Paraovarian cysts are also sometimes referred to as paratubal cysts or hydatid cysts of Morgagni 14.
They typically occur in women at the ages of 20-40 years old.
Most are asymptomatic, although patients with large lesions can present with pelvic pain.
They usually occur around the broad ligament and arise from paramesonephric, mesothelial, or mesonephric remnants. They are usually simple cysts (although some authors include paraovarian cystadenomas under the umbrella of paraovarian cysts).
A paraovarian cyst is easier to recognize if the ipsilateral ovary is demonstrated to be separate from it.
- typically thin-walled and smoothly marginated
- typically unilocular simple cyst (in ~66%); rarely multilocular (~4%)
- cyst moves independently of ovary when transducer pressure is applied
- rarely, a soft tissue nodule in the cyst may indicate the development of a neoplasm 9
Often seen located close to the ipsilateral round ligament and are often of homogenous signal intensity.
In uncomplicated cases, signal characteristics usually follow that of fluid 12.
- can be hyperintense if complicated by hemorrhage
Other features include
- beak sign 11
Treatment and prognosis
Paraovarian cysts occasionally can be complicated by rupture, torsion, or hemorrhage. Large or symptomatic cysts often undergo surgical resection. Smaller asymptomatic ones are treated conservatively.
Given a small chance of representing neoplasm, paraovarian cystic lesions may be recommended for follow-up imaging. Societal guidelines differ in this regard.
The 2010 Society of Radiologists in Ultrasound consensus statement recommends follow-up of simple paraovarian cysts in situations similar to that of simple ovarian cysts 13:
- 5-7 cm simple cyst in premenopausal women: yearly ultrasound
- 1-7 cm simple cyst in potmenopausal women: yearly ultrasound
- >7 cm simple cyst in any age: further imaging (e.g., MRI) or surgical evaluation
In contrast, the American College of Radiology Ovarian-Adnexal Reporting and Data System (O-RADS) for ultrasound, published in 2019, recommends the following 15:
- any size simple paraovarian cyst in premenopausal women: no follow-up
- any size simple paraovarian cyst in postmenopausal women: optional single follow-up study in 1 year
- nonsimple paraovarian cysts: management dependent on risk stratification as per ovarian criteria
Finally, the American College of Radiology Incidental Findings Committee on adnexal findings on CT or MRI recommends that for paraovarian cysts with characteristic features, further imaging is usually unnecessary 16.
For an adnexal cystic lesion consider:
- 1. Gopal K, Lim Y, Dobson M et-al. A case of torted parafimbrial cyst on MRI: case report and review of the literature. Br J Radiol. 2006;79 (948): e208-10. doi:10.1259/bjr/23068987 - Pubmed citation
- 2. Adusumilli S, Hussain HK, Caoili EM et-al. MRI of sonographically indeterminate adnexal masses. AJR Am J Roentgenol. 2006;187 (3): 732-40. doi:10.2214/AJR.05.0905 - Pubmed citation
- 3. Kier R. Nonovarian gynecologic cysts: MR imaging findings. AJR Am J Roentgenol. 1992;158 (6): 1265-9. AJR Am J Roentgenol (citation) - Pubmed citation
- 4. Athey PA, Cooper NB. Sonographic features of parovarian cysts. AJR Am J Roentgenol. 1985;144 (1): 83-6. AJR Am J Roentgenol (abstract) - Pubmed citation
- 5. Barloon TJ, Brown BP, Abu-yousef MM et-al. Paraovarian and paratubal cysts: preoperative diagnosis using transabdominal and transvaginal sonography. J Clin Ultrasound. 24 (3): 117-22. doi:10.1002/(SICI)1097-0096(199603)24:3<117::AID-JCU2>3.0.CO;2-K - Pubmed citation
- 6. Alpern MB, Sandler MA, Madrazo BL. Sonographic features of parovarian cysts and their complications. AJR Am J Roentgenol. 1984;143 (1): 157-60. AJR Am J Roentgenol (abstract) - Pubmed citation
- 7. Moyle PL, Kataoka MY, Nakai A et-al. Nonovarian cystic lesions of the pelvis. Radiographics. 30 (4): 921-38. doi:10.1148/rg.304095706 - Pubmed citation
- 8. Brown DL, Dudiak KM, Laing FC. Adnexal masses: US characterization and reporting. Radiology. 2010;254 (2): 342-54. doi:10.1148/radiol.09090552 - Pubmed citation
- 9. Kim JS, Woo SK, Suh SJ et-al. Sonographic diagnosis of paraovarian cysts: value of detecting a separate ipsilateral ovary. AJR Am J Roentgenol. 1995;164 (6): 1441-4. AJR Am J Roentgenol (abstract) - Pubmed citation
- 10. Korbin CD, Brown DL, Welch WR. Paraovarian cystadenomas and cystadenofibromas: sonographic characteristics in 14 cases. Radiology. 1998;208 (2): 459-62. Radiology (abstract) - Pubmed citation
- 11. Kishimoto K, Ito K, Awaya H et-al. Paraovarian cyst: MR imaging features. Abdom Imaging. 27 (6): 685-9. doi:10.1007/s00261-002-0014-6 - Pubmed citation
- 12. Imaoka I, Wada A, Kaji Y et-al. Developing an MR imaging strategy for diagnosis of ovarian masses. Radiographics. 26 (5): 1431-48. doi:10.1148/rg.265045206 - Pubmed citation
- 13. Levine D, Brown DL, Andreotti RF et-al. Management of asymptomatic ovarian and other adnexal cysts imaged at US: Society of Radiologists in Ultrasound Consensus Conference Statement. Radiology. 2010;256 (3): 943-54. doi:10.1148/radiol.10100213 - Pubmed citation
- 14. Rezvani M, Shaaban AM. Fallopian tube disease in the nonpregnant patient. Radiographics. 31 (2): 527-48. doi:10.1148/rg.312105090 - Pubmed citation
- 15. Andreotti RF, Timmerman D, Strachowski LM, Froyman W, Benacerraf BR, Bennett GL, Bourne T, Brown DL, Coleman BG, Frates MC, Goldstein SR, Hamper UM, Horrow MM, Hernanz-Schulman M, Reinhold C, Rose SL, Whitcomb BP, Wolfman WL, Glanc P. O-RADS US Risk Stratification and Management System: A Consensus Guideline from the ACR Ovarian-Adnexal Reporting and Data System Committee. (2020) Radiology. 294 (1): 168-185. doi:10.1148/radiol.2019191150 - Pubmed
- 16. Patel MD, Ascher SM, Horrow MM, Pickhardt PJ, Poder L, Goldman M, Berland LL, Pandharipande PV, Maturen KE. Management of Incidental Adnexal Findings on CT and MRI: A White Paper of the ACR Incidental Findings Committee. (2020) Journal of the American College of Radiology : JACR. 17 (2): 248-254. doi:10.1016/j.jacr.2019.10.008 - Pubmed
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