[Spontaneous Resolution of Renal Artery Pseudoaneurysm after Robotic-Assisted Partial Nephrectomy]

Partial nephrectomy (PN) for small renal tumors has become increasingly common. Complications of PN include renal artery pseudoaneurysm (PA), a potentially life-threatening condition. However, the true incidence and natural history of PA after PN remain unclear. Therefore, we conducted a retrospective study of the radiographic characteristics of robotic-assisted partial nephrectomy (RAPN) observed during the postoperative period. We selected 36 consecutive patients with renal carcinoma who underwent RAPN at our institution between December 2016 and May 2019. Patients with contraindications for the use of contrast medium were excluded. A total of 31 eligible patients underwent computed tomography angiography (CTA) during the early postoperative period after RAPN and the incidence of PA was evaluated. Among the patients with PASs, asymptomatic PAs were followed without intervention and their clinical course was assessed using CTA at 1 to 3 months postoperatively. PA was identified in 5 out of 31 (16.1%) patients after RAPN. Median duration between PN and the first CTA was 6 days (range, 1-8). Median PA size was 13 mm (range, 8-17). All (100%) PAs were asymptomatic and resolved spontaneously, as verified by CTA during the late postoperative period. Median duration between identification of PA on early postoperative CTA and subsequent resolution was 92 days (range, 35-106). Our findings indicated that asymptomatic PA after PN can be followed without intervention.