Radiographic Urethrocystography part 2
Standard lateral upright and straining cystogram
Parameters of urethrocystography
Comparability of perineal ultrasound and lateral urethrocystography
Comparability of perineal ultrasound (PU) and lateral urethrocystography
Comparing PU scanning and radiologic scanning of BN by use of a chain and catheter, there is good correlation between two techniques. Ultrasound scanning is preferred, as it avoids irradiation, accurate, portable and available in most gynecologic departments (Gordon et al, 1989). Perineal scan provides similar information to that obtained by radiographic procedure without exposure to X-rays (Koelbl et al, 1988). Perineal ultrasound is a reliable technique that allows reproducible static and dynamic evaluation. Lateral urethrocystography is superior to perineal ultrasound only if BN funneling is the aim of evaluation (because contrast medium enters BN when the SU incontinent patient performs a Valsalva’s maneuver); it is inferior if BN mobility during maximum Valsalva is being investigated. Several advantages of PU could be demonstrated (patient’s contrast, lack of irradiation, dynamic anatomic illustration during pressing, coughing and pelvic floor contraction) (Schaer et al, 1995 I).
Recent progress indicates that sonography holds the key to the future of imaging in urogynaecology (Schaer, 1997). Both methods allow anatomic assessment of the BN and have different strengths and weakness (Dietz and Wilson, 1998).
Perineal sonographic procedure performed without introduction of a catheter into urethra, the urinary bladder, urethra and symphysis as well as vagina and rectum can be visually represented in sagittal section through the minor pelvis. A comparison with traditional x-ray findings showed a good correlation at 96%. In relation to predictive value, perineal sonography may thus be considered a true alternative to radiology (Grischke et al, 1989).
Measured values of both methods corresponded at rest, while during straining the values are different. During Valsalva’s maneuver, the ultrasound method reflects the mobility of the BN better. The differences between the supine and upright positions were minor in the ultrasound examination, although the funneling of the BN could be detected in the upright position. Except for the funneling of the BN, typical findings of incontinence can be better shown with PU (Schaer et al, 1994).