Clin. Radiol. (1978) 29, 285-288

THE USE OF P R O S T A G L A N D I N F 2 - A L P H A IN S E L E C T I V E P A N C R E A T I C AND L E F T G A S T R I C A N G 1 O G R A P H Y

DAVID LEGGE

Department of Radiology, Mater Miserieordiae Hospital, Dublin

Prostaglandin F2-Alpha has been used in 10 superselective angiographic studies of the pancreas and 10 left gastric studies. Injection of Prostaglandin into the dorsal pancreatic or gastroduodenal artery increased opacification of small pancreatic vessels and better demon- strated the angiographic changes in three cases of carcinoma of the pancreas. Injection of the drug into the left gastric artery increased opacification of the left gastric vein, allowed identification of the direction of flow of the contrast medium and enhanced demonstration of gastro-oesophageal varices. It is concluded that Prostaglandin improves the quality of pancreatic and left gastric angiographic studies.

INTRODUCTION

Prostaglandin F2-Alpha is a potent vasodilator which enhances superior mesenteric, splenic and hepatic angiographic studies (Legge, 1977b). Recently we have injected this drug superselectively in an attempt to improve anatomic detail and diagnostic accuracy in cases investigated for suspected carcinoma of the pan- creas and portal hypertension. This paper describes the use of Pr0staglandin in pancreatic and left gastric angiography.

MATERIAL AND METHOD

Since August 1976 10 left gastric, six dorsal pan- creatic, and four gastroduodenal angiographic studies were performed before and after the intra-arterial injection of 60 gg of Prostaglandin F2-Alpha. In each instance 20 ml of Hypaque 65% were injected rapidly by hand. Ten patients were investigated for suspected carcinoma of the pancreas and 10 for suspected portal hypertension.

RESULTS

Pancreatic studies. Five of the patients investi- gated for carcinoma of the pancreas had normal angiographie studies, and subsequent investigations and clinical course gave no evidence for any pan- creatic lesion. One patient had primary carcinoma of the bile ducts and one hepatic metastases from carci- noma of the colon. The remaining three patients had carcinoma of the pancreas which resulted in encase- ment of pancreatic vessels.

Presented at the Annual General Meeting of the Royal College of Radiologists, June 1977.

Fig. 1 - Normal dorsal pancreatic study using Prostaglandin. The patient was a 64-year-old male with recent obstructive jaundice. There is intense filling of the small vessels in the head of the pancreas but no evidence for encasement. Carci- noma of the common bile duct was found at operation.

After the injection of Prostaglandin into the dorsal pancreatic or gastroduodenal artery, there was a measurable increase in the size of the vessels com- pared with the control studies and filling of many small arteries (Fig. 1). In each case the use of vaso- dilator opened collateral pathways, resulting in the passage of contrast medium into larger vessels, either the splenic, hepatic or superior mesenteric artery. Thus, in one case of carcinoma of the pancreas the injection into the dorsal pancreatic artery opacified the superior mesenteric artery which was shown to be occluded near its origin by the tumour (Fig. 2). In all three cases of carcinoma of the pancreas the vascular encasement was better demonstrated after Prosta- glandin (Fig. 2).

286 C L I N I C A L R A D I O L O G Y

Fig. 2 - Dorsal pancreatic angiogram of a 61-year-old patient with progressive abdominal pain and weight loss. Carcinoma of the pancreas was confirmed at operation. (a) Control study: there is some filling of pancreatic arcades. (b) After Prostaglandin injection: there is better demonstration of pancreatic arcades and filling of smaller vessels. Many arteries are irregular due to encasement by the carcinoma. Increased flow results in opacification of the superior mesenteric artery which is occluded near its origin (arrow).

Left gastric studies. - Of the 10 patients investi- gated for portal hypertension three had previously had a splenectomy. Five studies were normal and five gave evidence of gastro-oesophageal varices.

In each instance injection of Prostaglandin pro- duced a measurable increase in the size of the left

Fig. 3 - Normal left gastric angiogram of 20-year-old female investigated for suspected portal hypertension. The patient had previously had a splenectomy. (a) Control study: venous phase. Opacification of the left gastric vein is mediocre. (b) After Prostaglandin injection: demonstration of the left gastric vein is improved, and there is no evidence for varices. The portal vein is opacified (arrows) establishing that direc- tion of flow is towards the liver.

gastric artery and its branches compared with the control study. The venous opacification was improved, and in two cases the left gastric vein could not be identified without the use of the drug. In the five normal studies opacification after Prostaglandin was sufficient to demonstrate contrast medium draining into the portal vein, thus establishing that flow was towards the liver (Fig. 3). In the five studies of patients shown to have varices, opacification of the varices was improved. In four, serial films showed contrast in the dilated veins in the oesophagus, there- by establishing that flow was hepatofugal (Fig. 4). In the fifth the left gastric vein was shown to drain into the portal vein (Fig. 5). At operation portal vein pressure was normal, and the varices were due to localised occlusion of the splenic vein.

COMMENT

Prostaglandin F2-Alpha is a water-soluble fatty acid which has the property of relaxing vascular smooth muscle, resulting in vasodilatation. Unlike

SELECTIVE PANCREATIC AND LEFT GASTRIC A N G I O G R A P H Y 287

Fig. 4 -- Left gastric angiogram of a 22-year-old female who presented with haematemesis. Previous splenectomy had been performed. Superior mesenteric angiography demonstrated portal vein thrombosis. (a) Control study: venous phase. The left gastric vein and varices in the fundus of the stomach are demonstrated. (b) After Prostglandin injection: the left gastric vein and varices are better opacified. There is no con- trast medium within the portal vein. (c) Subsequent films of the series demonstrate flow of contrast medium into exten- sive varices within the oesophagus.

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other vasodilating drugs Prostaglandin F2-Alpha does no t impair the quali ty o f the arterial phase o f each study and does no t appear to produce any unwanted side effects (Dencker et al., 1975).

Inject ion o f the Prostaglandin into the dorsal pan- creatic or gast roduodenal artery resulted in increased opacif icat ion and distension of the smaller vessels in the pancreas. This increased distension o f pancreat ic arcades bet ter demons t ra ted the f ixed irregularities o f arteries encased by carcinoma. The pancreas is a highly vascular s t ructure and demons t ra t ion o f smaller arteries in the pancreas is essential for comple te angiographic evaluat ion. The improved f low

Fig. 5 - Left gastric study using Prostaglandin in a 38-year-old patient who had recurrent haematemesis. The veins in the stomach are dilated and tortuous, but the portal vein is opaci- fled (arrows) indicating that flow is towards the liver. At operation the portal vein pressure was found to be normal: the localised varices were due to splenic vein occlusion.

288 CLINICAL RADIOLOGY

obtained by the vasodilatation gave consistent opaci- fication of all the small vessels, and with such detailed studies exploratory surgery should be prevented when normal pancreatic vascularity is shown (Hawkins et al., 1975). If gastroduodenal or dorsal pancreatic injections fail to opacify the arteries in the tail of the pancreas, selective splenic angiography using Prosta- glandin will achieve this (Legge, 1977a).

Prostaglandin consistently improves opacification of the superior mesenteric splenic and portal veins and this is essential for the proper evaluation of portal hypertension (Legge, 1977b). However, selective left gastric angiography appears the most logical means o f demonstrating gastro-oesophageal varices since con- trast medium is injected into the vascular bed that drains directly to the varices. If splenectomy has been performed, as it had been in three patients in our series, left gastric studies may be the only means of diagnosing varices angiographically. The increased opacification of the venous drainage achieved by the

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injection of Prostaglandin into the left gastric artery improved the demonstration of any varices present and allowed identification of the direction of flow of contrast medium with good reliability in all our cases.

REFERENCES

Dencker, H., Gothlin, J., Hedner, P., Lunderquist, A., Norryd, C. & Tylen, U. (1975). Superior mesenteric angiography and blood flow following intra-arterial injection of Prostaglandin F2-Alpha. American Journal of Roentgen- ology, 125, 111-118.

Hawkins, Irvin F., Jr, Kaude, Juri, V. & MacGregor, Alexander (1975). Priscoline and Epinephrine in selective pancreatic angiography. Radiology, 116 (August), 311- 321.

Legge, D. A. (1977a). The use of Prostag~andin F2-Alpha in selective visceral angiography. British Journal of Radiology, 50, 251-255.

Legge, D. A. (1977b). The use of Prostaglandin F2-Alpha in selective hepatic angiography. Radiology, 124, 331-335.