Abstract
BACKGROUND: With the widespread use and promotion of prenatal diagnosis, the detection of fetal ovarian cysts (FOCs) has become prevalent. However, there is limited research on the magnetic resonance imaging (MRI) findings of these cysts. The aim of this study was to analyze the MRI features of FOCs to enhance diagnostic accuracy, and discuss their prognosis and treatment options. METHODS: A total of 22 cases of FOCs were retrospectively collected in our hospital from January 2016 to June 2024. The MRI findings, prognosis, and treatment were analyzed. RESULTS: In the included cases, the gestational age of initial diagnosis of cysts ranged from 30 to 37 weeks. Most (21/22, 95%) cases involved unilateral cysts, whereas 1 case had bilateral cysts. Among them, there were 14 simple cysts and 8 complex cysts with maximum diameter ranging from 20 to 96 mm. All cysts showed hypointensity on T1-weighted imaging (T1WI). Simple cysts showed uniform hyperintensity on T2-weighted imaging (T2WI). Of the 8 cases of complex cysts, 5 showed mixed signal intensity on T2WI and 3 had fluid-fluid level. There was no statistical difference in the maximum diameter of the cysts and the number of non-operative cases between two groups. However, a significant difference in cyst diameter was observed between the operation group and the non-operation group, with a critical threshold diameter of 5.8 cm. CONCLUSIONS: MRI findings of FOCs are varied, especially in complex cysts. The prognosis and treatment of FOCs mainly depends on the size and dynamic changes of the cyst. If the cyst is smaller than 5 cm, it will disappear spontaneously. Otherwise, it should be operated on in time to preserve the ovarian tissue maximumly and avoid autoamputation of the ovary.