New developments in the treatment of optic neuritis

Abstract

Acute optic neuritis (ON) has various etiologies. The most common presentation is inflammatory, demyelinating, idiopathic, or "typical" ON, which may be associated with multiple sclerosis. This must be differentiated from "atypical" causes of ON, which differ in their clinical presentation, natural history, management, and prognosis. Clinical "red flags" for an atypical cause of ON include absent or persistent pain, exudates and hemorrhages on fundoscopy, very severe, bilateral, or progressive visual loss, and failure to recover. In typical ON, steroids shorten the duration of the attack, but do not influence visual outcome. This is in contrast to atypical ON associated with conditions such as sarcoidosis and neuromyelitis optica, which require aggressive immunosuppression and sometimes plasma exchange. The visual prognosis of typical ON is generally good. The prognosis in atypical ON is more variable. New developments aimed at designing better treatments for patients who fail to recover are discussed, focusing on recent research elucidating mechanisms of damage and recovery in ON. Future therapeutic directions may include enhancing repair processes, such as remyelination or adaptive neuroplasticity, or alternative methods of immunomodulation. Pilot studies investigating the safety and proof-ofprinciple of stem cell treatment are currently underway.

Incidence and Causes of Overdiagnosis of Optic Neuritis

“…Inaccurate/misinterpreted examination 7 (10) Failure in weighing examination findings 6 (8) Error in diagnostic testing 11 (15) Failure to order necessary test 2 otherwise normal. Optic discs with an anomalous appearance may mimic optic disc edema and lead to an erroneous diagnosis of optic neuritis.…”

“…O ptic neuritis is an acute inflammatory demyelinating optic neuropathy that can occur in isolation or herald other underlying diseases, such as multiple sclerosis (MS) or neuromyelitis optica. [1][2][3][4][5][6][7][8] Optic neuritis classically presents with acute to subacute central visual loss, pain with eye movements, and dyschromatopsia. Diagnosis is based on presenting symptoms, time course, and examination findings consistent with optic neuropathy, such as abnormal visual acuity, visual fields, color vision, or the presence of a new relative afferent pupillary defect (APD).…”

“…Diagnosis is based on presenting symptoms, time course, and examination findings consistent with optic neuropathy, such as abnormal visual acuity, visual fields, color vision, or the presence of a new relative afferent pupillary defect (APD). [1][2][3][4][5][6][7][8] Diagnosis may be supported by neuroimaging studies, such as magnetic resonance imaging (MRI). [1][2][3][4][5] Optic disc swelling may be present but is not mandatory for diagnosis; the inflammation is retrobulbar in two-thirds of patients.…”

“…[1][2][3][4][5] Optic disc swelling may be present but is not mandatory for diagnosis; the inflammation is retrobulbar in two-thirds of patients. 1,3,[6][7][8] Treatment with intravenous corticosteroids 2,9 or megadose oral corticosteroids [10][11][12] hastens visual recovery, and further diagnostic investigation with MRI or lumbar puncture is often performed to stratify the risk of progression to MS. [2][3][4][5][6][7][8]13 In many cases, diagnostic error does not reflect gaps in knowledge but rather reasoning errors or cognitive biases, such as premature closure and anchoring bias. [14][15][16][17][18][19][20] One prior study 14 reported up to 74% of diagnostic errors may be caused by cognitive factors.…”

Unilateral Acute Idiopathic Optic Neuritis With Superior Altitudinal Visual Field Defect as a Presenting Feature

“…Recovery of visual function in acute optic neuritis is known to occur within the first month of the onset. In the ONTT, 79% of the participants had started to improve by three weeks and 93% by five weeks [9]. In our patient, four days after the completion of the course of a high dose of intravenous methylprednisolone, altitudinal field defect disappeared completely.…”