Splenic Segments Research Articles

Venous segments in the goat (<i>Capra hircu</i><i>s</i>) spleen

46 goat spleens were studied to observe the venous segmentation in them by preparing the corrosion cast of the splenic vein and its intrasplenic tree. 56.5% of the specimens revealed the presence of two splenic venous segments - a right and a left one -, and 30.4% of cases showed the presence of three venous segments - a right, a left and a hilar one. The rest did not show any venous segmentations.

ANALYSIS OF VASCULAR RESPONSES IN THE SPLEEN.

Canine spleens were isolated and perfused at constant flow with blood from a femoral artery. Perfusion pressure, small vein pressure, tissue cannula pressure, organ weight, and capsular tension were monitored continuously. Splenic nerve stimulation and epinephrine elevated total resistance and increased small vein pressure more than tissue cannula pressure Evidence was provided which demonstrated that the venous pressure increment resulted primarily from active contraction of the splenic veins. Norepinephrine produced equivalent changes in total resistance but was significantly less effective than nerve stimulation and epinephrine, both in raising venous pressure and contracting the splenic capsule. Acetylcholine decreased total resistance, whereas venous pressure was increased by a passive mechanism. The effect of synthetic angiotensin was restricted to contraction of the splenic arterial segments. The highly distensible nature of the spleen was illustrated in experiments where total occlusion of venous flow had only minor effects upon the resistance to arterial inflow. Retrograde perfusion through the splenic vein failed to result in flow out of the splenic artery, indicating that valves or a valvelike mechanism are located at some presinusoidal site along the vascular tree.

Partial esophagogastrectomy in the treatment of esophagogastric varices.

THE INEVITABLE life-taking character of hemorrhage from esophagogastric varices still stands as a challenge. Some success and much failure have attended the numerous attempts that have been made in its management. 1 Present evidence suggests that some forms of portacaval shunt offers substantial palliation to patients with generalized portal hypertension. 2 Undoubtedly the rare patients with distal splenic vein obstruction respond well to simple splenectomy. Most difficult to manage are young persons without evidence of cirrhosis or of generalized portal hypertension who present varices and splenomegaly, many having undergone ineffectual splenectomy. Basic understanding concerning the latter patients has changed little since Professor Banti's original observations made nearly three quarters of a century ago. 3 Why should they early present morphologic evidence suggesting obstruction of only the splenic segment of the portal bed and yet later have definite cirrhosis manifest even by ascites? What effect might be obtained with early radical