# SPLENOMEGAL Y AND HYPERSPLENISM SPLENOMEGAL Y AND HYPERSPLENISM Splenomegaly is a common feature of many disease processes, although the spleen has to enlarge threefold before it is palpable ( Table 70.2 ). It should be borne in mind that many conditions a ff ecting the spleen, such as idiopathic thrombocytopenic purpura (ITP), may be associated with enlargement but the spleen is seldom palpable. Few conditions be that cause splenomegaly will require splenectomy as part of treatment. ). Hypersplenism is an indefinite clinical syndrome that is characterised by splenic enlargement, any combination of anaemia, leukopenia or thrombocytopenia, compensatory bone marrow hyperplasia and improvement after splenectomy . Careful clinical judgement is required to balance the long- and short-term risks of splenectomy against continued conserva - - tive management. computed tomography. Grade 1 Subcapsular haematoma <10% of surface area Parenchymal laceration <1 /uni00A0 cm depth Capsular tear Grade 2 Subcapsular haematoma 10–50% of surface area; intraparenchymal haematoma <5 /uni00A0 cm Parenchymal laceration 1–3 /uni00A0 cm Grade 3 Subcapsular haematoma >50% surface area; ruptured subcapsular or intraparenchymal haematoma ≥ 5 /uni00A0 cm Parenchymal laceration >3 /uni00A0 cm depth Grade 4 Any injury in the presence of a splenic vascular injury or active bleeding con /f_i ned within the splenic capsule Parenchymal laceration involving segmental or hilar vessels producing >25% devascularisation a Grade 5 Any injury in the presence of splenic vascular injury with active bleeding extending beyond the spleen into the peritoneum – shattered spleen a Vascular injury is de /f_i ned as a pseudoaneurysm or arteriovenous /f_i stula and appears as a focal collection of vascular contrast that decreases in attenuation with delayed imaging. Active bleeding from a vascular injury presents as vascular contrast, focal or diffuse, that increases in size or attenuation in the delayed phase.