Spencer Netto FAC et al. (2007) Retrograde urethrocystography impairs computed tomography diagnosis of pelvic arterial hemorrhage in the presence of a lower urologic tract injury. J Am Coll Surg [doi:10.1016/j.jamcollsurg.2007.07.025]

The diagnostic work-up of patients who suffer pelvic fracture includes pelvic CT to detect arterial hemorrhage and conventional retrograde urethrography or cystography to detect lower-urinary-tract injury. The appropriate sequence in which these investigations are performed is, however, controversial. Netto and colleagues studied whether retrograde urethrocystography interferes with subsequent visualization of arterial extravasation on pelvic CT.

The authors retrospectively evaluated the data from blunt trauma patients with pelvic fracture and either a bladder or urethral rupture, seen in a single Canadian center between June 2002 and May 2006. Patients were assigned to one of two groups according to the order in which urologic tests (retrograde urethrography and cystography) and pelvic CT were performed: patients in group 1 (n = 23) underwent urologic tests first, and patients in group 2 (n = 26) underwent pelvic CT first.

Indeterminate or false-negative results for pelvic arterial extravasation on pelvic CT were significantly more frequent in group 1 than group 2 (11 of 23 patients versus 0 of 26 patients; P <0.001). Furthermore, patients with indeterminate or false-negative results on CT generally had a longer mean delay before embolization than those with positive CT results.

The authors conclude that the ability of pelvic CT to identify pelvic artery extravasation might be impaired by previously performed retrograde urethrography or cystography, which in turn might delay treatment of pelvic artery hemorrhage.