HIGH RESOLUTION UNENHANCED COMPUTED TOMOGRAPHY IN PATIENTS WITH SWOLLEN LEGS

Abstract

Purpose: To evaluate the accuracy of computed tomography (CT) scan imaging indistinguishing lymphedema from deep venous thrombosis (DVT) and lipodystrophy (lipedema) inpatients with swollen legs.Material and Methods: CT scans of the lower limbs were performed in 55 patients with 76swollen legs (44 lymphedemas, 12 DVT and 20 lipedemas). Thirty-four normal contralateral legswere also similarly evaluated. Primary lymphedema was verified by lymphography orlymphoscintigraphy, whereas secondary lymphedema was documented by a typical clinicalhistory. DVT was established by ultrasound Doppler imaging. The diagnosis of lipedema wasmade with bilateral swollen legs where lymphoscintigraphy and Doppler examination were bothunremarkable. Qualitative CT analysis was based on skin thickening, subcutaneous edemaaccumulation with a honeycombed pattern, and muscle compartment enlargement.Results: Sensitivity and specificity of CT scan for the diagnosis of lymphedema was 93 and100%, respectively; for lipedema it was 95 and 100%, respectively; and for DVT it was 91 and99%, respectively. Skin thickening was found in 42 lymphedemas (95%), in 9 DVT (75%), and in2 lipedemas (16%). Subcutaneous edema accumulation was demonstrated in 42 legs (95%) withlymphedema and in 5 (42%) with DVT but in none with lipedema. A honeycombed pattern waspresent only in lymphedema (18 legs or 41%); muscle enlargement was present in all patientswith DVT, in no patient with lipedema, and in 4 (9%) with lymphedema.Conclusion: Edema accumulation is readily demonstrated with plain CT scan and is notpresent in lipedema. Specific CT features of the subcutaneous fat and muscle compartmentsallow accurate differentiation between lymphedema and DVT.