CT angiography identifies collaterals in dogs with splenic vein obstruction and presumed regional splenic vein hypertension

Abstract

Occlusion of the splenic vein, without occlusion of the portal vein, can lead to a localized, regional splenic hypertension, referred as sinistral or left-sided portal hypertension in the human radiology literature. In people, may cause gastrointestinal hemorrhages from the esophageal and gastric varices and the primary pathology usually includes pancreatitis and pancreatic neoplasms. The final diagnosis of localized splenic hypertension necessitates accompanying normal liver functions and a patent extrahepatic portal vein. Following obstruction, the resultant elevated splenic bed venous pressure causes formation of collateral routes, the extent of which depends upon the level and degree of obstruction. In this retrospective descriptive study, authors assessed the collateral pathways in dogs with isolated splenic vein occlusion and possible regional splenic vein hypertension. Out of the 46 patients initially recruited, 25 were excluded due to the presence of concomitant portal thrombosis and direct/indirect CT signs of portal hypertension. The remaining 21 dogs had clinicopathological tests suggesting normal liver function. The causes of obstruction identified included splenic pedicle torsion, tumoral splenic vein invasion, and splenic vein thrombosis. Four of 21 dogs with isolated splenic vein obstruction showed collateral pathways through the left gastroepiploic vein (4/4), left gastric vein (2/4), and splenogonadal vein (1/4). The diagnosis of isolated, regional splenic hypertension should be based on clinical, biochemical, and radiological evaluation. Computed tomography is an excellent tool to assess the collateral patterns and to determine the underlying cause.

Ultrasonographic and CT diagnosis of a complete splenic duplication with right splenic torsion and presumed regional splenic vein hypertension in a dog

“…This case report highlights the important roles of CT and ultrasound as complementary modalities for the clinical management of a dog with a splenic duplication, torsion of the right‐sided viscus and clinical signs presumably related to regional splenic vein hypertension. Recently, an original investigation about canine presumed regional splenic vein hypertension was published, although without focusing on the gastrointestinal disorders or evidence of splenic duplication 3 . Viscera duplications have been widely described in veterinary medicine, affecting primarily the gastrointestinal and urogenital tract.…”

“…Splenic vein occlusion results in back pressure, which is transmitted to the left side of the portal system through the anastomoses between the splenic vein and the gastroepiploic vein. This reversal of flow may result in hypertension with secondary gastric/gastroesophageal varices (GVs), considered major sources for the gastrointestinal bleeding in regional splenic vein hypertension 3,11,12 . Furthermore, this syndrome is often associated with splenomegaly and normal liver function, with presence of GVs only in 35–45% of the cases 11 .…”

“…Recently, an original investigation about canine presumed regional splenic vein hypertension was published, although without focusing on the gastrointestinal disorders or evidence of splenic duplication. 3 Viscera duplications have been widely described in veterinary medicine, affecting primarily the gastrointestinal and urogenital tract. The clinical signs often include abdominal discomfort or urinary incontinence.…”

“…This reversal of flow may result in hypertension with secondary g astric/gastroesophageal varices (GVs), considered major sources for the gastrointestinal bleeding in regional splenic vein hypertension. 3 , 11 , 12 Furthermore, this syndrome is often associated with splenomegaly and normal liver function, with presence of GVs only in 35–45% of the cases. 11 Splenectomy attenuates the arterial inflow into the left portal system and results in decompression of the concurrent gastric varices.…”

The clinical applicability of percutaneous splenic vein stent implantation for pancreatic portal hypertension

“…Computed tomography (CT) is an excellent tool to assess the collateral patterns and to determine the underlying cause [ 7 ]. So all the patients underwent evaluation of the pancreas, liver, and portal vein system through contrast-enhanced abdominal CT (Fig.…”