BACKGROUND: Laparoscopic splenectomy is an effective treatment for many patients with immune thrombocytopenic purpura (ITP) who fail or relapse after treatment with steroids. Patients with an incomplete response to splenectomy and those who experience recurrence of symptoms should be evaluated for the presence of an accessory spleen. The clinical effectiveness of laparoscopic excision of an accessory spleen after a previous splenectomy for ITP has varied in different studies. Laparoscopic intraoperative identification of an accessory spleen can be difficult. The authors report their experience with laparoscopic accessory splenectomy (LAS) and the use of perioperative localization methods for this procedure. METHODS: This study reviewed seven consecutive patients who underwent LAS, after initial splenectomy failed to cure ITP, at a tertiary care center between April 9, 2003 and March 31, 2008. Demographics, diagnostic and localization studies, technical success, and the effect on thrombocytopenia were examined. The location of the accessory spleen also was recorded. A novel method for localizing accessory spleen was used. It consisted of preoperative computed tomography (CT)-guided injection of methylene blue at the accessory spleen's site, preoperative intravenous injection of 99m-technetium-labeled, heat-damaged red blood cells, or both. Intraoperatively, the dye was used for visual identification, and the gamma probe was used to aid in locating and confirming the presence of the accessory spleen in the excised specimen. RESULTS: Seven patients with recurrent ITP after initial failed splenectomy underwent LAS during the study period. Five of these patients had the initial splenectomy performed laparoscopically. All seven patients had successful laparoscopic removal of the accessory spleen based on a final pathologic examination. One patient required the second laparoscopic exploration with perioperative localization after a failed attempt without it. These perioperative localization methods were used in subsequent operations on other patients. These methods were found to be helpful in the intraoperative identification of the accessory spleens. The accessory spleens missed at initial splenectomy were found in unusual locations. Five of the seven patients had sustained improvement in platelet counts after LAS. One patient had a postoperative ileus that resolved with nonoperative management. No other complications or mortality was observed. CONCLUSION: The LAS procedure after previous splenectomy is feasible and safe. Perioperative localization methods aid in the intraoperative identification of an accessory spleen. Accessory spleens missed at initial splenectomy are generally found in unusual locations. Treatment of recurrent or unresolved ITP with LAS can be effective for some patients.