Sphenopalatine Ganglion (SPG): Stimulation Mechanism, Safety, and Efficacy

Abstract

Objective.-To describe the history of and available data on sphenopalatine ganglion (SPG) neuromodulation in the treatment of headache up to the present.Background.-The SPG has been a therapeutic target to treat primary headache disorders for over 100 years. Multiple destructive lesions have also been tried with variable rate and duration of success. Neurostimulation of the SPG for cluster headache was first described in 2007.Methods.-This is not a systematic review. The authors review the anatomy and pathophysiology of the SPG and cluster headache and the important clinical trials, relating a history of how SPG neuromodulation reached the current state of approval in the European Union (EU) and pivotal registration study for cluster headache in the US.Results.-The EU approved SPG stimulation for cluster headache with a CE Mark in February of 2012. Since then, several EU countries have elected to reimburse implantation for cluster headache, and over 300 patients have been implanted worldwide.Conclusions.-Success rates for implanted SPG neuromodulation in the experimental phase of the European randomized controlled trial, in the open label extension trial, and in the registry of patients implanted outside of the trial remain at about two-thirds of patients implanted being responders, defined as being able to terminate at least 50% of attacks or having at least a 50% decrease in attack frequency or both. A US pivotal registration study is underway to confirm these results and obtain FDA approval for this treatment for cluster headache patients. Further studies in migraine are also underway.

Radiological anatomy assessment of the fissura pterygomaxillaris for a surgical approach to ganglion pterygopalatinum

“…). The SPG neurostimulator contains an integral lead that is placed within the PPF proximate to the SPG, and has been designed for implants through a gingival buccal incision (Tepper & Caparso, ).…”

“…For this new device (implantable ganglion pterygopalatinum stimulator), which has no external wires and does not require an internal battery, its replacement has been developed by a team of engineers led by Caparso, and the surgical approach with the necessary tools for implants has been created by a team led by Papay at the Cleveland Clinic (Assaf et al 2016). The SPG neurostimulator contains an integral lead that is placed within the PPF proximate to the SPG, and has been designed for implants through a gingival buccal incision (Tepper & Caparso, 2017).…”

“…). SPG neuromodulation is a flexible reversible technique by which electrical impulses inhibit the neuronal function, and could abort or prevent those efferent pathways that activate primary headache pain mechanisms, and associated autonomic signs and symptoms (Tepper & Caparso, ). Recently, invasive SPG neuromodulation has been introduced as one of the most effective treatments for chronic intractable primary headaches (Kohlmeier et al.…”

“…The SPG has been a therapeutic target for over 100 years (Sluder, 1908), and it is well known that it plays an important role in various pain syndromes (Piagkou et al 2011). SPG neuromodulation is a flexible reversible technique by which electrical impulses inhibit the neuronal function, and could abort or prevent those efferent pathways that activate primary headache pain mechanisms, and associated autonomic signs and symptoms (Tepper & Caparso, 2017). Recently, invasive SPG neuromodulation has been introduced as one of the most effective treatments for chronic intractable primary headaches (Kohlmeier et al 2017;L ainez & Guillam on, 2017;Leone & Cecchini, 2017;Puledda & Goadsby, 2017).…”

Chronic Headache and Neuromodulation

“…The noninvasive options include transcranial stimulation either electric [8][9][10] or magnetic [11][12][13] and transdermal stimulation of occipital [14,15], supraorbital [9,[14][15][16][17][18][19] or vagus [20][21][22][23] nerves. Invasive procedures include stimulation of occipital [5,17,24,[25][26][27][28][29][30][31][32][33][34][35], supraorbital [19,31,36], infraorbital [31] or greater auricular [37] nerves as well as sphenopalatine ganglion [38][39][40][41][42][43][44], cervical spinal cord [45][46][47][48...…”