title: Electrical stimulation of sphenopalatine ganglion for acute treatment of cluster headaches.
abstract: BACKGROUND
  Cluster headaches (CH) are primary headaches marked by repeated short-lasting attacks of severe, unilateral head pain and associated autonomic symptoms. Despite aggressive management with medications, oxygen therapy, nerve blocks, as well as various lesioning and neurostimulation therapies, a number of patients are incapacitated and suffering. The sphenopalatine ganglion (SPG) has been implicated in the pathophysiology of CH and has been a target for blocks, lesioning, and other surgical approaches. For this reason, it was selected as a target for an acute neurostimulation study.
  
  
  METHODS
  Six patients with refractory chronic CH were treated with short-term (up to 1 hour) electrical stimulation of the SPG during an acute CH. Headaches were spontaneously present at the time of stimulation or were triggered with agents known to trigger clusters headache in each patient. A standard percutaneous infrazygomatic approach was used to place a needle at the ipsilateral SPG in the pterygopalatine fossa under fluoroscopic guidance. Electrical stimulation was performed using a temporary stimulating electrode. Stimulation was performed at various settings during maximal headache intensity.
  
  
  RESULTS
  Five patients had CH during the initial evaluation. Three returned 3 months later for a second evaluation. There were 18 acute and distinct CH attacks with clinically maximal visual analog scale (VAS) intensity of 8 (out of 10) and above. SPG stimulation resulted in complete resolution of the headache in 11 attacks, partial resolution (>50% VAS reduction) in 3, and minimal to no relief in 4 attacks. Associated autonomic features of CH were resolved in each responder. Pain relief was noted within several minutes of stimulation.
  
  
  CONCLUSIONS
  Sphenopalatine ganglion stimulation can be effective in relieving acute severe CH pain and associated autonomic features. Chronic long-term outcome studies are needed to determine the utility of SPG stimulation for management and prevention of CH.
authors.affiliation: The Headache Specialists, Las Vegas, NV, USA.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Ansarinia
authors.forename: Ali
authors.initials: A
authors.lastname: Rezai
authors.forename: Stewart J
authors.initials: SJ
authors.lastname: Tepper
authors.forename: Charles P
authors.initials: CP
authors.lastname: Steiner
authors.forename: Jenna
authors.initials: J
authors.lastname: Stump
authors.forename: Michael
authors.initials: M
authors.lastname: Stanton-Hicks
authors.forename: Andre
authors.initials: A
authors.lastname: Machado
authors.forename: Samer
authors.initials: S
authors.lastname: Narouze
mesh_terms: D000328:Adult; D003027:Cluster Headache / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D004599:Electric Stimulation Therapy / Q000009:adverse effects / Q000379:methods*; D005156:Facial Neuralgia / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D005726:Ganglia, Parasympathetic / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D056739:Pterygopalatine Fossa / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000601:surgery; D011859:Radiography; D055815:Young Adult