Clinical UM Guideline

This document addresses minimally invasive ablative procedures used in the treatment of medically refractory epilepsy in individuals with symptomatic localized epilepsy. Minimally invasive procedures have been proposed as a means to minimize or eliminate major craniotomy and bone flap incisions, decrease pain and down-time, preserve tissue and decrease neurocognitive adverse effects. These procedures utilize laser, radiofrequency, or cryotherapy techniques, in combination with stereotactic magnetic resonance imaging (MRI) guidance, for targeted ablation of the epileptogenic foci.

Note: This document does not address minimally invasive surgery to treat conditions other than epilepsy, including treatment of cancerous lesions.

Note: Please see the following related documents for additional information:

• CG-ANC-03 Acupuncture
• CG-MED-05 Ketogenic Diet for Treatment of Intractable Seizures
• MED.00057 MRI Guided High Intensity Focused Ultrasound Ablation for Non-Oncologic Indications
• SURG.00026 Deep Brain, Cortical, and Cerebellar Stimulation
• CG-SURG-61 Cryosurgical, Radiofrequency, Microwave or Laser Ablation to Treat Solid Tumors Outside the Liver

Medically Necessary:

The treatment of medically refractory epilepsy using stereotactic laser techniques (MRI-guided laser interstitial thermal ablation [MRIgLITT]), including stereotactic laser amygdalohippocampotomy (SLAH), is considered medically necessary when both of the following criteria are met:

1. Documented disabling seizures despite the use of two or more tolerated antiepileptic drug regimens; and
2. Documented presence of two or fewer well delineated epileptogenic foci accessible by laser.

The use of stereotactic radiofrequency thermocoagulation (RF-TC) in the treatment of hypothalamic hamartomas is considered medically necessary.

Not Medically Necessary:

The treatment of medically refractory epilepsy using stereotactic laser techniques or stereotactic radiofrequency thermocoagulation is considered not medically necessary when the criteria above have not been met.

Other minimally invasive procedures to treat medically intractable epilepsy are considered not medically necessary, including but not limited to stereotactic radiofrequency amygdalohippocampectomy, sEEG-guided radiofrequency thermocoagulation or stereotactic cryosurgery.

The following codes for treatments and procedures applicable to this guideline are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services may be Medically Necessary when criteria are met:

When services are Not Medically Necessary:
For the procedure and diagnosis codes listed above when criteria are not met, or when the code describes a procedure designated in the Clinical Indications section as not medically necessary.

When services are also Not Medically Necessary:

Summary

Two minimally invasive ablation options have supportive evidence for drug‑resistant focal epilepsy. Magnetic resonance imaging (MRI) guided laser interstitial thermal therapy (MRgLITT) yields seizure freedom in about 55 to 60% of well‑localized cases and shows lower major complication rates and better cognitive preservation than open resection. This benefit is highest for lesional foci and lower for nonlesional or network‑based disease. Stereoelectroencephalography (SEEG) guided radiofrequency thermocoagulation (RFTC) is mainly diagnostic or palliative outside hypothalamic hamartoma (HH), with typical 12‑month responder rates near 50% and low durable seizure‑free proportions. In HH, SEEG‑guided disconnection functions as definitive therapy, with gelastic seizure freedom around 80% or higher.

Discussion

The burden of epilepsy and the treatment landscape

During 2021-2022, about 2.9 million U.S. adults had active epilepsy; about 456,000 U.S. children also had active epilepsy (Centers for Disease Control and Prevention [CDC], 2024). Active epilepsy is defined as being physician-diagnosed and having had one or more seizures in the past year or taking medication to control it, or both (CDC, 2024). Mesial temporal lobe epilepsy (MTLE) is common, representing approximately one-quarter of all cases; one-third of these individuals are considered medication refractory (Gross, 2018). The International League against Epilepsy defines drug-resistant epilepsy (DRE) as the:

"failure of adequate trials of two tolerated and appropriately chosen and used AED schedules (whether as monotherapies or in combination) to achieve sustained seizure freedom" (Kwan, 2010).

Note: the International League Against Epilepsy (ILAE) statement refers to antiepileptic drugs (AEDs). This document refers to the same drugs as antiseizure medications (ASMs).

After failure of two appropriately chosen ASMs, the additional chance of seizure freedom with a third regimen is about 4%, and very few patients attain seizure freedom with further regimens (Chen, 2018).

While pharmacotherapy is the first line of treatment, it does not achieve complete seizure control in about one-third of individuals (LaRiviere, 2016). For this population, open procedures such as anterior temporal lobectomy (ATL) or selective amygdalohippocampectomy (sAHE) have been the gold standard, involving localizing and excising the epileptogenic zones (Shukla, 2017). These open procedures typically report a 60-80% long-term seizure-free rate (Chang, 2015; Kang, 2016). However, concerns about invasiveness and the effect on neuropsychological function have limited utilization; approximately 2% of eligible candidates undergo open surgery annually (Kang, 2016). In device neuromodulation, responsive neurostimulation (RNS) shows a median 75% seizure reduction at 9 years with a 73% responder rate (Nair, 2020).

Overview of minimally invasive therapies

The limitations of open surgery have driven the exploration of minimally invasive therapies. These therapies are proposed as viable options for those with epileptogenic foci located near deep, eloquent brain regions, or those who are poor surgical candidates (Shukla, 2017). Minimally invasive ablation has two primary evidence-based roles in DRE. MRgLITT is an effective definitive option when a well-defined epileptogenic focus or critical propagation pathway is localized and technically accessible. SEEG-guided RFTC functions primarily as a diagnostic or palliative bridge in most focal epilepsies but serves as a definitive therapy in HH where disconnection is feasible.

Technology descriptions

Laser interstitial thermal therapy (LITT)

Stereotactic LITT, typically MRI-guided, uses low-voltage laser energy delivered via optical fiber through a burr hole to destroy targeted tissue while minimizing injury to surrounding tissue. MRgLITT consists of three elements: stereotactic techniques for exact positioning, the use of the laser to provide time-dependent thermal tissue ablation, and MRI thermography to provide real-time monitoring of temperature and tissue destruction (Dorfer, 2020). Laser energy is converted to thermal energy, leading to coagulative necrosis. Real-time MRI guidance allows for monitoring of both the device tip and thermal damage (Gross, 2016; Shukla, 2017). When used for MTLE, the procedure is often referred to as stereotactic laser amygdalohippocampotomy (SLAH).

However, LITT is not without drawbacks. Ablative therapies do not allow for tissue to be obtained for pathology, and technical limitations exist. As noted by Kang (2016), “The curvature of the hippocampus and the presence of potential heat sinks (i.e., blood and cerebrospinal fluid (CSF)) may prevent adequate ablation of the epileptogenic network in some individuals.”

There are three U.S. Food and Drug Administration (FDA) cleared MRgLITT systems. The Visualase thermal therapy system (Medtronic) received initial FDA 510(k) clearance for the cooled applicator system in 2006 (K053087), with subsequent system clearance in 2007 (K071328); it has been used to treat epilepsy since 2012 (Kang, 2016). The NeuroBlate System (Monteris Medical) received initial 510(k) clearance in 2013 (K131278); a 2024 clearance explicitly lists epileptogenic foci in the indications (K240877). The Tranberg Thermoguide Therapy System (Clinical Laserthermia Systems) received 510(k) clearance in 2022 (K214125).

Radiofrequency thermocoagulation (RFTC)

SEEG-guided RFTC, also called thermo-SEEG, involves the use of implanted SEEG electrodes to both identify the location of seizure-onset zones and to perform multiple stereotactic lesioning of the identified areas. It is proposed as an alternative when resective surgery is not feasible, such as when the zone is located in a highly functional area (Moles, 2018). Advantages include accurate targeting based on intracranial recordings, the ability to perform multiple lesions, and the capacity for functional mapping via electrical stimulation prior to lesioning to anticipate adverse effects (Moles, 2018).

Evidence analysis: MRgLITT

Guidelines and overall efficacy

The American Society for Stereotactic and Functional Neurosurgery (ASSFN) position statement supports MRgLITT for DRE with well-defined, accessible foci and reports safety and efficacy consistent with open series (ASSFN, 2022).

Prospective multicenter data on MTLE report Engel class I (free from disabling seizures) outcomes in about 58% at two years, with parallel improvements in quality-of-life metrics (Landazuri, 2025). Meta-analyses generally converge near this 55-60% Engel class I range. A systematic review and meta-analysis by Alomar and colleagues (2023), analyzing data from 836 individuals in 21 studies, found an overall Engel class I outcome in 56% of individuals (95% confidence interval (CI), 52.4-59.5%) at last follow-up. Other analyses confirm these findings, reporting similar overall prevalence of Engel class I outcomes (Barot, 2021; Xue, 2018).

Outcomes vary by etiology. MRgLITT is particularly effective in treating individuals with well-circumscribed lesional DRE. A meta-analysis of 450 individuals found that cerebral cavernous malformation (CCM) and mesial temporal sclerosis/atrophy (MTS/A) were independently associated with greater odds of seizure freedom, while MRgLITT was less effective in nonlesional cases or those with a more diffuse epileptogenic network (Chen, 2023).

Comparison with open resection

When compared with open resection (e.g., ATL or sAHE), pooled analyses indicate that resection achieves higher seizure-free rates. Alomar (2023) found that outcomes after MRgLITT (56%) were slightly inferior to temporal lobectomy (66%). Similarly, a comparative meta-analysis including over 3500 individuals compared outcomes across different follow-up periods. Engel class I outcomes were achieved after MRgLITT in 57% (follow-up range 6 to 70 months), compared to ATL in 69% and sAHE in 66% (follow-up range 12 to 116.4 months) (Kohlhase, 2021).

Kohlhase and colleagues (2021) noted that participants receiving ATL or sAHE had significantly better outcomes, particularly at follow-up of 60 months or more. However, they observed a large difference in the range of follow-up periods between the groups. In a subgroup analysis for participants with follow-up less than 60 months, the difference in seizure outcomes was nonsignificant between MRgLITT and ATL (p=0.057) or sAHE (p=0.28), highlighting that comparable long-term data for MRgLITT are not yet available (Kohlhase, 2021).

Safety and cognitive outcomes

While efficacy may be marginally lower, MRgLITT demonstrates a favorable safety profile and cognitive advantages, with mostly mild or transient adverse events reported in prospective data (Landazuri, 2025). The overall complication rate for MRgLITT is reported around 19-20% (Alomar, 2023; Barot, 2021). Major complication rates were lower for MRgLITT (3.8%) than for ATL (10.9%) or sAHE (7.4%) (Kohlhase, 2021). The most common adverse event is visual field deficits, with other events including intracranial hemorrhage and motor deficits (Barot, 2021).

Furthermore, MRgLITT offers better preservation of neuropsychological function. Gross and colleagues (2018) evaluated outcomes of 58 individuals undergoing SLAH, reporting that 8.2% experienced decline in verbal memory, compared to rates of 30-60% decline reported for open resection. The cognitive benefits and safety profile make SLAH an attractive alternative, especially when considering surgery on the dominant hemisphere (Gross, 2018; Kang, 2016). Most MRgLITT series enroll well-localized focal epilepsy; applicability to multifocal disease is limited by selection. Several studies report procedures involving multiple ablation sites with favorable outcomes. These studies involved multiple ablation trajectories within single epileptogenic networks rather than treatment of multiple independent seizure sources. No studies were designed to evaluate outcomes by number of independent foci or provide comparative data demonstrating equivalent safety and efficacy beyond two distinct sources (Ravindra, 2023a; Ravindra, 2023b; Slegers. 2024).

Evidence analysis: SEEG-guided RFTC (outside HH)

The evidence suggests RFTC outside of HH functions primarily as a diagnostic or palliative tool rather than a definitive treatment. Contemporary data indicate RFTC is safe and produces short-term responder rates near 50% in mixed focal cohorts, but durable seizure freedom before additional therapy is uncommon (Vasquez, 2025). A systematic review and meta-analysis of RFTC involving 360 participants found a favorable seizure outcome (Engel class I/II) in 62% of cases with at least 12 months of follow-up (Kerezoudis, 2022).

However, studies measuring complete seizure freedom show rates diminish rapidly over time. In a prospective evaluation of 162 individuals, 25% were seizure-free at 2 months, but this dropped to only 7% at 12 months; responder rates (≥50% reduction in seizure frequency) were 48% at 12 months (Bourdillon, 2017).

RFTC outcomes are significantly worse than other surgical options. A meta-analysis assessing MRgLITT and SEEG-guided RFTC in 804 participants (minimum follow-up 6 months) reported that those treated with MRgLITT had a significantly (p<0.001) greater overall rate of freedom from seizures (65%) compared to SEEG-guided RFTC (23%), likely related to the sizes of the ablated lesions (Wang, 2020). Similarly, a retrospective comparison with ATL in temporal lobe epilepsy reported that at 12 months, none of the RFTC group (n=21) were seizure-free, while 75.5% of the ATL group (n=49) were; most of the RFTC group subsequently underwent ATL (Moles, 2018). This pattern supports the use of RFTC outside HH primarily as a step that informs candidacy for subsequent definitive surgery or neuromodulation.

Hypothalamic hamartomas (HH)

HH is a rare congenital ventral hypothalamus malformation (estimated 1 in every 200,000 individuals) that often results in drug-resistant epilepsy, commonly presenting as intractable gelastic seizures (Kerrigan, 2017; Kameyama, 2016). Gelastic seizures typically do not respond to pharmacotherapy. The location of HH lesions near the midline of the skull base makes them difficult to reach with microsurgical approaches; these approaches are invasive and associated with higher morbidity and lower success rates (5-60%) (Kameyama, 2016; Tandon, 2018a).

For HH, minimally invasive disconnection with MRgLITT or stereotactic RFTC (SRT) is the preferred approach and has largely supplanted open approaches. Both laser and SRT trials have reported outcomes superior to microscopic surgery with limited morbidity (Curry, 2018; Iranmehr, 2022; Tandon, 2018a; Rizzi, 2023). Kameyama and colleagues (2016) reported on 100 consecutive individuals treated with MRI-guided SRT (follow-up between 1 and 17 years), noting that 86% achieved freedom from gelastic seizures. Recent long-term reports show sustained seizure freedom with SEEG-optimized RFTC and identify ablation of the hamartoma and its attachment as independent predictors of outcome, reinforcing a strategy focused on disconnection rather than debulking (Dai, 2025).

In addition to treating seizures, these procedures are associated with improvement in epileptic encephalopathy symptoms (cognitive impairment and behavioral disorders). Individuals who achieved gelastic seizure remission following SRT (average follow-up 3.3 years) had a significant postoperative improvement in full-scale intelligence quotient (FSIQ) scores (p<0.001), whereas those without remission did not (Sonoda, 2017).

Anterior temporal lobectomy (ATL): Surgical resection of the of mesial-basal temporal lobe structures. A limitation of ATL is that access to these structures requires resection of the temporal neocortex which affects cognitive and neuropsychological abilities.

Engel Classification: A system used to classify outcomes after epilepsy surgery based on the degree to which seizures are reduced.

• Engel Class 1: seizure free (100% reduction)
• Engel Class II: Rare disabling seizures, or less than three seizure days per year
• Class III: Worthwhile improvement, or more than an 80% reduction in seizure frequency
• Class IV: No worthwhile improvement, or less than an 80% reduction in seizure frequency

Epilepsy: A disease of the brain when any of the following conditions occur:

• At least two unprovoked (or reflex) seizures occurring > 24 h apart
• One unprovoked, or reflex, seizure and a probability of further seizures similar to the general recurrence risk (at least 60%) after two unprovoked seizures, occurring over the next 10 years
• Diagnosis of an epilepsy syndrome

Gelastic seizure (GS): a seizure characterized by outbursts of uncontrolled inappropriate laughter or giggling. This seizure type is most commonly associated with hypothalamic hamartoma.

Medically intractable epilepsy: The failure of at least two separate drug regimens to control seizure activity; also known as drug resistant epilepsy.

SEEG: stereoelectroencephalography-guided radiofrequency thermocoagulation, a minimally invasive treatment that uses stereotactically-directed electrodes to deliver radiofrequency energy to ablate epileptogenic foci.

Selective amygdalohippocampectomy (SAH): Surgical resection of mesial-basal temporal lobe structures which does not involve neocortical resection.

Peer Reviewed Publications:

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38. Moles A, Guénot M, Rheims S, et al. SEEG-guided radiofrequency coagulation (SEEG-guided RF-TC) versus anterior temporal lobectomy (ATL) in temporal lobe epilepsy. J Neurol. 2018; 265(9):1998-2004.
39. Nair DR, Laxer KD, Weber PB, et al. Nine-year prospective efficacy and safety of brain-responsive neurostimulation for focal epilepsy. Neurology. 2020; 95(9):e1244-e1256.
40. Ogasawara C, Watanabe G, Young K, et al. Laser interstitial thermal therapy for cerebral cavernous malformations: a systematic review of indications, safety, and outcomes. World Neurosurg. 2022; 166:279-287.
41. Patel P, Patel NV, Danish SF. Intracranial MR-guided laser-induced thermal therapy: single-center experience with the Visualase thermal therapy system. J Neurosurg. 2016; 125(4):853-860.
42. Perry MS, Donahue DJ, Malik SI, et al. Magnetic resonance imaging-guided laser interstitial thermal therapy as treatment for intractable insular epilepsy in children. J Neurosurg Pediatr. 2017; 20(6):575-582.
43. Ravindra VM, Ruggieri L, Gadgil N, et al. An initial experience of completion hemispherotomy via magnetic resonance-guided laser interstitial therapy. Stereotact Funct Neurosurg. 2023;101(3):179-187. doi:10.1159/000528452 (a).
44. Ravindra VM, Karas PJ, Lazaro TT, et al. Epilepsy surgery in young children with tuberous sclerosis complex: a novel hybrid multimodal surgical approach. Neurosurgery. 2023; 92(2):398-406 (b).
45. Rizzi M, Nichelatti M, Ferri L, et al. Seizure outcomes and safety profiles of surgical options for epilepsy associated to hypothalamic hamartomas. A systematic review and meta-analysis. Epilepsy Res. 2023; 198:107261.
46. Shukla ND, Ho AL, Pendharkar AV, et al. Laser interstitial thermal therapy for the treatment of epilepsy: evidence to date. Neuropsychiatr Dis Treat. 2017; 13:2469-2475.
47. Slegers R, Wagner L, van Kuijk S, et al. Stereo-electroencephalography-guided radiofrequency thermocoagulation restricted to periventricular nodular heterotopias in patients with drug-resistant epilepsy: a single center experience. Seizure. 2024; 121:105-113.
48. Sonoda M, Masuda H, Shirozu H, et al. Predictors of cognitive function in patients with hypothalamic hamartoma following stereotactic radiofrequency thermocoagulation surgery. Epilepsia. 2017; 58(9):1556-1565.
49. Southwell DG, Birk HS, Larson PS, et al. Laser ablative therapy of sessile hypothalamic hamartomas in children using interventional MRI: report of 5 cases. J Neurosurg Pediatr. 2018; 21:460-465.
50. Spencer D, Burchiel K. Selective amygdalohippocampectomy. Epilepsy Res Treat. 2012; 2012:382095.
51. Tandon V, Chandra PS, Doddamani RS, et al. Stereotactic radiofrequency thermocoagulation of hypothalamic hamartoma using robotic guidance (ROSA) coregistered with O-arm guidance-preliminary technical note. World Neurosurg. 2018a; 112:267-274
52. Tandon V, Lang M, Chandra PS, et al. Is edema a matter of concern after laser ablation of epileptogenic focus? World Neurosurg. 2018b; 113:366-372.e3.
53. Tao JX, Wu S, Lacy M, et al. Stereotactic EEG-guided laser interstitial thermal therapy for mesial temporal lobe epilepsy. J Neurol Neurosurg Psychiatry. 2018; 89(5):542-548.
54. Vasquez A, Islam K, Cross MR, et al. Radiofrequency thermocoagulation in focal epilepsy: a retrospective cohort study. Epilepsia Open. 2025; 10(2):529-538.
55. Wang R, Beg U, Padmanaban V, et al. A systematic review of minimally invasive procedures for mesial temporal lobe epilepsy: too minimal, too fast? Neurosurgery. 2021; 89(2):164-176.
56. Wang Y, Xu J, Liu T, et al. Magnetic resonance-guided laser interstitial thermal therapy versus stereoelectroencephalography-guided radiofrequency thermocoagulation for drug-resistant epilepsy: a systematic review and meta-analysis. Epilepsy Res. 2020; 166:106397.
57. Waseem H, Osborn KE, Schoenberg MR, et al. Laser ablation therapy: an alternative treatment for medically resistant mesial temporal lobe epilepsy after age 50. Epilepsy Behav. 2015; 51:152-157.
58. Waseem H, Vivas AC, Vale FL. MRI-guided laser interstitial thermal therapy for treatment of medically refractory non-lesional mesial temporal lobe epilepsy: outcomes, complications, and current limitations: a review. J Clin Neurosci. 2017; 38:1-7.
59. Wei PH, An Y, Fan XT, et al. Stereoelectroencephalography-guided radiofrequency thermocoagulation for hypothalamic hamartomas: preliminary evidence. World Neurosurg. 2018; 114:e1073-e1078.
60. Wilfong AA, Curry DJ. Hypothalamic hamartomas: optimal approach to clinical evaluation and diagnosis. Epilepsia. 2013; 54(Suppl 9):109-114.
61. Willie JT, Laxpati NG, Drane DL, et al. Real-time magnetic resonance-guided stereotactic laser amygdalohippocampotomy for mesial temporal lobe epilepsy. Neurosurgery. 2014; 74(6):569-585.
62. Wu C, Jermakowicz WJ, Chakravorti S, et al. Effects of surgical targeting in laser interstitial thermal therapy for mesial temporal lobe epilepsy: a multicenter study of 234 patients. Epilepsia. 2019; 60(6):1171-1183.
63. Wu Z, Zhao Q, Tian Z, et al. Efficacy and safety of a new robot-assisted stereotactic system for radiofrequency thermocoagulation in patients with temporal lobe epilepsy. Exp Ther Med. 2014; 7(6):1728- 1732.
64. Xue F, Chen T, Sun H. Postoperative outcomes of magnetic resonance imaging (MRI)-guided laser interstitial thermal therapy (LITT) in the treatment of drug-resistant epilepsy: a meta-analysis. Med Sci Monit. 2018; 24:9292-9299.
65. Youngerman BE, Oh JY, Anbarasan D, et al; Columbia Comprehensive Epilepsy Center Co-Authors. Laser ablation is effective for temporal lobe epilepsy with and without mesial temporal sclerosis if hippocampal seizure onsets are localized by stereoelectroencephalography. Epilepsia. 2018; 59(3):595-606.
66. Youngerman BE, Save AV, McKhann GM. Magnetic resonance imaging-guided laser interstitial thermal therapy for epilepsy: systematic review of technique, indications, and outcomes. Neurosurgery. 2020; 86(4):E366-E382.

Government Agency, Medical Society, and Other Authoritative Publications:

1. Centers for Disease Control and Prevention (CDC). Epilepsy Facts and Stats. Updated May 15, 2024. Available at: https://www.cdc.gov/epilepsy/data-research/facts-stats/. Accessed on October 12, 2025.
2. Fisher RS, Acevedo C, Arzimanoglou A, et al. ILAE official report: a practical clinical definition of epilepsy. Epilepsia. 2014; 55(4):475-82.
3. Kwan P, Arzimanoglou A, Berg AT, et al. Definition of drug resistant epilepsy: consensus proposal by the ad hoc Task Force of the ILAE Commission on Therapeutic Strategies. Epilepsia. 2010; 51(6):1069-1077.
4. Laser Interstitial Thermal Therapy for Treating Intracranial Lesions and Epilepsy. A Health Technology Assessment and Policy Analysis. January 27, 2016. Available at: https://obrieniph.ucalgary.ca/sites/default/files/Nav%20Bar/Groups/HTA/litt-jan-27th-2016-references-fixed.pdf. Accessed on October 12, 2025.
5. U.S. Food & Drug Administration:
   • NeuroBlate^® System (Monteris Medical; Plymouth, MN). 510(K) Number: K173305. November 17, 2017. Available at: https://www.accessdata.fda.gov/cdrh_docs/pdf17/K173305.pdf. Accessed on October12, 2025.
   • Tranberg® Thermoguide Therapy System (Clinical Laserthermia Systems, Lund, Sweden). 510(K) Number: K214125. September 22, 2022. Available at: https://www.accessdata.fda.gov/cdrh_docs/pdf21/K214125.pdf. Accessed on October 12, 2025.
   • Visualase^® Thermal Therapy System (Medtronic; Minneapolis, MN). 510(K) Number: K053087. March 1, 2006. Available at: https://www.accessdata.fda.gov/cdrh_docs/pdf5/K053087.pdf. Accessed on October 12, 2025.
6. Wu C, Schwalb JM, Rosenow JM et al. The American Society for Stereotactic and Functional Neurosurgery position statement on laser interstitial thermal therapy for the treatment of drug-resistant epilepsy. Neurosurgery. 2022; 90:155-160.

1. National Institute of Health. National Institute of Neurological Disorders and Stroke. Epilepsy and Seizures. Last reviewed Last reviewed on April 07, 2025. Available at: https://www.ninds.nih.gov/disorders/all-disorders/epilepsy-information-page. Accessed on October 10, 2025.
2. National Organization for Rare Disorders (NORD). Hypothalamic Hamartoma. Last updated August 16, 2017. Available at: https://rarediseases.org/rare-diseases/hypothalamic-hamartoma/. Accessed on October 10, 2025.
3. The Epilepsy Foundation. LITT Thermal Ablation. Available at: https://www.epilepsy.com/treatment/surgery/types/litt-thermal-ablation. Accessed on October 10, 2025.
4. The Epilepsy Foundation. Understanding Epilepsy. What is Epilepsy? Available at: https://www.epilepsy.com/what-is-epilepsy. Accessed on October 10, 2025.

NeuroBlate System
Tranberg Thermoguide Therapy System
Visualase MRI-Guided Laser Ablation System

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