Answer for BIR CoW 04 Sep 2022
Ovarian torsion
Findings
Bilateral enlarged polycystic ovaries. Enlarged right ovary with edematous stroma and peripherally placed cysts with thin rim of hemorrhage around the right ovary and follicles with no enhancement on contrast - Suggestive of torsion of right ovary. Mild free fluid in the pelvic peritoneal cavity.
Discussion
Ovarian torsion occurs when the ovary and its vascular pedicle twist on its axis. Initially, there is obstruction to venous and lymphatic outflow thereby resulting in congestion. When left unattended, there is compromise of the arterial supply amounting to ischemia and hemorrhagic infarction . Prompt recognition of torsion in imaging and immediate restoration of blood supply is therefore vital to preserve the ovarian function. Predisposing factors include anatomical factors such as redundant mesosalpinx(rare) but most commonly encountered in enlarged ovaries as in cysts, ovarian tumours, ovarian hyperstimulation syndrome, corpus luteal cysts in pregnant females. Sonographic findings include enlargement of the ovary ( single dimension > 4cm or volume >20ml), peripherally arranged follicles with heterogenous/ ground glass stroma. Abnormal twisting of the fallopian tubes though not always seen is a useful finding. Free fluid might be present in cases with infarction Doppler abnormalities need not always be present to confirm the diagnosis. Twisted vascular pedicle and absent venous flow with reversal or absent diastolic flow in the arteries may be seen. MRI findings include enlarged ovary with peripherally arranged and hyperintensity of the central ovarian stroma in T2 weighted images. Adnexal thickening might be present. Blooming in gradient images might be seen in the central ovarian stroma in cases with hemorrhagic infarction. Absence of enhancement of the torsed ovary does not occur until late due to the preserved arterial supply. Twisted pedicle when present is a characteristic finding.
References:
Adnexal Torsion: Review of Radiologic Appearances M. Taufiq Dawood, Mitesh Naik, Nishat Bharwani, Siham A. Sudderuddin, Andrea G. Rockall, and Victoria R. Stewart RadioGraphics 2021 41:2, 609-624 Pearls and Pitfalls in Diagnosis of Ovarian Torsion Hannah C. Chang, Shweta Bhatt, and Vikram S. Dogra RadioGraphics 2008 28:5, 1355-1368 Ovarian Torsion: Diagnostic Features on CT and MRI With Pathologic Correlation Shauna Duigenan, Esther Oliva, and Susanna I. Lee American Journal of Roentgenology 2012 198:2, W122-W131
Findings
Bilateral enlarged polycystic ovaries. Enlarged right ovary with edematous stroma and peripherally placed cysts with thin rim of hemorrhage around the right ovary and follicles with no enhancement on contrast - Suggestive of torsion of right ovary. Mild free fluid in the pelvic peritoneal cavity.
Discussion
Ovarian torsion occurs when the ovary and its vascular pedicle twist on its axis. Initially, there is obstruction to venous and lymphatic outflow thereby resulting in congestion. When left unattended, there is compromise of the arterial supply amounting to ischemia and hemorrhagic infarction . Prompt recognition of torsion in imaging and immediate restoration of blood supply is therefore vital to preserve the ovarian function. Predisposing factors include anatomical factors such as redundant mesosalpinx(rare) but most commonly encountered in enlarged ovaries as in cysts, ovarian tumours, ovarian hyperstimulation syndrome, corpus luteal cysts in pregnant females. Sonographic findings include enlargement of the ovary ( single dimension > 4cm or volume >20ml), peripherally arranged follicles with heterogenous/ ground glass stroma. Abnormal twisting of the fallopian tubes though not always seen is a useful finding. Free fluid might be present in cases with infarction Doppler abnormalities need not always be present to confirm the diagnosis. Twisted vascular pedicle and absent venous flow with reversal or absent diastolic flow in the arteries may be seen. MRI findings include enlarged ovary with peripherally arranged and hyperintensity of the central ovarian stroma in T2 weighted images. Adnexal thickening might be present. Blooming in gradient images might be seen in the central ovarian stroma in cases with hemorrhagic infarction. Absence of enhancement of the torsed ovary does not occur until late due to the preserved arterial supply. Twisted pedicle when present is a characteristic finding.
References:
Adnexal Torsion: Review of Radiologic Appearances M. Taufiq Dawood, Mitesh Naik, Nishat Bharwani, Siham A. Sudderuddin, Andrea G. Rockall, and Victoria R. Stewart RadioGraphics 2021 41:2, 609-624 Pearls and Pitfalls in Diagnosis of Ovarian Torsion Hannah C. Chang, Shweta Bhatt, and Vikram S. Dogra RadioGraphics 2008 28:5, 1355-1368 Ovarian Torsion: Diagnostic Features on CT and MRI With Pathologic Correlation Shauna Duigenan, Esther Oliva, and Susanna I. Lee American Journal of Roentgenology 2012 198:2, W122-W131
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!