Amplitude of Accommodation in Patients with Multiple Sclerosis

ABSTRACT

Purpose: To evaluate the effect of multiple sclerosis (MS) on the amplitude of accommodation (AA) and retinal nerve fiber layer (RNFL) thickness.

Materials and Methods: A total of 25 MS patients with visual-evoked potential (VEP) abnormalities (MS/+VEP Group), 25 MS patients without VEP abnormalities (MS/-VEP Group), and 25 controls (Control Group) were enrolled. Only findings from the right eye of the participants were included in the analysis. Each participant underwent a pattern-reversal visual-evoked potential (PVEP) recording, an RNFL thickness analysis by optic coherence tomography (OCT) in all quadrants, and a measurement of amplitude of accommodation (AA) with minus lens technique. The AA and the RNFL thickness were compared between the groups.

Results: The mean age and sex distributions did not differ significantly across the groups (p= .788, p= .906, respectively). The mean AA was 5.36 ± 0.7 D in MS/+VEP group, 6.06 ± 1.4 D in MS/-VEP group, and 6.4 ± 0.9 D in control group (p= .002). The difference in the mean AA values between MS/+VEP and control groups were significant (p = .002). AA was significantly correlated with age, P100 latency and amplitude values in MS/+VEP group (r = −0.832, p < .001; r = −0.596, p = .002 and r = 0.498, p = .011, respectively). In a multivariable regression model, age and P100 latency were significant parameters for affecting AA in patients with MS (p < .001 and p = .001). In another multivariable regression model, age and average RNFL thickness were significant parameters for affecting AA in patients with MS (p < .001 and p = .010).

Conclusions: We found that the AA was lower in MS patients with VEP abnormalities compared to age-matched healthy individuals. P100 latency was a significant parameter for predicting AA in MS/+VEP group. These results suggest that MS patients with VEP abnormalities might experience presbyopia earlier in life than people without MS, probably due to the chronic demyelination of neural pathways.

KEYWORDS:

• Amplitude of accommodation
• visual evoked potential
• minus lens
• multiple sclerosis
• accommodation

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

No author has a financial or proprietary interest in any material or method mentioned.