Published by Wiley Periodicals, Inc. Cluster Headache—Acute and Prophylactic Therapyhead_1830272.286 Cluster headache (CH) pain is the most severe of the primary headache syndromes. It is characterized by periodic attacks of strictly unilateral pain associated with ipsilateral cranial autonomic symptoms. The majority of patients have episodic CH, with cluster periods that typically occur in a circannual rhythm, while 10% suffer from the chronic form, with no significant remissions between cluster periods. Sumatriptan injection or oxygen inhalation is the first-line therapy for acute CH attacks, with the majority of patients responding to either treatment. The calcium channel blocker verapamil is the drug of choice for CH prevention. Other drugs that may be used for this purpose include lithium carbonate, topiramate, valproic acid, gabapentin, and baclofen. Transitional prophylaxis, most commonly using corticosteroids, helps to control the attacks at the beginning of a cluster period. Peripheral neural blockade is effective for short-term pain control. Recently, the therapeutic options for refractory CH patients have expanded with the emergence of both peripheral (mostly occipital nerve) and central (hypotha- lamic) neurostimulation. With the emergence of these novel treatments, the role of ablative surgery in CH has declined. Key words: cluster headache, acute therapy, prophylactic therapy Abbreviations: AEs adverse effects, CCH chronic cluster headache, CH cluster headache, DHE Dihydroergotamine, ECH episodic cluster headache, GON greater occipital nerve, HBO hyperbaric oxygen, HS hypothalamic stimula- tion, NBO normobaric oxygen, ONS occipital nerve stimulation, SPG sphenopalatine ganglion
Cluster headache (CH) pain is considered the
ipsilateral to the pain. Patients typically pace rest-
most severe of the primary headache syndromes and
lessly during an acute attack. The hallmark of CH is
is arguably one of the most severe pain syndromes
the circadian periodicity of the attacks. Also, in epi-
that afflict humans.1 The disorder is characterized by
sodic CH (ECH), the cluster periods often occur at
attacks of severe, strictly unilateral pain, typically in
predictable times of the year (circannual periodicity).
the retro-orbital and fronto-temporal areas, associ-
Recent imaging studies confirm activation of the
ated with symptoms and signs of cranial autonomic
hypothalamus during CH attacks.2 These findings may
explain the characteristic periodicity of CH. Activa-
rhinorrhea/nasal congestion, and Horner’s syndrome)
tion of the trigeminovascular system has also beenshown during acute attacks. From the The Neurologic Group of Bucks/Montgomery
The management of CH includes: (1) patient edu-
County—Neurology, Doylestown, PA, USA (A. Ashkenazi);
cation about the nature of the disorder; (2) advice on
Washington University School of Medicine—Neurology, St. Louis, MO, USA (T. Schwedt).
lifestyle changes (eg, avoiding alcohol during anactive cluster period); (3) prompt treatment of the
Address all correspondence to A. Ashkenazi, The Neurologic Group of Bucks/Montgomery County, 800 West State Street,
acute attack; and (4) prophylactic treatment. Most
Suite 101, Doylestown, PA 18901, USA.
patients can be managed with medical therapy. Accepted for publication November 13, 2010.
Rarely, surgical treatment is indicated. Recently, neu-
limit our search to a specific time period. We focused
rostimulation has emerged as a therapeutic option for
on clinical efficacy and tolerability of the various
drugs and procedures based on data from human
We performed a PubMed search of the English
studies. We included the best available studies for
literature to find studies on the acute and prophylac-
each discussed drug or procedure. These ranged from
tic treatment of CH. Search terms were CH and each
randomized controlled trials for some treatments, to
of the following: acute treatment, prophylactic (or
preventive) treatment, triptans, oxygen, ergotamine,dihydroergotamine, lidocaine, somatostatin, oct-reotide, verapamil, lithium, topiramate, valproic acid,
TREATMENT OF THE ACUTE ATTACK
methysergide, gabapentin, baclofen, melatonin, botu-
(TABLE 1)
linum toxin, corticosteroids, neurostimulation, occipi-
Because the pain of acute CH attacks evolves
tal nerve block/stimulation, sphenopalatine ganglion
rapidly, oral medications are usually not as effective
block/stimulation, hypothalamic stimulation, radio-
for this purpose as they are for migraine attacks. For
rapid and effective pain control, the therapeutic agent
surgery, microvascular decompression. We did not
Table 1.—Drugs for the Acute Treatment of Cluster Headache
daily during a clusterperiod; contraindicated inpatients with CV diseases
contraindicated in patientswith CV diseases
contraindicated in patientswith CV diseases
contraindicated in patientswith CV diseases; cannotbe used with triptans
*See Appendix for detailed guidelines. AEs = adverse effects; CV = cardiovascular; EFNS = European Federation of Neurological Societies; IM = intramuscular;IN = intranasal; IV = intravenous; L/min = liters per minute; SC = subcutaneous. TRIPTANS
repeated use. The response to treatment of patients
The 5-HT1B/1D agonists (known as triptans), in an
who had chronic CH (CCH) was somewhat less
injectable or intranasal preparation, are a mainstay of
robust, and slower to occur, as compared with that of
ECH patients. Adverse effects were reported by 62%
Sumatriptan.—Sumatriptan, injected subcutane-
of patients. Withdrawal rate was 33%, with 4 (8%)
ously, is the drug of choice for acute CH attacks.1 The
patients withdrawing because of AEs.
efficacy of the drug for this indication was examined
The efficacy of intranasal sumatriptan in the
in a number of well-designed studies.4-7 In 1 random-
treatment of acute CH attacks was examined in 1
ized, placebo-controlled study the efficacy of subcu-
placebo controlled study.8 Patients with ECH or
taneous sumatriptan (6 mg) for acute CH treatment
CCH, whose attacks lasted at least 45 minutes, were
was examined.4 Data from 39 patients were evalu-
given intranasal sumatriptan 20 mg, or placebo. Data
ated. Headache severity decreased within 15 minutes
from 154 attacks, experienced by 118 patients, were
in a significantly higher proportion of sumatriptan-
analyzed. At 30 minutes after treatment, headache
treated, as compared with placebo-treated, attacks
(74% vs 26 %). Also, a significantly higher proportion
sumatriptan- compared with placebo-treated attacks
of sumatriptan-treated patients were pain free 15
(57% vs 26%). The corresponding pain-free rates at
minutes after injection, as compared with those who
that time were 47% and 18%. The drug was well
received placebo (46% vs 10%). Sumatriptan was
tolerated. Another study, that was open label,
well tolerated. In another controlled study, subcuta-
reported on lower efficacy of intranasal, as compared
neous sumatriptan at a dose of either 6 mg or 12 mg,
with subcutaneous sumatriptan, in acute CH treat-
or placebo, was given to 134 CH patients.5 Fifteen
ment.9 A limitation of that study, in addition to its
minutes after injection, the proportion of patients
open-label design, was the fact that treatment out-
who experienced headache relief was 80%, 75% and
comes were evaluated at a relatively early time point
35% for sumatriptan 12 mg, sumatriptan 6 mg, and
placebo, respectively. The higher dose of sumatriptan
In summary, injectable sumatriptan is effective
was not significantly superior to the lower dose, and
and well tolerated for the majority of CH patients.
was associated with more adverse effects (AEs). In an
The drug has a rapid onset of action. It remains well
open-label study from the same group, the long-term
tolerated and effective even when taken frequently
safety and efficacy of subcutaneous sumatriptan was
(up to twice daily) during a cluster period. The rec-
examined in 138 CH patients.6 Each patient treated a
ommended dose is 6 mg, although lower doses
maximum of 2 attacks per day with a single injection
(2-3 mg) may be effective in some patients.10 Intrana-
per attack. A total of 6353 attacks, that occurred over
sal sumatriptan appears to be less effective, and to
3 months, were evaluated. Headache relief was
have a slower onset of action than the injectable
obtained in 96% of attacks. There was no evidence for
decreased efficacy of the drug with continued use.
patients with coronary artery disease or cerebrovas-
Sumatriptan was well tolerated, and there was no
cular disease. Because CH typically afflicts middle
increase in AEs with higher frequency of using the
aged men, many of whom smoke, a clinical evalua-
drug. In another open-label study, the efficacy and
tion, oriented toward the risk of vascular diseases,
tolerability of sumatriptan in CH treatment were
needs to be done before prescribing the drug.
evaluated over a period of up to 1 year.7 The
Zolmitriptan.—The efficacy of intranasal zolmi-
maximum daily dose of sumatriptan was 12 mg. A
triptan for acute CH attacks has been studied in 2
total of 2031 attacks, experienced by 52 patients, were
controlled trials.11,12 In 1 study, 92 patients received
evaluated. In 88% of the attacks, treatment was effec-
either intranasal zolmitriptan (5 mg or 10 mg) or
tive within 15 minutes after injection, and 57% of
placebo, for acute attacks.11 Thirty minutes after treat-
patients were pain free at that time point. There was
ment, headache relief rates were significantly higher
no significant change in the efficacy of the drug with
for zolmitriptan compared with placebo (62%, 40%,
and 21% for zolmitriptan 10 mg, zolmitriptan 5 mg,
patients experienced significant pain relief within 15
and placebo, respectively). Patients with ECH had
minutes. The best response was observed in younger
higher response rates to zolmitriptan (and to
(<50 years old) patients who had ECH. Fogan exam-
placebo) compared with those who had CCH. Zolmi-
ined the efficacy of oxygen for acute CH in a double
triptan was well tolerated. In a similarly designed
blind crossover study.18 Nineteen men were treated
study, 52 CH patients treated 151 attacks with intra-
with either oxygen, or air inhalation, at a rate of
nasal zolmitriptan (10 mg or 5 mg) or placebo.12
6 L/min. After treatment, average pain relief score
Zolmitriptan, at both doses, was superior to placebo
was significantly higher for oxygen, as compared with
with regards to headache relief at 30 minutes (63%,
air. Rozen examined the effect of high flow oxygen on
50% and 30% for zolmitriptan 10 mg, zolmitriptan
CH pain in 3 patients who had been refractory to
5 mg, and placebo, respectively). The corresponding
oxygen given at the standard flow rate of 7-10 L/
pain-free rates at that time point were 47%, 39%, and
min.19 All 3 patients (2 with CCH and 1 with ECH)
20%. Zolmitriptan, at both doses, was well tolerated.
had complete or near-complete headache response
Oral zolmitriptan was evaluated as an acute
after inhaling 100% oxygen at a rate of 14-15 L/min.
treatment for CH attacks in a randomized controlled
Two of the patients were heavy smokers. The author
study.13 The drug was found to be superior to placebo
suggested that patients who fail to respond to oxygen
in ECH, but not CCH, patients. Thirty minutes after
at the standard flow rate should be tried on higher
treatment, headache response rates in ECH patients
flow. In a recent large controlled trial, Cohen et al
were 47% and 29%, for zolmitriptan 10 mg and
examined the efficacy of high flow oxygen in the treat-
ment of acute CH attacks.20 A total of 109 patients
In summary, intranasal zolmitriptan may be used
treated 4 CH attacks with either oxygen (12 L/min) or
for the acute treatment of CH, with comparable effi-
inhaled air, given via a facial mask for 15 minutes.
cacy to that of intranasal sumatriptan. Oral zolmitrip-
Oxygen was significantly superior to placebo with
tan has only limited efficacy for this purpose. As with
regards to the primary end point (elimination of pain
or “adequate pain relief” at 15 minutes—78% vs
patients with a history of cardiovascular or cere-
20%, with oxygen and air, respectively).
Hyperbaric oxygen (HBO) has also been studied
as a treatment for acute CH attacks.21,22 Weiss et al
treated a CH patient with hyperbaric (2 atmospheres)
Oxygen inhalation has been used for the treat-
100% oxygen, after she had been refractory to con-
ment of acute CH attacks for decades.1 The major
ventional oxygen therapy.21 Two attacks were treated
advantage of oxygen is the virtual lack of AEs. As
with HBO, with prompt and complete pain relief. Di
opposed to triptans, oxygen can be given to patients
Sabato et al treated 7 ECH patients with HBO in a
with a history of cardiovascular or cerebrovascular
placebo controlled study.22 Six patients responded
disease. The mechanism of action of oxygen on CH
well to treatment, with interruption of their attack.
has long been related to its vasoconstrictive effect.14
Moreover, in 3 of the responders the CH period
More recently, however, it has been shown that
ended after HBO treatment. Placebo treatment had
oxygen inhibits neuronal activation in the trigeminal
nucleus caudalis when this activation is initiated by
In summary, normobaric oxygen is an effective
stimulation of the parasympathetic outflow through
treatment of acute CH attacks in the majority of
the facial nerve.15 Oxygen has been evaluated as an
patients. It is well tolerated and has virtually no AEs.
acute treatment of CH in a number of studies.16 In an
As opposed to triptans, there is no limitation to the
open study, Kudrow examined the efficacy of oxygen
number of times per day it can be used. A proper
for acute CH attacks in 52 patients.17 Oxygen 100%
technique of use is crucial for good results with
was inhaled via a facial mask at a rate of 7 liters/
oxygen therapy. The patient should be instructed to
minute (L/min) for 15 minutes. Thirty-nine (75%)
use the oxygen via a non-rebreathable mask, at a rate
of 7-10 L/min, in a sitting position, for at least 15-20
studies that compared the various routes of adminis-
minutes. Patients may increase the flow rate up to
tration of the drug for CH. The efficacy and tolerabil-
15 L/min if needed. The optimal flow rate should be
ity of intranasal DHE (1 mg) in the treatment of
determined individually for each patient. The major
acute CH was examined in a controlled study of 25
disadvantage of oxygen therapy is its inconvenience
patients.24 Intranasal DHE decreased the intensity,
of use, particularly when the patient is out of home.
but not the duration, of the attacks, and was well
Portable oxygen tanks are available for patients who
tolerated. The authors suggested that the moderate
wish to use it in these circumstances. Oxygen therapy
efficacy of the drug in their study may have been
for CH should be used with caution, or even avoided,
related to the dose they used. They recommended
in patients with chronic obstructive pulmonary
that the drug be examined at a higher dose in future
disease, because of the risk of respiratory depression.
trials (the maximal recommended dose of intranasal
HBO may be considered for refractory CH patients.
DHE for acute headache treatment in adults is 2 mg).
However, because this is not a readily available
In summary, because of the moderate efficacy of
therapy, and there is no evidence for a sustained effect
most ergot preparations and the difficulty of receiving
of it on CH,23 the majority of patients are not likely to
intravenous DHE (probably the most effective
preparation for this purpose) in a timely manner, therole of ergots in the acute treatment of CH is limited. ERGOTAMINE AND DIHYDROERGOTAMINE LIDOCAINE
Ergot derivatives were among the first agents to
Data on the efficacy of locally applied lidocaine
be used in CH treatment. Reports on the efficacy of
on acute CH attacks are derived from several non-
ergotamine for this indication date back to the 1940s
controlled studies and 1 randomized controlled
and 1950s.1 These data, however, were based on small,
trial.25-28 Kittrelle et al examined the effect of
open-label studies and on case reports. The drug has
lidocaine, applied topically to the sphenopalatine
not been evaluated in controlled studies for this indi-
fossa, on acute CH attacks.25 Four of the 5 treated
cation. Kudrow compared the efficacy of sublingual
patients experienced rapid relief from pain and asso-
ergotamine with that of oxygen in 50 patients with
ciated symptoms of nitrate-induced CH attacks. The
CH.17 The response rate to ergotamine was 70%, as
treatment was also effective for spontaneous attacks.
compared with 82% for oxygen (with no significant
In another study, Hardebo and Elner examined the
between-group difference). Oxygen was better toler-
effect of lidocaine 4%, self-applied using a nasal
ated than ergotamine; however, the latter was more
dropper through the nostril ipsilateral to the pain, on
convenient to use. Because of limited availability and
CH pain and associated symptoms.26 Twenty-four
potentially serious AEs, most notably those related to
patients were studied, with moderately positive
the drug’s vasoconstrictive effect, ergotamine is cur-
results. Robbins examined the effect of intranasal
lidocaine, administered through a spray bottle, on
Dihydroergotamine (DHE) is available in inject-
pain in 30 men with ECH.27 Patients treated 2 con-
able (intravenous, intramuscular, or subcutaneous)
secutive CH attacks. Results were modest, with 27%
and intranasal formulations. Although no data from
reporting on “moderate relief,” 27% on “mild relief,”
controlled trials are available, clinical experience sug-
and 46% on no relief. In a placebo-controlled study,
gests efficacy of intravenous DHE for acute CH. This
Costa et al examined the efficacy of lidocaine 10%,
treatment, however, is not practical for the majority
applied bilaterally to the sphenopalatine fossa via
of patients because of the difficulty in receiving it
promptly with attack onset. Based on our clinical
nitroglycerin-induced CH attacks.28 Lidocaine appli-
experience, intramuscular and subcutaneous DHE
cation resulted in elimination of pain in all (15)
injections are not as effective as the intravenous
patients. However, there was a considerable delay (of
route, although, to our knowledge there are no
37 minutes on average) between the time of lidocaine
application and pain relief (the corresponding time
is alcohol. Patients should be advised to avoid alco-
interval for placebo was 59 minutes).
holic beverages during a cluster period (or, in the case
In summary, intranasal lidocaine is at best mod-
erately effective in the treatment of acute CH attacks. It should not be used as a first-line therapy for this
PROPHYLACTIC THERAPY
indication. This treatment may be used as adjunctive
Prophylactic therapy for CH is divided into main-
therapy in some patients whose attacks do not com-
tenance prophylaxis and transitional prophylaxis.
pletely respond to other, more effective, therapies.
throughout the entire course of the cluster period
SOMATOSTATIN AND OCTREOTIDE
with the intent of reducing the frequency and severity
Sicuteri et al conducted a controlled study to
of cluster attacks. When treating ECH, maintenance
examine the efficacy of intravenous somatostatin for
prophylactics are generally discontinued after resolu-
acute CH attacks.29 Seventy-two attacks, experienced
tion of the cluster period and then restarted at the
by 8 men, were studied. Somatostatin infusion was
onset of the next cluster period. Although mainte-
superior to placebo, and comparable to intramuscular
nance prophylaxis monotherapy is optimal, some
ergotamine, in relieving CH pain. Matharu et al
patients will require a combination of maintenance
evaluated the efficacy of octreotide, a somatostatin
medications for adequate control of CH. However,
analog that can be given subcutaneously, for acute
care must be taken to avoid potentially negative drug
CH.30 Octreotide 100 mg was significantly superior to
interactions. Transitional prophylactics are adminis-
placebo with regard to headache response rates (52%
tered for short durations as adjunctive therapies to
maintenance prophylactics in an attempt to abort the
An important advantage of these drugs is their
cluster period or to further reduce the frequency and
lack of vasoconstrictive effect, making them a viable
severity of cluster attacks. They are often begun
treatment option for patients who cannot use triptans
simultaneously with initiation of maintenance pro-
phylaxis because they tend to work more quickly andthus provide control of CH until the maintenance
SUMMARY—TREATMENT OF THE ACUTE ATTACK
In summary, injectable sumatriptan and inhaled
MAINTENANCE PROPHYLAXIS (TABLE 2)
oxygen are both a first-line therapy for acute CH. The
First-Line Therapy.—Verapamil, a calcium-channel
decision on which of these options to use should be
blocker, is the first-line maintenance prophylactic
made after considering the patient’s medical comor-
medication for CH. Verapamil is considered first-line
bidities and personal preference. In patients who do
therapy because of its efficacy, relative safety, and the
not respond well to these treatments (or in those who
ability to coadminister symptomatic and transitional
cannot use triptans), somatostatin or its analogs
therapies with less concern about drug interactions
appear to be a promising therapeutic option. Intrana-
compared with some of the other maintenance pro-
sal lidocaine may be tried as adjunctive therapy in
phylactic medications (eg, lithium carbonate). In
open-label studies, approximately 70% of ECH and
There are little data with regard to clinical
CCH patients have substantial improvement with
parameters that may predict response to the various
verapamil therapy.32 In a double-blind placebo-
acute CH treatments. In a prospective study of 246
controlled trial of verapamil for maintenance prophy-
CH patients, older age was a predictor for decreased
laxis of ECH, 15 patients were randomized to 120 mg
response to triptans, whereas nausea, vomiting, and
of verapamil 3 times daily while 15 subjects were
restlessness predicted decreased response to oxy-
randomized to placebo.33 During 2 weeks of treat-
gen.31 As opposed to migraine, there are few known
ment, 80% of patients receiving verapamil had a
triggers to the acute CH attack, most notable of which
greater than 50% reduction in headache frequency,
Table 2.—Maintenance Prophylactic Therapy for Cluster Headache
cognitive dysfunction, fatigue,dizziness, taste alteration
*See Appendix for detailed guidelines. AEs = adverse
including 4 patients who became attack free. Vera-
Target dosages of verapamil ranging from 200 mg
pamil took effect quickly, with one-half of responders
to 960 mg per day in divided doses are typically used
having substantial improvement within the first week
for cluster prophylaxis.35 Most patients will respond
and the other one-half responding during the second
to doses of 200 mg to 480 mg per day.36 Immediate or
week. Meanwhile, zero patients receiving placebo had
extended release formulations may be used. Slow
a greater than 50% reduction in headache frequency.
titrations up to the target dose may reduce AEs
Adverse effects due to verapamil were mild, with con-
including hypotension, constipation, and peripheral
stipation being the most common and most bother-
edema. A method of titrating and tapering verapamil
some. A double-blind, crossover study of verapamil vs
dosage in 40 mg intervals is described in a paper by
lithium carbonate for CCH suggests that verapamil is
Blau and Engel.36 EKG monitoring is necessary
a superior treatment.34 In this randomized trial, each
during verapamil therapy because of the risk of heart
of the 24 subjects received verapamil 360 mg per day
block and bradycardia, AEs that can develop with
or lithium carbonate 300 mg 3 times daily for 8 weeks,
initiation of therapy, increases in dose, and even
and then following a 2 week washout period was
during continued stable dose therapy.37 In our prac-
switched to the other therapy for an additional 8
tice, we obtain a baseline EKG before initiating vera-
weeks. Verapamil and lithium both provided similar
pamil therapy, repeat EKG with each increase in dose
reductions in both headache index and analgesic con-
of at least 80 mg, and an EKG each 3 months if the
sumption. However, verapamil worked more quickly,
dose has been unchanged. Patients should be
with over 50% of patients having significant improve-
informed of the possibility of developing gingival
ment in headache index within the first week com-
hyperplasia because of long-term use of verapamil.
pared with 37% of those taking lithium. Furthermore,
Second-Line Therapy.—Lithium carbonate is a
only 12% of those taking verapamil reported AEs
second-line therapy for maintenance prophylaxis of
compared with 29% of those taking lithium.
CH. We consider lithium as a second-line therapy
because of its potential for causing numerous AEs,
studies only.43,44 A double-blind placebo-controlled
the need for blood test monitoring during therapy,
study of sodium valproate did not support its efficacy;
and its potential for causing several drug interactions.
however, this may have been due to an exceedingly
Nonetheless, lithium carbonate has been demon-
high response rate of 62% in the placebo group.45
strated to provide significant benefit in the treatment
Effective doses range from 500 mg to 2000 mg daily in
of CCH. Its efficacy for treating CCH has been dem-
divided doses. Common AEs include weight gain,
onstrated in the investigation discussed in “First-Line
fatigue, tremor, hair loss, and nausea. Monitoring with
Therapy” and in a study of 8 additional CCH
complete blood counts and liver function tests are
patients.34,38 In the latter study, all 8 patients had at
necessary during valproic acid therapy. Limited evi-
least a 75% improvement within the first 2 weeks of
dence supports the use of melatonin for cluster pro-
therapy. However, only 1 of 3 who were followed
phylaxis. In a double-blind, placebo-controlled trial of
long-term had continued improvement after 18
10 mg melatonin, 5 of 10 subjects randomized to
months of therapy. The evidence for the utility of
melatonin had cluster remission within 5 days while
lithium carbonate for the treatment of ECH is less
none of the 10 subjects taking placebo went into
clear, with generally small studies providing contra-
remission.46 Open-label studies of gabapentin suggest
dictory results.34,38,39 Lithium carbonate doses of
its value in maintenance prophylaxis of CH in doses
600 mg to 900 mg per day are typically needed to
ranging from 800 mg to 3600 mg per day.47,48 Gaba-
obtain target therapeutic serum lithium levels of 0.4
pentin is typically a well-tolerated medication but
to 0.8 mEq/L. Lithium serum levels, renal function,
more common AEs include somnolence and fatigue,
and thyroid function should be monitored during
dizziness, weight gain, peripheral edema, and ataxia.
lithium therapy. Common AEs to lithium include
In a small open-label study of baclofen 10 mg 3 times
diarrhea, tremor and polyuria. Symptoms and signs of
daily, 6 of 9 subjects went into remission within 1
toxicity include nausea, vomiting, diarrhea, confusion,
week and an additional 1 subject had improvement
nystagmus, extrapyramidal signs, ataxia, and seizures.
followed by remission at week 2.49 Although adverse
Topiramate, in doses ranging from 50 mg to
events were not reported by subjects in this study,
200 mg per day, is considered second-line therapy for
more common AEs to baclofen include drowsiness,
CH prophylaxis. Although we have designated topi-
dizziness, ataxia, and muscle weakness. Clonidine,
ramate as second-line therapy, consistent with the
given as a 5 mg to 7.5 mg transdermal patch (that
Grade B recommendation in the European Federa-
delivers the drug at a rate of 0.2-0.3 mg daily for
tion of Neurological Societies guidelines, topiramate
1 week), has been studied in 2 small open-label
use for CH prophylaxis has been investigated in
studies.50,51 In the first, which included 8 ECH and 5
open-label studies only.40-42 Common AEs to topira-
CCH patients, there were significant reductions in
mate include cognitive dysfunction, paresthesias,
mean attack frequency, pain intensity, and attack
alteration in taste, weight loss, fatigue, and dizziness.
duration.50 However, a second study including 16
Patients with a history of nephrolithiasis should not
ECH patients failed to confirm these positive
receive topiramate because of an increased risk of
results.51 Tiredness and reduction in blood pressure
recurrent stones while taking this medication.
were AEs noted in these studies. An open-label study
Third-Line Therapy.—Other therapies that may be
of botulinum toxin type A as add-on therapy in 3
effective for maintenance cluster prophylaxis include
ECH and 9 CCH patients had mixed results.52 Fifty
methysergide, valproic acid, melatonin, gabapentin,
units injected ipsilateral to the headache resulted in
baclofen, clonidine, and botulinum toxin. Although
headache remission in 1 CCH patient, improvement
methysergide is likely effective for preventing CH, it
in attack frequency and severity in an additional 2
is not available in the USA and long-term use is asso-
CCH patients, improvement in a continuous baseline
ciated with fibrotic complications. Thus, we cannot
headache with no change in superimposed cluster
recommend its use. Valproic acid has been shown to
attacks in an additional 1 CCH patient, and no benefit
provide benefit in open-label and retrospective
in the remaining 8 patients. More common AEs to
botulinum toxin therapy include weakness of injected
trate, 3-4 mg per day in divided doses, may be admin-
muscles and pain at injection sites.
prophylaxis.58,61 Administration just before bedtime
TRANSITIONAL PROPHYLAXIS
may help to prevent nighttime attacks.
Corticosteroids are often prescribed concurrent
with initiation of maintenance prophylaxis in order to
INVASIVE PROCEDURES FOR CLUSTER
quickly obtain cluster control. Oral and intravenous
HEADACHE TREATMENT
corticosteroids may both provide benefit. Varying
With an individually tailored pharmacologic
doses of oral prednisone, ranging from 10 mg/day to
treatment plan, the majority of CH patients will
80 mg/day, were evaluated in a study of 9 episodic and
achieve satisfactory results. For those who remain
10 chronic cluster patients.53 Peak prednisone dose
refractory to medical treatment, a number of invasive
was given for 3 to 10 days and tapered over 10 to 30
procedures are available. These include peripheral
days. Complete relief from CH was seen in 11
nerve blocks, peripheral or central neurostimulation
patients, 3 had 50-99% relief, 3 had 25-50% relief, and
and, as a last resort, ablative surgery. Peripheral nerve
2 patients had no benefit. The ECH and CCH patients
block, mostly targeting the greater occipital nerve
had similar responses. Investigators observed that
(GON), may also be used in less refractory patients,
prednisone doses of 40 mg or higher were needed for
as an adjunct to pharmacologic therapy.
benefit. Headache recurrence was common duringthe prednisone taper. Other studies of oral pred-
PERIPHERAL NERVE AND
nisone have had similar results.54,55 Intravenous corti-
SPHENOPALATINE GANGLION BLOCK
costeroids, sometimes followed by oral steroids,
Efficacy of GON block in CH treatment was sug-
may also provide benefit for transitional cluster
gested by Anthony in the 1980s.62 More recently, the
therapy.56,57 A single high dose of intravenous meth-
procedure was investigated as CH treatment in a
ylprednisolone (30 mg/kg body weight over 3 hours)
number of studies, with the majority showing positive
delivered on the eighth day of an active cluster period
results.63-66 Peres et al evaluated the effect of GON
provided 10 of 13 treated patients with 2 or more days
block in 14 patients with CH.63 Patients received
of attack cessation.56 The mean interval between
GON block ipsilateral to the head pain using
steroid treatment and attack recurrence was 3.8 days.
lidocaine 1% and triamcinolone 40 mg. Patients were
Three patients had complete cluster remission.
evaluated before and 1 week after the block. Nine
Although adequate trials supporting their use are
(64%) patients had good or moderate response. The
lacking, ergotamine tartrate and DHE may be used
procedure was well tolerated. Ambrosini et al evalu-
for transitional prophylaxis.58,59 In an open-label
ated the effect of suboccipital injection of lidocaine
study, 23 ECH and 31 CCH patients were admitted to
2% with betamethasone, compared with lidocaine
the hospital for treatment with repetitive intravenous
and saline, in 23 CH patients in a randomized, con-
DHE.60 All patients became headache free while
trolled study.64 The CH attacks disappeared within 72
being treated with IV DHE: 10 patients (16%) after
hours in 85% of the lidocaine + betamethasone group
the first dose, an additional 12 (19%) during the first
(with 61% remaining attack free for 4 weeks) com-
day of hospitalization, and 22 (34%) more became
pared with none in the lidocaine + saline group. Injec-
headache free by the second day of hospitalization.
tions were well tolerated. Afridi et al examined the
By day 3, greater than 90% of patients were headache
efficacy of GON block, using lidocaine 2% and meth-
free and by day 5 all were headache free. At 3 months
ylprednisolone, in patients with refractory chronic
after discharge, >90% of ECH patients and 44% of
daily headache.65 Their sample included 19 patients
CCH patients remained headache free. Approxi-
with CH who received 22 injections. Thirteen of the
mately 83% of patients reported no AEs from IV
injections (59%) resulted in a complete or partial
DHE. Reported AEs included nausea, non-cardiac
response, with a median duration of 12 and 21 days,
chest tightness, and a metallic taste. Ergotamine tar-
for complete and partial response, respectively. In
contrast to these results, Busch et al reported on only
patients. Complications/AEs included lead migration,
minor headache improvement in 60% of 15 CH
painful paresthesias, muscle recruitment, neck stiff-
patients who received GON block using prilocaine.66
ness, skin pain, and infection. Mean battery life was
Endoscopically guided sphenopalatine ganglion
(SPG) blockade has been evaluated by Felisati et al
The SPG stimulation may also be an effective
for CH treatment.67 Of 20 refractory CCH patients
treatment for refractory CH. Five patients with CCH,
who underwent the procedure, 11 experienced signifi-
refractory to more conventional therapies, were
cant, albeit temporary, symptom relief.
treated with SPG stimulation during 18 acute clusterattacks.71 Stimulation resulted in complete attack
PERIPHERAL NERVE AND
resolution for 11 of the attacks, greater than 50%
SPHENOPALATINE GANGLION
reduction in pain severity without complete resolu-
STIMULATION
tion for 3 attacks, and minimal to no relief for 4
Peripheral nerve stimulation may be effective
attacks. Benefits from stimulation were noted within 1
and indicated for the prophylactic therapy of CCH
minute to 3 minutes of treatment initiation. Stimula-
patients who are refractory or intolerant to medica-
tion was well tolerated with only mild AEs from
tion therapy. Several small studies have now shown
stimulator placement, including transient epistaxis
occipital nerve stimulation (ONS) to be a promising
and transient mild facial pain. Further investigations
therapy for such patients. Eight patients with drug-
of SPG stimulation for the acute and prophylactic
resistant CCH, treated with unilateral ONS, were fol-
lowed for an average of 15.1 months.68 At the time oflast follow-up, 2 of 8 patients were pain free, 3 had a
DEEP BRAIN (HYPOTHALAMIC)
~90% reduction in headache frequency, 2 had ~40%
STIMULATION
reduction, and 1 patient derived no benefit. Two
Leone et al reported in 2001 on a 39-year-old
patients had side-shift of their cluster attacks requir-
man with intractable CH whose attacks improved sig-
ing treatment with suboccipital steroid injection.
nificantly after implantation of a stimulating elec-
Complications included electrode migration (n = 1),
trode to the posterior hypothalamus, ipsilateral to the
lead displacement after a fall (n = 1), and thoracic
pain.72 Since this first report, several studies have
discomfort or tingling (n = 2). Bilateral ONS was
been published on the efficacy and tolerability of
investigated in 8 patients with medically intractable
hypothalamic stimulation (HS) for CH.73-75 Schoenen
CH.69 At median follow-up of 20 months, subjective
et al examined the effect of unilateral HS in 6 refrac-
self-assessment of benefit was graded as substantial
tory CCH patients.73 Three patients had “excellent”
(Ն90%) in 2 patients, moderate (Ն40%) in 3, mild
results, while another had only a transient remission.
(Ն25%) in 1, and nil in 2 patients. Six patients
In 1 patient treatment had to be stopped because of
reported that they would recommend the use of ONS
AEs (autonomic disturbances and panic attacks), and
to other similar cluster patients. Complications, affect-
1 died of intracerebral hemorrhage shortly after the
ing 4 of the patients, included: excessive pain at inci-
procedure. Leone et al reported on the long-term
sion site (n = 1), electrode migration (n = 3), electrode
results of 16 previously refractory CCH patients who
fracture (n = 1), and shock-like sensation because of
had HS.74 At a mean follow-up of 23 months, major
kinking of wires (n = 1). In 2009, results from
improvement in pain, or complete pain elimination,
extended follow-up of these 8 patients and an addi-
was obtained in 13 (81%) patients. The mean time to
tional 6 patients treated with bilateral ONS were
headache benefit was 42 days. Overall, the procedure
reported.70 At a median follow-up of 17.5 months, 10
was well tolerated. No hormonal, affective or sleep-
of 14 patients reported improvement, including 3 with
related abnormalities were observed. One patient
>90% improvement, 3 with 40–60% improvement,
had an asymptomatic intracerebral hemorrhage that
and 4 with 20–30% improvement. Nine patients
subsequently resolved. Transient diplopia was a
stated that they would recommend ONS to other
common AE with high amplitude stimulation.
Bartsch et al reported on 6 CCH patients who under-
intermedius, has shown some efficacy in refractory
went HS.75 At a mean follow-up of 17 months, 3
CCH; however, response rate decreased over time.81
patients responded well to treatment, being almost
Gamma knife radiosurgery is a relatively recent
attack free, while 3 patients failed to respond. The
therapeutic approach for CH.82,83 Despite early
procedure was well tolerated. The authors concluded
encouraging results,82 more recent data showed only
that HS is effective in a subset of refractory CCH
modest long-term pain relief and high rate of AEs,
patients. Interestingly, in another study, HS was not
effective in the majority of patients when used as an
Another surgical approach for CH targets the
acute CH treatment, suggesting that this treatment
parasympathetic component of the disease, typically
affects CH through more complex pain modulating
by blocking or ablating the SPG.67,84,85 In 1 study,
radiofrequency blockade of the SPG was performed
In summary, HS is an emerging viable treatment
in 66 CH patients.84 Complete pain relief was
for refractory CCH. It appears to be effective in some,
achieved in 61% and 30% of ECH and CCH patients,
but not all, patients. Although the treatment is gener-
respectively. In a more recent study, 15 refractory
ally well tolerated, the risk of intraceberal hemor-
CCH patients were treated with radiofrequency abla-
rhage, and even death, should be kept in mind when
tion of the SPG.85 The treatment decreased signifi-
cantly the mean attack frequency, mean pain intensityand pain-related disability, and these effects lasted for12-18 months. ABLATIVE SURGICAL PROCEDURES
In summary, ablative surgical procedures should
With the emergence of a variety of pharmaco-
be reserved as the last resort for refractory CH
logic and non-pharmacologic therapies for CH, the
patients. The procedures that appear to be more
role of ablative surgery in this disease has declined.1
effective in the long-term management of the disease
Candidates for surgery should have strictly unilateral,
are radiofrequency trigeminal ganglion ablation and
side-locked, CH attacks. A number of procedures
trigeminal rhizotomy. It should be noted, however,
have been used with some success for this indication,
that CH attacks have been shown to persist after
including radiofrequency ablation of the trigeminal
trigeminal root section in a case report of man with
ganglion, trigeminal sensory rhizotomy, gamma knife
CH, supporting the hypothesis of a central pain gen-
surgery, and microvascular trigeminal nerve decom-
pression.1 Radiofrequency trigeminal gangliorhizoly-sis has been shown as effective in up to 75% ofrefractory CCH patients.78,79 In a case series of 27
APPENDIX
patients who underwent this procedure, 2 developed
European Federation of Neurological Societies
anesthesia dolorosa.79 Other complications included
(EFNS) guidelines—evidence classification scheme for a
corneal anesthesia, keratitis, and diplopia. Trigeminal
root section has been reported to be effective in 88%
Class I: An adequately powered prospective, ran-
of 17 patients with refractory CCH, with 76% expe-
domized, controlled clinical trial with masked outcome
assessment in a representative population or an
included corneal abrasion, masticatory muscle weak-
adequately powered systematic review of prospective
ness, anesthesia dolorosa and the development of CH
randomized controlled clinical trials with masked
on the other side. One patient, who underwent the
outcome assessment in representative populations. The
procedure twice, died after the second surgery. The
authors concluded that trigeminal nerve section is aviable therapeutic option for selected refractory CCH
patients. Microvascular decompression of the trigemi-
(b) Primary outcome(s) is/are clearly defined.
nal nerve, with or without section of the nervus
(c) Exclusion/inclusion criteria are clearly defined.
(d) Adequate accounting for dropouts and cross-
Category 2
overs with numbers sufficiently low to have
(a) Drafting the Manuscript
(e) Relevant baseline characteristics are presented
(b) Revising It for Intellectual Content
and substantially equivalent among treatment
groups or there is appropriate statistical adjust-
Category 3 (a) Final Approval of the Completed Article
study in a representative population with masked
REFERENCES
outcome assessment that meets a-e or a randomized,
controlled trial in a representative population that lacks
1. Matharu MS, Goadsby PJ. Trigeminal autonomic
Cephalalgias: Diagnosis and management. In: Silber-
stein SD, Lipton RB, Dodick DW, eds. Wolff’s Head-Class III: All other controlled trials (including well- ache and Other Head Pain, Eighth edn. New York:
defined natural history controls or patients serving as
Oxford University Press; 2008:379-430.
own controls) in a representative population, where
2. May A. Cluster headache: Pathogenesis, diagnosis,
outcome assessment is independent of patient treatment.
and management. Lancet. 2005;366:843-855. Class IV: Evidence from uncontrolled studies, case
3. Law S, Derry S, and Moore RA. Triptans for acute
series, case reports, or expert opinion.
cluster headache. Cochrane Database Syst Rev. 2010;4:CD008042. Rating of recommendations:
4. The Sumatriptan Cluster Headache Study Group.
Treatment of acute cluster headache with sumatrip-
Level A rating (established as effective, ineffective,
tan. N Engl J Med. 1991;325:322-326.
or harmful) requires at least 1 convincing class I study or
5. Ekbom K, Monstad I, Prusinski A, et al. Subcutane-
at least 2 consistent, convincing class II studies.
ous sumatriptan in the acute treatment of clusterheadache: A dose comparison study. The Sumatrip-
Level B rating (probably effective, ineffective, or
tan Cluster Headache Study Group. Acta Neurol
harmful) requires at least 1 convincing class II study or
6. Ekbom K, Krabbe A, Micieli G, et al. Cluster head-
Level C (possibly effective, ineffective, or harmful)
ache attacks treated for up to three months with
rating requires at least 2 convincing class III studies.
Cluster Headache Long-term Study Group. Ceph-
Adapted with permission from Brainin et al.
Guidance for the preparation of neurological manage-
7. Gobel H, Lindner V, Heinze A, et al. Acute therapy
ment guidelines by EFNS scientific task forces—revised
for cluster headache with sumatriptan: Findings of a
recommendations 2004. Eur J Neurol 2004;11:577-581.
one-year long-term study. Neurology. 1998;51:908-911.
8. van Vliet JA, Bahra A, Martin V, et al. Intranasal
sumatriptan in cluster headache: Randomized
STATEMENT OF AUTHORSHIP
placebo-controlled double-blind study. Neurology. 2003;60:630-633. Category 1
9. Hardebo JE, Dahlof C. Sumatriptan nasal spray
(a) Conception and Design
(20 mg/dose) in the acute treatment of cluster head-
ache. Cephalalgia. 1998;18:487-489. (b) Acquisition of Data
10. Gregor N, Schlesiger C, Akova-Ozturk E, et al.
Treatment of cluster headache attacks with less than
(c) Analysis and Interpretation of Data
6 mg subcutaneous sumatriptan. Headache. 2005;
11. Cittadini E, May A, Straube A, et al. Effectiveness
25. Kittrelle JP, Grouse DS, Seybold ME. Cluster head-
of intranasal zolmitriptan in acute cluster headache:
ache. Local anesthetic abortive agents. Arch Neurol.
A randomized, placebo-controlled, double-blind
26. Hardebo JE, Elner A. Nerves and vessels in the
pterygopalatine fossa and symptoms of cluster head-
12. Rapoport AM, Mathew NT, Silberstein SD, et al.
ache. Headache. 1987;27:528-532.
Zolmitriptan nasal spray in the acute treatment of
27. Robbins L. Intranasal lidocaine for cluster head-
cluster headache: A double-blind study. Neurology.
ache. Headache. 1995;35:83-84.
28. Costa A, Pucci E, Antonaci F, et al. The effect of
13. Bahra A, Gawel MJ, Hardebo JE, et al. Oral zolmi-
intranasal cocaine and lidocaine on nitroglycerin-
triptan is effective in the acute treatment of cluster
induced attacks in cluster headache. Cephalalgia.
headache. Neurology. 2000;54:1832-1839.
14. Drummond PD, Anthony M. Extracranial vascular
29. Sicuteri F, Geppetti P, Marabini S, et al. Pain relief
responses to sublingual nitroglycerin and oxygen
by somatostatin in attacks of cluster headache. Pain.
inhalation in cluster headache patients. Headache.
30. Matharu MS, Levy MJ, Meeran K, et al. Subcutane-
15. Akerman S, Holland PR, Lasalandra MP, et al.
ous octreotide in cluster headache: Randomized
Oxygen inhibits neuronal activation in the trigemi-
placebo-controlled double-blind crossover study.
nocervical complex after stimulation of trigeminal
autonomic reflex, but not during direct dural activa-
31. Schurks M, Rosskopf D, de Jesus J, et al. Predictors
tion of trigeminal afferents. Headache. 2009;49:1131-
of acute treatment response among patients with
cluster headache. Headache. 2007;47:1079-1084.
16. Bennett MH, French C, Schnabel A, et al. Nor-
32. Gabai IJ, Spierings ELH. Prophylactic treatment
of cluster headache with verapamil. Headache.
migraine and cluster headache. Cochrane Database
33. Leone M, D’Amico D, Frediani F, et al. Verapamil
17. Kudrow L. Response of cluster headache attacks to
in the prophylaxis of episodic cluster headache:
oxygen inhalation. Headache. 1981;21:1-4.
A double-blind study versus placebo. Neurology.
18. Fogan L. Treatment of cluster headache. A double-
blind comparison of oxygen v air inhalation. Arch
34. Bussone G, Leone M, Peccarisi C, et al. Double
blind comparison of lithium and verapamil in
19. Rozen TD. High oxygen flow rates for cluster head-
cluster headache prophylaxis. Headache. 1990;30:
ache. Neurology. 2004;63:593.
20. Cohen AS, Burns B, and Goadsby PJ. High-flow
35. Tfelt-Hansen P, Tfelt-Hansen J. Verapamil for
oxygen for treatment of cluster headache: A ran-
cluster headache. Clinical pharmacology and pos-
domized trial. JAMA. 2009;302:2451-2457.
sible mode of action. Headache. 2009;49:117-125.
21. Weiss LD, Ramasastry SS, and Eidelman BH. Treat-
36. Blau JN, Engel HO. Individualizing treatment with
ment of a cluster headache patient in a hyperbaric
verapamil for cluster headache patients. Headache.
chamber. Headache. 1989;29:109-110.
22. Di Sabato F, Fusco BM, Pelaia P, et al. Hyperbaric
37. Cohen AS, Matharu MS, and Goadsby PJ. Electro-
oxygen therapy in cluster headache. Pain. 1993;
cardiographic abnormalities in patients with cluster
headache on verapamil therapy. Neurology. 2007;
23. Nilsson Remahl AI, Ansjon R, Lind F, et al. Hyper-
baric oxygen treatment of active cluster headache: A
38. Ekbom K. Lithium for cluster headache: Review of
double-blind placebo-controlled cross-over study.
the literature and preliminary results of long-term
Cephalalgia. 2002;22:730-739.
treatment. Headache. 1981;21:132-139.
24. Andersson PG, Jespersen LT. Dihydroergotamine
39. Steiner TJ, Hering R, Couturier EGM, et al.
nasal spray in the treatment of attacks of cluster
Double-blind placebo-controlled trial of lithium in
headache.A double-blind trial versus placebo. Ceph-
episodic cluster headache. Cephalalgia. 1997;17:673-
40. Wheeler SD, Carrazana EJ. Topiramate-treated
55. Jammes JL. The treatment of cluster headaches with
cluster headache. Neurology. 1999;53:234-236.
prednisone. Dis Nerv Syst. 1975;36:375-376.
41. Pascual J, Lainez MJ, Dodick D, et al. Antiepileptic
56. Antonaci F, Costa A, Candeloro E, et al. Single
drugs for the treatment of chronic and episodic
high-dose steroid treatment in episodic cluster head-
cluster headache: A review. Headache. 2007;47:81-
ache. Cephalalgia. 2005;25:290-295.
57. Mir P, Alberca R, Navarro A, et al. Prophylactic
42. May A, Leone M, Afra J, et al. EFNS guidelines on
treatment of episodic cluster headache with intrave-
the treatment of cluster headache and other
nous bolus of methylprednisolone. Neurol Sci.
trigeminal-autonomic cephalalgias. Eur J Neurol.
58. Halker R, Vargas B, and Dodick DW. Cluster head-
43. Hering R, Kuritzky A. Sodium valproate in the
ache: Diagnosis and treatment. Semin Neurol.
treatment of cluster headache: An open clinical trial.
59. Leone M, Franzini A, Cecchini AP, et al. Cluster
44. Gallagher RM, Mueller LL, and Freitag FG. Dival-
headache: Pharmacological treatment and neuro-
proex sodium in the treatment of migraine and
stimulation. Nat Clin Pract Neurol. 2009;5:153-162.
cluster headaches. J Am Osteopath Assoc. 2002;102:
60. Mather PJ, Silberstein SD, Schulman EA, et al. The
treatment of cluster headache with repetitive intra-
45. El Amrani M, Massiou H, and Bousser MG. A nega-
venous dihydroergotamine. Headache. 1991;31:525-
tive trial of sodium valproate in cluster headache:
Methodological issues. Cephalalgia. 2002;22:205-
61. Ekbom K, Hardebo JE. Cluster headache:Aetiology,
diagnosis and management. Drugs. 2002;62:61-69.
46. Leone M, D’Amico D, Moschiano F, et al. Melato-
62. Anthony M. Arrest of attacks of cluster by local
nin versus placebo in the prophylaxis of cluster
steroid injection of the occipital nerve; clinical and
headache: A double-blind pilot study with parallel
research advances: Proceedings of the 5th Interna-
groups. Cephalalgia. 1996;16:494-496.
tional Migraine Symposium, London, September
47. Leandri M, Luzzani M, Cruccu G, et al. Drug-
19-20, 1984. In: Clifford Rose F, ed. Migraine. Basel:
resistant cluster headache responding to gabapen-
tin: A pilot study. Cephalalgia. 2001;21:744-746.
63. Peres MF, Stiles MA, Siow HC, et al. Greater occipi-
48. Schuh-Hofer S, Israel H, Neeb L, et al. The use of
tal nerve blockade for cluster headache. Cephalal-
gabapentin in chronic cluster headache patients
refractory to first-line therapy. Eur J Neurol.
64. Ambrosini A, Vandenheede M, Rossi P, et al. Sub-
occipital injection with a mixture of rapid- and long-
49. Hering-Hanit R, Gadoth N. Baclofen in cluster
acting steroids in cluster headache: A double-blind
headache. Headache. 2000;40:48-51.
placebo-controlled study. Pain. 2005;118:92-96.
50. D’Andrea G, Perini F, Granella F, et al. Efficacy of
65. Afridi SK, Shields KG, Bhola R, et al. Greater
transdermal clonidine in short-term treatment of
occipital nerve injection in primary headache syn-
cluster headache: A pilot study. Cephalalgia. 1995;
dromes - prolonged effects from a single injection.
51. Leone M, Attanasio A, Grazzi L, et al. Transdermal
66. Busch V, Jakob W, Juergens T, et al. Occipital nerve
clonidine in the prophylaxis of episodic cluster head-
blockade in chronic cluster headache patients and
ache: An open study. Headache. 1997;37:559-560.
functional connectivity between trigeminal and
52. Sostak P, Krause P, Forderreuther S, et al. Botuli-
occipital nerves. Cephalalgia. 2007;27:1206-1214.
num toxin type-A therapy in cluster headache: An
67. Felisati G, Arnone F, Lozza P, et al. Sphenopalatine
open study. J Headache Pain. 2007;8:236-241.
endoscopic ganglion block: A revision of a tradi-
53. Couch JR Jr, and Ziegler DK. Prednisone therapy
tional technique for cluster headache. Laryngo-
for cluster headache. Headache. 1978;18:219-221.
54. Kudrow L. Comparative results of prednisone,
68. Magis D, Allena M, Bolla M, et al. Occipital nerve
methysergide and lithium therapy in cluster head-
stimulation for drug-resistant chronic cluster head-
ache. In: Greene R, ed. Current Concepts in Migraine
ache: A prospective pilot study. Lancet Neurol.Research. New York: Raven Press; 1978:159-163.
69. Burns B, Watkins L, and Goadsby PJ. Treatment of
78. Onofrio BM, Campbell JK. Surgical treatment of
medically intractable cluster headache by occipital
chronic cluster headache. Mayo Clin Proc. 1986;
nerve stimulation: Long-term follow-up of eight
patients. Lancet. 2007;369:1099-1106.
79. Mathew NT, Hurt W. Percutaneous radiofrequency
70. Burns B, Watkins L, and Goadsby PJ. Treatment of
trigeminal gangliorhizolysis in intractable cluster
intractable chronic cluster headache by occipital
headache. Headache. 1988;28:328-331.
nerve stimulation in 14 patients. Neurology. 2009;72:
80. Jarrar RG, Black DF, Dodick DW, et al. Outcome of
trigeminal nerve section in the treatment of chronic
71. Ansarinia M, Rezai A, Tepper SJ, et al. Electrical
cluster headache. Neurology. 2003;60:1360-1362.
stimulation of sphenopalatine ganglion for acute
81. Lovely TJ, Kotsiakis X, and Jannetta PJ. The surgical
treatment of cluster headaches. Headache. 2010;50:
management of chronic cluster headache. Headache.
72. Leone M, Franzini A, and Bussone G. Stereotactic
82. Ford RG, Ford KT, Swaid S, et al. Gamma knife
stimulation of posterior hypothalamic gray matter in
treatment of refractory cluster headache. Headache.
a patient with intractable cluster headache. N Engl J
83. Donnet A, Tamura M, Valade D, et al. Trigeminal
73. Schoenen J, Di Clemente L, Vandenheede M, et al.
nerve radiosurgical treatment in intractable chronic
Hypothalamic stimulation in chronic cluster head-
cluster headache: Unexpected high toxicity. Neuro-
ache: A pilot study of efficacy and mode of action.
84. Sanders M, Zuurmond WW. Efficacy of sphenopa-
74. Leone M, Franzini A, Broggi G, et al. Hypothalamic
latine ganglion blockade in 66 patients suffering
stimulation for intractable cluster headache: Long-
from cluster headache: A 12- to 70-month follow-up
term experience. Neurology. 2006;67:150-152.
evaluation. J Neurosurg. 1997;87:876-880.
75. Bartsch T, Pinsker MO, Rasche D, et al. Hypotha-
85. Narouze S, Kapural L, Casanova J, et al. Sphenopa-
lamic deep brain stimulation for cluster headache:
latine ganglion radiofrequency ablation for the man-
Experience from a new multicase series. Cephalal-
agement of chronic cluster headache. Headache.
76. Leone M, Franzini A, Broggi G, et al. Acute hypo-
86. Matharu MS, Goadsby PJ. Persistence of attacks of
thalamic stimulation and ongoing cluster headache
cluster headache after trigeminal nerve root section.
attacks. Neurology. 2006;67:1844-1845.
77. Leone M, Proietti CA, Franzini A, et al. Lessons
87. Brainin M, Barnes M, Baron JC, et al. Guidance for
from 8 years’ experience of hypothalamic stimula-
the preparation of neurological management guide-
tion in cluster headache. Cephalalgia. 2008;28:787-
lines by EFNS scientific task forces—revised recom-
mendations 2004. Eur J Neurol. 2004;11:577-581.
CONVOCATORIA Y DATOS GENER ALES DEL PROCE SO DE CONTRATACI ÓN S ERVICIO MUNIC IP AL DE AGUA P OTABLE Y AL CANT ARILLADO SANIT ARIO DE C OCHABAMBA - SEMAPA 1. CONV OCATOR IA Se convoca a la p resen tación de p ropuestas para el sig uiente proceso : S ERV ICIO MUNIC IPA L DE AGU A PO TAB LE Y AL CAN TAR ILLA DO S ANIT ARI O DE En tidad Convocan te : CO CHA BAMB A Mo d
Kidney Disease in Cats Chronic kidney (renal) disease is a relatively common disorder in cats, especially geriatric cats. Renal insufficiency (CRI) or renal failure (CRF) occurs when the kidneys are no longer able to perform their normal function of removing waste products from the blood. The former is the early stage of the latter. Kidney failure is not the same as the inability to make ur