Does Instability during Standing Occur just after Transcutaneous Xenon Light Irradiation around the Stellate Ganglion?

Effects of Linearly Polarized Near-Infrared Irradiation Near the Stellate Ganglion Region on Pain and Heart Rate Variability in Patients with Neuropathic Pain

Background

Neuropathic pain associated with sympathetic overactivity can be effectively relieved by light irradiating the region near stellate ganglion (SGI), applied as an alternative to a conventional sympathetic blockade. The clinical effect of SGI on heart rate variability (HRV) and its association with pain outcomes require investigation.

Objective

This study attempted to identify the effects of SGI on pain outcomes and HRV indices and to determine the association between pain and HRV outcomes.

Design

A prospective double-blind, randomized study.

Setting

An outpatient pain medicine clinic.

Subjects and Methods

A total of 44 patients were enrolled and randomized into the experimental group ( n = 22) and control group ( n = 22). The experimental group received 12 sessions (twice weekly) of standard SGI, whereas the control group received the same protocol with sham irradiation. Pain and HRV were measured before and after each irradiation session. All outcome measures used in the first- and second-half treatment courses were analyzed.

Results

Pain and HRV outcome measures of the experimental group significantly improved after SGI when compared with the control group in both courses. Considering time and frequency domains, the changes in HRV in the second-half treatment course exceeded those in the first-half treatment course. Pain was significantly associated with postirradiated HRV indices ( P < 0.001).

Conclusions

Twelve sessions of SGI exerted time-dependent positive effects on pain and sympathovagal imbalance. HRV outcomes, including time and frequency domains, were an independent indicator of the clinical efficiency of SGI for treating pain in patients with neuropathic pain.

Efficacy of Stellate Ganglion Blockade Applied with Light Irradiation: A Systemic Review and Meta-analysis

OBJECTIVE

Stellate ganglion block has mostly been used to relieve symptoms of neuropathic pain; several potential complications have been reported. Noninvasive stellate ganglion block application using light irradiation (SG-LI) can be used as an alternative to conventional injection blockades. Based on the variety of application protocols among previous studies, it was needed to further identify the clinical efficacy of SG-LI in managing neuropathic pain or other disorders associated with sympathetic hyperactivity.

DESIGN

A comprehensive search of online databases was performed to identify experimental or observational studies reporting the efficacy of SG-LI in treating patients with disorders requiring sympatholytic management. The included studies were subjected to a meta-analysis and risk-of-bias assessment.

RESULTS

Twenty-one experimental studies with a Physiotherapy Evidence Database score of 6/10 and 5 observational studies with a Newcastle-Ottawa scale score of 7/9 were included in the analysis. A significant effect on pain relief favoring SG-LI was identified at a standard mean difference (SMD) of -2.05 [95% confidence interval (CI), -2.49 to -1.61; P < 0.00001]. Similar effects favoring SG-LI were found in peripheral blood flow (SMD, 1.26; 95% CI, 0.26-2.25; P = 0.01) and skin temperature (SMD, 1.31; 95% CI, 0.55, 2.08; P = 0.0007).

CONCLUSIONS

Stellate ganglion block application using light irradiation effectively relieves pain of various etiologies and successfully induces a sympatholytic response. Stellate ganglion block application using light irradiation may be a valuable addition to the contemporary pain management armamentarium.

Efficacy of Noninvasive Stellate Ganglion Blockade Performed Using Physical Agent Modalities in Patients with Sympathetic Hyperactivity-Associated Disorders: A Systematic Review and Meta-Analysis

BACKGROUND

Stellate ganglion blockade (SGB) is mainly used to relieve symptoms of neuropathic pain in conditions such as complex regional pain syndrome and has several potential complications. Noninvasive SGB performed using physical agent modalities (PAMs), such as light irradiation and electrical stimulation, can be clinically used as an alternative to conventional invasive SGB. However, its application protocols vary and its clinical efficacy remains controversial. This study investigated the use of noninvasive SGB for managing neuropathic pain or other disorders associated with sympathetic hyperactivity.

MATERIALS AND METHODS

We performed a comprehensive search of the following online databases: Medline, PubMed, Excerpta Medica Database, Cochrane Library Database, Ovid MEDLINE, Europe PubMed Central, EBSCOhost Research Databases, CINAHL, ProQuest Research Library, Physiotherapy Evidence Database, WorldWideScience, BIOSIS, and Google Scholar. We identified and included quasi-randomized or randomized controlled trials reporting the efficacy of SGB performed using therapeutic ultrasound, transcutaneous electrical nerve stimulation, light irradiation using low-level laser therapy, or xenon light or linearly polarized near-infrared light irradiation near or over the stellate ganglion region in treating complex regional pain syndrome or disorders requiring sympatholytic management. The included articles were subjected to a meta-analysis and risk of bias assessment.

RESULTS

Nine randomized and four quasi-randomized controlled trials were included. Eleven trials had good methodological quality with a Physiotherapy Evidence Database (PEDro) score of ≥6, whereas the remaining two trials had a PEDro score of <6. The meta-analysis results revealed that the efficacy of noninvasive SGB on 100-mm visual analog pain score is higher than that of a placebo or active control (weighted mean difference, -21.59 mm; 95% CI, -34.25, -8.94; p = 0.0008).

CONCLUSIONS

Noninvasive SGB performed using PAMs effectively relieves pain of various etiologies, making it a valuable addition to the contemporary pain management armamentarium. However, this evidence is limited by the potential risk of bias.

Effects of xenon irradiation of the stellate ganglion region on fibromyalgia

[Purpose] The aim of the study was to determine the effect of xenon irradiation of the stellate ganglion region on fibromyalgia. [Subjects] The study included 5 men and 22 women (age, 56.4 ± 16.3 years [range, 25–84 years]) who were diagnosed with fibromyalgia according to the modified 2010 criteria of the American College of Rheumatology between July and August 2013. [Methods] Bilateral xenon light irradiation (0.38–1.1 μm) around the stellate ganglion was performed in the supine position by physical therapists using a xenon phototherapy device. We evaluated pain before and after irradiation using the visual analogue scale. [Results] We did not observe a relationship between the change in the visual analogue scale score and duration of fibromyalgia. However, we observed a relationship between the change in the visual analogue scale score and the score for the Japanese version of the Fibromyalgia Impact Questionnaire using the Cochran-Armitage test for trend. [Conclusion] Xenon light irradiation of the stellate ganglion significantly decreased the visual analogue scale score in patients with fibromyalgia having a higher score in the Fibromyalgia Impact Questionnaire, suggesting that a stronger effect could be obtained in patients with more severe fibromyalgia.