Patient's question:
Main symptoms: Headache. Since mid-August, he occasionally mentions headaches, each lasting only a moment and occurring at unpredictable locations—sometimes at the front, sometimes at the back. Sometimes he has one or two a day, while other days he has more. In the past week, the frequency has increased, with the pain mostly on the right side of his head. In late August, he was examined at the children's hospital, and CT, EEG, and CBF tests all showed normal results. However, he still complains of pain daily, and the frequency has also increased. What should we do? We are very worried!! Our child is a very understanding kid and wouldn't lie about this!! Please help, kind doctors!! Onset date: August 15 First mention of headache. Test results:Doctor's answer:
Headache is one of the most common symptoms in clinical practice, with a wide range of causes, some of which are severe and life-threatening. However, the diagnosis of the underlying cause is often challenging. This article focuses on the diagnostic aspects of headaches, including essential knowledge and thought processes required for diagnosis, followed by an introduction to treatment principles and the management of common types of headaches.Headache Terminology
Headache refers to pain in the entire head, including the front, back, and lateral regions. It can be caused by external pathogens (such as the six evils), internal injuries to the viscera, blockage of yang qi, ascension of turbid pathogens, hyperactivity of liver yang, deficiency of essence, blood, and qi, or dysfunction of meridians. Headaches are classified into two categories based on etiology: external and internal.
- External Headaches: Caused by cold, wind, dampness, heat, fire, or cold-induced pathogens. Examples include headaches due to cold, wind-heat, dampness, summerheat, fire, or cold-induced pathogens, as well as headaches from cold damage.
- Internal Headaches: Caused by qi deficiency, blood deficiency, yang deficiency, yin deficiency, liver yang hyperactivity, dietary indiscretion, blood stasis, etc.
From a meridian perspective, headaches are classified as Three Yang Headaches (Taiyang, Yangming, Shaoyang) or Three Yin Headaches (Taiyin, Shaoyin, Jueyin). Based on severity, duration, pattern of onset, and location of pain, headaches are further categorized as True Headache, Head Wind, Migraine, Thunder Headache, Brain Wind, Crown Headache, Chronic Headache, etc. See individual sections for details.
Key Aspects of Headache Diagnosis
The key to diagnosing headaches lies in:
1. Understanding the pathogenesis of headaches.
2. Having a systematic grasp of common causes and their characteristic symptoms.
3. Emphasizing and mastering a set of diagnostic techniques.
4. Conducting targeted and focused examinations.
Pathogenesis of Headache
Headache occurs when pain receptors in the head and neck are stimulated, generating abnormal nerve impulses that reach the brain. Extracranial tissues, including the skull itself, periosteum, and orifices and oral cavity, are sensitive to pain. Intracranial tissues are sensitive only to pain from venous sinuses, venous, dura mater, and basilar arteries; other brain tissues are insensitive to pain. Intracranial pain is transmitted via the fifth, fourth, and tenth cranial nerves, as well as the second and third cervical nerves. Extracranial pain can also be transmitted via sympathetic nerves.
The primary mechanisms of headache include:
1. Vasodilation of intracranial and extracranial arteries (vascular headaches).
2. Traction or displacement of intracranial pain-sensitive tissues (traction headaches).
3. Inflammation of intracranial pain-sensitive tissues (e.g., meningeal irritative headaches).
4. Contraction of extracranial muscles (tension or muscular contraction headaches).
5. Direct damage or inflammation of cranial and cervical nerves that transmit pain (neural inflammatory headaches).
6. Pain radiation from ocular, nasal, or auditory lesions (referred headaches).
Neurotransmitters such as substance P, neurokinin A, 5-hydroxytryptamine (5-HT), calcitonin gene-related peptide (CGRP), vasoactive intestinal peptide (VIP), and prostaglandin (PGE) are involved in the development of these headaches. Additionally, psychological factors can also cause headaches, possibly due to a lowered pain tolerance threshold. Like any pain, the severity of headache varies among individuals, and the same patient’s headache may differ based on their physical and mental condition at the time. Moreover, the pathogenesis of headaches in some diseases is often multifactorial. For example, hypertensive headaches may involve both vascular headaches related to blood pressure and muscular contraction headaches linked to emotional stress. The latter can be relieved once blood pressure returns to normal. Understanding these mechanisms is crucial for headache prevention and treatment.
Symptoms of Common Causes of Headache
For clinical systematic thinking, common headache causes can be categorized into four groups:
1. Headaches Caused by Intracranial Lesions
These are often severe, deep,, or explosive in nature, frequently accompanied by nausea, neurological deficits, convulsions, altered consciousness, psychiatric symptoms, or changes in vital signs.
- (a) Meningoencephalitis: Causes meningeal irritative headaches, with neck pain and meningeal signs. Onset is usually abrupt, with fever and positive cerebrospinal fluid (CSF) findings.
- (b) Cerebrovascular Diseases:
1. Hemorrhagic Cerebrovascular Disease: Intracerebral hemorrhage often causes severe headaches but is not the primary reason for consultation. Subarachnoid hemorrhage, however, is often diagnosed based on headache, as it may be missed due to the absence of focal neurological signs like hemiplegia. Onset is sudden, with severe headache, vomiting, and meningeal irritative features. Causes include congenital aneurysms, arteriovenous malformations, and cerebral arteriosclerosis. Old hemorrhagic CSF can confirm the diagnosis.
2. Ischemic Cerebrovascular Disease: Cerebral thrombosis rarely causes headaches, but transient ischemic attacks (TIAs) of vertebrobasilar artery origin are common. Diagnostic criteria include:
- Headache triggered by head movement or upright posture.
- Associated brainstem TIA symptoms (e.g., vertigo, flickering scotomas, visual disturbances, facial or oral numbness, ear pain, altered vision) before, during, or after the headache.
- Mild brainstem deficits (e.g., nystagmus, delayed or absent corneal or pharyngeal reflexes, balance disorders, positive pathologic reflexes).
- Clear etiology (e.g., arteriosclerosis, diabetes, coronary heart disease, cervical spondylosis, trauma, or deformity).
- Positive laboratory findings (e.g., brain blood flow mapping, extracranial vertebral artery Doppler ultrasound, nystagmus).
The mechanism of headache in ischemic cerebrovascular disease may involve insufficient intracranial blood supply and compensatory extracranial vasodilation, giving it features of vascular headaches.
3. Cerebral Arteriosclerosis: Caused by cerebral hypoxia. Headaches are often accompanied by neurotic symptoms, and in hypertensive patients, they may resemble hypertensive headaches, with mild neurological deficits and signs of arteriosclerosis in the funduscopy, heart, and elevated blood lipids.
4. Hypertensive Encephalopathy: In hypertensive patients, sudden increases in blood pressure leading to spasm of cerebral small arteries and acute cerebral edema can cause severe headaches. Fundoscopy may show retinal artery spasm, hemorrhage, or exudation. This is more common in uremia and eclampsia.
- (c) Intracranial Tumors and Increased Intracranial Pressure: Includes brain tumors, abscesses, intracranial hematomas, cysts (meningitis), and cerebral parasites.
- Tumors may compress or displace pain-sensitive intracranial tissues, causing localized or adjacent headaches (traction headaches). For example, a pituitary tumor may cause bilateral temporal or retroorbital, with progressive worsening and focal neurological signs.
- 80% of tumor patients have increased intracranial pressure, leading to diffuse headache, with early morning onset (due to venous congestion after lying flat overnight), gradual persistence, worsening with coughing or exertion, and associated symptoms like vomiting, papilledema, retinal hemorrhage, psychiatric symptoms, or epilepsy. See Section 5 for details.
- (d) Low Intracranial Pressure Syndrome: Often occurs after lumbar puncture, head trauma, surgery, meningitis, or severe dehydration. Lateral decubitus lumbar puncture shows CSF pressure below 0.59–0.78 kPa (70–80 mm H?O) or no flow at all. Sudden severe headaches upon sitting up, accompanied by nausea and vomiting, result from further drops in intracranial pressure, causing traction of pain-sensitive tissues without CSF support. This is also a traction headache, relieved by lying flat. Occasionally, bradycardia and elevated blood pressure may occur.
- (e) Epileptic Headaches: More common in children and adolescents, characterized by severe throbbing or explosive pain, with abrupt onset and termination lasting seconds to hours, occasionally up to a day. May be accompanied by nausea, vomiting, vertigo, rhinorrhea, lacrimation, abdominal pain, altered consciousness, or anxiety. EEG may show epileptic waves during attacks, along with a history of other types of seizures, family history, or relevant etiology. Antiepileptic drugs can control attacks. Possible causes include abnormal discharges in the interbrain due to various diseases.
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