Pediatric whole body MRI detects causative ovarian teratoma in opsoclonus myoclonus syndrome.

Opsoclonus Myoclonus Syndrome (OMS, or Opsoclonus Myoclonus Ataxia) is a rare condition that presents with saccadic movements of the eyes, cerebellar ataxia, and choreiform movements of the limbs. While previous reports have described the use of ultrasound, CT, FDG-PET and traditional focused MRI for localization of OMS-associated masses, whole body MRI has not previously been reported for this purpose. Here we describe a 16-year-old patient who exhibited OMS and underwent whole body MRI to rule out the more commonly associated neuroblastoma. An ovarian mass was discovered, resected, and pathology confirmed benign teratoma - there was subsequent resolution of symptoms after complete surgical resection. Whole body MRI should be considered in pediatric cases of OMS due to the paraneoplastic nature of the disease with associated tumor, high sensitivity of disease detection, lack of ionizing radiation, excellent tissue resolution and demonstrated effectiveness in pediatric imaging.