Evaluation of Crossing Vessels in Patients with Ureteropelvic Junction Obstruction by Means of Helical CT

Abstract

Helical computed tomography (CT) was used to demonstrate the distribution of crossing vessels in patients with ureteropelvic junction (UPJ) obstruction for planning surgical management. Twenty patients with symptomatic UPJ obstruction were evaluated with dual-phase contrast material-enhanced helical CT. In addition to axial images, coronal, sagittal, and curved paracoronal images along the crossing vessels or the UPJ were obtained by means of multiplanar reconstruction. Crossing vessels were evaluated according to type, position, and association with UPJ obstruction. Fifteen vessels in 12 of the 20 patients were found to cross the UPJ at helical CT. Nine vessels were arteries and six were veins; seven vessels crossed anteriorly and eight crossed posteriorly. In 11 patients, crossing vessels were thought to be associated with UPJ obstruction at helical CT; retroperitoneoscopic repair was performed, and the diagnosis was found to have been accurate in all except one. In the eight patients in whom no significant vessels were seen and the one patient in whom the crossing vessel was not associated with UPJ obstruction at helical CT, endopyelotomy was performed and UPJ obstruction was relieved, with no complications. Helical CT is useful for evaluation of vessels crossing the UPJ and for planning surgical management.

Vascular Renal Anatomy and the Ureteropelvic Junction: Preoperative Multidetector CT Scanning with Split-Bolus Injection as a Predictor of Laparoscopic Findings

“…Previous anatomic investigations have shown that vessels have a close relation to the UPJ in approximately 75% of patients with the syndrome. 3,4,8,9 This rate was confirmed here, with 63% of the present series exhibiting an inferior-pole pedicle.…”

“…3,4,9 However, the literature provides few data on correlations between MDCT and surgical findings; our study showed an excellent correlation.…”

“…These advantages have enhanced the imaging of small vessels. 3,4,8,11,12 In our study, all the arteries observed during the laparoscopic approach were detected by MDCT. Classically, digital subtraction angiography (DSA) with selective injections is considered to be the standard of reference in depicting polar arteries.…”

“…Although some reports claim that crossing vessels have been implicated in UPJ obstruction, these vessels more commonly aggravate rather than cause the obstruction. [2][3][4][5][6][7][8] Computed tomography scanning is the only technique that can provide all the necessary information in a single examination.…”

“…Diuretic injection in patients with UPJ obstruction occasionally leads to renal colic pain; however, this responds rapidly to antispasmodic and anti-inflammatory drugs. 3,4 There is, as yet, no widely accepted dedicated CT urography protocol for optimal opacification and distention of the collecting system. 13 The injection of a diuretic leads to rapid and uniform distribution of contrast material through the urine and is more efficient than other procedures such as saline serum injection.…”