New MUSA classification of adenomyosis: correlation of symptoms and clinical severity with direct and indirect features

Abstract

Introduction: To correlate the direct and indirect morphological uterus sonographic assessment (MUSA) features of adenomyosis with clinical symptoms severity.

Material and methods: This observational prospective study was conducted at a tertiary care institute from April 2023 to March 2024, involving 254 women aged 18 to 45 years with a regular menstrual cycle and ultrasound-confirmed diagnosis of adenomyosis. Detailed clinicodemographic data were collected, including symptoms such as painful menses, heavy menstrual bleeding (HMB), chronic pelvic pain (CPP), and bowel/bladder symptoms. Severity of symptoms was graded using a visual analogue scale and pictorial blood loss analysis chart. All participants underwent a 2D transvaginal ultrasound during the secretory phase, performed by blinded sonographers. Diagnosis of adenomyosis was based on the presence of direct or indirect MUSA features.

Results: The study's primary findings showed that 94.4% of participants had at least one direct feature, with myometrial cysts being the most common (83.75%). Statistical analysis revealed significant associations between clinical symptoms and specific MUSA features. Heavy menstrual bleeding was linked with asymmetrical myometrial thickening, interrupted junctional zone, and globular uterus. Chronic pelvic pain was significantly associated with myometrial cysts, and dysmenorrhoea was linked with myometrial cysts and hyperechogenic islands. On stepwise logistic regression, HMB was found to be significantly associated with asymmetrical myometrial thickening, interrupted JZ, and globular uterus with odds ratios (OR) of 2.84, 2.01, and 4.03, respectively. Chronic pelvic pain was significantly associated with myometrial cyst (OR = 3.07), as was dysmenorrhoea (OR = 1.13).

Conclusions: The findings of the study highlight that few sonographic direct and indirect signs of adenomyosis are linearly associated with the severity of disease symptoms.

Keywords: 2D ultrasound; MUSA; adenomyosis; chronic pelvic pain; heavy menstrual bleeding.