Transrectal Linear Array Ultrasonography Complements Urodynamics and Can Reduce Cine' Radiation Exposure



In the investigation of the functions of the bladder and urethra, urodynamics with radiologic cine' need dye and there is an exposure to radiation.

Instead we incorporated ultrasonography (US) as an integral part of urodynamics to study neuromuscular dysfunctions of the bladder about 30 years ago.

Methods and Materials

Out of 449 studied, 339 were spinal cord injury (SCI) patients. Mean age was 38.4 years (range 19 to 68 years.), 389 were combined transrectal sonographic and urodynamics studies and 265 were sonographic studies performed independently without the use of catheters. Multiple studies were performed in some patients.Spinal Cord Injury patients were studied in a lithotomy position. A 5 MHz linear array transducer is used with 64 t0 110 piezoelectric elements, arranged in a straight line to provide a sagittal picture of the base of the bladder, bladder neck and almost whole urethra.


Transrectal sonography demonstrated that 162/339 (47%) SCI had a bladder neck ledge and only 2/110 (1.8%) non SCI patients showed a posterior bladder neck ledge. The ledge over 0.5 cm projecting from the posterior bladder neck region producing a significant bladder neck obstruction was demonstrated in 28% patients on intermittent catheterization. This was associated with detrusor sphincter dyssenergia (p value<0.0005, Mann-Whitney test). Other bladder neck abnormalities visualized and detected easily included bladder neck excessive sensitivity, hyperreflexic bladder, stenosis of the bladder neck, and median lobe of the prostate. Patients with severe detrusor hyperreflexia were difficult to evaluate with pressure flow studies since catheter introduction induced bladder contractility but could be easily evaluated with ultrsonography without using a urodynamic catheter. The urethral abnormalities such as urethral false passages, detrusor sphincter dyssenergia and urethral strictures detected on ultrsonography were not easily recognized by radiologic studies alone. Therapeutic usefulness of the sonography included an easy insertion of the catheter with false passages.


The application of rectal ultrasonography using a linear array rectal transducer was able to provide equal or even better images of the micturition process than micturition cystourethrography (MCU). An adequate and accurate real time image of the bladderneck, the prostatic urethra and the external urethral sphincter could be obtained in all instances.The application of rectal ultrasonography using a linear array rectal transducer was able to provide equal or even better images of the micturition process than micturition cystourethrography(MCU). Transrectal linear array transducer makes possible a sagittal view of the bladder base-plate, prostatic urethra, and membranous urethra yielding an image similar to that obtained with voiding cystourethrogram. This does not limit evaluation due to radiation exposure, such as imposed by the use of fluoroscopy, and the possibility of visualizing not only the lumen of the bladder neck and urethra but also the surrounding soft tissue. Using ultrasonographic urodynamics in neuromuscular dysfunctions of the bladder and urinary voiding obstructions we could diagnose easily detrusor-sphincter dyssynergia and secondary bladder neck obstruction due to a posterior ledge at the bladder neck.



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