Dados do Trabalho

Título

MRI in Placenta Accreta: A primer for residents

Introdução e objetivo(s)

Placenta accreta is an alteration in placental implantation in which the chorionic villi invade the myometrium and even penetrate the uterine serosa. Depending on the degree of invasion, it is defined as accreta, increta or percreta.
Adequate detection of placental accreta and the extent of invasion into the myometrium allows for appropriate planning of the delivery route, assessment of operative risk, and taking necessary safety measures as a multidisciplinary approach.
Magnetic resonance imaging has emerged as an alternative method of supporting the diagnosis of accreta in the event of an inconclusive ultrasound examination, cases of posterior implantation of the placenta, cases of parametrial involvement, and in determining the degree of trophoblastic invasion.

Método(s)

Define placenta accreta and learn clinical implications of the diagnosis
Identify signs of placenta accreta in MRI, with special detail in differences between placenta accreta and percreta
Expose radiological findings with cases of our institution, all of them surgically and anatomopathological correlated.

Discussão

Suggestive findings of placenta accreta on MRI include low-intensity intraplacental T2 bands, heterogeneous placental intensity, intraplacental hemorrhage, abnormal arrangement of vessels, bulging of the uterine contour, or change in normal uterine morphology. Focal disruptions of the myometrium wall or extension through the myometrium are highly suggestive of placenta increta and percreta. Finally, direct invasion or tenting of the bladder is highly specific for placenta percreta.

Conclusões

MRI is an appropriate alternative in the evaluation of placenta previa and placental accreta, especially when there is uncertainty on ultrasound. Focal or complete changes in the myometrium wall are very specific for placenta increta. Direct invasion or "tenting" of the bladder and discontinuity of the myometrium with extraserous invasion are suggestive of placenta percreta.

Palavras Chave

placenta accreta; accreta in MRI; primer for residents

Arquivos