Objective: The objective of this study was to develop a murine system for the delivery of laser interstitial thermotherapy (LITT) with probe-based thermometry as a model for human glioblastoma treatment to investigate thermal diffusion in heterogeneous brain tissue.
Methods: First, the tissue heating properties were characterized using a diode-pumped solid-state near-infrared laser in a homogeneous tissue model. The laser was adapted for use with a repurposed stereotactic surgery frame utilizing a micro laser probe and Hamilton syringe. The authors designed and manufactured a stereotactic frame attachment to work as a temperature probe stabilizer. Application of this novel design was used as a precise method for real-time thermometry at known distances from the thermal ablative center mass during murine LITT studies.
Results: Temperature measurements were achieved during LITT that verified the direct thermometry capability of the system without the need for MR-based thermal monitoring. Application of multiple stereotactic design iterations led to an accurately reproducible surgical laser ablation procedure. Histological staining confirmed precise thermal ablation and controllable lesion size based on time and temperature control. Treatment of a syngeneic intracranial glioma model highly resistant to conventional therapy resulted in a modest survival benefit.
Conclusions: The authors have successfully developed a murine model system of LITT with direct in situ thermometry for investigation into the effects of thermal ablation and combinatorial treatments in murine brain tumor models.
Objective: Laser interstitial thermal therapy (LITT) is a minimally invasive procedure used to ablate abnormal tissue in a targeted fashion. It is most commonly used to treat epileptic foci, brain tumors, and radiation necrosis. This study aimed to compare immediate postoperative outcomes between these indications.
Methods: This study analyzed clinical data from the Nationwide Readmissions Database (NRD) from 2016 to 2019 and identified 2234 patients who underwent LITT procedures using ICD-10 codes. The authors analyzed patient demographics, complications, discharge disposition, readmission rates, and mortality. Following propensity score matching, 317 patients treated for epilepsy and 323 patients treated for brain tumors were compared.
Results: The mean ages were similar (epilepsy: 45.7 vs tumor: 49.0 years, p = 0.55), as were the proportions of female patients (epilepsy: 45.4% vs tumor: 52.9%, p = 0.83), all-payer costs (p = 0.81), income quartiles (p = 0.58), insurance types (p = 0.70), frailty rates (p = 0.85), and comorbid disease burdens as assessed by ECI score (p = 0.73). No significant differences were observed in rates of hemorrhage (p = 0.1), pulmonary embolism (p = 0.32), or infection (p = 0.16). However, the tumor cohort had higher rates of deep vein thrombosis (3.4% vs < 3.15%, p = 0.045), nonroutine discharge (26.6% vs 16.4%, p = 0.04), and 1-year hospital readmission (32.5% vs 18.6%, p = 0.006). One-year mortality rates were similar (tumor: 3.4% vs epilepsy: < 3.15%, p = 0.08).
Conclusions: While postoperative complications and 1-year mortality rates were similar among patients undergoing LITT for epilepsy and brain tumors, the tumor cohort experienced higher rates of deep vein thrombosis, nonroutine discharge, and 1-year hospital readmission.
Objective: Laser interstitial thermal therapy (LITT) is an emerging tool for treating a variety of focal brain lesions, including recurrent high-grade glioma (HGG). While the efficacy and uses of LITT have been well studied, the impact of this treatment on patient functional outcomes has not been analyzed in detail. This study sought to better define the role of LITT in treating patients with recurrent HGG, examining which patients exhibit good functional outcomes after LITT, and to determine risk factors for worsening neurological function.
Methods: The medical records of patients treated with LITT for recurrent HGG at a single tertiary care center were retrospectively reviewed. Functional status was assessed using the Karnofsky Performance Scale (KPS). Demographic, clinical, and radiological data were examined for associations with change in KPS score assessed 4-6 weeks following surgery.
Results: Forty-seven patients were included in the study with histopathologically confirmed recurrent HGG. The mean age was 57 years, and 21 (45%) patients were female. The pre-LITT KPS scores were as follows: 100 in 4 (9%) patients, 90 in 15 (32%) patients, 80 in 10 (21%) patients, 70 in 13 (28%) patients, and 60 in 5 (11%) patients. Overall, 59% of patients showed a stable or improved KPS score after undergoing LITT. Tumor volume was the sole predictor of decreased KPS score after LITT. Notably, tumor location including eloquent location, preoperative KPS score, and other comorbidities were not independently associated with change in functional status.
Conclusions: The majority of patients undergoing LITT for recurrent HGG had a favorable functional outcome at the initial follow-up visit. The treated tumor volume was inversely and independently associated with post-LITT functional outcome. This information may help guide patient selection and treatment optimization in the setting of LITT-based approaches for recurrent HGG.
Objective: Maximizing safe resection in neuro-oncology has become paramount to improving patient survival and outcomes. Laser interstitial thermal therapy (LITT) offers similar survival benefits to traditional resection, alongside shorter hospital stays and faster recovery times. The extent of ablation (EOA) achieved using LITT is linked to patient outcomes, with greater EOA correlating with improved outcomes. However, the preoperative predictors for achieving supramaximal ablation (EOA ≥ 100%) are not well understood. By leveraging machine learning (ML) techniques, this study aimed to identify these predictors to enhance patient selection and therefore outcomes. The objective was to explore preoperative predictors for supramaximal EOA using ML in patients with glioblastoma.
Methods: A retrospective study was conducted on the medical records of 254 patients undergoing LITT from 2013 to 2023 at a single tertiary center. Cohort criteria included age ≥ 18 years, diagnosis of glioblastoma, single-trajectory ablation, and a complete dataset. The study assessed preoperative clinical and radiographic factors, using EOA ≥ 100% as the endpoint. Five ML models were used: logistic regression, random forest (RF), gradient boosting, Gaussian naive Bayes, and support vector machine. Training and testing cohorts were subsequently assessed across ML models with fivefold cross-validation. Models were optimized using hyperparameter tuning. Performance was primarily quantified using the area under the curve (AUC) of the receiver operating characteristic curve.
Results: The final cohort consisted of 72 patients. Among the ML models, RF achieved the highest AUC (mean ± SD 0.94 ± 0.06). The leading models identified that lower preoperative volume, history of prior radiation therapy, history of prior craniotomy, preoperative neurological deficits, history of preoperative seizures, and distance from intracranial heat sinks were predictive of successful ablations in patients. Additionally, RF had the best mean metrics: accuracy 0.88, precision 0.87, specificity 0.87, and sensitivity 0.89.
Conclusions: This is the first study to investigate the role of ML for optimizing ablation volumes in LITT. These ML models suggest that low preoperative volumes, previous craniotomy, previous radiation therapy, no previous neurological deficits, larger catheter-heat sink distance, and the presence of preoperative seizures are important prognostic factors for predicting successful supramaximal ablations with LITT.
Objective: Laser interstitial thermal therapy (LITT) has emerged as an alternative for treating glioblastoma (GBM) in patients deemed unsuitable for resection due to deep-seated or eloquent location, age, or comorbidities. However, its safety and efficacy in large-volume, deep-seated, newly diagnosed GBM (nGBM) tumors remain insufficiently studied. Therefore, the authors aimed to assess the outcomes of LITT in the treatment of deep-seated, large-volume nGBM.
Methods: A retrospective analysis of patients with nGBM who underwent LITT between February 2013 and August 2023 was conducted. Patients with deep-seated tumor volume ≥ 10 cm3 treated with LITT were compared to patients with deep-seated tumor volume < 10 cm3. Demographic, perioperative, and follow-up data were collected and compared among both groups. Kaplan-Meier survival analysis and Cox proportional hazards regression were performed to evaluate the impact of various clinical and treatment-related factors on patient survival.
Results: A total of 33 patients in the study group (mean ± SD age 65.7 ± 10.2 years, 58% male) with mean tumor volume 36.0 ± 21.6 cm3 were compared to 23 controls (mean age 67.0 ± 12.5 years, 61% male) with mean tumor volume 5.2 ± 2.7 cm3. There were no significant differences in hospital length of stay (p = 0.494), temporary neurological deficits and edema within 30 days (p = 0.705 and p > 0.999, respectively), 30-day readmissions (p = 0.139), < 30-day complications (p = 0.918), complications between 30 days and 3 months (p = 0.903), and new motor and speech deficits within 3 months (p = 0.883 and p > 0.999, respectively) between the study and control groups. Kaplan-Meier analysis did not reveal any statistically significant difference in overall survival (OS) between groups (p = 0.227). Multivariate analysis indicated that tumor volume did not significantly affect the hazard ratio for individuals undergoing LITT (HR 1.16, 95% CI 0.83-3.29, p = 0.150).
Conclusions: This pilot study suggests that LITT is safe for treating patients with large-volume, deep-seated nGBM compared to those with small-volume tumor. Although there appears to be improved OS in patients with smaller lesions with greater EOA, significance was not achieved in this cohort.
Objective: Holmes tremor (HT) is a complex syndrome characterized by resting, postural, and kinetic tremors. HT significantly impacts patients' quality of life (QOL) and daily activities. Conventional pharmacological treatments for HT often yield inconsistent results. Emerging surgical treatments such as deep brain stimulation and various thalamotomy techniques show promise but come with challenges, including adverse events (AEs) and potential tremor recurrence. This study aimed to evaluate the clinical outcomes of unilateral MRI-guided laser interstitial thermal therapy (MRIgLITT) thalamotomy in patients with medically intractable HT, focusing on tremor reduction, QOL, and AE incidence, and provide a comprehensive review of the literature on thalamotomy techniques for HT.
Methods: Five patients with medically intractable HT underwent unilateral MRIgLITT thalamotomy between June 2020 and January 2023. Tremor severity was assessed using the Fahn-Tolosa-Marin Tremor Rating Scale (TRS) at baseline and at 3 and 12 months postoperatively. QOL was measured using the Quality of Life in Essential Tremor (QUEST) questionnaire and 39-item Parkinson's Disease Questionnaire (PDQ-39). Subjective patient-rated improvement was evaluated using the Patient Global Impression of Clinical Status (PGI-C) scale at 12 months. Cognitive performance was assessed using the Mini-Mental State Examination (MMSE) before the procedure and at 12 months postoperatively. AEs were monitored throughout the follow-up period.
Results: The mean patient age was 50.2 ± 22.37 years, with a mean tremor duration of 5.8 ± 4.55 years. Significant tremor reduction was observed in the treated hand, with mean TRS scores decreasing from 19.00 ± 4.36 at baseline to 11.20 ± 4.44 (p = 0.043) at 3 months and 13.40 ± 5.94 (p = 0.042) at 12 months, indicating a relative reduction of 41.05% and 29.47%, respectively. A significant effect was observed on the QUEST scale at 3 months (p = 0.043), but this effect was no longer present at 12 months. No significant effect was found on the PDQ-39 QOL scale. The PGI-C scale showed a high mean subjective improvement of 88.60% ± 8.36% at 12 months. One patient experienced severe AEs, including dysarthria, hemiparesis, and swallowing difficulties, which required prolonged hospitalization and multidisciplinary rehabilitation, but regressed within 3 months. Cognitive performance, as measured by the MMSE, remained stable (p = 0.785).
Conclusions: Unilateral MRIgLITT thalamotomy showed promise as a treatment for medically intractable HT, providing significant tremor reduction with a favorable safety profile. However, the potential for tremor recurrence and minimal functional improvement in fine motor skills highlight the need for long-term follow-up and further research. Larger, multicenter studies are necessary to validate these findings.
Objective: Laser interstitial thermal therapy (LITT) is a minimally invasive procedure that allows cytoreduction of brain tumors and can be considered as an alternative to craniotomy. The authors surveyed 27 patients who underwent both craniotomy and LITT during distinct stages of their oncology journey to assess patient-reported outcomes comparing both procedures.
Methods: A 9-question survey was developed and validated to assess patient-reported postoperative recovery, pain level, narcotic use, and procedure preference. The survey was administered to patients with WHO grade II-IV gliomas who underwent both craniotomy and LITT.
Results: The survey was reviewed by independent surgeons, patient advocates, and patients for face validity and showed > 90% intrarater agreement over time. The cohort had a mean age of 57 ± 12 years, and 78% had glioblastoma. There was no significant difference in symptomatic improvement postcraniotomy or post-LITT (30% vs 4%, p = 0.17). Similarly, no significance was detected in patient-reported recovery time from craniotomy (time required to return to preoperative state: mean 4.3 ± 9.1 weeks, median 2 weeks) or LITT (mean 2 ± 2.3 weeks, median 1 week; p = 0.21). Notably, postsurgical pain (0-10 on the visual analog scale) and need for narcotic use in the first week (yes/no) after the procedure were significantly lower post-LITT (average visual analog scale score 1.7 vs 5 points, narcotic use 4% vs 81%; p < 0.0001 for both comparisons). When asked which procedure they would choose-having experienced both craniotomy and LITT-surveyed patients overwhelmingly chose LITT over craniotomy (89% vs 11%, p < 0.0001). Of note, the patients who preferred craniotomy experienced improved neurological function postcraniotomy or suffered new deficits post-LITT.
Conclusions: In this pilot study, patients reported less pain and narcotic use post-LITT relative to craniotomy and generally preferred the former procedure if given the choice. Validation of these results in future studies can help inform decision-making in clinical scenarios where there is equipoise between LITT and craniotomy.