A Prospective Clinical Study of Bacteriological Profile and their Antibiotic Susceptibilty Profile in Patients with Chronic Rhinosinusitis: The Recent Scenario in Northern India.

Objectives: 1. To determine the prevailing scenario of the bacteriological profile of patients with CRS, 2. To identify their antibiotic susceptibility profile. Material and methods: The study was conducted on 100 patients in the Department of ENT and Microbiology from December 2020-2022. Patients above the age of 12 years were evaluated. Those who received antibiotics in the last 12 months. and age < 12 years were excluded. Patients were subjected to a detailed history, clinical and radiological examination. After the informed consent of patients and ethical cleareance, samples were taken from the middle meatus area and studied for antibiotics sensitivity: levofloxacin, vancomycin, amikacin, amoxicillin-clavulanic acid and azithromycin. Results: The study was male predominance (71%), with the maximum of patients in the age group 21-30 years (38%). The most common clinical features were nasal obstruction ( 96%) and mucopurulent discharge (100%). The most common isolate was Staphylococcus aureus (45.16%). In Gram-positive, the maximum resistance was shown to azithromycin and amoxicillin-clavulanic acid and the maximum sensitivity to vancomycin, levofloxacin and amikacin. Conclusions: Antibiotic resistance seems to be emerging for azithromycin and amoxicillin-clavulanic acid at a higher rate. MRSA ( 19.35%) maintains a significant presence with associated increased levels of antibiotic resistance.

Insight into the seroepidemiology and dynamics of circulating serotypes of dengue virus over a 4 year period in western Uttar Pradesh, India.

An important public health problem in India is dengue infection, with every year seeing an increase in cases of dengue fever. Dengue affects all individuals irrespective of their gender and age, although the infection rate is higher among males and younger people. Despite low severity in general, dengue virus can cause severe health conditions in some individuals. Genetic characterization of circulating endemic dengue virus (DENV) serotypes plays a significant role in providing epidemiological knowledge and subsequent vaccine development. In the present study, over a 4 year period, we assessed DENV transmission dynamics in major regions of western Uttar Pradesh in North India. ELISA tests were used to diagnose dengue, and PCRs were used to determine the circulating serotype. We found that dengue infection peaks after the rainy season and affects all sexes and ages. A total of 1277 individuals were found positive for dengue; among them, 61.7 % were male and 38.3 % were female. DEN-1 was found in 23.12 %, DEN-2 in 45 %, DEN-3 in 29.06 % and DEN-4 in 1.5 % of the dengue-infected individuals. All four DENV serotypes were circulating in the study area, and DENV serotype-2 (DEN-2) was the most prevalent serotype.

Comparison of Paresthesia Mapping With Anatomic Placement in Burst Spinal Cord Stimulation: Long-Term Results of the Prospective, Multicenter, Randomized, Double-Blind, Crossover CRISP Study.

OBJECTIVES: Spinal cord stimulation (SCS) is an effective therapy for chronic intractable pain. Conventional SCS involves electrode placement based on intraoperative paresthesia mapping; however, newer paradigms like burst may allow for anatomic placement of leads. Here, for the first time, we report the one-year safety and efficacy of burst SCS delivered using a lead placed with conventional, paresthesia mapping, or anatomic placement approach in subjects with chronic low back pain (CLBP). MATERIALS AND METHODS: Subjects with CLBP were implanted with two leads. The first lead was placed to cross the T8/T9 disc and active contacts for this lead were chosen through paresthesia mapping. The second lead was placed at the T9/T10 spinal anatomic landmark. Subjects initially underwent a four-week, double-blinded, crossover trial with a two-week testing period with burst SCS delivered through each lead in a random order. At the end of trial period, subjects expressed their preference for one of the two leads. Subsequently, subjects received burst SCS with the preferred lead and were followed up at 3, 6, and 12 months. Pain intensity (visual analog scale), quality-of-life (EuroQol-5D instrument), and disability (Oswestry Disability Index) were evaluated at baseline and follow-up. RESULTS: Forty-three subjects successfully completed the trial. Twenty-one preferred the paresthesia mapping lead and 21 preferred the anatomic placement lead. Anatomic placement lead was activated in one subject who had no preference. The pain scores (for back and leg) significantly improved from baseline for both lead placement groups at all follow-up time points, with no significant between-group differences. CONCLUSIONS: This study demonstrated that equivalent clinical benefits could be achieved with burst SCS using either paresthesia mapping or anatomic landmark-based approaches for lead placement. Nonparesthesia-based approaches, such as anatomic landmark-based lead placement investigated here, have the potential to simplify implantation of SCS and improve current surgical practice.

Biomarkers of disease severity in vivax malaria.

Severe complications have been observed and established for Plasmodium falciparum as well as P. vivax infections worldwide. Although P. vivax infection is not fully acknowledged as malignant malaria, recently life-threatening complications have been reported to occur in many studies. The recognition of biomarkers with excellent sensitivity and reliability plays a prime role in disease management. Acute inflammatory response and oxidative stress are observed in malaria due to the production of reactive oxygen species. Lipid and protein oxidative injuries are prospective biomarkers for disease severity owing to the damage caused by the parasite. We have tried to find out whether protein carbonylation (PC), lipid peroxidation (LPO) and superoxide dismutase (SOD) could suffice as a biomarker for severe vivax malaria or not. Blood samples were collected from the individuals attending Jawaharlal Nehru Medical College of Aligarh Muslim University during the wet season of malaria transmission. Microscopy and rapid diagnostic kits were used as a tool for malaria diagnosis. A total of 214 subjects were enrolled for the study: 30 febrile controls and 184 subjects with vivax malaria. Protein carbonylation and lipid peroxidation were found to be directly associated with parasite count and total antioxidant status (TAS). Increase in oxidative stress was also observed in severe vivax malaria patients. Levels of uric acid and bilirubin too were raised in complicated cases. Protein carbonylation was found to be a more reliable indicator of vivax malaria severity than lipid peroxidation.

Multicentre, clinical trial of burst spinal cord stimulation for neck and upper limb pain NU-BURST: a trial protocol.

BACKGROUND: Spinal cord stimulation (SCS) is an established therapy for chronic neuropathic pain and most frequently utilised for Failed Back Surgery Syndrome (FBSS). BurstDR™ also known as DeRidder Burst-SCS, a novel waveform, has demonstrated superiority to conventional tonic stimulation of the thoracic spine in FBSS. There are case reports of an improvement in multidimensional pain outcomes using DeRidder Burst-SCS in the cervical spine for chronic neck and cervical radicular pain. The safety and efficacy of cervical DeRidder Burst-SCS stimulation still however remain undetermined. METHODS/DESIGN: This is a prospective, multicentre feasibility trial evaluating the safety and therapeutic efficacy of DeRidder Burst-SCS stimulation for the treatment of chronic intractable neck pain with or without radiation to the arm, shoulder, and upper back. After baseline evaluation, subjects will undergo an SCS trial using the Abbott Invisible Trial system according to standard clinical procedures. During the trial phase, SCS leads will be implanted in the cervical epidural space. At the end of the SCS trial, subjects experiencing at least 50% pain relief will be considered for permanent implant. Pain intensity, medication usage, and other multidimensional pain outcomes will be collected. The timing of these will be at baseline, end of the SCS trial and at 3-, 6-, and 12-month visits. Incidence of adverse events will be collected throughout the study duration. DISCUSSION: The results of this feasibility study will validate the efficacy and safety of DeRidder Burst-SCS stimulation in the cervical spine. The results obtained in this study will potentially be used to generate a level 1 evidence-based study with formal statistical hypotheses testing. TRIAL REGISTRATION: www.clinicaltrials.gov Identifier: NCT03159169.

Investigation on optical temperature sensing behaviour via Ag island-enhanced luminescence doped ß-NaGdF4:Yb3+/Tm3+ films/microfibers.

In this study, silver (Ag) island modified up-conversion nano-particle (NaGdF4:Yb3+/Tm3+) thin films were prepared via electrostatic layer by layer (LBL) and spin coating techniques. The spectroscopic results indicated that adding Ag nanoparticles could significantly enhance the up-conversion emission of NaGdF4:Yb3+/Tm3+ thin films at 452 nm and 476 nm. The maximum enhancement factor of ∼15.6 was reached at 476 nm. Furthermore, we prepared microfibers from upconverting nanoparticles solution, the application of microfibers as active and passive waveguides was analyzed by observing the performance of microfibers with and without Ag under 980 nm excitation of the laser source. The fluorescence intensity ratio (FIR) method was adopted to evaluate microfiber sensitivity. The intensity-based temperature sensitivity of blue emission from a single microfiber containing up-conversion nanomaterials (NaGdF4:Yb3+/Tm3+) and Ag nanoparticles reached up to 0.018 K-1 at 310 K compared to 0.0029 K-1 in Ag-free microfiber. Our results suggest that the novel material can be used to construct new nano-thermometers, useful both in biological experiments as well as industrial research.

Novel Intermittent Dosing Burst Paradigm in Spinal Cord Stimulation.

INTRODUCTION: Intermittent dosing (ID), in which periods of stimulation-on are alternated with periods of stimulation-off, is generally employed using 30 sec ON and 90 sec OFF intervals with burst spinal cord stimulation (SCS). The goal of this study was to evaluate the feasibility of using extended stimulation-off periods in patients with chronic intractable pain. MATERIALS AND METHODS: This prospective, multicenter, feasibility trial evaluated the clinical efficacy of the following ID stimulation-off times: 90, 120, 150, and 360 sec with burst waveform parameters. After a successful trial (≥50% pain relief) using ID stimulation, subjects were titrated with OFF times beginning with 360 sec. Pain, quality of life, disability, and pain catastrophizing were evaluated at one, three, and six months after permanent implant. RESULTS: Fifty subjects completed an SCS trial using ID stimulation settings of 30 sec ON and 90 sec OFF, with 38 (76%) receiving ≥50% pain relief. Pain scores were significantly reduced from baseline at all time points (p < 0.001). Improvements in quality of life, disability, and pain catastrophizing were aligned with pain relief outcomes; 45.8% of the subjects that completed the six-month follow-up visit used an OFF period of 360 seconds. CONCLUSIONS: ID burst SCS effectively relieved pain for six months. The largest group of subjects used IDB settings of 30 sec ON and 360 sec OFF. These findings present intriguing implications for the optimal "dose" of electricity in SCS and may offer many advantages such as optimizing the therapeutic window, extending battery life, reducing recharge burden and, potentially, mitigating therapy habituation or tolerance.

A micro-epidemiological report on the unstable transmission of malaria in Aligarh, India.

India contributes approximately 70% to the malaria burden of Southeast Asia. The transmission of disease in the country is generally hypoendemic, seasonal and unstable. Most researchers focus upon the hyperendemic malarious regions with stable malaria transmission. There is paucity of data regarding malaria transmission in hypoendemic regions, here we are presenting an epidemiological picture of clinical manifestations through a hospital-based survey in Aligarh, India, during 2016-18. Two thousand sixty-eight patients were diagnosed with malaria infection in Jawaharlal Nehru Medical College and Hospital (JNMCH), out of which 1104 were enrolled for clinical analysis. Ninety per cent of the cases were reported during July-November, and the rest in the dry season. A progressive increase in the prevalence rate was observed during the study period, i.e. 4.8, 7.57 and 8.7% in 2016, 2017 and 2018, respectively. Of the total cases, 75.77% had vivax malaria, while rest suffered from falciparum malaria. The risk of disease was significantly higher in the age group 0-15 years compared to all other age groups (p < .0001). The infection rate was higher in males (61%) compared to females (39%) p < .0001. Overall 8.6% of the patients had severe malaria who fulfilled the WHO criteria. The increasing rate of malaria infection during the study period and a considerable no. of severe vivax malaria cases warrant an efficient disease monitoring system, pointing towards the need to carry out micro-epidemiological studies in order to estimate the real burden of malaria in the country.

Comparison of Paresthesia Mapping to Anatomical Placement in Burst Spinal Cord Stimulation: Initial Trial Results of the Prospective, Multicenter, Randomized, Double-Blinded, Crossover, CRISP Study.

INTRODUCTION: In this prospective, multicenter, double-blinded, randomized, crossover study, we compared the therapeutic efficacy of burst SCS delivered using a lead implanted with the paresthesia mapping approach to a lead implanted with an anatomic placement approach. MATERIALS AND METHODS: Subjects with chronic low back pain were implanted with two leads, one using paresthesia-mapping approach (PM) and the second using anatomical placement procedure (AP). Stimulation contacts were chosen using the standard intraoperative paresthesia-testing procedure for the paresthesia-mapped lead or an activated bipole overlapping the T9-T10 junction for the anatomical lead. Amplitude for either lead was selected such that no sensory percepts were generated. Subjects were assessed at baseline and after a trial period during which they tested each lead for two weeks in random order. Eligible subjects had the option to receive permanent implants using their preferred AP or PM approach at end-of-trial. RESULTS: Of the 53 subjects who completed both trial periods, 43 (81.1%) experienced at least 50% back pain relief with at least one lead. Nearly half of these (20; 46.5%) were profound responders who experienced at least 80% back pain relief with either leads. Primary and secondary outcomes, at the end of trial, showed significant improvements for both AP and PM leads from baseline yet were not significantly different from each other. DISCUSSION: The trial results of this study suggest that similar clinical outcomes can be achieved in burst SCS when performing lead placement either using paresthesia mapping or anatomical placement with imaging references.

A Prospective Study of Dorsal Root Ganglion Stimulation for Non-Operated Discogenic Low Back Pain.

INTRODUCTION: Disruptions of lumbar intervertebral discs may lead to severe discogenic low back pain (LBP). Severe pain has a deleterious effect on physical function and quality of life. Spinal cord stimulation (SCS) is a robust treatment for many neuropathic pain conditions. New innovations may be well-suited to treat neuropathic chronic LBP, including discogenic pain. The aim of this prospective study was to determine the effect of dorsal root ganglion (DRG) stimulation for a well-selected group of patients with discogenic LBP with no history of previous back surgeries. METHODS: Twenty subjects with confirmed discogenic LBP and no prior history of back surgery underwent trials of DRG stimulation and, if successful with at least 50% pain reduction, were permanently implanted. Subjects rated their pain, disability, quality of life, and mood at baseline, and 14 subjects were followed through 12 months of treatment. RESULTS: Treatment with DRG stimulation reduced LBP ratings (68.3% reduction), from mean 7.20 ± 1.3 at baseline to 2.29 ± 2.1 after 12 months (p = < 0.001). Oswestry ratings of disability significantly decreased (p = < 0.001) from 42.09 ± 12.9 at baseline to 21.54 ± 16.4 after six months of treatment and to 20.1 ± 16.6 after 12 months. The average quality of life EQ-5D index score at baseline was 0.61 ± 0.12 and 0.84 ± 0.13 after 12 months. DISCUSSION: DRG stimulation treatment for discogenic LBP improved the level of pain, function, and quality of life. Further research is necessary into efficacy of DRG stimulation in patients with chronic discogenic LBP and to determine the place of SCS in the treatment algorithm.

Paresthesia-Free Dorsal Root Ganglion Stimulation: An ACCURATE Study Sub-Analysis.

INTRODUCTION: ACCURATE, a randomized controlled trial comparing dorsal root ganglion (DRG) stimulation to spinal cord stimulation, showed that DRG stimulation is a safe and effective therapy in individuals with lower extremity chronic pain due to complex regional pain syndrome (CRPS) type I or II. Investigators noted that DRG stimulation programming could be adjusted to minimize, or eliminate, the feeling of paresthesia while maintaining adequate pain relief. The present study explores treatment outcomes for DRG subjects who were paresthesia-free vs. those who experienced the sensation of paresthesia, as well as the factors that predicted paresthesia-free analgesia. METHODS: A retrospective analysis of therapy outcomes was conducted for 61 subjects in the ACCURATE study who received a permanent DRG neurostimulator. Outcomes of subjects who were paresthesia-free were compared to those who experienced paresthesia-present therapy at 1, 3, 6, 9, and 12-month follow-ups. Predictor variables for the presence or absence of paresthesias with DRG stimulation were also explored. RESULTS: The percentage of subjects with paresthesia-free pain relief increased from 16.4% at 1-month to 38.3% at 12-months. Paresthesia-free subjects generally had similar or better outcomes for pain severity, pain interference, quality of life, and mood state as subjects with paresthesia-present stimulation. Factors that increased the odds of a subject feeling paresthesia were higher stimulation amplitudes and frequencies, number of implanted leads, and younger age. CONCLUSIONS: Some DRG subjects achieved effective paresthesia-free analgesia in the ACCURATE trial. This supports the observation that paresthesia is not synonymous with pain relief or required for optimal analgesia with DRG stimulation.

Therapy Habituation at 12 Months: Spinal Cord Stimulation Versus Dorsal Root Ganglion Stimulation for Complex Regional Pain Syndrome Type I and II.

The ACCURATE randomized, controlled trial compared outcomes of dorsal root ganglion (DRG) stimulation versus tonic spinal cord stimulation (SCS) in 152 subjects with chronic lower extremity pain due to complex regional pain syndrome (CRPS) type I or II. This ACCURATE substudy was designed to evaluate whether therapy habituation occurs with DRG stimulation as compared to SCS through 12-months. A modified intention-to-treat analysis was performed to assess percentage pain relief (PPR) and responder rates at follow-up visits (end-of-trial, 1, 3, 6, 9, 12-months postpermanent implant) for all subjects that completed trial stimulation (DRG:N = 73, SCS:N = 72). For both groups, mean PPR was significantly greater at end-of-trial (DRG = 82.2%, SCS =0 77.0%) than all other follow-ups. Following permanent DRG system implantation, none of the time points were significantly different from one another in PPR (range = 69.3-73.9%). For the SCS group, PPR at 9-months (58.3%) and 12-months (57.9%) was significantly less than at 1-month (66.9%). The responder rate also decreased for the SCS group from 1-month (68.1%) to 12-months (61.1%). After stratifying by diagnosis, it was found that only the CRPS-I population had diminishing pain relief with SCS. DRG stimulation resulted in more stable pain relief through 12-months, while tonic SCS demonstrated therapy habituation at 9- and 12-months. Trial Registration: The ACCURATE study was registered at ClinicalTrials.gov with Identifier NCT01923285. PERSPECTIVE: This article reports on an ACCURATE substudy, which found that long-term therapy habituation occurred at 12-months with SCS, but not DRG stimulation, in patients with CRPS. The underlying mechanisms of action for these results remain unclear, although several lines of inquiry are proposed.

Correction to: Polymer Microfibers Incorporated with Silver Nanoparticles: a New Platform for Optical Sensing.

Please note that following publication of the original article [1], these three sentences have been removed from the Background section of the article.

Polymer Microfibers Incorporated with Silver Nanoparticles: a New Platform for Optical Sensing.

The enhanced sensitivity of up-conversion luminescence is imperative for the application of up-conversion nanoparticles (UCNPs). In this study, microfibers were fabricated after co-doping UCNPs with polymethylmethacrylate (PMMA) and silver (Ag) solutions. Transmission losses and sensitivities of UCNPs (tetrogonal-LiYF4:Yb3+/Er3+) in the presence and absence of Ag were investigated. Sensitivity of up-conversion luminescence with Ag (LiYF4:Yb3+/Er3+/Ag) is 0.0095 K-1 and reduced to (LiYF4:Yb3+/Er3+) 0.0065 K-1 without Ag at 303 K under laser source (980 nm). The UCNP microfibers with Ag showed lower transmission losses and higher sensitivity than without Ag and could serve as promising candidate for optical applications. This is the first observation of Ag-doped microfiber via facile method.

Differential status and significance of non-enzymatic antioxidants (reactive oxygen species scavengers) in malaria and dengue patients.

An imbalance in oxidants and antioxidants is observed during malaria and dengue infections which is associated with the production of reactive oxygen species (ROS) via haem degradation or immune activation, a contributing factor for disease pathogenesis. The levels of non-enzymatic antioxidants and total antioxidant status (TAS) in malaria and dengue patients were analysed and compared with healthy controls. Particular attention was paid to elevated levels of total bilirubin (TB) and uric acid (UA) during disease progression and haemolysis and noticed a significant increase in dengue patients (dengue>Pf>Pv>control). A highly significant difference was also observed between dengue and Pf patients (p < 0.0001) for these parameters. Glutathione levels were comparable in dengue and falciparum malaria but were significantly higher than that of vivax malaria patients. Ascorbate levels were significantly depleted in all the patient groups (p < 0.0001) and a negative correlation was established for TAS and ascorbate levels in dengue patients (r=-0.32). A good positive correlation was observed between TAS-UA and TAS-TB levels. Thus, these findings suggest that severe haemolysis, renal failure, and liver dysfunction have higher prominence in dengue patients during the simultaneous outbreak of the two arthropod-borne diseases. A differential status of non-enzymatic antioxidants was also observed during the different stages of dengue and malaria.

Comparison of Paresthesia Coverage of Patient's Pain: Dorsal Root Ganglion vs. Spinal Cord Stimulation. An ACCURATE Study Sub-Analysis.

OBJECTIVES: This was a sub-analysis of the ACCURATE clinical trial that evaluated the accuracy and necessity of targeting paresthesia coverage of painful areas with dorsal root ganglion (DRG) stimulation vs. tonic spinal cord stimulation (SCS). MATERIALS AND METHODS: On diagrams of the torso and lower limbs, subjects marked where they felt pain at baseline and paresthesias at three months postimplant. Seventy-five subjects (41 DRG and 34 SCS) with diagrams of sufficient quality were scanned, digitized, and included in this analysis. Subject completed diagrams were digitized and superimposed with a grid of 1398 squares. Quantification of the percentage of bodily areas affected by pain and stimulation induced paresthesias was performed. RESULTS: The percent of painful areas covered by paresthesia was significantly lower for DRG subjects than for SCS subjects (13% vs. 28% of the painful regions, p < 0.05), possibly because significantly more DRG subjects felt no paresthesia during stimulation when compared to SCS subjects (13/41 DRG vs. 3/34 SCS) (p < 0.05). The amount of paresthesia produced outside the painful areas (unrequired paresthesia) was significantly lower in DRG subjects than that of SCS subjects. On average, the percent of unrequired paresthesia was only 20% of the subjects' total painful body surface area in the DRG group compared to 210% in the SCS group (p < 0.01). CONCLUSIONS: The results of this ACCURATE study sub-analysis show that DRG stimulation produces paresthesias, on average, that are less frequent, less intense, with a smaller footprint on the body and less dependent on positional changes.

Early US Experience With Stimulation of the Dorsal Root Ganglia for the Treatment of Peripheral Neuropathy in the Lower Extremities: A Multicenter Retrospective Case Series.

BACKGROUND: Peripheral neuropathy is a chronic pain disorder involving physical, chemical, or metabolic damage to peripheral nerves. Its pain can be intense and disabling. Dorsal root ganglion (DRG) stimulation is an effective treatment for neuropathic pain, including cases with the limited regional distributions that often characterize peripheral neuropathy. METHODS: A retrospective analysis was completed. Patients were included on the basis of having chronic intractable peripheral neuropathy of the legs and/or feet and responding successfully to a trial of DRG stimulation with leads at L4-S1. Visual analog scale pain scores and pain medication usage were collected at the baseline visit and after six weeks of treatment. Eight consecutive patients across two study centers were included (7 male, 1 female; mean age: 64.8 ± 10.2 years). Six cases of neuropathy were bilateral and two were unilateral. One patient presented with chronic radiculopathy, two patients had neuropathy associated with diabetes, and five patients had neuropathy not associated with a diabetes history. RESULTS: The pain was rated 7.38 ± 0.74 at baseline and decreased to 1.50 ± 1.31 at the 6-week follow-up, a reduction of 79.5 ± 18.8%. For individual patients, pain relief ranged from 42.86% to 100.00%; two patients experienced complete elimination of pain while seven of the eight patients experienced greater than 50% pain relief. In addition, three patients significantly decreased their pain medication use and four were able to discontinue their medications entirely. CONCLUSION: This small multicenter retrospective case series provides preliminary evidence that the painful symptoms of general peripheral neuropathy in the lower extremities, as well as associated pain medication usage, can be effectively managed by DRG stimulation at the L4-S1 spinal level. Importantly, this treatment appears efficacious for peripheral neuropathy.

Prospective Cohort Analysis of DRG Stimulation for Failed Back Surgery Syndrome Pain Following Lumbar Discectomy.

INTRODUCTION: Surgical lumbar discectomy is a commonly performed routine spinal procedure that is usually undertaken to alleviate lumbar radicular symptoms caused by a herniated intervertebral disc. Surgical lumbar discectomy can also lead to chronic postsurgical leg and/or back pain (failed back surgery syndrome [FBSS]), a condition that can be refractory to conventional medical management. Early clinical results on the use of dorsal root ganglion (DRG) stimulation for FBSS have supported the use of this treatment alternative. METHODS: A multicenter, single-arm, observational cohort study enrolled patients who had chronic pain following surgical lumbar discectomy, had failed conservative treatments, and reported pain intensity of at least 6 out of 10 in the primary region of pain. Data were collected on pain, quality of life, disability, and mood at baseline and through 12 months. RESULTS: Thirteen patients underwent a trial of DRG stimulation; 11 (84.6%; 95% confidence interval = 57.8% to 95.7%) had good outcomes and underwent permanent device placement. Pain was reduced from a score of 8.64 (±0.92) at baseline to 2.40 (±2.38; n = 9) after 12 months of treatment, a 72.05% average reduction (P < 0.001). Similar improvements were observed across the secondary clinical measures, and safety data were in line with published rates. DISCUSSION: These results suggest that DRG stimulation induces pain relief in subjects diagnosed with FBSS. These reductions in pain were also associated with improvements in quality of life and disability. Additional prospective studies are warranted to further investigate this potential application of DRG stimulation, as well as to optimize patient selection, lead placement, and programming strategies.

A Review of Spinal and Peripheral Neuromodulation and Neuroinflammation: Lessons Learned Thus Far and Future Prospects of Biotype Development.

BACKGROUND: There is increasing literature evidence both clinically and experimentally on the existence of potent, adaptive interactions between the central and peripheral aspects of the neuroimmune system in the genesis and maintenance of chronic neuropathic extremity pain and nociceptive back pain. The neuroinflammatory pathways are modulated by the interaction of pro- and anti-inflammatory cytokines and chemokines, which are released by peripheral immune system-derived cell species (macrophages and leukocytes). This review examines the possible impact of spinal and peripheral neurostimulation on the inflammatory response in the context of acute and chronic pain pathologies of different origin. STUDY DESIGN: A narrative review of preclinical and clinical studies addressed to the spinal cord and peripheral nerve stimulation and neuroinflammation. METHODS: Available literature was reviewed on neurostimulation technologies and both acute and chronic low-grade inflammation to identify primary outcome measures and to provide an overview of postulated mechanisms of action of neurostimulation on host inflammatory responses. Data sources included relevant literature identified through searches of PubMed, MEDLINE/OVID, SCOPUS, and manual searches of the bibliographies of known primary and review articles. RESULTS: A comprehensive review of the literature indicates an alternate or synergistic mechanism of action of neurostimulation, beyond modulating somatosensory pain pathways, in modifying inflammatory response associated with chronic pain, by promoting a systemic anti-inflammatory state with upregulation of anti-inflammatory mediators. CONCLUSIONS: These preliminary findings may have important implications on the potential applications of neurostimulation as an anti-inflammatory therapy and the role of molecular profiling as a preimplant screening modality and post-implant outcome validation. Thus, future targeted clinical and experimental research is highly warranted in this particular novel field of neuromodulation.

Burst Spinal Cord Stimulation: Review of Preclinical Studies and Comments on Clinical Outcomes.

BACKGROUND: Burst spinal cord stimulation (SCS) technology uses a novel waveform that consists of closely packed high-frequency electrical impulses followed by a quiescent period. Within the growing field of neuromodulation, burst stimulation is unique in that it mimics the natural burst firing of the nervous system, in particular the thalamo-cingulate rhythmicity, resulting in modulation of the affective and attentional components of pain processing (e.g., medial thalamic pathways). STUDY DESIGN: A review of preclinical and clinical studies regarding burst SCS for various chronic pain states. METHODS: Available literature was reviewed on burst stimulation technology. Data sources included relevant literature identified through searches of PubMed, MEDLINE/OVID, SCOPUS, and manual searches of the bibliographies of known primary and review articles. OUTCOME MEASURES: The primary outcome measure was to understand the mechanisms of action with regards to burst stimulation and to review clinical data on the indications of burst SCS for various chronic pain states. RESULTS: We present both mechanisms of action and review uses of burst stimulation for various pain states. CONCLUSIONS: Burst stimulation offers a novel pain reduction tool with the absence of uncomfortable paresthesia for failed back surgery syndrome, diabetic neuropathic pain, and anesthesia dolorosa. Preclinical models have emphasized that the potential mechanisms for burst therapy could be related to neural coding algorithms that mimic the natural nervous system firing patterns, resulting in effects on both the medial and lateral pain pathways. Other mechanisms include frequency dependent opioid release, modulation of the pain gate, and activation of electrical and chemical synapses.