Definition: It is pain perceived more than momentarily in the following areas:
- Cranial vault.
- Orbits.
- Nape of the neck.
Pain elsewhere in the face is not considered as headache but as facial pain.
Headache is considered the most common medical complaint as most people experience it at some point in life.
Pathogenesis of headache
Intracranial:
Dilatation, distention, traction, displacement or inflammation of:
- Cerebral vessels.
- Sensitive Portions of meninges.
- 5th, 7th, 9th, 10th, cranial nerves.
- 2nd, 3rd, cervical nerves.
All of which contain pain receptors in contrast to brain tissues that doesn’t contain any nociceptors (pain receptors).
Extracranial:
Sustained contraction of muscles of neck and shoulder.
Causes of Headache and facial pain:
A. Extra-cranial
1. Rhinologic:
Sinusitis:
Contrary to the general belief paranasal sinus disease represents 5-10% of causes of headache, the sinus headache carries the following criteria:
- It starts in the morning around 1 hour after getting out of bed and diminishes or disappears at noon. This periodicity is diagnostic of frontal sinus problem.
- It increases with change of position, bending and straining.
- In cases of impaired aeration of the sinus ostium (as in chronic sinusitis) air pressure inside the sinus drops leading to vacuum headache which is interpreted by patient as lightening sensation around the head.
- In cases of acute infection (as in acute sinusitis) discharge accumulates and the pressure inside the sinus increases resulting in severe headache which is interpreted by patient as bursting headache.
- Site of headache varies according to affected sinus.
Contact Headache:
- Nasal mucosa is found to be rich in pain receptors.
- Any narrowing of nasal pathway as in deviated septum or concha bullosa triggers edema of the nasal mucosa causing pressure on the mucosal nerve endings leading to pain sensation.
Tumors of nose and sinuses:
Benign tumors: as osteoma causes pain due to:
- Pressure on mucosa.
- Traction on nerves.
Malignant tumors: as in squamous cell carcinoma of the maxilla causes pain due to nerve infiltration.
Inflammations:
- Vestibulitis.
- Vestibular furuncle.
2. Nasopharyngeal:
As in nasopharyngeal carcinoma or pharyngitis.
3. Otological:
- Otitis externa.
- Acute suppurative Otitis media.
- Complicated chronic suppurative otitis media (mastoiditis, mening, petrositis and brain abscess).
- Tumors as squamous cell carcinoma of middle ear.
4. Dental:
- Dental caries (The commonest causes of facial pain).
- Pulp space infection (paroxysmal, tooth is sensitive to thermal stimulus).
- Periodontal infections(Constant well localized pain, the affected tooth is sensitive to percussion).
- Post extraction neuralgia: It is either local dull- aching or bursting pain which may spread along the division of mandibular or maxillary nerves.
- Unerupted wisdom tooth.
5. Temporomandibular Joint:
Pain receptors associated with the joint are confined to the joint capsule and articular surfaces.
- Arthritis.
- Dislocation.
- Malocclusion.
6. Ocular:
Headache is frontal and Supraorbital with pain around the eyes. Causes:
- Errors of refraction, especially astigmatism (headache at end of day).
- Acute glaucoma.
- Tumors.
7. Cervical:
- Cervical spondylosis.
- Cervical myalgia.
- It is accompanied by reflex spasm of posterior cervical muscles.
8. Neuralgias:
Definition: Pain felt along the distribution of the nerve due to nerve irritation.
Types:
1ry Neuralgia:
They are characterized by:
- Almost confined to the elderly.
- Brief sharp lancinating pain.
- Sudden onset and offset.
- In a distribution of a nerve.
- With periods of pain free remissions.
2ry Neuralgia:
It is due to pathological involvement of a nerve by an external factor e.g. dental caries.
- Dull aching pain.
- No periods of remission.
- No trigger zone.
Trigeminal neuralgia (Tic douloureux)
- It is usually confined to above 60 years.
- The pain distribution is in the 2nd'and 3rd division of trigeminal nerve.
Glossopharyngeal Neuralgia:
- Paroxysm of stabbing pain starting in the base of the tongue and facial region of one side and often radiates to the ear.
- It is usually provoked by swallowing or coughing.
- It is usually precipitated by sensory stimuli as shaving, teeth brushing.
Treatment of neuralgias:
Medical:
Carbamazepine (Tegretol): It can be given alone or in combination with phenytoin (Epanutin).
Surgical:
In cases resistant to medical treatment.
- Peripheral neurectomy; avulsion of peripheral branches of the affected nerve in trigger zone.
- Decompression of vascular loop compressing sensory root (diagnosed using M.R.A.).
9. Vascular Headache:
- Episodic painful distention of the facial vessels. Its pattern of pain differs from neuralgia.
- The site of headache is related to the arterial distribution and not neurological dermatome as in neuralgias.
9. Systemic Causes of Headache:
- Hypertension.
- Hypotension (more on standing up).
- Premenstrual period.
- Anemia.
- Hypoglycemia.
- Constipation.
B. Intracranial
- Hydrocephalus.
- After lumber puncture, IC hemorrhage.
- Inflammations: meningitis, encephalitis, or abscess.
- Space occupying lesion e.g. tumors, abscess, aneurysm.