Unspecified open-angle glaucoma, mild stage

This code signifies a diagnosis of open-angle glaucoma where the specific type (e.g., primary, secondary) is not documented, and the disease progression is classified as mild. It indicates a chronic optic neuropathy characterized by characteristic optic nerve damage and visual field loss, with intraocular pressure often elevated.

Apply this code when the physician's documentation clearly states "open-angle glaucoma" without further specification, and the staging indicates a "mild" stage based on visual field defects and optic nerve damage. This is appropriate when the provider has not specified the etiology of the open-angle glaucoma.

• Ensure documentation explicitly states "mild stage" for open-angle glaucoma; otherwise, an unspecified stage code may be more appropriate.
• Do not use this code if the type of open-angle glaucoma (e.g., primary, pigmentary, pseudoexfoliative) is specified; use a more specific code from the H40.1- series.
• Always sequence this code after any underlying systemic conditions contributing to secondary glaucoma, if applicable and documented.