Imaging the retinal architecture, and the retinal nerve fiber layer in particular, appears to correlate with clinical phenotype. "We observed lower [retinal nerve fiber layer] values in progressive MS subtypes relative to patients with less advanced disease," the study authors said.
The investigators noted worse visual function among patients with MS and optic neuropathy (ON), a common comorbidity of the systemic disease. That finding may be due to repeat inflammatory events that damage axonal visual pathways, according to the study.
Retinal-nerve fiber layer (RNFL) values were reduced in eyes with primary progressive MS (94.3 µm), relapsing-remitting MS (99.6 µm) and secondary progressive MS (84.7 µm) compared with eyes of patients with optic neuropathy as a clinically isolated syndrome (105.7 µm).
Because patients with secondary progressive MS are known to have a longer duration of disease, they may also have greater risk for recurrent optic neuropathy, which may, in turn, lead to continual thinning of the RNFL, the investigators said.
According to the study, a simple linear regression model showed that visual field sensitivity decreased 5.8 dB with every 10 µm regression in RNFL value.
Posted by Lee Mather
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