Introduction: Clinical Application of OCT in Multiple Sclerosis

Abstract

Optical coherence tomography (OCT) offers a unique and novel technology to quantify the extent of neurodegenerative changes in individual patients with multiple sclerosis (MS). The retinal nerve fiber layer (RNFL) consists of nonmyelinated axons; therefore any change to RNFL integrity can be supposed to reflect thinning or loss of its axons. Similarly, a loss of ganglion cell layer thickness reflects a loss of primary neurons (i.e., ganglion cells). Clinically, visual impairment is common in MS with 20–30 % of patients presenting with multiple sclerosis associated optic neuritis (MSON) as a primary symptom. Recent evidence from histopathology studies suggests that primary retinal pathology involves retinal axons and neurons despite the absence of myelin—the major target of the autoimmune response in MS. Based on patients’ perceptions, visual function is the second highest-ranked bodily function next to ambulation in both early and late disease stages.