Disrupting the epileptogenic network with stereoelectroencephalography-guided radiofrequency thermocoagulation

Stereoelectroencephalography-guided radiofrequency thermocoagulation (SEEG-guided RF-TC) is a treatment option for focal drug-resistant epilepsy. In previous studies, this technique has shown seizure reduction by ≥50% in 50% of patients at 1 year. However, the relationship between the location of the ablation within the epileptogenic network and clinical outcomes remains poorly understood. Seizure outcomes were analyzed for patients who underwent SEEG-guided RF-TC and across subgroups depending on the location of the ablation within the epileptogenic network, defined as SEEG sites involved in seizure generation and spread. Eighteen patients who had SEEG-guided RF-TC were included. SEEG-guided seizure-onset zone ablation (SEEG-guided SOZA) was performed in 12 patients, and SEEG-guided partial seizure-onset zone ablation (SEEG-guided P-SOZA) in 6 patients. The early spread was ablated in three SEEG-guided SOZA patients. Five patients had ablation of a lesion. The seizure freedom rate in the cohort ranged between 22% and 50%, and the responder rate between 67% and 85%. SEEG-guided SOZA demonstrated superior results for both outcomes compared to SEEG-guided P-SOZA at 6 months (seizure freedom p = .294, responder rate p = .014). Adding the early spread ablation to SEEG-guided SOZA did not increase seizure freedom rates but exhibited comparable effectiveness regarding responder rates, indicating a potential network disruption.

RELN gene-related drug-resistant epilepsy with periventricular nodular heterotopia treated with radiofrequency thermocoagulation: a case report

An increasing number of gene mutations associated with epilepsy have been identified, some linked to gray matter heterotopia-a common cause of drug-resistant epilepsy. Current research suggests that gene mutation-associated epilepsy should not be considered a contraindication for surgery in epilepsy patients. At present, stereoelectroencephalography-guided radiofrequency thermocoagulation is an important method to treat periventricular nodular heterotopia-associated drug-resistant epilepsy. We present a case of drug-resistant epilepsy, accompanied by periventricular nodular heterotopia and a heterozygous mutation of the RELN gene, successfully treated with radiofrequency thermocoagulation, resulting in a favorable outcome.

Virtual reality hypnosis prior to radiofrequency thermocoagulation for patients with chronic pain: an exploratory clinical trial

Background

The management of chronic pain may involve an array of tools, including radiofrequency thermocoagulation (Rf-Tc) of sensory nerve terminals. Like many other invasive procedures, Rf-Tc can generate anxiety in a lot of patients, either during the expectation of the procedure or in the course of it. Virtual reality hypnosis (VRH) is a promising tool for managing anxiety and pain in several situations, but its anxiolytic property has not been investigated in participants with chronic pain and going through a Rf-Tc procedure.

Objectives

The goal of this study was to evaluate the effectiveness of VRH for reducing self-assessed anxiety in participants with chronic pain, when received in preparation for Rf-Tc.

Materials and methods

This prospective, controlled trial was conducted in the Interdisciplinary Algology Centre of the University Hospital of Liège (Belgium). Participants were assigned to two groups: VRH or control (usual care). Assessment was carried-out at 4 time points: T0 (one week before Rf-Tc); T1 (pre-intervention, on the day of Rf-Tc); T2 (immediately after the VRH intervention outside of the Rf-Tc room); and T3 (right after Rf-Tc). Medical, sociodemographic data, anxiety trait and immersive tendencies were collected at T0. Anxiety state and pain intensity were assessed at each time points. Satisfaction was examined at T3.

Results

Forty-two participants were quasi-randomly assigned to the VRH or control group. No statistically significant interaction group by time was observed regarding all measured variables, including primary endpoint. However, a significant effect of time was found for anxiety and pain when considering both groups together, toward a progressive reduction.

Conclusion

In the context of our study, there appears to be no significant effect of VRH at reducing anxiety in participants with chronic pain undergoing Rf-Tc. Anxiety decreases along the procedure, while pain is attenuated by the local anesthetic infiltration of the Rf site. Our results suggest that the presence of a caregiver throughout the procedure might explain the progressive decrease in anxiety. Future randomized controlled trials are needed to precisely study the effectiveness of the VRH tool, and the possibility of using it as a complementary approach for anxiety during invasive procedures.

Comparison of initial percutaneous balloon compression versus radiofrequency thermocoagulation followed by percutaneous balloon compression in the treatment of trigeminal neuralgia

OBJECTIVES

There are a variety of minimally invasive interventional treatments for trigeminal neuralgia, and the efficacy evaluation is different. The preferred treatment scheme is still controversial. This study aims to investigate the differences in treatment effects between patients with primary trigeminal neuralgia (PTN) treated with percutaneous balloon compression (PBC) for the first intervention and patients with pain recurrence after radiofrequency thermocoagulation (RT) who then received PBC for PTN, and to offer clinicians and patients more scientifically grounded and precise treatment alternatives.

METHODS

We retrospectively analyzed 103 patients with PTN admitted to the Department of Pain Management of the Second Affiliated Hospital of Guangxi Medical University from January 2020 to December 2021, including 49 patients who received PBC for the first time (PBC group) and 54 patients who received PBC for pain recurrence after RT (RT+PBC group). General information, preoperative pain score, intraoperative oval foramen morphology, oval foramen area, balloon volume, duration of compression, and postoperative pain scores and pain recurrence at each time point on day 1 (T1), day 7 (T2), day 14 (T3), 1 month (T4), 3 months (T5), and 1 year (T6) were collected and recorded for both groups. The differences in treatment effect, complications and recurrence between the 2 groups were compared, and the related influencing factors were analyzed.

RESULTS

The differences of general information, preoperative pain scores, foramen ovale morphology, foramen ovale area, T1 to T3 pain scores between the 2 groups were not statistically different (all P>0.05). The balloon filling volume in the PBC group was smaller than that in the RT+PBC group, the pain scores at T4 to T6 and pain recurrence were better than those in the RT+PBC group (all P<0.05). Pain recurrence was positively correlated with pain scores of T2 to T6 (r=0.306, 0.482, 0.831, 0.876, 0.887, respectively; all P<0.01).

CONCLUSIONS

The choice of PBC for the first intervention in PTN patients is superior to the choice of PBC after pain recurrence after RT treatment in terms of treatment outcome and pain recurrence.

Stereoelectroencephalography-Guided Radiofrequency Thermocoagulation: Diagnostic and Therapeutic Implications

Despite recent medical therapeutic advances, approximately one third of patients do not attain seizure freedom with medications. This drug-resistant epilepsy population suffers from heightened morbidity and mortality. In appropriate patients, resective epilepsy surgery is far superior to continued medical therapy. Despite this efficacy, there remain drawbacks to traditional epilepsy surgery, such as the morbidity of open neurosurgical procedures as well as neuropsychological adverse effects. SEEG-guided Radiofrequency Thermocoagulation (SgRFTC) is a minimally invasive, electrophysiology-guided intervention with both diagnostic and therapeutic implications for drug-resistant epilepsy that offers a convenient adjunct or alternative to ablative and resective approaches. We review the international experience with this procedure, including methodologies, diagnostic benefit, therapeutic benefit, and safety considerations. We propose a framework in which SgRFTC may be incorporated into intracranial EEG evaluations alongside passive recording. Lastly, we discuss the potential role of SgRFTC in both delineating and reorganizing epilepsy networks.

Radiofrequency thermocoagulation for the treatment of trigeminal neuralgia associated with a focal pontine lesion: illustrative case

BACKGROUND

Trigeminal neuralgia (TN) associated with a focal pontine lesion is a rare but challenging condition. The origin of the lesion, which does not fulfill the diagnostic criteria for multiple sclerosis, remains disputable. Pain in such conditions is often refractory to treatment, including microvascular decompression.

OBSERVATIONS

A 36-year-old female presented with a 3.5-year history of shooting pain in the right V2 distribution triggered by talking and chewing. She became less responsive to high-dose carbamazepine over time. Magnetic resonance imaging (MRI) revealed no neurovascular compression but an elongated lesion hyperintense on T2-weighted imaging and T2- fluid-attenuated inversion recovery and hypointense and nonenhancing on T1-magnetization prepared rapid gradient-echo imaging without restricted diffusion, hemorrhage, or supposed malformation along the right pontine trigeminal pathway (PTP). Two other similar lesions were found in the corpus callosum and left thalamus. All lesions were stable compared to MRI data obtained 2 years before. Cerebrospinal fluid contained no oligoclonal bands. Pain attacks ceased with right-sided gasserian radiofrequency thermocoagulation (RFTC), and at the 6-month follow-up, there was no recurrence.

LESSONS

In patients with TN, preoperative neuroimaging should assess for brainstem lesions along the PTP. RFTC can be considered a treatment option in medication-refractory TN associated with a focal pontine lesion.

Stereo-electroencephalography-guided three-dimensional radiofrequency thermocoagulation for mesial temporal lobe epilepsy with hippocampal sclerosis: A retrospective study with long-term follow-up

OBJECTIVE

Stereo-electroencephalography-guided three-dimensional radiofrequency thermocoagulation (SEEG-3D RFTC) is a minimally invasive treatment for mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). This study aimed to investigate the long-term prognosis after SEEG-3D RFTC treatment in patients with MTLE-HS.

METHODS

This single-center retrospective study included 28 patients with MTLE-HS treated with SEEG-3D RFTC from January 2016 to May 2018. Postoperative curative effects were evaluated using the Engel classification, and the patients were followed up for 5 years.

RESULTS

The proportions of patients categorized as Engel I between 1 and 5 years after surgery were 72.41% (12 months after surgery), 67.86% (18 months after surgery), 62.07% (24 months after surgery), 50.00% (36 months after surgery), 42.86% (48 months after surgery), and 42.86% (60 months after surgery), respectively. Regarding long-term efficacy, based on the Engel classification, SEEG-3D RFTC showed room for improvement.

SIGNIFICANCE

This was the first study to evaluate the efficacy of SEEG-3D RFTC for MTLE-HS with long-term follow-up. SEEG-3D RFTC is a promising alternative for patients with MTLE-HS.

PLAIN LANGUAGE SUMMARY

This study explored the potential of stereoelectroencephalography-guided three-dimensional radiofrequency thermocoagulation, a minimally invasive approach, for treating medial temporal lobe epilepsy with hippocampal sclerosis. Involving 28 patients, the research tracked the treatment's success over five years using the Engel classification. Initial results were promising, with 72.41% of patients achieving the most favorable outcome (Engel I) at one year. While there was a gradual decrease in this proportion over time, 42.86% of patients maintained this positive outcome at five years, highlighting the treatment's potential for long-term efficacy.

Frameless robot-assisted stereoelectroencephalography-guided radiofrequency: methodology, results, complications and stereotactic application accuracy in pediatric hypothalamic hamartomas

Objective

We aimed to investigate the methodology, results, complications and stereotactic application accuracy of electrode implantation and its explanatory variables in stereoelectroencephalography-guided radiofrequency thermocoagulation (SEEG-RFTC) for pediatric hypothalamic hamartoma.

Methods

Children with hypothalamic hamartoma who underwent robot-assisted SEEG-RFTC between December 2017 and November 2021 were retrospectively analyzed. The methodology, seizure outcome, complications, in vivo accuracy of electrode implantation and its explanatory variables were analyzed.

Results

A total of 161 electrodes were implanted in 28 patients with 30 surgeries. Nine electrodes not following the planned trajectories due to intraoperative replanning were excluded, and the entry point and target point errors of 152 electrodes were statistically analyzed. The median entry point error was 0.87 mm (interquartile range, 0.50-1.41 mm), and the median target point error was 2.74 mm (interquartile range, 2.01-3.63 mm). Multifactor analysis showed that whether the electrode was bent (b = 2.16, p < 0.001), the length of the intracranial electrode (b = 0.02, p = 0.049), and the entry point error (b = 0.337, p = 0.017) had statistically significant effects on the target error. During follow-up (mean duration 31 months), 27 of 30 (90%) procedures were seizure-free. The implantation-related complication rate was 2.6% (4/152), and the major complication rate in all procedures was 6.7% (2/30).

Conclusion

Robot-assisted SEEG-RFTC is a safe, effective and accurate procedure for pediatric hypothalamic hamartoma. Explanatory variables significantly associated with the target point localization error at multivariate analysis include whether the intracranial electrode is bent, the intracranial electrode length and the entry point error.

A Case of Nerve Root Radiofrequency Thermocoagulation for Pain Due to Pleural Metastasis of Lung Cancer Leading to Improvement in the Patient's Quality of Life

Advances in medicine have made long-term survival of cancer patients possible. Hence, it is now necessary to consider how to approach common symptoms, such as cancer-related pain, in these patients. In this study, we describe a lung cancer patient in whom relief of intractable thoracic pain caused by pleural metastasis was achieved through thoracic radiofrequency thermocoagulation (RF), improving his quality of life (QOL). The patient was a man in his 70s with right upper lobe lung cancer, left 9th -11th rib metastasis, and left thoracic pain associated with parietal pleural metastasis. The patient experienced insomnia and weight loss due to poor appetite caused by opioid analgesics and inadequate pain control. Therefore, RF was performed as interventional treatment, resulting in a decrease in the numerical rating scale score from 10/10 to 2/10, and an improvement in QOL. In cases wherein long-term survival is expected, a long-term treatment plan for chronic cancer-related pain, which has a tendency to become persistent, becomes necessary. RF for the nerve roots might be a viable option for pain caused by pleural metastasis in cancer survivors.

Comparison of the safety and efficacy of radiofrequency thermocoagulation with percutaneous balloon compression for treating trigeminal neuralgia: a systematic review and meta-analysis

Objective

This study aimed to systematically assess the efficacy and complications of radiofrequency thermocoagulation (RFT) and percutaneous balloon compression (PBC) for treating trigeminal neuralgia (TN).

Methods

Chinese and English studies on RFT and PBC in the treatment of TN were systematically searched using CNKI, Wanfang Data, VIP, PubMed, EMBASE, Cochrane Library, and until December 31, 2022. Further, the literature was strictly screened using specific inclusion and exclusion criteria. The RevMan 5.4 software was used for data processing and meta-analysis.

Results

Overall, 16 studies with 3,326 patients were included. The results of meta-analysis revealed that no significant difference was present between the two groups in terms of the rate of efficacy immediately after surgery, 1 month after surgery, and 3 months after surgery (odds ratio [OR] = 0.73, 95% confidence interval [CI] 0.35-1.54, p = 0.41; OR = 0.41, 95% CI 0.13-1.32, p = 0.13; OR = 0.40, 95% CI 0.10-1.60, p = 0.20); however, at 12 months after surgery, the difference was statistically significant (OR = 0.27, 95% CI 0.10-0.75, p = 0.01). Notably, there was no significant difference in the postoperative sleep quality index between the two groups immediately after surgery and 1 month after surgery (SMD = -0.01, 95% CI -2.47 to 2.44, p = 0.99; SMD = 0.14, 95% CI -3.95 to 4.22, p = 0.95). Further, statistically significant differences were observed between the two groups in the incidence of postoperative masticatory muscle strength decline and oral herpes (OR = 0.37; 95% CI 0.21-0.63, p = 0.0003; OR = 0.25, 95% CI 0.10-0.61, p = 0.003). In addition, a statistically significant difference was found in the recurrence rate at 1-year follow-up (OR = 2.23, 95% CI 1.03-4.81, p = 0.04); however, no statistically significant differences were found in the recurrence rate at the 2-year follow-up (OR = 1.95, 95% CI 0.33-11.59, p = 0.46).

Conclusion

In the treatment of TN, both RFT and PBC can achieve good short-term efficacy, and no significant differences were noted between the outcomes of the two approaches. Compared with RFT, PBC may result in a lower pain score and recurrence rate in the medium and long terms, but it is a higher incidence of cold sores, and the decrease of masticatory muscle strength is more obvious.

The Comparison of General Characteristics and Early and Late Post-intervention Results in Patients With Trigeminal Neuralgia Secondary to Multiple Sclerosis and Idiopathic Trigeminal Neuralgia Treated With Radiofrequency Thermocoagulation

Aim The aim of this study was to investigate possible differences (in terms of demographic structure, disease history, complaints, clinical findings, early and late treatment outcomes, and complications) between patients with idiopathic trigeminal neuralgia (ITN) and trigeminal neuralgia (TN) secondary to multiple sclerosis (MS) who were admitted to our clinic and underwent radiofrequency (RF) thermocoagulation procedure. Materials and methods Patients who underwent percutaneous radiofrequency thermocoagulation with a diagnosis of trigeminal neuralgia by a single neurosurgeon in a single neurosurgery clinic between January 2005 and January 2020 were included in this study. Patients were divided into two groups: idiopathic trigeminal neuralgia and trigeminal neuralgia secondary to multiple sclerosis (MSTN) according to their diagnosis. In our study, 215 TN patients who underwent 286 procedures were included. These patients were categorized according to age, sex, involved side, pain localization, and pain history. Postoperative complications were determined after each intervention. The early and late results of all interventions were evaluated, and the results were compared between both groups. All results were statistically analyzed. Results Considering the age of the patients, the mean age of the idiopathic group was higher than the multiple sclerosis group (58.18>49.46). In terms of the side of pain, bilateral involvement was significantly more common in the MS secondary group (1.48%<30.77%). There was no significant difference between the early results of both groups. In terms of remission periods, the pain-free period in the MS secondary group was significantly shorter than in the idiopathic group (mean value in months, 30.87>23.81). Conclusion The radiofrequency thermocoagulation of the trigeminal nerve is a highly effective, low-complication, reproducible procedure for trigeminal neuralgia, but the search for ways to improve the efficacy of treatment in MS patients should continue.

How Far Has Radiofrequency Thermocoagulation Come Along as a Treatment Procedure in Treating Trigeminal Neuralgia Patients?

Trigeminal neuralgia (TN) refers to sudden shooting pain in areas innervated by trigeminal nerves originating from the Gasserian ganglion. Physicians initially manage it by prescribing drugs, such as carbamazepine. Surgical intervention is the next best option if patients do not respond to drug treatments. These procedures include microvascular decompression, rhizotomy, balloon compression, and gamma knife surgery. However, less optimal patient outcomes, recurrences, adverse effects, and high costs have necessitated alternative surgical interventions to treat such patients. Radiofrequency thermocoagulation (RFT) has emerged as a minimally invasive, safer, and effective surgical option in treating TN patients. Despite research showing RFT's safety and effectiveness, neurosurgical healthcare providers do not frequently use it to treat TN patients. Lack of universal standardized protocol, and minimal awareness of its efficacy in specific cohorts, such as geriatric patients, may lead to RFT underutilization. Hence, this review highlights RFT's advancement as a robust alternative to traditional surgical approaches in treating TN patients. In addition, it identifies RFT's areas of improvement and its safety and effectiveness in treating elderly TN patients. We followed the Systematic Reviews and Meta-Analyses guidelines for systematic reviews and conducted a literature search between July 2022 and March 2023. Our findings indicate that RFT has evolved significantly over the last decade and a half as a minimally invasive and effective treatment procedure for TN patients. It is more effective as a combined continuous and pulsed RFT than its other subtypes in treating primary TN patients. Moreover, RFT via a transverse puncture through the supraorbital foramen results in lesser inter- and post-procedural complications. Further, there is a slightly lesser incidence of post-procedural adverse effects and complications with RFT through the foramen rotundum. Besides, RFT, performed at a lower temperature of 65 degrees Celsius and a voltage between 64.51 and 79.29 volts, effectively provides pain relief and long-term patient satisfaction. RFT is safe and effective in patients over 60 with primary TN. Interestingly, it is also safe and effective in treating patients over 70 with poor fitness standards of Class II or higher. Despite these remarkable findings, there is still a substantial gap in the literature, specifically concerning the standardized protocol for temperature, voltage, and puncture methods of RFT. Despite the sufficient evidence of combined continuous and pulsed RFT's superiority in efficacy and safety, most researchers still utilize either pulsed or continuous RFT. Studies vary in not only these aspects but also the patient cohorts. For instance, most researchers focus solely on evaluating RFT's efficacy and safety in patients with primary TN, excluding a critical patient population suffering from secondary TN. Nevertheless, sufficient clinical evidence shows that RFT has come of age in treating primary TN patients. However, more extensive studies with large sample sizes of patients with primary and secondary TN with multiple trigeminal nerve affectation will significantly help standardize RFT protocol and its inclusion in the standard clinical practice in treating TN patients.

Puncture approaches and guidance techniques of radiofrequency thermocoagulation through foramen Ovale for primary trigeminal neuralgia: Systematic review and meta-analysis

Objective

Trigeminal neuralgia (TN) is one of the leading causes of facial pain and seriously affects patients' quality of life. Foramen ovale (FO) radiofrequency thermocoagulation is a classic approach for the treatment of TN that has failed pharmacological therapy. This study summarized the safety and efficacy of transforaminal radiofrequency thermocoagulation for TN by comparing puncture approaches or guidance techniques, thereby providing higher-quality clinical evidence.

Methods

Databases including PubMed, Embase, Cochrane Library, CNKI, and Wanfang were searched for relevant studies published before May 2022. Relevant data were extracted for analysis to compare methodological variables and clinical outcomes.

Results

This meta-analysis included 27 studies with a total of 1,897 patients. In terms of puncture approaches, FO had a significant advantage in reducing VAS at 12 months postoperatively (P = 0.019) and efficacy (P = 0.043). However, FO performed poorly on complications (P < 0.001), operation time (P < 0.001), and the number of needle adjustments (P < 0.001). Regarding the guidance techniques, the adjunctive use of guidance techniques could reduce patients' 6-month VAS (P < 0.001) and 12-month VAS (P < 0.001), improve the efficacy (P = 0.032), reduce recurrence rates (P = 0.001), shorten operation times (P < 0.001), decrease times of intraoperative fluoroscopy (P < 0.001), and improve the success of the first puncture (P < 0.001).

Conclusion

FO radiofrequency thermocoagulation has advantages in efficacy it can still better relieve the pain of patients 12 months postoperatively. However, FO has disadvantages in complications, recurrences, and operation time. The adjunctive use of guidance techniques has a positive effect on treatment efficacy and safety during FO radiofrequency thermocoagulation. However, the results still require large samples and high-quality randomized clinical trials to confirm.

Efficacy of Radiofrequency Thermocoagulation of the Thoracic Sympathetic Nerve versus Chemical Excision in Pain Caused by Raynaud's Disease

Objective

To investigate the effectiveness and safety of computed tomography (CT)-guided radiofrequency thermocoagulation (RFTC) of the thoracic sympathetic nerve versus chemical resection (CTS) for the treatment of pain caused by Raynaud's disease.

Methods

Patients who underwent CTS or thoracic sympathetic nerve RFTC between March 2012 and March 2021 were enrolled in this retrospective study. There were 28 cases in the alcohol group (Group A) and 44 in the radiofrequency group (Group R). Visual analog scores (VAS) were collected from patients at different time points, as well as preoperative and postoperative finger end perfusion index (PI) and hand temperature (T). The efficiency, postoperative recurrence rate, complications, and improvement in postoperative quality of life were observed in both groups.

Results

Pain scores at different follow-up times after surgery decreased in both groups compared to the preoperative period (P < 0.05). Postoperative T and PI were higher in both groups than preoperatively all (P < 0.05). The recurrence rate was higher in the R group than in the A group. Postoperative complications were observed in 13.6% and 25% of patients in groups R and A, respectively. Meanwhile, the postoperative quality of life improved in both groups, but the radiofrequency (RF) group was better than the alcohol group in terms of improvement in quality of life (P < 0.05).

Conclusion

Both CT-guided CTS and RFTC of the thoracic sympathetic nerve provided good treatment outcomes. However, the RF group was superior to the alcohol group in terms of complication rate and quality of life improvement.

Effectiveness and Safety of Radiofrequency Thermocoagulation Treatment Guided by Computed Tomography for Infraorbital Neuralgia Following Failed Conservative Treatment: A Retrospective Study

Purpose

To evaluate the effectiveness and safety of CT-guided radiofrequency thermocoagulation (RFT) for the treatment of infraorbital neuralgia following the failure of conservative management.

Patients and Methods

This was a single center, retrospective study which included 196 patients between the ages of 37 to 90 years, who suffered from infraorbital neuralgia, and had undergone CT-guided RFT treatment. The medical records of these patients were retrieved between January 7, 2015 and February 5, 2020, and the patients were followed up for 2 years. Follow-up outcomes included Numerical Rating Scale (NRS) scores, dosage of carbamazepine, time to take effect, status of recurrence and side effects. The effective rate was defined as the percentage of patients with postoperative NRS score reduction of >50%.

Results

The effective rates were 92.9%, 100%, 100%, 100%, 93.4% and 85.7% on the same day, week 1, month 1, month 6, year 1 and year 2 after RFT, respectively. After RFT, the postoperative NRS scores and dosage of carbamazepine were significantly reduced than those preoperatively (P < 0.05). The median time to take effect was zero day. Twenty-eight patients with recurrence underwent RFT again and achieved complete pain relief. All patients experienced numbness in the infraorbital nerve innervation area and the numbness scores gradually decreased over time.

Conclusion

CT-guided RFT treatment may be an effective and safe technique for pain relief in patients with infraorbital neuralgia following failed results from conservative treatment.

Long-term outcomes and predictors of percutaneous radiofrequency thermocoagulation of Gasserian ganglion for maxillary trigeminal neuralgia: a retrospective analysis of 1070 patients with minimum 2-year follow-up

OBJECTIVE

To estimate long-term efficacy and safety for maxillary trigeminal neuralgia (TN) using radiofrequency thermocoagulation (RFT) targeted on Gasserian ganglion, and to identify the factors which may influence outcomes after procedure.

METHODS

From 2006 to 2019, 1070 patients underwent RFT for the treatment of medically refractory maxillary TN was included. All patients were followed up for at least 2 years. Outcomes and complications were recorded and analysed. Logistic regression analysis was employed to identify risk factors of long-term pain recurrence. Prognostic value was calculated from receiver-operating characteristic curve (ROC).

RESULTS

Longitudinal analysis was taken place for 97 non-responders (9.1%) with ineffective pain relief, 253 responders (23.6%) with pain recurrence and 720 responders (67.3%) without pain recurrence. The median pain-free survival (PFS) was 112.0 months (95% CI: 107.5, 116.5). The pain-free rates were 89.9% (95% CI: 88.0-91.8%) at 1 year, 83.8% (95% CI: 81.5-86.1%) at 2 years, 75.4% (95% CI: 72.7-78.1%) at 5 years and 70.2% (95% CI: 67.4-73.0%) at 10 years. Atypical facial pain (HR = 5.373, 95% CI: 2.623-11.004, p < .001), previous facial numbness (HR = 5.224, 95% CI: 3.107-8.784, p < .001) and poor initial response to medication (HR = 3.185, 95% CI: 2.087-4.860, p < .001) were independently associated with long-term pain recurrence. Patients with prognostic index (PI) > 0.25 were identified as high-risk for recurrent TN (HR = 5.575, 95% CI: 3.991-7.788, p < .001). New and worsen facial hypoesthesia was recorded in 77.9% of patients corresponding with BNI score II-IV, and 18.7% reported improved sensation. Severe complication incidence including troublesome dysesthaesia, keratitis and masseter weakness was higher in 80 °C group.

CONCLUSIONS

Favourable outcomes were achieved in terms of long-term pain relief and complications rate after RFT for maxillary TN. Patients with typical facial pain, normal facial sensation, and good initial response to medications may have favourable long-term outcomes.Key messagesThis is a retrospective analysis of radiofrequency thermocoagulation (RFT) targeted on Gasserian ganglion for the treatment of maxillary trigeminal neuralgia (TN) during long-term follow-up. Recurrence-free survival among a large sample was assessed and risk factors associated with long-term pain recurrence was identified. It has been verified that inadvertent damage of ophthalmic and mandibular division causes ophthalmic and masticatory complications. Therefore, a more precise needle tip position and thermocoagulation using a relatively low temperature was recommended.

Radiofrequency thermocoagulation combined with doxorubicin injection for treatment of trigeminal neuralgia mandibular branch

OBJECTIVES

This study aimed to evaluate the clinical application value of 3D printed template-guided radiofrequency thermocoagulation combined with doxorubicin injection for the treatment of trigeminal neuralgia mandibular branch.

METHODS

A total of 50 patients with primary trigeminal neuralgia mandibular branch in the hospital from January 2019 to September 2020 were randomly divided into two groups: 3D printed template-guided radiofrequency thermocoagulation combined with doxorubicin injection was used as the research group (n=25), and 3D printed template guided radiofrequency thermocoagulation was used as the control group (n=25). Comparative analysis of visual analogue score (VAS) was conducted before and immediately after surgery and at 1, 3, 6, and 12 months after surgery. The Brisman efficacy evaluation criteria for trigeminal neuralgia was used to evaluate the therapeutic effect of each postoperative follow-up period, and postoperative complications were observed.

RESULTS

The VAS immediately after surgery and at 1, 3, 6, and 12 months after surgery in the two groups was significantly lower than that before surgery, with statistical significance (P<0.05). According to Brisman efficacy evaluation criteria for trigeminal neuralgia, no significant difference was found in the efficacy between the two groups at 1 and 3 months after surgery (P>0.05). At 6 and 12 months postoperatively, the effectiveness of the research group was higher than that of the control group, and the differences were statistically significant (P<0.05). In the research group, no recurrence occurred during the follow-up period, whereas in the control group, one, two, and four recurrences occurred 3, 6, and 12 months after surgery, respectively. No obvious complications were found in both groups.

CONCLUSIONS

3D printed template-guided radiofrequency thermocoagulation combined with doxorubicin injection for the treatment of trigeminal neuralgia mandibular branch could enhance the long-term curative effect and reduce the recurrence rate, thus worthy of clinical promotion and application.

Long-term Recurrence-free Survival and Complications of Percutaneous Balloon Compression and Radiofrequency Thermocoagulation of Gasserian Ganglion for Trigeminal Neuralgia:A Retrospective Study of 1313 Cases

OBJECTIVE

To estimate long-term recurrence, complications after percutaneous balloon compression (PBC) and radiofrequency thermocoagulation (RFT) of gasserian ganglion among a large sample of patients with trigeminal neuralgia (TN) during a long-term follow-up.

METHODS

A retrospective analysis of 1313 patients undergoing PBC or RFT for the treatment of TN was conducted from 2006 to 2020. Recurrence-free survival (RFS) was assessed by Kaplan-Meier method. Complications including facial numbness, corneal reflex decrease and masseter weakness were also estimated.

RESULTS

For patients who received first initial PBC and RFT, the median RFS was 130.1 months (95%CI: 124.4, 135.9) and 123.3 months (95%CI: 117.6, 128.9) in PBC and RFT group with log-rank p=0.108. The RFS rate was respectively 90.6% (95%CI: 88.1%-93.3%) and 91.4% (95%CI: 89.1%-93.7%) at 1 year, 84.6% (95%CI: 81.4%-87.8%) and 83.3% (95%CI: 80.3%-86.3%) at 3 years, 81.5% (95%CI: 78.1%-85.0%) and 78.6 % (95%CI: 75.2%-81.9%) at 5 years, 71.5% (95%CI: 67.5%-75.5%) and 64.8% (95%CI: 61.0%-68.7%) at 10 years in two groups. No significant difference was observed in facial numbness degree between two groups after procedure. Compared with PBC group, ophthalmic complication prevalence was higher in RFT group (9.6%) (p=0.001). However, masseter weakness incidence was lower (10.7%) than that in PBC group (24.0%) with p<0.001.

CONCLUSIONS

Patients with TN seemed to attain similar long-term benefit from PBC and RFT, especially in elderly. However, in order to reduce postoperative complications, PBC provided a safer and alternative for treating TN involving ophthalmic division, whereas RFT could be employed as a preferred regimen for maxillary and mandibular TN.

Chinese expert consensus on minimally invasive interventional treatment of trigeminal neuralgia

BACKGROUND AND PURPOSE

Trigeminal neuralgia is a common condition that is associated with severe pain, which seriously affects the quality of life of patients. When the efficacy of drugs is not satisfactory or adverse drug reactions cannot be tolerated, minimally invasive interventional therapy has become an important treatment because of its simple operation, low risk, high repeatability and low cost. In recent years, minimally invasive interventional treatments, such as radiofrequency thermocoagulation (RF) of the trigeminal nerve and percutaneous microcompression (PMC), have been widely used in the clinic to relieve severe pain in many patients, however, some related problems remain to be addressed. The Pain Association of the Chinese Medical Association organizes and compiles the consensus of Chinese experts to standardize the development of minimally invasive interventional treatment of trigeminal neuralgia to provide a basis for its clinical promotion and application.

MATERIALS AND METHODS

The Pain Association of the Chinese Medical Association organizes the Chinese experts to compile a consensus. With reference to the evidence-based medicine (OCEBM) system and the actual situation of the profession, the Consensus Development Committee adopts the nominal group method to adjust the recommended level.

RESULTS

Precise imaging positioning and guidance are the keys to ensuring the efficacy and safety of the procedures. RF and PMC are the most widely performed and effective treatments among minimally invasive interventional treatments for trigeminal neuralgia.

CONCLUSIONS

The pain degree of trigeminal neuralgia is severe, and a variety of minimally invasive intervention methods can effectively improve symptoms. Radiofrequency and percutaneous microcompression may be the first choice for minimally invasive interventional therapy.

Radiofrequency thermocoagulation for the treatment of trigeminal neuralgia

Although microvascular decompression (MVD) should be considered as the first-line treatment for classic trigeminal neuralgia (TN) owing to neurovascular compression of the trigeminal nerve, an increasing number of surgeons prefer radiofrequency thermocoagulation (RFT). RFT is a Gasserian ganglion-level ablative intervention that may achieve immediate pain relief for TN. It is used for emergency management when MVD is not suitable for the patient. As the gold surgical standard of classic trigeminal neuralgia, MVD has the advantage of longer efficacy. However, there are currently no high-quality controlled trials to evaluate the efficacy of MVD and RFT. For the present systematic review, the PubMed, Embase and Cochrane databases (all entries up until July 31, 2020) were searched to identify studies related to RFT in order to provide valuable information for clinical decision-making. The efficacy of the RFT method was evaluated in terms of the initial pain relief percentage, recurrence rate and follow-up time. Furthermore, the incidence rate of various postoperative complications was retrieved. RFT was used for a wider range of applications than MVD, including use for primary (owing to neurovascular compression of the trigeminal nerve), idiopathic and secondary (due to primary neurological diseases) TN, and provided a high rate of initial pain relief and long-term pain control. Although this method has several side effects, the incidence of complications could be reduced by precise cannulation. Furthermore, the complications that occurred were not permanent. Thus, RFT is a safe and effective minimally invasive method of pain relief for patients with TN.

Magnetoencephalography STOUT Method Adapted to Radiofrequency Thermocoagulation for MR-Negative Insular Epilepsy: A Case Report

Epilepsy is one of the most challenging neurologic diseases confronted by human society. Approximately 30–40% of the worldwide epilepsy patients are diagnosed with drug-resistant epilepsy and require pre-surgery evaluation. Magnetoencephalography (MEG) is a unique technology that provides optimal spatial-temporal resolution and has become a powerful non-invasive imaging modality that can localize the interictal spikes and guide the implantation of intracranial electrodes. Currently, the most widely used MEG source estimation method for clinical applications is equivalent current dipoles (ECD). However, ECD has difficulties in precisely locating deep sources such as insular lobe. In contrast to ECD, another MEG source estimation method named spatio-temporal unifying tomography (STOUT) with spatial sparsity has particular advantages in locating deep sources. In this case study, we recruited a 5 year-old female patient with insular lobe epilepsy and her seizure recurred in 1 year after receiving the radiofrequency thermocoagulation (RF-TC) therapy. The STOUT method was adopted to locate deep sources for identifying the epileptic foci in epilepsy evaluation. MEG STOUT method strongly supported a stereo-electroencephalographic (SEEG)-guided RF-TC operation, and the patient reported a satisfactory therapeutic effect. This case raises the possibility that STOUT method can be used particularly for the localization of deep sources, and successfully conducted RF-TC under the guidance of MEG STOUT results.

Role of High-Frequency Oscillation in Locating an Epileptogenic Zone for Radiofrequency Thermocoagulation

Radiofrequency thermocoagulation (RFTC) has been proposed as a first-line surgical treatment option for patients with drug-resistant focal epilepsy (DRE) that is associated with gray matter nodular heterotopia (GMNH). Excellent results on seizures have been reported following unilateral RFTC performed on ictal high-frequency-discharge, fast-rhythm, and low-voltage initiation areas. Complex cases (GMNH plus other malformations of cortical development) do not have good outcomes with RFTC. Yet, there is little research studying the effect of high-frequency oscillation in locating epileptogenic zones for thermocoagulation on unilateral, DRE with bilateral GMNH. We present a case of DRE with bilateral GMNH, treated using RFTC on unilateral GMNH and the overlying cortex, guided by stereotactic electroencephalogram (SEGG), and followed up for 69 months. Twenty-four-hour EGG recordings, seizure frequency, post-RFTC MRI, and neuropsychological tests were performed once yearly. To date, this patient is seizure-free, the electroencephalogram is normal, neuropsychological problems have not been found, and the trace of RFTC has been clearly identified on MRI. His dosage of antiepileptic medication has, furthermore, been significantly reduced. It is concluded that RFTC on unilateral DRE with bilateral GMNH may achieve good long-term effects, lasting up to, and perhaps longer than, 69 months. Ictal high-frequency oscillation (fast ripple) inside the heterotopia and the overlying cortex may be the key to this successful effect.

Robotic Guided Bilateral Anterior Cingulate Radiofrequency Ablation for Obsessive-Compulsive Disorder

Background

Bilateral anterior cingulotomy (BAC) constitutes the most commonly performed procedure for treatment of refractory OCD. Evolution of stereotactic procedures has rekindled the interest in the effective management of refractory psychiatric disorders, especially OCD with utmost safety and excellent outcomes.

Objective

The aim of this study was to demonstrate the technique of performing BAC under robotic guidance using radiofrequency ablation with an operative video.

Procedure

A 23-year-old gentleman diagnosed with symptoms of OCD for a duration of 8 years and was refractory to conventional therapy. The trajectories for BAC were planned on the robotic platform (ROSA, Zimmer-Biomet, Warsaw, Indiana, USA). The target point was selected on the anterior cingulate, approximately 2 cms posterior to the anterior most point of the frontal horn, 2-3 mm above the corpus callosum and 7 mm lateral to the midline. Pre coronal (1 cm anterior and 3 cms lateral to midline) holes of 2.5 mm diameter were made using pneumatic handheld drill. Radiofrequency (RF) thermocoagulation of the anterior cingulum was performed using an RF probe of 2.2 mm diameter and 4 mm uninsulated tip under robotic guidance after confirming the position with intraoperative O-arm imaging bilaterally.

Results

The surgery was uneventful and the patient had a significant improvement following surgery, with the Yale Brown Obsessive Compulsive Scale of 18 at 1 year follow-up compared to the preoperative score of 36.

Conclusion

Robotic-guided BAC is a safe and effective technique for the treatment of drug-refractory OCD. Intraoperative O arm CT augments the precision of the lesions created.

Technical Aspects of SEEG and Its Interpretation in the Delineation of the Epileptogenic Zone

Stereo-electroencephalography (SEEG) has gained global popularity in recent years. In Japan, a country in which invasive studies using subdural electrodes (SDEs) have been the mainstream, SEEG has been approved for insurance coverage in 2020 and is expected to gain in popularity. Some concepts supporting SEEG methodology are fundamentally different from that of SDE studies. Clinicians interested in utilizing SEEG in their practice should be aware of those aspects in which they differ. Success in utilizing the SEEG methodology relies heavily on the construction of an a priori hypothesis regarding the putative seizure onset zone (SOZ) and propagation. This article covers the technical and theoretical aspects of SEEG, including the surgical techniques and precautions, hypothesis construction, and the interpretation of the recording, all with the aim of providing an introductory guide to SEEG.

One-Stage High-Density Focal Stereo-Array SEEG-Guided Radiofrequency Thermocoagulation for the Treatment of Pediatric Giant Hypothalamic Hamartomas

Background: Giant hypothalamic hamartomas (HHs) are extremely rare lesions, for which the treatment is challenging. While minimally invasive treatments such as radiofrequency thermal coagulation and laser ablation have improved seizure outcomes, multiple operations are often required. This study investigated the value of one-stage stereo-array radiofrequency thermocoagulation based on stereotactic electroencephalography (SEEG) for pediatric giant HHs.

Methods: We analyzed the clinical data of six patients with giant HHs (masses with a maximum diameter >30 mm) who underwent stereotactic electrode implantation between November 2017 and April 2019. After a multidisciplinary discussion, we designed a high-density focal stereo-array electrode implantation strategy. SEEG-guided bipolar coagulations were performed between two contiguous contacts of the same electrode, or between two adjacent contacts of different electrodes.

Results: Among the six patients, three were male and three were female, with an average age of 5.08 ± 4.73 years (range, 1.4–12 years); the average follow-up duration was 20.17 ± 5.49 months. One patient had previously undergone open surgery. Four patients had gelastic seizures, one had gelastic and tonic seizures, and one had gelastic and generalized tonic-clonic seizures. The number of implanted electrodes ranged from 3 to 7, with an average of 5.33. One patient had transient diabetes insipidus after the operation, and no child had fever or new hormone metabolisms disorder after surgery. Four patients had Engel I classification outcomes (free from disabling seizures), and two patients had Engel II classification outcomes.

Conclusion: Although the exploration of epileptic activity and the extent of ablation are limited by the number of SEEG electrodes for the complete disconnection. One-stage high-density focal stereo-array SEEG-guided radiofrequency was safe and effective for treating pediatric giant HH patients. It can be an alternative method to treat giant HHs where LITT is unavailable.

Factors Associated With Long-Term Risk of Recurrence After Percutaneous Radiofrequency Thermocoagulation of the Gasserian Ganglion for Patients With Trigeminal Neuralgia Involving the Ophthalmic Division: A Retrospective Study

OBJECTIVE

To evaluate risk factors associated with recurrence after radiofrequency thermocoagulation (RFT) of the gasserian ganglion among patients with ophthalmic trigeminal neuralgia (TN) and prognostic factors in terms of recurrence-free survival (RFS) during a long-term follow-up.

METHODS

From January 2005 to December 2017, 300 patients with ophthalmic TN underwent RFT. A retrospective analysis of 14-year outcomes was performed. Kaplan-Meier analysis was used for RFS after the procedure. Univariate and multivariate Cox regression analyses were performed to identify risk factors for pain recurrence.

RESULTS

The initial effective rate of RFT for ophthalmic TN was 92%. The mean follow-up time was 77.38 ± 43.24 months. The cumulative probability of RFS was 86.94% at 1 year, 80.03% at 2 years, 77.27% at 3 years, 74.01% at 5 years, and 59.92% at 10 years after RFT. The mean duration of RFS was 114.67 months (95% confidence interval [CI] 106.27 to 123.06 months). In multivariate analysis, atypical pain (hazard ratio [HR] = 2.831, 95% CI 1.759 to 4.554, P < 0.001) and mild facial hypesthesia (HR = 2.540, 95% CI 1.309 to 4.931, P = 0.006) before RFT were independently associated with pain recurrence. Patients with a prognostic index (PI) > 1.27 were at high risk for pain recurrence. Major complications included troublesome dysesthesia (0.7%), keratitis (10.9%), diplopia (0.4%), facial paresthesia (6.2%), and masseter weakness (12.7%). Masseter weakness was more common in patients with V3 branch involvement. Three patients lost their sight due to keratitis.

CONCLUSION

Our study investigated long-term outcomes and complications of RFT for ophthalmic TN. Patients at high risk for pain recurrence were identified, which might provide a basis for clinical decision making before RFT.

Comparing the Safety and Effectiveness of Radiofrequency Thermocoagulation on Genicular Nerve, Intraarticular Pulsed Radiofrequency with Steroid Injection in the Pain Management of Knee Osteoarthritis

BACKGROUND

Knee osteoarthritis (KOA) is characterized by the clinical symptoms of chronic knee pain and knee dysfunction, leading to disability and influencing the quality of life in severe cases. Radiofrequency treatment is a new method to reduce KOA-related pain and partially improve knee joint dysfunction without adverse effect.

OBJECTIVE

The present study aimed to assess the treatment efficacy of radiofrequency thermocoagulation on the genicular nerve (RFTGN) and intraarticular pulsed radiofrequency (IAPRF) for KOA.

STUDY DESIGN

Retrospective comparative study design.

SETTING

This study took place at Shengjing Hospital of China Medical University.

METHOD

KOA patients were randomly assigned to the RFTGN, IAPRF, and intraarticular steroid injection (IAS) groups. All procedures were performed under the guidance of computed tomography (CT). The observation indicators of this study were the numeric rating scale (NRS), Oxford knee scale (OKS), and perceived global effect (GPE). The time points for the assessment were 1-week, 1-month, 3-months, and 6-months after the treatment.

RESULTS

The postoperative NRS scores in the 3 groups decreased significantly at all the observation time points as compared to the pretreatment scores (P < 0.05). For the patients in the IAS group, the analgesic effect was in a rebound trend, which was the best at 1-week posttreatment, and was close to the preoperative level at 6-months posttreatment. The short-term (1 week or 1 month) analgesic effect of the RFTGN group was better than that of the IAPRF group, and was similar in the long-term (3 or 6 months). The long-term analgesic effect of RFTGN and IAPRF groups was better than that of IAS group. The results of the OKS score were similar to the NRS score. The RFTGN group showed markedly improved knee function in the long-term than the IAPRF and IAS groups. The short-term treatment satisfaction was similar in each group, and some differences were detected between the groups with respect to long-term treatment satisfaction.

LIMITATION

This study was a single-center retrospective study with a relatively small sample cohort and short follow-up periodCONCLUSION: Both RFTGN and IAPRF could alleviate the knee joint pain and improve the knee joint dysfunction; however, the treatment efficacy of RFTGN was better than that of IAPRF.

Stereo-crossed ablation guided by stereoelectroencephalography for epilepsy: comprehensive coagulations via a network of multi-electrodes

Background:

Introducing multiple different stereoelectroencephalography electrodes in a three-dimensional (3D) network to create a 3D-lesioning field or stereo-crossed radiofrequency thermocoagulation (scRF-TC) might create larger lesioning size; however, this has not been quantified to date. This study aimed to quantify the configurations essential for scRF-TC.

Methods:

By using polyacrylamide gel (PAG), we investigated the effect of electrode conformation (angled/parallel/multiple edges) and electrode distance of creating an electrode network. Volume, time, and temperature were analyzed quantitatively with magnetic resonance imaging, video analysis, and machine learning. A network of electrodes to the pathological left area 47 was created in a patient; the seizure outcome and coverage range were further observed.

Results:

After the compatibility test between the PAG and brain tissue, the sufficient distance of contacts (from different electrodes) for confluent lesioning was 7 mm with the PAG. Connection to the lesioning field could be achieved even with a different arrangement of electrodes. One contact could achieve at least six connections with different peripheral contacts. Coagulation with a network of electrodes can create more significant lesioning sizes, 1.81–2.12 times those of the classic approaches. The confluent lesioning field created by scRF-TC had a volume of 38.7 cm³; the low metabolic area was adequately covered. The representative patient was free of seizures throughout the 12-month follow up.

Conclusion:

Lesioning with electrodes in a network manner is practical for adequate 3D coverage. A secondary craniotomy could be potentially prevented by combining both monitoring and a large volume of lesions.

Treatment of Supraorbital Neuralgia Using Ultrasound-Guided Radiofrequency Thermocoagulation of the Supraorbital Nerve: A Retrospective Study

Purpose

There is no standard clinical treatment protocol for supraorbital neuralgia patients who respond poorly to conservative treatment. Radiofrequency thermocoagulation, a neurologically damaging procedure, is a treatment for supraorbital neuralgia. However, assessments of its long-term efficacy are lacking. Thus, this study aimed to evaluate the long-term efficacy and safety of ultrasound-guided radiofrequency thermocoagulation for treating supraorbital neuralgia.

Patients and Methods

We retrospectively reviewed our clinical database for supraorbital neuralgia patients who underwent an ultrasound-guided radiofrequency thermocoagulation procedure. Demographic data and baseline characteristics, time of onset, postoperative pain intensity, time of recurrence, subsequent treatment, complications and side effects were collected and analysed. The Kaplan-Meier estimator was used to determine recurrence-free survival.

Results

A total of 53 supraorbital neuralgia patients were included in this study. All patients experienced complete pain relief within one month. The median follow-up time of the 53 patients was 36.0 months (IQR, 12.0-72.0 months). A total of 13 patients experienced pain recurrence, with a median recurrence-free time of 97 months according to the Kaplan-Meier estimator. The cumulative proportion of recurrence-free survival was 96.2% at 12 months, 88.4% at 24 months, 82.7% at 36 months, 70.0% at 48 months, 66.3% at 60 months, and 49.7% at 97 months. All but one patient with recurrent pain underwent a second or third radiofrequency thermocoagulation procedure and achieved complete pain relief. Numbness of supraorbital nerve innervation occurred in all patients. However, the numbness scores gradually decreased over time.

Conclusion

Ultrasound-guided radiofrequency thermocoagulation is a safe, effective treatment for supraorbital neuralgia patients who respond poorly to conservative treatments. These patients attained excellent long-term pain relief with a gradual reduction in numbness.

A case report of May-Thurner syndrome induced by anterior lumbar disc herniation: Novel treatment with radiofrequency thermocoagulation

RATIONALE

Lumbar degeneration-related May-Thurner syndrome (dMTS) is characterized by venous compression induced by degenerated lower lumbar structures. Treatment strategies for May-Thurner syndrome (MTS) include clearing the thrombus and correcting venous compression. Despite having different etiological factors from other MTS types, treatments for dMTS are similar, including endovascular angioplasty and continuous anticoagulation therapies. Thus, a particular treatment was designed herein to focus on compressive lumbar structures instead of intravenous management.

PATIENT CONCERNS

A 59-year-old female patient with dMTS, which was induced by inferior vena cava (IVC) stenosis compressed by L4-5 anterior disc herniation.

DIAGNOSIS

The patient was diagnosed with IVC stenosis and L4-5 lumbar disc herniation based on abdominal computed tomography, ultrasound, and lumbar magnetic resonance imaging findings.

INTERVENTIONS

Radiofrequency thermocoagulation (RF) was applied to the patient to decrease the compression caused by anterior disc herniation.

OUTCOMES

After surgery, the patient's swelling started to improve within 5 hours and completely diminished after 48 hours. Postsurgical abdominal ultrasound showed that her IVC patency increased by 20%. On follow-up, her leg symptoms did not recur at 12 months after surgery.

LESSONS

We provided a novel idea in the treatment of dMTS, in which we shifted the treatment focus from endovascular patency restoration to extravascular decompression. Our case proved that RF was effective in treating dMTS, which is a complementary treatment modality to angioplasty.

Comparison of the short-term outcomes after low-temperature plasma radiofrequency ablation (coblation) in the Gasserian ganglion for the treatment of idiopathic trigeminal neuralgia

Background: Low-temperature plasma radiofrequency ablation (coblation) is a relatively novel technique with promising applications in neuropathic pain. A nerve stimulator was modified and connected to a plasma knife head to solve the problem of accessing the Gasserian ganglion for treatment of trigeminal neuralgia (TN). Objective: To compare the therapeutic effects and short-term outcomes of coblation vs radiofrequency thermocoagulation for the treatment of primary TN. Methods: This was a retrospective cohort study of 217 inpatients who had undergone surgical treatment for primary TN between September 2017 and June 2018 at the Xuanwu Hospital, Capital Medical University. The patients were grouped according to the procedure they selected after an informed comprehensive discussion with their surgeon: the coblation group and the radiofrequency group. Pain, numbness, and muscle atrophy were evaluated before surgery, on the day of surgery, and at 3 days, 5 days, and 3 months after surgery. Results: In the coblation and radiofrequency groups, the pain relief rates were 74.7% and 85.5% on day 1 (P=0.066), 85.3% and 97.3% on day 3 (P=0.003), and 97.7% and 88.2% at 3 months (P=0.134). At 3 months after surgery, 69.3% of the patients in the coblation group and 42.7% in the radiofrequency group had no pain (P<0.001). The multivariable analysis showed that the risk of numbness in the coblation group was independently lower than in the radiofrequency group at 3 months after surgery and (OR=0.243, 95%CI: 0.122-0.484, P<0.001). Three months after the surgery, no recurrence was found in both of the coblation group and the radiofrequency group. Postoperative pain score ≥4 points was considered as a sign of failure this series at 3 months after surgery. The failure rate in coblation group is 2.7% (n=2) and a radiofrequency group is 4.5% (n=5), but there was no statistical difference between the two groups (P=0.703). Conclusion: Coblation could reduce the risk of postoperative numbness in patients with primary TN.

Therapeutic efficacy and safety of radiofrequency ablation for the treatment of trigeminal neuralgia: a systematic review and meta-analysis

Objective

The objective of this study was to summarize the effectiveness and safety of trigeminal neuralgia (TN) treatment via different radiofrequency approaches such as continuous radiofrequency (CRF), pulsed radiofrequency (PRF), and combined CRF and pulsed radiofrequency (CCPRF) treatments, thus providing high-quality clinical evidence for TN treatment.

Methods

A series of databases were searched for relevant articles published between January 1998 and April 2018. The modified Jadad scale was referred to evaluate the methodological quality of the included studies. Data were extracted independently, and the outcome and safety of different routes, temperatures, and guidance used in CRF, PRF, and CCPRF were compared. Meta-analysis and publication bias were calculated using Review Manager software.

Results

In total, 34 studies involving 3,558 participants were included. With regard to TN treatment, PRF had no difference in cured rate in comparison with CRF, while CRF was more effective than CCPRF (P<0.05). The comparison of complication rates showed that PRF and CCPRF were safer. For puncture guidance via CRF, three-dimensional-printed template was more accurate in success rate at first puncture than computed tomography guidance (P<0.05). For puncture route, foramen rotundum (FR) or pterygopalatine fossa (PPF) route had no significance in efficiency rate via CRF in comparison with foramen oval (FO) route, but PPF and FR routes were safer. For CRF treatment, low temperature (68°C-70°C) compared with high temperature (71°C-75°C) had no effect. Moreover, higher temperature (66°C-80°C) had a greater effect compared with lower temperature (55°C-65°C) on TN treatment (P<0.05), while the safety of which was decreasing.

Conclusion

CCPRF could achieve a greater effect and safety on TN treatment. FR and FO routes in TN puncture treatment via CRF are safer. Medium temperature range is better for CRF therapy, and higher temperature is recommended in PRF, especially for the elders. Further international multicenter trials are needed to confirm the evidence.

Impar Ganglion Block with Combination of Neurolysis Drugs and Radiofrequency Thermocoagulation for Perineal Pain

Since it was first introduced, a variety of modification techniques to block the impar ganglion appear such as transsacrococcygeal ligament technique, sacrococcygeal transdiscal approach, paramedian approach, and a two-needle technique using fluoroscopy or computed tomography scan. For therapeutic purposes, a combination of steroid and local anesthetic, neurolysis agents such as alcohol, phenol, cryolesioning, and heat lesioning using radiofrequency thermocoagulation could be used. Here, we reported a successful outcome in treating chronic perineal pain in a 65-year-old patient using combination of neurolysis agent which was alcohol 96% and radiofrequency thermocoagulation.

Bi-modal radiofrequency treatment for coexisting neuralgia and neuropathy in adjacent divisions of the trigeminal nerve

Trigeminal neuralgia and deafferentation neuropathic pain, or trigeminal neuropathy, are different symptomatologies, rarely reported to present together. The case of a 65-year-old gentleman suffering from trigeminal neuralgia of the maxillary and mandibular division is reported. He first underwent an infraorbital neurectomy that was complicated by deafferentation neuropathic pain, whilst his mandibular neuralgia continued. He was treated successfully for both the neuropathic and neuralgic symptoms in the same session using ultra-extended euthermic pulsed radiofrequency treatment for the maxillary division (V2) and radiofrequency thermocoagulation for the mandibular division (V3). This report is novel in describing the use of dual modalities in the same session for two distinct coexisting clinical entities in two different divisions of the same cranial nerve. The use of ultra-extended pulsed radiofrequency treatment for neuropathic pain in this case is also unique. Nearly 2years after the procedure, the patient continues to have complete pain relief.

Radiofrequency Thermocoagulation of the Ganglion Impar for Coccydynia Management: Long-Term Effects

OBJECTIVE

To investigate the short- and long-term effects of ganglion impar radiofrequency thermocoagulation (RFT) treatment in patients with chronic coccydynia.

METHODS

We retrospectively analyzed the medical records of patients who underwent RFT of the ganglion impar between 2009 and 2011. Pain intensity visual numeric scale (VNS) scores and Euroqol 5D (EQ-5D) index scores were recorded pre-intervention and post-intervention at the first, sixth, and twelfth months. The differences between pre-procedural VNS scores and post-procedural VNS scores at the first, sixth, and twelfth months were evaluated. The success of the intervention was recorded as the percentage difference between the pre-intervention VNS scores and post-intervention VNS scores at the first, sixth, and twelfth months.

RESULTS

The mean age of the patients, including 11 females (55%) and 8 males (45%), was 48.7 ± 14.3 years. The average follow-up duration was 17.3 ± 2.9 months. Statistically significant differences were observed between the pre- and post-procedure VNS scores (P < 0.0001). Improvements in VNS scores were correlated with improvements in EQ-5D index scores. Mid-term (sixth month) and long-term (twelfth month) evaluations after the intervention revealed that 67.4% and 61.1% of the patients had successful outcomes, respectively.

CONCLUSION

Our data suggested that RFT of the ganglion impar in patients with chronic coccydynia resulted in effective outcomes, and patients who responded to RFT had significantly lower post-RFT pain scores.

Comparison of coblation annuloplasty and radiofrequency thermocoagulation for treatment of lumbar discogenic pain

This study aimed to compare the effectiveness and safety of coblation annuloplasty and radiofrequency thermocoagulation for lumbar discogenic pain.Patients who suffered from lumbar discogenic pain and underwent coblation annuloplasty and radiofrequency thermocoagulation surgery were included. A questionnaire, including the visual analo scale (VAS), MacNab criteria, pain relief rate, and any complications due to surgery, was completed by the patients with the help of a trained volunteer who was blinded to the study. Data were collected at 1 week, and 1, 3, 6, and 12 months after surgery. Significant pain relief was defined as postoperative pain relief ≥50% compared with the preoperative state. Any complications during or after surgery were also recorded.A total of 122 patients were included; 37 patients were lost in the follow-up and 85 were evaluated. Among these, 45 patients underwent coblation annuloplasty (CA group, n = 45) and 40 underwent radiofrequency thermocoagulation procedures (RF group, n = 40).VAS pain scores were decreased at 1 week and 1, 3, 6, and 12 months postoperatively compared with preoperation in both groups (P < .05). The CA group had significantly lower VAS scores at 6 and 12 months of follow-up than did the RF group (P < .05). According to the modified MacNab criteria, the proportions of patients with excellent and/or good results at 3, 6, and 12 months of follow-up were significantly higher in the CA group compared with the RF group (P < .05).Only 2 patients reported soreness at the needle insertion site in the CA group. However, 3 patients had soreness at the needle insertion site, 3 had increased intensity of low back pain, 1 had intracranial hypotension, and 2 had new numbness in the leg and foot in the RF group. At the 1-year follow-up, this numbness was present all of the time. No major complications occurred in the CA group.Our study suggests that CA is a more effective and safe minimally invasive procedure than RF for treating lumbar discogenic pain.

Selective Percutaneous Controlled Radiofrequency Thermocoagulation of the Gasserian Ganglion To Control Facial Pain Due to Medication-Related Osteonecrosis of the Jaw

BACKGROUND

Medication-related osteonecrosis of the jaw (MRONJ) is an important complication in patients treated with antiresorptive agents such as bisphosphonates and the receptor activator of nuclear factor κB ligand inhibitor (denosumab). Treatment of MRONJ is extremely difficult, which makes it a distressing long-term complication.

OBJECTIVES

We report a case of intractable facial pain due to MRONJ that was successfully controlled with selective percutaneous controlled radiofrequency thermocoagulation of the Gasserian ganglion.

SETTING

A 68-year-old woman with breast cancer was diagnosed as having MRONJ. She was very distressed because of jaw pain and infections secondary to MRONJ. Her quality of life (QOL) was severely decreased. Since alleviation of the MRONJ could not be expected within the patient's life expectancy, it was decided to investigate the usefulness of selective percutaneous controlled radiofrequency thermocoagulation of the Gasserian ganglion to control the pain.

RESULTS

After the procedure, the anesthesia was obtained in the distribution of the third branch of the trigeminal nerve, and the pain completely disappeared. Although hypoesthesia was provoked as a complication, it was tolerated by the patient and she was very satisfied. Up to the time of death, there was no recurrence of pain or worsening of the MRONJ.

DISCUSSION

This procedure is a common technique for treating trigeminal neuralgia. Its effect is immediate and long lasting, although it provokes hypoesthesia in treated division, and it is also suited for cancer patients in terminal stage. This case suggests that the procedure was useful for improving the patient's QOL.

Percutaneous trigeminal ganglion radiofrequency thermocoagulation alleviates anxiety and depression disorders in patients with classic trigeminal neuralgia: A cohort study

Trigeminal neuralgia (TN) is a neurological condition that presents as excruciating facial pain. Depression and anxiety are commonly associated with TN; however, anxiety and depression disorders in patients with TN and the effects of the various therapeutic strategies for TN on these disorders are not well studied.To evaluate depression and anxiety in patients with trigeminal neuralgia (TN), identify factors that predict their occurrence and study the effect of the percutaneous trigeminal ganglion radiofrequency thermocoagulation (PRT) procedure for alleviating pain on depression and anxiety.Patients with classic TN, who received PRT treatment, were consecutively recruited between October 2014 and October 2015. Severity of pain was determined using the visual analogue scale (VAS) score. Beck Depression Inventory-II (BDI) and Beck anxiety Inventory (BAI) were used to evaluate depression and anxiety disorders pre- and post-PRT. Medical, demographic, and psychosocial backgrounds were also assessed as predictive factors. A BDI score of ≥14 represented depression and BAI score of ≥45 represented anxiety. VAS, BDI, and BAI scores were collected at the time of admission and on the day of discharge.Of the 167 patients who participated in the study, 121 (72.5%) had depression and 34 (20.4%) suffered anxiety. Pre-PRT procedure, female sex, age >50 years, ineffective treatment, and high pain intensity (VAS ≥7) predicted the development of depression and anxiety. Post-PRT procedure, all patients who experienced pain relief also reported amelioration of depression and anxiety.A considerable percentage of patients with TN developed depression and anxiety. Patients who were female, older than 50 years, or suffered from failure treatment and severe pain (VAS>7), were at higher risk of depression and anxiety development. Complete alleviation of pain by using surgical PRT could immediately attenuate depressive and anxiety disorders associated with TN.

Percutaneous radiofrequency thermocoagulation for trigeminal neuralgia using neuronavigation-guided puncture from a mandibular angle

Percutaneous radiofrequency thermocoagulation (RFT) of the Gasserian ganglion is an effective treatment for primary trigeminal neuralgia (pTN). Currently Hartel anterior approach is the most commonly used method to access the Gasserian ganglion. However, this approach is associated with high recurrence rate and technical difficulties in certain patients with foramen ovale (FO) anatomical variations. In the present study, we assessed the feasibility of accessing the Gasserian ganglion through the FO from a mandibular angle under computed tomography (CT) and neuronavigation guidance.A total of 108 patients with TN were randomly divided into 2 groups (Group G and Group H) using a random number table. In Group H, Hartel anterior approach was used to puncture the FO; whereas in Group G, a percutaneous puncture through a mandibular angle was used to reach the FO. In both groups, procedures were guided by CT imaging and neuronavigation. The success rates, therapeutic effects, complications, and recurrence rates of the 2 groups were compared.The puncture success rates in Group H and Group G were 52/54 (96.30%) and 49/54 (90.74%), respectively (P = 0.24). The 2 procedural failures in Group H were rescued by using submandibular trajectory, and the 5 failures in Group G were successfully reapproached by Hartel method. Therapeutic effects as measured by Barrow Neurological Institute (BNI) pain scale (P = 0.03) and quality of life (QOL) scores (P = 0.04) were significantly better in Group G than those in Group H at 36 months posttreatment. Hematoma developed in 1/54 (1.85%) cases in Group H, and no cases of hematoma were observed in Group G (P = 0.33). In Group H, RFT resulted in injury to the unintended trigeminal nerve branches and motor fibers in 27/52 (51.92%) cases; in Group G, it resulted in the same type of injury in 7/49 cases (14.29%) (P < 0.01). In Group H, the 24- and 36-month recurrence rates were 12/51 (23.53%) and 20/51 (39.22%), respectively; in Group G, these recurrence rates were 7/49 (12.24%) and 9/49 (16.33%, P = 0.03), respectively.CT- and neuronavigation-guided puncture from a mandibular angle through the FO into the Gasserian ganglion can be safely and effectively used to deliver RFT for the treatment of pTN. This method may represent a viable option to treat TN in addition to Hartel approach.

Application of radiofrequency thermocoagulation combined with adriamycin injection in dorsal root ganglia for controlling refractory pain induced by rib metastasis of lung cancer (a STROBE-compliant article)

This study aimed to observe the therapeutic effects and adverse reactions of radiofrequency thermocoagulation combined with adriamycin injection in dorsal root ganglia on lung cancer rib metastasis-related refractory pain which has no response to conventional therapy.This study contained 27 patients with lung cancer rib metastasis-related moderate or severe pain which had no response to conventional therapy. Under computed tomography (CT)-guidance, radiofrequency puncture need reached the corresponding intervertebral foramens to ensure needle point near dorsal root ganglia (DRG) by sensory and motor stimulation tests, and then radiofrequency thermocoagulation was performed on each corresponding DRG followed by injection of 0.5 to 1 mL of adriamycin (0.5%). The conditions of pain and complications were observed before management and 3 days, 1 month, and 3 months after management, respectively.Numerical rating scale (NRS) scores and dosage of morphine were all significantly decreased after management as compared with those before management (all P < 0.01). Although the number of patients with chest wall numbness was significantly increased after management as compared with that before management (all P < 0.01), the degree of chest wall numbness was tolerable. There were no statistical differences between before and after management in nausea and vomiting, and constipation.CT-guided radiofrequency thermocoagulation combined with adriamycin injection in DRG can effectively control lung cancer rib metastasis-related pain which has no response to conventional therapy. This combinatory treatment regimen is featured by better therapeutic effects and a few complications, so it is worthy of being recommended in clinical application.

Treatment of bilateral idiopathic trigeminal neuralgia by radiofrequency thermocoagulation at different temperatures

Radiofrequency thermocoagulation (RFT) is an effective treatment for trigeminal neuralgia, but consensus regarding an optimal treatment temperature is lacking. While treatment temperatures ranging from 60°C to 95°C have been reported, RFT at too high a temperature is often followed by serious complications, and comparative evaluations of RFT at different temperatures in a single study are rare.This current prospective cohort study was to compare immediate and long-term outcomes of RFT at varying temperatures in patients with bilateral idiopathic trigeminal neuralgia (ITN) of maxillary division of trigeminal nerve (V2), mandibular division of trigeminal nerve (V3), and V2+V3, including pain relief, complications, recurrence rate, and patient satisfaction. From May 2011 to April 2016, 62 consecutive patients with bilateral ITN of V2, V3, and V2+V3 were enrolled in the study. These patients underwent bilateral RFT at 68°C and 75°C, respectively, using the same RF parameters. Side-to-side results, including pain relief, complications, and patient satisfaction, were compared during a 5-year follow-up period.Overall pain relief was satisfactory after RFT. The rate of pain relief after treatment at 75°C was slightly higher than at 68°C (P > 0.05). The pain-free rate was 95.1% at 75°C and 93.5% at 68°C at 1 year, 84.3% and 78.1% at 3 years, and 80.7% and 74.4% at 5 years. There were 10 and 13 cases of recurrence, respectively, and 6 cases of bilateral recurrence. The incidence and severity of complications were greater at 75°C (P < 0.05) than at 68°C, and therefore the patient satisfaction at the higher temperature was lower (P < 0.05).Patients with bilateral ITN who underwent RFT at different temperatures had consistent pain relief after RFT at both 75°C and 68°C, but there were fewer and less severe complications at 68°C, which was accompanied by greater patient satisfaction. This suggests that RFT at lower temperatures may be preferable, and that a temperature of 68°C can be recommended.

The optimal radiofrequency temperature in radiofrequency thermocoagulation for idiopathic trigeminal neuralgia: A cohort study

OBJECTIVE

Our previous study evaluated the effectiveness and safety of radiofrequency thermocoagulation (RFT) of trigeminal gasserian ganglion for idiopathic trigeminal neuralgia (ITN). The aim of this study was to evaluate the optimal radiofrequency temperature of computed tomography (CT)-guided RFT for treatment of ITN.

METHODS

A retrospective study of patients with ITN treated with a single CT-guided RFT procedure between January 2002 and December 2013. Patients were divided into ≤75 °C, 75 °C, and ≥80 °C groups according to the highest radiofrequency temperature used. Pain relief was graded from poor to excellent, and facial numbness/dysesthesia from I (absent) to IV (most severe).

RESULTS

A total of 1161 RFT procedures were undertaken in the 1137 patients. The mean follow-up time was 46 ± 31 months. There were no significant differences in the rate of excellent pain relief according to the radiofrequency temperature used. However, more patients experienced with no facial numbness or facial numbness gradually resolved and those patients treated at 75 °C had a lower rate of grade IV facial numbness/dysesthesia than other groups.

CONCLUSIONS

The optimal radiofrequency temperature to maximize pain relief and minimize facial numbness or dysesthesia may be 75 °C, but this requires confirmation.

Radiofrequency thermocoagulation for V2/V3 idiopathic trigeminal neuralgia: effect of treatment temperatures on long-term clinical outcomes: A Cohort Study

Radiofrequency thermocoagulation (RFT) is widely used to treat trigeminal neuralgia (TN); however, the optimal temperature at which RFT is most efficacious remains under much debate. Thus, the aim of the present study was to determine the lowest temperature at which morbidity could be minimized and patient outcomes maximized.A multivariate analysis was used to study 1354 patients who underwent computed tomography (CT)-guided RFT for V2/V3 idiopathic trigeminal neuralgia (ITN) during from June 2006 to May 2015. RFT was carried out at 62, 65, and 68°C, while keeping all other RF parameters the same. This was a prospective cohort study, in which we assessed intra- and postoperative complications, pain relief, and long-term health-related quality of life (HRQoL).The intraoperative and in-hospital complications of patients were mainly facial hematoma, mouth and external auditory meatus penetration, nausea, vomiting, dizziness, and headache, which were all treated symptomatically. In long-term follow-up, patients with pain relief (defined as no pain and no required drug intervention) at 62, 65, and 68°C accounted for 94.2%, 98.3%, and 98.8% (at discharge); 83.8%, 90.1%, and 91.4% (at 1 year); 66.7%, 80.5%, and 88.2% (at 3 years); 59.0%, 64.3%, and 77.2% (at 5 years); 48.7%, 57.8%, and 72.3% (at 7 years); 40.6%, 53.7%, and 60.3% (at 9 years), respectively. The number of patients with facial numbness, masticatory atonia, or corneal hypoesthesia was increased with the elevation of temperature, but these complications were all mild. No blindness, deafness, intracranial hemorrhage, or death as a result of the surgical intervention occurred in any patients. SF-36 scores showed highest HRQoL in the group treated at 68°C, followed by the 65 and 62°C groups, respectively.Our results demonstrate that 68°C is a good choice for RFT of V2/V3 ITN. The alternative option is 65 or 62°C for RFT to minimize the occurrence of complications including facial numbness, yet which often yields a higher recurrence rate.

Laser speckle imaging to improve clinical outcomes for patients with trigeminal neuralgia undergoing radiofrequency thermocoagulation

OBJECTIVE

Percutaneous treatments for trigeminal neuralgia are safe, simple, and effective for achieving good pain control. Procedural risks could be minimized by using noninvasive imaging techniques to improve the placement of the radiofrequency thermocoagulation probe into the trigeminal ganglion. Positioning of a probe is crucial to maximize pain relief and to minimize unwanted side effects, such as denervation in unaffected areas. This investigation examined the use of laser speckle imaging during probe placement in an animal model.

METHODS

This preclinical safety study used nonhuman primates, Macaca nemestrina (pigtail monkeys), to examine whether real-time imaging of blood flow in the face during the positioning of a coagulation probe could monitor the location and guide the positioning of the probe within the trigeminal ganglion.

RESULTS

Data from 6 experiments in 3 pigtail monkeys support the hypothesis that laser imaging is safe and improves the accuracy of probe placement.

CONCLUSIONS

Noninvasive laser speckle imaging can be performed safely in nonhuman primates. Because improved probe placement may reduce morbidity associated with percutaneous rhizotomies, efficacy trials of laser speckle imaging should be conducted in humans.

Application of Antidromic Conduction Monitoring in Ganglion Radiofrequency Thermocoagulation for Locating Trigeminal Branches in Trigeminal Neuralgia

OBJECTIVE

The aim of this study was to investigate whether antidromic conduction monitoring (ACM) can be utilized to map the trigeminal system under sedation as a potential substitute for subjective paresthesia description (SPD) during percutaneous ganglion radiofrequency thermocoagulation (PGRT).

METHODS

Eighty-two patients with 152 pain divisions of trigeminal neuralgia (TN) were treated by computed tomography (CT)-guided PGRT. After the puncture needle entered the foramen ovale (FO), sensory and motor stimulation were applied to locate the pain division. And the corresponding voltage values were recorded by patients' SPD. In the following, the proper location was certified by ACM. The corresponding earliest waves and voltage values in the identified trigeminal branch were also recorded to outline a comparison between two methods.

RESULTS

The correlation of ACM and patients' SPD with voltage at ≤ 0.5 V was statistically significant (P < 0.05, r = 0.159; Spearman's rank correlation analysis). Although ACM and SPD showed weak correlation, as their interclass correlation coefficient was significant (F = 1.868, P < 0.01) with coefficient of internal consistency. Moreover, the two methods had consistency. Kruskal-Wallis test showed that ophthalmic (V1), maxillary (V2), and mandibular (V3) divisions had significant differences for test sensitivity (H = 15.945, P < 0.01). For comparison of sensitivities with ACM, V3 was most sensitive followed by V2 and then V1.

CONCLUSION

ACM could potentially substitute for SPD of the paresthesias intra-operatively, enabling greater specificity and eliminating the need to interrupt the administration of anesthetic. These improvements would increase patient satisfaction and practitioner efficiency and accuracy.

Efficacy and safety of a new robot-assisted stereotactic system for radiofrequency thermocoagulation in patients with temporal lobe epilepsy

The aim of the present study was to evaluate the efficacy and safety of a newly developed robot-assisted frameless stereotactic system for deep electrode implantation and radiofrequency thermocoagulation (RFTC). Deep-electrode implantation was performed in the bilateral mesial temporal lobes of seven patients. Following the implantation of the deep electrodes through the monitored designed path, the epileptogenic zones were determined with the assistance of a robot system. Deep electrode electroencephalograms were recorded prior to and following RFTC. Treatment outcomes were evaluated by computed tomography scans and Engel classification criteria. The procedure was well tolerated by all patients with no patients suffered from severe permanent complications. After follow-ups for 34–62 months, four patients achieved Engel class I, including three patients with Ia classification, two patients were classified as Engel class IVa and one patient was classified as Engel class IVc. Therefore, robot-assisted frameless stereotaxy for deep electrode implantation and RFTC is indicated to be a safe and effective method that may be used effectively in clinical practice.