H46 refers to Optic neuritis, a group of conditions involving inflammation or damage to the optic nerve or visual pathways. These can be caused by autoimmune disorders, infections, trauma, or compressive lesions, and they often present with acute or progressive vision changes.

Symptoms

Sudden vision loss – Common in optic neuritis (H46)
Pain with eye movement – A classic sign of acute optic neuritis
Color vision deficiency – Especially red desaturation
Visual field defects – Seen in optic neuropathy or chiasmal lesions (H47)
Optic disc swelling or pallor – Observed on fundus examination
Headache or neurological symptoms – May accompany visual pathway involvement
Progressive or bilateral vision loss – Often seen in compressive or hereditary optic neuropathies

Diagnosis

Diagnosis of Optic neuritis includes detailed ophthalmic exam, visual acuity and color testing, visual field assessment, fundus exam, optical coherence tomography (OCT), and MRI of the orbits and brain. Blood tests or lumbar puncture may be needed to assess systemic or infectious causes.

ICD10 Code Usage

ICD10 code H46 is primarily used by ophthalmologists and neurologists. It supports diagnostic workups for unexplained vision loss, documents demyelinating diseases like multiple sclerosis, and justifies advanced imaging, corticosteroid therapy, or neurology referrals.

Related Codes

H47 – Other disorders of optic [2nd] nerve and visual pathways

FAQs

Q1: What is ICD10 code H46?
A: It refers to Optic neuritis, involving inflammatory, ischemic, compressive, or degenerative damage to the optic nerve or visual pathways.

Q2: Is optic neuritis reversible?
A: Often yes—many patients recover vision partially or completely within weeks, especially with treatment.

Q3: What are common causes?
A: Autoimmune diseases (like MS), infections, ischemia, trauma, or hereditary optic neuropathies.

Q4: How is it treated?
A: High-dose IV steroids for optic neuritis; surgery or systemic therapy for compressive or ischemic causes.

Q5: Who manages these conditions?
A: Neurologists, ophthalmologists, and sometimes neuro-ophthalmologists or neurosurgeons.

Conclusion

ICD10 code H46 enables timely identification and management of Optic neuritis, helping clinicians prevent permanent vision loss through early intervention, imaging, and systemic evaluation.