THE ROLE OF ULTRASOUND IN THE EARLY DETECTION OF ACUMS
By Rebecca Slough, Cambridge University Hospitals NHS Foundation Trust
ACUMs are rare congenital myometrial lesions; patients usually present with severe dysmenorrhoea, which is more commonly in young women.
We explore this case of a 35-year-old female with a history of heavy menstrual bleeding, dysmenorrhoea and dyspareunia, and it is worth noting, they are also under investigation for endometriosis. The initial Ultrasound acquired at an acute NHS Trust, demonstrated a well-defined cystic mass directly adjacent to the right uterine wall. The cystic component has a ground-glass appearance, consistent with blood products and therefore may be confused for an endometrioma. Observations included peripheral vascularity; given these appearances, an ACUM remains in the differential.
Common alternative diagnoses may include adenomyosis, endometrioma, or a fibroid (haemorrhagic degeneration). Additional differential diagnoses in this particular case include a unicornuate uterus or a functioning non-communicating rudimentary horn.
Accurate distinction between these conditions requires practitioners to consider several key imaging and clinical features. Endometrioma typically present as homogeneous, low-level internal echoes on ultrasound due to the presence of blood. However, ACUMs can also contain blood products, leading to potential confusion. Notably, peripheral vascularity seen on Doppler imaging is more suggestive of an ACUM than an endometrioma.
Practitioners should refer patients for an MRI when ultrasound findings are inconclusive or when the clinical presentation includes severe symptoms not adequately explained by common conditions like endometriomas, adenomyosis or fibroids. Early referral for MRI is crucial for accurate diagnosis, as delayed or incorrect diagnosis can lead to suboptimal treatment. In cases of confirmed ACUM, surgical interventions, often involving excisions, are required to alleviate symptoms and prevent complications.
By following these guidelines and utilising follow-up MRI, we can ensure accurate diagnosis and optimal management of rare gynaecological anomalies such as ACUMs, thereby improving our patient outcomes.