H18.4Corneal degeneration

H18.4 is the ICD-10-CM diagnosis code for corneal degeneration. It belongs to category H18 (other disorders of cornea), block H15-H22 (disorders of sclera, cornea, iris and ciliary body) and chapter 7 (diseases of the eye and adnexa). It is a header code, so it can't be reported by itself; one of its 8 subcodes must be used instead.

Within H18 (other disorders of cornea), H18.4 is specifically for corneal degeneration. Related codes cover corneal pigmentations and deposits (H18.0), bullous keratopathy (H18.1), other and unspecified corneal edema (H18.2), changes of corneal membranes (H18.3), hereditary corneal dystrophies (H18.5), Keratoconus (H18.6), other and unspecified corneal deformities (H18.7), other specified disorders of cornea (H18.8) and 1 more.

To report this condition, pick the subcode that matches the documentation: H18.40 (degeneration), H18.41 (senilis), H18.42 (keratopathy), H18.43 (degeneration), H18.44 (keratomalacia), H18.45 (degeneration), H18.46 (degeneration) and H18.49 (degeneration).

Don't report H18.4 together with the conditions in its Excludes1 note: Mooren's ulcer (H16.0-) and recurrent erosion of cornea (H18.83-).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.