the size of the aneurysm and the diameter of the splenic artery, and showed indirectly that a positive relationship existed between the aneurysm and the splenic blood flow volume. We measured the blood flow volume in the 3 cases in this report and detected an increase in splenic blood flow volume in each case. As the first report that gives such details, we think this paper is of importance. Gonzalez et al. (14) reported an interesting case of splenic artery aneurysm. The aneurysm in this case was discovered by angiography 3 mo after a distal splenorenal shunt operation. It continued to increase in size during the succeeding 3 wk. The patient later underwent splenectomy. They suggested that the enlargement of the splenic artery aneurysm was due to a progressive increase in splenic blood’flow due to the presence of the splenorenal shunt. Large spontaneous portasystemic shunts were detected in 2 of the 3 cases described in this report. One such shunt was through the greatly enlarged left gastric vein (case l),whereas the other was splenorenal (case 2). We therefore suspect that the formation of large portasystemic shunts, which reduce the
blood flow resistance of the portal outflow tract and induce an increase in the portal blood inflow volume, promote the formation of splenic artery aneurysm together with the portal hypertension.
References 1. Joske RA. Occurrence 2.
3. 4.
5.
6.
of large proximal splenic aneurysms in chronic liver disease. Aust NZ J Med 1978;8:515-7. Puttini M, Aseni P, Branbilla G, et al. Splenic artery aneurysms in portal hypertension. J Cardiqvasc Surg (Torino) 1982;23:490-3. Stanley JC, Fry WJ. Pathogenesis and clinical significance of splenic artery aneurysms. Surgery 1974;76:898-909. Moriyasu F, Ban N, Nishida 0, et al. Quantitative measurement of portal blood flow in patients with chronic liver disease using an ultrasonic duplex system consisting of a pulsed Doppler flowmeter and B-mode electroscanner. Gastroenterol Jpn 1984;19:529-36. Moriyasu F, Nishida 0, Ban N, et al. Quantitative measurement of the portal blood flow in patients with various liver diseases using an ultrasonic duplex system. Acta Hepatorogica Jpn 1985;26:208-14. Benchimol A, Desser KB, Gartlan JL. Bidirectional blood flow velocity in the cardiac chambers and great vessels studied with the Doppler ultrasonic flowmeter. Am J Med 1972;
52:467-73. 7. Nimura Y, Matsuo H, Hayashi T, et al. Studies on arterial flow
8.
9. 10.
11. 12.
13.
14.
patterns-instantaneous velocity spectrums and their phasic changes-with directional ultrasonic Doppler technique. Br Heart J 1974;36:899-907. Mehrotra D, diBenedetto R, Theriot E, et al. Spontaneous rupture of splenic artery aneurysm: sixth instance of both maternal and fetal survival. Obstet Gynecol 1983;62:665-6. O’Grandy JP, Day EJ, Toole FAL, et al. Splenic artery aneurysm rupture in pregnancy. Obstet Gynecol 1977;50:627-30. Kita R, Sakamoto K, Yoden Y, et al. A case with splenic artery aneurysm which was diagnosed as a submucosal tumor in the stomach. Surg Ther 1983;25:736-9 [in Japanese). Kameyama M, Okamoto N, Doi 0, et al. A case with splenic artery aneurysm. Cei Surg 1983;38:389-92 (in Japanese). Witte CL, Witte MH, Renert W, et al. Splenic circulatory dynamics in congestive splenomegaly. Gastroenterology 1974;67:498-505. Cobos JM, Hisano K, Matsumori M, et al. Multiple calcified aneurysms of splenic artery, hypersplenism and concomitant cholelithiasis. Jpn J Surg 1982;12:448-52. Gonzalez EM, Blanch GG, Blanc0 JMS, et al. Treatment of splenic artery aneurysm after distal splenorenal shunt. A case report. Jpn J Surg 1981;11:377-80.
Hemodynamics Aneurysm
of Splenic Artery
OSAMU NISHIDA, FUMINORI MORIYASU, TAKEFUMI NAKAMURA, NOBUYUKI BAN, KENSUKE MIURA, MASAHIKO SAKAI, HARUTO UCHINO, and TAKE0 MIYAKE First Department of Internal Medicine and Department of Geriatrics, Faculty of Medicine, Kyoto University, Kyoto, Japan
Blood flow volume of the portal venous system of 3 patients with splenic artery aneurysm, an uncommon disease, was measured using an ultrasonic duplex system. A huge increase in splenic blood flow volume was found in each case. A large portasystemic shunt through which the portal blood flowed hepatofugally was present in 2 cases. We for an suspect the shunt is partially responsible increase
in splenic
blood flow volume,
lead to the formation of splenic together with portal hypertension.
which
artery
would
aneurysm
Aneurysms of the splenic artery are considered to be relatively uncommon. It is said that there is an association between splenic artery aneurysms and portal hypertension (1,~). Moreover, there are many reports suggesting that there is a relationship between the formation of splenic artery aneurysms and increases in splenic blood flow (3). However, there have been no reports in which the increases in splenic blood flow have been detailed. This paper describes 3 cases involving aneurysm of the splenic artery. Portal hypertension was present in 2 cases, but not in the third. In all cases, the splenic venous blood flow volume was measured using an ultrasonic duplex system (4) composed of a linear electronic scanner and a pulsed Doppler beam. Case Reports Case 1 A 62-yr-old obese woman was admitted to Kyoto 1984. Examination University Hospital in February Received April 1, 1985. Accepted October 1, 1985. Address requests for reprints to: F. Moriyasu, M.D., The First Department of Internal Medicine, Faculty of Medicine, Kyoto University, 54 Shogoin-Kawaramachi, Sakyo-ku, Kyoto 606, Japan. 0 1986 by the American Gastroenterological Association 0016-5085/86/$3.50
showed her to be jaundiced and to have hepatosplenomegaly. She had complained of general fatigue in July 1983. In January 1984 she consulted a doctor and was diagnosed as suffering from liver cirrhosis with splenomegaly. She had had 4 children. Laboratory studies disclosed the following values: red blood cell count, 3.07 million/mm3; platelet count, 41,000/mm3; white blood cell count, 1300/mm3; serum albumin, 2.6 gidl; serum bilirubin, 4.3 mg/dl; prothrombin time, 15.5 s; and partial thromboplastin time, 61.7 s. We suspected that the patient had liver cirrhosis with portal hypertension. Angiography was performed (Figure 1). There was a large splenic artery aneurysm (diameter, 3.5 cm) at the hilus of the spleen and a large left gastric vein through which the blood flowed hepatofugally. Portal venous pressure was 21 mmHg, measured using a percutaneous transhepatic portal catheter.
Case 2 A 58-yr-old woman was admitted to Kyoto University Hospital in February 1984. Examination showed her to have splenomegaly. In September 1983 she had been operated on for uterine cancer and at that time she was found to be suffering from pancytopenia. She had had 3 children. Laboratory studies disclosed the following values: red blood cell count, 3.97 million/mm3; platelet count, 74,000/mm3; white blood cell count, 2200/mm3; serum albumin, 4.2 g/dl; serum bilirubin, 0.7 mg/dl; prothrombin time, 12.5 s; and partial thromboplastin time, 40.8 s. Radiologic studies showed an oval calcified shadow in the left upper quadrant of the abdomen. We suspected that the patient was suffering from idiopathic portal hypertension with splenic artery aneurysm. Angiography was performed (Figure 2). There was a splenic artery aneurysm [diameter, 3.0 cm) with calcification and a large splenorenal shunt at the hilus of the spleen. There was no sign of corkscrewing in the hepatic artery, corkscrewing being a typical sign of liver cirrhosis. Portal venous pressure was 18 mmHg, measured using a percutaneous transhepatic portal catheter.
April
1986
Figure
1. A large splenic artery aneurysm in the hilus of the spleen hepatofugally in the venous phase (right] are shown.
Figure
2. A splenic artery aneurysm percutaneous transhepatic
in the hilus of the spleen portography (right).
(left) and
(left) and
a large
a splenorenal
left gastric
shunt
vein
are shown
in which
in this
the blood
photograph
flows
of tht
1044
GASTROENTEROLOGY
NISHIDA ET AL.
Vol. 90. No. 4
Case 3 A 39-yr-old woman was admitted to Kyoto University Hospital in July 1984. Examination showed her general condition to be average. In June 1984 she had consulted a doctor because of common cold symptoms. She was found at that time to have leukopenia, and further examination showed her to have both a hepatic tumor and a gastric submucosal tumor. She had had 3 children. Laboratory studies disclosed the following values: red blood cell count, 4.02 million/mm3; platelet count, 232,000/mm3; white blood cell count, 3000/mm3; and liver function, normal. Ultrasonography showed that the hepatic tumor was a hemangioma. Angiography was performed (Figure 3) and the diagnosis was confirmed. It was also found that the patient had a splenic artery aneurysm (diameter, 2.5 cm) that was diagnosed as a gastric submucosal tumor by endoscopy. Portal venous pressure was 8 mmHg, measured using a percutaneous transhepatic portal catheter. Venous Blood Flow Measurement
Figure 3. A splenic artery aneurysm is shown, but there is no abnormality in the portography (right).
An ultrasonic duplex system composed of a lineararray type electronic scanner and a pulsed Doppler flowmeter [TOSHIBA SAL 5OAISDL OlA system) was used in this hemodynamic study (Figure 4). The cross-sectional image of the vessel was displayed along its longitudinal axis using the B mode, and the sample position for the Doppler mode was set at the central portion of the vessel. Maximum velocity (Vo ,,,) in
Figure 4. Measurement of the blood flow volume using the ultrasonic duplex system.
4pril
HEMODYNAMICS
1986
Table
1. Blood Flow Volume”
Case 1 Case 2 Case 3
PV
SPV
SMV
323 1301 1771
2783 710 849
595 591 692
vein; SMV, superior mesenteric vein: SPV, splenic vein. ” Values are given in milliliters per minute. PV, portal
the central axis of the blood vessel was measured from the Doppler spectrum obtained. The angle (0) that was created between the ultrasonic Doppler beam and the blood vessel was obtained from the B-mode image. Immediately after recording the Doppler signals, the vessel at the sample position was scanned on the cross section, orthogonal to its longitudinal axis, and the cross-sectional area (S) was measured on the B-mode image display. The blood flow volume of the vessel (BFV) was calculated using the following equation: BFV = S x
0.57Voln,x
case
x 60
(mlimin).
The coefficient 0.57 was obtained from the original iment using bovine blood and a silicone tube (5).
exper-
Hemodynamics The values of the blood flow volume in various vessels were combined in each of the 3 cases (Table 1).The splenic venous blood flow volume was 2783 mlimin in case 1, 710 mlimin in case 2, and 849 mlimin in case 3. Portal venous pressures were 21, 18, and 8 mmHg, respectively. Portal hypertension was diagnosed in the first 2 cases. Our previous report concerning the blood flow volumes of the portal, splenic, and superior mesenteric veins indicated an increase in splenic venous blood flow volume in patients with liver cirrhosis (Table 2). However, the splenit venous blood flow volumes in these 3 patients were higher than average for patients with liver cirrhosis (5) (Table 2). Moreover, the value indicated for case 2 is derived from the blood flow volume only through the splenic vein and does not take into account the flow volume through the large splenorenal shunt in the hilus of the spleen, through which the splenic blood flowed hepatofugally. Therefore, we suspect that, in this case, the total splenic blood flow was actually higher than is indicated in the table.
ARTERY
ANEIJRYSM
1045
and of Fast Fourier Transform in the analysis of the Doppler signals, it has been possible to display both the B mode and the Doppler mode at the same time and in real time. As for the vessels of the portal venous system, pulsatile changes are rare in flow velocity, which is comparatively low, and the crosssectional areas are large enough to be measured using the B-mode scanner. Therefore. the blood flow volume of these vessels has, compared with the heart or arteries, many favorable aspects for quantitative measurement using a combined pulsed Doppler flowmeter and B-mode scanner. There are many reports concerning the splenic artery aneurysm. Stanley et al. (3) studied 60 cases with splenic artery aneurysm and classified them into five types according to the cause that promoted the formation of the splenic artery aneurysm: group I, associated with arterial dysplasia (13%); group 2, associated with portal hypertension with splenomegaly (10%); group 3. associated with focal arterial inflammatory process (5%); group 4, associated with hormonal and hemodynamic events in parous women (58%); and group 5, without clearly recognizable pathogenic factors although arteriosclerosis was suspected (13%). Many reports (8,9) in the West concern group 4. However, in Japan, Kita et al. (10) reported 37 of 71 (52.1%) cases with splenic artery aneurysm due to portal hypertension, and Kameyama et al. (11) reported 23 of 53 (45%) cases with splenic artery aneurysm due to portal hypertension. Furthermore, we know that portal hypertension is usually associated with the circulatory hyperdynamics in
the spleen (12). Therefore, in Japan, it is said that most splenic artery aneurysms are caused by portal hypertension. Joske (1) reported on 2 cases and mentioned that there were two factors related to the development of large proximal splenic artery aneurysms in female patients with chronic liver disease. One is the inTable
2. Portal Blood Flow Volume and Splenic Blood Flow Volume
Discussion The ultrasonic Doppler method has been widely used in clinical practice as a noninvasive blood flowmeter (6,7). Use of a combined B-mode and pulsed Doppler method, in which frequency analysis is performed using the time gating technique, has allowed us to obtain information about the blood flow in arbitrary deep-seated blood vessels. Furthermore, by making use of electronic scanning for B-mode tomography
OF SPLENIC
Normal subjects Chronic
active
hepatitis Cirrhosis Idiopathic
portal
hypertension Hepatoma Values
are mean
normal
subjects.
Venous
No. of cases
Portal blood flow volumcx (ml.‘min)
Splenic venous blood flo\\ volume (mUmin)
88 45
889 -t 284 853 t 223
450 t 192 504 ? 147
81 16
881 t 331 979 r 411
690 r 465” 977 i- 538”
39
922 k 409
587 -t 301”
-C SD. ” p c 0.05.
I) 11 ,: 0.001
compared
with
1046
GASTROENTEROLOGY Vol. 90. No. 4
NISHIDA ET AL.
creased splenic blood flow and hypertension of portal system, and the other is the endocrine changes of pregnancy. Cobos et al. (13) gave four reasons for the preferential development of the splenic artery aneurysm in women. Included in these four reasons were excessive splenic arteriovenous shunting during pregnancy, particularly when the spleen is enlarged, and mechanical stress on the wall of the tortuous and long splenic artery due to increased blood flow during pregnancy. As can be seen, there are many reports that indicate a relationship between the increase in splenic blood flow and the formation of splenic artery aneurysm. We, however, could not find any report in which measurement of the splenic blood flow volume was detailed. Puttini et al. (2) performed celiac angiography in 170 patients with liver cirrhosis and found 15 cases with splenic artery aneurysm. They found a positive relationship between the size of the aneurysm and the diameter of the splenic artery, and showed indirectly that a positive relationship existed between the aneurysm and the splenic blood flow volume. We measured the blood flow volume in the 3 cases in this report and detected an increase in splenic blood flow volume in each case. As the first report that gives such details, we think this paper is of importance. Gonzalez et al. (14) reported an interesting case of splenic artery aneurysm. The aneurysm in this case was discovered by angiography 3 mo after a distal splenorenal shunt operation. It continued to increase in size during the succeeding 3 wk. The patient later underwent splenectomy. They suggested that the enlargement of the splenic artery aneurysm was due to a progressive increase in splenic blood’flow due to the presence of the splenorenal shunt. Large spontaneous portasystemic shunts were detected in 2 of the 3 cases described in this report. One such shunt was through the greatly enlarged left gastric vein (case l),whereas the other was splenorenal (case 2). We therefore suspect that the formation of large portasystemic shunts, which reduce the
blood flow resistance of the portal outflow tract and induce an increase in the portal blood inflow volume, promote the formation of splenic artery aneurysm together with the portal hypertension.
References 1. Joske RA. Occurrence 2.
3. 4.
5.
6.
of large proximal splenic aneurysms in chronic liver disease. Aust NZ J Med 1978;8:515-7. Puttini M, Aseni P, Branbilla G, et al. Splenic artery aneurysms in portal hypertension. J Cardiqvasc Surg (Torino) 1982;23:490-3. Stanley JC, Fry WJ. Pathogenesis and clinical significance of splenic artery aneurysms. Surgery 1974;76:898-909. Moriyasu F, Ban N, Nishida 0, et al. Quantitative measurement of portal blood flow in patients with chronic liver disease using an ultrasonic duplex system consisting of a pulsed Doppler flowmeter and B-mode electroscanner. Gastroenterol Jpn 1984;19:529-36. Moriyasu F, Nishida 0, Ban N, et al. Quantitative measurement of the portal blood flow in patients with various liver diseases using an ultrasonic duplex system. Acta Hepatorogica Jpn 1985;26:208-14. Benchimol A, Desser KB, Gartlan JL. Bidirectional blood flow velocity in the cardiac chambers and great vessels studied with the Doppler ultrasonic flowmeter. Am J Med 1972;
52:467-73. 7. Nimura Y, Matsuo H, Hayashi T, et al. Studies on arterial flow
8.
9. 10.
11. 12.
13.
14.
patterns-instantaneous velocity spectrums and their phasic changes-with directional ultrasonic Doppler technique. Br Heart J 1974;36:899-907. Mehrotra D, diBenedetto R, Theriot E, et al. Spontaneous rupture of splenic artery aneurysm: sixth instance of both maternal and fetal survival. Obstet Gynecol 1983;62:665-6. O’Grandy JP, Day EJ, Toole FAL, et al. Splenic artery aneurysm rupture in pregnancy. Obstet Gynecol 1977;50:627-30. Kita R, Sakamoto K, Yoden Y, et al. A case with splenic artery aneurysm which was diagnosed as a submucosal tumor in the stomach. Surg Ther 1983;25:736-9 [in Japanese). Kameyama M, Okamoto N, Doi 0, et al. A case with splenic artery aneurysm. Cei Surg 1983;38:389-92 (in Japanese). Witte CL, Witte MH, Renert W, et al. Splenic circulatory dynamics in congestive splenomegaly. Gastroenterology 1974;67:498-505. Cobos JM, Hisano K, Matsumori M, et al. Multiple calcified aneurysms of splenic artery, hypersplenism and concomitant cholelithiasis. Jpn J Surg 1982;12:448-52. Gonzalez EM, Blanch GG, Blanc0 JMS, et al. Treatment of splenic artery aneurysm after distal splenorenal shunt. A case report. Jpn J Surg 1981;11:377-80.