Purpose:
To analyze clinical data in a single center large series of patients with inflammatory optic neuropathy (ON) with or without associated multiple sclerosis (MS).
Methods:
We retrospectively reviewed the charts of 599 cases of inflammatory ON (400 females,199 males, mean age 37 yrs, mean follow-up 46 months) evaluated at Neuro-Ophthalmology Unit of San Raffaele Hospital from January 2002 to May 2011. Patients were divided in 7 groups according to etiology. Distribution of cases, demographic data, onset and final visual acuity (VA), spontaneous or eye movements related pain, optic nerve MRI findings, number of relapses, type of treatment, spontaneous or therapy related recovery were compared within the groups.
Results:
MS related ON (MS-ON) included 498 patients (83%), NMO 18 patients (3%), ON (in systemic autoimmune disease AON) 16 patients (3%), Isolated AON 19 patients (3%) ,Isolated Inflammatory Optic Neuropathy (ION) 11 patients (2%),Chronic Relapsing Inflammatory ON (CRION) 6 patients (1%), Unclassified inflammatory ON 31 patients (5%). Pain at onset was found between 30 and 50% with higher frequency in females. In the most of nonMS-ON (101 cases), MRI was negative in the acute phase. The average age at onset was higher in nonMS-ON, with later and atypical onset in males than females. Within nonMS-ON 31 cases were unclassified (30%).The greatest number of relapses was found in patients with an autoimmune etiology.Final VA equal to 20/20 was found in 277 patients with MS-ON (56%).Final VA less than 20/200 was found in 24 patients with MS-ON (9%) and in 40 patients with nonMS-ON (40%).
Conclusions:
The largest number of cases of inflammatory ON occurs in association with MS with a distribution ratio of patients of 5 to 1 compared to other etiology. Different clinical behaviors were found in different etiologic group of inflammatory ON. Final visual acuity, which is an impact parameter on patient’s quality of life, seems to be closely related to prompt and precise therapy. The high number of patients with unclassified inflammatory ON can be explained by the effect of a late or incorrect diagnosis. Hence the need for a specific etiological classification of inflammatory ON not related to MS, in order to establish early a targeted therapy that ensures the best visual prognosis.
Keywords: neuro-ophthalmology: optic nerve • neuro-ophthalmology: diagnosis