Radiofrequency Ablation Of Nerves Research Articles

Ultrasound-guided radiofrequency ablation of genicular nerves of knee for relief of intractable pain from knee osteoarthritis: a case series.

The knee arthroplasty is the best option for patients with advanced osteoarthritis who have failed all other conservative options, but regrettably many patients fail to undergo surgery due to co-morbidities or other reasons. So, new alternative modes are always in demand for these patients. The ultrasound-guided radiofrequency ablation (RFA) of all the genicular nerves of knee joint was done in patients with grade III and IV osteoarthritis of knee joint, with severe pain (numerical rating scale (NRS) > 7) who had failed conservative management and intra-articular injections after a positive genicular nerve block with local anaesthetics. The demographics, pain intensity measured in NRS, Oxford Knee Score (OKS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and quality of life measured by 36-Item Short Form Health Survey (SF-36) questionnaire was measured at baseline and at regular intervals. The average age of the patients was 61.50 ± 6.75 years. There was significant improvement in pain intensity at rest, movement and on weight bearing from 8.75 ± 0.5, 9.0 ± 0.0, and 9.0 ± 0.0 at baseline to 2.38 ± 0.51, 3.75 ± 0.46, and 4.13 ± 0.35 at 1 month and 3.13 ± 0.64, 4.38 ± 0.51, and 4.63 ± 0.51 at 6 months after the procedure, respectively (p value <0.05). The OKS had improved from 7.75 ± 1.25 at baseline to 28.88 ± 2.53 and 28.13 ± 1.80 at 1 and 6 months, respectively, after the procedure (p value <0.05). The WOMAC score had also improved significantly from 77.75 ± 4.34 at baseline to 38.38 ± 5.82 and 39.25 ± 5.12 at 1 and 6 months, respectively (p value <0.05). There was also significant improvement in the quality of life after the procedure (p value <0.05). Ultrasound-guided RFA of genicular nerves of knee joint is a good alternative option for patients who are having severe pain and disability from knee osteoarthritis and gives a long-lasting pain relief for more than 6 months.

Magnetic-Resonance Tomography for Anthropometric Value of Kidneys and Adrenals in Prognosis Efficiency of Renal Sympathetic Denervation in Patients with Treatment-Resistant Hypertension

Aim: to evaluate the possible role of contrast-enhanced MRI studies of the kidneys in prognosis of clinical effect of the renal denervation treatment of the resistant hypertension.Material and methods. 24 patients (57.8 ± 8.75 years) with resistant hypertension were included, in everybody the radiofrequency ablation (RFA) of the sympathetic nerves of renal arteries was carried out. The average 24-h monitor of the arterial pressure was as 137–210/57–148 mm Hg. The MRI studies were performed using MRI scanner “Titan Vantage” (by “Toshiba Medical Ltd”, with the field induction 1.5 Т). After this the intravenous contrast enhancement has been carried out (with 0.5 М solution, 0.2 ml/Kg), with repeat acquisition of Т1-weighted spin-echo images in3–5 min after contrast injection.Results.MRI was employed for quantitative calculation of renal volumes of cortex, medulla and of kidney as total, as well as of suprarenal’s volume. Significant negative correlation of postoperation decrease of arterial pressure has been detected with both volume of renal cortex, as {Decrease in AP = 42.7–0.35 • (V left kidney)}, and also with mass of the right suprarenal gland as {Decrease in SAP = 16.5–6.78 • • (V right suprarenal)}.Conclusion.The anatomic quantitative data of the preoperativeMRI studies of the kidneys can be employed as prognostic tool in patients referred to the renal denervation treatment of the resistant hypertension.

Cooled Radiofrequency Ablation of the Genicular Nerves for Chronic Pain due to Knee Osteoarthritis: Six-Month Outcomes.

Determine outcomes of cooled radiofrequency ablation (C-RFA) of the genicular nerves for treatment of chronic knee pain due to osteoarthritis (OA). Cross-sectional survey. Academic pain medicine center. Consecutive patients with knee OA and 50% or greater pain relief following genicular nerve blocks who underwent genicular nerve C-RFA. Survey administration six or more months after C-RFA. Pain numeric rating scale (NRS), Medication Quantification Scale III (MQSIII), Patient Global Impression of Change (PGIC), and total knee arthroplasty (TKA) data were collected. Logistic regression was used to identify factors that predicted treatment success. Thirty-three patients (52 discrete knees) met inclusion criteria. Thirty-five percent (95% confidence interval [CI] = 22-48) of procedures resulted in the combined outcome of 50% or greater reduction in NRS score, reduction of 3.4 or more points in MQSIII score, and PGIC score consistent with "very much improved/improved." Nineteen percent (95% CI = 10-33) of procedures resulted in complete pain relief. Greater duration of pain and greater than 80% pain relief from diagnostic blocks were identified as predictors of treatment success. The accuracy of the model was 0.88 (95% CI = 0.78-0.97, P < 0.001). Genicular C-RFA demonstrated a success rate of 35% based on a robust combination of outcome measures, and 19% of procedures resulted in complete relief of pain at a minimum of six months of follow-up. Report of 80% or greater relief from diagnostic blocks and duration of pain of less than five years are associated with high accuracy in predicting treatment success. Further prospective study is needed to optimize the patient selection protocol and success rate of this procedure.

Cooled Radiofrequency Ablation of Genicular Nerves for Knee Osteoarthritis Pain: A Letter to Editor.

Cooled Radiofrequency Ablation of Genicular Nerves for Knee Osteoarthritis Pain: A Letter to Editor.

A Review of Long-Term Pain Relief after Genicular Nerve Radiofrequency Ablation in Chronic Knee Osteoarthritis

Background: Studies of radiofrequency ablation (RFA) of genicular nerves have reportedly significantly decreased pain up to 3 months post ablation, but no longer term effects have been reported. We performed an analysis of long-term pain relief of 31 RFA procedures of the genicular nerves to analyze the degree of pain relief past 3 months, culminating at 6 months. Objective: To evaluate the long term efficacy of genicular nerve ablation for management of chronic knee pain due to osteoarthritis. Study Design: Chart review and study design was approved by Newark Health Sciences IRB. Chart review and follow-up was performed on all patients who underwent genicular nerve RFA during the period of February 2014 through August of 2015. During this inclusion period 41 genicular nerve RFAs were performed on 31 patients, 5 patients received RFA procedure in both knees. Patient follow-up was performed via telephone interview or in-office visit at least 3 months and 6 months post RFA. Settings: Procedures were performed in Medical Special Procedures at University Hospital in Newark, NJ, and the Pain Management Center at Overlook Medical Arts Center in Summit, NJ. Methods: Chart review and study design was approved by Newark Health Sciences Institutional Review Board. Chart review was performed from February 2014 and continued through August 2015. Patient follow-up was conducted at 3 and at least 6 months post treatment to gauge degree of pain relief (0 – none, 100% – complete), their current day’s pain score, other treatment modalities tried before RFA, and the medications used. Patients were asked to quantify their satisfaction with procedure length, pre-procedure anxiety, complications, and if they would recommend this procedure to others. Primary and secondary goals were the duration of pain relief after RFA, the quality of pain relief, and the efficacy of our approach for RFA of genicular nerves versus prior published techniques. Results: At 3 month follow-up, the average pain relief was 67% improvement from baseline knee pain, 0% being no relief and 100% being complete relief, and average 0 – 10 pain score was 2.9. At 6 month follow-up, of those who described pain relief at 3 months, 95% still described pain relief. This group’s average percent pain relief was 64% and average day’s 0 – 10 pain score 3.3. Limitations: Our study included a retrospective component in chart review followed by prospective follow-up, only 76% of patients were able to participate in the interview process. Furthermore, some patients suffered from other chronic pain ailments, most commonly chronic back pain, which at times disturbed the patient’s ability to focus on solely knee pain. Conclusions: Based on patient interviews and data collection, RFA of genicular nerves can supply on average greater than 60% pain relief in our patient population for as long as 6 months. Key words: Osteoarthritis, knee osteoarthritis, chronic knee pain, radiofrequency ablation, nerve ablation, genicular nerves, long-term pain relief

Radiofrequency Ablation of Genicular Nerves in Pain Management in Chronic Knee Pain

Radiofrequency Ablation of Genicular Nerves in Pain Management in Chronic Knee Pain

EVALUATION OF THE INFLUENCE OF RENAL CYSTS ON THE LEVEL OF ARTERIAL PRESSURE REDUCTION AFTER RENAL DENERVATION IN PATIENTS WITH RESISTANT HYPERTENSION. THE BIENNIAL INSPECTION

Aim. We evaluated the influence of renal cysts on the efficiency of reduction of arterial pressure in patients with treatment-resistant hypertension after renal denervation. Materials and Methods. A total of 33 patients (aged 57.8±8.75 years) with treatment-resistant hypertension were included. All patients underwent radiofrequency ablation (RFA) of the sympathetic nerves of renal arteries. The average level of arterial pressure was as high as 137–210/57–148 mm Hg according to 24-h monitoring. MRI studies were performed using MRI scanner “Titan Vantage” (by Toshiba Medical Ltd., 1.5 Т) in T1-W and T2-W spin-echo models. After this, the intravenous contrast enhancement was carried out (with 0.5 М solution, 0.2 ml/Kg), with subsequently repeated acquisition of Т1-weighted spin-echo images 3-5 min after contrast injection, employing exactly the same protocols as before enhancement. Results. Preoperative images demonstrated cysts in kidneys in half of patients (16 individuals). Positive effect (the arterial pressure decreased by 10 mm Hg) was observed in 70% of them. However, in 30% of population, the arterial pressure increased. Among the patients without cysts in the kidneys, negative effect was observed in 8% only, and positive effect was found in 77% of patients (arterial pressure decreased by over 20 mm Hg). Conclusion. There is a statistically significant trend towards a greater antihypertensive effect of renal denervation in patients without cystic changes in the renal parenchyma (cortex). Thus, MRI is of prognostic value for prediction of renal denervation efficacy.

Analgesic Effect and Functional Improvement Caused by Radiofrequency Treatment of Genicular Nerves in Patients With Advanced Osteoarthritis of the Knee Until 1 Year Following Treatment.

Radiofrequency ablation of genicular nerves has proved to be successful in relieving pain and incapacity caused by osteoarthritis of the knee. However, long-term efficacy of such a treatment remains to be assessed. The current study aimed to reproduce radiofrequency neurotomy of genicular nerves to manage gonarthrosis pain and disability and establish therapeutic response until 1 year after intervention. This single-center, prospective, observational, noncontrolled, longitudinal study included patients with grade 3 to 4 gonarthrosis suffering from intractable knee pain, scoring 5 or more on the visual analog scale (VAS) during >6 months. Therapy was based on ultrasound guided radiofrequency neurotomy of the superior medial, superior lateral and inferior medial genicular nerves. Visual analog scale and Western Ontario and McMaster Universities Osteoarthritis scores were assessed before therapy and at 1, 6, and 12 months following treatment. Radiofrequency neurotomy of genicular nerves significantly reduced perceived pain (VAS) and disability (Western Ontario and McMaster Universities Osteoarthritis) in the majority of participants, without untoward events. The proportion of participants with improvement of 50% or greater in pretreatment VAS scores at 1, 6, and 12 months following intervention were 22/25 (88%), 16/25 (64%) and 8/25 (32%), respectively. Ultrasound-guided radiofrequency neurotomy of genicular nerves alleviates intractable pain and disability in the majority of patients with advanced osteoarthritis of the knee. Such a treatment is safe and minimally invasive and can be performed in an outpatient setting. The beneficial effect of treatment started to decline after 6 months, but even 1 year after the intervention, 32% of patients reported 50% improvement or greater in pretreatment VAS scores.

Splanchnic nerve radiofrequency ablation for treating resistant abdominal pain.

Splanchnic nerve radiofrequency ablation for treating resistant abdominal pain.

Radiofrequency ablation of bilateral splanchnic nerve in acute pancreatitis pain: Interventional approach.

Sir, Radiofrequency ablation (RFA) of the bilateral splanchnic nerve has been used in patients with chronic pancreatitis pain refractory to medical management.[1] We describe the management of pain in acute pancreatitis using RFA ablation of bilateral splanchnic nerve. A 37-year-old male presented with chief complaints of severe pain abdomen radiating to back and vomiting since 6-months. The pain aggravated following meals and was not relieved with analgesics. The verbal numeric rating scale (VNRS)[2] was 9/10. Patient was chronic alcoholic since 25 years. Blood investigations were within acceptable range. Computed tomography (CT) of the abdomen showed bulky and heterogeneous pancreas with necrosis (>50%) in body and tail of pancreas sparing the head region [Figure 1a] with modified CT severity index of 10. A large collection 9 cm × 6 cm was present in the lesser sac, which was managed with the ultrasound-guided aspiration of a pseudocyst. The patient showed clinical improvement, but the VNRS continued to be 8/10 in spite of analgesics. Patient had received several trials of the combination of analgesics including; paracetamol, tramadol, paracetamol-codeine phosphate combination, tapentadol, flupirtine, and adjuvant medications like pancreatic enzyme supplementation, with no relief in symptoms. A CT scan done after 4 weeks revealed a bulky pancreas with heterogeneous density with modified CT severity index of 6 for which no surgical intervention was required. Patient was referred to a pain clinic. After explaining the procedure to the patient and written informed consent, RFA of bilateral splanchnic nerve was planned. An intravenous access (IV) was placed and 1 L normal saline was administered. Monitoring (Aestiva 5™, GE healthcare, Datex-Ohmeda division, Helsinki, Finland) was started and IV fentanyl 50 μg and diclofenac 50 mg were administered to reduce pain related to the prone position. Under strict asepsis and fluoroscopic guidance a 20G, 10 cm RF needle with 10 mm curved active tip (Cosman cannula RFK™ Cosman Medical, Inc., Burlington, MA, USA) was placed at the junction of anterior one-thirds and posterior two-thirds of T11 vertebral body [Figure 1b] and after confirmation with nonionic radio-opaque contrast, sensory stimulation was confirmed at 50-Hz frequency and at 0.5 V [Figure 1c]. Following no motor stimulation, RFA was done at 60°C, and four cycles of 120 s each were applied. A mixture of 5 ml of 0.2% ropivacaine and 20 mg of triamcinolone was injected before removing the RF needle. A similar procedure was done on the other side. The patient's VNRS reduced to 0/10. At 1-year, VNRS remained 2/10 with improvement in quality of life and occasional requirement of mild analgesics.Figure 1: (a) Computed tomography of the abdomen, the white arrow showing necrosis of body and black arrow showing necrosis in the tail of pancreas (b) fluoroscopic image of radio frequency needle placed at the junction of anterior one-thirds and posterior two-thirds of T11 vertebral body (c) splanchnic nerve block with radio frequency needle and stimulating electrode in situPain in acute pancreatitis is transmitted via afferent splanchnic nerves of the celiac plexus.[34] Percutaneous splanchnic nerve block was performed in the present case as compared to celiac plexus block due to its predictable anatomy, accurate needle placement, and theoretically reduced the risk of complications. Under fluoroscopy, RFA is a minimally invasive target-selective technique, which heats the tissues at 65-75°C to produces thermal lesion. This interrupts the conduction of nociceptive signals and blocks the pain transmission. The duration of pain relief depends on the duration of time taken by coagulated nerves to regenerate.[5] Earlier authors had also reported a reduction in the pain after RFA in patients with chronic pancreatitis.[67] Pain during acute pancreatitis offers more challenges, as patients are clinically less stable than in chronic pancreatitis. Prone position may require additional analgesics due to discomfort and pain during RFA procedure.[5] Application of bilateral splanchnic nerve RFA may be considered for pain relief in moderately severe acute pancreatitis. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Lumbar Facet&ndash;Mediated Pain

Lumbar or lower back pain is a very debilitating condition that affects almost one fifth of the adult population during a given year. Almost everyone walking on two feet is bound to suffer from some back pain during their lifetime. The health care burden for treating low back pain is enormous, especially if the lost work hours are combined with the amount used in diagnosing and treating low back pain. Lumbar facet (zygapophysial) joints are one of the major components involved in causing lower back pain. Diagnosing the pain generator is more of an art than a science. Combining various parameters in the patient’s history, physical examination, and diagnostic studies is not much different from solving a murder mystery. Although facet joint pain may be accompanied by other pain generators, that is, lumbar intervertebral disks, nerve roots, and vertebral bodies, once treated, the relief in pain is more helpful in performing proper rehabilitation and improving further deterioration in low back pain. Muscles are almost always painful due to myofascial pain syndrome that accompanies the facet joint–related pain. Treating one without addressing the other leads to failure in management and optimization of patient’s pain and function. Several treatments are available for treatment of facet joint–mediated pain, including steroid injections using a miniscule amount and radiofrequency ablation of the nerves supplying the facet joints (medial branches of the dorsal primary ramus of the lumbar nerve root). With proper diagnosis and treatment, a patient’s pain and function can be optimized to a level where it may not impact the day-to-day activities or even resumption of the patient’s routine job function. The following review describes the anatomy, pathophysiology, diagnosis, and treatment of lumbar facet joint–mediated pain. Key words: facet joint pain, facet joint syndrome, low back pain, medial branch radiofrequency, spondylolisthesis

Evaluation of Migraine Surgery Outcomes through Social Media.

Background:Social media have been used to study many aspects of health and human behavior. Although social media present a unique opportunity to obtain unsolicited patient-reported outcomes, its use has been limited in plastic and reconstructive surgical procedures, including migraine nerve surgery. The goal of this study was to utilize the most popular social media site, Facebook, to evaluate patients’ experience with migraine surgery.Methods:Six months of data regarding nerve surgery, nerve stimulators, and radiofrequency nerve ablation were collected from posts and comments written by members of 2 Facebook groups. Outcomes were classified by degree of resolution of symptoms.Results:A total of 639 posts related to migraine surgery. Of 304 posts commenting on postoperative success of nerve surgery, 16% reported elimination of headaches and 65% significant improvement (81% with complete or significant improvement), 5% partial improvement, 11% no change, and 3% worsening symptoms. Nerve surgery had a higher success rate than nerve stimulators and radiofrequency ablation. Nerve surgery was recommended by 90% of users.Conclusions:The 81% rate of complete or significant improvement of symptoms in this study is close to the 79% to 84% shown in current literature. Similar to the findings of a recent systematic review, surgery is more efficacious compared with nerve stimulators and ablation. This study adds to evidence favoring migraine surgery by removing evaluator bias and demonstrates that surgical outcomes and satisfaction data may be obtained from social media.

Currently Recommended TON Injectate Volumes Concomitantly Block the GON: Clinical Implications for Managing Cervicogenic Headache

Background: Headache (HA) is a significant cause of morbidity globally. Despite many available treatment options, HAs that are refractory to conservative management can be challenging to treat. Third occipital nerve (TON) and greater occipital nerve (GON) irritation are potential etiologic agents of primary and cervicogenic HAs that can be targeted using minimally invasive treatment options such as nerve blocks or radiofrequency ablation. However, a substantial number of patients that undergo radiofrequency ablation do not experience pain relief despite a positive diagnostic medial branch block (MBB). Objective: In this study, we investigate the underlying cause for the high rate of false positives associated with MBBs by evaluating injectate spread in cadaveric subjects. Study Design: Cadaveric study. Setting: Academic medical center. Methods: After obtaining exemption status from our Institutional Review Board, TON injections were performed on 5 preserved cadavers, a total of 10 TONs, using anatomic landmarks, partial dissection, and palpation to guide needle placement. Cadaveric dissections were performed to evaluate the location, vertical spread, and grossly observed injectate coating of the TON and GON for each quantity of methylene blue injectate, 0.3 mL and 0.5 mL, administered. Results: The average distance between the TON and GON at their respective foraminal exit points was 1.81 cm. The average vertical spread for 0.3 mL and 0.5 mL of methylene blue injectate was 2.02 + 0.35 cm and 3.26 + 0.48 cm when performing a TON block. When using 0.3 mL injectate, both the TON and GON were simultaneously coated 60% of the time. After increasing the injectate volume to 0.5 mL, both the TON and GON were simultaneously coated 100% of the time. Limitations: The cadaveric design of this study presents limitations when translating cadaveric findings to the clinical setting. Also, the small sample size limits its power and generalizability. Lastly, the potential for researcher bias exists as the investigators were not blinded. Conclusions: This study demonstrates that currently recommended injectate volumes for TON blocks may result in concomitant coating of the GON. Conventional radiofrequency ablation (RFA) of these nerves may not lesion both the TON and GON given its restrictive circumferential lesioning diameter of 5 – 7 mm. As such, interventionalists should consider performing radiofrequency ablation to both the TON and GON after a positive TON block. Key Words: Chronic pain, cervicogenic headache, third occipital nerve, greater occipital nerve, injectate spread, radiofrequency ablation

Cooled Radiofrequency Ablation of Genicular Nerves for Knee Osteoarthritis Pain: A Protocol for Patient Selection and Case Series.

BackgroundChronic knee pain from osteoarthritis (OA) is common in the aging and the obese population. Radiofrequency ablation of the genicular nerves has been introduced as a potential surgery-sparing treatment for chronic knee pain from OA, yet only two outcome studies have been published and optimal patient selection for this procedure has not been established.ObjectivesWe describe a standardized protocol for selecting patients for cooled radiofrequency ablation (C-RFA) of the genicular nerves, as well as the clinical outcomes of four patients ages 63-65 years.MethodsThe threshold for selection based on diagnostic genicular nerve block was ≥ 80% pain reduction. Following successful block, C-RFA of the genicular nerves was performed. Outcomes included pain, function, analgesic medication use, opioid use, and progression to total knee arthroplasty at a minimum of 6 month follow up.ResultsC-RFA of the genicular nerves after using the described selection protocol resulted in > 90% pain reduction, improved function and avoidance of surgery at 6 months in all four cases. All opioid and analgesic medication use decreased or was unchanged in all cases. No serious adverse events occurred.ConclusionsThe accompanying case series suggests that this protocol is deserving of randomized, prospective study.

Is Genicular Nerve Radiofrequency Ablation Safe? A Literature Review and Anatomical Study

Genicular nerve radiofrequency ablation (RFA) has recently gained popularity as an intervention for chronic knee pain in patients who have failed other conservative or surgical treatments. Long-term efficacy and adverse events are still largely unknown. Under fluoroscopic guidance, thermal RFA targets the lateral superior, medial superior, and medial inferior genicular nerves, which run in close proximity to the genicular arteries that play a crucial role in supplying the distal femur, knee joint, meniscus, and patella. RFA targets nerves by relying on bony landmarks, but fails to provide visualization of vascular structures. Although vascular injuries after genicular nerve RFA have not been reported, genicular vascular complications are well documented in the surgical literature. This article describes the anatomy, including detailed cadaveric dissections and schematic drawings, of the genicular neurovascular bundle. The present investigation also included a comprehensive literature review of genicular vascular injuries involving those arteries which lie near the targets of genicular nerve RFA. These adverse vascular events are documented in the literature as case reports. Of the 27 cases analyzed, 25.9% (7/27) involved the lateral superior genicular artery, 40.7% (11/27) involved the medial superior genicular artery, and 33.3% (9/27) involved the medial inferior genicular artery. Most often, these vascular injuries result in the formation of pseudoaneurysm, arteriovenous fistula (AVF), hemarthrosis, and/ or osteonecrosis of the patella. Although rare, these complications carry significant morbidities. Based on the detailed dissections and review of the literature, our investigation suggests that vascular injury is a possible risk of genicular RFA. Lastly, recommendations are offered to minimize potential iatrogenic complications. Key words: Genicular nerve, genicular artery, radiofrequency ablation, genicular vascular injury, knee osteoarthritis, patella injury

Near Death Experience from Placement of an Intrathecal Catheter

The management of pain due to cancer is challenging and often requires invasive therapy in addition to medication management. Intrathecal drug delivery is a form of advanced therapy that delivers medication locally in the intrathecal space while reducing systemic side effects associated with high doses of opioids. Although risks associated with intrathecal drug delivery are low, some common complications include dislodgement, kinking, or fracture of the catheter, bleeding, neurological injury, infection, and cerebrospinal leaks. We present a case of a 38-year-old woman with a medical history significant for stage IV breast cancer, L2 metastatic lesion, opioid tolerance, and chronic neck and low back pain who was admitted to the hospital for intractable pain. She had failed multiple interventional procedures in the past including lumbar medial nerve radiofrequency ablation, epidural steroid injection, and trigger point injections as well as a kyphoplasty at the L2 level. Failing both oral and parenteral opioid treatments, the decision was made to place an intrathecal pump in the patient. After placement of the intrathecal catheter and prior to any bolus of medication being given, the patient became bradycardic with a heart rate in the 20s and experienced a 10 second pause. The patient had intermittent bradycardia over the following days and symptoms resolved only after removal of the intrathecal catheter itself. To our knowledge, this is the first reported case with a complication of recurrent bradycardic and asystolic episodes prior to the administration of intrathecal opioid but shortly after placement of the intrathecal catheter itself. Key words: Intrathecal drug delivery, complications, cancer pain, intrathecal analgesia, bradycardia, opioids

(477) Radiofrequency ablation for chronic back pain: a comparison of two techniques of radiofrequency ablation for the management of lumbar facet syndrome

Chronic back pain is a common health issue and has a negative impact on the quality of life. The facet joints are a common source of pain. Inflammation/injury to lumbar facet joints can lead to the development of lumbar facet syndrome. We present a case of a 71-year-old female with a chronic history of lower back pain who was diagnosed with bilateral lumbar facet syndrome in 2013. She underwent conventional radiofrequency ablation (RFA) of L3, L4, and L5 medial branch nerves on the left side and endoscopic RFA of L3, L4, and L5 nerves on the right side within a one-month period in 2013. We then compared the effectiveness of both techniques on long-term pain relief. Prior to 2013, she had tried medical management, physical therapy, medial branch blocks, previous RFA, lumbar epidural and sacroiliac joint steroid injections all resulting with recurrence of pain. After undergoing both methods of RFA in 2013, her back pain has resolved for 24 months. There was insignificant difference in pain relief between conventional and endoscopic RFA. The patient had complete pain relief with conventional RFA for 15 months after which she experienced occasional, mild pain on the left side, relieved with pain medication. At 24 months, the patient has been pain free on the endoscopic side. Endoscopic guided RFA is a newer method of RFA, with the advantage of direct visualization of affected nerves, but disadvantages include longer duration of procedure, lengthened recovery time, prolonged anesthesia, increased cost, and potential cosmetic scarring. We concluded that both conventional and endoscopic RFA have similar effects on long-term pain relief. Our patient has had substantial pain relief for 24 months. Comparing the advantages and disadvantages of endoscopic versus conventional fluoroscopic guided RFA and based on the comparable outcomes, conventional fluoroscopic medial branch RFA is a preferable technique.

Recent Developments and Controversies in the Treatment of Resistant Hypertension.

Resistant hypertension is defined as elevated blood pressure despite the appropriate use of 3 or more antihypertensive drugs, including a diuretic, and constitutes a frequent and important clinical problem with significant disease morbidity and mortality. Several sources of evidence point to the sympathetic nervous system as a major protagonist in this disease entity. The catheter-based, radiofrequency ablation of renal sympathetic nerves (renal denervation) to treat resistant hypertension has sparked great enthusiasm. However, failure of this interventional approach in the randomized, sham-controlled Symplicity HTN-3 trial to reach its efficacy endpoint of attaining a significant blood pressure reduction has called this intervention into substantial question and fueled an ongoing scientific debate. Electrical stimulation of the carotid baroreceptors (baroreflex activation therapy) represents another technique to modulate sympathetic activity currently being studied in several clinical trials. This review summarizes and comments the current literature focusing on the invasive treatment of resistant hypertension.

Ultrasound-Guided Genicular Nerve Thermal Radiofrequency Ablation for Chronic Knee Pain.

Osteoarthritis (OA) of the knee is one of the most common joint diseases affecting adults in the United States. For elderly patients with multiple medical comorbidities who do not wish to undergo total knee arthroplasty (TKA), lifestyle modification, pharmacologic management, and injections are the mainstay of therapy. Previously, pain management interventions were limited to intra-articular joint injections and viscosupplementation with hyaluronic acid. Fluoroscopic-guided techniques for radiofrequency ablation (RFA) of the genicular nerves have been previously described and a recent cadaveric study suggests that ultrasound-guided genicular nerve blocks can be performed accurately. We performed an ultrasound-guided radiofrequency ablation of the genicular nerves in 88-year-old woman who had deferred surgical management given her age. Following successful ultrasound guided diagnostic genicular nerve blocks, she proceeded to RFA using the same ultrasound guided technique. The procedure resulted in significant pain relief and improvement in overall function for greater than 6 months. The use of ultrasound provides a relatively rapid and noninvasive method to directly visualize genicular nerves and surrounding vasculature. Our case suggests that, for genicular nerve blockade and RFA, ultrasound may be a useful alternative to fluoroscopy. Not only did the procedure result in significant pain relief that has persisted for greater than 6 months but also more importantly her function status and quality of life were improved.

Prolonged Pulsed Radiofrequency Ablation of Genicular Nerves of Knee for Intractable Pain from Knee Osteoarthritis: A Case Report

The literature on application of prolonged PRF of genicular nerves of knee for osteoarthritis of knee is nil. This study will provide level IV evidence that prolonged PRF is a safe and effective in treating knee pain from osteoarthritis of knee joint not responding to conservative modalities of treatment and who wants to avoid surgery.