1. Cluster Headache Two types:
a) The episodic type: is most common and is characterized by 1-3 short-lived attacks of periorbital
pain per day over a 4- to 8-week period, followed by a pain-free interval that averages 1 year.
b) The chronic form: which may begin de novo or several years after an episodic pattern has become established.
It is characterized by the absence of sustained periods of remission.
Each type may transform into the other.

2. Men are affected 7 - 8 times more often than women.
Hereditary factors are usually absent (usually negative family history).
The onset is generally between ages 20 and 50 while the migraine has earlier onset: typically start in teenage & rarely after 40.
However C.H may occur as early as the first decade of life.
Propranolol and amitriptyline which are used in migraine as prophylactic measures are largely ineffective in C.H.
Lithium is beneficial for cluster headache and ineffective in migraine.

3. Clinical Features:
• Periorbital or, less commonly, temporal pain begins without aura and reaches a crescendo within 5 min.
• It is often excruciating in intensity and is deep, non-throbbing, but explosive in quality.
• only rarely C.H it pulsatile.
• Pain is strictly unilateral and usually affects the same side in subsequent months.
• Attacks last from 30 min to 2 h.
• There are often associated symptoms of homolateral lacrimation, reddening of the eye, nasal stuffiness, Horner’s syndrome.
• Gastrointestinal symptoms like vomiting are not typical of C.H as opposite to the migraine. However nausea occur in 40% of cases of C.H.
• Alcohol provokes the already ongoing attacks in about 70% of patients but ceases to be provocative when the bout remits; this on-off vulnerability to alcohol is pathognomonic of cluster headache.
• In contrast to migraine, C.H rarely precipitated by emotional factors or foods (tyramine like cheese, monosodium glutamate like Chines & Mexican food, nitrates like smoked meats).

4. There is a striking periodicity of attacks in at least 85% of patients.
At least one of the daily attacks of pain reoccurs at about the same hour each day for the duration of a cluster bout.
Onset is nocturnal in about 50% of the cases, and then the pain usually awakens the patient within 2 h of falling asleep.

5. Pathogenesis:
• No consistent cerebral blood flow changes accompany attacks of pain.
The hypothalamus is probably the site of activation in this disorder.
Activation of the posterior hypothalamus lead autonomic features, and activation of the anterior hypothalamus lead to episodic course of disease.
Activation of both is necessary to explain the symptoms of cluster headache.

6. Differential diagnosis: from 1) trigeminal neuralgia that effect the ophthalmic division of the trigeminal nerve. In trigeminal neuralgia the pain is superficial & last up to 2 minute per attack while in cluster headache the pain is deep & last at least for 30 minutes.
2) Chronic paroxysmal hemicrania which is a condition mimic cluster headache with same autonomic features, but each attack of headache last from 5 – 20 minutes only. Victim usually women. It respond well to indomethacin.

7. Treatment:
a) Acute attack:
Use one of the following:
– 100 % Oxygen 8-10 L/minute for minutes.
– Sumatriptane 12 mg S.C injection (oral preparation is useless).
– Dihydroergotamine 1-2 mg I.M or S.C injection mg I.V injection.
– Xylocaine nasal spray.
– Prednisolone 60 mg in the 1st day
40 mg in the 2nd day
20 mg in 3rd day
Regard Prednisolone the pain may resolve within hours, and most patients who respond do so within 2 days.

8. b) Prophylactic treatment (is a must in every case & should be started during the aleardy ongoing cluster bout just after the respond to acute phase therapy & stoped when the bout ends)
Use one of the following:
– Verapamil (Isoptine)® SRP mg/d.
– Sumatriptan S.C injection.
– Ergotamine/caffeine (Migrail® or Cafergot®) rectal suppositories or dihydroergotamine subcutaneously at bedtime may be especially helpful for nocturnal headaches.
– Prednisolone mg/d for 1 week then taper over 3 weeks.
– Lithium carbonate or citrate syrup 300 mg qd or tid. This option especially preferable for bilateral variant that occur usually in elderly. Serum lithium levels should be measured at weekly intervals for the first several weeks and should be maintained < 1.2 meq/L to reduce the likelihood of adverse effects (nausea, diarrhea, polyuria, renal failure, hypothyroidism, tremor, dysarthria, ataxia, myoclonus, and seizures).
– Chronic rather than episodic cluster headaches may respond dramatically to indomethacin, 25 mg three times daily.

9. Trigeminal Neuralgia (Tic Douloureux)
• Is a facial-pain syndrome.
• develops in middle to late life.
• 60 % of cases in wemen.
• In many instances, the trigeminal nerve roots are close to a vascular structure, and microvascular compression of the nerve is believed to cause the disorder.
• Pain is confined mainly to the area supplied by the second and third divisions of the trigeminal nerve (3rd affected more than 2nd). Involvement of the first division or bilateral disease occurs in less than 5% of cases.
• Bilateral cases occur in multiple sclerosis.
• Characteristically, lightninglike momentary jabs of excruciating pain occur lasting from seconds up to 2 minutes and spontaneously abate.
• Occurrence during sleep is rare. Such occurrence suggest C.H rather than T.N
• Pain-free intervals may last for minutes to weeks, but long-term spontaneous remission is rare.
• Sensory stimulation of trigger zones about the cheek, teeth, nose, or mouth by touch, cold, wind, talking, swallowing or chewing can precipitate the pain.
• Physical examination discloses no abnormalities.

10. Differential diagnosis:
Rarely, similar pain may occur in
– multiple sclerosis
– brainstem tumors
These possibilities should thus be considered in young patients and in patients who show neurologic abnormalities on examination at any age.
– Temporal arteritis enter into the differential diagnosis.
– Trigeminal neuralgia that affect 1st division of trigeminal nerve should be differentiated from cluster headache.

11. Investigations:
In idiopathic cases, CT scan and MRI fail to show any abnormality, and arteriography is similarly normal. Any vascular structure compressing the nerve roots is generally too small to be seen by these means. An ESR & temporal artery biopsy is indicated if temporal arteritis is suspected.

12. Treatment:
• Remission of symptoms with carbamazepine (Tegretol)® tab. (200 mg/tab.), 400–1200 mg/d orally in three divided doses, occurs within 24 hours in a high percentage of cases. Rarely, blood dyscrasia occurs as an adverse reaction to carbamazepine.
• The recent availability of oxcarbazepine (Trileptal)® (600–1800 mg/d in two divided doses) appears equally effective; blood dyscrasias have not been reported.
• Intravenous administration of 250 mg of phenytoin (Epanutin)® ampoule (1 ampoule contain 250 mg), will abort an acute attack, and phenytoin (Epanutin)® capsule (100 mg/capsule), 200–400 mg/d orally in single dose, may be effective alone or in combination with carbamazepine if a second drug is necessary.
• Lamotrigine (Lamictal)® (25, 50, 100, 200 mg/tab) 400 mg/d÷2 or baclofen (Lioresal)® tab. (5, 10, 25 mg/tab.) 10 mg three times daily–20 mg four times daily has been used in refractory cases.
Posterior fossa microvascular decompressive surgery has been used in drug-resistant cases.

13. Idiopathic Intracranial Hypertension
Idiopathic intracranial hypertension (pseudotumor cerebri) is characterized by a diffuse increase in intracranial pressure causing headache, papilledema, pulsatile tinnitus, visual loss and diplopia as a result of abducens nerve palsy.
Although intracranial hypertension can accompany many disorders, most cases are idiopathic.
In the idiopathic variety, women are affected much more commonly than men, with a peak incidence in the third decade (young). Most patients are obese.
Diffuse headache is almost always a presenting symptom. Transient visual obscurations (lasting for seconds) and visual blurring occur in most cases. Visual acuity is normal in most patients at presentation; moderate to severe papilledema is seen in almost all cases. Visual loss from increased intracranial pressure, like that of glaucoma, is characterized by gradually constricting visual fields with late loss of central acuity. Secondary optic atrophy with blindness can happen in sever untreated cases.

14. Normal disc

15. Primary Optic Atrophy

16. Papilloedema

17. Secondary Optic Atrophy

18. Disorders Associated with Intracranial Hypertension:
– Intracranial venous drainage obstruction (eg, venous sinus thrombosis, head trauma, polycythemia, thrombocytosis)
– Endocrine dysfunction (eg, obesity, withdrawal from steroid therapy; Addison disease; hypothyroidism; hypoparathyroidism)
– Vitamins (eg, hypervitaminosis A and 13 cis retinoic acid in children and adolescents);
– severe iron deficiency anemia;
– tetracycline, minocycline, nalidixic acid)
– Other (eg, chronic hypercapnia, severe right heart failure, chronic meningitis, hypertensive encephalopathy)

19. The idiopathic intracranial hypertension is generally self limited over several months (may reach 6 months).
Recurrent symptomatic episodes occur in 10%.
Even though the papilledema may disappear after end of disease attack, CSF opening pressure remains elevated for years, so measuring CSF opening pressure is useless to diagnose recurrence of disease which should be made at clinical & radiological bases.
N.B: Normal value of C.S.F opening pressure is from mmH2O / mmC.S.F

20. Differentiating diagnosis:
It should differentiated from intracerebral mass lesions and from the disorders listed above including connective tissue diseases that cause vinous sinus thrombosis.
Investigations: should include:
1) MRI & 2) CT brain scanning to exclude mass lesions.
In idiopathic cases imaging studies may show small (slitlike) ventricles with effacement of groves and demonstrate an empty sella in 70% of instances. Dilation of the optic nerve sheath and flattening of the back of the globe are characteristic.

21. Small Ventricles + Effacement of Groves

22. 3) MRV to exclude cerebral vinous sinus thrombosis.
then
4) Lumbar puncture after exclusion of mass lesions by brain imaging.
Elevation of intracranial pressure can be documented by lumbar puncture; removal of 20–40 ml CSF may transiently relieve headache. Cells, glucose, and protein content of the CSF are normal. Normal C.S.F opening pressure does not exclude the diagnosis because it is subjected to diurnal variation i.e.:it may be normal at morning but elevated at night.
5) Connective tissue screening tests to exclude connective tissue diseases like, antiphospholipid syndrome, Behecet disease, S.L.E which cause vinous sinus thrombosis. So send for lupus anticoagulant, anticardiolipin antibodies, KCT, antiDS DNA, ANA, Rh.factors.

23. Treatment:
If a specific cause is identified, it must be treated appropriately.
Treatment with acetazolamide (Dimox or Cidamex)® tab. which is carbonic anhydrase inhibitor (250 mg/tab.) 250 mg tid, with or without a diuretic eg, furosemide (Lasix)® tab. (40 mg/tab.) 40–60 mg twice daily, my be adequate to control mild cases.
In more sever case we add corticosteroids which are effective but have untoward side effects. We add Prednisolone (5 mg/tab) mg/d=( tab/d).
Topiramate seems to be effective in the treatment of IIH. Weight reduction as well as the reduction of the CSF formation is the possible mechanism of action.
The medical therapy should continue till the end of attack which my last for 6 months.
In refractory cases, repeated lumber punctures, optic nerve sheath fenestration, or lumboperitoneal or ventriculoperitoneal shunting may be needed to protect vision and decrease headache.