ICHD classification and diagnosis of migraine are further subdivided. Overall ICHD-3 beta distinguishes 29 migraine subtypes. The following table outlines the main subtypes and their ICHD-1, -2, -3 beta and ICD-10 codes. Migraine without aura also referred to as a "common migraine", (previously known as "hemicrania simplex") is a specific neurological disorder characterized by recurrent, throbbing headaches that often affect one side of the head (i.e., it is unilateral), are of at least moderate intensity, and may cause nausea, phonophobia or photophobia. One defining characteristic of the common migraine is a lack of the visual disturbances known as an aura. The exact International Classification of Headache
SUNCT syndrome due to common mis-diagnosis, and setting up diagnostic criteria is important. The International Headache Classification established by the International Headache Society criteria for diagnosing SUNCT for therapeutic purposes is: Symptoms of SUNCT often lead to misdiagnosis as paroxysmal hemicrania, which is also categorized in the same group. Inefficiency of indomethacin usually indicates SUNCT over paroxysmal hemicrania. Misdiagnosis and indecisive diagnosis in the past has made it difficult to obtain accurate statistics about SUNCT. Proper diagnosis will broaden data availability and facilitate discovery of new treatment options and useful statistics. The pathophysiology of SUNCT is incompletely understood. Recent studies suggest the