Convert ICD-10 Code G44.001 to ICD-9

Source ICD-10 Code		Target ICD-9 Code
G44.001 Cluster headache syndrome, unspecified, intractable		339.00 Cluster headache syn NOS
Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

ICD-10 to ICD-9 crosswalk for code G44.001 - cluster headache syndrome, unspecified, intractable based on the most recent General Equivalence Mappings (GEMS) information.