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PURPOSE OF REVIEW: Glioblastoma remains resistant to most conventional treatments. Despite scientific advances in the past three decades, there has been a dearth of effective new treatments. New approaches to drug delivery and clinical trial design are needed. RECENT FINDINGS: We discuss how the blood-brain barrier and tumor microenvironment pose challenges for development of effective therapies for glioblastoma. Next, we discuss treatments in development that aim to overcome these barriers, including novel drug designs such as nanoparticles and antibody-drug conjugates, novel methods of drug delivery, including convection-enhanced and intra-arterial delivery, and novel methods to enhance drug penetration, such as blood-brain barrier disruption by focused ultrasound and laser interstitial thermal therapy. Lastly, we address future opportunities, positing combination therapy as the best strategy for effective treatment, neoadjuvant and window-of-opportunity approaches to simultaneously enhance therapeutic effectiveness with interrogation of on-treatment biologic endpoints, and adaptive platform and basket trials as imperative for future trial design. New approaches to GBM treatment should account for the blood-brain barrier and immunosuppression by improving drug delivery, combining treatments, and integrating novel clinical trial designs.

Glioblastoma (GB), the most common malignant brain tumour, has a poor prognosis despite advances in treatment. Standard management involves surgery followed by chemoradiotherapy. MRI-guided laser interstitial thermal therapy (LITT) is a minimally invasive technique that may offer an option for select patients with specific clinical profiles. While preclinical studies suggest that LITT could disrupt the blood-brain barrier (BBB) to enhance drug delivery, this has yet to be definitively demonstrated in clinical settings. Adhering to the PRISMA guidelines, various databases were searched until March 2024. Eligible studies focused on LITT for supratentorial GB in adults and evaluated its safety and efficacy. Data extraction covered various study characteristics, and statistical analysis was performed using the OpenMeta Analyst software. Quality assessment was performed using the Newcastle-Ottawa Scale. Fifteen studies were analyzed, mainly employing the Neuroblate–Monteris system in the US, as retrospective single-centre trials. Treatment involved LITT in 239 patients with tumours typically in deep-seated areas. Median OS ranged from 4.9 to 32.3 months, and PFS from two to 5.9 months. Most patients received adjuvant therapy, primarily radiation and temozolomide. While LITT showed efficacy in improving OS (10.21, 95% CI 9.05–11.37), PFS (3.94, 95% CI 3.20–4.69), and tumor volume reduction (18.23, 95% CI 14.591–21.860), complications odd-ration(OR) = 0.336 (95% CI, 0.188–0.484) and mortality rates OR = 0.033 (95% CI, 0.009–0.058 were notable. LITT shows promise for treating both newly diagnosed and recurrent GB cases in non-surgical candidates, linked to improved OS, PFS, reduced tumor volume, and shorter hospital stays. However, higher complication and mortality rates were noted, emphasising the need for additional well-designed prospective multicentre trials. [ABSTRACT FROM AUTHOR]

Purpose: Spinal laser interstitial thermal therapy (sLITT) is a less invasive alternative to surgery for metastatic epidural spinal cord compression. Here, we analyze outcomes of patients treated with sLITT either in conjunction with radiotherapy or as a standalone salvage therapy. Methods: We included patients with thoracic vertebral metastatic cord compression treated with sLITT. Outcomes included freedom from local failure (FFLF) and overall survival (OS). Factors associated with FFLF were identified with univariable and multivariable analyses via a Cox proportional hazards model. Results: Between 2013–2022, 129 patients received sLITT to 144 vertebral segments; 69% were radiotherapy naïve, 81% were radioresistant histologies, and 74% were centered in the vertebral body. Median age was 61 years. Pre-sLITT Bilsky score was 3 in 28%, 2 in 33%, and 1c in 37%. Radiotherapy was delivered in conjunction with sLITT for 80% of cases, including 68% that received stereotactic radiotherapy, at a median of 5 days after sLITT. Median follow-up was 9.1 months. One-year FFLF and OS was 80% and 78%, respectively. On multivariable analysis, variables independently associated with adverse FFLF included paraspinal/foraminal disease location (p = 0.001), and post-sLITT imaging Bilsky score of 2 (p = 0.073) or 3 (p = 0.011). Prior radiotherapy, technique of radiotherapy, and time between radiotherapy and sLITT were not associated with FFLF. Conclusion: sLITT with radiotherapy is an effective minimally invasive treatment approach for thoracic metastatic epidural spinal cord compression. Early treatment response may serve as a prognostic imaging biomarker. [ABSTRACT FROM AUTHOR]

Background: The surgical treatment of brain tumors has developed over time, offering customized strategies for patients and their specific lesions. One of the most recent advances in pediatric neuro-oncological surgery is laser interstitial thermal therapy (LITT). However, its effectiveness and indications are still being evaluated. The aim of this work is to review the current literature on LITT for pediatric low-grade gliomas (pLGG) and evaluate our initial results in this context. Methods: We retrospectively reviewed our pediatric neurosurgery database for patients who received LITT treatment between November 2019 and December 2023. We collected data on the indications for LITT, technical issues during the procedure, and clinical and radiological follow-up. Results: Three patients underwent 5 LITT procedures for pLGG. The lesion was thalamo-peduncular in one patient, cingulate in one, and deep parietal in one patient. Two patients had a previous open resection done and were diagnosed with pLGG. One patient underwent a stereotaxic biopsy during the LITT procedure that was non-diagnostic. The same patient underwent a later open resection of the tumor in the cingulate gyrus. There were no surgical complications and all patients were discharged home on the first post-operative day. The follow-up period was between 20 and 40 months. Radiological follow-up showed a progressive reduction of the tumor in patients with LGG. Conclusion: Laser interstitial thermal therapy is a minimally invasive treatment that shows promise in treating deep-seated pLGG in children. The treatment has demonstrated a reduction in tumor volume, and the positive results continue over time. LITT can be used as an alternative treatment for tumors located in areas that are difficult to access surgically or in cases where other standard treatment options have failed. [ABSTRACT FROM AUTHOR]

Abstract Objective To investigate the Italian experience on the surgical and radiosurgical treatment of drug‐resistant epilepsy due to hypothalamic hamartoma (HH) in the period 2011–2021 in six Italian epilepsy surgery centers, and to compare safety and efficacy profiles of the different techniques. Methods We collected pseudo‐anonymized patient's data with at least 12 months of follow‐up. Surgical outcome was defined according to Engel classification of seizure outcome. Univariate analysis was performed to assess the risk of post‐operative seizures, categorized in dichotomous variable as favorable and unfavorable; explanatory variables were considered. Mann–Whitney or Chi‐squared test were used to assess the presence of an association between variables (p

New onset refractory status epilepticus (NORSE) is an etiologically heterogeneous condition that is associated with high morbidity and mortality. NORSE is often refractory to medical management prompting a workup for epilepsy surgery. Because NORSE remains etiologically elusive in most cases, surgical evaluations are challenging, especially when the epileptogenic zone (EZ) is not easy to lateralize as can be seen in frontal lobe seizures. Lateralizing a frontal lobe EZ may be challenging due to bilateral synchrony from commissural connections through the corpus callosum and low spatiotemporal resolution of the scalp electroencephalography (EEG). We report a pediatric patient with NORSE presenting with focal impaired awareness seizures clustering into super refractory status epilepticus (SRSE). She required surgical intervention for the treatment of her seizures after failing therapeutic doses of antiseizure medications, anesthetic drips, immunomodulation with methylprednisolone, intravenous immunoglobulin and anakinra, and the ketogenic diet. Despite her semiology being focal, the seizures were not well lateralized on scalp EEG and during phase 2 stereo-EEG (sEEG). Anterior magnetic resonance-guided laser interstitial thermal therapy corpus callosotomy (MRgLITT CC) was performed in a multistage surgical approach to successfully lateralize the EZ with a left-lateralized ictal pattern seen after reimplantation of sEEG electrodes. Our case suggests that minimally invasive MRgLITT CC can be successfully used to lateralize an EZ in frontal lobe epilepsy and that epilepsy surgery should be considered in patients with NORSE with SRSE. We also demonstrate that laser interstitial thermal therapy (LITT), while not always resulting in seizure freedom, can sufficiently disrupt a network to abort status epilepticus and lead to seizure improvements.

Objectives: A surgical "treatment gap" in pediatric epilepsy persists despite the demonstrated safety and effectiveness of surgery. For this reason, the national surgical landscape should be investigated such that an updated assessment may more appropriately guide health care efforts. Methods: In our retrospective cross‐sectional observational study, the National Inpatient Sample (NIS) database was queried for individuals 0 to <18 years of age who had an International Classification of Diseases (ICD) code for drug‐resistant epilepsy (DRE). This cohort was then split into a medical group and a surgical group. The former was defined by ICD codes for ‐DRE without an accompanying surgical code, and the latter was defined by DRE and one of the following epilepsy surgeries: any open surgery; laser interstitial thermal therapy (LITT); vagus nerve stimulation; or responsive neurostimulation (RNS) from 1998 to 2020. Demographic variables of age, gender, race, insurance type, hospital charge, and hospital characteristics were analyzed between surgical options. Continuous variables were analyzed with weight‐adjusted quantile regression analysis, and categorical variables were analyzed by weight‐adjusted counts with percentages and compared with weight‐adjusted chi‐square test results. Results: These data indicate an increase in epilepsy surgeries over a 22‐year period, primarily due to a statistically significant increase in open surgery and a non‐significant increase in minimally invasive techniques, such as LITT and RNS. There are significant differences in age, race, gender, insurance type, median household income, Elixhauser index, hospital setting, and size between the medical and surgical groups, as well as the procedure performed. Significance: An increase in open surgery and minimally invasive surgeries (LITT and RNS) account for the overall rise in pediatric epilepsy surgery over the last 22 years. A positive inflection point in open surgery is seen in 2005. Socioeconomic disparities exist between medical and surgical groups. Patient and hospital sociodemographics show significant differences between the procedure performed. Further efforts are required to close the surgical "treatment gap." [ABSTRACT FROM AUTHOR]

Objective: To investigate the Italian experience on the surgical and radiosurgical treatment of drug‐resistant epilepsy due to hypothalamic hamartoma (HH) in the period 2011–2021 in six Italian epilepsy surgery centers, and to compare safety and efficacy profiles of the different techniques. Methods: We collected pseudo‐anonymized patient's data with at least 12 months of follow‐up. Surgical outcome was defined according to Engel classification of seizure outcome. Univariate analysis was performed to assess the risk of post‐operative seizures, categorized in dichotomous variable as favorable and unfavorable; explanatory variables were considered. Mann–Whitney or Chi‐squared test were used to assess the presence of an association between variables (p < 0.05). Results: Full presurgical and postoperative data about 42 patients from 6 epilepsy surgery centers were gathered. Engel class I was reached in the 65.8% and 66.6% of patients with gelastic and non‐gelastic seizures, respectively. Other than daily non‐gelastic seizures were associated with seizure freedom (p = 0.01), and the radiological type presented a trend toward significance (p = 0.12). Significance: Endoscopic disconnection and laser interstitial thermal therapy are effective in the treatment of HH‐related epilepsy, with a tolerable safety profile. Both gelastic and non‐gelastic seizures can be treated, also in patients with a long history of seizures. Plain Language Summary: This study collected data about 42 patients with HH‐related epilepsies. Endoscopic disconnection and laser therapy are both effective and safe in the treatment of hypothalamic hamartoma‐related epilepsies. [ABSTRACT FROM AUTHOR]

We aimed to compare outcomes including seizure-free status at the last follow-up in adult patients with medically refractory focal epilepsy identified as lesional vs. non-lesional based on their magnetic resonance imaging (MRI) findings who underwent invasive evaluation followed by subsequent resection or thermal ablation (LiTT). We identified 88 adult patients who underwent intracranial monitoring between 2014 and 2021. Of those, 40 received resection or LiTT, and they were dichotomized based on MRI findings, as lesional (N = 28) and non-lesional (N = 12). Patient demographics, seizure characteristics, non-invasive interventions, intracranial monitoring, and surgical variables were compared between the groups. Postsurgical seizure outcome at the last follow-up was rated according to the Engel classification, and postoperative seizure freedom was determined by Kaplan-Meyer survival analysis. Statistical analyses employed Fisher's exact test to compare categorical variables, while a t-test was used for continuous variables. There were no differences in baseline characteristics between groups except for more often noted PET abnormality in the lesional group (p = 0.0003). 64% of the lesional group and 57% of the non-lesional group received surgical resection or LiTT (p = 0.78). At the last follow-up, 78.5% of the patients with lesional MRI findings achieved Engel I outcomes compared to 66.7% of non-lesional patients (p = 0.45). Kaplan-Meier curves did not show a significant difference in seizure-free duration between both groups after surgical intervention (p = 0.49). In our sample, the absence of lesion on brain MRI was not associated with worse seizure outcomes in adult patients who underwent invasive intracranial monitoring followed by resection or thermal ablation. [ABSTRACT FROM AUTHOR]

Background: Essential tremor (ET) affects numerous adults, impacting quality of life (QOL) and often defying pharmacological treatment. Surgical interventions like deep brain stimulation (DBS) and lesional approaches, including radiofrequency, gamma‐knife radiosurgery, and magnetic resonance imaging (MRI)–guided focused ultrasound, offer solutions but are not devoid of limitations. Objectives: This retrospective, single‐center, single‐blinded pilot study aimed to assess the safety and efficacy of unilateral MRI‐guided laser interstitial thermal therapy (MRIg‐LITT) thalamotomy for medically intractable ET. Methods: Nine patients with ET, unresponsive to medications and unsuitable for DBS, underwent unilateral MRIg‐LITT thalamotomy. We assessed tremor severity, QOL, cognitive function, and adverse events (AE) over a 12‐month period. Results: Tremor severity significantly improved, with a reduction of 83.37% at 12 months post‐procedure. QOL scores improved by 74.60% at 12 months. Reported AEs predominantly included transient dysarthria, proprioceptive disturbances, and gait balance issues, which largely resolved within a month. At 3 months, 2 patients (22%) exhibited contralateral hemiparesis requiring physiotherapy, with 1 patient (11%) exhibiting persistent hemiparesis at 12 months. No significant cognitive impairment was detected post‐procedure. Conclusions: Unilateral MRIg‐LITT thalamotomy yielded substantial and enduring tremor alleviation and enhanced QOL in patients with ET that is resistant to medication. The AE profile was acceptable. Our findings support the need for additional research with expanded patient cohorts and extended follow‐up to corroborate these outcomes and to refine the role of MRIg‐LITT as a targeted and minimally invasive approach for ET management. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Laser interstitial thermal therapy (LITT) is a minimally invasive treatment method in managing primary brain neoplasms, brain metastases, radiation necrosis, and epileptogenic lesions, many of which are located in operative corridors that would be difficult to address. Although the use of lasers is not a new concept in neurosurgery, advances in technology have enabled surgeons to perform laser treatment with the aid of real-time MRI thermography as a guide. In this report, we present our institutional series and outcomes of patients treated with LITT. We retrospectively evaluated 19 patients (age range, 28–77 years) who underwent LITT at one or more targets from 2015 to 2019. Primary endpoint observed was mean progression free survival (PFS) and overall survival (OS). Seven patients with glial neoplasms and 12 patients with metastatic disease were reviewed. Average hospitalization was 2.4 days. Median PFS was 7 and 4 months in the metastatic group and primary glial neoplasm group, respectively (p = 0.01). Median OS from time of diagnosis was 41 and 32 months (p = 0.02) and median OS after LITT therapy was 25 and 24 months (p = 0.02) for the metastatic and primary glial neoplasm groups, respectively. One patient experienced immediate post-procedural morbidity secondary to increased intracerebral edema peri-lesionally while one patient experienced post-operative mortality and expired secondary to hemorrhage 1-month post-procedure. Median follow-up was 10 months. Laser interstitial thermal therapy (LITT) is a safe, minimally invasive treatment method that provides surgeons with cytoreductive techniques to treat neurosurgical conditions. Both PFS and OS appear to be more favorable after LITT in patients with metastatic disease. In properly selected patients, this modality offers improved survival outcomes in conjunction with other salvage therapies. [ABSTRACT FROM AUTHOR]

ObjectiveThe authors of this study evaluated the safety and efficacy of stereotactic laser ablation (SLA) for the treatment of drug-resistant epilepsy (DRE) in children.MethodsSeventeen North American centers were enrolled in the study. Data for pediatric patients with DRE who had been treated with SLA between 2008 and 2018 were retrospectively reviewed.ResultsA total of 225 patients, mean age 12.8 ± 5.8 years, were identified. Target-of-interest (TOI) locations included extratemporal (44.4%), temporal neocortical (8.4%), mesiotemporal (23.1%), hypothalamic (14.2%), and callosal (9.8%). Visualase and NeuroBlate SLA systems were used in 199 and 26 cases, respectively. Procedure goals included ablation (149 cases), disconnection (63), or both (13). The mean follow-up was 27 ± 20.4 months. Improvement in targeted seizure type (TST) was seen in 179 (84.0%) patients. Engel classification was reported for 167 (74.2%) patients; excluding the palliative cases, 74 (49.7%), 35 (23.5%), 10 (6.7%), and 30 (20.1%) patients had Engel class I, II, III, and IV outcomes, respectively. For patients with a follow-up ≥ 12 months, 25 (51.0%), 18 (36.7%), 3 (6.1%), and 3 (6.1%) had Engel class I, II, III, and IV outcomes, respectively. Patients with a history of pre-SLA surgery related to the TOI, a pathology of malformation of cortical development, and 2+ trajectories per TOI were more likely to experience no improvement in seizure frequency and/or to have an unfavorable outcome. A greater number of smaller thermal lesions was associated with greater improvement in TST. Thirty (13.3%) patients experienced 51 short-term complications including malpositioned catheter (3 cases), intracranial hemorrhage (2), transient neurological deficit (19), permanent neurological deficit (3), symptomatic perilesional edema (6), hydrocephalus (1), CSF leakage (1), wound infection (2), unplanned ICU stay (5), and unplanned 30-day readmission (9). The relative incidence of complications was higher in the hypothalamic target location. Target volume, number of laser trajectories, number or size of thermal lesions, or use of perioperative steroids did not have a significant effect on short-term complications.ConclusionsSLA appears to be an effective and well-tolerated treatment option for children with DRE. Large-volume prospective studies are needed to better understand the indications for treatment and demonstrate the long-term efficacy of SLA in this population.

BackgroundLaser interstitial thermal therapy (LITT) in the setting of post-SRS radiation necrosis (RN) for patients with brain metastases has growing evidence for efficacy. However, questions remain regarding hospitalization, local control, symptom control, and concurrent use of therapies.MethodsDemographics, intraprocedural data, safety, Karnofsky performance status (KPS), and survival data were prospectively collected and then analyzed on patients who consented between 2016-2020 and who were undergoing LITT for biopsy-proven RN at one of 14 US centers. Data were monitored for accuracy. Statistical analysis included individual variable summaries, multivariable Fine and Gray analysis, and Kaplan-Meier estimated survival.ResultsNinety patients met the inclusion criteria. Four patients underwent 2 ablations on the same day. Median hospitalization time was 32.5 hours. The median time to corticosteroid cessation after LITT was 13.0 days (0.0, 1229.0) and cumulative incidence of lesional progression was 19% at 1 year. Median post-procedure overall survival was 2.55 years [1.66, infinity] and 77.1% at one year as estimated by KaplanMeier. Median KPS remained at 80 through 2-year follow-up. Seizure prevalence was 12% within 1-month post-LITT and 7.9% at 3 months; down from 34.4% within 60-day prior to procedure.ConclusionsLITT for RN was not only again found to be safe with low patient morbidity but was also a highly effective treatment for RN for both local control and symptom management (including seizures). In addition to averting expected neurological death, LITT facilitates ongoing systemic therapy (in particular immunotherapy) by enabling the rapid cessation of steroids, thereby facilitating maximal possible survival for these patients.

Purpose: Radiation necrosis (RN) is a local inflammatory reaction that arises in response to radiation injury and may cause significant morbidity. This study aims to evaluate and compare the efficacy of bevacizumab and laser interstitial thermal therapy (LITT) in treating RN in patients with previously radiated central nervous system (CNS) neoplasms. Methods: PubMed, Cochrane, Scopus, and EMBASE databases were screened. Studies of patients with radiation necrosis from primary or secondary brain tumors were included. Indirect meta-analysis with random-effect modeling was performed to compare clinical and radiological outcomes. Results: Twenty-four studies were included with 210 patients in the bevacizumab group and 337 patients in the LITT group. Bevacizumab demonstrated symptomatic improvement/stability in 87.7% of cases, radiological improvement/stability in 86.2%, and steroid wean-off in 45%. LITT exhibited symptomatic improvement/stability in 71.2%, radiological improvement/stability in 64.7%, and steroid wean-off in 62.4%. Comparative analysis revealed statistically significant differences favoring bevacizumab in symptomatic improvement/stability (p = 0.02), while no significant differences were observed in radiological improvement/stability (p = 0.27) or steroid wean-off (p = 0.90). The rates of adverse reactions were 11.2% for bevacizumab and 14.9% for LITT (p = 0.66), with the majority being grade 2 or lower (72.2% for bevacizumab and 62.5% for LITT). Conclusion: Both bevacizumab and LITT exhibited favorable clinical and radiological outcomes in managing RN. Bevacizumab was found to be associated with better symptomatic control compared to LITT. Patient-, diagnosis- and lesion-related factors should be considered when choosing the ideal treatment modality for RN to enhance overall patient outcomes. [ABSTRACT FROM AUTHOR]

Laser interstitial thermal therapy (LITT), which ablates diseased brain tissues via hyperthermia, has offered novel treatment approach for epilepsy; however, the current LITT protocols still lack ablation selectivity and disease‐modifying efficacy. A second near‐infrared (NIR‐II) activatable nitric oxide (NO) releasing nanoactuator is reported here for photothermal combinational modulation of epileptogenic focus. The nanoactuator is prepared by conjugating NO donor S‐nitrosoglutathione (GSNO) onto polydopamine‐coated gold (Au) nanoparticles (NPs), which shows excellent photothermal conversion capability and controlled NO‐releasing property upon illumination in the NIR‐II window. Both in vitro and in vivo study demonstrate that the nanoactuator could exert stronger cell killing effects as compared to its counterpart. Furthermore, the NIR‐II‐activated NO release could inhibit P‐gp expression by regulating NF‐κb pathway, resulting in reprogramming of epileptogenic microenvironment. This study thus offers a novel regulating strategy for the treatment of drug‐resistant epilepsy. [ABSTRACT FROM AUTHOR]

We aim to investigate the efficacy and safety of laser interstitial thermal therapy (LITT) in treating recurrent glioblastomas (rGBMs). A comprehensive search was conducted in four databases to identify studies published between January 2001 and June 2022 that reported prognosis information of rGBM patients treated with LITT as the primary therapy. The primary outcomes of interest were progression-free survival (PFS) and overall survival (OS) at 6 and 12 months after LITT intervention. Adverse events and complications were also evaluated. Eight eligible non-comparative studies comprising 128 patients were included in the analysis. Seven studies involving 120 patients provided data for the analysis of PFS. The pooled PFS rate at 6 months after LITT was 25% (95% CI 15–37%, I2 = 53%), and at 12 months, it was 9% (95% CI 4–15%, I2 = 24%). OS analysis was performed on 54 patients from six studies, with an OS rate of 92% (95% CI 84–100%, I2 = 0%) at 6 months and 42% (95% CI 13–73%, I2 = 67%) at 12 months after LITT. LITT demonstrates a favorable safety profile with low complication rates and promising tumor control and overall survival rates in patients with rGBMs. Tumor volume and performance status are important factors that may influence the effectiveness of LITT in selected patients. Additionally, the combination of LITT with immune-based therapy holds promise. Further well-designed clinical trials are needed to expand the application of LITT in glioma treatment. [ABSTRACT FROM AUTHOR]

Background. Laser interstitial thermal therapy (LITT) is one of the most effective and economically justified methods, which is recommended as the first-line treatment for patients with compression syndrome, a significant cosmetic defect, and those who categorically refuse surgery or have contraindications to it. The purpose of the study was to analyze the short-term outcomes of LITT in patients with euthyroid nodular goiter. Materials and methods. The results of LITT were analyzed in 20 patients with euthyroid nodular goiter, Bethesda category II, and solid echostructure for 2021–2023. The average volume of nodules was 0.67 (0.16; 1.39) cm3. Medical GaAlAs diode laser VELAS II-30F was used. The response of the nodules was classified as positive effect if volume reduction rate (VRR) was above 70 %, absent with VRR 69–0 %, negative effect with VRR < 0 %. The total follow-up ranged from 1 to 24 months. Results. A linear regression analysis revealed that shrinkage of the final nodule volume after the first session (0.37 (0.06; 0.9) cm3) statistically significantly depended on the initial volume (0.67 (0.16; 1.39) cm3), R2 = 0.955, p < 0.001. A positive effect was observed only in nodules up to 1.0 cm3 (average of 0.16 (0.085; 0.31) cm3). Statistically significant correlation was not found after the first session between the effect and the initial nodule volume (r = –0.163, p = 0.49). A linear regression analysis showed the absence of statistically significant correlation between the final nodule volume, final VRR, and laser characteristics (p > 0.05). The final nodule volume after the second session decreased statistically significantly vs. initial one (p = 0.007) and vs. the final volume after the first session (p = 0.028). There was no statistically significant difference between the frequency of effect in patients after single LITT and in those with two sessions (χ2 = 2.14, p = 0.34). A linear regression analysis did not show statistically significant causal relationship between these indicators (R2 = 0.27, p = 0.12). Conclusions. Laser interstitial thermal therapy is a safe method of organ-preserving treatment in patients with the euthyroid nodular goiter, which can be performed on an outpatient basis and does not lead to thyroid dysfunction. LITT is the most effective with a volume nodule of up to 1.0 cm3. The use of LITT in nodules larger than 1.0 cm3 does not meet the criteria of technical “success” but this does not necessarily indicate the overall ineffectiveness since the sample volume was insufficient. For greater validity, a study should be conducted on a larger sample of patients, which will allow reliably assessing the effectiveness of the method and determining clear criteria of selecting patients for this intervention. The study is still in progress.

Purpose: Laser interstitial thermal therapy (LITT) is a minimally invasive cytoreductive treatment option for brain tumors with a risk of vascular injury from catheter placement or thermal energy. This may be of concern with deep-seated tumors that have surrounding end-artery perforators and critical microvasculature. The purpose of this study was to assess the risk of distal ischemia following LITT for deep-seated perivascular brain tumors. Methods: A retrospective review of a multi-institution database was used to identify patients who underwent LITT between 2013 and 2022 for tumors located within the insula, thalamus, basal ganglia, and anterior perforated substance. Demographic, clinical and volumetric tumor characteristics were collected. The primary outcome was radiographic evidence of distal ischemia on post-ablation magnetic resonance imaging (MRI). Results: 61 LITT ablations for deep-seated perivascular brain tumors were performed. Of the tumors treated, 24 (39%) were low-grade gliomas, 32 (52%) were high-grade gliomas, and 5 (8%) were metastatic. The principal location included 31 (51%) insular, 14 (23%) thalamic, 13 (21%) basal ganglia, and 3 (5%) anterior perforated substance tumors. The average tumor size was 19.6 cm3 with a mean ablation volume of 11.1 cm3. The median extent of ablation was 92% (IQR 30%, 100%). Two patients developed symptomatic intracerebral hemorrhage after LITT. No patient had radiographic evidence of distal ischemia on post-operative diffusion weighted imaging. Conclusion: We demonstrate that LITT for deep-seated perivascular brain tumors has minimal ischemic risks and is a feasible cytoreductive treatment option for otherwise difficult to access intracranial tumors. [ABSTRACT FROM AUTHOR]

Introduction: Thalamic gliomas pose a particular therapeutic challenge as complete resection is rarely achieved due to the deep and eloquent location. Laser interstitial thermal therapy (LITT) may provide a valuable management option for deep-seated gliomas that are not accessible with open surgery. Case Presentation: A 57-year-old woman presented with a rapidly progressive large thalamic glioblastoma. Opting for full ablation, we selected a challenging trajectory to maximize the possibility of full ablation. At 2.4 cm in diameter, the tumour was larger than recommended for LITT; nevertheless, three laser ablations along a single trajectory resulted in macroscopic ablation without complications. Adjuvant radio-chemotherapy was started soon after surgery without radiological recurrence 1.5 years after the initial surgery. Conclusion: This case demonstrates the potential when thalamic tumours are managed with timely LITT treatment and meticulous trajectory planning. Moreover, it highlights the need for close interdisciplinary management with neurosurgeons, neuropathologists, neuroradiologists, and neurooncologists. [ABSTRACT FROM AUTHOR]

Simple Summary: Advancements in understanding the blood–brain barrier (BBB) and blood–tumor barrier (BTB) structures emphasize the need to explore functional differences influencing drug distribution to the central nervous system (CNS). Various methods for overcoming the BBB/BTB have been proposed. Osmotic BBB disruption with intra-arterial administration effectively obtains local, clinically relevant concentrations in large brain areas, with an acceptable safety profile in experienced hands. Convection-enhanced delivery allows for homogenous and safe drug delivery to the tumor but demands further technical refinement and clinical evaluation. Emerging therapies like high-intensity focused and low-intensity pulsed ultrasound show great promise in delivering large therapeutic agents to small brain areas. While laser interstitial thermal therapy is effective in ablating local brain tumors, its impact on disrupting the BBB remains inadequately understood. Similarly, tumor-treating fields aid chemotherapy in inducing cycle arrest, but the proof of their ability to disrupt the BBB/BTB has been so far limited to preclinical studies. The blood–brain barrier (BBB) poses a significant challenge to drug delivery for brain tumors, with most chemotherapeutics having limited permeability into non-malignant brain tissue and only restricted access to primary and metastatic brain cancers. Consequently, due to the drug's inability to effectively penetrate the BBB, outcomes following brain chemotherapy continue to be suboptimal. Several methods to open the BBB and obtain higher drug concentrations in tumors have been proposed, with the selection of the optimal method depending on the size of the targeted tumor volume, the chosen therapeutic agent, and individual patient characteristics. Herein, we aim to comprehensively describe osmotic disruption with intra-arterial drug administration, intrathecal/intraventricular administration, laser interstitial thermal therapy, convection-enhanced delivery, and ultrasound methods, including high-intensity focused and low-intensity ultrasound as well as tumor-treating fields. We explain the scientific concept behind each method, preclinical/clinical research, advantages and disadvantages, indications, and potential avenues for improvement. Given that each method has its limitations, it is unlikely that the future of BBB disruption will rely on a single method but rather on a synergistic effect of a combined approach. Disruption of the BBB with osmotic infusion or high-intensity focused ultrasound, followed by the intra-arterial delivery of drugs, is a promising approach. Real-time monitoring of drug delivery will be necessary for optimal results. [ABSTRACT FROM AUTHOR]

Background. Laser interstitial thermal therapy (LITT) is one of the most effective and economically justified methods, which is recommended as the first-line treatment for patients with compression syndrome, a significant cosmetic defect, and those who categorically refuse surgery or have contraindications to it. The purpose of the study was to analyze the short-term outcomes of LITT in patients with euthyroid nodular goiter. Materials and methods. The results of LITT were analyzed in 20 patients with euthyroid nodular goiter, Bethesda category II, and solid echostructure for 2021–2023. The average volume of nodules was 0.67 (0.16; 1.39) cm³ . Medical GaAlAs diode laser VELAS II-30F was used. The response of the nodules was classified as positive effect if volume reduction rate (VRR) was above 70 %, absent with VRR 69–0 %, negative effect with VRR < 0 %. The total follow-up ranged from 1 to 24 months. Results. A linear regression analysis revealed that shrinkage of the final nodule volume after the first session (0.37 (0.06; 0.9) cm³ ) statistically significantly depended on the initial volume (0.67 (0.16; 1.39) cm³ ), R² = 0.955, p < 0.001. A positive effect was observed only in nodules up to 1.0 cm³ (average of 0.16 (0.085; 0.31) cm³ ). Statistically significant correlation was not found after the first session between the effect and the initial nodule volume (r = –0.163, p = 0.49). A linear regression analysis showed the absence of statistically significant correlation between the final nodule volume, final VRR, and laser characteristics (p > 0.05). The final nodule volume after the second session decreased statistically significantly vs. initial one (p = 0.007) and vs. the final volume after the first session (p = 0.028). There was no statistically significant difference between the frequency of effect in patients after single LITT and in those with two sessions (χ² = 2.14, p = 0.34). A linear regression analysis did not show statistically significant causal relationship between these indicators (R² = 0.27, p = 0.12). Conclusions. Laser interstitial thermal therapy is a safe method of organ-preserving treatment in patients with the euthyroid nodular goiter, which can be performed on an outpatient basis and does not lead to thyroid dysfunction. LITT is the most effective with a volume nodule of up to 1.0 cm³ . The use of LITT in nodules larger than 1.0 cm³ does not meet the criteria of technical “success” but this does not necessarily indicate the overall ineffectiveness since the sample volume was insufficient. For greater validity, a study should be conducted on a larger sample of patients, which will allow reliably assessing the effectiveness of the method and determining clear criteria of selecting patients for this intervention. The study is still in progress. [ABSTRACT FROM AUTHOR]

Laser interstitial thermal therapy (LITT), which ablates diseased brain tissues via hyperthermia, has offered novel treatment approach for epilepsy; however, the current LITT protocols still lack ablation selectivity and disease‐modifying efficacy. A second near‐infrared (NIR‐II) activatable nitric oxide (NO) releasing nanoactuator is reported here for photothermal combinational modulation of epileptogenic focus. The nanoactuator is prepared by conjugating NO donor S‐nitrosoglutathione (GSNO) onto polydopamine‐coated gold (Au) nanoparticles (NPs), which shows excellent photothermal conversion capability and controlled NO‐releasing property upon illumination in the NIR‐II window. Both in vitro and in vivo study demonstrate that the nanoactuator could exert stronger cell killing effects as compared to its counterpart. Furthermore, the NIR‐II‐activated NO release could inhibit P‐gp expression by regulating NF‐κb pathway, resulting in reprogramming of epileptogenic microenvironment. This study thus offers a novel regulating strategy for the treatment of drug‐resistant epilepsy.

Central nervous system (CNS) tumors pose a substantial risk to human health. Conventional therapeutic modalities, including surgical excision, radiotherapy, and chemotherapy, exhibit inherent limitations and adverse effects. Nonetheless, the emergence of minimally invasive surgical techniques and advanced imaging technology have spurred research interest in the realm of neurology toward developing minimally invasive treatments for neurosurgical tumors. These approaches encompass tumor laser interstitial thermal therapy, tumor treating fields, photodynamic therapy, and other related interventions. Minimally invasive treatments offer notable advantages, such as reduced tissue trauma, expedited recovery, and pronounced therapeutic efficacy, rendering them extensively employed in clinical settings. This comprehensive review aims to elucidate accomplishments in the field of minimally invasive CNS tumor treatments while delineating prospective avenues for future development.

BackgroundTreatment options for unresectable new and recurrent glioblastoma remain limited. Laser ablation has demonstrated safety as a surgical approach to treating primary brain tumors. The LAANTERN prospective multicenter registry (NCT02392078) data were analyzed to determine clinical outcomes for patients with new and recurrent IDH wild-type glioblastoma.MethodsDemographics, intraprocedural data, adverse events, KPS, health economics, and survival data were prospectively collected and then analyzed on IDH wild-type newly diagnosed and recurrent glioblastoma patients who were treated with laser ablation at 14 US centers between January 2016 and May 2019. Data were monitored for accuracy. Statistical analysis included individual variable summaries, multivariable differences in survival, and median survival numbers.ResultsA total of 29 new and 60 recurrent IDH wild-type WHO grade 4 glioblastoma patients were treated. Positive MGMT promoter methylation status was present in 5/29 of new and 23/60 of recurrent patients. Median physician-estimated extent of ablation was 91%-99%. Median overall survival (OS) was 9.73 months (95% confidence interval: 5.16, 15.91) for newly diagnosed patients and median post-procedure survival was 8.97 months (6.94, 12.36) for recurrent patients. Median OS for newly diagnosed patients receiving post-LITT chemo/radiation was 16.14 months (6.11, not reached). Factors associated with improved survival were MGMT promoter methylation, adjuvant chemotherapy within 12 weeks, and tumor volume

Background and objectives: Gelastic seizures due to hypothalamic hamartomas (HH) are challenging to treat, in part due to an incomplete understanding of seizure propagation pathways. Although magnetic resonance imaging-guided laser interstitial thermal therapy (MRgLITT) is a promising intervention to disconnect HH from ictal propagation networks, the optimal site of ablation to achieve seizure freedom is not known. In this study, we investigated intraoperative post-ablation changes in resting-state functional connectivity to identify large-scale networks associated with successful disconnection of HH. Methods: Children who underwent MRgLITT for HH at two institutions were consecutively recruited and followed for a minimum of one year. Seizure freedom was defined as Engel score of 1A at the last available follow-up. Immediate pre- and post- ablation resting-state functional MRI scans were acquired while maintaining a constant depth of general anesthetic. Multivariable generalized linear models were used to identify intraoperative changes in large-scale connectivity associated with seizure outcomes. Results: Twelve patients underwent MRgLITT for HH, five of whom were seizure-free at their last follow-up. Intraprocedural changes in thalamocortical circuitry involving the anterior cingulate cortex were associated with seizure-freedom. Children who were seizure-free demonstrated an increase and decrease in connectivity to the pregenual and dorsal anterior cingulate cortices, respectively. In addition, children who became seizure-free demonstrated increased thalamic connectivity to the periaqueductal gray immediately following MRgLITT. Discussion: Successful disconnection of HH is associated with intraoperative, large-scale changes in thalamocortical connectivity. These changes provide novel insights into the large-scale basis of gelastic seizures and may represent intraoperative biomarkers of treatment success.

Responsive neurostimulation (RNS) is a valuable tool in the diagnosis and treatment of medication refractory epilepsy (MRE) and provides clinicians with better insights into patients’ seizure patterns. In this case illustration, we present a patient with bilateral hippocampal RNS for presumed bilateral mesial temporal lobe epilepsy. The patient subsequently underwent a right sided LITT amygdalohippocampotomy based upon chronic RNS data revealing predominance of seizures from that side. Analyzing electrocorticography (ECOG) from the RNS system, we identified the frequency of high amplitude discharges recorded from the left hippocampal lead pre- and post- right LITT amygdalohippocampotomy. A reduction in contralateral interictal epileptiform activity was observed through RNS recordings over a two-year period, suggesting the potential dependency of the contralateral activity on the primary epileptogenic zone. These findings suggest that early targeted surgical resection or laser ablation by leveraging RNS data can potentially impede the progression of dependent epileptiform activity and may aid in preserving neurocognitive networks. RNS recordings are essential in shaping further management decisions for our patient with a presumed bitemporal epilepsy.

AbstractThe purpose of the study is to retrospectively evaluate the development and technological progress in local oncological treatments of patients with breast cancer liver metastasis (BCLM) using LITT (laser interstitial thermotherapy), MWA (microwave ablation) and TACE (transarterial chemoembolization) ablation techniques in a multimodal application. The study uses data generated between 1993 and 2020. Therapy results were evaluated using the Kaplan–Meier survival estimate, Cox proportional hazard regression and log-rank test. Cox regression analysis showed that the different treatment methods are statistically significant predictors of survival of patients. Median survival times for groups treated with LITT (212 patients) and LITT + TACE (215 patients) were 2.2 years and 2.1 years respectively; median survival times for groups treated with MWA (17 patients) and MWA + TACE (143 patients) were 5.6 and 2.4 years respectively. For LITT only treatments, the 1-, 3- and 5-year survival probability scored 80%, 37%, 22%. Results for combined LITT + TACE treatments were 76%, 34% and 15%. In group MWA, the 1-/3-/5-year survival probability rates were calculated as 89%, 89%, 89% (however, they should be interpreted carefully due to a relatively small sample size of n = 17 patients). Group MWA + TACE offered values of 77%, 38% and 22%. A separate group of 549 patients was analyzed with TACE monotherapy treatment. The estimated median survival time in this group was 0.8 years. The 1-/3-/5-year survival probability rates were 37%, 8% and 4%. Treatments with combined MWA and MWA + TACE resulted in the best median survival time estimations in this study.

Primitive neuroectodermal tumors of the central nervous system, or CNS neuroblastoma, are rare neoplasms in children. Recently, methylation profiling enabled the discovery of four distinct entities of these tumors. The current treatment paradigm involves surgical resection followed by chemotherapy and radiation. However, upfront surgical resection carries high surgical morbidity in this patient population due to their young age, tumor vascularity, and often deep location in the brain. We report a case of CNS neuroblastoma that can be successfully treated with neoadjuvant chemotherapy followed by minimally invasive laser interstitial thermal therapy and radiation. The patient has complete treatment with no evidence of recurrence at one year follow-up. This case illustrates a potential paradigm shift in the treatment of these rare tumors can be treated using minimally invasive surgical approach to achieve a favorable outcome. [ABSTRACT FROM AUTHOR]

Magnetic resonance thermography−guided laser interstitial thermal therapy (LITT) provides a minimally invasive treatment option in children with central nervous system tumors or medically intractable epilepsy. However, transporting anesthetized children between an operating room (OR) and a radiologic suite creates logistical challenges. Thus we describe advantages of using a 2-room intraoperative magnetic resonance imaging (MRI) concept for LITT. Patients were pinned in a head frame that doubles as the lower part of the MRI head coil. Preoperative MRI was performed for accurate neuronavigation, after which laser fibers were stereotactically implanted. Transport between OR and MRI was achieved by sliding the top of the OR table onto a trolly. We performed 12 procedures in 11 children, mean age 7.1 years (range: 2 to 14 years). Ten children suffered from medically intractable epilepsy, and 1 child had a pilocytic midbrain astrocytoma. Two fibers were placed in 8 and 1 fiber in 4 procedures. Mean entry point and target errors were 2.8 mm and 3.4 mm, respectively. Average transfer time from OR to MRI and vice versa was 9 minutes (±1 minute, 40 seconds). Altogether, 50% of the seizure patients were seizure free (Engel grade I) at 22 months' follow-up time. One hemorrhagic event, which could be managed nonoperatively, occurred. We recorded no surgical site or intracranial infections. All LITT procedures were successfully carried out with head frame in the sterile environment. The intraoperative MRI suite proved to be advantageous for minimally invasive procedures, especially in young children resulting in short transports while maintaining high accuracy and safety. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) tumors pose a substantial risk to human health. Conventional therapeutic modalities, including surgical excision, radiotherapy, and chemotherapy, exhibit inherent limitations and adverse effects. Nonetheless, the emergence of minimally invasive surgical techniques and advanced imaging technology have spurred research interest in the realm of neurology toward developing minimally invasive treatments for neurosurgical tumors. These approaches encompass tumor laser interstitial thermal therapy, tumor treating fields, photodynamic therapy, and other related interventions. Minimally invasive treatments offer notable advantages, such as reduced tissue trauma, expedited recovery, and pronounced therapeutic efficacy, rendering them extensively employed in clinical settings. This comprehensive review aims to elucidate accomplishments in the field of minimally invasive CNS tumor treatments while delineating prospective avenues for future development. [ABSTRACT FROM AUTHOR]

Introduction: Laser interstitial thermal therapy (LITT) at 1064 nm is widely used to treat epilepsy and brain tumors; however, no numerical model exists that can predict the ablation region with careful in vivo validation. Methods: In this study, we proposed a model with a system of finite element methods simulating heat transfer inside the brain tissue, radiative transfer from the applicator into the brain tissue, and a model for tissue damage. Results: To speed up the computation for practical applications, we also validated P1-approximation as an efficient and fast method for calculating radiative transfer by comparing it with Monte Carlo simulation. Finally, we validated the proposed numerical model in vivo on six healthy canines and eight human patients with epilepsy and found strong agreement between the predicted temperature profile and ablation area and the magnetic resonance imaging-measured results. Discussion: Our results demonstrate the feasibility and reliability of the model in predicting the ablation area of 1,064 nm LITT, which is important for presurgical planning when using LITT. [ABSTRACT FROM AUTHOR]

Epilepsy is a common condition that affects approximately 1% of the world's population, with about one-third being refractory epilepsy. Temporal lobe epilepsy is the most common type of drug-resistant epilepsy, and laser interstitial thermal therapy (LITT) is an innovative treatment. In this systematic review and meta-analysis, we aimed to summarize the current evidence on outcomes after LITT, including seizure freedom rate, complication rate, and neurocognitive outcome. PubMed and OVID Medline search engines were systematically searched for all indexed publications in the English language up to July15, 2023. The search was limited to human studies. Proportions and 95% confidence interval (CI) values were calculated for seizure, neurocognitive outcome, and complication rate. A total of 836 patients were included. Overall seizure outcomes, regardless of the pathology, included Engel I outcome in 56% (95% CI, 52.4–59.5%), Engel II outcome in 19.2% (95% CI, 15.4–23.6%), Engel III outcome in 17.3% (95% CI, 13.5–21.8%), and Engel IV outcome in 10.5% (95% CI 6.3–17%) of the patients. The overall decline in verbal and visual memory regardless of laterality was 24.2 (95% CI 8.6–52%) and 25.2% (8.3–55.8%). For naming, the decline was 13.4% (6.6–25.4%). The results of the pooled analysis in comparison with available data in the literature showed that seizure outcomes after LITT were slightly inferior to published data after temporal lobectomy. Data on cognitive outcomes after LITT are scarce and heterogeneous. [ABSTRACT FROM AUTHOR]

Three studies have reported trigeminal hypesthesia following temporal lobe resection. However, no cases of hypesthesia have been reported following laser interstitial thermal therapy (LITT). We report the first case of trigeminal hypesthesia as a complication of otherwise successful LITT in a patient with drug-resistant epilepsy. A 58-year-old male with drug-resistant epilepsy secondary to a left parahippocampal gyrus multinodular and vacuolating neuronal tumor underwent biopsy and MRI-guided LITT. Immediately postoperatively, the patient reported hypesthesia in the left V3 distribution, including inside the mouth and ear. At 6-month follow-up, hypesthesia was present but improving, and the patient was seizure-free. While the cerebellopontine angle and prepontine cisterns are considered thermal insulators, we hypothesize that thermal injury was conducted through these spaces to the cisternal segment of the trigeminal nerve or to the inferior V3 branch in Meckel's cave. Moreover, real-time visualization of the ablation is impacted by a blind spot at the skull base, created from bone disruption of MRI thermography. [ABSTRACT FROM AUTHOR]

Objective: To evaluate declarative memory outcomes in medically refractory epilepsy patients who underwent either a highly selective laser ablation of the amygdalohippocampal complex or a conventional open temporal lobe resection. Methods: Post-operative change scores were examined for verbal memory outcome in epilepsy patients who underwent stereotactic laser amygdalohippocampotomy (SLAH: n = 40) or open resection procedures (n = 40) using both reliable change index (RCI) scores and a 1-SD change metric. Results: Using RCI scores, patients undergoing open resection (12/40, 30.0%) were more likely to decline on verbal memory than those undergoing SLAH (2/40 [5.0%], p = 0.0064, Fisher's exact test). Patients with language dominant procedures were much more likely to experience a significant verbal memory decline following open resection (9/19 [47.4%]) compared to laser ablation (2/19 [10.5%], p = 0.0293, Fisher's exact test). 1 SD verbal memory decline frequently occurred in the open resection sample of language dominant temporal lobe patients with mesial temporal sclerosis (8/10 [80.0%]), although it rarely occurred in such patients after SLAH (2/14, 14.3%) (p = 0.0027, Fisher's exact test). Memory improvement occurred significantly more frequently following SLAH than after open resection. Interpretation: These findings suggest that while verbal memory function can decline after laser ablation of the amygdalohippocampal complex, it is better preserved when compared to open temporal lobe resection. Our findings also highlight that the dominant hippocampus is not uniquely responsible for verbal memory. While this is at odds with our simple and common heuristic of the hippocampus in memory, it supports the findings of non-human primate studies showing that memory depends on broader medial and lateral TL regions.

IntroductionIt is now understood that in focal epilepsy, impacted neural regions are not limited to the epileptogenic zone. As such, further investigation into the underlying functional connectivity (FC) patterns in those enduring Temporal Lobe Epilepsy (TLE) with Mesial Temporal Sclerosis (MTS) is imperative to understanding the intricacies of the disease.MethodsThe rsfMRIs of 17 healthy participants, 10 left-sided TLE-MTS patients with a pre-operative history of focal impaired awareness seizures (FIA), and 13 left-sided TLE-MTS patients with a pre-operative history of focal aware seizures (FA) were compared to determine the existence of distinct FC patterns with respect to seizure types. Similarly, the rsfMRIs of the above-mentioned healthy participants, 16 left-sided TLE-MTS individuals who were seizure-free (SF) 12 months postoperatively, and 16 left-sided TLE-MTS persons without seizure freedom (nSF) were interrogated. The ROI-to-ROI connectivity analysis included a total of 175 regions of interest (ROIs) and accounted for both age and duration of epileptic activity. Significant correlations were determined via two-sample t-tests and Bonferroni correction (α = 0.05).ResultsComparisons of FA and FIA groups depicted significant correlations between the contralateral anterior cingulate gyrus, subgenual region, and the contralateral cerebellum, lobule III (p-value = 2.26e-4, mean z-score = −0.05 ± 0.28, T = −4.23). Comparisons of SF with nSF depicted two significantly paired-ROIs; the contralateral amygdala and the contralateral precuneus (p-value = 2.9e-5, mean z-score = −0.12 ± 0.19, T = 4.98), as well as the contralateral locus coeruleus and the ipsilateral intralaminar nucleus (p-value= 1.37e-4, mean z-score = 0.06 ± 0.17, T = −4.41).SignificanceFC analysis proves to be a lucrative modality for exploring unique signatures with respect to seizure types and postoperative outcomes. By furthering our understanding of the differences between epileptic phenotypes, we can achieve improvement in future treatment modalities not limited to targeting advancements.

Objective: Stereoelectroencephalography (SEEG)‐guided radiofrequency ablation (RFA) is increasingly being used as a treatment for drug‐resistant localization‐related epilepsy. The aim of this study is to analyze the successes and failures using RFA and how response correlates with surgical epilepsy treatment outcomes. Methods: We retrospectively reviewed 62 patients who underwent RFA via SEEG electrodes. After excluding five, the remaining 57 were classified into subgroups based on procedures and outcomes. Forty patients (70%) underwent a secondary surgical procedure, of whom 32 were delayed: 26 laser interstitial thermal therapy (LITT), five resection, one neuromodulation. We determined the predictive value of RFA outcome upon subsequent surgical outcome by categorizing the delayed secondary surgery outcome as success (Engel I/II) versus failure (Engel III/IV). Demographic information, epilepsy characteristics, and the transient time of seizure freedom after RFA were calculated for each patient. Results: Twelve of 49 patients (24.5%) who had RFA alone and delayed follow‐up achieved Engel class I. Of the 32 patients who underwent a delayed secondary surgical procedure, 15 achieved Engel class I and nine Engel class II (24 successes), and eight were considered failures (Engel class III/IV). The transient time of seizure freedom after RFA was significantly longer in the success group (4 months, SD = 2.6) as compared to the failure group (.75 months, SD = 1.16; p <.001). Additionally, there was a higher portion of preoperative lesional findings in patients in the RFA alone and delayed surgical success group (p =.03) and a longer time to seizure recurrence in the presence of lesions (p <.05). Side effects occurred in 1% of patients. Significance: In this series, RFA provided a treatment during SEEG‐guided intracranial monitoring that led to seizure freedom in ~25% of patients. Of the 70% who underwent delayed surgery, longer transient time of seizure freedom after RFA was predictive of the results of the secondary surgeries, 74% of which were LITT. [ABSTRACT FROM AUTHOR]

Background: Medically intractable Parkinson's disease (PD) tremor is a common difficult clinical situation with major impact on patient's quality of life (QOL). Deep brain stimulation (DBS) is an effective therapy but is not an option for many patients. Less invasive lesional brain surgery procedures, such as thalamotomy, have proven to be effective in these indications. Here, we describe the technical nuances and advantages of stereotactic robot-assisted MRI-guided laser interstitial thermal therapy (MRIg-LITT) thalamotomy for medically intractable PD tremor. Method: We describe 2 patients with medically intractable PD tremor treated with stereotactic robot-assisted MRIg-LITT thalamotomy performed under general anesthesia with intraoperative electrophysiological testing. Pre and postoperative tremor scores were assessed using the Fahn-Tolosa-Marin tremor rating scale (TRS). Results: At 3-month follow-up, both patients demonstrated significant improvement in tremor symptoms subjectively and according to the TRS (75% for both). Patients also had substantial improvements in their QOL (32.54% and 38%) according to the 39-item PD questionnaire. Both patients underwent uncomplicated MRIg-LITT thalamotomy. Conclusions: In patients with medically intractable PD tremor who are unsuitable candidates for DBS, thalamotomy utilizing a stereotactic robot, intraoperative electrophysiological testing, and laser ablation with real-time MRI guidance may be a viable treatment option. However, further studies with larger sample sizes and longer follow-up periods are necessary to confirm these preliminary results. [ABSTRACT FROM AUTHOR]

Objective: Stereotactic laser amygdalohippocampotomy (SLAH) is an appealing option for patients with temporal lobe epilepsy, who often require intracranial monitoring to confirm mesial temporal seizure onset. However, given limited spatial sampling, it is possible that stereotactic electroencephalography (stereo‐EEG) may miss seizure onset elsewhere. We hypothesized that stereo‐EEG seizure onset patterns (SOPs) may differentiate between primary onset and secondary spread and predict postoperative seizure control. In this study, we characterized the 2‐year outcomes of patients who underwent single‐fiber SLAH after stereo‐EEG and evaluated whether stereo‐EEG SOPs predict postoperative seizure freedom. Methods: This retrospective five‐center study included patients with or without mesial temporal sclerosis (MTS) who underwent stereo‐EEG followed by single‐fiber SLAH between August 2014 and January 2022. Patients with causative hippocampal lesions apart from MTS or for whom the SLAH was considered palliative were excluded. An SOP catalogue was developed based on literature review. The dominant pattern for each patient was used for survival analysis. The primary outcome was 2‐year Engel I classification or recurrent seizures before then, stratified by SOP category. Results: Fifty‐eight patients were included, with a mean follow‐up duration of 39 ± 12 months after SLAH. Overall 1‐, 2‐, and 3‐year Engel I seizure freedom probability was 54%, 36%, and 33%, respectively. Patients with SOPs, including low‐voltage fast activity or low‐frequency repetitive spiking, had a 46% 2‐year seizure freedom probability, compared to 0% for patients with alpha or theta frequency repetitive spiking or theta or delta frequency rhythmic slowing (log‐rank test, p =.00015). Significance: Patients who underwent SLAH after stereo‐EEG had a low probability of seizure freedom at 2 years, but SOPs successfully predicted seizure recurrence in a subset of patients. This study provides proof of concept that SOPs distinguish between hippocampal seizure onset and spread and supports using SOPs to improve selection of SLAH candidates. [ABSTRACT FROM AUTHOR]

Purpose: The postoperative period after laser interstitial thermal therapy (LITT) is marked by a temporary increase in volume, which can impact the accuracy of radiographic assessment. The current criteria for progressive disease (PD) suggest that a 20% increase in size of brain metastasis (BM) assessed in 6–12 weeks intervals should be considered as local progression (LP). However, there is no agreement on how LP should be defined in this context. In this study, we aimed to statistically analyze which tumor volume variations were associated with LP. Methods: We analyzed 40 BM that underwent LITT between 2013 and 2022. For this study, LP was defined following radiographic features. A ROC curve was generated to evaluate volume change as a predictor of LP and find the optimal cutoff point. A logistic regression analysis and Kaplan Meier curves were performed to assess the impact of various clinical variables on LP. Results: Out of 40 lesions, 12 (30%) had LP. An increase in volume of 25.6% from baseline within 120–180 days after LITT presented a 70% sensitivity and 88.9% specificity for predicting LP (AUC: 0.78, p = 0.041). The multivariate analysis showed a 25% increase in volume between 120 and 180 days as a negative predictive factor (p = 0.02). Volumetric changes within 60–90 days after LITT did not predict LP (AUC: 0.57; p = 0.61). Conclusion: Volume changes within the first 120 days after the procedure are not independent indicators of LP of metastatic brain lesions treated with LITT. [ABSTRACT FROM AUTHOR]

ObjectiveThis study aimed to assess the safety and efficacy of MR-guided stereotactic laser ablation (SLA) therapy in the treatment of pediatric brain tumors.MethodsData from 17 North American centers were retrospectively reviewed. Clinical, technical, and radiographic data for pediatric patients treated with SLA for a diagnosis of brain tumor from 2008 to 2016 were collected and analyzed.ResultsA total of 86 patients (mean age 12.2 ± 4.5 years) with 76 low-grade (I or II) and 10 high-grade (III or IV) tumors were included. Tumor location included lobar (38.4%), deep (45.3%), and cerebellar (16.3%) compartments. The mean follow-up time was 24 months (median 18 months, range 3-72 months). At the last follow-up, the volume of SLA-treated tumors had decreased in 80.6% of patients with follow-up data. Patients with high-grade tumors were more likely to have an unchanged or larger tumor size after SLA treatment than those with low-grade tumors (OR 7.49, p = 0.0364). Subsequent surgery and adjuvant treatment were not required after SLA treatment in 90.4% and 86.7% of patients, respectively. Patients with high-grade tumors were more likely to receive subsequent surgery (OR 2.25, p = 0.4957) and adjuvant treatment (OR 3.77, p = 0.1711) after SLA therapy, without reaching significance. A total of 29 acute complications in 23 patients were reported and included malpositioned catheters (n = 3), intracranial hemorrhages (n = 2), transient neurological deficits (n = 11), permanent neurological deficits (n = 5), symptomatic perilesional edema (n = 2), hydrocephalus (n = 4), and death (n = 2). On long-term follow-up, 3 patients were reported to have worsened neuropsychological test results. Pre-SLA tumor volume, tumor location, number of laser trajectories, and number of lesions created did not result in a significantly increased risk of complications; however, the odds of complications increased by 14% (OR 1.14, p = 0.0159) with every 1-cm3 increase in the volume of the lesion created.ConclusionsSLA is an effective, minimally invasive treatment option for pediatric brain tumors, although it is not without risks. Limiting the volume of the generated thermal lesion may help decrease the incidence of complications.

Introduction: The surgical treatment of brain tumors has evolved over time, offering different strategies tailored to patients and their specific lesions. Among these strategies, Laser Interstitial Thermal Therapy (LITT) is one of the most recent advances in pediatric neurooncological surgery, and its results and evolution are still under assessment. Methods: We retrospectively analyzed data from six pediatric patients with deepseated brain tumors treated with LITT at a single center between November 2019 and June 2022. A total of four patients underwent a stereotaxic biopsy during the same operating session. The indications and preparation for LITT, technical issues, clinical and radiological follow-up, impact on quality of life, and oncological treatment are discussed. Results: The mean patient age eight years (ranging from 2 to 11 years). The lesion was thalamic in four patients, thalamo-peduncular in one, and occipital posterior periventricular in one. In total, two patients had been previously diagnosed with low-grade glioma (LGG). Biopsies revealed LGG in two patients, ganglioglioma grade I in one, and diffuse high-grade glioma (HGG) in one. Postoperatively, two patients presented with transient motor deficits. The mean follow-up period was 17 months (ranging from 5 to 32 months). Radiological follow-up showed a progressive reduction of the tumor in patients with LGG. Conclusion: Laser interstitial thermal therapy is a promising, minimally invasive treatment for deep-seated tumors in children. The results of lesion reduction appear to be relevant in LGGs and continue over time. It can be used as an alternative treatment for tumors located at sites that are difficult to access surgically or where other standard treatment options have failed. [ABSTRACT FROM AUTHOR]

Temporal lobe encephaloceles (TEs) are a rare cause of drug-resistant temporal lobe epilepsy (DR-TLE), with head trauma and obesity identified as risk factors in adults. This study evaluated the clinical characteristics of childhood-onset DR-TLE due to TE. This is a single-institution retrospective review of childhood-onset DR-TLE with radiographic TE identified between 2008 and 2020. The epilepsy history, brain imaging features, and surgical outcomes were collected. Eleven children with DR-TLE due to TE were included (median age at epilepsy onset was 11 years, interquartile range 8.5 to 13.5 years). Median latency between epilepsy diagnosis and TE detection was 3 years (range of 0 to 13 years). None had history of head trauma. Body mass index greater than 85 percentile for age and sex was seen in 36% of the children. No patient had bilateral TE identified. TEs were diagnosed based on epilepsy surgery conference re-review of imaging in 36% of cases. All herniations were contained defects without osseous dehiscence. Regional fluorodeoxyglucose (FDG) hypometabolism ipsilateral to the encephalocele was seen in all children who had FDG-positron emission tomography (PET) of the brain. Of the children who had surgery, 70% were seizure free or had nondisabling seizures at last follow-up (mean follow-up 52 months). TE is a surgically remediable etiology of DR-TLE in childhood. TEs are often overlooked at pediatric epilepsy diagnosis, calling for the need to increase awareness of this entity. FDG-PET temporal hypometabolism in children with presumed nonlesional DR-TLE should be carefully examined for occult TEs. [ABSTRACT FROM AUTHOR]

Introduction: Subependymal giant cell astrocytoma (SEGA) is the most common CNS tumor in patients with tuberous sclerosis complex (TSC). Although these are benign, their proximity to the foramen of Monroe frequently causes obstructive hydrocephalus, a potentially fatal complication. Open surgical resection has been the mainstay of treatment; however, this can cause significant morbidity. The development of mTOR inhibitors has changed the treatment landscape, but there are limitations to their use. Laser interstitial thermal therapy (LITT) is an emerging treatment modality that has shown promise in treatment of a variety of intracranial lesions, including SEGAs. We present a single institution, retrospective study of patients treated for SEGAs with LITT, open resection, mTOR inhibitors, or a combination of these modalities. The primary study outcome was tumor volume at most recent follow-up compared with volume at treatment initiation. The secondary outcome was clinical complications associated with treatment modality. Methods: Retrospective chart review was performed to identify patients with SEGAs treated at our institution from 2010 to 2021. Demographics, treatment information, and complications were collected from the medical record. Tumor volumes were calculated from imaging obtained at initiation of treatment and at most recent follow-up. Kruskal-Wallis nonparametric testing was used to assess differences in tumor volume and follow-up duration between groups. Results: Four patients underwent LITT (3 with LITT only), three underwent open surgical resection, and four were treated with mTOR inhibitors only. Mean percent tumor volume reduction for each group was 48.6 ± 13.8, 90.7 ± 39.8, and 67.1 ± 17.2%, respectively. No statistically significant difference was identified comparing percent tumor volume reduction between the three groups (p = 0.0513). Additionally, there was no statistically significant difference in follow-up duration between groups (p = 0.223). Only 1 patient in our series required permanent CSF diversion and 4 discontinued or decreased the dose of mTOR inhibitor due to either cost or side effects. Conclusions: Our study suggests that LITT could be considered as a treatment option for SEGAs as it was effective in reducing tumor volume with very few complications. This modality is less invasive than open resection and may be an alternative for patients who are not candidates for mTOR inhibitors. We recommend an updated paradigm for SEGA treatment which includes LITT in select cases after consideration of patient-specific factors. [ABSTRACT FROM AUTHOR]

Laser interstitial thermal therapy (LITT) is an emerging clinical treatment for deep brain tumors, which is safe, minimally invasive, and effective. This paper established a three-dimensional model based on the LITT heat transfer model, including brain tissue, laser fiber, and straight tube vessels. Combining the PID control equation, diffuse approximation equation, Pennes heat transfer equation, and Murray's law, the effect of micro-vessel radius and distance between vessels and fiber on the ablation temperature field during laser ablation was investigated by using COMSOL finite element software. The results showed that at a constant distance of 1 mm between the vessel and the fiber, the vessels with a radius of 0.1–0.2 mm could be completely coagulated, the vessels with a radius of 0.3–0.6 mm had cooling and directional effects on temperature distribution and thermal damage, and the vessels with a radius of 0.7–1.0 mm had cooling effects on the ablation temperature. When the vessel-fiber spacing was raised by 2 mm, 0.3–0.4 mm, vasculature had a directional influence on the temperature field; when the vessel-fiber spacing was raised by 3 mm, only 0.3 mm vessels had a directional effect on the temperature field. The range of temperature field impacted by blood flow diminishes as the distance between the optical fiber and the blood artery grows. The ablation zone eventually tends to be left and right symmetrical. In this study, we simulated the LITT ablation temperature field model influenced by tiny vessels based on PID control. We initially classified the vessels, which provided some guidance for accurate prediction and helped the accuracy of preoperative planning. [ABSTRACT FROM AUTHOR]

Purpose: Nearly a quarter of neurofibromatosis type 1 (NF 1)- associated diencephalic low-grade tumors are refractory to chemotherapy. Addition of alternative treatment options with laser interstitial thermal therapy will have a positive impact on the outcome of these patients. Methods: We report on two illustrated cases of pediatric NF1- associated, chemoresistant, WHO grade 1 pilocytic astrocytomas treated with laser interstitial thermal therapy (LITT). Results: Both tumors responded favorably to LITT. Conclusion: LITT should be considered as a treatment option for chemoresistant deep-seated NF1-associated low-grade gliomas. [ABSTRACT FROM AUTHOR]