Diameter of splenic vein is a risk factor for portal or splenic vein thrombosis after laparoscopic splenectomy

Background. Splenomegaly is a risk factor for post-splenectomy portal or splenic vein thrombosis (PSVT) due to large splenic vein stump. The relationship between splenic vein diameter (SVD) and PSVT has not been established. Objectives. To invesigate whether SVD is a risk factor for PSVT. Methods. Forty patients who underwent laparoscopic splenectomy were analyzed. Preoperative and postoperative enhanced helical computed tomographic scans were obtained in all patients, and subsequent follow-up was performed in patients with PSVT during anticoagulant therapy. SVDs at the junction of portal vein (PV) 2, 4, and 6 cm from the junction of PV were measured preoperatively and postoperatively. Multivariate analysis was performed using logistic regression model. Results. PSVT was diagnosed in 52.5% (21/40) patients. Preoperative SVD was significantly larger in patients with PSVT than in those without PSVT. Seventy-two percent of patients (16/22) with PSVT in splenic veins with a diameter of > 8 mm developed PSVT. Multivariate analysis identified preoperative SVD as a significant and independent determinant of PSVT At a cutoff value of 8 mm, receiver operator characteristic analysis for prediction of PSVT provided an area under the curve of 0.8552 (95% CI 0.821-1.000). Conclusion. Preoperative SVD is a risk factor for post-splenectomy PSVT. We recommend measurement of SVD preoperatively in patients elected to undergo splenectomy, and a close follow-up of patients with SVD greater than 8 mm. (Surgery 2009;145:457-64.)