The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through representation of such organizations on expert panels. Participation on the expert panel does not necessarily imply endorsement of the final document by individual contributors or their respective organization. Reprint requests to: publications@acr.org OR Headache Discussion of Procedures by Variant Variant 1: Sudden onset severe headache that reaches maximal severity within one hour. Initial imaging. Many of the headaches presenting to the emergency department are benign or primary; however, a subset of headaches defined as TCH warrant further investigation. The most important feature of TCH is the abrupt onset of a severe headache that reaches maximum intensity in <1 minute, although for the purposes of this discussion, the term will be used more loosely to encompass the sudden onset of a severe headache that reaches maximum intensity in <1 hour. Initially used in reference to the pain associated with leaking or ruptured intracranial aneurysms, other etiologies of TCH have since been identified [10,11]. Ruptured aneurysm resulting in subarachnoid hemorrhage (SAH) is the primary concern because of significant morbidity and mortality, although it accounts for only 4% to 12% of acute severe headaches [11]. Reversible cerebral vasoconstriction syndrome (RCVS) is the second most common cause of TCH and is the most common cause of TCH without aneurysmal SAH. Associated complications include intracranial hemorrhage and ischemic infarction [12]. RCVS is an important cause of recurrent TCH; half of RCVS headaches can be attributed to a specific trigger [10,12].
Headache PCAs. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through representation of such organizations on expert panels. Participation on the expert panel does not necessarily imply endorsement of the final document by individual contributors or their respective organization. Reprint requests to: publications@acr.org OR Headache Discussion of Procedures by Variant Variant 1: Sudden onset severe headache that reaches maximal severity within one hour. Initial imaging. Many of the headaches presenting to the emergency department are benign or primary; however, a subset of headaches defined as TCH warrant further investigation. The most important feature of TCH is the abrupt onset of a severe headache that reaches maximum intensity in <1 minute, although for the purposes of this discussion, the term will be used more loosely to encompass the sudden onset of a severe headache that reaches maximum intensity in <1 hour. Initially used in reference to the pain associated with leaking or ruptured intracranial aneurysms, other etiologies of TCH have since been identified [10,11]. Ruptured aneurysm resulting in subarachnoid hemorrhage (SAH) is the primary concern because of significant morbidity and mortality, although it accounts for only 4% to 12% of acute severe headaches [11]. Reversible cerebral vasoconstriction syndrome (RCVS) is the second most common cause of TCH and is the most common cause of TCH without aneurysmal SAH. Associated complications include intracranial hemorrhage and ischemic infarction [12]. RCVS is an important cause of recurrent TCH; half of RCVS headaches can be attributed to a specific trigger [10,12].