Trigeminal and sphenopalatine ganglion stimulation for intractable craniofacial pain--case series and literature review

Radiofrequency regulation of the sphenopalatine ganglion in managing herpes zoster ophthalmicus neuralgia: A case series

INTRODUCTION

Trigeminal herpes zoster, which comprises 10% to 20% of cases of herpes zoster, often leads to severe pain in the ophthalmic branches. Current treatments, including drug therapy and minimally invasive interventions, have limitations; accordingly, there is a need to explore alternative approaches. This study aimed to evaluate the efficacy and safety of computerized tomography (CT)-guided pulsed radiofrequency of the sphenopalatine ganglion in patients with intractable trigeminal herpetic pain.

PATIENT CONCERNS

Three patients with intractable trigeminal ophthalmic zoster neuralgia were studied. All patients complained of bursts of headache, which occurred at least 10 times a day, usually in the periorbital and frontal regions. Conventional treatments, including oral medications and radiofrequency therapy targeting the trigeminal-semilunar ganglion and supraorbital nerve, could not sufficiently provide relief.

DIAGNOSIS

Two patients were diagnosed with herpes zoster in the ocular branch of the trigeminal nerve with conjunctivitis, while one patient was diagnosed with postherpetic neuralgia in the ocular branch of the trigeminal nerve.

INTERVENTIONS

This study employed a novel approach that involved CT-guided radiofrequency regulation of the pterygopalatine fossa sphenopalatine ganglion.

OUTCOMES

In all three patients, pain relief was achieved within 1 to 3 days after treatment. During the follow-up, one patient had pain recurrence; however, its severity was ≈ 40% lower than the pretreatment pain severity. The second patient had sustained and effective pain relief. However, the pain of the third patient worsened again after 2 months. The average follow-up duration was 3 months. None of the enrolled patients showed treatment-related adverse reactions or complications.

CONCLUSION

Our findings indicated that CT-guided radiofrequency regulation of the pterygopalatine fossa sphenopalatine ganglion was a safe and effective intervention for pain in patients with trigeminal ophthalmic zoster neuralgia, suggesting that it may be a therapeutic option if other treatments fail.

Gasserian ganglion stimulation for refractory trigeminal neuropathic pain

BACKGROUND AND OBJECTIVE

Painful trigeminal neuropathy is a complex clinical entity due to its severity and refractoriness to pharmacological and interventional management. We describe our experience in treating refractory painful trigeminal neuropathy (RPTN) with gasserian ganglion stimulation (GGS).

MATERIALS AND METHODS

Six patients with RPTN were treated with GGS in our Unit between 2019 and 2022. The following data were collected: socio-demographic characteristics, triggering event, duration of the disease and treatment received prior to surgery, pre- and post-intervention visual analogue scale (VAS) score, follow-up time, and pre- and post-intervention functionality and quality of life.

RESULTS

All patients were women who had received aggressive first-, second-, and third-line pharmacological, non-pharmacological, and interventional management before being referred for GGS. Patients reported a 50%-72% decrease in pain on VAS and improved functionality during follow-up.

CONCLUSIONS

GGS is a promising therapeutic alternative for patients with RPTN. Although the initial outcomes and experience are encouraging, RPTN is recommended on the basis of safety, reproducibility, and trends observed in clinical practice.

Feasibility of Upper Cranial Nerve Sonication in Human Application via Neuronavigated Single-Element Pulsed Focused Ultrasound

Sonicating deep brain regions with pulsed focused ultrasound using magnetic resonance imaging-guided neuronavigation single-element piezoelectric transducers is a new area of exploration for neuromodulation. Upper cranial nerves such as the trigeminal nerve and other nerves responsible for sensory/motor functions in the head may be potential targets for ultrasound pain therapy. The location of upper cranial nerves close to the skull base poses additional challenges when compared with conventional cortical or middle brain targets. In the work described here, a series of computational and empirical testing methods using human skull specimens were conducted to assess the feasibility of sonicating the trigeminal pathway near the sphenoid bone region. The results indicate a transducer with a focal length of 120 mm and diameter of 85 mm (350 kHz) can deliver sonication to upper cranial nerve regions with spatial accuracy comparable to that of focused ultrasound brain targets used in previous human studies. Temperature measurements in cortical bone and in the skull base with embedded thermocouples yield evidence of minimal bone heating. Conventional pulse parameters were found to cause reverberation interference patterns near the cranial floor; therefore, changes in pulse cycles and pulse repetition frequency were examined for reducing standing waves. Limitations and considerations for conducting ultradeep focal targeting in human applications are discussed.

Pain Relief in a Trigeminal Neuralgia Model via Optogenetic Inhibition on Trigeminal Ganglion Itself With Flexible Optic Fiber Cannula

The trigeminal ganglion (TG) is the primary site of aberration in trigeminal neuralgia (TN), and hence a crucial site where afferent input can be modulated. Here, we postulated that inhibiting TG via optogenetics using flexible optic cannula would diminish brainstem trigeminal nucleus caudalis (TNC) neuronal activity and pain behavior in TN rat model. Infraorbital nerve constriction was employed to induce TN in female Sprague-Dawley rats, while naive and sham rats served as controls. TG-directed microinjections of AAV virus containing either the optogenetic or null vector were delivered to rats in each group. In vivo electrophysiological responses were obtained from the ventral posteromedial nucleus (VPm) of the thalamus with simultaneous TG optogenetic stimulation using flexible optic cannula as well the effects on behavioral responses were investigated. Recordings in TN rats revealed a decrease in burst firing activity during yellow laser driven inhibition on TG, as well as considerably improved behavioral responses. In contrast, we noticed persistent hypersensitivity and increased tonic firing with blue laser stimulation which indicates that TG inhibition can synchronize trigeminal pain signal transmission in a TN animal model. The potential of an optogenetic approach in TG itself with flexible optic fiber to directly disrupt the trigeminal pain circuitry delivers fundamental underpinnings toward its prospective as a trigeminal neuralgia management.

Peripheral Neuromodulation for the Management of Headache

Context

Neuromodulation is an expanding field of study for headache treatment to reduce pain by targeting structures within the nervous system that are commonly involved in headache pathophysiology, such as the vagus nerve (VNS), occipital nerves, or sphenopalatine ganglion (SPG) for stimulation. Pharmaceutical medical therapies for abortive and prophylactic treatment, such as triptans, NSAIDs, beta-blockers, TCAs, and antiepileptics, are effective for some individuals, but the role that technology plays in investigating other therapeutic modalities is essential. Peripheral neuromodulation has gained popularity and FDA approval for use in treating certain headaches and migraine headache conditions, particularly in those who are refractory to treatment. Early trials found FDA approved neurostimulatory implant devices, including Cephaly and SpringTMS, improved patient-oriented outcomes with reductions in headaches per month (frequency) and severity.

Evidence Acquisition

This was a narrative review. The sources for this review are as follows: Searching on PubMed, Google Scholar, Medline, and ScienceDirect from 1990 - 2019 using keywords: Peripheral Neuromodulation, Headache, vagus nerve, occipital nerves, sphenopalatine ganglion.

Results

The first noninvasive neurostimulator device approved for migraine treatment was the Cefaly device, an external trigeminal nerve stimulation device (e-TNS) that transcutaneously excites the supratrochlear and supraorbital branches of the ophthalmic nerve. The second noninvasive neurostimulation device receiving FDA approval was the single-pulse transcranial magnetic stimulator, SpringTMS, positioned at the occiput to treat migraine with aura. GammaCore is a handheld transcutaneous vagal nerve stimulator applied directly to the neck at home by the patient for treatment of cluster headache (CH) and migraine. Several other devices are in development for the treatment of headaches and target headache evolution at different levels and inputs. The Scion device is a caloric vestibular stimulator (CVS) which interfaces with the user through a set of small cones resting in the ear canal on either side and held in place by modified over-ear headphones. The pulsante SPG Microstimulator is a patient-controlled device implanted in the patient’s upper jaw via an hour-long oral procedure to target the sphenopalatine ganglion. The occipital nerve stimulator (ONS) is an invasive neuromodulation device for headache treatment that consists of an implanted pulse generator on the chest wall connected to a subcutaneous lead with 4 - 8 electrodes that is tunneled the occiput.

Conclusions

The aim of this review is to provide a comprehensive overview of the efficacy, preliminary outcomes, and limitations of neurostimulatory implants available for use in the US and those pending further development.

Repetitive percutaneous radiofrequency thermocoagulation for persistent idiopathic facial pain and central neuropathic pain attributed to multiple sclerosis-a retrospective monocentric analysis

BACKGROUND

Persistent idiopathic facial pain (PIFP) is a debilitating chronic pain condition with pain radiating to trigeminal dermatomes. Typically, there are no pathological findings that can be identified during workup and therapy is symptomatic. Facial pain is common in patients with multiple sclerosis (central neuropathic pain attributed to MS). Our aim was to evaluate the effectiveness of percutaneous radiofrequency thermocoagulation (PRTC) of the gasserian ganglion and the duration of pain relief, as well as the identification of factors associated with its outcome.

METHODS

Data on all the above-mentioned patients that have been treated with PRTC between 2009 and 2019 were included into the study. The outcome was assessed with a six-tiered score from 1 (complete remission) to 6 (no benefit). Univariate and multivariate analyses were performed in order to obtain factors associated with the outcome.

RESULTS

A total of 52 patients were included. The total number of procedures performed was 114. 61.5% of patients who experienced temporary pain relief that lasted for a median of 60 days (range 3-1490 days). In patients with recurrence, the fraction of successful interventions was higher, and also transient, with successful pain amelioration in over 80% of patients. Successful responses to PRTC were observed in 27.9% after 1 year, 19.4% after 2 years, and 8.3% after 3 years. The only independent variable predicting pain relief was a repeat intervention with a history of ≥ 2 interventions (OR: 4.36, 95%-CI: 1.34-14.34, p = 0.015). No severe complications occurred.

CONCLUSIONS

Our data showed good and immediate pain relief after PRTC in the majority of our patients. PRTC is a low-risk procedure that can be discussed as an option in case of failure of medical treatment even in critically ill patients and can be repeated with good results when necessary. Long-term pain amelioration, even with repeated procedures, was not possible and no patient was permanently cured.

Neuromodulation in headache and craniofacial neuralgia: guidelines from the Spanish Society of Neurology and the Spanish Society of Neurosurgery

INTRODUCTION

Numerous invasive and non-invasive neuromodulation devices have been developed and applied to patients with headache and neuralgia in recent years. However, no updated review addresses their safety and efficacy, and no healthcare institution has issued specific recommendations on their use for these 2 conditions.

METHODS

Neurologists from the Spanish Society of Neurology's (SEN) Headache Study Group and neurosurgeons specialising in functional neurosurgery, selected by the Spanish Society of Neurosurgery (SENEC), performed a comprehensive review of articles on the MEDLINE database addressing the use of the technique in patients with headache and neuralgia.

RESULTS

We present an updated review and establish the first set of consensus recommendations of the SEN and SENC on the use of neuromodulation to treat headache and neuralgia, analysing the current levels of evidence on its effectiveness for each specific condition.

CONCLUSIONS

Current evidence supports the indication of neuromodulation techniques for patients with refractory headache and neuralgia (especially migraine, cluster headache, and trigeminal neuralgia) selected by neurologists and headache specialists, after pharmacological treatment options are exhausted. Furthermore, we recommend that invasive neuromodulation be debated by multidisciplinary committees, and that the procedure be performed by teams of neurosurgeons specialising in functional neurosurgery, with acceptable rates of morbidity and mortality.

Persistent Idiopathic Facial Pain Originating from Cervical Abnormalities

BACKGROUND

Persistent idiopathic facial pain is characterized by persistent facial or oral pain in the absence of a neurologic deficit. This underexplored pain may be conducted by various nerves, including cranial nerves and upper cervical spinal roots, and its etiology is unclear.

CASE DESCRIPTION

A patient presented with persistent idiopathic facial pain associated with occipital muscle stiffness after an improper neck massage. The patient achieved almost complete pain relief by coblation of right upper cervical nerves (C1 and C2 spinal roots) followed by continuous cervical epidural analgesia for a period of 3 weeks. The analgesic effect was stable during the 3-month follow-up period.

CONCLUSIONS

Persistent idiopathic facial pain may be cervicogenic, and treatments focusing on cervical spinal roots may provide satisfactory pain control in patients with cervical abnormalities.

Sphenopalatine ganglion: block, radiofrequency ablation and neurostimulation - a systematic review

Background

Sphenopalatine ganglion is the largest collection of neurons in the calvarium outside of the brain. Over the past century, it has been a target for interventional treatment of head and facial pain due to its ease of access. Block, radiofrequency ablation, and neurostimulation have all been applied to treat a myriad of painful syndromes. Despite the routine use of these interventions, the literature supporting their use has not been systematically summarized. This systematic review aims to collect and summarize the level of evidence supporting the use of sphenopalatine ganglion block, radiofrequency ablation and neurostimulation.

Methods

Medline, Google Scholar, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases were reviewed for studies on sphenopalatine ganglion block, radiofrequency ablation and neurostimulation. Studies included in this review were compiled and analyzed for their treated medical conditions, study design, outcomes and procedural details. Studies were graded using Oxford Center for Evidence-Based Medicine for level of evidence. Based on the level of evidence, grades of recommendations are provided for each intervention and its associated medical conditions.

Results

Eighty-three publications were included in this review, of which 60 were studies on sphenopalatine ganglion block, 15 were on radiofrequency ablation, and 8 were on neurostimulation. Of all the studies, 23 have evidence level above case series. Of the 23 studies, 19 were on sphenopalatine ganglion block, 1 study on radiofrequency ablation, and 3 studies on neurostimulation. The rest of the available literature was case reports and case series. The strongest evidence lies in using sphenopalatine ganglion block, radiofrequency ablation and neurostimulation for cluster headache. Sphenopalatine ganglion block also has evidence in treating trigeminal neuralgia, migraines, reducing the needs of analgesics after endoscopic sinus surgery and reducing pain associated with nasal packing removal after nasal operations.

Conclusions

Overall, sphenopalatine ganglion is a promising target for treating cluster headache using blocks, radiofrequency ablation and neurostimulation. Sphenopalatine ganglion block also has some evidence supporting its use in a few other conditions. However, most of the controlled studies were small and without replications. Further controlled studies are warranted to replicate and expand on these previous findings.

Electronic supplementary material

The online version of this article (10.1186/s10194-017-0826-y) contains supplementary material, which is available to authorized users.