Added value of the gray-scale whirlpool sign in the diagnosis of adnexal torsion

Objective: Adnexal torsion is a common gynecologic emergency affecting females of all ages. Expedient diagnosis and treatment are important, particularly in young fertile patients to preserve ovarian viability. Classical parameters for the clinical and sonographic diagnosis of adnexal torsion have very high false-positive rates, approaching 50%. The sonographic 'whirlpool' sign has been shown to be effective for visualizing the torsed part in the prenatal diagnosis of malrotation of the midgut with volvulus, as well as scrotal and ovarian torsion. We aimed to evaluate the efficacy of the whirlpool sign in the diagnosis of torsion, as compared to a protocol based on 'classic' sonographic signs of torsion alone. Methods This was a retrospective chart review. Files of all patients who underwent laparoscopy for suspected torsion at our center between January 2006 and May 2009 were extracted and reviewed. Ultrasound reports were retrieved from our computerized database. Patients were assigned to the study group if the whirlpool sign had been investigated during pre-procedural evaluation or to the control group if only the standard protocol had been applied. Results Eighty women were referred for laparoscopy for suspected adnexal torsion during the study period. In 22 women the ultrasound investigation had included the whirlpool sign (study group) while 58 had been examined by the standard protocol (control group). Twenty women in the study group had a positive whirlpool sign on ultrasound, 18 of whom (90.0%) had confirmed torsion on laparoscopy. In the control group 32 of 58 (55.2%) women had confirmed torsion on laparoscopy. Conclusion The addition of the sonographic whirlpool sign to the preoperative sonographic evaluation of patients with suspected torsion appears to improve the rate of true-positive diagnoses as confirmed by laparoscopy.