Evidence for Interventional Procedures as an Adjunct Therapy in the Treatment of Shingles Pain

A prospective randomized comparison of the efficacy of standard antiviral therapy versus ultrasound-guided thoracic paravertebral block for acute herpes zoster

OBJECTIVES

To evaluate the effectiveness of repetitive thoracic paravertebral block (TPVB) under ultrasound (US) guidance for acute pain associated to herpes zoster (HZ) and its prophylactic effects on post-herpetic neuralgia (PHN).

METHODS

Patients who suffered from acute pain associated to HZ within 1 week of rash onset were randomized in a ratio of 1:1 to receive a seven-day course antiviral therapy, antiviral therapy with additional US-guided repetitive TPVB using transverse short axial (TSA) approach every 48 h for a week after antiviral therapy. All patients were allowed to receive rescue analgesics. The primary endpoint was HZ burden of illness (HZ-BOI) measured by a severity-by-duration composite pain assessment conducted 1-month post inclusion. Adverse events were also recorded.

RESULTS

A total of 96 patients completed the entire 6-month follow-up. The BOI-30_AUC was 112.5 (95%CI: 105.2, 119.9) in control group, and 82.7 (95%CI: 75.4, 90.1) in TPVB group (F = 32.252, p<.001) at D30 after inclusion. Compared with control group, significant reductions of BOI-30-90_AUC, and BOI-90-180_AUC were observed in TPVB group (F = 11.392, p=.001 at D90; F = 7.467, p=.007 at D180, respectively). At 3 and 6 months after inclusion, the incidence of PHN in TPVB group was significantly lower than control group. Quality of life (QoL) in TPVB group also showed greater improvements at all the time points in all domains of EQ-5D-3L (p<.05). No serious adverse events were observed.

CONCLUSIONS

US-guided repetitive TPVB significantly reduced the HZ-BOI and the PHN incidence compared to antiviral therapy alone. It might be considered as an early intervention and preventive strategy to the development of PHN after acute HZ.KEY MESSAGEThis is a prospective randomized comparative study. We made a hypothesis that US-guided repetitive thoracic paravertebral block (TPVB) using a transverse short axial (TSA) approach to treat thoracic herpes zoster (HZ) in acute phase could reduce the burden of illness associated to acute pain. Moreover, this therapy might be a feasible preventive strategy to reduce the incidence of post-herpetic neuralgia.

Comparison of Two Different Pulsed Radiofrequency Modes for Prevention of Postherpetic Neuralgia in Elderly Patients With Acute/Subacute Trigeminal Herpes Zoster

OBJECTIVE

Trigeminal postherpetic neuralgia (PHN) is often refractory to treatment. Pulsed radiofrequency (PRF) neuromodulation can help in preventing PHN after herpes zoster. This study aimed to compare the efficacy and safety of two different PRF modes on gasserian ganglion neuromodulation in elderly patients with acute/subacute trigeminal herpes zoster.

MATERIALS AND METHODS

A total of 120 elderly patients with acute or subacute (within past three months) trigeminal herpes zoster were randomized to receive either a single cycle of high-voltage, long-duration PRF (HL-PRF group; N = 60) or three cycles of standard PRF (S-PRF group; N = 60). Patients were followed up for six months after treatment. Visual analog scale (VAS) pain score, 36-Item Short Form Health Survey (SF-36) score, and pregabalin at baseline and at different time points during follow-up were recorded.

RESULTS

VAS and SF-36 scores declined significantly from baseline levels in both groups (p < 0.001). The scores were significantly lower in the HL-PRF group than in the S-PRF group at some time points (p < 0.05). The mean dose of pregabalin was significantly lower in the HL-PRF group than in the S-PRF group on days 3, 14, and 28 after treatment (p < 0.05). No serious adverse events occurred in either group.

CONCLUSION

HL-PRF neuromodulation of the gasserian ganglion appears to be more effective than S-PRF for preventing PHN in the elderly.

CLINICAL TRIAL REGISTRATION

ChiCTR2000038775.

Analysis of Efficacy and Factors Associated with Reccurence After Radiofrequency Thermocoagulation in Patients with Postherpetic Neuralgia: a Long-Term Retrospective and Clinical Follow-Up Study

INTRODUCTION

Postherpetic neuralgia (PHN) is a painful condition that persists for 1 month or more after herpes zoster rash has healed. Radiofrequency thermocoagulation (RF-TC) provides analgesia by destroying the dorsal root ganglion and blocking the pain upload pathway; nonetheless, the concomitant neurological-related side effects and recurrence remain a concern.

METHODS

In this study, 228 patients with PHN in the thoracic segment treated with RF-TC of the dorsal root ganglion of the spinal nerve were included, and were followed up regularly after surgery. The numerical rating scale (NRS) scores, time to recurrence, and intraoperative and postoperative adverse events were recorded and analyzed. The Kaplan-Meier method was used to plot survival curves and calculate the cumulative effective rate and recurrence rate. Cox regression analyses were performed to identify factors associated with postoperative recurrence. Predictive models were built to assess the value of applications.

RESULTS

The NRS scores decreased in all postoperative periods compared with preoperative ones. At 10-year-follow-up, recurrence was observed in 34.6% (79/228) of patients that underwent PHN. The main postoperative complications were numbness and reduced abdominal muscle strength, which gradually decreased with time, while the abdominal muscle strength gradually recovered. No other adverse events occurred. Interval-censored multivariable Cox regression analysis demonstrated that disease course, complications, pain grade, and type of RF electrode were associated with a significantly higher risk of relapse. The main intraoperative adverse effect was a transient increase in pain during RF-TC.

CONCLUSION

CT-guided RF-TC of the dorsal root ganglion of the spinal nerve for PHN is a relatively safe and effective surgical option. Disease course, type of RF electrode, complications, and pain grade are risk factors for postoperative recurrence and can assist in clinical decision-making before the RF-CT procedure.

Effect of Ultrasound-Guided Intercostal Nerve Block Versus Fluoroscopy-Guided Epidural Nerve Block in Patients With Thoracic Herpes Zoster: A Comparative Study

OBJECTIVES

To compare the efficacy of a conventional fluoroscopy-guided epidural nerve block and an ultrasound (US)-guided intercostal nerve block in patients with thoracic herpes zoster (HZ).

METHODS

This work was a comparative study of 38 patients with thoracic HZ pain and a chest wall herpetic eruption, aged 18 years or older, with pain intensity of 5 or greater on a numeric rating scale (NRS) for less than a 1-month duration. Patients were consecutively enrolled and assigned to 2 groups in which the intervention was either the US-guided intercostal nerve block or the fluoroscopy-guided epidural nerve block approach with the addition of a 5-mL mix of 2.5 mg of dexamethasone plus 0.5% lidocaine. The primary outcome measure was the NRS score reduction for the pain. Secondary outcomes included the duration of treatment, number of repeated injections until the final visit, and proportion of patients with pain relief after the first and final visits.

RESULTS

All patients within both intervention groups showed significant pain relief on the NRS at the final follow-up point (P < .05). There was no significant difference in the mean value of NRS improvement based on the intervention type. There was also no statistically significant difference in the duration of treatment and the frequency of injection for pain relief.

CONCLUSIONS

These findings showed that both the US-guided intercostal nerve block and the fluoroscopy-guided epidural nerve block were effective in patients with thoracic HZ. Compared data showed no significant differences in the pain reduction, duration of treatment, and frequency of injection. The US-guided intercostal nerve block, which is more accessible than the fluoroscopy-guided epidural nerve block, might be an alternative option for thoracic HZ.

Treatment of postherpetic neuralgia using a thoracic transforaminal epidural steroid injection

A 64-year-old male patient with a history of herpes zoster exposure presented with severe, constant, burning pain in the left T10 dermatome consistent with postherpetic neuralgia. Previous treatment included oral and topical medications as well as an intercostal nerve block; however, these treatment options did not provide significant relief. The patient was treated with a single-level T10 thoracic transforaminal epidural steroid injection for refractory postherpetic neuralgia. He reported complete resolution of his symptoms at 2- and 12-week follow-ups. This case illustrates transforaminal epidural steroid injections may be a successful treatment option for postherpetic neuralgia.

Superficial cervical plexus block for management of herpes zoster neuralgia in the C3 dermatome: a case report

Introduction

Herpes zoster is a well-known reactivating viral disease that gives rise to painful skin lesions. Although this vesicular rash heals up within a few weeks, pain sometimes continues, becoming postherpetic neuralgia. In the case of those at high risk of developing postherpetic neuralgia, early interventional pain management is generally recommended as a preventive measure. Pain specialists usually do not see patients face-to-face for chronic refractory pain until the stage of postherpetic neuralgia. However, active and aggressive management, including antiviral treatment, of herpetic neuralgia during the acute stage of herpes zoster promises better results. In this respect, superficial cervical plexus block can help patients, such as the case reported here, by relieving the pain of herpes zoster involving the C3 dermatome.

Case presentation

A 65-year-old Korean man with severe pain in his left C3 dermatome due to herpes zoster was admitted to our hospital. His pain was so refractory to medication that he consulted our pain clinic for pain control. Due to the medication limitations imposed by his underlying diseases (hepatitis B, liver cirrhosis, atrial fibrillation, and asthma), early interventional therapy including stellate ganglion block was planned. In addition, because his painful C3 dermatome overlapped significantly with the superficial cervical plexus dermatome, ultrasound-guided superficial cervical plexus block was utilized for pain control of the intractable herpes zoster neuritis in his C3 dermatome. The result with respect to his sporadic neuralgia was satisfactory.

Conclusions

We found superficial cervical plexus block to be an effective interventional procedure for pain management of herpes zoster, particularly at the C3-dermatomal level.