LEARNING FROM IMAGES Seroma Related to Prosthetic Arteriovenous Graft

Seroma is a complication unique to prosthetic arteriovenous graft (AVG), resulting as a consequence of transudation of sterile and clear serum, which is confined by a non-secretory fibrous pseudomembrane [1]. Although the precise etiology remains elusive, it is thought to be related to failure of the surrounding connective tissue to incorporate the graft [2]. The incidence of 2-4% reported in literature may not be a true representation due to frequently seen spontaneous resolution of seroma [2]. A seroma is typically located close to the arterial anastomosis and usually occurs within the first month after placement of the AVG [3] (Fig. 1). Ultrasound-guided needle aspiration of the fluid yielding serous or gelatinous material can be of both diagnostic and therapeutic significance. When in doubt, the fluid should be