Intraventricular silicone oil.

The authors report a case in which intravitreous silicone oil migrated into the ventricles. They note that intraventricular silicone oil can be misdiagnosed as intraventricular hemorrhage and neurosurgeons should be aware of this possibility. This 58-year-old woman with a history of Type II diabetic mellitus and retinal detachment (resulting from diabetic retinopathy), which had been treated with intravitreous silicone tamponade, presented with dizziness and headache approximately 10 years after the intravitreous silicone treatment. Over the next 6 years she underwent 2 non-contrast-enhanced brain CT studies and 1 MRI study for evaluation of her symptoms. On CT scan, extension of the intraocular silicone along the optic nerve was evident. Two hyperdense nodules were observed freely floating in the right lateral and fourth ventricles, remaining in the nondependent portion of ventricles in both supine and prone positions. On T2-weighted MRI, the left orbital content and the intraventricular nodules all demonstrated chemical shift artifacts typically associated with silicone. The imaging findings were characteristic for intraventricular silicone after silicone oil tamponade. The patient's dizziness and headache were treated symptomatically and she was followed up at the outpatient department. Migration of intravitreous silicone oil into the cerebral ventricles is a rare complication. Intraventricular silicone oil can mimic intraventricular hemorrhage. Radiographically, intraventricular silicone oil can be distinguished from hemorrhage as silicone oil tends to stay in the nondependent portion of the ventricle. Chemical shift artifacts on MRI may help establishing the diagnosis of intraventricular silicone oil. Currently, there is no consensus on surgical removal of intraventricular silicone oil, and in the majority of cases reported in the literature, the patients were asymptomatic.