Dados do Trabalho

Title

Adenomyosis - the Radiologist's Perspective

Objective

This poster presents an overview of adenomyosis from the radiologist's perspective, emphasizing the significance of non-invasive diagnostic techniques. It offers an in-depth analysis of transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI) findings, reviews their respective attributes, and discusses potentially associated conditions.

Methods

Adenomyosis is a benign condition characterized by the presence of heterotopic endometrial tissue within the myometrium, most probably due to invagination of the basal endometrial layer. These heterotopic endometrial cells continuously express high levels of estrogen receptors and apoptosis-suppressing mediators, leading to smooth muscle cell hypertrophy and hyperplasia.
The prevalence of adenomyosis is highly variable due to demographic factors and non-uniform diagnostic criteria. Nevertheless, several risk factors, such as estrogen exposure, parity, and prior uterine surgery, have been identified. Patients most frequently present with menorrhagia, dysmenorrhea, and chronic pelvic pain, as well as increased risk of infertility and adverse pregnancy outcomes, including miscarriage. Given its significant prevalence and associated complications, determining an accurate non-invasive diagnostic approach is paramount.
The accuracy of TVUS and MRI in diagnosing adenomyosis has been demonstrated, exhibiting specificities of 78% and 88%, respectively, and an equal sensitivity of 78%. However, since TVUS is highly operator-dependant and these results are primarily derived from expert-led studies, its performance is possible overestimated. Notwithstanding, TVUS widespread accessibility, lower cost, and shorter acquisition times make it the preferred initial imaging method. MRI, on the other hand, is mainly used as a secondary diagnostic technique due to its higher cost, longer acquisition times, and potential discomfort for certain patients, namely with claustrophobia. Yet, it remains relevant, as its superior soft tissue contrast resolution and multiplanar reconstructions allow for a better definition of the junctional zone and the diagnosis of potential estrogen-dependent conditions, such as fibroids and endometriosis.
Using illustrative images from our institution's TVUS and MRI scans, we showcase a variety of adenomyosis manifestations discernible through both imaging methods.

Results

Multiple authors have proposed classification systems for reporting adenomyosis on TVUS and MRI. However, they have yet to achieve validation and universal acceptance. Our approach emphasizes a classification from a histopathological perspective, distinguishing signs as either direct, correlating to ectopic endometrial foci, or indirect, corresponding to secondary myometrial hypertrophy. Direct signs tend to increase specificity, while indirect signs enhance diagnostic sensitivity. We detail and depict the distinct imaging manifestations and signs, establishing a correlation between TVUS and MRI.

Conclusion

Over the last few decades, advancements in non-invasive imaging techniques have facilitated the diagnosis of adenomyosis without requiring a surgical-histopathological procedure. This progress has enhanced physicians' understanding of the true incidence of adenomyosis within the general population and its clinical manifestations. Concurrently, comprehending the key imaging findings is vital for performing a non-invasive adenomyosis diagnosis. Understanding these findings' histopathological background and diagnostic value allows for better interpretation, identifying potential pitfalls, and detecting frequently associated conditions. The resulting comprehensive imaging assessment not only detects adenomyosis, but also guides the therapeutic strategy.

Keywords

Adenomyosis, Imaging, Magnetic Resonance Imaging, Ultrasound