Massive ovarian edema (MOO) is a very rare disease characterized by a tumor-like, usually unilateral, enlargement of the ovary.
It characteristically presents in young women ~ 6 to 33 years (mean age ~21 years 4).
Most patients present with intermittent pelvic pain of several months duration +/- an adnexal mass. Abnormal uterine bleeding, elevated androgens and abdominal distension can occasionally be seen.
The most probable cause is thought to be recurrent partial torsion of the mesovarium, with obstruction to the venous and lymphatic returns; on the other hand, the basic process may be stromal hyperplasia or hyperthecosis, while the edema is a secondary phenomenon, probably due to torsion of an abnormal, already enlarged organ.
- Meig syndrome
- precocious puberty in infants due to MOO has been described in the literature 4
It is almost always unilateral and in approximately two-thirds of cases involve the right side.
The imaging features correspond to the degree of torsion and edema. As MOO is caused by chronic or intermittent torsion, imaging appearances will have some overlap with those of ovarian torsion.
May appear like a hypoechoic, hypovascular solid ovarian mass-like lesion; there is the presence of central increased ovarian stroma, and there are multiple follicles arranged in the peripheral cortex.
MRI may also demonstrate an enlarged ovarian mass-like lesion. Described signal characteristics include 4 :
- T1: hypointense
- T2: hyperintense
- T1 C+ (Gd): may show enhancement
Treatment and prognosis
Management options include oophoropexy and occasionally oophorectomy is also considered.
History and etymology
The term massive ovarian edema was first described by Kalstone in 1969.
- ovarian fibromatosis: from long-standing massive ovarian edema 4
- ovarian torsion: twisted pedicle with whirlpool appearance is characteristic
- 1. Umesaki N, Tanaka T, Miyama M et-al. Sonographic characteristics of massive ovarian edema. Ultrasound Obstet Gynecol. 2000;16 (5): 479-81. doi:10.1046/j.1469-0705.2000.00286.x - Pubmed citation
- 2. Lee AR, Kim KH, Lee BH et-al. Massive edema of the ovary: imaging findings. AJR Am J Roentgenol. 1993;161 (2): 343-4. AJR Am J Roentgenol (citation) - Pubmed citation
- 3. Hall BP, Printz DA, Roth J. Massive ovarian edema: ultrasound and MR characteristics. J Comput Assist Tomogr. 17 (3): 477-9. - Pubmed citation
- 4. Coakley FV, Anwar M, Poder L et-al. Magnetic resonance imaging of massive ovarian edema in pregnancy. J Comput Assist Tomogr. 34 (6): 865-7. doi:10.1097/RCT.0b013e3181efdfaa - Pubmed citation
- 5. Lalwani N, Patel S, Ha KY et-al. Miscellaneous tumour-like lesions of the ovary: cross-sectional imaging review. Br J Radiol. 2012;85 (1013): 477-86. Br J Radiol (full text) - doi:10.1259/bjr/92819127 - Free text at pubmed - Pubmed citation