Abstract
Purpose :
MS associated visual function loss contributes to disability. However, with the advent of OCT technology recent research efforts have focused on structural ophthalmic measures. Additionally, the relapsing remitting MS (RRMS) phase has been the focus of study. This study aims to compare visual function and structural retinal changes between different MS phases.
Methods :
Patients with stable RRMS and secondary progressive (SPMS) were prospectively recruited from a tertiary care academic medical center. Best corrected visual acuity (BCVA) was assessed per the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol. Low contrast visual acuity (LCVA) was evaluated using a 1.25% Low Contrast Sloan Letter Chart. Thickness of the macula ganglion cell complex (GCC) and peripapillary retina nerve fiber layer (RNFL) were measured from OCT scans (Avanti, Optovue). Generalized Estimating Equation (GEE) models adjusted for age and within subject correlation were used to compare RRMS and SPMS eyes, and to assess relationships between function and structure. Eyes with a history of optic neuritis were not included in analysis.
Results :
32 eyes (20 RRMS, 12 SPMS) without a history of optic neuritis from 18 participants (15 Female, 3 Male, 50.25+/-14.60 years old) were studied. SPMS subjects were older than RRMS subjects. When adjusted for age, BCVA and LCVA letter scores were lower in SPMS subjects compared to RRMS subjects by 2.5 and 8.3 letters respectively (p=0.250, p=0.032). RNFL, and GCC in fovea, parafovea and perifovea regions were thinner in SPMS (p=0.374, p=0.067, p=0.020, p=0.005). Adjusted for age, BCVA was associated with parafoveal GCC thickness (p=0.021), whereas LCVA was associated with RNFL thickness (p=0.015).
Conclusions :
SPMS eyes had reduced visual function, and thinner retinal ganglion cell layers than RRMS eyes, keeping with its current characterization as a more advanced phase of MS. Similar to prior studies in RRMS, there was a relationship between visual function and retina structural in our combined sample. Further research is needed to determine how best to utilize visual function and ophthalmic structure measures for identifying MS progression.
This is a 2020 ARVO Annual Meeting abstract.