Diagnosis

History

Obtaining a complete headache history is the most vital tool in the diagnosis and management of a patient with headache (Figure 2-1). Items that should be included in the headache history to simplify this process include:

• Type of headache
• Onset
• Frequency
• Site
• Duration
• Severity and character
• Prodromata (symptoms preceding the headache)
• Associated symptoms
• Precipitating factors
• Sleep pattern
• Emotional factors
• Family history
• Medical, surgical, and/or obstetric history
• Allergy
• Previous medications and therapies
• Current medications.

Types of Headache

It is important to determine if the patient is experiencing more than one type of headache. Some patients with a long history of recurrent, one-sided, severe headaches may note a milder daily headache. The patient may also note a change in headache pattern, which could alert the physician to a serious etiology.

Onset

Determining the age at onset of the headaches may provide a significant clue to the type of headache the patient is experiencing. Migraine headaches usually start in adolescence or the early 20s. Patients with cluster headaches will usually describe headache onset in their third, fourth, or fifth decade. Patients with tension-type headaches (TTHs) will note that the headaches started during their 30s or 40s. The clinician should rule out secondary causes (e.g., organic disease) in those patients whose headaches start after age 50.

The patient should also be questioned regarding any specific event that may have precipitated the headache onset, such as:

• Following some type of:
  • Trauma
  • Infection
• In female patients, onset:
  • At menarche
  • During pregnancy
  • At menopause.

Frequency

The frequency of headache attacks not only provides a clue to the diagnosis but also impacts the choice of treatment. Migraine typically occurs with a mean frequency of 1.5 attacks per month. Chronic TTHs are characterized by their daily occurrence. Patients with cluster headaches usually describe a series of headaches, occurring a few times per day for several weeks, and then disappearing for months or years. Headaches associated with organic disease may not demonstrate a particular pattern and may be progressive in frequency as well as other features.

Site

Migraine is typically a one-sided headache, although it may occur bilaterally and may switch sides. Unilateral headaches are also suggestive of organic disease. Cluster headaches are typically one-sided and do not switch sides during a series of headaches. The TTH is notably bilateral and the pain may be described as a tight band around the head (hatband). Patients may also note pain radiating to the neck and shoulder.

Duration

An acute migraine attack usually continues for 4 to 24 hours. However, some patients will experience headaches for ≥3 days and may be classified as suffering from status migrainosus. Cluster headaches are noted for their brief duration, lasting from a few minutes to 3 or 4 hours. The pain associated with trigeminal neuralgia is described as short jabs, lasting a few seconds. Tension-type headaches are continuous with occasional variations in severity.

Severity and Character

The pain of migraine is severe, may be incapacitating, and is described as throbbing or pulsating. Cluster headache pain is depicted as excruciating and may be throbbing or depicted as deep and boring. Chronic TTHs are persistent, dull, aching, or viselike. In headaches due to organic causes, the pain is progressive in nature and intensity.

Migraine Phases and Prodromata

The current understanding of migraine attacks divides these events into four distinct phases (see Figure 3-3). The prodromal phase is characterized by premonitory signs (prodromata), such as intense hunger, yawning, fatigue, or bursts of energy, and occurs hours to days before headache onset. Transient neurological symptoms (normally visual, but sometimes also sensory, language expression-, or motor-related called “aura”) characterize the second phase, which may occur 5 to 60 minutes before the onset of pain. More severe neurologic symptoms, such as ocular paralysis or hemiparesis, may occur with certain types of migraine.

It is important to note that visual symptoms, such as teichopsia (fortification spectrum), may also occur with non-migraine headache, such as secondary headaches due to tumors or angiomata. The headache itself represents the third phase of a migraine attack, while the fourth phase – postdrome – is characterized by “hangover” like symptoms (e.g., fatigue, cognitive dysfunction) which may last up to two days after the headache resolves. While not every patient nor necessarily every attack of migraine will exhibit all four phases, the presence of symptoms associated with specific migraine phases is helpful in both diagnosis and classification; early recognition of prodromata is also important in abortive therapy.

Associated Symptoms

The presence of associated symptoms may also provide clues to the diagnosis. Migraine symptoms include:

• A “sick headache” due to accompanying gastrointestinal symptoms such as:
  • Nausea
  • Vomiting
• Dizziness
• Photophobia and/or phonophobia
• Tinnitus
• Blurred vision.

Cluster headache and other trigeminal autonomic cephalalgias are also characterized by associated symptoms such as:

• Lacrimation
• Facial flushing
• Nasal congestion
• Partial Horner’s syndrome.

Headaches due to organic causes may also occur in association with:

• Double vision
• Seizures
• Tinnitus.

Patients suffering from chronic TTH often provide the treating physician with long lists of somatic, emotional, and psychic symptoms.

Precipitating Factors

An inventory of precipitating factors associated with acute headache attacks may help:

• Determine the diagnosis
• Preventing headache attacks.

Migraine can be triggered by a variety of precipitants such as:

• Diet
• Oversleeping
• Fatigue
• Menstruation
• Changes in weather and barometric pressure
• Foods containing vasoactive substances
• Certain drugs, including:
  • Nitroglycerin
  • Indomethacin.

Stress may trigger any type of headache, and migraine patients will note that an acute migraine attack may occur in a letdown period. During a cluster headache series, alcohol may precipitate an acute attack, although patients usually do not note a relationship outside a cluster period. In patients who relate headache to exertion or straining, the clinician should be suspicious of organic causes, although benign exertional factors may be the mechanism.

Sleep Pattern

Patients presenting with headache should be questioned about any sleep disturbances. Patients with cluster headache typically note that headaches will awaken them at the same time each night during a cluster series. In patients with migraine, the headaches are often present when patients awaken. Patients with chronic TTH will often relate early or frequent awakening. These sleep disturbances may be a manifestation of depression. In headaches due to anxiety, patients usually complain of difficulty falling asleep. Hypertensive headache is characterized by its presence upon awakening and its gradual diminishment during the day. Headache due to acute sinusitis will not be present early in the morning but will occur and increase during the day.

Emotional Factors

When obtaining a headache history, the physician should question the patient about family, marital, and work relationships. Stressors related to the patient’s home or work life can greatly impact on the headache pattern. Because the patient may not feel comfortable with the interviewer during the initial visit, these questions may need to be addressed during later visits.

Family History

Migraine is a familial disorder, and most patients will relate a family history of similar headaches. Patients with cluster headache do not usually relate a family history of headaches. In patients with chronic TTH, a family history of depression may also be reported.

Medical, Surgical, and/or Obstetric History

Patients’ previous history impacts the diagnosis and possible therapy. Physicians should determine any prior incidence of head trauma. Patients should also be questioned regarding any previous neurosurgeries or lumbar punctures. Patients with migraine may note a decrease or remission of headaches during pregnancy.

Allergies

Patients may relate their headaches to specific allergies or sensitivities to foods. A seasonal relationship is noted in cluster headaches, with frequent occurrences in spring and fall.

Previous Medications and Therapies

Patients with chronic headaches may produce an extensive list of previously tried drugs. They have often undergone various tests and consulted several physicians. Determining the success or failure of previous therapies may assist in diagnosing the headache(s) or selecting appropriate treatments.

Current Medications

Clinicians must inventory the medications the patient is currently using. Drugs that may trigger headaches include the following:

• Nitrates
• Reserpine
• Indomethacin
• Minoxidil
• Hydralazine.

Women using oral contraceptives or postmenopausal hormones may note an increase in the severity, frequency, duration, or complications of their migraine attacks.

Physical, Neurologic, and Diagnostic Workup

A thorough physical and neurologic examination is essential to rule out organic pathology for headache as well as to determine which diagnostic tests are required. Simple observation of the patient during the interview process will provide many clues to the clinician. A person with an acute severe headache, whether it be organic or vascular in etiology, may walk and move slowly and deliberately to avoid jarring, which often intensifies the pain. A patient who presents with a calm and relaxed demeanor although complaining of a severe, disabling headache may be suffering from headaches due to depression. The vasomotor instability of migraine may manifest as:

• Blotching of the skin on the chest
• Sweaty palms
• Occasionally, urticaria.

Physical Workup

The physical examination should include:

• Vital signs
  • Fever may be indicative of systemic infection. In the presence of neck stiffness, meningitis must be ruled out.
  • Hypertensive headache occurs with diastolic pressures of 110 mm Hg or higher.
  • Rapid pulse is indicative of vasomotor instability
• Examination of the head
  • Palpation and auscultation
  • Prominent temporal artery may be indicative of:
    • Temporal arteritis, or
    • An acute migraine attack
• Examination of the eyes
  • Characteristics of cluster headaches include:
    • Partial Horner’s syndrome
    • Lacrimation
    • Conjunctival injection
    • Unilateral ptosis
  • Tonometry should be performed on patients over age 40 to rule out glaucoma
• Examination of ears and nose (rule out infection or disease)
• Examination of the face (presence of trigger points is indicative of trigeminal neuralgia)
• Examination of the neck (limitation of motion, spasm, and tenderness should be evaluated).

Neurologic examination should include:

• Systemic examination of the cranial nerves
• Evaluation of motor function
• Sensory testing
• Tests of coordination
  • Evaluate gait
• Finger-to-nose and heel-to-shin tests
• Romberg’s test.

Diagnostic testing may be required to rule out secondary causes of headache and to establish a baseline of some parameters. Although many headache patients have undergone previous testing, repeat testing may be required if the patient’s headache pattern has changed suddenly or if prior results were ambiguous. Invasive testing should be avoided, if possible, as these tests may increase the patient’s headaches or cause more severe complications. Diagnostic testing may include:

• Neuroimaging, including:
  • Computed tomography (CT) scan
  • Magnetic resonance imaging (MRI)
  • Magnetic resonance angiography (MRA)
  • Magnetic resonance venography (MRV)
• Lumbar puncture
• Electroencephalogram (EEG)
• Other diagnostic tests.

Neuroimaging

If the physician is not confident of the diagnosis, or if certain aspects of the history suggest possible organic causes of the headache, neuroimaging should be considered. The Standards of Care of the National Headache Foundation have established guidelines to determine whether neuroimaging is indicated (Table 2-1). In 2019, the American College of Radiology released their Appropriateness Criteria^® for Headache (Table 2-2), a set of recommendations to guide the use of neuroimaging in headache.

Little conclusive evidence is available to recommend one procedure over the other. However, certain exceptions should be noted when ordering these procedures:

• CT scan without contrast for detection of subarachnoid hemorrhage
• MRI for detection of posterior fossa disease as manifested by exertional-, coital-, cough-, or sneeze-induced headache
• MRI in conjunction with MRA for visualization of aneurysm or other vascular lesion.

CT Scan

Computed tomography scanning has precluded the use of hazardous invasive testing. For patients with headache, a CT scan will aid in ruling out disorders that can produce chronic headache, including:

• Brain tumors
• Chronic subdural hematoma
• Hydrocephalus.

Because CT scanning can be performed during an acute migraine attack, it can identify transient morphologic changes after an acute headache, including edema in the cerebral parenchyma. Abnormalities may be demonstrated in CT scans of patients experiencing migraine complications (such as transient cerebral edema). Cerebral ventricle enlargement and cerebral cortical atrophy may be observed in patients with repeated severe attacks.

Magnetic Resonance Imaging

Magnetic resonance imaging has greatly enhanced the physician’s capabilities to uncover occult causes of headaches. MRI can identify lesions that were previously impossible to visualize. This type of imaging can be done in the frontal, sagittal, or axial projections. An important difference between MRI and CT scanning is that CT scanning uses X-rays which produce denser images. However, MRI measures the physical and physiologic functions within brain tissue and can then differentiate various normal structures as well as pathologic tissues. MRI can also detect certain abnormalities at a very early stage, thus allowing for prompt treatment. Because MRI can differentiate white and gray matter within the brain, it can demonstrate several disorders:

• Demyelinated plaques, such as those seen in multiple sclerosis
• Brain tumors
• Strokes
• Brain stem and posterior fossa lesions
• Spinal cord abnormalities
• Herniated intervertebral discs.

If an abnormality of the brain or spinal cord is suspected, MRI should be performed. The procedure can be accomplished without the injection of dye in sensitive patients, and the risk of radiation is absent. Although the majority of headache patients do not need to be evaluated with this procedure, it does offer an excellent tool in ruling out organic disorders.

Magnetic Resonance Angiography

Magnetic resonance angiography can be useful in those patients in whom there is suspicion of a vascular abnormality.

Magnetic Resonance Venography

Magnetic resonance venography can be useful in rare cases of venous thrombosis causing headaches.

Lumbar Puncture

This invasive procedure should only be undertaken if the symptoms warrant. A patient presenting with fever and neck stiffness should undergo a lumbar puncture to rule out intracranial infection. Because herniation of the brain stem into the foramen magnum can occur if spinal fluid is removed suddenly in the presence of a brain tumor, lumbar puncture should be avoided until other diagnostic procedures are performed.

The risk of postspinal puncture headache should be considered before attempting lumbar puncture or spinal anesthesia. This type of headache is described in Post-traumatic Headache.

Electroencephalogram

The EEG is not used extensively because of the availability and efficiency of other tests. This test is indicated in patients presenting with headache accompanied by seizure. Its results are inconclusive in most patients with chronic headache.

Other Diagnostic Tests

Obtaining baseline values for blood chemistries, complete blood count (CBC), and urinalysis will assist the physician in continuing therapy in patients with headache. Hypothyroidism has been noted to cause headache, and thus T₃ and T₄ measurements should be obtained at the initial visit. To rule out temporal arteritis, an erythrocyte sedimentation rate by the Westergren method should be obtained for all patients over the age of 50 with recent onset of headache.

For patients receiving β-blocker or calcium channel blocker therapy, a baseline electrocardiogram (ECG) is essential. With continued therapy, review of laboratory values should be performed periodically to determine if there has been any change due to therapy. With certain medications (e.g., lithium), serum levels must be evaluated to determine dosages.

For patients on anticonvulsant therapy, CBCs and liver enzymes must be evaluated on a regular basis.