Efficacy of ganglion impar block combined with pudendal nerve pulsed radiofrequency for pudendal neuralgia management-a randomized clinical trial.

BACKGROUND: Pudendal neuralgia is a chronic and debilitating condition. Its prevalence ranges from 5 to 26%. Currently, therapeutic approaches to treat pudendal neuralgia include patient education, medication management, psychological and physical therapy, and procedural interventions, such as nerve block, trigger point injections, and surgery. Drug therapy has a limited effect on pain relief. A pudendal nerve block may cause a significant decrease in pain scores for a short time; however, its efficacy significantly decreases over time. In contrast, pudendal nerve pulsed radiofrequency can provide pain relief for 3 months, and ganglion impar block has been widely used for treating chronic perineal pain and chronic coccygodynia. This study aimed to determine the efficacy and safety of monotherapy (pudendal nerve pulsed radiofrequency) and combination therapy (pudendal nerve pulsed radiofrequency plus ganglion impar block) in patients with pudendal neuralgia. METHODS: This randomized, controlled clinical trial will include 84 patients with pudendal neuralgia who failed to respond to drug or physical therapy. Patients will be randomly assigned into one of the two groups: mono or combined treatment groups. The primary outcome will be a change in pain intensity measured using the visual analog scale. The secondary outcomes will include a Self-Rating Anxiety Scale score, Self-Rating Depression Scale score, the use of oral analgesics, the Medical Outcomes Study Health Survey Short Form-36 Item score, and the occurrence of adverse effects. The study results will be analyzed using intention-to-treat and per-protocol analyses. Primary and secondary outcomes will be evaluated between the mono and combined treatment groups. Subgroup analyses will be conducted based on the initial ailment, age, and baseline pain intensity. The safety of the treatment will be assessed by monitoring adverse events, which will be compared between the two groups. DISCUSSION: This study protocol describes a randomized, controlled clinical trial to determine the efficacy and safety of mono and combination therapies in patients with pudendal neuralgia. The study results will provide valuable information on the potential benefits of this combination therapy and contribute to the development of more effective and safer treatments for patients with pudendal neuralgia. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2200061800).

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.

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.

Transforaminal pulsed radiofrequency and epidural steroid injection on chronic lumbar radiculopathy: A prospective observational study from a tertiary care hospital in Vietnam.

BACKGROUND: Lumbosacral radicular syndrome (LRS) is probably the most frequent neuropathic pain syndrome, exaggerating medical and economy burden on developing countries, such as Vietnam. As a result, the urgence to find an approach which is both affordable and effective always puts great demand on medical researchers. OBJECTIVES: Evaluate the effectiveness of transforaminal pulsed radiofrequency (PRF) stimulation on the dorsal root ganglion (DRG) and epidural steroid injection (ESI) in management of chronic lumbosacral radiculopathy. METHODS: Seventy-six patients with chronic radicular pain were performed transforaminal PRF + ESI by neurosurgeons. Demographic characteristics and surgical outcomes were recorded on admission, pre-procedural and post-procedural for 1-month, 3-month, 6-month and 12-month follow-up. Primary outcome was measured by using Visual Analogue Scale (VAS), Oswestry disability index (ODI) and Straight Leg Raising Test (SLRT). Secondary outcome was subjectively collected based on short assessment of patients' satisfaction (SAPS). RESULTS: Patients who received transforaminal PRF and ESI showed significant improvements on all three evaluation tools (VAS, ODI, SLRT), compared to that before treatment (p<0.001). Pain relief was achievable and long-lasting, which met patients' expectation. No significant complications were observed for 12 months follow-up. CONCLUSION: Transforaminal PRF combined with ESI in management of lumbosacral radiculopathy should be a good method of choice for its effectiveness and safety in management of pain.

Predictive value of S100B and brain derived neurotrophic factor for radiofrequency treatment of lumbar disc prolapse.

BACKGROUND: This work aimed to analyze serum S100B levels and brain-derived neurotrophic factor (BDNF) in patients with lumbar disc prolapse to test their predictive values concerning the therapeutic efficacy of pulsed radiofrequency. METHODS: This prospective interventional study was carried out on 50 patients candidates for radiofrequency for treating symptomatic lumbar disc prolapse. Pain severity and functional disability were assessed using the Numeric Rating Scale (NRS) and Functional rating index (FRI) before as well as two weeks, 1, 3, and 6 months after the radiofrequency. Quantitative assessment of serum S100B level and BDNF was done for all the included patients one day before radiofrequency. RESULTS: The scores of NRS and FRI were significantly improved at two weeks, 1, 3, and 6 months following radiofrequency (P-value < 0.001 in all comparisons). Statistically significant positive correlations were found between duration of pain, NRS, and S100B serum level before radiofrequency, and both NRS (P-value = 0.001, 0.035, < 0.001 respectively) and FRI (P-value = < 0.001, 0.009, 0.001 respectively) 6 months following radiofrequency. Whereas there were statistically significant negative correlations between BDNF serum level before radiofrequency and both NRS and FRI 6 months following radiofrequency (P-value = 0.022, 0.041 respectively). NRS and S100B serum levels before radiofrequency were found to be independent predictors of NRS 6 months following radiofrequency (P-value = 0.040. <0.001, respectively). CONCLUSION: Serum level of S100B is a promising biomarker that can predict functional outcomes after pulsed radiofrequency in patients with lumbar disc prolapse.

Combined Therapy of Paravertebral Nerve Pulsed Radiofrequency and Subcutaneous Block for Acute/Subacute Herpetic Neuralgia: A Retrospective Study.

OBJECTIVES: This retrospective study aimed to investigate the effectiveness and safety of early combined therapy with CT-guided paravertebral nerve (PVN), pulsed radiofrequency (PRF), and subcutaneous block on acute/subacute herpes zoster (HZ). METHODS: A total of 98 medical records were analyzed. All patients underwent CT-guided PRF on PVN immediately followed by a single subcutaneous block with lidocaine and dexamethasone in acute/subacute phase. The therapy efficacy was evaluated by pain numeric rating scale (NRS) and effective rate, which was defined as a percent of cases with a reduction in pain NRS>50% at day 1, week 2, 4, 12, and 24 after the procedure. The incidences of medication reduction and postherpetic neuralgia (PHN) were also retrieved. Further comparison was conducted between acute group (disease duration<30 days from HZ onset) and subacute group (30 day50% in prior medications amounted to 83% and the incidence of clinically meaningful PHN decreased to 23%. The clinical efficacy was more profound in acute group than in subacute group at every time points ( P <0.05). No severe complications occurred. DISCUSSION: Our data revealed surprising levels of pain relief by combination therapies of PRF and subcutaneous block targeting different sites of pain pathway, thus suggesting a valuable treatment option for acute/subacute herpetic neuralgia.

Comparing the effectiveness of pulsed radiofrequency treatment to lumbar dorsal root ganglion according to application times in patients with lumbar radicular pain: protocol for a randomised controlled trial.

INTRODUCTION: Lumbar radicular pain (LRP) is a common symptom characterised by a sharp, shooting or lancinating sensation localised to one or more dermatomes of the lumbar spine. Despite its high prevalence and significant impact on quality of life, the most effective conservative treatment for patients with LRP remains uncertain. When conventional treatment methods do not provide satisfactory results, the option of using epidural steroids and/or pulsed radiofrequency (PRF) treatment may be considered as a secondary approach for managing the condition. Ongoing advances in the field have led to a wide range of PRF parameters being investigated and extensively documented. Therefore, this study will aim to evaluate the treatment efficacy, sustainability and adverse effects of PRF application for different durations in patients with LRP. METHODS AND ANALYSIS: This study will be a double-blind, randomised, controlled trial. Eligible patients with LRP who visit the International St. Mary's Hospital pain clinic in Korea will be assigned to three groups (1:1:1 ratio) based on the duration of PRF application: 240, 360 and 480 s. Outcome measures will include an assessment of radicular pain intensity, physical function, global improvement, treatment satisfaction and adverse events. The primary outcome will be a Numeric Rating Scale (NRS) score 3 months after the procedure. The secondary outcomes will be the number of subjects in each group reporting successful treatment defined as a significant decrease of NRS or improved physical function score or high satisfaction at the 3 and 6 months follow-up. X2 or Fisher's exact test and one-way analysis of variance will be used to compare the outcomes. ETHICS AND DISSEMINATION: This trial was approved by the Ethics Committee of Catholic Kwandong University International St. Mary's Hospital (IS23EISE0018). The findings will be disseminated in peer-reviewed journals and at scientific conferences. TRIAL REGISTRATION NUMBER: KCT0008612.

Comparison of the efficacy of continuous radiofrequency thermocoagulation, pulsed radiofrequency denervation applications, and TENS therapies for lumbar facet syndrome: A single-blind randomized controlled trial.

OBJECTIVES: We aimed to compare the effectiveness of TENS, used in physical therapy departments, and continuous radiofrequency thermocoagulation (CRF) and pulsed radiofrequency denervation (PRF), used in algology departments, in patients with lumbar facet syndrome (LFS). METHODS: Subjects were selected from patients with LFS visiting outpatient clinics of physical therapy and algology departments at Ege University School of Medicine, whose pain was refractory to medical treatment for at least 3 months. Subjects were randomized into 3 groups. A total of 60 patients, with 20 in each group, were enrolled. The first group received CRF, the second group received TENS for 30 minutes a day for 15 days, and the third group received PRF. Patients were assessed at baseline, at the end of the first and sixth months, for a total of three times. RESULTS: Improvements at month 1 and month 6 were found to be statistically significant in all three treatment groups with respect to their pain scores, Oswestry Disability Indexes, hand-floor distance measurements, 20-meter walking times, 6-min walking distances, Beck Depression Inventory, and most of the SF-36 domain scores (p<0.05). A comparison of the treatment groups showed no superiority of any group over the others in any assessment parameters (p>0.05). CONCLUSION: We suggest that it might be more appropriate to use TENS, a non-invasive treatment, before trying more invasive procedures like CRF and PRF in these patients. However, it has been stated that further studies involving a larger patient sample are needed.

Evaluation of the efficacy of pulsed radiofrequency therapy in patients with lumbosacral radicular pain: An analysis of single-center data.

OBJECTIVES: Lumbosacral radicular pain (LRP) is one of the most common causes of neuropathic pain. This pain often arises from inflammation in the dorsal root ganglia (DRG) or spinal nerves. Despite various treatment modalities, success rates are not very high in chronic LRP cases. Pulsed radiofrequency (PRF) therapy, frequently applied to the DRG, is widely used, but its effectiveness is often questioned in various studies. The primary aim of our study is to evaluate the effectiveness of PRF treatment in 154 patients. METHODS: Patients with LRP for longer than 3 months, treated with PRF, were included in this study. To assess the efficacy of PRF treatment, numerical rating scale (NRS) scores were evaluated at the 4th-week and 6th-month follow-ups. RESULTS: The NRS scores were significantly lower at the 4th-week and 6th-month follow-ups compared to pre-treatment levels (p<0.001). However, there was no significant difference between the mean NRS scores at the 4th week and 6th month. CONCLUSION: Success in interventional pain procedures is often considered as at least a 50% reduction in pain scores. The success rate for PRF treatment for LRP in the literature varies between 30% and 60%, which is similar to our findings at the 4th week and 6th month. PRF treatment is widely used due to its low side-effect profile and cost-effectiveness in the long term. There is no fully standardized practice regarding procedural aspects, such as the duration of the application, and prospective studies with larger participation are needed.

Comparative Randomized Study Between Pulsed Radiofrequency and Suprascapular Nerve Block for the Treatment of Chronic Shoulder Pain.

OBJECTIVES: The primary objective of this study was to compare pain intensity after pulsed radiofrequency (RF) or suprascapular nerve block for the treatment of chronic shoulder pain. The secondary objectives were to compare the shoulder range of motion and supplementary analgesic requirement. METHODS: This randomized and prospective study included 40 patients, with chronic shoulder pain allocated into 2 groups. One group underwent pulsed RF, and the other group was submitted to block (B) of the suprascapular nerve, guided by ultrasound. They were assessed for 12 weeks regarding pain intensity, the need for analgesia supplementation, and shoulder range of motion. Side effects were recorded. RESULTS: Pain intensity on movement was lower in the RF group after 2, 4, and 8 weeks. At rest, pain intensity was lower in group RF than in group B after 12 weeks. Pain intensity was lower than before the procedure at all times evaluated, in both groups. There was no difference between groups in the range of motion. There was a need for tramadol supplementation in 1 patient in group RF and 2 in group B. Adverse effects observed were local pain (RF: 1), hematoma (RF: 1; B: 1), and lipothymia (B: 2). DISCUSSION: Pulsed RF on the suprascapular nerve promoted an analgesic effect for 12 weeks. Regarding the intensity of pain on movement and at rest, there was a trend toward a better effect with RF than with nerve blockage treatment. In both groups, there was a reduction in pain intensity without serious adverse effects.

Ozonated autohemotherapy combined with pulsed radiofrequency in the treatment of thoracic postherpetic neuralgia in older adults: a retrospective study.

Postherpetic neuralgia (PHN) seriously affects the quality of life of the elderly population. This study aimed to evaluate the efficacy of ozonated autohemotherapy (O3-AHT) combined with pulsed radiofrequency (PRF) in the treatment of thoracic PHN in older adults. The medical records of patients with thoracic PHN aged 65 years and older from June 2018 until March 2021 in Shengli Oilfield Central Hospital were reviewed. They were assigned into two groups: PRF alone (PRF group, n = 107) and PRF combined with O3-AHT (PRF + O3-AHT group, n = 109). Visual Analogue Scale for pain was evaluated at pre-treatment, 1 day, 1, 3 and 6 months after treatment. Quality of life and sleep quality were assessed using Short-Form 36 Health Survey and Athens Insomnia Scale at pre-treatment and 6 months post-treatment, respectively. The median age of patients in the PRF and PRF + O3-AHT groups were 69 (67-73) years and 68 (67-72) years, respectively. The former included 62 females and the latter included 51 females. Compared with pre-treatment, the Visual Analogue Scale scores of two groups declined at post-treatment. Patients in the PRF + O3-AHT group showed obviously lower Visual Analogue Scale scores compared with those in the PRF group at 1, 3, and 6 months after treatment and they had earlier withdrawal time for drugs. However, dizziness, tachycardia, sleepiness, and nausea were presented after combination therapy. These symptoms resolved spontaneously after a period of rest. Additionally, O3-AHT combined with PRF was associated with a significant decrease in the Athens Insomnia Scale score and with a significant improvement in every dimension of the Short-Form 36 Health Survey. To conclude, O3-AHT combined with PRF is an effective way to relieve thoracic PHN in older patients.

Pulsed radiofrequency on DRG inhibits hippocampal neuroinflammation by regulating spinal GRK2/p38 expression and enhances spinal autophagy to reduce pain and depression in male rats with spared nerve injury.

Evidence indicates that microglial G protein-coupled receptor kinase 2 (GRK2) is a key regulator of the transition from acute to chronic pain mediated by microglial products via the p38 mitogen-activated protein kinase (MAPK) pathway in the spinal cord dorsal horn (SCDH). Increasing studies have shown that autophagic dysfunction in the SCDH and neuroinflammation in the hippocampus underlie NeP. However, whether GRK2/p38MAPK and autophagic flux in the SCDH and hippocampal neuroinflammation are involved in NeP and depression comorbidity has not been determined. Here, we explored the effects of high-voltage pulsed radiofrequency (PRF) (85 V-PRF; HV-PRF) to the dorsal root ganglion (DRG) on pain phenotypes in Wistar male rats with spared nerve injury (SNI) and the underlying mechanisms. The exacerbation of pain phenotypes was markedly relieved by PRF-DRG. The SNI-induced reduction in GRK2 expression, elevation of p-p38 MAPK levels in the SCDH, and increase in IL-1ß and TNF-α levels in the hippocampus were reversed by PRF, which was accompanied by an increase in autophagic flux in spinal microglia. The beneficial effect of 85 V-PRF was superior to that of 45 V-PRF. In addition, the improvements elicited by 85 V-PRF were reversed by intrathecal injection of GRK2 antisense oligonucleotide, and these changes were accompanied by GRK2 downregulation and p-p38 upregulation in the SCDH, increased pro-inflammatory factor levels in the hippocampus, and excessive autophagy in spinal microglia. In conclusion, our data indicate that the application of HV-PRF to the DRG could serve as an excellent therapeutic technique for regulating neuroimmunity and neuroinflammation to relieve pain phenotypes.

Comprehensive Comparison of Therapeutic Efficacy of Radiofrequency Thermocoagulation and Pulsed Radiofrequency in Treatment of Elderly Patients with Thoracic Postherpetic Neuralgia.

BACKGROUND We comprehensively compared the therapeutic efficacy of radiofrequency thermocoagulation (RFT) and pulsed radiofrequency (PRF) in the treatment of elderly patients with thoracic postherpetic neuralgia (PHN). MATERIAL AND METHODS We divided 149 elderly patients with thoracic PHN into 2 groups - the RFT group (n=79) and the PRF group (n=70) - based on the radiofrequency mode administered. The Visual Analog Scale (VAS), Athens Insomnia Scale (AIS), Generalized Anxiety Disorder 7 items (GAD-7), and Patient Health Questionnaire 9 items (PHQ-9) were used to analyze the degree of pain, sleep quality, and psychological state of patients before and 1 week, 1 month, 3 months, 6 months, and 12 months after treatment. RESULTS VAS, AIS, GAD-7, and PHQ-9 scores were significantly decreased after RFT and PRF treatment (P<0.001). There was no significant difference in VAS scores between the 2 groups at 1 week and 1 month after treatment (P>0.05). Then, VAS scores in the RFT group were significantly lower than those in the PRF group at 3, 6, and 12 months after treatment (P<0.001). At 1 week after treatment, there were no significant differences in AIS, GAD-7, and PHQ-9 scores between the 2 groups (P>0.05). However, the RFT group had significantly lower AIS, GAD-7, and PHQ-9 scores than the PRF group at 1, 3, 6, and 12 months after treatment (P<0.05). CONCLUSIONS RFT and PRF both effectively reduced pain in the distribution area of thoracic spinal neuropathy and improved the sleep quality and psychological state of elderly patients with thoracic PHN, but RFT had a better long-term effect.

Output Current and Efficacy of Pulsed Radiofrequency of the Lumbar Dorsal Root Ganglion in Patients With Lumbar Radiculopathy: A Prospective, Double-blind, Randomized Pilot Study.

BACKGROUND: Lumbar radicular pain (LRP) is a common but challenging clinical symptom. Pulsed radiofrequency (PRF), a neuromodulation technique that uses short pulses of radiofrequency current, is effective in treating various pain disorders. However, few studies have been conducted on the effects of PRF and its modifying parameters. OBJECTIVES: Our study aimed to determine the intraoperative parameters of PRF of the lumbar dorsal root ganglion (DRG) that are related to clinical effects in patients with LRP unresponsive to transforaminal epidural steroid injections (TFESI). STUDY DESIGN: Prospective double-blind randomized controlled trial, pilot study. SETTING: Single medical center in the Republic of Korea. METHODS: Patients were allocated to one of 2 groups, high-voltage (60 V) or standard-voltage (45 V), according to the preset maximum voltage at which the active tip temperature does not exceed 42°C. Intraoperative parameters, such as output current, sensory threshold, and impedance, were measured. The primary outcomes were radicular pain intensity, physical functioning, global improvement and satisfaction with treatment, and adverse events. The assessments were performed up to 3 months postprocedure. RESULTS: The patients in the standard-voltage group showed significant improvements in the Numeric Rating Scale pain score (P = 0.007) and Oswestry Disability Index (ODI) (P = 0.008) scores at 3 months post-PRF; however, no difference was observed in the high-voltage group. Among the intraoperative parameters, the output current showed a significant negative linear relationship with analgesic efficacy. The output current also showed a significant association with pain intensity (P = 0.005, R2 = 0.422) and ODI score (P = 0.004, R2 = 0.427) at 3 months postprocedure in a multiple regression analysis. The optimal cut-off value of the output current to lower pain intensity after 3 months was 163.5 mA with a sensitivity of 87.5%, specificity of 100%, and an area under the receiver operating characteristic curve value of 0.92 (95% CI. 0.76 - 1.00). LIMITATIONS: Limitations of our study include an imbalance of baseline characteristics, small sample sizes, and short follow-up periods. CONCLUSIONS: Lower output currents during PRF application to the lumbar DRG were associated with greater analgesic effects in patients who did not respond to therapeutic TFESI.

Implicación ocular en el tratamiento con radiofrecuencia pulsada del ganglio esfenopalatino / Ocular involvement in sphenopalatine ganglion pulsed radiofrequency

El tratamiento con radiofrecuencia pulsada del ganglio esfenopalatino es una opción importante a tener en cuenta respecto al tratamiento intervencionista en casos refractarios de neuralgia del trigémino o dolores faciales atípicos, dado el fácil acceso a su localización. A pesar de que las complicaciones de esta técnica son raras y es un procedimiento bastante seguro, a nivel oftalmológico cabe reseñar su importancia por las relaciones anatómicas de este ganglio (AU)

Pulsed radiofrequency treatment of the sphenopalatine ganglion is an important interventional treatment in refractory cases of trigeminal neuralgia or atypical facial pain, given the easy access to its location. Despite the fact that complications from this technique are rare and it is a fairly safe procedure, ophthalmologists should know about it due to the anatomical relations of this ganglion (AU)

Comparisons of the analgesic effect of different pulsed radiofrequency targets in SNI-induced neuropathic pain.

An injury of the peripheral nerve may lead to neuropathic pain, which could be treated with pulsed radiofrequency to the dorsal root ganglion (DRG) or peripheral nerve [the nerve trunk (NT) or proximal to the injury site (NI)]. However, it is not clear whether there is any difference in analgesic effect or maintenance among the three targets. PRF was applied to the ipsilateral L5 DRG, peripheral nerve (NT or NI) 5 days after spared nerve injury (SNI). Triptolide (10 µg/kg) or vehicle was intrathecally administered 5 days after SNI for 3 days. Mechanical withdrawal thresholds were tested after treatment at different time points. Furthermore, microglia and the P2X7 receptor (P2X7R) in the ipsilateral spinal cord were measured with immunofluorescence and western blotting, respectively. PRF + NI exerted a more remarkable analgesic effect than PRF + DRG and PRF + NT at the early stage, but PRF + DRG had a stronger analgesic effect than PRF + NI and PRF + NT at the end of our study. In addition, PRF + DRG showed no significant difference from intrathecal administration of triptolide. Moreover, SNI-induced microglia activation and upregulation of P2X7R in spinal dorsal horn could be markedly inhibited by PRF + DRG. The results suggest that the analgesic effect of PRF + DRG increased with time whereas the other two not and microglia and P2X7R in the ipsilateral spinal dorsal horn may be involved in the process.

[Efficacy and safety of high-voltage pulsed radiofrequency combined with pregabalin on severe thoracic postherpetic neuralgia].

Objective: To investigate the efficacy and safety of high-voltage pulse radiofrequency combined with pregabalin on severe thoracic postherpetic neuralgia (PHN). Methods: A total of 103 patients with PHN who were admitted to the Department of Pain Medicine of Henan Provincial People's Hospital from May 2020 to May 2022 were retrospectively selected, including 50 males and 53 females, and aged 40 to 79 (65.4±9.2) years. The patients were divided into two groups according to the treatment methods they received: the control group (n=51) and the study group (n=52). The patients in the control group were treated with oral pregabalin, and the patients in the study group received pregabalin plus high-voltage pulse radiofrequency therapy. The pain intensity and efficacy of the two groups were evaluated before treatment and 4 weeks after treatment. The pain intensity, the sleep quality and the efficacy of treatment was evaluated by visual analogue scale (VAS) score, Pittsburgh Sleep Quality Index (PSQI) score and nimodipine method, respectively. The levels of pain factors including serum neuropeptide Y (NPY), prostaglandin E2 (PGE2), substance P (SP) and ß-Endorphin were measured. The differences of the above indicators and the incidence of adverse reactions were compared between the two groups. Results: The VAS scores and PSQI scores of the study group and the control group before treatment were (7.94±0.76), (8.20±0.81), (16.84±3.90) and (16.29±3.84), respectively, with no statistically significant difference (both P>0.05). After 4 weeks of treatment, the VAS scores and PSQI scores of the two groups were (2.84±0.80), (3.35±0.87), (6.78±1.90) and (7.98±2.40), respectively, and the VAS score and PSQI score in the study group were lower than those in the control group (both P<0.05). Serum levels of NPY, PGE2, SP and ß-Endorphin were (298.5±31.0) ng/L, (92.3±11.0) µg/L, (156.8±21.4) ng/L, and (8.6±1.6) ng/L in the study group and (304.2±28.6) ng/L, (94.4±12.9) µg/L, (152.7±23.8) ng/L and (8.2±1.8) ng/L in the control group, with no significant differences (all P>0.05). After 4 weeks of treatment, levels of NPY, PGE2, SP and ß-Endorphin were (240.7±26.8) ng/L, (74.4±8.6) µg/L, (108.9±15.7) ng/L and (4.4±0.9) ng/L, which were lower than those in the control group [(268.1±29.4) ng/L, (79.7±8.3) µg/L, (115.2±16.2) ng/L, (5.2±1.3) ng/L, respectively], with statistically significant differences (all P<0.05). After treatment, 29 cases were cured, 16 cases were markedly effective and 6 cases were effective in the study group, while 16 cases, 24 cases and 8 cases were cured, markedly effective and effective in the control group. The overall efficacy of patients in the study group was better than that in the control group (Z=-2.32, P=0.018). The incidence of adverse reactions in the study group and control group was 11.5% (6/52) and 7.8% (4/51), respectively, with no statistically significant difference (χ2=0.40, P=0.527). Conclusion: High-voltage pulse radiofrequency combined with pregabalin can significantly improve the pain and sleep quality of patients with severe thoracic PHN and reduce the level of pain factors, with a high safety profile.

Effectiveness and safety of high-voltage pulsed radiofrequency to treat patients with primary trigeminal neuralgia: a multicenter, randomized, double-blind, controlled study.

BACKGROUND: Trigeminal neuralgia (TN) is a debilitating pain disorder that still lacks an ideal treatment option. Pulsed radiofrequency (PRF), especially with high output voltage, is a novel and minimally invasive technique. PRF is regarded a promising treatment option for TN patients who respond poorly to medical treatment; however, the available evidence still lacks high quality randomized controlled trials (RCTs). Our study aimed to evaluate the long-term (1 year and 2 years) effects and safety of high-voltage PRF in primary TN patients and provide stronger evidence for TN treatment options. METHODS: We performed a multicenter, double-blind, RCT in adults (aged 18-75 years) with primary TN who responded poorly to drug therapy or were unable to tolerate the side effects of drug. Eligible participants were randomly assigned (1:1) to receive either high voltage PRF or nerve block with steroid and local anesthetic drugs. The primary endpoint was the 1-year response rate. This trial has been registered in the clinicaltrials.gov website (registration number: NCT03131466). RESULTS: One hundred and sixty-two patients were screened for enrollment between April 28th,2017 and September1st, 2019, among whom, 28 were excluded. One hundred and thirty-four participants were randomly assigned to either receive high voltage PRF (n = 67) or nerve block (n = 67). The proportion of patients with a positive response at 1-year after the procedure in the PRF group was significantly higher than that in the nerve block group in the intention-to-treat population (73.1% vs. 32.8%, p < 0.001). There was no difference between groups in the incidence of adverse events. CONCLUSIONS: Our findings support that high voltage PRF could be a preferred interventional choice prior to receiving more invasive surgical treatment or neuro-destructive treatment for TN patients who have poor responses to medical treatment. TRIAL REGISTRATION: Our study has been registered at ClinicalTrials.gov (trial registration number: NCT03131466).

Ocular involvement in sphenopalatin ganglion pulsed radiofrequency.

Pulsed radiofrequency (PRF) treatment of the sphenopalatine ganglion is an important interventional treatment in refractory cases of trigeminal neuralgia (TN) or atypical facial pain, given the easy access to its location. Despite the fact that complications from this technique are rare and it is a fairly safe procedure, ophthalmologists should know about it due to the anatomical relations of this ganglion.

Clinical study of puncture technique in single division of the trigeminal ganglion intumescentia.

OBJECTIVE: We explored the feasibility of single-division puncture in the ophthalmic division, maxillary division, and mandibular division of the trigeminal ganglion intumescentia (TGI) and the feasibility of radiofrequency treatment of trigeminal neuralgia. METHODS: According to the previous anatomical image studies, 3D Slicer software was used to analyze the CT images of the patients. The trigeminal ganglion fossa (TGF) was used as the imaging sign. TGI was identified in the sagittal plane along the fiber. The puncture path starts from the TGI center-foramen ovale line, extending outward to the epidermis as the needle insertion point, and extending inward to the division boundary. For lateral puncture, which is blocked by the mandible, the positions of closed mouth, open mouth, and over-open mouth were used. Multiple targets were generated using straight electrodes and curved electrodes to achieve full coverage of TGI. According to the preoperative design, general anesthesia surgery was performed. Xper CT was used for imaging, and the puncture was guided by Xper Guide. Radiofrequency treatment of TGI was conducted. RESULTS: In total, 45 patients with trigeminal neuralgia underwent 50 single-division TGI punctures. The procedure was smooth and the compliance with the design was good. Continuous radiofrequency (CRF) was performed, the VAS scores were 25 times at 70°C, 19 times at 65°C, two times at 60°C, and two times at 50°C (both in the ophthalmic division). Pulsed radiofrequency (PRF) was conducted two times. Within 24 h after the procedure, the VAS scores were all 0. From 1 to 7 days after the procedure, pain recurrence was found in three cases, of whom two cases received pulsed radiofrequency treatment. Patients were followed up for 1-24 months and there were no recurrence. After continuous radiofrequency at 65-70°C, the moderate tactile loss was observed, and nearly half of the patients had food residues on the surgical side after 6 months. After continuous radiofrequency at 60°C, there was mild tactile loss and no food residue. The tactile sensation was slightly decreased after continuous radiofrequency at 50°C, and the tactile sensation was normal the next day. CONCLUSION: Trigeminal ganglion intumescentia single-division radiofrequency is effective and feasible for the treatment of trigeminal neuralgia.