How accurate are ct scans? is it possible that the doctor could mistake my ovary for something else in a ct scan? i had one done and he said the ct scan showed a low density structure in my proximal sigmoid colon as well as a mass in my right pelvis.

Yes, : Yes, an enlarged ovary could be mistaken for a mass in the pelvis. An ovarian cyst could be described as a low density structure which could be near the sigmoid colon, but without seeing the images it is impossible to know whether this is the case. The best way to evaluate the ovaries is with transpelvic and/or transvaginal ultrasound. It may be helpful to have your doctor discuss the findings with the radiologist. The radiologist should be able to give some recommendations as to whether further evaluation with imaging such as pelvic ultrasound would be helpful or whether you should be referred directly to a surgical specialist.

Doctors: Radiologist is most likely correct describing your abnormalities. Ordering physician reads ct scan too. Talk to him.

Moderately: Ct scans are good at diagnosing large tumors and other common intra abdominal problems. Vaginal ultrasound is much better at visualizing the ovaries and the uterus.