H18.4Corneal degeneration
Code usage status
Primary diagnosis
May be used as the primary diagnosis
Apply only when it matches the confirmed diagnosis and the documented clinical record.
Specificity
Complete code in the classification
Use when the diagnosis matches and no exclusion applies.
- Chapter VII
- Diseases of the eye and adnexa
- Group H15-H22
- Disorders of sclera, cornea, iris and ciliary body
- Official Vietnamese name
- Thoái hóa giác mạc
- Additional WHO coding guidance
- Arcus senilis Band keratopathy Excl.: Mooren ulcer (H16.0)
Related H18 codes
H18
Other disorders of cornea
H18.0
Primary diagnosis candidate
Corneal pigmentations and deposits
H18.1
Primary diagnosis candidate
Bullous keratopathy
H18.2
Primary diagnosis candidate
Other corneal oedema
H18.3
Primary diagnosis candidate
Changes in corneal membranes
H18.5
Primary diagnosis candidate
Hereditary corneal dystrophies
H18.6
Primary diagnosis candidate
Keratoconus
H18.7
Primary diagnosis candidate
Other corneal deformities
H18.8
Primary diagnosis candidate
Other specified disorders of cornea
H18.9
Primary diagnosis candidate
Disorder of cornea, unspecified
Clinical record checklist
View coding guide →- Confirm that the code matches the final documented diagnosis.
- Use one primary-diagnosis code and record only relevant additional conditions.
- Review Ministry indicators, inclusions, exclusions and notes.
- Do not infer a diagnosis beyond the clinical record.
2026 regulatory basis
Indicators are taken from columns 24–29 of the classification accompanying Circular 06/2026/TT-BYT, cross-referenced with Decision 1849/QĐ-BYT and Official Dispatch 4059/BYT-BH.
