H40-H42 — Glaucoma
ICD-10-CM codes H40-H42 cover glaucoma, within diseases of the eye and adnexa. The block holds 320 codes across 2 categories, of which 253 are billable and 67 are header codes that cannot be submitted on a claim. 237 of them (74%) require a 7th character.
The 7th character in H40-H42
A code in this block is not complete without its 7th character, and a missing one is a rejected claim rather than a denied one: the clearinghouse never passes it on. 237 of the 320 codes here take one.
- 0
- stage unspecified
- 1
- mild stage
- 2
- moderate stage
- 3
- severe stage
- 4
- indeterminate stage
What else to watch in H40-H42
- 138 codes are laterality-specific. They come in left and right pairs, and the pair is mutually exclusive on a single site: coding both without a bilateral code is a contradiction a scrubber should catch before the payer does.
- 247 codes are named in Medicare coverage policies. An LCD or NCD lists them as supporting medical necessity, or explicitly as not supporting it. Which applies depends on the MAC for your state.