CME Recurrent primary thunderclap headache and benign CNS angiopathy Spectra of the same disorder? S.-P. Chen, MD; J.-L. Fuh, MD; J.-F. Lirng, MD; F.-C. Chang, MD; and S.-J. Wang, MD Abstract—Objectives: To investigate the clinical pictures of patients with recurrent thunderclap headaches of un- known etiology and to field-test two relevant International Classification of Headache Disorders, 2nd edition (ICHD- II) criteria, i.e., primary thunderclap headache (Code 4.6) and benign (or reversible) angiopathy of the CNS (Code 6.7.3). Methods: We prospectively recruited patients presenting with idiopathic recurrent thunderclap headaches from a hospital-based headache clinic. Detailed histories, neurologic examinations, and MRIs and magnetic resonance angiographies (MRAs) were performed in all patients to exclude secondary causes. Patients with cerebral vasocon- striction received serial MRA follow-up. Results: Fifty-six consecutive patients (51 female/5 male, mean age 49.6  9.8 [range 22 to 76] years) were enrolled. Segmental vasoconstriction (or benign CNS angiopathy) was found in 22 patients (39%). Thunderclap headache recurred in all patients with a median frequency of 0.7 times per day for a median period of 14 days (range 6 to 86 days). The median duration for each single attack was 3 hours. Most patients (84%) reported at least one trigger. Nimodipine effectively aborted further attacks in 83% of the treated patients. Headache attacks subsided within 3 months. Four patients (7%) developed ischemic complications. Patients with and without vasoconstriction based on MRA images were similar regarding demographics and headache profile. Except for the duration criterion, our patients generally mapped well into the proposed ICHD-II criteria. Conclusions: This study suggests that the two diagnostic entities proposed by the ICHD-II may present different spectra of the same disorder. The distinct headache profile may help physicians quickly recognize this disabling headache disorder with risk of stroke and provide timely treatment. NEUROLOGY 2006;67:2164–2169 Thunderclap headache was first coined by Day and Raskin 1 to describe the symptoms of a patient with an unruptured aneurysm. However, subsequent re- ports 2,3 found that certain patients with thunderclap headache did not have aneurysms but rather seg- mental cerebral vasoconstriction, sine qua non of “Call-Fleming syndrome.” 4 The initial proposed diag- nostic criteria 2,3 classified this headache syndrome into three subtypes: 1) thunderclap headache with- out neurologic signs or symptoms; 2) thunderclap headache with neurologic signs or symptoms; and 3) thunderclap headache associated with intracranial disorders, including subarachnoid hemorrhage (SAH), cerebral venous sinus thrombosis, pituitary apoplexy, etc. In those patients without associated intracranial disorders, i.e., “idiopathic” thunderclap headache, some may exhibit angiographic evidence of reversible segmental vasoconstriction. Recently, the International Classification of Headache Disor- ders, 2nd edition (ICHD-II) 5 adopted primary thun- derclap headache as a primary headache disorder (Code 4.6) and proposed criteria for its diagnosis (ta- ble 1). These criteria define the headache onset, du- ration, and recurrence and highlight the need for normal CSF and angiographic findings in the notes; unlike previous criteria, the neurologic symptoms/ signs are not mentioned. On the other hand, thun- derclap headache with evidence of intracranial vasoconstrictions is treated as a secondary headache disorder and coded as “headache attributed to benign (or reversible) angiopathy of the CNS (Code 6.7.3)” (table 1). However, these two diagnostic criteria have never been field-tested. Even more perplexing, thunderclap headaches elicited by known triggers, e.g., coughing, exertion, or sexual activity, can also be coded separately by the ICHD-II 5 (Codes 4.2– 4.4). Additionally, bathing Additional material related to this article can be found on the Neurology Web site. Go to www.neurology.org and scroll down the Table of Con- tents for the December 26 issue to find the title link for this article. From National Yang-Ming University School of Medicine (S.-P.C., J.-L.F., J.-F.L., F.-C.C., S.-J.W.), Taipei, Taiwan; Neurological Institute (S.-P.C., J.-L.F., S.-J.W.) and Radiology Department (J.-F.L., F.-C.C.), Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine (S.-P.C.), National Yang-Ming University, Taipei, Taiwan; and Neurology Department (S.-P.C.), Taoyuan Veterans Hospital, Taoyuan, Taiwan. Supported by grants from the National Science Council of Taiwan (NSC 93-2314-B-010-044 and NSC 94-2314-B-010-019). Disclosure: The authors report no conflicts of interest. Received June 12, 2006. Accepted in final form September 13, 2006. Address correspondence and reprint requests to Dr. Shuu-Jiun Wang, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan, 112; e-mail: sjwang@vghtpe.gov.tw 2164 Copyright © 2006 by AAN Enterprises, Inc.