Accuracy of augmented reality-guided needle placement for pulsed radiofrequency treatment of pudendal neuralgia: a pilot study on a phantom model.

Background: Pudendal neuralgia (PN) is a chronic neuropathy that causes pain, numbness, and dysfunction in the pelvic region. The current state-of-the-art treatment is pulsed radiofrequency (PRF) in which a needle is supposed to be placed close to the pudendal nerve for neuromodulation. Given the effective range of PRF of 5 mm, the accuracy of needle placement is important. This study aimed to investigate the potential of augmented reality guidance for improving the accuracy of needle placement in pulsed radiofrequency treatment for pudendal neuralgia. Methods: In this pilot study, eight subjects performed needle placements onto an in-house developed phantom model of the pelvis using AR guidance. AR guidance is provided using an in-house developed application on the HoloLens 2. The accuracy of needle placement was calculated based on the virtual 3D models of the needle and targeted phantom nerve, derived from CBCT scans. Results: The median Euclidean distance between the tip of the needle and the target is found to be 4.37 (IQR 5.16) mm, the median lateral distance is 3.25 (IQR 4.62) mm and the median depth distance is 1.94 (IQR 7.07) mm. Conclusion: In this study, the first method is described in which the accuracy of patient-specific needle placement using AR guidance is determined. This method could potentially improve the accuracy of PRF needle placement for pudendal neuralgia, resulting in improved treatment outcomes.

Comparison of tibial nerve pulsed radiofrequency and intralesional radiofrequency thermocoagulation in the treatment of painful calcaneal spur and plantar fasciitis: A randomized clinical trial.

OBJECTIVE: Ultrasound-guided tibial nerve pulsed radiofrequency (US-TN PRF) and fluoroscopy-guided intralesional radiofrequency thermocoagulation (FL-RFT) adjacent to the painful calcaneal spur are two interventions for pain management in painful calcaneal spur (PCS) and plantar fasciitis (PF). This study aimed to compare the effectiveness of the two procedures. DESIGN: A prospective, randomized, single-blind study. SETTING: Single-center pain clinic. SUBJECTS: Forty-nine patients who met the inclusion criteria were randomized into two groups. METHODS: 25 patients (group U) received US-TN PRF at 42 °C for 240 s, while 24 patients (group F) received intralesional FL-RFT at 80 °C for 90 s. The most severe Numeric Rating Scale (NRS) score during the first morning steps and the American Orthopedic Foot and Ankle Society (AOFAS) ankle hindfoot scores were used to evaluate the effectiveness of the procedures. The study's primary outcome assessed treatment effectiveness using the NRS, whereas the secondary outcomes included changes in the AOFAS score and the incidence of procedure-related mild adverse events. RESULTS: NRS and AOFAS scores significantly improved in groups U and F at 1 and 3 months compared to baseline (p < 0.05), and there was no significant difference between the groups. At month 1, 50% or greater pain relief was achieved in 72% of patients in group U and 75% in group F. No significant difference was observed in the incidence of mild adverse events between the groups. CONCLUSIONS: US-TN PRF and intralesional FL-RFT have shown significant effectiveness in the treatment of PCS and PF. Larger randomized controlled trials are needed.

Radiofrequency for chronic lumbosacral and cervical pain: Results of a consensus study using the RAND/UCLA appropriateness method.

BACKGROUND: Despite the routine use of radiofrequency (RF) for the treatment of chronic pain in the lumbosacral and cervical region, there remains uncertainty on the most appropriate patient selection criteria. This study aimed to develop appropriateness criteria for RF in relation to relevant patient characteristics, considering RF ablation (RFA) for the treatment of chronic axial pain and pulsed RF (PRF) for the treatment of chronic radicular pain. METHODS: The RAND/UCLA Appropriateness Method (RUAM) was used to explore the opinions of a multidisciplinary European panel on the appropriateness of RFA and PRF for a variety of clinical scenarios. Depending on the type of pain (axial or radicular), the expert panel rated the appropriateness of RFA and PRF for a total of 219 clinical scenarios. RESULTS: For axial pain in the lumbosacral or cervical region, appropriateness of RFA was determined by the dominant pain trigger and location of tenderness on palpation with higher appropriateness scores if these variables were suggestive of the diagnosis of facet or sacroiliac joint pain. Although the opinions on the appropriateness of PRF for lumbosacral and cervical radicular pain were fairly dispersed, there was agreement that PRF is an appropriate option for well-selected patients with radicular pain due to herniated disc or foraminal stenosis, particularly in the absence of motor deficits. The panel outcomes were embedded in an educational e-health tool that also covers the psychosocial aspects of chronic pain, providing integrated recommendations on the appropriate use of (P)RF interventions for the treatment of chronic axial and radicular pain in the lumbosacral and cervical region. CONCLUSIONS: A multidisciplinary European expert panel established patient-specific recommendations that may support the (pre)selection of patients with chronic axial and radicular pain in the lumbosacral and cervical region for either RFA or PRF (accessible via https://rftool.org). Future studies should validate these recommendations by determining their predictive value for the outcomes of (P)RF interventions.

Comparative evaluation of functional outcome and pain relief after pulsed radiofrequency of the saphenous nerve within and distal to the adductor canal in medial compartment knee osteoarthritis: A randomized double-blind trial.

Background and Aims: Pulsed radiofrequency (PRF) of the saphenous nerve (SN) has shown effective pain relief in knee pain because of knee osteoarthritis (KOA). The adductor canal (AC) contains other sensory nerves innervating the medial part of the knee joint apart from SN. We compared the PRF of SN within and outside the AC for their quality and duration of pain relief in knee osteoarthritis of the medial compartment (KOA-MC). Material and Methods: We conducted a randomized prospective study in 60 patients with anteromedial knee pain because of KOA-MC. Patients in group A received PRF-SN, and those in group B received PRF-AC. The primary objectives were comparison of pain by Visual Analog Scale (VAS) scores and changes in quality of daily living by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and OXFORD knee scores. The secondary objectives were comparison of analgesic requirements using Medicine Quantification Scale (MQS) scores and block-related complications. Intra-group comparison was performed by analysis of variance. Inter-group normally distributed data were assessed by Student's t-test, non-normally distributed and ordinal data were assessed by Mann-Whitney U-test, and categorical data were assessed by Chi-square test. A P value of <0.05 was considered significant. Results: VAS scores were significantly lower in Gr-B at 12 weeks. The WOMAC scores and OXFORD scores at 4, 8, 12, and 24 weeks were significantly lower in Gr-B compared to Gr-A. Conclusion: The PRF-AC provides better pain relief and functional outcome than PRF-SN; however, duration of pain relief was not significantly different.

Efficacy and Safety of High-Voltage Pulsed Radiofrequency versus Standard-Voltage Pulsed Radiofrequency for Patients with Neuropathic Pain: A Literature Review and Meta-Analysis.

Background: Neuropathic pain (NP) is recognized as one of the most difficult pain syndromes which lacks a safe, well-tolerated and effective treatment. Pulsed radiofrequency (PRF), a novel and minimally invasive interventions, has been introduced to alleviate various types of NP. Previous studies reported PRF with higher voltage could further improve the treatment efficacy. Therefore, we conducted this systematic review and meta-analysis to determine whether high-voltage PRF is superior to standard-voltage PRF for the treatment of NP patients. Methods: Databases published from the date of inception until 15 March 2022 on PubMed/MEDLINE, EMBASE, Web of Science and the Cochrane Library were searched for RCTs comparing high-voltage PRF and standard-voltage PRF in NP patients. The primary outcome measures were the efficiency rates of NP patients with high-voltage PRF or standard-voltage PRF treatment. Data analysis was conducted using the Review Manager software (RevMan V.5.3). Results: Six RCTs involving 423 patients were included in our meta-analysis. Compared with standard-voltage PRF group, the high-voltage PRF group attained a higher efficiency rate at 1 month (P = 0.04; I2 = 0%), 3 months (P = 0.04; I2 = 0%), 6 months (P = 0.002; I2 = 0%) post-procedure respectively. There was no significant difference in the complications between the two groups. Conclusion: Our study supported that high-voltage PRF attained more satisfactory efficacy than standard-voltage PRF without increased side effects. High-voltage PRF could be a promising, effective, minimally invasive technology for NP patients.

Pulsed Radiofrequency for Auriculotemporal Neuralgia: A Case Report.

Auriculotemporal neuralgia is a rare facial pain disorder with no therapeutic evidence for refractory cases. We described a male patient with right auriculotemporal neuralgia, refractory to anesthetic nerve blocks and botulinum toxin type A injections, who was successfully treated with pulsed radiofrequency without adverse events. Pulsed radiofrequency may be an effective and safe treatment for refractory auriculotemporal neuralgia.

Pulsed radiofrequency on peripheral nerve as a rehabilitation aid.

The work described below explores the field of the effects of pulsed radiofrequency for pain relief purposes. While the effects of this technique on pain modulation (A-delta and C fibers) are relatively well-known, little has been written yet about the potential of pulsed radiofrequency interactions with other fibers. The proposed algorithm, specifically elaborated, investigates the effect of this technique on neuromuscular fatigue, through a surface electromyographic study of the femoral nerve of a patient with residual pain after knee arthroplasty surgery, before and after the treatment. This work yields a preliminary result that is encouraging for subsequent large-scale studies.

Pulsed Radiofrequency Therapy at Different Voltages on Dorsal Root Ganglia Using Multifunctional Catheter to Treat Low Back Pain: A Comparative Retrospective Study.

BACKGROUND: Applying pulsed radiofrequency (PRF) to the dorsal root ganglion (DRG) is an electrical neuromodulation technique, a valid complementary therapeutic treatment for failed back surgery syndrome (FBBS). Peridurolysis, when applied to vertebral canal adhesions, can be performed with dedicated catheters, providing patients with the benefits of mechanical, electrical, and pharmacological techniques. OBJECTIVES: The aim of this study was to evaluate PRF's effects on the DRG as part of FBSS treatment at different follow-up times, comparing 2 groups of patients exposed to distinct levels of voltage (100 V vs. 45 V) from a PRF generator. STUDY DESIGN: A retrospective observational study was performed. SETTING: The study was conducted on a sample of patients from an Italian hospital. METHODS: PRF's effects on the DRG as part of FBSS treatment were evaluated through the Numeric Rating Scale (NRS) and the monitoring of 155 patients' opioid consumption at 3, 6, and 9 months. A Cosman® G4 model PRF generator was used. During follow-up periods, the Friedman test was applied to detect differences in outcomes between the 2 groups of patients, who were treated with different levels of voltage. RESULTS: The most frequent diagnosis (61.29%) was FBBS in patients at a mean age of 64 (± 11.8) years old. All patients were treated with PRF on the dorsal ganglion, with the addition of a drug mixture. Most were treated with 100 V (62%). A statistically significant decrease (P < 0.001) in the NRS score emerged both as a whole and in the 2 distinct groups. Moreover, the group of 100 V patients showed a significant (P = 0.0360) reduction in the use of opioids. LIMITATIONS: This observational retrospective study was based on a convenience sampling that involved a limited number of patients. CONCLUSIONS: E-field technology is the only way to generate a constant 38°/42° PRF and 100 V level throughout surgical interventions (respecting the exposure times "set" by the operator). The patient will not feel any pain or electric current because the generated milliamperes will be greatly reduced.

Pulsed Radiofrequency of the Auriculotemporal Nerve to Reduce the Intensity of Tinnitus.

INTRODUCTION: Stimulation of the nonauditory nervous systems via the trigeminal nerve pathways can be a promising intervention for patients with tinnitus refractory to medical, conservative, and other treatment options. Therapy of the mandibular division of the trigeminal nerve through the auriculotemporal nerve has been reported as useful for patients with tinnitus. OBJECTIVES: The objective of our study was to study the long-term effects of pulsed radiofrequency of the auriculotemporal nerve in a large group of tinnitus sufferers and to find predictors for a prosperous result. DESIGN: A monocenter backward-looking group study. RESULTS: In a two-year period, 67 tinnitus patients had pulsed radiofrequency of the auriculotemporal nerve. Twentythree (35%) reported reduced tinnitus loudness at the 7-week post-treatment follow-up. These patients valued the improvements as: 61% good, 22% moderate, and 17% slight. In 3% of patients, tinnitus magnified after the treatment. The odds of permanent tinnitus relief after successful pulsed radiofrequency of the auriculotemporal nerve are 68% at 1 year postoperative. In tinnitus patients without cervical pain 62% had an improvement following pulsed radiofrequency of the auriculotemporal nerve compared to 28% in those not fulfilling this criterion (p=0.024). CONCLUSIONS: Neuromodulation of the auriculotemporal nerve is an uncomplicated remedy for tinnitus. In a select group of tinnitus patients this treatment can a good relief of their tinnitus for a long period. Especially, tinnitus sufferers without cervical pain will benefit of this therapy.

Pulsed Radiofrequency Neuromodulation for Post-Stroke Shoulder Pain in Patients with Hemorrhagic Stroke.

Objective: Post-stroke shoulder pain (PSSP) is a common complication that limits the range of motion (ROM) of the shoulder, the patient's rehabilitation and in turn, affects the patients' quality of life (QOL). Several treatment modalities such as sling, positioning, strapping, functional electrical stimulation (FES), and nerve block have been suggested in literatures, however none of the treatments had long-term effects for PSSP. In this study, the authors evaluated clinical efficacy of pulsed radiofrequency (PRF) neuromodulation on the suprascapular nerve for PSSP, and suggested it as a potential treatment with long-term effect. Methods: This retrospective case series was conducted at a single center, a private practice institution. From 2013 to 2021, 13 patients with PSSP underwent PRF neuromodulation of the suprascapular nerve. The primary outcome measure was the visual analog scale (VAS) score. The secondary outcome measurements included the shoulder ROM, disability assessment scale (DAS), modified Ashworth scale (mAS), modified Rankin scale (mRS), and EuroQol-5 dimension-3L questionnaire (EQ-5D-3L) scores. These parameters were evaluated before PRF modulation, immediately after PRF modulation, and every three months until the final follow-up visit. Results: Six men and seven women were enrolled, and all patients were followed-up for a minimum of 12 months. The mean VAS score was 7.07 points before PRF neuromodulation and 2.38 points immediately post-procedure. Shoulder ROM for abduction and flexion, DAS for pain, mRS, and EQ-5D-3L demonstrated marked improvement. No complications were reported. Conclusion: PRF neuromodulation of the suprascapular nerve is an effective modality in patients with PSSP, and has long-term effect of pain relief, improvement of QOL.

Comparison of Selective Nerve Root Pulsed Radiofrequency Vs Paramedian Interlaminar Epidural Steroid Injection for the Treatment of Painful Cervical Radiculopathy.

BACKGROUND: Although there are studies evaluating ultrasound-guided selective nerve root pulsed radiofrequency (ULSD-SNRPRF) and fluoroscopy-guided paramedian cervical interlaminar epidural steroid injection (FL-CIESI) for the treatment of chronic cervical radicular pain, no study has compared the efficacy of these 2 methods. OBJECTIVES: This study aimed to compare the efficacy of these 2 methods, their superiority to each other, and the incidence of adverse events. STUDY DESIGN: A prospective, randomized controlled trial. SETTING: Outpatient department of a single-center pain clinic. METHODS: Sixty patients who did not respond to conservative treatments for lower cervical radicular pain were randomly divided into 2 groups. One group underwent ULSD-SNRPRF (Group U), and the other underwent paramedian FL-CIESI (Group F). Patients were evaluated pretreatment, and 3 and 6 months posttreatment. The Numeric Rating Scale (NRS-11) was used to assess clinical improvement, The Neck Disability Index (NDI) to assess improvement in functional disability, and the Self-Leeds Assessment of Neuropathic Symptoms and Signs Pain Score (S-LANSS) to assess the treatment's effect on neuropathic pain. Clinically significant pain relief was defined as a 50% or more pain reduction in the NRS-11. The posttreatment reduction in medication consumption was assessed using the Medication Quantification Scale Version III (MQS III). We also evaluated whether there was a difference in treatment-related characteristics, such as procedure time and adverse events. RESULTS: The procedure time was significantly longer in Group U. Blood aspiration was observed in 2 patients in Group U and vascular spread in one patient in Group F, with no significant difference. At 3 and 6 months posttreatment, NRS-11 and NDI scores showed a significant decrease compared to the pretreatment scores in both groups; there was no difference between the groups. Both treatments effectively improved neuropathic pain, with no significant difference between the S-LANSS scores. There was no difference in the reduction of medication consumption between the groups. LIMITATIONS: There was no sham or control group, and the follow-up period was limited to 6 months. CONCLUSIONS: Pain relief, functional improvement, and safety were similar between groups. ULSD-SNRPRF and paramedian FL-CIESI are 2 different effective techniques for chronic cervical radicular pain. The choice of method should depend on various factors, such as patient preference, operator experience, and availability of resources. An advantage of ULSD over fluoroscopy is that patients and physicians are not exposed to radiation.

A Novel Ultrasound-Guided "Three in One" Approach Plus Interfascial Plane Blocks for the Treatment of Cervicogenic Headache.

Objective: Cervicogenic headache (CEH) is a condition resulting from upper cervical spine dysfunction and associated structural and soft tissue abnormalities, significantly impacting patients' quality of life. To acquire better therapeutic results, we presented a novel ultrasound-guided "three in one" approach plus interfascial plane (IFP) blocks for the treatment of CEH. This approach allows for the modulation of C2 dorsal root ganglion (DRG), third occipital nerve (TON), and C3 medial branch with one-point puncture. Additionally, it allows for IFP blocks between the upper neck and occipital muscles within the same scanning plane. Patients and Methods: We evaluated patients diagnosed with CEH from July 2021 to December 2022 in our pain clinic. We included those who did not respond to conservative treatment and single occipital nerve block, therefore received nerve block or pulsed radiofrequency (PRF) using the "Three in One" approach plus IFP blocks. The accuracy of the ultrasound-guided C2 DRG puncture procedures was confirmed through fluoroscopy with C-arm and the sensory testing of PRF. The therapeutic effect of these interventions was assessed using the numerical rating scale (NRS) scores during telephone follow-ups at 1, 3, and 6 months. Results: Utilizing the "Three in One" approach, a total of 5 patients diagnosed with CEH underwent nerve block plus IFP blocks, while 2 patients underwent PRF plus IFP blocks. Employing ultrasound-guided C2 DRG puncture procedures, the needle tip's correct placement was confirmed through both fluoroscopy and sensory testing of PRF. Notably, none of the cases experienced any complications associated with the approach. Subsequent follow-up assessments revealed an improvement in the NRS scores for CEH in all patients. Conclusion: The ultrasound-guided "Three in One" approach plus IFP blocks may be a potential effective method for the treatment of CEH.

Feasibility of a promising pulsed electrostimulator for rapid motor recovery of foot drop.

Purpose: Foot drop still occurs in clinical practice, including in our case. Treatments for foot drop vary based on its etiology and severity of symptoms. Hence, in intractable foot drop cases, an invasive surgical intervention is needed. Here, we introduce a special noninvasive technique to treat our patient's foot drop. In this approach, we applied STIMPOD NMS460 neuromuscular stimulator device (STIMPOD NMS460), which is a low-frequency (10 Hz or less) transcutaneous electrical nerve stimulation (TENS) device with a pulsed radiofrequency (PRF) component. We are eager to know how effective the device is in treating foot drop, and we compared it with two kinds of surgical interventions. Materials and methods: The device settings are 5 Hz in frequency and 30mA in current amplitude. The device was applied on her left side at the L4 and L5 regions and at the fibular head. Each therapy session consists of individual 15-min treatments on these two body areas, and it only takes a total of 30 minutes. We recorded the change in ankle dorsiflexion degrees and muscle strength of our patient. Results and Conclusions: To our surprise, our patient's actual treatment status through STIMPOD NMS460 showed more effective recovery and no specific side effects than surgical interventions in similar conditions. Besides, after a three-month intervention, her affected ankle dorsiflexion recovered to almost her usual status. The reason why this device has such an effect may be that it has the benefits of TENS and PRF. Besides, some studies have revealed the nerve-repair effect of TENS and PRF. In conclusion, we believe that this device is fairly promising and may be qualified to be used in other patients with foot drop.

Spinal Cord Stimulation in Refractory Postherpetic Neuralgia in Portugal: A Case Report.

Postherpetic neuralgia is one of the most severe complications after herpes zoster infection. Patients who experience persistent pain despite conservative treatment may benefit from interventional therapies, such as spinal cord stimulation. We present the case of a patient with severe refractory postherpetic neuralgia in the right T8 to L1 distribution who responded effectively to spinal cord stimulation. After its implantation, the patient had improvements in pain intensity, pain-related interference, quality of life, and satisfaction, with a simultaneous reduction of previous medications. This case report highlights the role of spinal cord stimulation in refractory neuropathic pain secondary to herpes zoster.

Mesenchymal stem cells and thermal annular procedures for discogenic pain: a systematic review with pooled analysis.

Aim: Compare the effectiveness of mesenchymal stem cell injection therapies (MSC) and thermal annular procedures for the treatment of discogenic lower back pain. Materials & methods: A systematic review was performed following PRISMA 2020 guidelines. Pooled analysis was performed using patients' pain scores at baseline and at 12 months post-intervention. Results: Effect sizes based on change in pain score from baseline to 12 month follow-up revealed clinically significant improvement in pain score across all interventions. Conclusion: Minimally invasive interventions provide meaningful relief in discogenic back pain, with results suggesting promise for MSC injection therapies as a treatment model.

Bipolar, high-voltage, long-duration pulsed radiofrequency ablation of the Gasserian ganglion for the treatment of trigeminal neuralgia in a patient with a cardiac implantable electronic device: illustrative case.

BACKGROUND: One of the common methods of treating trigeminal neuralgia (TN) nowadays is radiofrequency therapy. However, it has serious limitations in patients with a cardiac pacemaker because of electromagnetic interference. Therefore, it is crucial to select optimal radiofrequency ablation parameters to make this procedure safe with favorable outcomes for such patients. OBSERVATIONS: In this study, the authors present a case of a 70-year-old man with a history of cardiac pacemaker dependency and previous microvascular decompression with complaints of severe, constant facial pain. After reprogramming the cardiac implantable electronic device (CIED), the authors performed bipolar, high-voltage, long-duration pulsed radiofrequency therapy (PRFT) of the Gasserian ganglion under electrocardiography and pulse rate control in the pre-, intra-, and postoperative periods. There were no cardiovascular or neurological complications after PRFT. The patient reported relief of pain after the procedure, and at the 9-month follow-up, he was pain-free. LESSONS: This clinical case demonstrates that the use of bipolar, high-voltage PRFT for TN treatment in patients with a CIED can be safe and effective, provided that the rules and pacemaker instructions are followed. It is necessary to use ablative treatment with caution and to guide the patient in collaboration with a cardiac surgeon and an anesthesiologist resuscitator.

Pulsed radiofrequency of lumbar dorsal root ganglion for lumbar radicular pain: A systematic review and meta-analysis.

BACKGROUND: Pulsed radiofrequency (PRF) of the lumbar dorsal root ganglion (DRG) has been widely used as a method to relieve lumbar radicular pain (LRP). However, the value of PRF application in LRP patients remains uncertain. This systematic review aimed to compare the effects of PRF of lumbar DRG and LEI in patients with LRP. METHODS: A literature search was performed using well-known databases for articles published up to May 2023. We included randomized controlled trials (RCTs) that evaluated the effects of PRF compared to LEI with or without steroids. We screened articles, extracted data, and assessed risk of bias in duplicate. The pain scores and Oswestry Disability Index (ODI) scores at 1, 3, and 6 months after procedures were obtained. A random-effects meta-analysis model was applied for outcomes. We evaluated evidence certainty for each outcome using the GRADE scoring system. This review was registered in the PROSPERO (ID: CRD42021253628). RESULTS: A total of 10 RCTs were included and data of 613 patients were retrieved. We assessed the overall quality of the evidence as very low to moderate. PRF showed no difference in pain scores at 1 (mean difference [MD] -0.80, 95% confidence interval [CI] -1.59 to 0.00, low certainty) and 6 months (MD -2.37, 95% CI -4.79 to 0.05, very low certainty), and significantly improved pain scores at 3 months (MD -1.31, 95% CI -2.29 to -0.33, low certainty). There was no significant difference in ODI score at any interval (very low to low certainty). In the subgroup who underwent a diagnostic block, did not use steroids, and PRF duration greater than 360 s, PRF significantly reduced pain scores at 3 months after procedures. CONCLUSIONS: We found low quality of the evidence supporting adjuvant PRF to the lumbar DRG has a greater analgesic effect at 3 months after procedures in patients with LRP than LEI. We identified no convincing evidence to show that this treatment improves function. High-quality evidence is lacking, and data were largely derived from short-term effects. Given these limitations, high-quality trials with data on long-term effects are needed.

Percutaneous Stylomastoid Foramen Pulsed Radiofrequency Combined with Steroid Injection for Treatment of Intractable Facial Paralysis After Herpes Zoster.

INTRODUCTION: We investigated the safety and efficacy of percutaneous facial nerve pulsed radiofrequency combined with drug injection for treatment of intractable facial paralysis of herpes zoster. The authors provide a detailed description of percutaneous facial nerve pulsed radiofrequency combined with steroid injection for treatment of intractable facial paralysis after herpes zoster, and they examine its clinical efficacy. This is the first time in the literature to our knowledge that this procedure has been applied in facial paralysis after herpes zoster. METHODS: A total of 43 patients with a history of facial paralysis after herpes zoster for > 1 month were enrolled in this retrospective study. The patients were subjected to percutaneous stylomastoid foramen pulsed radiofrequency of the facial nerve under computed tomography (CT) guidance combined with drug injection. The House-Brackmann grades and NRS (Numerical Rating Scale) data collection were performed at different time points (preoperatively, 1 day post-procedure, and 2, 4, and 12 weeks postoperatively). The occurrence of complications was also assessed. RESULTS: The 43 participants successfully completed the CT-guided percutaneous stylomastoid foramen pulsed radiofrequency of the facial nerve combined with drug injection. Both approaches [posterior approach of the ear (7 cases) and anterior approach of the ear (36 cases)] were efficacious and safe. The House-Brackmann grades (I, II, III, IV, V, VI) were 4 (3-4), 2 (2-3), 1 (1-2), and 1 (0-2) at different operation times (T0, T1, T2, T3, T4); patients felt significant recovery at T1 after operation and had gradually recovered at each time point but had no significant recovery after T3. The NRS scores at different operation times were 2.690 ± 2.213, 0.700 ± 0.939, 0.580 ± 1.006, 0.440 ± 0.908, and 0.260 ± 0.759, respectively. Differences in NRS scores between T0 and T1/2/3/4 were significant while differences between T1 and T2/3/4 were not significant. Six patients developed mild numbness, nine patients exhibited muscle tension, while one patient exhibited facial stiffness. During surgery, there was no intravascular injection of drugs, no nerve injury was reported, and there was no local anesthetic poisoning or spinal anesthesia. CONCLUSIONS: Percutaneous stylomastoid foramen pulsed radiofrequency combined with drug injection of the facial nerve for treatment of intractable facial paralysis after herpes zoster is a minimally invasive technique with high rates of success, safety, and effective outcomes. It is a potential therapeutic option for cases of facial paralysis of herpes zoster with a > 1 month history even for those with severe facial paralysis and whose treatment has failed after oral medication and physiotherapy.

Effect of CT-Guided Repeated Pulsed Radiofrequency on Controlling Acute/Subacute Zoster-Associated Pain: A Retrospective Cohort Study.

INTRODUCTION: Zoster-associated pain (ZAP) treatment and management is still inadequate. Repeated intervention protocol is often applied to manage ZAP. This study aimed to retrospectively investigate the effect of repeated applications of pulsed radiofrequency therapy on controlling acute/subacute ZAP. METHODS: From March 2019 to December 2021, 150 patients with acute/subacute ZAP who underwent repeated application of pulsed radiofrequency treatment (R-PRF) and pulsed radiofrequency combined paravertebral block interventions (PRF + PVB) in the Pain Department of the affiliated Hospital of Jiaxing University were enrolled. Patients were grouped by intervention protocol and received at least 12 months of follow-up assessments using the Numerical Rating Scale score (NRSs), Pittsburg Sleep Quality Index (PSQI), Simple McGill Pain Questionnaire-2 score (SF-MPQ-2s), and follow-up interventions. RESULTS: Both groups experienced a reduction in the incidence of clinically meaningful ZAP after the intervention therapy. In the R-PRF group, there were 36 cases of clinically meaningful ZAP within the first month post-treatment, while the PRF + PVB group had 38 cases. The incidence of clinically meaningful ZAP, as determined by multivariable generalized estimating equations, was 42.86% in the R-PRF group and 57.58% in the PRF + PVB group during the first month of follow-up. There was a significant difference in the incidence of clinically meaningful ZAP between the two groups after 1 month of treatment (adjusted odds ratio: 0.40; 95% confidence interval: 0.18-0.91; p = 0.03). CONCLUSIONS: Both R-PRF and PRF + PVB treatments effectively relieve pain in patients with acute/subacute ZAP. However, R-PRF may have superior efficacy compared to PRF + PVB in reducing the incidence of clinically meaningful ZAP 1 month after treatment.

Progress in Radiofrequency Therapy for Zoster-Associated Pain About Parameters, Modes, Targets, and Combined Therapy: A Narrative Review.

Zoster-associated pain (ZAP) is a painful condition that significantly impacts a patient's quality of life, often leading to postherpetic neuralgia (PHN). Over 30% of patients with herpes probably experience PHN. However, the understanding and treatment of ZAP remain inadequate. Common interventional treatments include radiofrequency therapy, nerve blocks, epidural block, and spinal cord electrical stimulation. Among these, radiofrequency therapy is widely used for pain control in ZAP, but the standard pulsed radiofrequency technique can still be improved. Researchers have explored different radiofrequency parameters, modes, targets, and combined treatments to enhance the therapeutic effect. In this paper, we review the latest research findings and incorporate our own departmental investigations. We conclude that high-voltage, long-duration pulsed radiofrequency and radiofrequency thermocoagulation therapy have shown improved therapeutic outcomes, despite some remaining limitations. Emphasis is placed on safety in intercostal nerve and extracranial nerve radiofrequency treatments. Combination therapy is also safe and effective; however, many studies have a low grade of evidence. Further high-quality research and systematic reviews are needed.