Introduction: Adenomyosis diagnosis has improved substantially with high-resolution transvaginal ultrasound and the standardized Morphological Uterus Sonographic Assessment (MUSA) criteria; however, the relative diagnostic contribution of individual sonographic signs to histopathological confirmation remains incompletely defined. This study evaluated clinical and ultrasonographic markers associated with histopathologically confirmed adenomyosis.

Materials and methods: We conducted a single-center prospective observational study of consecutive women scheduled for hysterectomy at a tertiary referral center. Clinical symptoms and a comprehensive set of direct and indirect MUSA criteria were systematically recorded using a standardized reporting form. Associations with histopathologically confirmed adenomyosis were evaluated by univariate logistic regression; Odds Ratios (OR) with 95% Confidence Intervals (CI) and corresponding p-values are reported. A multivariable model was not constructed owing to sample size constraints and the exploratory nature of the study.

Results: Clinically, Heavy Menstrual Bleeding (HMB) demonstrated the strongest association with adenomyosis (OR=4.81, 95% CI: 2.33–9.92; p<0.001), followed by dyspareunia (OR=1.11, 95% CI: 1.01–1.23; p=0.02). Dysmenorrhea, chronic pelvic pain, dyschezia, and dysuria were not statistically significant predictors in univariate analysis. Ultrasonographically, five MUSA criteria demonstrated statistically significant associations with histopathologically confirmed adenomyosis: subendometrial echogenic lines/buds (OR=8.51, 95% CI: 2.20–32.9; p<0.001), myometrial asymmetry (OR=6.88, 95% CI: 2.22–21.3; p<0.001), myometrial heterogeneity (OR=4.96, 95% CI: 1.28–19.3; p=0.015), myometrial cysts (OR=3.30, 95% CI: 1.67–6.56; p<0.001), and junctional zone irregularity (OR=2.57, 95% CI: 1.18–5.40; p=0.047). In contrast, uterine size in the leiomyoma-free subset, myometrial shadowing patterns, lesion vascularization, lesion echogenicity, and lesion definition demonstrated no statistically significant associations with adenomyosis. Hyperechoic islands showed a non-significant trend toward association with adenomyosis (OR=2.67, 95% CI: 0.94–7.52; p=0.058). Myometrial cysts demonstrated a sensitivity of 67.3% and specificity of 61.6%; subendometrial echogenic lines/buds showed lower sensitivity (17.3%) but higher specificity (97.6%) for histopathologically confirmed adenomyosis.

Conclusion: Transvaginal ultrasound incorporating MUSA criteria is clinically useful for preoperative adenomyosis diagnosis, particularly through markers like subendometrial lines, myometrial asymmetry, heterogeneity, cysts, and junctional zone irregularity.

Adenomyosis, Transvaginal ultrasound, MUSA criteria, Myometrial cysts, Subendometrial echogenic lines, Junctional zone, Heavy menstrual bleeding, Dyspareunia, Hysterectomy