Placement of a shape-memory alloy intraurethral catheter (memokath®) using transrectal ultrasonography and fluoroscopy

Abstract

Intraurethral catheters are effective in the treatment of elderly patients with benign prostate hyperplasia (BPH) who have severe complications. However, it is not easy to measure the length of the prostatic urethra and to determine an appropriate location for the urethral catheter using only fluoroscopy, especially in patient with severe mid-lobe enlargement. We attempted to place a shape-memory alloy intraurethral catheter (MEMOKATH®) by transrectal ultrasonography and fluoroscopy to measure the precise length of the prostatic urethra and to determine an appropriate location for an intraurethral catheter placement. Patients were given urethral infiltration anesthesia with 2% lidocaine hydrochloride jelly and placed in the supine position. Both transrectal ultrasonography and fluoroscopy were performed to observe the bladder neck, the apex of the prostate gland, and the prostatic urethra. Transrectal ultrasonography was shown to depict them more clearly than fluoroscopy. Transrectal ultrasonography was also shown to be more suitable than fluoroscopy for measuring the prostatic urethra length, as well as for accurately positioning the MEMOKATH®stent, especially in cases of BPH with midlobe enlargement. The MEMOKATH® stent was placed in 7 patients with BPH. Urethral catheters had been put in place in 6 of these patients because of urinary retention, and large amounts of residual urine were found in the remaining patient. Three patients had severe mid-lobe enlargement. All patients were able to urinate without much residual urine after the procedure. No severe complications were noted. Transrectal ultrasonography is useful for accurately placing the MEMOKATH® stent, as it provides more objective and detailed anatomical findings than fluoroscopy.