Bilateral optic disc swelling; is a CT scan necessary?

A 47 year old man sustained a head injury after tripping. He presented to the accident and emergency department next morning where head x ray revealed no fractures. However, the casualty doctor found bilateral blurred optic disc margins on ophthalmoscopy. Although his head injury was classed as non-serious, an urgent computed tomography scan was ordered and an ophthalmic opinion sought. After detailed retinal examination, the ophthalmologist made a diagnosis of bilateral optic nerve head drusen (ONHD), which was confirmed by a B-scan ultrasound. The patient was advised not to drive (due to constricted visual fields associated with ONHD) and to inform his siblings of his condition so they could also be assessed. In cases of apparent optic disc swellings, it is essential to distinguish between true and pseudo-papillo-oedema to avoid subjecting patients to unnecessary neuroimaging procedures and associated exposure to radiation.