Pulsed Radiofrequency Procedure Research Articles

Peripheral nerve pulsed radiofrequency for trigeminal neuralgia treatment: Is it an effective method?

Trigeminal neuralgia is a paroxysmal and shock-like pain in the trigeminal nerve area. Various treatment options have been used for trigeminal neuralgia such as medical treatment, interventional procedures, and surgical operations. Pulsed radiofrequency (PRF) is a minimally invasive percutaneous technique which seems to be safer and easier to perform. This retrospective study aims to evaluate the analgesic effect, duration of efficacy, and side effects of PRF procedures in the peripheral branches of the trigeminal nerve. The data of the patients with trigeminal neuralgia who were followed up in our hospital's algology clinic from 2016 to 2018 were reviewed retrospectively. Patients aged between 18 and 70 who did not respond to medical treatment or could not use medication due to side effects were treated with PRF procedure for peripheral branches of trigeminal nerve that was selected for this study. Demographic profile, clinical presentation, pain intensity, duration of efficacy, and complications were evaluated from their files. Twenty-one patients who underwent ultrasonography guided PRF procedures were included the study. Mean visual analog scale value of the patients was found to have decreased from 9.25±0.63 to 1.55±0.88 at the end of the 1st month (p<0.001). The painless period for the patients lasted up to 12 (9-21) months and no complications occurred. PRF procedure seems to be an effective and safe method in patients who respond to block of the peripheral branches of the trigeminal nerve.

Management of Postherpetic Neuralgia with Pulsed Radiofrequency Dorsal Root Ganglion: A Case Report

Introduction: Radiofrequency therapy is a minimally invasive procedure that has been used for about three decades to treat various chronic pain, such as postherpetic pain. This case study aims to describe the use of PRF in postherpetic neuralgia.&#x0D; Case presentation: A woman, 71 years old, came with complaints of right low back pain. Pain that is felt like burning, burning, sometimes pain feels like being stabbed, electrocuted, throbbing, and the pain will increase if the area of the skin is touched by a cloth. The pain began to be felt approximately 11 years ago. Physical examination shows vital signs; blood pressure 140/75 mmHg, pulse 76x/minute, respiratory rate 20x/minute, oxygen saturation 97%, temperature 36,5oC, numeric rating scale (NRS) 8-9/10. On examination of the right lumbar region, hypopigmented lesions appeared around the right waist at L3, L4, and L5 levels. No hyperemia and edema were found, and no obvious sensory loss. Assessment of pain score according to the Socrates method 8/10, S-LANSS score (self-report Leeds assessment of neuropathic symptoms and signs) 16. The patient has been diagnosed with postherpetic neuralgia. Patients were treated with a pulsed radiofrequency (PRF) procedure on the dorsal root ganglion (DRG). Pulsed radiofrequency was performed on the dorsal root ganglion at L1, L2, L3, and L4 levels.&#x0D; Concussion: The pulsed radiofrequency procedure on the dorsal root ganglion is a minimally invasive procedure that is effective and safe in treating postherpetic neuralgia pain. The use of imaging guidance in this procedure can improve the accuracy of needle tip placement and prevent side effects and complications.

Effectiveness of pulsed radiofrequency on the medial cervical branches for cervical facet joint pain

BACKGROUNDCervical facet joint pain (CFP) is one of the most common causes of neck pain and headache. Persistent CFP deteriorates the quality of life of patients and reduces their productivity at work.AIMTo investigate the effectiveness of pulsed radiofrequency (PRF) stimulation of cervical medial branches in patients with chronic CFP. METHODSWe retrospectively included 21 consecutive patients (age = 50.9 ± 15.3 years, range 26-79 years; male: female = 8:13; pain duration = 7.7 ± 5.0 mo) with chronic CFP, defined as ≥ 4 on the numeric rating scale (NRS). We performed PRF stimulation on the cervical medial branches. The outcomes of the PRF procedure were evaluated by comparing the NRS scores for CFP before treatment and 1 and 3 mo after treatment. Successful pain relief was defined as a ≥ 50% reduction in the NRS score at 3 mo when compared with the pretreatment NRS score. RESULTSNo patient had immediate or late adverse effects following PRF. The average NRS score for CFP decreased from 5.3 ± 1.1 at pre-treatment to 2.4 ± 0.6 at the 1 mo follow-up, and 3.1 ± 1.1 at the 3 mo follow-up. Compared to the NRS scores before PRF stimulation, those at 1 and 3 mo after PRF stimulation had significantly decreased. Eleven of the 21 patients (52.4%) reported successful pain relief 3 mo after the PRF procedure. PRF stimulation on cervical medial branches may be a useful therapeutic option to control chronic CFP.CONCLUSIONPRF stimulation of the cervical medial branches may be used as an alternative treatment method in patients with CFP. PRF can effectively alleviate CFP, and is safe to perform.

Clinical Radiofrequency Ablation Outcomes of Combined Sensory Nerve Branch and Dorsal Entry Root Zone Complex Lesions for Sacroiliac Joint Complex Pain.

Chronic lower back pain (LBP) with or without leg pain (LP) is the most commonly reported anatomical site of pain among Canadian adults with chronic pain. A common cause for LBP and LP arises from dysfunction of the sacroiliac joint (SIJ) complex. When conventional medical management or rehabilitative efforts for SIJ-related LBP and LP fail to provide analgesia, pulsed radiofrequency (PRF) and/or radiofrequency ablation (RFA) of the dorsal entry root zone complex lesions (DREZC) and/or their more peripheral branches can also be a suitable means for treatment. Both PRF and RFA are interventional techniques that utilize heat to attenuate or ablate transmission of painful signals, respectively. The purpose of this chart review is to explore the clinical outcomes of patients experiencing SIJ-related pain who have undergone procedures with combined sensory nerve branch RFA and DREZC PRF lesions targeting the SIJ complex. Following institutional review board approval, a retrospective chart review was performed from June 2018 to February 2021 for patients with LBP and/or LP refractory to physical rehabilitative efforts and medical management that underwent combined PRF and RF treatments for a diagnosis of SIJ complex pain. RF and PRF procedures were anatomically guided with the addition of sensory stimulation to ensure appropriate needle placement. Charts were reviewed for percentage of analgesia at final follow-up, duration of effect, degree of analgesia, patients' functional improvements, and changes in medication use patterns. Data was reviewed from 180 patients with LBP or LP who underwent combined PRF and RF treatments for a diagnosis of SIJ complex pain. The group consisted of 69 men and 111 women with a mean age of 59years. All patients had lesions to their dorsal roots and/or branches (lumbar medial and sacral lateral), as determined using their pain profile as well as sensory stimulation. In the sample of 180 patients a total of 276 SIJs were treated over the period of data collection. Overall, 85.0% (n = 234) of procedures were considered successful with more than 50% analgesic relief at final follow-up. Of 234 successful outcomes, 110 reported ongoing analgesia (mean = 80.3% pain relief, SD ± 18.0) on the last date of follow up (mean = 53.2days, SD ± 41.8) prior to being lost to follow-up. For patients not lost to follow-up, the mean amount of analgesia was reported to be 83.9% with an average duration of 86.3days. Among all treatments, 6.9% (n = 19) provided no analgesic effect. Among the successful procedure outcomes, 54.4% (n = 150) reported increased activity/mobility, 24.3% (n = 67) reported improved sleep, 49.3% (n = 136) reported improved mood, and 11.6% (n = 32) reported decreased medication usage. Nine patients reported complications following the procedure. Complications included transient soreness, bruising, tenderness, myofascial pain, and two mild vagal responses without lasting sequelae. This review suggests that combined sensory nerve branch RFA and DREZC PRF lesions targeting the SIJ complex is a suitable intervention to treat SIJ-related LBP and/or LP refractory to physical rehabilitative efforts and medical management. Approximately 85% of these cases were successfully treated with the majority of patients report lasting analgesic effects with minimal complications, supporting the use of sensory stimulation-guided combined RF and PRF lesions for treatment of refractory SIJ complex pain.

Pulsed Radiofrequency Increases Nestin and Matrix Metalloproteinase-2 Expression in Porcine Lumbar Dorsal Root Ganglion.

BackgroundPulsed radiofrequency (PRF) has been used for the treatment of chronic lumbar radicular pain and other chronic pain states. The dorsal root ganglion (DRG) consists of primary afferent somatic and visceral nerve cell bodies that transduce sensory signals from the periphery to the central part of the nervous system. It is a very important part of acute nociception, as well as the development and maintenance of chronic pain.MethodsA total of seven domestic pigs were investigated. All pigs underwent a PRF procedure while under general anesthesia and with X-ray imaging. Four lumbar DRGs were randomly treated. We used the opposite side of the DRGs as controls. The lumbar region of the spine was placed in 10% formaldehyde for one month. After this fixation, DRG samples were prepared for slide analysis.ResultsNestin (Nes, code-Nr. AB 5968, dilution 1:250, rabbit, Abcam, United Kingdom) and matrix metallopeptidase 2 (MMP-2, code-Nr. DUB 03, dilution 1:100, goat) expressions were detected by immunohistochemical staining. The cell numbers with Nes (28.4 ± 3.3 vs. 16.1 ± 3.4; P < 0.05) and MMP-2 (26.2 ± 3.2 vs. 14.1 ± 2.3; P < 0.05) expressions were larger on the PRF side compared to the control side. The glial cells in the spinal ganglia on both sides showed immunoreactivity.ConclusionsThe increase of MMP-2-containing gangliocytes one month after PRF procedures highlights active neural cell proliferation. Increased Nes factor expression in spinal gangliocytes of the lumbar region indicates neural remodeling and regeneration.

Pulsed radiofrequency treatment of the dorsal root ganglion in patients with chronic neuropathic pain: A narrative review

Background: Chronic neuropathic pain (CNP) is a complex condition that has profound impacts on quality of life. Pulsed radiofrequency (PRF) on the dorsal root ganglia (DRGs) is a novel treatment that has shown clinical efficacy in pain relief, however, its mechanism remains unknown. Objectives: The objective of this review is to synthesize the literature on inflammatory markers and clinical pain outcomes in CNP patients treated with PRF. Study Design: A narrative review was conducted. Setting: Eligibility criteria included human trials on adults diagnosed with CNP. Monopolar and bipolar PRF treatments on the DRG were included. Methods: Four peer reviewed electronic databases (Medline, EMBASE, PubMed, and Cochrane) were systematically searched for studies on PRF on the DRG to treat CNP. The primary outcome measures included pain scores and cerebrospinal fluid samples taken pre- and posttreatment measuring inflammatory markers. Results: Thirty-three articles were identified in the database searches. Titles, abstracts, and full-text articles were evaluated, and eight articles met the inclusion criteria. The study designs included five randomized-controlled trials and three quasi-experimental studies. Patients: There were 311 patients pooled with an age range of 35–76 years. Types of CNP included chronic radicular pain, postmastectomy pain syndrome, chronic lumbosacral pain, and postherpetic neuralgia. Intervention: Treatments in included studies included monopolar and bipolar PRF stimulation ranging from 120 s at 2 Hz to 360 s with 5 Hz pulses. Measurement: The main findings revealed that PRF treatment provided significant pain relief (P < 0.05), with the greatest pain reduction at 3 months. Pro-inflammatory markers were found to decrease, whereas anti-inflammatory markers increased post-PRF intervention. Limitations: There were differing PRF procedure standards, and it is uncertain whether a higher frequency or duration is correlated with better outcomes. Studies had small sample sizes increasing the margin of error. Longer duration randomized-controlled trials are needed to understand the optimal therapeutic duration using PRF.

Effects of intralesional pulsed radiofrequency treatment on pain in patients with calcaneal spur: results of 460 patients

BackgroundThis study aimed to investigate the efficacy of intralesional pulsed radiofrequency (RF) in the treatment of calcaneal spur and the results of patients who underwent single and double sessions of RF treatment.MethodsThe population of this retrospective study consisted of 460 patients who were diagnosed with calcaneal spur with clinical examination and direct radiography. The Wong-Baker Faces Pain Rating Scale and The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score were used to determine the pain status and functional capacities of the patients. Posttreatment evaluation was carried out on average in the 6th week.ResultsThe study involved 460 patients, 76.9% of whom were female, with the average age of 50.8 ± 10.9 years in total. Of the patients 43% was given RF therapy in a single session, and 57% of them in double sessions. After the RF procedure, the number of patients whose pain decreased according to both AOFAS and Wong-Baker pain scoring systems increased statistically significantly (p < 0.001). There was a statistically significant increase in the AOFAS-pain scores and the total AOFAS scores and a significant decrease in the Wong Baker-pain scale after treatment. However, there was no significant change in treatment success with respect to the number of RF sessions. Although not statistically significant, the differences in the AOFAS-pain scores and in the total AOFAS scores were found to be higher in patients who underwent single session RF, while the difference in the Wong Baker-pain ranking was higher in patients who received double sessions RF.ConclusionIntralesional pulsed RF procedure can be preferred as a relatively less invasive method that does not have any serious complications in patients with persistent calcaneal spurs who do not respond to the use of oral anti-inflammatory drugs and shoe insoles, nor corticosteroid injection to the lesion area.

Neuromodulation in Odontogenic Pain: A Case Series

BACKGROUND: Teeth and other intraoral structures are the most frequent sources of orofacial pain. Pulsed radiofrequency (PRF) is a treatment where an intermittent electrical pulse is applied to a painful nerve. CASE REPORT: Twelve patients who reported odontogenic were enrolled. After a positive anesthetic block test at the affected nerve, a PRF procedure was performed. After the procedure, patients were asked to report the degree of tolerability of the procedure, and each patient was reevaluated after one and 6 months in terms of overall satisfaction, reduction of pain, and number of attacks. A total of 18 procedures were performed over 12 patients; 8 patients reported significant clinical improvement . Maximum and mean self-reported pain ratings decreased significantly at both the one- and 6-month follow-ups. CONCLUSION: The use of PRF in treating odontogenic pain appears to show promising results: it is feasible, safe, and associated with little discomfort for the patient. KEY WORDS: Odontogenic pain, neuromodulation, pulsed radiofrequency, interventional pain procedure

Therapeutic Efficacy of Ultrasound-Guided High-Voltage Long-Duration Pulsed Radiofrequency for Pudendal Neuralgia.

Pudendal neuralgia (PN) is a complex disease with various clinical characteristics, and there is no treatment showing definite effectiveness. This study is aimed at evaluating the clinical efficacy of ultrasound-guided high-voltage long-duration pulsed radiofrequency (PRF) for PN. Two cadavers (one male, one female) were dissected to provide evidence for localization of the pudendal nerve. Patients diagnosed as PN who failed or were intolerant in regular medication were screened for diagnostic local anesthesia block of the pudendal nerve before recruitment. Twenty PN patients were enrolled in this study. In the PRF procedure, the needle tip was inserted medially into the internal pudendal artery under ultrasound guidance. The position of the PRF needle tip was then adjusted by the response of the pudendal nerve to the electrical stimulation within the pudendal area (42°C, a series of 2 Hz, and 20 ms width pulses that lasted for 900 s). Alleviation of pain was assessed by the visual analogue scale (VAS) and sitting time pretreatment and on 7 d, 14 d, 1 m, 2 m, 3 m, and 6 m posttreatment in outpatient follow-up or by telephone interview. Two patients were lost due to intervention-irrelevant reasons. Patients showed significantly decreased VAS scores on 7 d after RFP, compared with pretreatment status (7.0 ± 0.9 vs. 3.2 ± 1.7, P < 0.001). The efficacy remained steady till the end of 6 months, with a final remission rate of 88.9%. Sitting time also significantly lengthened following PRF (7 d, 14 d, 1 m, 2 m, 3 m, and 6 m vs. pretreatment, all P < 0.05). Only short-term ipsilateral involuntary convulsion of the lower extremity was reported in one patient, who recovered within 12 h. Six patients were treated with nonsteroidal drugs for a short time. All patients stopped taking medication finally. In conclusion, the ultrasound-guided high-voltage long-duration PRF approach not only reduced the pelvic pain caused by PN but also improved the quality of life by extending sitting time without nerve injury.

Pulsed Radiofrequency of the Trigeminal Ganglion for Treating Postherpetic Neuralgia of the Ophthalmic Branch.

Postherpetic neuralgia (PHN) is a painful, long-lasting condition as a consequence of nerve damage resulting from a herpes zoster infection. Although there are many different treatments available to reduce pain duration and severity, PHN is often refractory to them and no single therapy shows an effective cure for all cases of PHN, especially for those involving the ophthalmic branch of the trigeminal nerve. Pulsed radiofrequency (PRF) is a minimally invasive procedure for pain treatment that has been practiced over the past decade. However, its clinical efficacy and safety for treating PHN involving the ophthalmic branch of the trigeminal nerve have not been evaluated. Objective. This study aimed to evaluate the efficacy and safety of PRF for treating PHN involving the ophthalmic branch of the trigeminal ganglion. Study Design. An observational study. Setting. All patients received PRF of the ophthalmic branch of the trigeminal nerve, pain intensity was assessed by a visual analogue scale (VAS), and complications before and after PRF stimulation were noted. Methods. Thirty-two patients with PHN of the ophthalmic branch were treated by PRF of the ophthalmic branch with controlled temperature at 42°C for 8 min. Pain relief, corneal reflex, sleep quality, and satisfaction were assessed for all patients. Results. Thirty out of 32 patients (93.75%) reported significant pain reduction after PRF treatment. Twenty-eight of them (87.5%) were satisfied with their sleep and obtained a pain score lower than 3 following the procedure. Only two patients had a recurrence of the severe burning pain and returned to the hospital for other medical therapies 2 weeks after the PRF procedure. No patient lost the corneal reflex. Limitations. This study is an observational study and a nonprospective trial with a short-term follow-up period. Conclusion. PRF of the trigeminal ganglion of the ophthalmic branch can significantly reduce pain sensation and improve sleep quality and satisfaction for PHN of the ophthalmic branch.

The Effect of Pulsed Radiofrequency on Radicular Pain in Lumbal Herniated Nucleus Pulposus: A Systematic Review and Meta-analysis.

ContextRadiofrequency therapy is a medical procedure mainly used to reduce pain with a low complication rate (less than 1%), ease of application, and low cost. This review’s objective was to (1) evaluate the pulsed radiofrequency (PRF) effectiveness in treating radicular pain and (2) assess the PRF procedure’s safety in managing radicular pain in lumbar herniated nucleus pulposus (HNP).MethodsA systematic review and meta-analysis. A tertiary care center and an academic medical center. Six full articles with the following features were selected for this review: (1) Articles published in English; (2) studies on the PRF effect on radicular pain in lumbar HNP; and (3) randomized control trials.ResultsThe studies showed that the PRF group had a reduction in pain scores at each evaluation. In four of the studies, the PRF group showed a more significant reduction in pain scores than the control, and in two of the studies, the reduction in pain scores was not significant in the PRF group compared to the control. An adverse effect was reported in one patient experiencing increased radicular pain after PRF. Lack of data required for statistical analysis, and lack use of a uniform duration for the PRF procedure by all the studies.ConclusionsPRF can be used as a promising clinical recommendation for pain management with minimally invasive radicular pain techniques due to lumbar HNP.

Long-term Outcomes of Computerized Tomography-Guided Sphenopalatine Ganglion-Targeted Pulsed Radiofrequency for Refractory Cluster Headache.

To further evaluate the efficacy and safety of computerized tomography-guided sphenopalatine ganglion-targeted pulsed radiofrequency treatment for patients with refractory episodic and chronic cluster headache (CH). Forty-five patients with refractory episodic CH and 14 patients with chronic CH who underwent computerized tomography-guided sphenopalatine ganglion-targeted pulsed radiofrequency between January 2011 and December 2018 at the Beijing Tiantan Hospital were included and analyzed in this retrospective cohort study. A total of 59 patients underwent 106 computerized tomography-guided pulsed radiofrequency procedures throughout the observational period. Effective remission was observed in 95.6% and 64.3% of patients with refractory episodic and chronic CH, respectively. Repeated computerized tomography-guided sphenopalatine ganglion-targeted pulsed radiofrequency procedures for recurrent CH was also proven to be effective. No severe side effects or complications were observed in this study. The computerized tomography-guided sphenopalatine ganglion-targeted pulsed radiofrequency procedure is an effective, safe, and repeatedly effective strategy for refractory CH. For patients who have not responded to conservative treatment, this minimally invasive intervention is a reliable alternative.

Microglial BDNF, PI3K, and p-ERK in the Spinal Cord Are Suppressed by Pulsed Radiofrequency on Dorsal Root Ganglion to Ease SNI-Induced Neuropathic Pain in Rats.

Background Pulsed radiofrequency (PRF) on the dorsal root ganglion (DRG) has been applied to alleviate neuropathic pain effectively, yet the mechanisms underlying pain reduction owing to this treatment are not clarified completely. The activated microglia, brain-derived neurotrophic factor (BDNF), phosphatidylinositol 3-kinase (PI3K), and phosphorylated extracellular signal-regulated kinase (p-ERK) in the spinal cord were demonstrated to be involved in developing neuropathic pain. Also, it has been just known that PRF on DRG inhibits the microglial activation in nerve injury rats. Here, we aim to investigate whether PRF treatment could regulate the levels of BDNF, PI3K, and p-ERK in the spinal cord of rats with spared nerve injury (SNI) via suppressing the spinal microglia activation to ease neuropathic pain. Methods The rats with SNI were intrathecally treated with minocycline (specific microglia inhibitor) or same volume of dimethyl sulfoxide once daily, beginning from 1 h before nerve transection to 7 days. PRF was applied adjacent to the L4-L5 DRG of rats with SNI at 45 V for 6 min on the seventh postoperative day, whereas the free-PRF rats were treated without PRF. The withdrawal thresholds were studied, and the spinal levels of ionized calcium-binding adapter molecule 1 (Iba1), BDNF, PI3K, and p-ERK were calculated by western blot analysis, reverse transcription-polymerase chain reaction, and immunofluorescence. Results The paw withdrawal mechanical threshold and paw withdrawal thermal latency decreased in the ipsilateral hind paws after SNI, and the spinal levels of Iba1, BDNF, PI3K, and p-ERK increased on day 21 after SNI compared with baseline (P < 0.01). An intrathecal injection of minocycline led to the reversal of SNI-induced allodynia and increase in levels of Iba1, BDNF, PI3K, and p-ERK. Withdrawal thresholds recovered partially after a single PRF treatment for 14 days, and SNI-induced microglia hyperactivity, BDNF upregulation, and PI3K and ERK phosphorylation in the spinal cord reduced on D14 due to the PRF procedure. Conclusion Microglial BDNF, PI3K, and p-ERK in the spinal cord are suppressed by the therapy of PRF on DRG to ease SNI-induced neuropathic pain in rats.

Transforaminal Epiduroscopy in Patients with Failed Back Surgery Syndrome

Background: Epiduroscopy is a useful diagnostic and therapeutic tool for managing failed back surgery syndrome (FBSS). The conventional approach is via either the sacral hiatus or the interlaminar. Major causes of FBSS include epidural fibrosis, disc herniation, and stenosis. When these problems are located at the intervertebral foramen level, it can be difficult to reach the lateral recess and the foramen with the epiduroscope. Transforaminal epiduroscopy could be a useful alternative approach in patients with FBSS located at the foraminal level. Objective: We present a new procedure for lumbar epiduroscopy via a transforaminal approach and its application in patients with FBSS. The technique is described and long-term results are reported. Study Design: This study used a single-arm prospective observational design. Setting: The research took place at the University Hospital in Spain. Methods: Patients with FBSS suffering severe chronic radicular pain (Numeric Rating Scale [NRS11] &gt; 7) who had not responded to other treatments were included. Selective root stimulation during a pulsed radiofrequency procedure confirmed the origin of pain by means of an exact reproduction of typical pain. Transforaminal epiduroscopy was performed at the affected level. The severity of fibrosis observed was recorded. The NRS-11 score was reevaluated at 1, 6, and 12 months after the procedure. Any complications related to the treatment were recorded. Results: Twenty-four patients were included. The mean number of back surgeries was 1.66 (range, 1-5). The basal NRS-11 score was 7.83 (0.14); at 1 month, 3.66 (0.38) (P &lt; 0.001); at 6 months, 4.46 (0.48) (P &lt; 0.01); and at 1 year after treatment, 4.17 (0.51) (P &lt; 0.01). Most patients (54%; 95% CI, 34%-74%) obtained &gt; 50% pain reduction on the NRS-11, maintained during a 1-year follow-up period. No major complications were registered. Limitations: The research was limited by the lack of a control group. Conclusions: We have described a new procedure for epiduroscopy via the transforaminal approach. It is a useful and safe approach to managing FBSS at the foraminal level and shows better long-term results than other endoscopic procedures. Key words: Epidural, epiduroscopy, chronic pain, spinal cord, back surgery

Pulsed radiofrequency lesioning at multiple trigger points around the scar for management of chronic persistent postsurgical neuropathic pain following total abdominal hysterectomy and laparotomy

Chronic persistent postsurgical pain (CPPP) is a common complication following surgery. If a pain persists for >3 months following surgery and cannot be explained by any other causes, then it is labeled as CPPP. The mechanism is not fully understood. A 35-year-old female presented with chronic persistent postsurgical neuropathic pain following total abdominal hysterectomy and gynecological laparotomy. Multimodal integrated approach for the management of pain was adopted. After having no relief with oral pregabalin therapy, the patient was then planned for pulsed radiofrequency (PRF) lesioning at multiple trigger points along the scar. The patient was followed up to 6 months after the second PRF procedure. After 2 months following the PRF procedure, the Numerical Rating Scale score improved from 9/10 to 2/10.

Effect of Pulsed Radiofrequency Treatment on the Thoracic Medial Branch for Managing Chronic Thoracic Facet Joint Pain Refractory to Medial Branch Block with Local Anesthetics.

To evaluate the effect of pulsed radiofrequency (PRF) stimulation of the thoracic medial branch of the dorsal ramus in patients with chronic thoracic facet joint (TFJ) pain who were refractory to medial branch block (MBB). This was a prospective, observational study. The author retrospectively reviewed data from 72 patients who had received therapeutic MBB with 0.5 mL of 2% lidocaine mixed with 0.5 mL of 0.25% bupivacaine to treat TFJ-origin upper or midback pain. Of these patients, 20 were included to evaluate the effects of PRF on the thoracic medical branch to manage TFJ pain refractory to therapeutic MBB. PRF stimulation was administered at 5 Hz and a 5-millisecond pulsed width for 360 seconds at 45 V. The pain-reducing effect of the PRF procedure was evaluated via the numeric rating scale (NRS) at 1, 2, and 3 months after treatment. Successful pain relief was defined as ≥50% reduction in the NRS score compared with the score before treatment. The NRS scores changed significantly over time (pretreatment, 6.0 ± 1.0; 1 month, 3.3 ± 2.2; 2 months, 3.9 ± 2.1; and 3 months, 4.0 ± 2.2). At 1, 2, and 3 months after the PRF procedure, the NRS scores were significantly reduced compared with the scores before the treatment. Eleven (55%) of 20 patients reported successful pain relief at 3 months after PRF. The author suggests that PRF on the thoracic medial branch is an effective and safe interventional technique for the control of chronic TFJ pain.

Pulse-dose radiofrequency treatment in pain management-initial experience.

Radiofrequency procedures have been used for treating various chronic pain conditions for decades. These minimally invasive percutaneous treatments employ an alternating electrical current with oscillating radiofrequency wavelengths to eliminate or alter pain signals from the targeted site. The aim of the continuous radiofrequency procedure is to increase the temperature sufficiently to create an irreversible thermal lesion on nerve fibres and thus permanently interrupt pain signals. The pulsed radiofrequency procedure utilises short pulses of radiofrequency current with intervals of longer pauses to avert a temperature increase to the level of permanent tissue damage. The goal of these pulses is to alter the processing of pain signals, but to avoid relevant structural damage to nerve fibres, as seen in the continuous radiofrequency procedure. The pulse-dose radiofrequency procedure is a technical improvement of the pulsed radiofrequency technique in which the delivery mode of the current is adapted. During the pulse-dose radiofrequency procedure thermal damage is avoided. In addition, the amplitude and width of the consecutive pulses are kept the same. The method ensures that each delivered pulse keeps the same characteristics and therefore the dose is similar between patients. The current review outlines the pulse-dose radiofrequency procedure and presents our institution's chronic pain management studies.

Management of Refractory Sciatic Neuropathic Pain Using Ultrasound-Guided Pulsed Radiofrequency

Nowadays, pulsed radiofrequency (PRF) is being used to control several types of musculoskeletal pain. Herein, we report a successful application of ultrasound (US)-guided PRF for a patient with refractory sciatic neuropathic pain. Case report. We applied US-guided PRF to a 50-year-old man, suffering from refractory neuropathic pain on the left foot following sciatic neuropathy for a period of approximately 6 months. We performed PRF on the level of piriformis muscle because the lesion of the sciatic nerve was presented digitally from the level of piriformis muscle on the magnetic resonance images. Under US guidance, the catheter needle was placed close to the left sciatic nerve, and dysesthesia and tingling sensation were reported to be less than 0.2V. The PRF treatment was administered at 5Hz and 5ms pulsed width for 360 seconds at 45V. After PRF on the left sciatic nerve, pain intensity-based on a numeric rating scale-decreased from 8 to 2. The reduction of pain was sustained for at least 6 months after the PRF procedure. We concluded that the PRF treatment with guidance with US is a very useful treatment technique for patients with refractory sciatic neuropathy.

Pulsed Radiofrequency Spinal Cord Neuromodulation for Residual Symptoms after Cervical Surgery

Introduction Cervical decompression, discectomy, fusion, and arthroplasty are treatment modalities of choice for various pathological conditions of cervical spine. Occasionally after these procedures, some degree of neck pain, paresthesia, and/or palsy may still be reported by patients. Pulsed radiofrequency (PRF) neuromodulation of spinal cord dorsal root entry zone, pregangliar and postgangliar nerve root parts, is a well-known invasive pain therapy modality used for a variety of pain symptoms. This study was done to evaluate if a single session, PRF neuromodulation, might be effective in the treatment of residual symptoms after cervical surgical procedures. Materials and Methods Thirty-eight patients from three different clinical settings were included in the study. Eighteen patients have been previously submitted to one- or two-level anterior discectomy and interbody fusion, 10 patients to two or more level anterior discectomy, decompression, and fusion, 7 patients had a one- to two-level arthroplasty performed, while the rest had a posterior decompression with or without instrumented fusion. Upon surgery, 22 patients reported some residual symptoms mainly of neck pain, radiating pain to scapular and/or shoulder area, and 15 of them had only or also paresthesia and/or pain radiating to one or both upper limbs. Four patients also had some degree of residual palsy that did not improve completely after the surgery. The neuromodulation procedure was performed not less than 3 months after the surgery (mean time from surgery to PRF treatment was 4.5 months). In all the cases, the PRF procedure was done by Pasha-catheter that was introduced inside the vertebral channel at the midthoracic level, interlaminary, and under local anesthesia only. In the cases of neck pain, extradural treatment of dorsal root entry zones, pregangliar and occasionally postgangliar nerve fibers at multiple levels from C2 to D1, was done bilaterally. In the cases of symptoms radiating to the upper limbs, the treatment was mainly focused on the side of the symptoms and the treatment was centered on dorsal root entry zones and preganglionic fibers. When the residual palsy was present, the preferred treatment was intrathecal treatment of the dorsal root entry zone and the ganglion area. The mean treatment duration was 58 ± 14 minutes. Except when an intradural modality of treatment was performed, all the patients were discharged on the same day after a 6-hour in-hospital observation. The intradurally treated patients were discharged the next morning. In 3 cases, posttreatment headache was reported in the first 24 hours, while in 10 cases the pain was at the introduction site. No short- or long-term complications were observed. Results At 2-month follow-up, 34 patients reported significant improvement in pain levels while at 1-year follow-up, 29 patients were still reporting significant improvement in pain levels as compared with preoperative status. Preoperative mean VAS value for all the patients was 5.5 ( ± 2) and the 1-year reduction evaluation was 1.5 ( ± 1). Out of the four patients with residual palsy, two patients were found almost free of the palsy, one patient did not improve at all, and another had just partial improvement in the strength. Conclusion The PRF neuromodulation of the spinal cord and gangliar structures seems to be reasonably useful for the treatment of the residual pain and neurological symptoms after different cervical surgical procedures.

The Effect of Pulsed Radiofrequency Applied to the Peripheral Nerve in Chronic Constriction Injury Rat Model.

ObjectiveTo investigate the effect of pulsed radiofrequency (PRF) applied proximal to the injured peripheral nerve on the expression of tumor necrosis factor-α (TNF-α) in a neuropathic pain rat model.MethodsNineteen male Sprague-Dawley rats were used in the study. All rats underwent chronic constriction injury (CCI) procedure. After 7 days of CCI, withdrawal frequency of affected hind paw to mechanical stimuli and withdrawal latency of affected hind paw to heat stimulus were measured. They were randomly divided into two groups: group A, CCI group (n=9) and group B, CCI treated with PRF group (n=10). Rats of group B underwent PRF procedure on the sciatic nerve. Withdrawal frequency and withdrawal latency were measured at 12 hours, and 7 days after PRF. Immunohistochemistry and Western blot analysis were performed using a TNF-α antibody.ResultsBefore PRF, withdrawal frequency and withdrawal latency were not different in both groups. After PRF, withdrawal frequency decreased and withdrawal latency prolonged over time in group B. There was significant interaction between time and group for each withdrawal frequency and withdrawal latency. Group B showed decreased TNF-α immunoreactivity of the spinal cord and sciatic nerve at 7 days.ConclusionPRF applied proximal to the peripheral nerve injury is potentially helpful for the reduction of neuropathic pain by neuromodulation of inflammatory markers.