Spleen - Accessory Spleen
comment:Accessory spleens ( Figure 1 , arrow) are rare findings in rodents and may be congenital, acquired following splenectomy, or a consequence of traumatic injury. When observed grossly in the peritoneal cavity, an accessory spleen may appear as one or more dark red to black nodules that have a smooth surface and range from less than a millimeter to several millimeters in diameter. These small nodules of splenic tissue have been observed in the mesenteric attachment of the spleen ( Figure 1 , arrowhead), pancreas, and elsewhere in the abdominal cavity. Histologically, accessory spleens may have all or some splenic components, such as the capsule, trabeculae, red pulp, and/or white pulp ( Figure 2 ).
recommendation:Accessory spleen should be diagnosed but not graded.
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Web page last updated on: January 27, 2015