Author Of 1 Presentation
P0723 - Internuclear Ophthalmoplegia Characterizes Multiple Sclerosis Rather Than Neuromyelitis Optica Spectrum Disease (ID 1542)
Abstract
Background
Neuromyelitis optica spectrum disease (NMOSD) and multiple sclerosis (MS) share clinical presentations including brainstem syndromes. Internuclear ophthalmoplegia (INO) is characterized by paresis of ipsilateral eye adduction in horizontal gaze. It usually corresponds to a lesion in the medial longitudinal fasciculus (MLF) and is commonly seen in MS. However, it is unclear if INO is as common in NMOSD.
Objectives
To determine the comparative prevalence of INO in patients with NMOSD and MS and compare clinical features of both disease processes.
Methods
This was a retrospective study of patients who have an established diagnosis of NMOSD and MS and visited both neuro-ophthalmology and MS clinics between 2015 and 2020. We used ICD10 billing codes for MS (G35) and NMOSD (G36) and patients were identified as having an INO if documented at any time during follow up. Logistic regression was used to evaluate the likelihood of developing an INO for NMO vs. MS patients. Multivariable analysis was adjusted for age, race, gender, and length of follow up.
Results
259 patients (70 NMOSD, 180 MS) were analyzed. Age range was 21 to 79 years with a mean age of 36.2 (SD+ 13.6 years) and mean disease duration of 1.8 years (SD + 4.6 years). Mean follow-up was 9.69 + 8.3 years. Most of the NMOSD patients were seropositive for AQP4 antibody (67.1%, n=47) followed by MOG antibody (17.1%, n=12). The overall frequency of INO in NMOSD was 1.4% (n=1) compared to 16% (n=30) in MS. Adjusted analysis showed that NMOSD patients were 9 times (OR: 0.112, 95% CI: 0.014-0.902, p=0.04) less likely to develop an INO compared to those with MS.
Conclusions
Our results show that NMOSD patients are less likely to develop an INO than MS patients at any point during their disease course. This suggests that INO and consequently MLF lesions are less common in NMOSD. Clinical implications lie in differentiation of NMOSD from MS and earlier pursuit of appropriate therapy.