Excludes1 pair
H49- vs H49.4-
H49 and H49.4 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on H49.4
Kearns-Sayre syndrome (H49.81-)
H49.4
Progressive external ophthalmoplegia
Not billable
- Chapter 7
- Diseases of the eye and adnexa
- Section
- H49-H52
Indexed under
- Ophthalmoplegia › external › progressive
- Strabismus › paralytic › ophthalmoplegia › progressive
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027