Sonographic imaging of urinoma

Abstract

A 72-year-old Hispanic woman with histologically confirmed endometrial adenocarcinoma underwent laparotomy, total hysterectomy (Piver I), bilateral salpingoophorectomy and pelvic lymphadenectomy. During surgery, access and mobilization of the right ureter were complicated by severe pelvic adhesions. Intraoperative tests for bladder and rectal integrity indicated no apparent lesions. The postoperative period was uncomplicated. Twenty days after discharge, the patient was readmitted with abdominal pain, nausea, vomiting, constipation and fever. Physical examination revealed a moderately tender and distended abdomen. Blood count showed moderate leukocytosis (13.0 × 109/L), granulocytosis (11.34 × 109/L) and raised plasma creatinine (3.3 mg/dL; normal value, 0.6–1.2 mg/dL). Contrast-enhanced computed tomography (CT) revealed accumulation of fluid and gas content in the pelvic space on the left obturator fossa, suggesting the diagnosis of distended bowel loops and abscess formation. The proximal segments of the ureters were mildly distended, with evidence of mesenteric and parietal peritoneal edema. The preliminary diagnosis was retroperitoneal abscess, based on fever, leukocytosis and CT findings. Transperineal and transrectal sonography (A.C.T.) revealed a moderately distended right ureter, and profoundly distended left ureter with evidence of hydronephrosis. The pelvis demonstrated a small amount of free intraperitoneal fluid and a left unilocular-solid encapsulated formation, measuring 7.0 × 5.0 cm, with anechogenic content and echogenic protruding tissue. At its upper pole, color Doppler imaging detected a unidirectional intermittent flow entering the formation's cavity (Figure 1, Videoclip S1). These sonographic findings suggested a left ureteral fistula and antegrade pyelography confirmed the presence of a urinoma (Figure 2). Bilateral nephrostomy was performed and the patient's condition gradually improved, with creatinine levels normalizing in 7 days. Her physical condition remained good at 3 months after operation, and at the time of writing she was scheduled to undergo ureteral reconstructive surgery. Sequential color Doppler ultrasound images (a–c) of the ‘intermittent flow’ (arrow) entering the cavity of the pelvic cystic formation, which led to suspicion of ureteral injury. Sequential pyelographic images (a–d) documenting ureteral injury (arrow) at the distal portion of the ureter (medial wall), and the collection of urine in the pelvic formation (circled). Ureteral injury following gynecological and obstetric surgery is a serious complication, with an incidence estimated to be within the range 0.4–4%1, 2. Radical surgery, gynecological malignant tumors, endometriosis, and long duration and technical difficulties in surgery are all associated with long-term complications of ureteral injuries1, 3, 4. Although most ureteral lesions are detected and repaired during surgery4, it has been reported that a small but sizeable proportion are only recognized a variable amount of time after surgery1, 3. Indeed, the diagnosis of ureteral injury can be challenging5. CT scanning is the recommended primary diagnostic procedure2, 5, but in our case contrast-enhanced CT failed to diagnose the ureteral defect and urine leakage; a valve mechanism or dilution of the scant iodate contrast medium, in comparison to the fluid within the cystic pelvic formation, could explain the failure to visualize the ureteral injury. Ultrasound examination was the first diagnostic approach to identify the ureteral injury, based mainly on observation of an ‘intermittent flow’ entering the cavity of the pelvic ‘pseudocyst’ on color Doppler examination. This sign was evident because of the fluid cavity surrounding the ureteral lesion; however, we are aware that such a sign could not be utilized in the presence of direct urine passage into the free peritoneal cavity. Hence, inconclusive CT scan findings during the postoperative period in a symptomatic patient with a pelvic cystic lesion and urine leakage, characterized by an ‘intermittent flow’ Doppler sign, could indicate a ureteric lesion. SUPPORTING INFORMATION ON THE INTERNET The following supporting information may be found in the online version of this article: Videoclip S1 Doppler ultrasound imaging of the ‘intermittent flow‘ (arrow) entering the cavity of the pelvic cystic formation. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. A. C. Testa atesta@rm.unicatt.it* , A. Gaurilcikas?, A. Licameli , C. Di Stasi , D. Lorusso , G. Scambia*, G. Ferrandina?, * Department of Obstetrics and Gynecology, Universitá Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy, Gynecologic Oncology Unit, Catholic University of Rome, Rome, Italy, Bioimaging and Radiological Sciences, Catholic University of Rome, Rome, Italy, ? Department of Oncology, Catholic University of Campobasso, Campobasso, Italy, ? Department of Obstetrics and Gynecology, Kaunas University of Medicine, Kaunas, Lithuania