Neonatal ovarian cysts: role of sonography in diagnosing torsion

The purpose of this case series was to determine the sonographic features of neonatal ovarian torsion.

Seven surgically proven cases of neonatal ovarian cysts were included in this retrospective study. The patients were divided into 2 groups, torsion and non-torsion. These 7 patients were evaluated for the clinical presentation, sonographic features, surgical and pathological findings. The findings on follow-up sonography after surgery were also noted.

The sonographic appearance was variable. Of the 4 cases with torsion, 2 lesions had internal echoes with 'fi sh-net appearance'. The other 2 lesions were predominantly cystic on the sonography with internal echoes and echogenic nodule. A calcific focus was present in 1 of these echogenic nodules. One of the cysts had fluid-fluid level. In the non-torsion group, only 1 lesion had mixed echogenic appearance. The other 2 lesions were cystic with low level internal echoes in 1 of the cysts. The surgical procedure performed in the torsion group was salpingo-oophorectomy in 2 patients and oophorectomy in 1 patient. In 1 patient, cystectomy was attempted without success. In the non-torsion group, only cystectomy was performed with preservation of normal ovaries, which was confirmed on follow-up sonography.

The sonographic features of cysts with 'fish-net appearance', fluid-debris level and cysts with echogenic nodule favour torsion. The former sign has so far not been described as a sonographic predictor for neonatal ovarian torsion.