A Comprehensive Guide for Doctors on Assessing and Diagnosing Headaches

Headaches are one of the most common complaints encountered in clinical practice. Given the wide variety of potential causes—from benign primary headaches like migraines to life-threatening secondary headaches—thorough assessment is crucial. This comprehensive guide outlines a step-by-step approach to evaluating patients presenting with headaches, emphasizing critical steps and identifying red flags that necessitate urgent intervention.

Step 1: Initial Patient Evaluation
Medical History
A detailed medical history is the cornerstone of headache evaluation. Key components include:

1. Chief Complaint: Document the primary symptom and its characteristics.
   
   
2. History of Present Illness (HPI):
   • Onset: Sudden vs. gradual.
   • Duration: Intermittent vs. continuous.
   • Frequency: Episodic vs. chronic.
   • Intensity: Use a pain scale (e.g., 1-10) to gauge severity.
   • Location: Unilateral vs. bilateral, specific regions.
   • Quality: Throbbing, sharp, dull, pressure-like.
   • Timing: Daily pattern, exacerbation at specific times.
   • Associated Symptoms: Nausea, vomiting, visual disturbances, aura, photophobia, phonophobia, neck stiffness, etc.
   • Triggers: Foods, stress, lack of sleep, hormonal changes.
   • Alleviating Factors: Rest, medications, darkness, cold compress.
3. Past Medical History:
   • Previous headache episodes and diagnoses.
   • Chronic conditions (e.g., hypertension, diabetes).
   • History of trauma or surgery.
4. Family History:
   • Migraines or other headache disorders.
   • Relevant genetic conditions.
5. Social History:
   • Occupational hazards.
   • Lifestyle factors (e.g., stress, sleep patterns, diet, substance use).
6. Medication History:
   • Current medications, including over-the-counter drugs and supplements.
   • Use of headache-specific treatments (e.g., triptans, NSAIDs).

Step 2: Physical Examination
General Assessment

• Vital Signs: Blood pressure, pulse, temperature, respiratory rate.
• General Appearance: Signs of distress, agitation, or lethargy.

Neurological Examination
A comprehensive neurological examination is essential to identify potential causes of secondary headaches:

1. Cranial Nerves:
   • Visual acuity and fields.
   • Fundoscopic examination for papilledema.
   • Pupil reactivity.
   • Eye movements and nystagmus.
   • Facial symmetry and strength.
   • Hearing and balance.
   • Palate elevation and gag reflex.
   • Shoulder shrug and tongue movement.
2. Motor System:
   • Muscle strength and tone.
   • Deep tendon reflexes.
   • Coordination and gait.
3. Sensory System:
   • Light touch, pinprick, temperature, vibration, and proprioception.
4. Cerebellar Function:
   • Finger-to-nose test.
   • Heel-to-shin test.
   • Romberg test.
5. Meningeal Signs (if indicated):
   • Neck stiffness.
   • Brudzinski’s and Kernig’s signs.

Step 3: Differential Diagnosis
After history and physical examination, the next step is to develop a differential diagnosis. Headaches are broadly classified into primary and secondary types. This section delves deeply into these categories, elucidating the characteristics and pathophysiology of various headache types.

Primary Headaches
Primary headaches are those not caused by another medical condition. They include migraines, tension-type headaches, and cluster headaches.

1. Migraine:
   • Epidemiology: Affects approximately 12% of the population, more common in women.
   • Pathophysiology: Believed to involve neurovascular mechanisms, with a combination of genetic and environmental factors. The trigeminovascular system plays a central role.
   • Clinical Features:
     • Typically unilateral, throbbing or pulsating pain.
     • Moderate to severe intensity.
     • Associated with nausea, vomiting, photophobia, and phonophobia.
     • Often preceded by an aura (visual disturbances, sensory changes).
   • Diagnosis: Clinical, based on criteria (e.g., International Classification of Headache Disorders).
   • Treatment:
     • Acute: Triptans, NSAIDs, antiemetics.
     • Preventive: Beta-blockers, antiepileptics, antidepressants.
2. Tension-Type Headache:
   • Epidemiology: Most common type of primary headache.
   • Pathophysiology: Thought to be related to muscle tension and stress, but exact mechanisms are unclear.
   • Clinical Features:
     • Bilateral, pressing or tightening pain (non-pulsating).
     • Mild to moderate intensity.
     • Not aggravated by routine physical activity.
     • No significant nausea, vomiting, or photophobia.
   • Diagnosis: Clinical, with criteria focused on pain characteristics and associated symptoms.
   • Treatment:
     • Acute: NSAIDs, acetaminophen.
     • Preventive: Stress management, physical therapy, antidepressants.
3. Cluster Headache:
   • Epidemiology: Less common, affects men more frequently.
   • Pathophysiology: Involves the hypothalamus, trigeminal nerve, and autonomic nervous system. The exact cause is not well understood.
   • Clinical Features:
     • Severe unilateral pain, often periorbital or temporal.
     • Short duration (15-180 minutes), but occurs in clusters (e.g., daily for weeks).
     • Accompanied by autonomic symptoms: lacrimation, nasal congestion, ptosis, miosis.
     • Restlessness and agitation during attacks.
   • Diagnosis: Clinical, based on attack pattern and associated symptoms.
   • Treatment:
     • Acute: High-flow oxygen, subcutaneous or intranasal triptans.
     • Preventive: Verapamil, lithium, corticosteroids.

Secondary Headaches
Secondary headaches are those caused by an underlying medical condition. They can be indicative of serious pathology and require thorough investigation.

1. Intracranial Hemorrhage:
   • Types: Subarachnoid hemorrhage, intracerebral hemorrhage.
   • Clinical Features:
     • Sudden, severe headache ("thunderclap").
     • Neurological deficits: weakness, numbness, aphasia.
     • Altered consciousness.
   • Diagnosis:
     • Immediate CT scan to identify hemorrhage.
     • Lumbar puncture if CT is negative but suspicion remains.
   • Management: Emergency neurosurgical intervention, supportive care in ICU.
2. Meningitis/Encephalitis:
   • Etiology: Bacterial, viral, fungal infections.
   • Clinical Features:
     • Severe headache with fever.
     • Neck stiffness, photophobia.
     • Altered mental status, seizures.
   • Diagnosis:
     • Lumbar puncture for CSF analysis.
     • Blood cultures, imaging if indicated.
   • Management:
     • Empirical antibiotics/antivirals pending culture results.
     • Supportive care, monitoring for complications.
3. Giant Cell Arteritis:
   • Epidemiology: Typically affects individuals >50 years.
   • Pathophysiology: Inflammation of large and medium-sized arteries, particularly temporal arteries.
   • Clinical Features:
     • Temporal headache, scalp tenderness.
     • Jaw claudication, visual disturbances.
     • Systemic symptoms: fatigue, weight loss.
   • Diagnosis:
     • Elevated ESR and CRP.
     • Temporal artery biopsy.
   • Management:
     • High-dose corticosteroids.
     • Monitoring for complications like vision loss.
4. Brain Tumor:
   • Epidemiology: Can occur at any age, but certain types are more common in specific age groups.
   • Pathophysiology: Mass effect, increased intracranial pressure, infiltration of brain tissue.
   • Clinical Features:
     • Progressive headache, often worse in the morning.
     • Neurological deficits: weakness, visual disturbances, seizures.
   • Diagnosis:
     • MRI with contrast.
     • Biopsy for histological diagnosis.
   • Management:
     • Surgical resection if feasible.
     • Radiotherapy, chemotherapy based on tumor type.
5. Substance Withdrawal:
   • Etiology: Withdrawal from caffeine, alcohol, medications (e.g., analgesics, opioids).
   • Clinical Features:
     • Headache onset correlates with cessation or reduction of substance use.
     • Associated symptoms: agitation, tremors, anxiety.
   • Diagnosis:
     • Clinical, based on history of substance use.
   • Management:
     • Gradual tapering of the substance if safe.
     • Symptomatic relief: hydration, analgesics.
6. Sinusitis:
   • Etiology: Inflammation of paranasal sinuses, often following upper respiratory infections.
   • Clinical Features:
     • Facial pain/pressure, especially in the frontal or maxillary regions.
     • Nasal congestion, purulent nasal discharge.
     • Worse with bending forward.
   • Diagnosis:
     • Clinical examination, sometimes confirmed with imaging (e.g., sinus CT).
   • Management:
     • Antibiotics if bacterial infection

​