CT in the diagnosis of adnexal torsion: a retrospective study

Ultrasonography (USG) is the first and best modality for diagnosis of the adnexal torsion. But frequently in clinical practice, computed tomography (CT) scan becomes the first acquired modality as adnexal torsion mimics other non-gynaecological conditions. This retrospective study evaluated the diagnostic performance of CT as a modality in adnexal torsion. Thirty cases of surgically proven adnexal torsion with preoperative CT scans were included. Changes in the ovary, fallopian tube, uterine axis and other features were documented and analysed. At least one positive CT sign was seen in all 30 adnexal torsion patients. Twisted pedicle was seen in 100% cases. Peripherally displaced follicles in 57.1%, associated mass in 93.3%, ovarian hyperdensity in 46.4%, hydrosalpinx in 46.7%, change in uterine axis in 43.4% and ascites in 73.3%. CT of the pelvis can diagnose ovarian torsion when the described signs are carefully looked for.Impact statementWhat is already known on this subject? Adnexal torsion is an surgical emergency where delayed diagnosis may reduce the ovarian salvageability rate. USG has been a trusted modality for imaging the adnexa and associated pathologies such as torsion. It is a general assumption that CT is not an apt modality for diagnosis of torsion.What the results of this study add? The results of this study emphasise that CT can be used to diagnose adnexal torsion when the signs described are carefully looked for. A normal appearing ovary on CT can rule out torsion as at least one sign will be positive in such cases.What the implications are of these findings for clinical practice and/or further research? As adnexal torsion clinically mimics non-gynaecological conditions such as ureteric colic, appendicitis, etc. where CT is the initial and only available modality, applying the results of our study can aid in diagnosis of adnexal torsion on CT itself, prompting immediate surgical referral and thereby reducing the delay by not acquiring or confirming by another modality such as USG.