What are the diagnostic criteria and treatment options for paroxysmal hemicrania?

Diagnostic Criteria and Treatment Options for Paroxysmal Hemicrania

Diagnostic Criteria

Paroxysmal hemicrania is characterized by strictly unilateral, severe, short-lasting headache attacks with associated cranial autonomic features and an absolute response to indomethacin. 1, 2

Core Clinical Features:

• Strictly unilateral pain, typically in the orbital, temporal, and retro-orbital regions 1
• Short-lasting attacks with mean duration of approximately 17 minutes 1
• High attack frequency (mean of 11 attacks per day) 1
• Associated cranial autonomic symptoms during attacks 1, 2
• Complete response to indomethacin (the sine qua non for diagnosis) 1, 2

Cranial Autonomic Features:

• Lacrimation (87% of patients) 1
• Conjunctival injection (68%) 1
• Rhinorrhea (58%) 1
• Nasal congestion (54%) 1
• Ptosis (54%) 1
• Facial flushing (54%) 1
• Other features may include eyelid edema, facial sweating, aural fullness, and periauricular swelling 1

Behavioral Features:

• Agitation or restlessness during attacks (80% of patients) 1
• Aggressive behavior may be present (26%) 1

Diagnostic Testing

An indomethacin test is essential for confirming the diagnosis of paroxysmal hemicrania. 1, 2

Indomethacin Testing Options:

• Oral indomethacin trial (typically 25-50 mg three times daily, increasing to 75 mg three times daily if needed) 1, 2
• Intramuscular indomethacin test (100-200 mg) for faster confirmation 1
• Complete resolution of attacks with indomethacin is required for diagnosis 1, 2

Differential Diagnosis

Paroxysmal hemicrania must be distinguished from other primary headache disorders:

• Cluster headache: Longer attack duration (15-180 minutes vs. <20 minutes in PH) and lower frequency (1-8 attacks per day) 2, 3
• SUNCT/SUNA: Very brief attacks (seconds to minutes) and lack of indomethacin response 2
• Other short-lasting unilateral headaches 2

Treatment Options

First-Line Treatment:

• Indomethacin is the definitive treatment for paroxysmal hemicrania and provides complete pain relief in most patients. 1, 2, 3
• Typical dosage ranges from 25-75 mg three times daily 2
• Gastrointestinal protection with proton pump inhibitors may be needed for long-term use 3

Alternative Treatments (for indomethacin-intolerant patients):

• Other NSAIDs may be partially effective:
  • Acetylsalicylic acid (aspirin) 4
  • Naproxen 4
  • Diclofenac 4
• Calcium channel blockers:
  • Verapamil has shown efficacy as a second-line option 4, 5
• Other options with variable response:
  • Topiramate 2
  • COX-2 inhibitors 2
  • Epicranial nerve blocks 2
  • Sumatriptan (partial efficacy in some cases) 4

Refractory Cases:

• Hypothalamic deep brain stimulation has been used in treatment-resistant cases 2

Important Considerations

• Some patients may not perfectly fit the classic phenotype but still respond to indomethacin 3, 5
• Approximately 2% of headache clinic patients may have paroxysmal hemicrania 5
• The condition is often misdiagnosed as sinusitis due to the autonomic features 3
• Some patients (9-17%) may not respond completely to indomethacin despite having clinical features of paroxysmal hemicrania 5