Evaluation of the Relationship Between Optic Nerve Diameter and Optic Nerve Sheath Diameter Measured by Transorbital Sonography With Clinical, Radiological, and Electrophysiological Parameters in Multiple Sclerosis Patients

The primary aim of this study is to evaluate the reliability of optic nerve diameter (OND) and optic nerve sheath diameter (ONSD) measurements made with transorbital sonography (TOS) and magnetic resonance imaging (MRI) in patient groups that may progress with subclinical optic atrophy over time, such as those with multiple sclerosis (MS). The secondary aims of this study are to compare the relationship of TOS with visual evoked potentials (VEP) and optical coherence tomography (OCT) parameters used in the assessment of the afferent visual pathway in MS and its clinical subtypes and to evaluate the potential of TOS as a diagnostic and monitoring tool for detecting optic nerve atrophy, subclinical axonal loss, and clinical disability in MS.