Differential Diagnosis for Headache Disorders

When differentiating between tension-type headache (TTH), cluster headache, and migraine, it's crucial to consider the distinct characteristics of each condition. Here's a structured approach to the differential diagnosis:

• Single Most Likely Diagnosis
  • Migraine: Often presents with unilateral, pulsating headaches of moderate to severe intensity, accompanied by nausea, vomiting, photophobia, and phonophobia. It's one of the most common headache disorders and should be considered first due to its prevalence.
• Other Likely Diagnoses
  • Tension-Type Headache (TTH): Characterized by bilateral, non-pulsating headaches of mild to moderate intensity, often described as a band or a squeezing sensation around the forehead, back of the neck, or both. It's very common and can be considered if the headache lacks migrainous features.
  • Cluster Headache: Known for its severe, unilateral orbital, supraorbital, or temporal pain lasting 15-180 minutes, occurring in clusters or periods. It's less common than migraine or TTH but should be considered for its distinct periodicity and severity.
• Do Not Miss Diagnoses
  • Subarachnoid Hemorrhage: Although rare, it's a medical emergency that can present with a sudden, severe headache (often described as "the worst headache of my life"), which may mimic a migraine or cluster headache in its severity but is distinguished by its abrupt onset.
  • Temporal Arteritis: Particularly in older adults, this condition can cause headaches that may resemble TTH or migraine but is distinguished by jaw claudication, visual disturbances, and an elevated erythrocyte sedimentation rate (ESR).
  • Idiopathic Intracranial Hypertension: Can present with headaches that worsen with recumbency and are accompanied by papilledema, tinnitus, and visual obscurations.
• Rare Diagnoses
  • Hemicrania Continua: A rare headache disorder characterized by a continuous, unilateral headache with periods of exacerbation, often accompanied by autonomic features like conjunctival injection and lacrimation.
  • Short-Lasting Unilateral Neuralgiform Headache Attacks with Conjunctival Injection and Tearing (SUNCT) / Short-Lasting Unilateral Neuralgiform Headache with Autonomic Features (SUNA): Extremely rare conditions presenting with very short-lasting but extremely painful headaches accompanied by prominent autonomic symptoms.
  • Trigeminal Neuralgia: While not typically considered a primary headache disorder, it can cause severe, brief, stabbing pains in the face, often triggered by light touch or eating, which might be confused with the pain location of cluster headaches.

Each of these diagnoses has distinct features that can guide a clinician towards the correct diagnosis. A thorough history, physical examination, and, when necessary, diagnostic tests are crucial for accurately differentiating between these conditions.