Refined sphenopalatine ganglion stimulator placement and intensity setting to augment blood flow and neurologic function

Jeffrey L. Saver*, Nino Kharaishvili, Tamar Janelidze, Maia Beridze, Natia Zarqua, Yoram Solberg, Natan M. Bornstein

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Background and Purpose-Two large, randomized trials indicated that sphenopalatine ganglion (SPG) stimulation improvesfinal disability outcome in acute anterior circulation patients with ischemic stroke with confirmed cortical involvement.This study evaluated 2 refinements in SPG stimulation treatment technique: (1) SPG electrode placement with real-timeoptical tracking guidance; and (2) stimulation intensity comfortable tolerance level selection using non-noxious facialphysiological markers.Methods-This study was a single, active arm trial at 4 centers, enrolling patients with anterior circulation ischemic stroke,National Institutes of Health Stroke Scale 1 to 6 including arm weakness subitem score =1, not receiving recanalizationtherapies, and within 24 hours of onset. Stimulation level was set based on ipsilateral facial tingling sensation orlacrimation. SPG stimulation effects were assessed by measuring volumetric blood flow in the ipsilateral common carotidartery by ultrasound and grasp and pinch strength in the affected hand before and during stimulation, and by change inNational Institutes of Health Stroke Scale from day 1 to 7.Results-Among 50 enrolled patients, age was median 66 years (interquartile range, 60-74), 44% were female, NationalInstitutes of Health Stroke Scale median was 5 (interquartile range, 4-5), and median onset-to-screening time was 18hours (interquartile range, 9-20). Median implantation skin-to-skin time was 4 minutes (interquartile range, 3-7), andall 50 implants were placed correctly. Comfortable tolerance level was found based on physiological biomarkers in 96%of patients, including 86% in the optimal, low-medium intensity range. SPG stimulation significantly increased commoncarotid artery peak systolic and end-diastolic blood flow (44%, P<0.0001; and 52%, P<0.0001) and improved pinchstrength (42%, P<0.0001) and grasp strength (26%, P<0.0001). Degree of National Institutes of Health Stroke Scalerecovery by day 7 was greater than in matched historic controls, median 75% versus 50%, P=0.0003.Conclusions-SPG stimulator placement with real-time optical tracking guidance was fast and accurate, and selection ofstimulation intensity levels based on non-noxious facial tingling and lacrimation was feasible in nearly all patients. SPGstimulation led to cervico-cranial blood flow augmentation and improved hand motor function.Clinical Trial Registration-URL: Unique identifier: NCT03551093.

Original languageEnglish
Pages (from-to)3512-3518
Number of pages7
Issue number12
StatePublished - 1 Dec 2019
Externally publishedYes


FundersFunder number
BrainsGate Ltd


    • Biomarker
    • Collateral circulation
    • Electrode
    • Ganglia
    • Hand Strength
    • Nasolacrimal duct
    • Pinch strength


    Dive into the research topics of 'Refined sphenopalatine ganglion stimulator placement and intensity setting to augment blood flow and neurologic function'. Together they form a unique fingerprint.

    Cite this