Chronic Headache: a Review of Interventional Treatment Strategies in Headache Management. Curr Pain Headache Rep. 2019;23:68. [PMID: 31359257 DOI: 10.1007/s11916-019-0806-9]

Sequential administration of peripheral nerve blocks and onabotulinumtoxinA for the treatment of chronic migraine and other headache disorders-A retrospective tolerability and safety study

OBJECTIVE

To determine the tolerability and safety of concurrent peripheral nerve blocks and onabotulinumtoxinA treatment during a single outpatient clinic procedure visit.

BACKGROUND

Procedural interventions are available for the treatment of headache disorders. OnabotulinumtoxinA and peripheral nerve blocks are used as alternatives or in addition to oral therapies to reduce the frequency and intensity of migraine attacks. There is currently a lack of safety data focusing on the sequential administration of local anesthetic via peripheral nerve blocks and onabotulinumtoxinA during a single clinical encounter for the treatment of headache. The primary aim of the study was to determine the safety and tolerability of concurrent peripheral nerve blockade and onabotulinumtoxinA injections during a single outpatient clinic procedure visit. We hypothesized that the dual intervention would be safe and well tolerated by patients with chronic migraine and other headache disorders.

METHODS

A retrospective chart review was performed using clinical data from patients seen by multiple providers over a 16-month timeframe at one outpatient headache clinic. Patients were identified by procedure codes and those receiving peripheral nerve block(s) and onabotulinumtoxinA injections during a single encounter within the study period were eligible for inclusion. Inclusion criteria were (1) patients 18 years and older who were (2) receiving both peripheral nerve blocks and onabotulinumtoxinA injections for the treatment of chronic migraine. Patients were excluded if they were under age 18, received their procedure outside of the clinic (emergency room, inpatient ward), or were receiving sphenopalatine ganglion blocks. Age- and sex-matched patients who received one procedure, either peripheral nerve blocks or onabotulinumtoxinA, were used for control. The primary outcome of this safety study was the number of adverse events that occurred in the dual intervention group compared to the single intervention control arms. Information regarding adverse events was gathered via retrospective chart review. If an adverse event was recorded, it was then graded by the reviewer utilizing the Common Terminology Criteria for Adverse Events ranging from Grade 1 Mild Event to Grade 5 Death. Additionally, it was noted whether the adverse event led to treatment discontinuation.

RESULTS

In total, 375 patients were considered eligible for inclusion in the study. After age and sex matching of controls, 131 patients receiving dual intervention were able to be compared to 131 patients receiving onabotulinumtoxinA alone and 104 patients receiving dual intervention were able to be compared to 104 patients receiving peripheral nerve block(s) alone. The primary endpoint analysis showed no significant difference in total adverse events between dual intervention compared to nerve blocks alone or onabotulinumtoxinA alone. The number of adverse events that led to treatment discontinuation approached but did not reach statistical significance for those receiving dual intervention versus onabotulinumtoxinA alone in the number of adverse events that led to treatment termination (4.6%, 6/131 vs. 0.8%, 1/131, p = 0.065); however, the number of patients who discontinued therapy was not significantly different between those groups (2.3%, 3/131 vs. 0.8%, 1/131; p = 0.314; odds ratio 0.3 [0-3.2]; p = 0.338).

CONCLUSIONS

In this retrospective chart review, there was no significant difference in adverse events or therapy discontinuation between patients receiving sequential peripheral nerve block(s) and onabotulinumtoxinA injections versus those receiving either peripheral nerve block(s) or onabotulinumtoxinA injections alone. As a result, we concluded that the combination procedure is likely safe and well tolerated in routine clinical practice.

Role of peripheral nerve stimulation in treating chronic neuropathic pain: an international focused survey of pain medicine experts

Interventional pain management (IPM) options for refractory neuropathic pain (NP) have recently increased with availability of peripheral nerve stimulation (PNS) equipment and expertise. Given a lack of high-quality evidence and guidelines on this topic, we sought to understand the perception of physicians with expertise in treating NP regarding IPM and the role of PNS. We emailed a survey in March 2022 to international NP experts including pain medicine physicians, researchers, and leaders of 11 professional pain societies. No representatives from vendors of PNS systems were included in the design of the survey nor as respondents. Among 24 respondents (67% of those contacted), the distal common peroneal, tibial, and sural nerves were most frequently targeted (60%) with PNS. Persistent postsurgical pain of more than 3 months was the most common indication for PNS (84%). The aggregate NP treatment algorithm in order of median rank was non-opioid medications as first line, IPM including epidural/perineural steroid injections tied with transcutaneous electrical nerve stimulation as second line, pulsed radiofrequency (RF) tied with RF ablation/denervation as third line, temporary then permanent PNS as fourth line, followed by spinal cord stimulation, opioids, cryoablation, botulinum, peripheral nerve field stimulation, intrathecal targeted drug delivery, and others. Before offering PNS, 12 respondents (50%) indicated their preference for trialing non-neuromodulation treatments for 1-3 months. Twenty-two respondents (92%) agreed PNS should be offered early in the treatment of neuropathic pain. The most common barriers to PNS use were cost, lack of high-quality evidence in support of its use, lack of exposure to PNS in training programs, and lack of familiarity with the use of ultrasound guidance. PNS appears to have an increasing role in the treatment of NP but more research is needed on the outcomes of PNS to elucidate its role.

Safety and Efficacy of Radiofrequency Ablation and Epidural Steroid Injection for Management of Cervicogenic Headaches and Neck Pain: Meta-Analysis and Literature Review

Dysfunction of the cervical spine and its anatomical features, mostly innervated by the C1, C2, and C3 spinal nerves, can result in a secondary headache known as cervicogenic headache (CHA), mainly characterized by unilateral pain. The usefulness of pharmaceutical medications and physical therapy is currently the subject of scant literature. Interventional pain management techniques can be applied when conservative treatment is unsuccessful. This study looks at radiofrequency ablation (RFA) and epidural steroid injection (ESI) to identify their safety and efficacy in managing patients with cervicogenic headaches and neck pain. Three databases - PubMed, Cochrane CENTRAL Library, and Embase were searched, and 110 studies were identified. Nine screening processes were included for review and meta-analysis. Statistical evaluation was conducted through STATA version 17 (College Station, TX: StataCorp LLC) and effect measures were reported through random effects model risk ratios. The main subject of focus included three following outcomes: incidences of pain relief, degree and duration of pain, and incidences of adverse effects. The findings showed both interventions relieved pain by a factor of >50%, demonstrating a relative effects risk ratio of 1.45 (-0.50, 3.39) for RFA: pain relief, 84.76 (82.82, 86.69) RFA: adverse effects, and 19.46 (18.80, 20.11) ESI: pain relief at 95% confidence interval. The efficacy of RFA and ESI differ. Both interventions are effective in the reduction of cervicogenic headache pain intensity. However, their complication rates and pain duration are considerably different. With ESI, the headaches can still recur weekly, demanding the use of oral analgesics to deal with them. On the other hand, RFA has a low complication rate. Improving guidance from imaging technologies, RFA has the potential to be the most effective interventional treatment.

Considerations in Permanent Implantation of Peripheral Nerve Stimulation (PNS) for Chronic Neuropathic Pain: An International Cross Sectional Survey of Implanters

INTRODUCTION

Novel minimally invasive short-term and long-term peripheral nerve stimulation (PNS) systems have revolutionized targeted treatment of chronic neuropathic pain. We present an international survey of PNS-implanting pain physicians to assess what factors they consider when offering permanent PNS.

METHODS

This cross-sectional study consisted of a survey (Qualtrics) that was distributed to PNS-implanting physicians in a device supplier's entire email database on November 13, 2020, with 3 weeks of response time. Physicians' contact information in the form of their email addresses had been previously collected by the supplier upon device distribution with permission to use survey responses for research.

RESULTS

Of 2,032 database physicians, 40 physicians representing 37 institutions responded to the survey. The most common application of PNS was mononeuropathic pain (57%). The most frequently targeted nerve was the suprascapular nerve (29%). 14% of physicians reported 81-100% of their implants were dual-lead. The representative physicians ranged broadly in their most frequently-targeted nerves. Although mononeuropathic pain was the most common indication for PNS, there was still varied response regarding other indications such as CRPS and post-surgical chronic pain.

CONCLUSION

In context of a low response rate, identifying such factors can help update the prevailing treatment algorithm for interventional therapies, assist pain physicians in better identifying which patients are the best candidates for PNS, and inform future clinical trial design on PNS efficacy.

Peripheral Nerve Stimulation for Treatment of Headaches: An Evidence-Based Review

Headaches are one of the most common medical complaints worldwide, and treatment is often made difficult because of misclassification. Peripheral nerve stimulation has emerged as a novel treatment for the treatment of intractable headaches in recent years. While high-quality evidence does exist regarding its use, efficacy is generally limited to specific nerves and headache types. While much research remains to bring this technology to the mainstream, clinicians are increasingly able to provide safe yet efficacious pain control.

Experimental evidence of a functional relationship within the brainstem trigeminocervical complex in humans

ABSTRACT

The existence of a trigeminocervical complex (TCC) has been suggested based on animal data, but only indirect evidence exists in humans. We investigated the functional relationship between the trigeminal and the occipital region by stimulating one region and measuring electrical pain thresholds (EPTs) of the corresponding opposite region. This study consists of two single-blinded, randomized protocols. 40 healthy participants were recruited in the propaedeutic Protocol I. EPTs were measured on the V1 and the greater occipital nerve (GON) dermatome bilaterally as well as on the left forearm longitudinally before and after application of topical capsaicin. Protocol II was then online pre-registered and, additionally, the ipsilateral trigeminal dermatomes V2 and V3 were tested. GON stimulation increased the EPT ipsilateral at V1 after 20 minutes (p=0.006) compared to baseline, whereas trigeminal stimulation increased the EPT at the ipsilateral (p=0.023) as well as the contralateral GON (p=0.001) following capsaicin application. Protocol II confirmed these results and additionally showed that GON stimulation with capsaicin increased EPTs ipsilateral at all three trigeminal dermatomes and that trigeminal stimulation on V1 led to an ipsilateral increase of EPTs at GON, V2 and V3. Our data suggest a strong functional interplay between the trigeminal and occipital system in humans. The fact that stimulation of one of these dermatomes increases the electrical pain threshold of the respective other nerve could be explained by segmental inhibition on brainstem level.

The Impact of Surgery-Related Muscle Injury on Prevalence and Characteristics of Acute Postcraniotomy Headache - A Prospective Consecutive Case Series

BACKGROUND AND OBJECTIVE

 The latest third edition of the International Classification of Headache Disorders delineates diagnostic criteria for acute headache attributed to craniotomy (AHAC), but data on possible predisposing factors are sparse. This prospective observational study aims to evaluate the impact of surgery-related muscle incision on the prevalence, severity, and characteristics of AHAC.

PATIENTS AND METHODS

 Sixty-four consecutive adults (mean age: 54.2 ± 15.2 years; 26 males and 38 females) undergoing cranial neurosurgery for various reasons without preoperative headache were included. After regaining consciousness, all patients reported their average daily headache on a numeric pain rating scale (NRS; range: 0-10), headache characteristics, as well as analgesic consumption from day 1 to 3 after surgery. Three distinct patient cohorts were built with respect to the surgical approach (craniotomy ± muscle incision; burr hole surgery) and group comparisons were performed. Additionally, patients with AHAC ≥ 3 NRS were reevaluated at 7.2 ± 2.3 months following treatment by means of standardized questionnaires to determine the prevalence of persistent headache attributed to craniotomy as well as headache-related disability and quality of life.

RESULTS

 Thirty of 64 (46.9%) patients developed moderate to severe AHAC (NRS ≥ 3) after cranial neurosurgery. There were no significant group differences with regard to age, gender, or general health condition (American Society of Anesthesiologists Physical Status Classification). Craniotomy patients with muscle incision suffered from significantly higher early postoperative mean NRS scores compared with their counterparts without procedure-related muscle injury (3.4 ± 2.3 vs. 2.3 ± 1.9) as well as patients undergoing burr hole surgery (1.2 ± 1.4; p = 0.02). Moreover, the consumption of nonopioid analgesics was almost doubled following muscle-transecting surgery as compared with muscle-preserving procedures (p = 0.03). Young patient age (odds ratio/95% confidence interval for each additional year: 0.93/0.88-0.97) and surgery-related muscle injury (5.23/1.62-19.41) were identified as major risk factors for the development of AHAC ≥ 3 NRS. There was a nonsignificant trend toward higher pain chronification rate as well as headache-related disability after craniotomy with muscle injury.

CONCLUSION

 Surgery-related muscle damage may be an important predisposing factor for AHAC. Therefore, if a transmuscular approach is unavoidable, the neurosurgeon should be aware of the need for adequately adjusted intra- and postoperative analgesia in these cases.

Expert panel’s guideline on cervicogenic headache: The Chinese Association for the Study of Pain recommendation

Cervicogenic headache (CEH) has been recognized as a unique category of headache that can be difficult to diagnose and treat. In China, CEH patients are managed by many different specialties, and the treatment plans remain controversial. Therefore, there is a great need for comprehensive evidence-based Chinese experts’ recommendations for the management of CEH. The Chinese Association for the Study of Pain asked an expert panel to develop recommendations for a series of questions that are essential for daily clinical management of patients with CEH. A group of multidisciplinary Chinese Association for the Study of Pain experts identified the clinically relevant topics in CEH. A systematic review of the literature was performed, and evidence supporting the benefits and harms for the management of CEH was summarized. Twenty-four recommendations were finally developed through expert consensus voting for evidence quality and recommendation strength. We hope this guideline provides direction for clinicians and patients making treatment decisions for the management of CEH.