Efficacy of Dorsal Root Ganglion Pulsed Radiofrequency Combined with Paravertebral Injection of Recombinant Human Interferon-α2b in Herpetic Neuralgia

Identifying and Evaluating Biological Markers of Postherpetic Neuralgia: A Comprehensive Review

Postherpetic neuralgia (PHN) manifests as persistent chronic pain that emerges after a herpes zoster outbreak and greatly diminishes quality of life. Unfortunately, its treatment efficacy has remained elusive, with many therapeutic efforts yielding less than satisfactory results. The research to discern risk factors predicting the onset, trajectory, and prognosis of PHN has been extensive. However, these risk factors often present as nonspecific and diverse, indicating the need for more reliable, measurable, and objective detection methods. The exploration of potential biological markers, including hematological indices, pathological insights, and supportive tests, is increasing. This review highlights potential biomarkers that are instrumental for the diagnosis, management, and prognosis of PHN while also delving deeper into its genesis. Drawing from prior research, aspects such as immune responsiveness, neuronal injury, genetic makeup, cellular metabolism, and pain signal modulation have emerged as prospective biomarkers. The immune spectrum spans various cell subtypes, with an emphasis on T cells, interferons, interleukins, and other related cytokines. Studies on nerve injury are directed toward pain-related proteins and the density and health of epidermal nerve fibers. On the genetic and metabolic fronts, the focus lies in the detection of predisposition genes, atypical protein manifestations, and energy-processing dynamics, with a keen interest in vitamin metabolism. Tools such as functional magnetic resonance imaging, electromyography, and infrared imaging have come to the forefront in the pain signaling domain. This review compiles the evidence, potential clinical implications, and challenges associated with these promising biomarkers, paving the way for innovative strategies for predicting, diagnosing, and addressing PHN.

Efficacy and Safety of Pulsed Radiofrequency of Dorsal Root Ganglion in Elderly Patient Population With Acute and Subacute Zoster-Related Pain

Background: Herpes zoster (HZ) is typically characterized by a burning, stabbing pain, hyperalgesia, and allodynia. In some patients, despite the lesions resolving, the pain persists and becomes chronic. If the pain continues for more than 6 months after the onset of the pain phase, this condition is called postherpetic neuralgia (PHN). The frequency and severity of PHN increase with advancing age. The pain in PHN can be severe, sometimes resistant to medications, significantly impacting the patients' quality of life. The elderly patient population cannot tolerate the medications due to their side effects. In this situation, interventional pain treatment should be applied in the elderly patient group who have a high risk of developing PHN compared to other age groups. Method: We included patients over 65 years of age with HZ-related pain who underwent dorsal root ganglion (DRG) pulsed radiofrequency (PRF) within the first 6 months from the onset of pain. We divided these patients into 2 groups: patients who underwent intervention within the first 1 month from the onset of pain and patients who underwent intervention between 1 and 6 months. We recorded medication doses and Numeric Rating Scale (NRS) scores before the procedure and at 1 week, 1 month, 3 months, and 6 months after the procedure. Results: After the DRG PRF treatment, NRS scores improved significantly in both groups (p < 0.05). The mean NRS score in the early DRG PRF group was significantly lower than that in the late DRG PRF group (p < 0.05). The medication doses in the early DRG PRF group were significantly lower than those in the other group (p < 0.05). Conclusions: Interventional pain treatment should be applied as soon as possible in the elderly patient group who do not respond to first-line medical treatment or cannot tolerate medical treatment due to its side effects and who have a high risk of developing PHN compared to other age groups. DRG PRF, applied in the early period of medical treatment-resistant acute HZ, is safe and effective, preventing the progression to PHN.

Clinical efficacy of high-voltage pulsed radiofrequency combined with stellate ganglion block in the acute phase of thoracic and dorsal herpes zoster neuralgia under dual guidance of ultrasound and C-arm

OBJECTIVES

A single therapeutic approach is not always successful in the treatment of herpes zoster neuralgia, and the appropriate combination of different treatments deserves further exploration. In this study, we investigated the clinical efficacy of high-voltage long-duration pulsed radiofrequency (PRF) combined with stellate ganglion block (SGB) in the acute phase of thoracic and dorsal herpes zoster neuralgia under dual guidance of ultrasound and C-arm.

METHODS

79 cases of acute zoster neuralgia were grouped premised upon differing therapeutic approaches: standard voltage PRF (group S, the temperature, duration, pulse width, frequency and voltage were set to 42 °C, 300 s, 20 ms, 2 Hz, and 45 V), high-voltage long-duration PRF (group H, parameters of PRF were set to 42 °C, 900 s, 20 ms, 2 Hz, and 90 V, respectively), and high-voltage long-duration PRF combined with SGB (group C, parameter settings for PRF are the same as those for group H). The therapeutic outcomes were assessed utilizing the numeric rating scale (NRS), Pittsburgh sleep quality index (PSQI), and Hamilton anxiety rating scale (HAMA). The incidence of clinically significant postherpetic neuralgia post-treatment had been documented.

RESULTS

Compared to baseline, scores of NRS, PSQI, and HAMA at each time point post-treatment decreased across all groups, and the decrease was more significant in the C group than in the S group. At the later stage of treatment, the consumption of pregabalin and tramadol and the plasma levels of interleukin-6 and galectin-3 in the C group were significantly lower than those in the S group. The incidence of PHN in the C group was significantly lower than in the S group.

CONCLUSIONS

The combination of high-voltage long-duration PRF combined with SGB under dual guidance of ultrasound and C-arm represents a safe, effective, environmentally friendly, and cost-efficient method for treating AZN, significantly improving sleep quality, alleviating anxiety, and reducing the risk of PHN occurrence.

Outcomes of Twice Repeated High-Voltage Long-Duration Pulsed Radiofrequency Treatment in Subacute Postherpetic Neuralgia: a Retrospective Single-Center Analysis

Background

The treatment of herpes zoster-related pain is challenging, and requires a variety of methods including pulse radio frequency modulation. Among them, single-time high-voltage long-term pulsed radiofrequency (HL-PRF) has been proved to be an effective treatment for subacute postherpetic neuralgia. However, it has the possibility of poor long-term curative effect and recurrence of neuralgia. In this study, we aim to identify the clinical efficacy and safety of twice repeated HL-PRF treatment in patients with subacute postherpetic neuralgia.

Design

We conducted a retrospective analysis of subacute postherpetic neuralgia patients who underwent HL-PRF treatment.

Setting

Pain Management Department of First Affiliated Hospital of Wannan Medical College.

Patients

We enrolled all patients with subacute postherpetic neuralgia, who underwent HL-PRF treatment from January 2023 to October 2023.

Measurements

The primary outcome variable was the visual Analog Scale (VAS) scores at 1, 4, 8, and 12 weeks after treatment. Secondary outcomes included Pittsburgh sleep quality index (PSQI), 36-item short-form health survey (SF-36) score, and total effective rate after treatment.

Results

A total of 63 patients were included in the analysis. Among them, 33 patients received single-time HL-PRF treatment (Group S) and 30 patients received twice repeated HL-PRF treatment (Group T). Pain scores, PSQI scores, and SF-36 score were reduced in both groups after treatment (P < 0.001). Compared to group S, the VAS scores, PSQI scores, anxiety scores, and depression scores were significantly lower at 1, 4, 8, and 12 weeks in group T. (P < 0.001). The total efficiency rate at 12 weeks after treatment of group T was statistically higher than that of group S (60.6% vs 86.7%, P < 0.05).

Conclusion

Twice repeated high-voltage long-duration PRF therapy demonstrates satisfactory efficacy in patients with subacute postherpetic neuralgia and is associated with no significant adverse reactions.

Comparing the efficacy and safety of high-voltage and standard-voltage pulsed radiofrequency for the treatment of postherpetic neuralgia: A pooled analysis from randomized controlled trials

Postherpetic neuralgia (PHN) is one of the most common and serious complications of herpes zoster infection. Pulsed radiofrequency (PRF) therapy has emerged to be a neuromodulation technique for the treatment of PHN. Two therapeutic options are available for PRF, including high-voltage and standard-voltage PRF. Some studies suggested that the former one had better clinical efficacy than the latter one. For the first time, this pooled analysis compared the efficacy and safety of these two surgeries for the treatment of PHN. Five commonly used databases were applied to identify the eligible studies. This study was registered on the PROSPERO (ID: CRD42023460236), which provided more relevant information. Finally, four randomized controlled trials (RCTs) with 285 participants were included. The combined odds ratios (OR) showed that high-voltage PRF exhibited a significantly higher treatment efficiency than the standard PRF (OR = 1.4, 95%CI: 1.16 to 1.69, P < 0.001). Additionally, the visual analogue scale (VAS) in the high-voltage PRF group was significantly lower than that of the standard PRF group at one week (SMD = -0.776, 95%CI: -1.408 to -0.145, P = 0.016), one month (SMD = -0.544, 95%CI: -0.907 to -0.180, P = 0.003), and three months (SMD = -1.096, 95%CI: -1.504 to -0.687, P < 0.001) after treatment, particularly at the three months after surgery. However, the VAS was comparable between the two groups (SMD = -0.94, 95%CI: -1.985 to 0.104, P = 0.077). Patients who underwent high-voltage PRF did not have a significantly higher incidence of adverse events than those with standard PRF (OR = 1.56, 95%CI: 0.78 to 3.13, P = 0.208). In summary, the current study revealed that high-voltage PRF is superior to standard-voltage PRF in improving analgesic efficacy in patients with PHN. Additionally, it does not increase the incidence of treatment-related adverse effects. Further studies are still warranted to determine the optimal voltage and duration of PRF treatment for patients with PHN.

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 day

RESULTS

Early combined therapy indicated an immediate and sustained improvement in pain NRS as compared with before treatment ( P <0.0001), with effective rates of 74%, 79%, 80%, 76%, and 79% at day 1, week 2, 4, 12, and 24 after procedure, respectively. At the end of follow-up, the proportion of patients with a reduction of >50% 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.

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Key Words Collapse

MESH Headings

• Humans
• Retrospective Studies
• Pulsed Radiofrequency Treatment/methods
• Neuralgia/complications
• Neuralgia, Postherpetic/therapy
• Herpes Zoster/complications
• Herpes Zoster/therapy

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Grants Collapse

Affiliation(s)

Wei Zhang Departments of Day Surgery
Bin Yu Departments of Day Surgery
Zipu Jia Departments of Day Surgery
Chunmei Zhao Day Surgery and Pain Management, Beijing Tiantan Hospital, Capital Medical University, Beijing, PR China
Fang Luo Day Surgery and Pain Management, Beijing Tiantan Hospital, Capital Medical University, Beijing, PR China

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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.

Early Diagnosis of Herpes Zoster Neuralgia: A Narrative Review

BACKGROUND

Early intervention reduces the incidence of postherpetic neuralgia (PHN). Typical shingles are easy to diagnose; however, there is no clear diagnostic method for neuralgia symptoms manifested before the onset of the rash, which can easily cause misdiagnosis. This not only increases the patient's pain, medical expenses, and mental burden, but more importantly, delays the valuable time for early treatment of shingles, and increases the probability of complications and PHN.

OBJECTIVE

In this paper, the diagnostic methods of preherpetic neuralgia were summarized and analyzed, and the current challenges were put forward to provide directions for the early diagnosis of herpes zoster (HZ) in the future.

METHODS

PubMed, and China National Knowledge Infrastructure (CNKI) libraries were searched using the terms "herpes zoster," "before the blistering," "diagnosis," and "neuralgia." Clinical trials, reviews, and case reports were collected and reviewed. The period of literature search is from 1 January 1980 to 1 October 2022.

RESULTS

The early diagnosis of herpes zoster neuralgia can reduce misdiagnosis and mistreatment, and timely and effective intervention can significantly reduce the incidence of PHN. The body may possess a mechanism that limits the local breakthrough of the virus in the skin, causing blistering later than the onset of pain. Changes in the plasma proteins of patients with varicella-zoster virus shingles neuralgia may be used as an early diagnostic indicator in patients with HZ neuralgia before eruption.

CONCLUSION

Early diagnosis of HZ neuralgia before eruption can facilitate timely targeted treatment, thereby reducing the incidence of PHN. Proteomic quantitative analysis and validation results can serve as a simple, micro, rapid, and accurate diagnostic method.

Efficacy of Internal Heat Acupuncture Combined with High-Voltage Long-Duration Pulsed Radiofrequency on Subacute Postherpetic Neuralgia: A Retrospective Study

Objectives

This study aims at investigating the internal heat acupuncture (IHA) combined with the high-voltage long-duration pulsed radiofrequency (PRF) therapeutic effect on subacute postherpetic neuralgia (PHN).

Methods

This retrospective study comprised 81 cases with PHN. They were divided into three groups: IHA combined with the high-voltage long-duration PRF group (IHA-PRF), intradermal injection combined with the high-voltage long-duration PRF group (II-PRF), and the high-voltage long-duration PRF group. The pain numerical rating score (NRS), IL-6, Gal-3, and blood glucose levels were recorded before and after treatment.

Results

Compared with before treatment, NRS scores of the three groups were all decreased at each time point. NRS scores of the IHA-PRF group patients decreased significantly in comparison to the PRF group at 1, 4, 8, and 12 weeks following treatment, while group II-PRF only decreased significantly at one week following treatment. Compared with groups II-PRF and PRF, respectively, IL-6 and Gal-3 levels in plasma of patients in group IHA-PRF were significantly decreased at 4 and 12 weeks after treatment. The effective rate of group IHA-PRF was 88.9%, which was considerably more than the other groups, II-PRF (63.0%) and PRF (63.0%). Compared with group II-PRF, patients' blood glucose levels in IHA-PRF and PRF groups significantly decreased three days and one week after treatment.

Conclusion

Internal heat acupuncture combined with high-voltage long-duration pulsed radiofrequency has a satisfactory therapeutic effect on subacute PHN and has no obvious adverse reactions, which is especially suitable for patients with poor blood glucose control.

Clinical Efficacy of Pulsed Radiofrequency Combined with Intravenous Lidocaine Infusion in the Treatment of Subacute Herpes Zoster Neuralgia

Objective

Under the guidance of a digital subtraction angiography (DSA) machine, via fluoroscopic imaging techniques, patients diagnosed with herpes zoster neuralgia at the subacute stage, where self-reported pain lasts between 30 and 90 days, were treated with nerve pulsed radiofrequency surgery combined with intravenous lidocaine infusion or saline infusion as control. This study explores the clinical efficacy, safety, and clinical value of the combined treatment compared with nerve pulsed radiofrequency surgery alone.

Methods

In this study, 72 patients diagnosed with herpes zoster neuralgia at the subacute stage were randomly divided into two groups with matched gender, age, and clinical symptoms. Both groups received pulsed radiofrequency surgery for the affected nerve segments under DSA fluoroscopy. Five days after the operation, 0.9% saline was administered daily for five consecutive days (50 ml per day, intravenous infusion) to group A (n = 36), and lidocaine was administered daily for five consecutive days (3 mg per kg per day, intravenous infusion) to group B (n = 36). Patients with poor pain control during the treatment were given 10 mg morphine tablets for pain relief to reach visual analog scale (VAS) ≤4 points. Data of the following categories were collected: VAS score, self-rating anxiety scale (SAS) score, depression self-rating scale (SDS) score, Pittsburgh sleep quality score (PSQI), 45 body area rating scale score, skin temperature measurement using infrared thermography, analgesic drug use before and after treatment at six different time points: before surgery (T₀), one day after surgery (T₁), three days after surgery (T₂), five days after surgery (T₃), one month after surgery (T₄), and two months after surgery (T₅). Blood was collected from all patients in the morning before surgery and right after the last intravenous infusion of lidocaine at T₃. Serum inflammatory indexes including white blood cell count, lymphocyte count, neutrophils count, erythrocyte sedimentation rate count, C-reactive protein (CRP) level, calcitonin gene-related peptide (CGRP) level, and interleukin-6(IL-6) level were determined. Lastly, the incidence of complications and adverse reactions throughout the study was recorded.

Results

In total, 64 out of 72 patients completed the whole study. Two patients met the exclusion criteria in group A, one patient refused to participate, and one was lost to follow-up. Two patients met the exclusion criteria in group B, and two were lost to follow-up. Three patients in group B experienced vomiting during lidocaine treatment. The adverse symptom was relieved after symptomatic treatment. No patients in the two groups had severe complications such as hematoma at the puncture site, pneumothorax, and nerve injury. Compared with before treatment, the mean of VAS score, SAS score, SDS score, PSQI score, and skin temperature of both groups at each time point after interventional surgery were all significantly reduced. Furthermore, at each time point after surgery, the above indicators of group B patients were significantly lower than those of group A patients. After treatment, the consumption of analgesics in both groups was significantly lower than before treatment. Compared with group A, the consumption of analgesics was also significantly lower in group B. In addition, serum inflammatory indexes at the T₃ time point of the two groups of patients were lower than T₀. Among them, the erythrocyte sedimentation rate, CRP level, CGRP level, and interleukin-6 level of group B were significantly lower than those of group A. The incidence of postherpetic neuralgia (PHN) in group B patients (6.25%) was also lower than that in group A patients (25%).

Conclusion

DSA-guided nerve pulse radiofrequency surgery combined with intravenous lidocaine infusion can effectively relieve pain in patients diagnosed with herpes zoster nerves at the subacute stage, reduce the number of analgesic drugs used in patients, reduce postherpetic neuralgia incidence rate, and improve sleep and quality of life.