ABSTRACT
Aim:
To define the MR appearance of the intact vaginal and paravaginal anatomy.
Method:
the pelvic MR examinations achieved with external coil of 25 nulliparous women (group A), mean age 31.3 range 28-35 years without pelvic floor dysfunctions, were compared with those of 8 women who had cesarean delivery (group B), mean age 34.1 range 31-40 years, for evidence of (a) vaginal morphology, length and axis inclination; (b) perineal body’s position with respect to the hymen plane; and (c) visibility of paravaginal attachments and ligaments.
Results:
in both groups, axial MR images showed that the upper vagina had an horizontal, linear shape in over 91%; the middle vagina an H-shape or W-shape in 74% and 26%, respectively; and the lower vagina a U-shape in 82% of cases. Vaginal length, axis inclination and distance of perineal body to the hymen were not significantly different between the two groups (mean ± SD 77.3 ± 3.2 mm vs 74.3 ± 5.2 mm; 70.1 ± 4.8 degrees vs 74.04 ± 1.6 degrees; and +3.2 ± 2.4 mm vs + 2.4 ± 1.8 mm, in group A and B, respectively, P > 0.05). Overall, the lower third vaginal morphology was the less easily identifiable structure (visibility score, 2); the uterosacral ligaments and the paraurethral ligaments were the most frequently depicted attachments (visibility score, 3 and 4, respectively); the distance of the perineal body to the hymen was the most consistent reference landmark (mean +3 mm, range -2 to + 5 mm, visibility score 4). A failure rate of up to 40% in the depiction of uterosacral, cardinal and round ligaments occurred in both groups.
Conclusions:
nulliparous women and women after cesarean delivery do not differ significantly in their vaginal and paravaginal anatomy. Although MR mapping seems a promising tool, failure to depict any support structure in singular cases cannot be considered evidence of abnormality.