Neuromyelitis optica [Devic]

This code identifies Neuromyelitis Optica Spectrum Disorder (NMOSD), an autoimmune inflammatory disorder of the central nervous system primarily affecting the optic nerves and spinal cord. It is characterized by severe, recurrent attacks of optic neuritis and transverse myelitis, often leading to significant disability.

Assign this code when documentation clearly indicates a diagnosis of Neuromyelitis Optica (Devic's disease) or Neuromyelitis Optica Spectrum Disorder (NMOSD). Supporting documentation typically includes neurological examination findings, MRI results showing characteristic lesions, and positive aquaporin-4 (AQP4) antibody testing.

• Differentiate carefully from multiple sclerosis (MS), as NMOSD has distinct diagnostic criteria and treatment approaches.
• Remember the Excludes1 note for optic neuritis NOS (H46); these conditions should never be coded together.
• Look for specific mention of "Devic's disease" or "Neuromyelitis Optica Spectrum Disorder" in the provider's diagnostic statement.