Disorders of the intracranial structures must be considered in the differential diagnosis of patients with orofacial pain. These entities need to be considered first as they may be required immediate attention and should be ruled out from the outset. These disorders can be typified by new or abrupt onset of pain that worsens significantly, pain interrupting sleep, and pain caused by exertion or positional worsening of pain. They may also involve systemic effects such as loss of appetite, weight loss, weakness, difficulty moving, fever with pain, and neurologic signs such as loss of sensation, paralysis, and visual/hearing changes. These entities can stem from neoplasm, infection, stroke, cerebrospinal fluid changes, and blood vessel disease.
The importance of this is underscored by the American Headache Society creating the SNOOP mnemonic to identify signs and symptoms of concern.
S = Systemic symptoms or disease (fever, weight loss, systemic disease such as cancer)
N = Neurologic signs or symptoms (confusion, clumsiness, weakness, difficulty speaking or moving, and visual problems)
O = Onset sudden (abrupt onset, positional worsening, and progressive worsening)
O = Onset after 40
P = Pattern change (existing headache or pain that suddenly worsens, changes in quality, or increases in frequency)