Radiofrequency Needle Research Articles

Evaluation of clinical results of combined correction of age-related skin changes using fractional microneedle therapy and platelet-rich plasma activated by autologous thrombin.

Background. Involutive processes in the human body are often accompanied by the only visible manifestation - a change in appearance. Against this background, the search for new treatment methods that will focus on timely and rational correction of age-related skin changes and combine the possibility of complex effects on the mechanisms of skin aging is relevant. Hardware physiotherapy technologies and innovative autologous cellular preparations have a powerful regenerative potential, trigger and support physiological tissue regeneration. Despite the substantial amount of data on combined aesthetic correction protocols, there were only isolated data in the domestic and foreign literature on the combined use of fractional needle radiofrequency therapy and platelet-rich plasma activated by autologous thrombin. This was the basis for this study.
 Aims. To evaluate the results of a combined method for correcting age-related skin changes based on a combination of hardware fractional needle radiofrequency exposure and injection therapy with platelet-rich plasma activated by autologous thrombin, comparing to monotherapy the same methods.
 Materials and methods. Fractional microneedle radiofrequency therapy was carried out three times with an interval between procedures of 3 weeks with the use of a high-frequency electrosurgical device Scarlet RF. Therapy with autologous plasma rich in platelets activated by autologous thrombin (PRP therapy) was performed three times with an interval between procedures of 3 weeks without the use of preliminary topical anesthesia. Combination therapy combined the use of the above methods. Regression of clinical signs of skin aging was evaluated according to digital dermatoscopy and regression of the total value of the dermatological index of the quality of life of patients, as well as improvement of qualitative and functional parameters of the skin. A statistical analysis was carried out.
 Results. A comparative analysis of the influence of various methods of correction of involutive changes in the skin of the face showed that the use of combination therapy provides the development of the most significant clinical effect in relation to all the assessed signs of skin aging. Combination therapy was accompanied by a significant increase in the integral index of microcirculation, regardless of age. The reconstructive effect on the morphological structures of the skin according to ultrasonography also turned out to be significantly higher for the combined method of treatment in comparison with radiofrequency therapy.
 Conclusions. The combined use of fractional microneedle radiofrequency therapy and PRP therapy provides a more effective and prolonged correction of age-related skin changes compared to the monotherapy.

Randomized trial of conventional versus radiofrequency needle transseptal puncture for cryoballoon ablation: the CRYO-LATS trial

BackgroundTransseptal puncture to achieve left atrial access is necessary for many cardiac procedures, including atrial fibrillation ablation. More recently, there has been an increasing need for left atrial access using large caliber sheaths, which increases risk of perforation associated with the initial advancement into the left atrium. We compared the effectiveness of a radiofrequency needle-based transseptal system versus conventional needle for transseptal access.MethodsThis prospective controlled trial randomized 161 patients with symptomatic paroxysmal atrial fibrillation undergoing cryoballoon pulmonary vein isolation to transseptal access with a commercially available transseptal system (radiofrequency needle plus stiff pigtail wire; RF + Pigtail group) versus conventional transseptal access (standard group). The primary outcome was time required for left atrial access. Secondary outcomes included failure of the assigned transseptal system, radiation exposure, and complications.ResultsThe median transseptal puncture time was significantly shorter using the radiofrequency needle plus stiff pigtail wire transseptal system compared with conventional transseptal (840 ± 323 vs. 956 ± 407 s, P = 0.0489). Compared to conventional transseptal puncture, fewer transseptal attempts were required (1.0 ± 0.5 RF applications vs. 1.3 ± 0.8 mechanical punctures, P = 0.0123) and the fluoroscopy time was significantly shorter (72.0 [IQR 48.0, 129.0] vs. 93.0 [IQR 60.0, 171.0] s, P = 0.0490) with the radiofrequency needle plus stiff pigtail wire transseptal system. Failure to achieve transseptal LA access with the assigned system was rarely observed (1.3% vs. 5.7%, P = 0.2192). There were no procedural complications observed with either system.ConclusionsThe use of a radiofrequency needle plus stiff pigtail wire resulted in shorter time to left atrial access and reduced fluoroscopy time compared to left atrial access using conventional transseptal equipment.Trial registrationClinicalTrials.gov identifier NCT03199703.

Percutaneous radiofrequency ablation of peripheral maxillary nerve: Description of new methodology.

Sir, Maxillary nerve is the second most affected branch in trigeminal neuralgia. It is treated with medical drugs like carbamazepine and baclofen. For long-term pain relief, chemical neurolysis and radiofrequency ablation (RFA) are commonly undertaken, of which RFA results in longer duration of pain relief, shorter onset and increased safety.[1] Chemical neurolysis of maxillary nerve can also result in serious complications.[2] RFA in chronic facial pain is being increasingly used with promising results.[3] We describe two patients where percutaneous RFA of peripheral maxillary nerve was undertaken without fluoroscopic/computed tomography (CT) guidance. A 60-year-old female, a diagnosed case of idiopathic trigeminal neuralgia presented with electric, sharp shooting pain of Numerical rating scale (NRS) score 6/10 in the maxillary area with frequent exacerbations for the last two years. She had inadequate pain relief with oral medications such as carbamazepine, pregabalin, baclofen and tramadol/acetaminophen. For long-term relief, RFA of maxillary nerve via percutaneous approach was planned in the block area of the out-patient department (OPD). Anaesthesia machine, resuscitation equipment, monitor and emergency drugs were available in the OPD block area. After taking consent, intravenous line was secured and monitors (pulse oximetry, non-invasive blood pressure, electrocardiography) were attached. Under aseptic precautions, a 22 G radiofrequency needle (Cosman, 10 cm length, active tip – 1 cm) was inserted via coronoid notch on right side, in supine and neutral head position, after infiltration of local anaesthesia. After hitting lateral pterygoid plate, needle was directed 2–3 mm beyond the pterygoid plate antero-superiorly towards the root of the nose [Figure 1]. To identify maxillary nerve, sensory stimulation (50 Hz, 1 mA) was used to elicit paraesthesia in maxillary area, achieved in first attempt at 0.3 mV. Motor involvement was ruled out by 2 Hz and 2 mA. 1 ml of 1% lignocaine was injected which caused paraesthesia in affected area and was followed by RFA of maxillary neve of 3 cycles at 65° for 60 s followed by injection dexamethasone 4 mg. This patient became pain-free for the next six months. All medications were reduced and tablet baclofen and tramadol were stopped.Figure 1: Infrazygomatic approach of maxillary nerve block (left); Radiofrequency generator for ablation of nerve (right)The second case was a 66-year-old male patient of idiopathic trigeminal neuralgia of one year duration with pain refractory to medical management. Maxillary nerve RFA was performed with similar methodology as above. Sensory stimulation was achieved at 0.4 mV and RFA was performed after excluding motor response. The patient was pain-free for the next eight months and his oral medications were considerably reduced. RFA of peripheral branches of the trigeminal nerve (infraorbital, supraorbital, mental and mandibular nerves) was found equally efficacious to RFA of gasserian ganglion through foramen ovale for trigeminal neuralgia; however, RFA of maxillary nerve was not undertaken in the study.[4] In the commonly practised percutaneous infrazygomatic maxillary nerve blockade,[5] a reliable block requires the patient to report paraesthesia by block needle. Electrical stimulation has reported higher sensitivity of nerve identification than paraesthesia[6] which was utilised for RFA of maxillary nerve via CT- guided percutaneous infrazygomatic approach through foramen rotundum.[7] However, this is invasive, has radiation hazards and requires special area. We propose RFA of maxillary nerve via percutaneous infrazygomatic approach and locating it by electrical stimulation. Added advantages are that it has no radiation hazards, is less invasive and it is an OPD block procedure. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Lumbar nerve root blocks using MRI - the effectiveness and safety of ultrasound/MRI fusion image guidance.

To compare the outcome of nerve root injection guided by ultrasound/MRI fusion with radiofrequency needle tracking (eTRAX©) and the same procedure undertaken by fluoroscopic guidance. This is a retrospective audit of anonymised clinical records from before and after a change in the imaging technique used to perform nerve root blocks.We studied 181 consecutive patients who had undergone a nerve root block, the first 124 guided by fluoroscopic technique and the next 57 guided by ultrasound/MRI fusion with radiofrequency needle guidance.Using pain diaries, we reviewed the outcome scores at 24 h and 2 weeks. We recorded the use of analgesia, the patient's satisfaction, complications and the duration of the procedures. Completed pain diaries were returned by 61% in the fluoroscopy group and 67% in the fusion imaging group.The visual analogue pain score was reduced at 24 h by 3.29 [standard deviation (SD) 2.35] for the fluoroscopy group and by 3.69 (SD 2.58) in the fusion group (p 0.399).At two weeks the pain reduction was 3.27 (SD 2.57) for the fluoroscopic group and 4.21 (SD 2.95) for the fusion group (p 0.083). There was no statistically significant difference between the groups.The patient's satisfaction scores were similar for both groups.The procedure by the two guidance methods took a similar time to perform.There were no serious complications in either group. One patient in the fusion-guided nerve root block group experienced paraesthesia in the nerve distribution for 2 h. Ultrasound/MRI fusion imaging with needle tracking is an effective alternative to fluoroscopic image-guided injection. Fusion imaging guidance provides the same outcome as fluoroscopic guidance.Fusion imaging guidance avoids the need for ionising radiation.

Evaluation of weight, caloric intake, and behavior of rats after bilateral ablation of the nucleus accumbens shell

Introduction: Deep brain stimulation and ablation of certain regions of the brain are being widely used in research aiming to link some region of the cortex with certain psychiatric disorders. The nucleus accumbens, for example, belonging to the basal ganglia, responsible for modulating the reward system and limbic-motor integration, according to studies, is related to the pathophysiology of alterations in neurotransmitters and neuronal connections in anorexia nervosa. Research in animals and humans reinforces this theory. Objective: To evaluate whether even in healthy rats, it is possible to observe changes in eating patterns and behavior that would justify such relationship. Materials and methods: A total of 24 female Wistar rats were randomly divided into experimental group (n=20) and control group (n=4). The rats in the experimental group underwent surgery with bilateral ablation of the nucleus accumbens shell using a stereotactic-guided radiofrequency needle. After surgery, the rats had their weights and caloric intake measured daily. Their behavior was empirically observed and then compared with that exhibited by the control group. Results: Regarding behavioral changes, it was observed an exaggerated increase in grooming, sniffing, searching/exploration, and avoidance/escape. Aggressiveness was present in only one animal of the experimental group. Regarding weight gain and caloric intake, a statistically significant relationship was found between them in relation to the time after the surgical intervention, when comparing the experimental and control groups. Discussion/Conclusion: In this study we investigated whether even in healthy rats, performing an inhibition – ablation of the Nucleus Accumbens – would cause an increase in caloric intake and consequently weight of the rats, and whether the procedure would cause changes in their behavior. From the results obtained we can infer that such assumption is true. Moreover, other research, both in humans and animals, support the data and the connection of the Nucleus Accumbens given by the reward system, to psychiatric disorders, in this case, anorexia nervosa. More investigations are necessary to further elucidate such interactions and consequences.

Effect of Radiofrequency Ablation with Interventional Therapy of Hepatic Artery on the Recurrence of Primary Liver Cancer and the Analysis of Influencing Factors.

Background The probability of liver cancer recurring in patients after surgery is a serious threat to liver cancer patients. Radiofrequency ablation is widely employed in liver cancer cases. We explored the therapeutic effects and influencing factors of radiofrequency ablation combined with hepatic artery intervention in patients with recurrence of primary liver cancer surgery. Methods 90 patients with primary liver cancer postoperative recurrence admitted to our hospital from January 2014 to February 2017 were selected as the research objects. The patients were randomly divided into the control group (n = 45) and combined treatment group (n = 45). The combined treatment group received radiofrequency ablation combined with hepatic artery interventional therapy, and the control group received hepatic artery interventional therapy. The short-term efficacy, AFP levels before and after treatment, and long-term survival results of the two groups were compared. Single-factor and multifactor analyses of the clinical information of the combined treatment group were carried out to find out the factors affecting the therapeutic effect of radiofrequency ablation combined with hepatic artery intervention on patients with recurrence of primary liver cancer. Results The total effective rate of short-term curative effect of the combined treatment group was higher than the control group, and there was a statistically significant difference existing (P < 0.05). After treatment, two groups of patients' AFP levels were greatly lower than before treatment, the AFP levels of the combined treatment group were significantly lower than the control group, and there was a statistically significant difference (P < 0.05). The survival rates of patients in the combined treatment group at the sixth month, the first year, and the second year after treatment were significantly higher than those of the control group, and there was a statistically significant difference (P < 0.05). The univariate results showed that, in the combined treatment group, there were statistically significant differences between the effective group and the ineffective group in tumor diameter, intact capsule, liver cirrhosis, intrahepatic spread, and tumor adjacent to large blood vessels (P < 0.05). The outcomes of multivariate analysis indicated that tumor diameter ≥ 3 cm, incomplete capsule, intrahepatic spread, and tumor adjacent to large blood vessels were risk factors for ineffective recurrence of patients with primary liver cancer after radiofrequency ablation combined with hepatic artery intervention (P < 0.05). Discussion. Tumor diameter ≥ 3 cm, incomplete capsule, intrahepatic spread, and tumor adjacent to large blood vessels are risk factors for the ineffectiveness of radiofrequency ablation combined with hepatic artery interventional therapy for patients with recurrence of primary liver cancer. It is necessary to increase the range of radiofrequency treatment, increase the temperature of the radiofrequency needle, and strengthen postoperative follow-up interventions based on the specific conditions of the patient's tumor.

Transseptal puncture without fluoroscopy using a radiofrequency needle: A case series.

The non-fluoroscopy approach with the use of a three-dimensional (3D) navigation system is increasingly recognized as a future technology in the treatment of arrhythmias. However, there are a limited number of articles published concerning transseptal puncture without the use of fluoroscopy. Presented in this paper is the first series of patients (n = 10) that have undergone transseptal puncture without the use of fluoroscopy under transesophageal echocardiography control using a radiofrequency transseptal needle and a 3D navigation system. All patients were treated without complications. In 6 patients, re-pulmonary vein isolation was performed. In 5 cases, linear ablation of the left atrium for treatment of left atrial macro re-entry tachycardia was provided. In 2 patients, focal atrial tachycardia was treated, 1 patient underwent cavo tricuspidal isthmus (CTI) ablation and 1 patient, re-CTI ablation. The ablation of complex fragmented atrial electrograms was done in 2 patients. In 1 case, right atrial macro re-entry tachycardia was treated. Transseptal puncture without using fluoroscopy is safe and effective when using a radiofrequency needle, a 3D navigation system and transesophageal echocardiography.

B-PO04-214 ATRIAL TRANS-SEPTOPLASTY DURING CONCOMITANT ATRIAL FIBRILLATION ABLATION AND LEFT ATRIAL APPENDAGE CLOSURE: A CASE REPORT

Transseptal catheterization (TC) is routine in electrophysiology and structural heart procedures. TC can be technically challenging due to a thick or scarred septum. Intracardiac echo (ICE) and Radiofrequency (RF) has helped in the success of TC. We report the first case of concomitant Atrial Fibrillation (AF) ablation with Left Atrial Appendage Closure (LAAC) with atrial trans-septoplasty (ATS). N/A A 63-year-old male with drug-refractory paroxysmal AF, CHADS Vasc Score of 6, and recurrent epistaxis presented for concomitant AF ablation and LAAC implant. ICE demonstrated a very thick septum of 1.2 cm without sparing of the fossa ovalis. Following transseptal (TS) puncture using RF needle, the TS sheath could not be advanced to the Left atrium (LA) despite different approaches including the use of a stiff pigtail wire in the LA, extra stiff wire in the right and left superior pulmonary vein (LSPV), and sequential dilation with progressively larger diameter long dilators. Successful ATS was performed under ICE and fluoroscopy guidance using a non-compliant 8 x 20 mm balloon over a stiff wire in the LSPV as shown in the figure, allowing access of a 14 Fr cryosheath into the left atrium. Pulmonary veins were successfully isolated using the cryoballoon. After the exchange of a Watchman (WM) sheath, a WM FLX device was successfully implanted under ICE and fluoroscopy guidance. ATS can be safely performed in difficult TC due to a thick septum. The balloon used for ATS can be selected based on the diameter of the transeptal sheath required to complete the procedure. Additional studies are needed to evaluate the long-term effects of this technique.

Transseptal puncture via a superior access as an alternative to the conventional femoral route

IntroductionCongenital heart disease (CHD) patients represent a challenge for ablation procedures and may require unusual procedural techniques. An example is the absence of femoral venous accesses that makes a conventional TSP approach impossible. ObjectiveWe report a series of 6 procedures in which transseptal puncture (TSP) was performed via the jugular vein approach using a radiofrequency (RF) needle visualized on the electroanatomical mapping (EAM) system. Methods and resultsAblation procedures for either atrial fibrillation and left-sided atrial tachycardia were performed in 3 patients (54-53-29years) with congenital disease and blocked femoral approach (interrupted inferior vena cava with azygos continuation (2 ​pts), bilaterally blocked femoral venous access due to previous interventions (1 ​pt)). Using the right jugular(n ​= ​5) and left jugular vein(n ​= ​1) we performed a single TSP using a combination of fluoroscopy and EAM guidance with 3D visualisation of the RF needle tip. The main difficulties encountered and solutions are described. In four procedures, remote magnetic navigation was subsequently used. Left atrial access was gained in all cases without complications. Overall procedural time was 373 [321–458] min, with a median fluoroscopy time of 16 [8–26] min and median radiation dose of 1442 [348–3007] μGym2. ConclusionTSP via superior access is feasible in patients with complex congenital cardiac anatomy. Pre-procedural imaging, EAM and the 3D visualisation of the transseptal needle are tools that greatly facilitate the procedural success.

Awake CT-guided percutaneous stylomastoid foramen puncture and radiofrequency ablation of facial nerve for treatment of hemifacial spasm.

Hemifacial spasm (HFS) is a debilitating neuromuscular disorder with limited treatment options. The current study describes a novel minimally invasive procedure that provided effective and sustained relief for patients with HFS. The authors provide a detailed description of the awake CT-guided percutaneous radiofrequency ablation (RFA) of the facial nerve for treatment of HFS, and they examine its clinical efficacy. This is the first time in the literature that this procedure has been applied and systematically analyzed for HFS. Patients with a history of HFS were recruited between August 2018 and April 2020. Those with a history of cerebellopontine lesions, coagulopathy, ongoing pregnancy, cardiac pacemaker or defibrillator implants, or who declined the procedure were excluded from the study. Fifty-three patients who met the study criteria were included and underwent awake CT-guided RFA. Under minimal sedation, a radiofrequency (RF) needle was used to reach the stylomastoid foramen on the affected side under CT guidance, and the facial nerve was localized using a low-frequency stimulation current. Patients were instructed to engage facial muscles as a proxy for motor monitoring during RFA. Ablation stopped when the patients' hemifacial contracture resolved. Patients were kept for inpatient monitoring for 24 hours postoperatively and were followed up monthly to monitor resolution of HFS and complications for up to 19 months. The average duration of the procedure was 32-34 minutes. Postoperatively, 91% of the patients (48/53) had complete resolution of HFS, whereas the remaining individuals had partial resolution. A total of 48 patients reported mild to moderate facial paralysis immediately post-RFA, but most resolved within 1 month. No other significant complication was observed during the study period. By the end of the study period, 5 patients had recurrence of mild HFS symptoms, whereas only 2 patients reported dissatisfaction with the treatment results. The authors report for the first time that awake CT-guided RFA of the facial nerve at the stylomastoid foramen is a minimally invasive procedure and can be an effective treatment option for HFS.

Step 2: under real-time ultrasonic monitoring, a Star RF fixed radiofrequency needle reaches the target position and standard radiofrequency treatment begins

Step 2: under real-time ultrasonic monitoring, a Star RF fixed radiofrequency needle reaches the target position and standard radiofrequency treatment begins

Frequency and average gray-level information for thermal ablation status in ultrasound B-Mode sequences

Abstract During thermal ablation in a target tissue the information about temperature is crucial for decision making of successful therapy. An observable temporal and spatial temperature propagation would give a visual feedback of irreversible cell damage of the target tissue. Potential temperature features in ultrasound (US) B-Mode image sequences during radiofrequency (RF) ablation in ex-vivo porcine liver were found and analysed. These features could help to detect the transition between reversible and irreversible damage of the ablated target tissue. Experimental RF ablations of ex-vivo porcine liver were imaged with US B-Mode imaging and image sequences were recorded. Temperature was simultaneously measured within the liver tissue around a bipolar RF needle electrode. In the B-Mode images, regions of interest (ROIs) around the centre of the measurement spots were analysed in post-processing using average gray-level (AVGL) compared against temperature. The pole of maximum energy level in the time-frequency domain of the AVGL changes was investigated in relation to the measured temperatures. Frequency shifts of the pole were observed which could be related to transitions between the states of tissue damage.

Initial Experience Using the Radiofrequency Needle Visualization on the Electroanatomical Mapping System for Transseptal Puncture.

Introduction Transseptal puncture (TSP) is a routine access route in patients with left-sided ablation substrates and is performed safely on fluoroscopy (+/− echocardiographic guidance). We report on our experience using a radiofrequency (RF) needle in an unselected group of patients to demonstrate safety and usefulness of direct tip visualization on the 3D electroanatomical mapping (EAM) system with specific emphasis on total radiation exposure. Methods and Results We retrospectively reviewed 42 consecutive left-sided ablation procedures with TSP performed using an RF needle guided by fluoroscopy and/or EAM visualization by a single operator. The procedures included atrial fibrillation (n = 33), atrial tachycardia (n = 8), and ventricular tachycardia (n = 1) ablations. Fourteen of 41 patients had congenital heart disease, including 9 patients with previous septal closure. Twenty-two patients had at least one previous TSP. All TSPs were performed successfully and without complications. The overall median fluoroscopy time amounted to 3.2 min and median exposure of 199.5 µGy∗m2. In a subgroup of patients (n = 27), the RF needle was visualized on the EAM system: median radiation time was 0.88 (interquartile range: 0–3.4) min and median exposure 33.5 [0–324.8] µGy∗m2. Conclusions TSP using an RF needle is an effective technique, also in congenital patients with artificial patch material and in normal patients with multiple previous TSPs. Moreover, the RF needle tip visualization on EAM allows a low (or even zero) fluoroscopy approach.

Department of Physical Medicine and Rehabilitation, University of Health Sciences, Fatih Sultan Mehmet Education and Training Hospital, Istanbul, Turkey

Background: Postherpetic neuralgia (PHN) occurs in 9% to 34% of herpes zoster (HZ) patients, and the incidence of PHN is positively correlated with age. A number of patients suffer from poor therapeutic effects or intolerable side effects and need to accept minimally invasive analgesia. Objectives: This study aimed to investigate the effects of spinal cord stimulation (SCS) and pulsed radiofrequency (PRF) on the treatment of elderly patients with HZ-related pain persisting beyond the acute phase. Study Design: A prospective, randomized-controlled trial. Setting: Research was conducted at the National Pain Management and Research Center, ChinaJapan Friendship Hospital (Beijing, China). Methods: We selected 63 patients aged over 50 years with zoster-related pain of 1 to 6 months onset. They were randomly divided into an SCS group and a PRF group. In the SCS group, the stimulus electrodes were placed in the affected spinal ganglion segment of the epidural space for 2 weeks. In the PRF group, the radiofrequency needle was percutaneously punctured in the affected dorsal root ganglion. The main outcome measures were the Numeric Rating Scale (NRS-11) score, response rate, and complete remission rate. The secondary endpoint was defined as the use of analgesics and calcium channel antagonists. Results: The NRS-11 score in the SCS group decreased to 2.90 ± 1.83 (1 week post operation) and 4.37 ± 2.43 (24 weeks post operation), while that in the PRF group decreased to 3.13 ± 1.78 and 4.23 ± 2.64, respectively (compared with baseline, P &lt; .001); there was no significant difference between the 2 groups (P &gt; .05) . The effective rate of pain management was in the range of 56.67% to 81.25%, and the complete pain relief rate ranged from 37% to 71%. The number of patients still using analgesics and calcium channel antagonists after operation were significantly less than those pre-operation (P &lt; .001). Univariate and multivariate logistic regression analyses showed that the operation method, age, gender, and course of disease did not affect surgical efficacy. Limitations: The main limitation of this study is that all the cases were from the same center. Conclusion: It therefore can be concluded that SCS and PRF can effectively relieve PHN. Key words: Spinal cord stimulation, pulsed radiofrequency, postherpetic neuralgia

Interventional Pain Medicine Practice in the UK and the USA: A Survey of 242 Pain Physicians

Pain medicine practices vary across different regions within a country and between countries. The objective of the survey was to study the variation in interventional pain medicine practices in the United Kingdom (UK) and the United States (US). A survey was designed in 2019 on Survey Monkey®. Pain physicians from the UK and the US were invited to respond. A total of 120 responses were received from pain physicians in the UK and 122 from the US. Twenty-six percent and 90% of pain physicians in the UK and US, respectively, are in full-time pain medicine practice. There was marked variation in the utilization of diagnostic medial branch blocks before performing radiofrequency denervation (RFD) between the UK and the US. In the UK, 42% of pain physicians, and 50% in the US, use a 20-gauge or a 22-gauge radiofrequency needle for lumbar RFD. Around 30% to 50% of pain physicians, both in the UK and the US, discontinued antithrombotic agents before medial branch blocks at all the spinal levels. Around 50% of pain physicians in the UK and US are stopping anticoagulants before lumbar and cervical RFD. Over 95% of UK and US respondents stopped antithrombotic agents for interlaminar and transforaminal epidural injections along the spine. At the lumbar level, 51% of pain physicians in the UK and 47% in the US use a particulate steroid for the initial lumbar transforaminal epidural injection (TFESI); and 4% and 14% in the UK and US, respectively, use a particulate steroid for initial cervical TFESI. Eight percent of pain physicians in the UK and 20% from the US would switch to a particulate steroid if the initial TFESI with a nonparticulate steroid did not provide satisfactory pain relief. Ten percent of pain physicians from the United Kingdom and 20% from the US believed that this switch provides better pain relief. Interventional pain physicians from the UK and the US were invited to respond. This may not reflect global practice. Our survey has highlighted the wide variation in interventional pain medicine practices both in the UK and the US. The relevant governing bodies in the UK and in the US should encourage clinicians to use at least an 18-gauge radiofrequency needle for RFD at the lumbar level. Discontinuing antithrombotic agents for the lumbar medial branch block is not justifiable. Pain physicians must discuss the advantages and disadvantages of using a nonparticulate over a particulate steroid preparation with the patient before performing TFESI as a standard procedure during the consenting process. Antithrombotic agents, epidural steroid, medial branch blocks, pain practice variations, particulate and nonparticulate steroids, radiofrequency denervation, spinal interventions.

Comparisons of Monopolar Lesion Volumes with Hypertonic Saline Solution in Radiofrequency Ablation: A Randomized, Double-Blind, Ex Vivo Study

Chronic degeneration of the zygapophyseal joints in the cervical or lumbar spine are common causes of axial back pain. Radiofrequency (RF) ablation is a treatment modality in the denervation of facet joint-related pain. Although multiple factors have been theorized to contribute to the size of the optimal RF lesion, the addition of hypertonic saline solution has been posited to create larger RF lesion sizes. This study compares lesion of 20-gauge RF monopolar probe using 2% lidocaine, 0.9% normal saline solution, and 3% saline solution administered through the RF needle prior to ablation, with subsequent lesion sizes recorded. Randomized, double-blinded, ex vivo study using clinically relevant conditions. Procedural laboratory in an academic institution. RF ablation lesions were reproduced in room temperature (21°C ± 2°C) chicken breast specimens with 20-gauge monopolar RF probes inserted. RF was applied for 90 seconds at 80°C after injection of 1 mL of either 2% lidocaine, 2% lidocaine and 0.9% normal saline solution in a 1:1 ratio, or 2% lidocaine and 3% saline solution in a 1:1 ratio. Tissues were dissected, measured, and ellipsoid volumes of burn calculated. Homogeneity of variances was assessed via the Bartlett's test, and heteroskedasticity with the studentized Breusch-Pagan test. One-way analysis of variance (ANOVA) (alpha of 0.05) was used to evaluate statistical significance between volume means across groups. When the null hypothesis of no difference in burn volume between samples could not be rejected, a predefined equivalence volume of ± 0.05 cm3 was used with Welch's 2 one-sided t-tests (TOST) with a Bonferroni adjusted alpha of 0.0167 to evaluate for null acceptance. The mean lesion volume for monopolar RF with 1 mL 2% lidocaine was 0.16 cm3. Monopolar RF with 1 mL 2% lidocaine + 0.9% normal saline solution had a mean lesion volume of 0.15 cm3, and treatment with 1 mL 2% lidocaine + 3% saline solution measured 0.17 cm3. ANOVA failed to reject the null, and TOST accepted as equivalent all 3 comparisons. In vivo anatomy and physiology of a human organism was not used for this study. Samples were not warmed to physiologic temperature. Randomization resulted in slightly unequal sample sizes, although all groups were of sufficient size that the central limit theorem should apply. Three commonly used solutions were found to have equivalent lesion sizes from monopolar probe RF ablation. Radiofrequency, ablation, lesion shape, lesion size, monopolar RF, hypertonic saline solution.

Perforating the GORE® CARDIOFORM septal occluder and atrial septal defect occluder to gain access to the left atrium.

Perforate the expanded polytetrafluoroethylene membrane of the GORE® CARDIOFORM Septal Occluder (GSO) and GORE® CARDIOFORM ASD Occluder (GCA) after implantation. Percutaneous transseptal access to the left atrium is necessary for many structural and electrophysiological procedures. The potential need to access the left atrium may influence decision-making for patent foramen ovale or atrial septal defect closure. Sixteen canines underwent implantation of equal number GSO or GCA devices. A transseptal crossing procedure was performed through the device 85 (±1) days postoccluder implantation. The crossing procedure was performed utilizing commercially available equipment: radiofrequency/SureFlex sheath and standard needle/Mullin's sheath. Progressive dilation of the perforation was performed to allow passage of a 12 French Mullin's sheath into the left atrium. Left atrial access was achieved in all cases. Postmortem analysis demonstrated passage through both occluder discs in all radiofrequency/SureFlex sheath cases (4 GSO, 4 GCA) and half of the standard needle/Mullin's sheath cases (3 GSO, 1 GCA). The remaining standard needle/Mullin's sheath cases demonstrated perforation through the right atrial disc but passage around the septal aspect of the left atrial disc, thus not perforating the left atrial disc. No acute embolic complications from the procedure were observed. Left atrial access may be achieved through the GSO or GCA devices after implantation and endothelialization. The combination of a radiofrequency needle and steerable sheath provides benefit over a standard needle and Mullin's sheath in accomplishing passage through both occluder discs.

Abstract No. 504 Ex vivo evaluation of the effect of multiple electrode radiofrequency needle tip convergence on size of ablation zone

Radiofrequency ablation (RFA) is an established therapy for treatment of malignancy in several organs, including the liver. One commonly used system, the Cool-tip Cluster Electrode, uses three parallel needles fixed in a triangular geometry. However, upon insertion, the final geometry of the needle tips can vary. In the case of converging needles, ablation volumes have been anecdotally observed to be smaller than expected. The study objective is to determine whether needle tip convergence significantly affects ablation zone in a bovine liver model. Cool-tip Cluster Electrodes were used to perform RFA in an ex vivo bovine liver using a 3D-printed guide to produce: no, partial or full convergence of the electrode needle tips. Ablation time was 12 minutes. Cone beam computed tomography scans were obtained to verify needle positions. Time to first roll off and period between roll-offs was recorded. Gross pathology was performed to estimate ablation zone volumes. Preliminary results from the initial pilot experiment found partial needle tip convergence decreased ablation zone volume by 6.13 cm3 (40.3%), time to first roll-off by 5.16 minutes (36.1%), and average time between roll-offs by 16 seconds (25.5%) compared to no convergence. Full convergence resulted in ablation zone volume decrease by 10.3 cm3 (67.7%), time to first roll-off decreased by 5.45 minutes (39.5%), and the average time between roll-offs decreased by 13 seconds (31.4%) compared to no convergence. Preliminary results suggest significant decrease in ablation volume and faster roll-off as the electrode tips increasingly converge. Further experiments are planned to test the study hypothesis with statistical significance. If confirmed, these results suggest confirmation of needle tip geometry prior to ablation should be performed clinically in order to ensure adequate ablation volumes when using Cool-tip Cluster electrodes.Tabled 1Distance Between Electrodes (mm)Diameter of Ablation Zone (cm)Ablation Volume (cm3)Time to First Roll-Off (min)Average Time Between Roll-Offs (sec)44.415.218.535133.49.083.373802.54.913.0835 Open table in a new tab

Nonsurgical Brow Lift With a Temperature-Controlled, Fractionated Radiofrequency Needle Device.

Nonsurgical Brow Lift With a Temperature-Controlled, Fractionated Radiofrequency Needle Device.

Computed Tomography (CT)-Guided Percutaneous Thoracic Sympathetic Chain Radiofrequency Thermocoagulation for Raynaud Disease.

BACKGROUND We introduce a minimally invasive technique for the treatment of Raynaud disease - CT-guided percutaneous thoracic sympathetic chain radiofrequency thermocoagulation. MATERIAL AND METHODS Under CT guidance, the radiofrequency needle was punctured from the upper edge of the costotransverse joint to the anterior superior edge of the 4th capitulum costae and the lateral parietal pleura. After sensorial (1.5 mA, 50 Hz) and motorial (1.5 mA, 2Hz) testing to determine that there was no nerve innervation zone with muscle numbness and twitches, radiofrequency coagulation was set at 95°C for 300 s. RESULTS A total of 17 patients were enrolled in the treatment group. All the patients underwent CT-guided percutaneous thoracic sympathetic chain puncture of the needles to the upper edge of the 4th capitulum costae on both sides. The perfusion index (PI) of the fingers began to rise 30 s after radiofrequency thermocoagulation, and the palm temperature (T) began to rise after 90 s. At the end of treatment, PI increased by an average of 4.6-fold, and the T average rose by 3.6°C. Postoperative cold-water stimulation testing could no longer induce Raynaud disease. Follow-up was conducted for 1 to 15 months. Two patients were found to have recurrence at 9 months and 13 months, respectively. CONCLUSIONS CT-guided percutaneous thoracic sympathetic nerve chain radiofrequency coagulation can effectively treat Raynaud disease.