Evidence map›Paper›PMID 34384347›Full record

ArticleThe journal of headache and pain2021

Regional cerebral blood flow as predictor of response to occipital nerve block in cluster headache.

Sonia Medina, Norazah Abu Bakar, Owen O'Daly, Sarah Miller, Elena Makovac, Tara Renton, Steve C R Williams, Manjit Matharu, Matthew A Howard

Open access · goldAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in The journal of headache and pain, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed, 2 pooled it
1.5field-weighted citation impact, top 18% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 2 syntheses or guidelines pooled it, 12 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
  3. Trial
  4. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors at 2 institutions in 1 country.

Sonia Medina *Department of Neuroimaging, King's College London, Institute of Psychiatry, Psychology and Neuroscience, Box 89, De Crespigny Park, London, SE5 8AF, UK. Sonia.medina@kcl.ac.uk.ORCID http://orcid.org/0000-0001-8883-6520
Norazah Abu Bakar *Department of Oral Surgery, King's College London, London, UK.
Owen O'DalyDepartment of Neuroimaging, King's College London, Institute of Psychiatry, Psychology and Neuroscience, Box 89, De Crespigny Park, London, SE5 8AF, UK.
Sarah MillerHeadache and Facial Pain Group, UCL Queen Square Institute of Neurology, Queen Square, London, UK.
Elena MakovacDepartment of Neuroimaging, King's College London, Institute of Psychiatry, Psychology and Neuroscience, Box 89, De Crespigny Park, London, SE5 8AF, UK.
Tara RentonDepartment of Oral Surgery, King's College London, London, UK.
Steve C R WilliamsDepartment of Neuroimaging, King's College London, Institute of Psychiatry, Psychology and Neuroscience, Box 89, De Crespigny Park, London, SE5 8AF, UK.
Manjit Matharu *Headache and Facial Pain Group, UCL Queen Square Institute of Neurology, Queen Square, London, UK.
Matthew A Howard *Department of Neuroimaging, King's College London, Institute of Psychiatry, Psychology and Neuroscience, Box 89, De Crespigny Park, London, SE5 8AF, UK.
King's College London · GBNational Hospital for Neurology and Neurosurgery · GB

Funding

Medical Research Council MR/N026969/1
6 · The paper itself

Abstract

backgroundCluster headache is an excruciating disorder with no cure. Greater occipital nerve blockades can transiently suppress attacks in approximately 50% of patients, however, its mechanism of action remains uncertain, and there are no reliable predictors of treatment response. To address this, we investigated the effect of occipital nerve blockade on regional cerebral blood flow (rCBF), an index of brain activity, and differences between treatment responders and non-responders. Finally, we compared baseline perfusion maps from patients to a matched group of healthy controls.

methods21 male, treatment-naive patients were recruited while in a cluster headache bout. During a pain-free phase between headaches, patients underwent pseudo-continuous arterial spin labelled MRI assessments to provide quantitative indices of rCBF. MRIs were performed prior to and 7-to-21 days following treatment. Patients also recorded the frequency of their headache attacks in a daily paper diary. Neuropsychological assessment including anxiety, depression and quality of life measures was performed in a first, scanning free session for each patient.

resultsFollowing treatment, patients demonstrated relative rCBF reductions in posterior temporal gyrus, cerebellum and caudate, and rCBF increases in occipital cortex. Responders demonstrated relative rCBF increases, compared to non-responders, in medial prefrontal cortex and lateral occipital cortex at baseline, but relative reductions in cingulate and middle temporal cortices. rCBF was increased in patients compared to healthy controls in cerebellum and hippocampus, but reduced in orbitofrontal cortex, insula and middle temporal gyrus.

conclusionsWe provide new mechanistic insights regarding the aetiology of cluster headache, the mechanisms of action of occipital nerve blockades and potential predictors of treatment response. Future investigation should determine whether observed effects are reproducible and extend to other headache disorders.

Indexed as

Cluster HeadacheNerve BlockCerebrovascular CirculationHumansMaleQuality of LifeRegional Blood FlowSpin LabelsSpin LabelsArterial spin LabellingCluster headacheGreater occipital nerve blockRegional cerebral blood flowTrigeminal cephalgia

Identifiers

PMID34384347
PMCPMC8359299
OpenAlexW3187780260

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.