Chronic Paroxysmal Hemicrania Workup

Updated: Jun 12, 2019
  • Author: Monica Saini, MD, MBBS; more...
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Workup

Approach Considerations

The diagnosis of chronic paroxysmal hemicrania (CPH) is extremely important because it may lead to lifelong treatment with a potentially noxious drug.

A detailed clinical history in regards to headache characteristics is crucial for diagnosis. Lab studies to evaluate structural, metabolic, and other secondary causes of headache and facial pain are indicated where atypical features are noted. Baseline routine blood tests may be needed to exclude contraindications to certain drugs and to avoid complications from long-term use of various medications.

The INDOTEST (indomethacin 50mg intramuscular [IM] test dose) may be a useful tool in assessment of unilateral headache. Perform this test in a standardized manner. Intramuscular indomethacin 50 mg should result in freedom of attacks within 30 minutes. Oral indomethacin in a daily dose of up to 200 mg is reported to be completely effective, and provides diagnostic certainty.

No characteristic electrocardiographic patterns have been found during attacks of CPH, but marked variations in heart rate and rhythm abnormalities, including bradycardia, sinoatrial block, bundle branch block with episodes of atrial fibrillation, and multiple extrasystoles, have been observed.

Orbital phlebography may be abnormal in some patients, but the significance of this finding has not been established.

In a study of 3 patients with CPH, a slightly lower cerebral vasomotor reactivity was observed in the medial and posterior cerebral arteries on both sides and in the anterior cerebral artery on the symptomatic side than has been found in healthy subjects. These observations may imply an abnormal vascular reactivity in CPH.

In another study, as compared with cluster headache (CH), CPH attacks did not demonstrate any changes in visually evoked event-related potentials (ERPs), latencies, and amplitudes. [22]

Perform ophthalmic evaluation, if needed, to assess ocular pathology such as glaucoma or orbital pseudotumor.

Imaging studies

Computed tomography (CT) scanning or, preferably, magnetic resonance imaging (MRI) of the brain may be needed to rule out structural pathology. Neuroimaging study findings, including those from MRI, are usually normal in patients with CPH.

Consider obtaining an MR angiogram or arteriogram, if necessary, for atypical presentations. Electroencephalography, brain mapping, and other radiologic studies are not required for patients with typical presentations.

Procedures

Consider lumbar puncture, if necessary, for atypical presentations.