Radiology case: Ovarian torsion

Findings: Figures 1 through 5 are axial images of a CT scan performed with contrast. The examination demonstrates a RIGHT pelvic mass which is inhomogeneous. There are areas of focal decreased density peripherally with a more focal central low density also demonstrated. NO free fluid.

Figures 6 through 8 are ultrasound studies of the same patient. Figure 6 demonstrates a mass with peripheral areas of decreased echogenicity. Figures 7 and 8 are Doppler studies which demonstrate minimal Doppler flow within the tissues around the margins of the mass but NO evidence of Doppler flow within the mass.

Click “read the rest of the entry” below to see more images and more information.



Diagnosis: Ovarian torsion. 

Etiology in incidence: 1) Greater than 75% of patients are diagnosed between the ages of 20 and 39 years of age. 2) This is slightly more commonly seen during pregnancy and almost 1 in 4 patients are pregnant at the time of diagnosis; Torsion can recur and is seen in up to 20% of patients who are pregnant and up to approximately 10% of nonpregnant patients. 3) The most common presentation is sudden severe pain in the pelvis. This may be associated with more generalized lower abdominal symptoms. Systemic symptoms including nausea and vomiting may also be present. Fever may also be seen.  4) Torsion is slightly more commonly seen on the RIGHT than the LEFT. 5) Greater than 50-60% of cases will be associated with a mass or cyst. These are typically greater than 4-6 centimeters in size. Because of their incidence in this age group, dermoid/teratoma tumors are the most common solid mass. 6) Patients with tubal ligation are also increased risk. Other pelvic surgeries also increase risk of torsion likely secondary to adhesions. 7) Less than 20% of cases present in the pediatric age group. Torsion has been diagnosed in children as young as 2 years old. 

CT: The inciting factor, whether large cyst or dermoid/teratoma will be demonstrated. In the absence of these abnormalities, the ovary is large with multiple focal cysts/follicles in the periphery. Centrally, there may be decreased density which may represent more prominent ischemia or central infarction; Free fluid and/or bloody fluid may be seen in the cul-de-sac or adnexa; Twisted/thickened fallopian tube may be seen. 

Ultrasound: Real time: Similar findings as that demonstrated with CT. Doppler: Doppler analysis can demonstrate NO or minimal flow within the torsed ovary. Because of additional vascularity to the adnexa, complete lack of flow is much less common than moderately or significantly decreased flow. A normal Doppler can also be seen in the presence of torsion and a normal Doppler does not exclude the possibility of torsion. Peripheral increase in Doppler flow is frequently seen. 

Differential diagnosis: 1) Appendicitis. 2) Diverticulitis. 3) Ureteral stones. 4) Perforated viscus. 5) Ectopic pregnancy. 6) Bowel obstruction. 7) Pelvic inflammatory disease and/or tubo-ovarian abscess and/or ovarian cysts.

Treatment/Prognosis: 1) There is an increased incidence of delayed diagnosis due to the broad differential diagnosis in these patients. Surgery and detorsion is frequently unsuccessful in ovarian salvage in adults with results slightly better in pediatric age patient. 2) Intervention is typically performed with laparoscopy. Detorsion of the ovary is performed. Oophoropexy is the procedure used to secure the ovary and prevent recurrence. 3) Death, as reported in the literature, is extremely rarely associated with torsion. Complications such as adhesions, chronic pain and infertility are more common. Infection, peritonitis and sepsis are also uncommon.


This entry was posted in Interesting Cases and tagged , . Bookmark the permalink.