[Diagnostic study of the usefulness of virtual endoscopic images and 3-D modeling for lower urinary tract obstruction].

Purpose: I observed bladder and urethral morphology and lumen by making a virtual endoscopy (VE) of the bladder and a urethra for patients with lower urinary tract symptoms. I have herein reported the procedures to use this model to evaluate the condition of patients more precisely.

Patients And Methods: Of those referred for investigation of lower urinary tract symptoms, subjects were 22 boys (5-13 years old, mean 9) in whom voiding cystourethrography (VCUG) was suspected for urethral obstruction between March, 2009 and October, 2010. Eleven of these 22 cases were extracted at random and underwent voiding computed tomography (VCT). Except one dropped out, the 21 cases were assigned to a VCT/VCUG combination group or a VCUG-single group. We confirmed the two groups, the rate of agreement of imaging views and cystourethroscopy (CS) views, and the effectiveness of endoscopic operation.

Result: I made the following imaging diagnoses in the VCT/VCUG combination group: congenital obstructive posterior urethral membrane (COPUM), n = 7; Cobb's collar, n = 1; and COPUM and Cobb's collar combined, n = 3. In contrast, in the VCUG-single group, I diagnosed COPUM, n = 5; bulbar region urethral stricture, n = 2; posterior urethral expansion, n = 2; and bladder form abnormality, n = 1. The rate of agreement between preoperative diagnosis and CS views on imaging was 72.7% in the VCT/VCUG combination group, and 33.3% in the VCUG-single group. All patients underwent transurethral incision (TUI) of the urethral obstruction. In the VCT/VCUG combination group, effectiveness of the TUI was assessed as good in 2 cases and moderate in 6 cases giving an overall effectiveness rate (good + moderate) of 72.7%. In the VCUG-single group, effectiveness was rated as moderate in 5 cases (overall effectiveness rate = 50%).

Conclusion: I developed a method of VE for lower urinary tract obstruction of children and examined the effectiveness. This method was found to be more effective than conventional urinary tract imaging. With the developments in the equipment, this method may in future be useful as an adjunct to CS and urodynamic studies.