Chronic relapsing inflammatory optic neuropathy [Crion]

ABSTRACT

This newly recognized entity named chronic relapsing inflammatory optic neuropathy [CRION] is a form of inflammatory optic neuropathy which is frequently bilateral and often painful, and is characterized by relapses and remissions. There is no evidence of acquired demyelinating disorders and systemic collagen vascular or granulomatous diseases. To study the clinical features and response to treatment in patients with recurrent optic neuritis consistent with diagnosis of chronic relapsing inflammatory optic neuropathy [CRION]. Materials and. This is retrospective cross sectional study carried out at department of Neurology, King Edward Medical University, Lahore. Patients with history of recurrent episodes of acute or subacute loss of vision accompanied by pain consistent with optic neuritis, unilateral or bilateral, but, without evidence of an acquired demyelinating disorders, systemic collagen vascular orgranulomatous diseases were included in the study. The response to various treatments was also analyzed.A total of 4 patients were identified. All were females with mean age at presentation 35.50+8.10 years and mean age at onset of first episode was 28+10.92 years. Mean duration of illness was 7. 25 + 4.57 years. The number of episodes varied from 3-6 [mean 4+1.41episodes]. Mean episodes of right optic neuritis were 2.25+0.95 and left side 1.50+ 0.57. Only one patient had an episode of simultaneous bilateral optic neuritis. All patients experienced severe pain with loss of vision to finger counting at less than one meter. MRI brains, detailed vasculitis profile, serum angiotensin converting enzyme [ACE] inhibitor level, and X-ray chests were normal in all patients. The CSF for oligoclonal band was also negative. All patients received pulse therapy with methylprednisolone 1 gm daily for three days followed by two weeks oral taper. Most patients improved after first episode but there was partial recovery after the second and subsequent episodes. Only one patient had complete loss of vision in one eye. Two patients received long term oral steroids and azathioprine with prevention of further relapses. One patient received beta interferonwith complete remission so far. One patient received cyclosporine and oral steroids with remission for 6 years but subsequently relapsed after immunotherapy was discontinued. Chronic relapsing inflammatory optic neuropathy [CRION] should be considered in patients with history of recurrent optic neuritis after exclusion of acquired demyelinating disorders, and systemic collagen vascular or granulomatous diseases