Peripheral hypervascularity of the corpus luteum with ovarian edema (CLOE) may decrease false positive diagnoses of ovarian torsion

Pearls and Pitfalls in Imaging of Pelvic Adnexal Torsion: Seven Tips to Tell It's Twisted

Pelvic adnexal torsion is a collective term referring to twisting of an ovary, fallopian tube, or paraovarian cyst on its axis with varying degrees of vascular compromise. Although it is the fifth most common gynecologic emergency, the diagnosis is challenging and often missed due to symptoms, physical examination findings, and imaging features that are nonspecific. Delay in salvage surgery may lead to ovarian or tubal loss, dysfunction, and infertility. The tips shared herein are based on the authors' observations of key clinical and imaging features of torsion, with the intent of heightening radiologists' index of suspicion and diagnostic accuracy in a clear and memorable fashion. Clinically, severe acute pain with a known adnexal mass or of severity to elicit nausea or vomiting should raise concern. At imaging, features of ovarian edema are key to the diagnosis, including asymmetric ovarian enlargement, peripheralized follicles, adjacent free fluid, and foci of stromal hemorrhage. The converse finding of symmetric nonenlarged ovaries in a normal location with any imaging modality has a high negative predictive value for torsion, obviating the need for additional imaging. The whirlpool sign (twisted vascular pedicle), abnormal ovarian location, and uterine tilting are additional key imaging manifestations. The presence of color Doppler flow or contrast enhancement only suggests that an ovary is still viable and should not be used to exclude the diagnosis of torsion. In cases of isolated tubal or paraovarian cyst torsion, the ovaries may appear normal; therefore, recognition of this entity along with appreciation of several key imaging findings may assist with this difficult diagnosis. An invited commentary by Dighe is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

Is color Doppler ultrasonography reliable in diagnosing adnexal torsion? A large cohort analysis

INTRODUCTION

Color Doppler ultrasonography (CDU) is widely used to diagnose adnexal torsion (AT). However, its validity remains questionable due to its low sensitivity. Our study aimed to evaluate the accuracy of CDU for the preoperative diagnosis of AT.

MATERIAL AND METHODS

The electronic medical records of patients who were taken to the operating room with the diagnosis of suspected AT were reviewed. Patients having surgically/pathologically-proven AT were compared with patients who were found to have a different pathology at the time of surgery. CDU validity was assessed using a 2 × 2 table and compared with a diagnostic model that consists of the Doppler findings, patient's age, and previous surgical history.

RESULTS

AT was diagnosed correctly in 74.6% of cases. Absent Doppler flow was seen in only 18.6% of cases. Although its specificity and positive predictive value were high, CDU had very low sensitivity and negative predictive value. The combined diagnostic model exceeded CDU alone in terms of diagnostic accuracy.

CONCLUSIONS

The use of CDU alone is not a reliable modality to exclude AT. Absent Doppler flow is a sign of ovarian necrosis. Clinical correlation between CDU findings and the patient's symptoms makes the diagnosis of AT more timely and accurate.

Imaging of Postpartum/Peripartum Complications

There are various complications that can occur in the postpartum period, including pain, bleeding, and infection. These include complications related to cesarean section, postpartum hemorrhage and hematomas, bladder injury, torsion and uterine dehiscence, and rupture. It is important the radiologist is aware of these entities and the associated imaging features to help guide timely and appropriate management.