Accounting for repeat intervention costs in the economic comparison of laser interstitial thermal therapy and anterior temporal lobectomy for treatment of refractory temporal lobe epilepsy.

OBJECTIVE: Laser interstitial thermal therapy (LITT) is an alternative to anterior temporal lobectomy (ATL) for the treatment of temporal lobe epilepsy that has been found by some to have a lower procedure cost but is generally regarded as less effective and sometimes results in a subsequent procedure. The goal of this study is to incorporate subsequent procedures into the cost and outcome comparison between ATL and LITT. METHODS: This single-center, retrospective cohort study includes 85 patients undergoing ATL or LITT for temporal lobe epilepsy during the period September 2015 to December 2022. Of the 40 patients undergoing LITT, 35 % (N = 14) underwent a subsequent ATL. An economic cost model is derived, and difference in means tests are used to compare the costs, outcomes, and other hospitalization measures. RESULTS: Our model predicts that whenever the percentage of LITT patients undergoing subsequent ATL (35% in our sample) exceeds the percentage by which the LITT procedure alone is less costly than ATL (7.2% using total patient charges), LITT will have higher average patient cost than ATL, and this is indeed the case in our sample. After accounting for subsequent surgeries, the average patient charge in the LITT sample ($103,700) was significantly higher than for the ATL sample ($88,548). A second statistical comparison derived from our model adjusts for the difference in effectiveness by calculating the cost per seizure-free patient outcome, which is $108,226 for ATL, $304,052 for LITT only, and $196,484 for LITT after accounting for the subsequent ATL surgeries. SIGNIFICANCE: After accounting for the costs of subsequent procedures, we found in our cohort that LITT is not only less effective but also results in higher average costs per patient than ATL as a first course of treatment. While cost and effectiveness rates will vary across centers, we also provide a model for calculating cost effectiveness based on individual center data.

Long-term epilepsy surgery outcomes in patients with PET-positive, MRI-negative temporal lobe epilepsy.

This study compared the long-term efficacy of anterior temporal lobectomy (ATL) for the treatment of medically refractory temporal lobe epilepsy (TLE) in patients who presented with ipsilateral temporal PET hypometabolism and nonlesional magnetic resonance imaging (PET+/MRI-) with that in patients who had mesial temporal sclerosis (MTS) on MRI. We described the electroclinical, MRI, PET, and pathological characteristics and seizure outcome of 28 PET+/MRI--patients without discordant ictal and interictal electroencephalography (EEG) who underwent ATL (2004-2007) for medically refractory partial epilepsy while avoiding intracranial monitoring. The primary outcome was the percentages of Engel Class I outcomes at 2 and 5 years of PET+/MRI--patients compared with those of patients with MTS on MRI; neuropsychological testing was used as the secondary outcome. At 2-year follow-up, 21 (75%) patients in the PET+/MRI--group were in Engel Class I compared with 66 (75.9%) patients with MTS, and at 5-year follow-up, 20 (71.4%) patients in the PET+/MRI--group were in Engel Class I compared with 64 (73.6%) patients in the group with MTS. There were no significant differences between the groups at either time period. We concluded that normal MRI results should not preclude presurgical evaluations in patients with medically refractory TLE, as favorable long-term postoperative seizure outcomes are possible, especially in patients with unilateral anterior interictal epileptiform discharges and ipsilateral temporal PET hypometabolism.

Positron Emission Tomography (PET) in presurgical planning of anterior temporal lobectomy: A systematic review of efficacy and limitations.

INTRODUCTION: Temporal lobe epilepsy (TLE), a debilitating neurological disorder, necessitates refined diagnostic and treatment strategies. This comprehensive review appraises the potential of positron emission tomography (PET) in enhancing the presurgical planning of Anterior Temporal Lobectomy (ATL) for patients afflicted with TLE. METHODS: A comprehensive literature search was conducted using the PubMed, SCOPUS, and ScienceDirect databases from 1985 to 2022, following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for studies investigating PET and ATL. This review studied a range of radiotracers, including FDG, H2O, FMZ, MPPF, and FCWAY, analyzing their efficacy in detecting epileptogenic foci, establishing resection boundaries, and predicting postoperative outcomes. The study paid special attention to cases where MRI findings were inconclusive. RESULTS: A total of 52 studies were included in the final analysis. Our analysis revealed that FDG-PET imaging was instrumental in identifying seizure foci and predicting postoperative results. It exhibited significant value in situations where structural abnormalities were absent on MRI scans. Furthermore, newer radiotracers such as 5-HT1A antagonists, FCWAY and MPPF, presented promising potential for localizing seizure foci, particularly in MRI-negative TLE, despite their comparatively limited current usage. CONCLUSION: PET imaging, although challenged by issues such as radiation exposure, limited accessibility, and high costs, offers considerable promise. Integration with other imaging modalities, such as EEG and MRI, has contributed to improved localization of epileptogenic foci and subsequently, enhanced surgical outcomes. Further research must focus on establishing the relative efficacy and optimal combinations of these radiotracers in the orchestration of ATL surgical planning and prognostication of postoperative outcomes for TLE patients. Encouragingly, these advancements hold the potential to revolutionize the management of TLE, delivering a better quality of life for patients.

Combined Depth and Subdural Electrodes for Lateralization of the Ictal Onset Zone in Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis.

(1) Objective: This study aimed to explore the efficacy of conventional invasive techniques in confirming unilateral seizure onset localization in mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) and to investigate the association between electrode type and intracranial electroencephalography (EEG) pattern. (2) Methods: This retrospective study encompasses patients diagnosed with MTLE-HS who underwent an invasive study prior to an anterior temporal lobectomy (ATL). Intracranial EEG features were assessed for 99 seizure events from 25 selected patients who achieved seizure remission with ATL after an invasive study using bilateral combined depth and subdural electrodes. Their findings were compared to those of 21 seizure events in eight patients who exhibited suboptimal seizure outcomes. (3) Results: For the distribution of electrodes that recorded the ictal onset, hippocampal depth electrodes recorded 96% of all seizure events, while subdural electrodes recorded 52%. Among the seizures recorded in subdural electrodes, 49% were localized in medial electrodes, with only 8% occurring in lateral electrodes. The initiation of seizures exclusively detected in hippocampal depth electrodes was associated with successful seizure remission, whereas those solely recorded in the lateral strip electrodes were often linked to refractory seizures after ATL. (4) Conclusions: These findings emphasize the importance of employing a combination of depth and subdural electrodes in invasive studies for patients with MTLE-HS to enhance the accuracy of lateralization. This also cautions against sole reliance on subdural electrodes without depth electrodes, which could lead to inaccurate localization.

A Comparison of Neuropsychological Outcomes following Responsive Neurostimulation and Anterior Temporal Lobectomy in Drug-Resistant Epilepsy.

Neuropsychological outcomes following temporal lobe resection for drug-resistant epilepsy (DRE) are well established. For instance, left anterior temporal lobectomy (LATL) is associated with a greater risk for cognitive morbidity compared to right (RATL). However, the impact of neuromodulatory devices, specifically responsive neurostimulation (RNS), remains an area of active interest. There are currently no head-to-head comparisons of neuropsychological outcomes after surgical resection and neuromodulation. This study reports on a cohort of 21 DRE patients with the RNS System who received comprehensive pre- and post-implantation neuropsychological testing. We compared both cognitive and seizure outcomes in the RNS group to those of 307 DRE patients who underwent LATL (n = 138) or RATL (n = 169). RNS patients had higher seizure rates pre-intervention. While fewer in the RNS group achieved Class I Engel outcomes compared to the ATL cohorts, RNS patients also showed seizure frequency declines from pre- to post-intervention that were similar to those who underwent resective surgery. Moreover, the RNS and RATL groups were similar in their neuropsychological outcomes, showing no significant cognitive decline post-intervention. In contrast, the LATL group notably declined in object naming and verbal list learning. Direct comparisons like this study may be used to guide clinicians in shared decision making to tailor management plans for patients' overall treatment goals.

Intracranial electrodes monitoring improves seizure control and complication outcomes for patients with temporal lobe epilepsy - A retrospective cohort study.

BACKGROUND: Anterior temporal lobectomy (ATL) is the standard surgical treatment for temporal lobe epilepsy (TLE), but patients may suffer from recurrent seizures post-surgery. Invasive electrical monitoring plays a critical role in precisely identifying the epileptic foci. This study aimed to evaluate and compare the benefits of long-term invasive electroencephalography (EEG) monitoring and two-stage surgery with the classical approach to examine their effect on post-surgical brain function and complications. MATERIALS AND METHODS: Patients with TLE (N = 198) who underwent epilepsy surgery were retrospectively evaluated. Diagnosis of TLE was confirmed based on clinical grounds (semiology), EEG findings, and magnetic resonance imaging (MRI). Long-term invasive video EEG was performed; epileptiform discharges were recorded. Patients underwent either classical ATL or modified two-step surgery with electrodes implantation. Histopathological examination was performed. The patients were followed up at 1, 3, and 5 years after surgery. RESULTS: Twenty-three and 175 patients underwent classical ATL and two-stage surgery, respectively. On histopathological examination, inflammation, hippocampal sclerosis, and cortical dysplasia were found to be the leading pathological causes of epileptic foci in both groups. MRI results were not consistent with the pathological findings. Grade II and III Engel scores were more frequent in the ATL group compared to two-stage surgery during follow-up. No postoperative complications were reported in two-stage surgery during follow-up, but one patient had mild hemiplegia in the ATL group. CONCLUSIONS: Preoperative invasive monitoring with long-term EEG helps locate the epileptic foci precisely. Postsurgical complications are rare compared to classical ATL, with better prognosis and seizure freedom after surgery.

Surgical outcomes in patients with intraoperative Electrocorticography (EcoG) guided epilepsy surgery-experiences of a tertiary care centre in India.

INTRODUCTION: The Comprehensive Epilepsy Surgery Program was started in 2001 at K.E.M. Hospital, Mumbai with the aim of performing epilepsy surgeries at highly concessional rates. We have started using intraoperative Electrocorticography (EcoG) since 2009 in patients with tumors, Mesial Temporal Sclerosis (MTS) plus and focal cortical dysplasia (FCD). This study highlights our experience with EcoG and it's utility in epilepsy surgery.introduction METHODS: 51 patients with drug resistant epilepsy due to temporal and extra-temporal tumors, MTS plus and FCD underwent pre-surgical evaluation and ECoG guided epilepsy surgery through our program. The surgical procedures employed included intraoperative EcoG guided lesionectomy or a lesionectomy with Anterior Temporal Lobectomy (ATL). Postoperative MRI and EEG were done. Seizure freedom was categorized as per Engel's classification. RESULTS: At a mean follow up of 33 months (range: 14-69 months), 43 out of 51(84.31%) patients were completely seizure free post-surgery (Engel's Class I). Among the patients who were not seizure free, 3 patients were in Engel's Class II and 5 patients were in Engel's Class III. Presence of a residual lesion on postoperative MRI (p < 0.001), abnormal postoperative EEG (p < 0.001) and persistent spikes on post-resection EcoG (p < 0.05) had a significant statistical association with poor seizure freedom post-surgery. CONCLUSION: The success of epilepsy surgery depends upon accurate localization and complete resection of the epileptogenic tissue, both of which are aided by intraoperative EcoG.Thus, intraoperative EcoG is a useful adjunct in epilepsy surgery to achieve optimal seizure freedom in cases of MTS plus, focal cortical dysplasia and tumors. Even the patients who are not seizure free can achieve worthwhile improvement post surgery.

Clinical characteristics, surgical and neuropsychological outcomes in drug resistant tumoral temporal lobe epilepsy.

INTRODUCTION: Glioneuronal tumors are found in nearly one third patients who undergo surgery for pharmacoresistant epilepsy with temporal lobe being the most common location. Few studies, however have concentrated on the neurological and neuropsychological outcomes after surgery, hitherto none from India. METHODS: We studied 34 patients with temporal lobe tumors and drug resistant epilepsy. These patients underwent anterior temporal lobectomy or lesionectomy based on the involvement of the hippocampus and mesial temporal structures. The clinical history, EEG, neuropsychology profile and MRI were compared. Seizure outcome was categorized using Engel's classification. RESULTS: At a mean follow up of 62 months, 85.29% of the patients were seizure free (Engel's Class I). All 8 patients with intraoperative electrocorticography (ECoG) guided resection were seizure free. DISCUSSION: Presence of a residual lesion was significantly associated with persistence of seizures post surgery (p = 0.002). Group analysis revealed no significant shifts in IQ and memory scores postoperatively. There was a significant improvement in the quality of life scores (total and across all subdomains) in all patients (p < 0.001). Postoperative EEG abnormalities predicted unfavorable ​seizure outcome. CONCLUSION: Surgery for temporal lobe tumors and refractory epilepsy offers complete seizure freedom in majority. Complete surgical excision of the epileptogenic zone is of paramount importance in achieving seizure freedom. Intraoperative electrocorticography (EcoG) is a useful adjunct to ensure complete removal of epileptogenic zone, thus achieving optimal seizure freedom. There is a significant improvement in the quality of life scores (p < 0.001) with no negative impact of surgery on memory and intelligence. Even the patients who are not seizure free can achieve worthwhile improvement post surgery.