Anatomy and segmental vascularization: the splenic artery typically divides into 2-3 segmental branches (upper polar, mid, lower polar) at or near the hilum. Selective ligation of one segmental branch produces a clear demarcation line on the spleen, allowing parenchymal transection along the avascular plane. Preservation of >25% functional parenchyma is sufficient to maintain immune function and reduce overwhelming post-splenectomy infection (OPSI) risk by encapsulated organisms (S. pneumoniae, H. influenzae, N. meningitidis). Indications - benign splenic cysts (>5 cm or symptomatic), hamartoma, hemangioma, lymphangioma, focal abscess after drainage, contained AAST grade II-III trauma in hemodynamically stable patients, accessory spleen excision in ITP failure.
Preoperative evaluation and contraindications: contrast-enhanced CT or MRI to define lesion location, size, segmental vascular relations, and feasibility of partial resection (peripheral lesions are ideal). Preoperative vaccination against encapsulated organisms (PCV13 + PPSV23, MenACWY, MenB, Hib) ≥14 days before surgery as backup if conversion to total splenectomy is required. Preoperative platelet count (>50K), coagulation profile, splenic artery embolization can be considered to reduce intraoperative bleeding. Contraindications - lesions involving hilum, multiple bilateral lesions, malignancy (lymphoma, metastasis - oncologic principles favor total splenectomy), portal hypertension with massive splenomegaly, severe coagulopathy, hemodynamic instability with high-grade trauma.
Operative technique: 4-5 ports configuration in right lateral decubitus position (45-90°). Steps - 1) mobilization by division of splenocolic, splenorenal, gastrosplenic, splenophrenic ligaments preserving short gastric vessels in upper-pole resections; 2) identification of segmental splenic artery branch supplying the target segment; 3) selective ligation/clipping of segmental artery; 4) demarcation line waiting (5-10 minutes); 5) parenchymal transection along demarcation using ultrasonic dissector (Harmonic), advanced bipolar (LigaSure), or staplers (Endo-GIA with vascular load); 6) hemostasis with bipolar, hemostatic agents (TachoSil, Surgicel, Floseal), and selective suture; 7) specimen retrieval in endoscopic bag. Outcomes - bleeding 5-10%, conversion to total splenectomy 5-15%, abscess 2-3%, mortality <0.5% in elective cases.