ABSTRACT
Urinary incontinence is a distressing condition which leads to medical and psychological problems in women. Intrinsic and extrinsic properties of the urethrovesical junction [bladder neck] allow maintenance of urinary continence at rest and with activity. The goal of this study was to clarify the anatomical structures responsible for the urinary continence control system. Also, to set a basis for ultrasonographic evaluation of the urethrovesical junction [bladder neck] through transvaginal and transperineal approaches. Prospective study done in Anatomy department and University teaching hospital. Anatomic study: Ten human female cadavers were used. Dissection of the abdominopelvic region and sagittal sections were made. Assessment of the position of the urethrovesical junction [bladder neck] in relation to the symphysis pubis was done. The following parameters were measured: Distance between bladder neck and the posterior midpoint of symphysis pubis [distance 1], -Distance between bladder neck and lower border of the symphysis pubis [distance 2], -Posterior urethrovesical angle. Ultrasonographic study: One hundred healthy continent volunteer women were examined by transvaginal [with empty and full bladder] and transperineal ultrasonography [with full bladder] for evaluation of the bladder neck at rest and during straining. Measurements of distance 1, distance 2, Posterior urethrovesical angle, and bladder neck descent during straining were done. The anatomical study revealed that the urethral support system consisted of anterior vaginal wall, endopelvic fascia, arcus tendineus fasciae pelvis, and levator ani muscles. Distance 1 ranged between 12 to 24 mm with a mean of 16 mm, while distance 2 ranged between 15 to 33 mm with a mean of 23 mm and the posterior urethrovesical angle ranged between 70 to 85 degrees with a mean of 80 degrees. The ultrasonographic study revealed that: a-In empty bladder: distance 1 ranged betweenli and 16 mm with a mean of 12.5 +/- 3.5 mm at rest and between 13 to 18 mm with a mean of 14 +/- 4.' mm during straining, while distance 2 ranged between 12 to 18 mm with a mean of 14 +/- 3.9 mm at rest and between 15 to 20 mm with a mean of 16 +/- 5.1 mm during straining. Bladder neck descent during straining ranged between 1 to 5 mm with a mean of 2.5 +/- 1.1 mm. b-In full bladder: distance 1-ranged between 10 to 15 mm with a mean of 11.5 +/- 3.4 mm at rest, while during straining it ranged between 14 to 20 mm with a mean 15 +/- 4.5 mm. Distance 2-ranged between 11 to 16 mm with a mean 12 +/- 3.3 mm at rest; while during straining it ranged between 17 to 24 mm with a mean 18.5 +/- 4.4 mm. Bladder neck descent during straining ranged between 1 to 8 mm with a mean of 4.5 +/- 1.5 mm. The urethrovesical angle was acute at rest and right angle during straining in empty urinary bladder, to turn into right angle at rest and slightly obtuse during straining in full urinary bladder. Understanding of the normal anatomical urethral support system with special reference to urethrovesical junction and ultrasonographic evaluation of the urethrovesical angle in healthy women can help the urogynecologists in the correct diagnosis and management of female genuine stress incontinence