[Correspondence] Optic nerve involvement in multiple sclerosis diagnosis – Authors’ reply

This text is the authors' reply to a letter concerning their previous position paper on multiple sclerosis diagnosis. The authors agree with the view that applying the "no better explanation" clause for optic nerve involvement can be challenging for non-specialists. This difficulty relates to supporting dissemination in space, which is crucial for establishing a multiple sclerosis diagnosis. They emphasize that the inappropriate application of diagnostic tools, such as optical coherence tomography (OCT) and visual evoked potentials (VEPs), carries significant risks. These risks can lead to unnecessary harm to patients. Harm can occur either by erroneously supporting a diagnosis of multiple sclerosis or, conversely, by erroneously failing to support this diagnosis.