Differential Diagnosis of Headache

The differential diagnosis of headache is broad and can be categorized based on the likelihood and potential impact of missing a diagnosis. Here's a structured approach:

• Single Most Likely Diagnosis
  • Tension headache: This is the most common type of headache and is often described as a band or a squeezing sensation around the forehead, usually mild to moderate in intensity. It's frequently associated with stress, fatigue, or poor posture.
• Other Likely Diagnoses
  • Migraine: Characterized by severe, throbbing pain, often unilateral, and can be accompanied by nausea, vomiting, and sensitivity to light and sound. Migraines can be triggered by various factors, including hormonal changes, certain foods, and stress.
  • Cluster headache: Known for severe, unilateral pain, typically around the eye, and can occur in clusters or cycles. These headaches are less common but are extremely painful and can be accompanied by nasal congestion or eye watering on the affected side.
  • Sinus headache: Caused by inflammation or infection of the sinuses, leading to pain and pressure in the face, particularly in the cheeks and forehead.
• Do Not Miss Diagnoses
  • Subarachnoid hemorrhage: A life-threatening condition caused by bleeding into the space surrounding the brain, leading to a sudden, severe headache often described as "the worst headache" ever experienced.
  • Meningitis: Inflammation of the protective membranes covering the brain and spinal cord, which can be caused by infection. Symptoms include severe headache, fever, and stiff neck.
  • Temporal arteritis: Inflammation of the blood vessels in the head, which can lead to headache, visual disturbances, and jaw claudication. It's a medical emergency due to the risk of blindness if not promptly treated.
  • Brain tumor: Although rare, headaches can be a symptom of brain tumors, especially if they are large enough to cause increased intracranial pressure.
• Rare Diagnoses
  • Trigeminal neuralgia: A chronic pain condition that affects the trigeminal nerve, which carries sensation from your face to your brain. It's characterized by intense, shock-like or stabbing pain in parts of your face.
  • Hypnic headache: A rare headache disorder that occurs only during sleep and wakes the person up, typically occurring at the same time each night.
  • Thunderclap headache: An extremely severe headache that reaches its maximum intensity within a minute, often described as the worst headache of a person's life. It can be a sign of a subarachnoid hemorrhage or other serious conditions.
  • Idiopathic intracranial hypertension (IIH): A condition characterized by increased pressure within the skull without any apparent cause, leading to headaches, vision changes, and tinnitus.

Each of these diagnoses has distinct characteristics and potential triggers, emphasizing the importance of a thorough medical history and physical examination to guide further diagnostic testing and treatment.