2006 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Nervous System And Sense Organs 320-389 > Other Disorders Of The Central Nervous System 340-349 > 2006 ICD-9-CM Diagnosis 346 Migraine View the most recent version of ICD-9-CM 346 A subtype of vascular headaches characterized by periodic unilateral pulsatile headaches which begin in childhood, adolescence, or early adult life and recur with diminishing frequency during advancing years. The two major subtypes are CLASSIC MIGRAINE (i.e., migraine with aura) and COMMON MIGRAINE (i.e., migraine without aura). Migrainous episodes may be associated with alterations in cerebral blood flow. 346 is a non-specific code that cannot be used to specify a diagnosis