FY2027 ICD-10-CM reference
H16.122: Filamentary keratitis, left eye
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Filamentary keratitis, left eye. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Instructional note
Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition
Source: H00-H59 (chapter, inherited).
Excludes2
certain conditions originating in the perinatal period (P04-P96)
Source: H00-H59 (chapter, inherited).
Excludes2
certain infectious and parasitic diseases (A00-B99)
Source: H00-H59 (chapter, inherited).
Excludes2
complications of pregnancy, childbirth and the puerperium (O00-O9A)
Source: H00-H59 (chapter, inherited).
Excludes2
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
Source: H00-H59 (chapter, inherited).
Excludes2
diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
Source: H00-H59 (chapter, inherited).
Excludes2
endocrine, nutritional and metabolic diseases (E00-E88)
Source: H00-H59 (chapter, inherited).
Excludes2
injury (trauma) of eye and orbit (S05.-)
Source: H00-H59 (chapter, inherited).
Excludes2
injury, poisoning and certain other consequences of external causes (S00-T88)
Source: H00-H59 (chapter, inherited).
Excludes2
neoplasms (C00-D49)
Source: H00-H59 (chapter, inherited).
Excludes2
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: H00-H59 (chapter, inherited).
Excludes2
syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)
Source: H00-H59 (chapter, inherited).
Compare the FY2027 additions, removals and billable-status changes
What does H16.122 mean in FY2027?
The official ICD-10-CM descriptor is Filamentary keratitis, left eye. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is H16.122 billable in FY2027?
The FY2027 order file marks H16.122 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does H16.122 map to an HCC?
H16.122 has no CMS-HCC V28 category in the CMS 2027 Initial ICD-10-CM Mappings (payment year 2027, 2026 dates of service). ESRD, RxHCC, PACE and HHS-HCC mappings are still pending verification for FY2027.
Source: CMS FY2027 ICD-10-CM order file. Read the FY2027 Official Guidelines.
Review the FY2026 April edition