ICD-10 Code H40.50X2 representing "Glaucoma sec to oth eye disord, unsp eye, moderate stage" can be backward-mapped to its ICD-9 equivalent 365.59: "Glaucoma w lens dis NEC". This conversion was generated using the latest General Equivalence Mappings (GEMs). While these mappings provide a standardized reference, not all ICD-10 codes have an exact ICD-9 match. Review the table below carefully and consider the clinical context when interpreting the mapped codes.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glaucoma w lens dis NEC
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glauc w ocular dis NOS
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glauc w pupillary block
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glaucoma w tumor or cyst
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glaucoma w lens dis NEC
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glauc w ocular dis NOS
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glauc w pupillary block
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Glaucoma w tumor or cyst
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
ICD‑10 Code
Glaucoma sec to oth eye disord, unsp eye, moderate stage
ICD‑9 Code
Moderate stage glaucoma
Approximate Flag – This ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option and may not fully capture the original diagnosis.
The General Equivalence Mappings tool is a standardized crossover resource developed by the Centers for Medicare & Medicaid Services (CMS) and the National Center for Health Statistics (NCHS). It was created to help healthcare providers, coders, payers, and software vendors accurately transition between ICD-9 and ICD-10 diagnosis codes.
This ICD-10 to ICD-9 crosswalk tool supports both forward and backward mapping, making it valuable for converting legacy data, conducting audits, updating medical coding systems, and ensuring compliance with ICD-10 standards. GEMs are especially helpful when analyzing historical claims, aligning reimbursement logic, or migrating between systems.
Because not all ICD codes have a direct match, users should interpret each mapping carefully. Some ICD-10 to ICD-9 conversions may require clinical judgment or additional documentation to ensure coding accuracy.
Not all ICD-10 to ICD-9 code conversions result in a single, exact match. In some cases, an ICD-10 code may map to multiple ICD-9 codes, especially when the original diagnosis requires more than one code to fully capture its meaning in the older coding system.
