Postoperative Neurologic Outcome in Patients Undergoing Resective Surgery for Parietal Lobe Epilepsy: A Systematic Review.

BACKGROUND AND OBJECTIVES: Parietal lobe epilepsy (PLE) surgery can be an effective treatment for selected patients with intractable epilepsy but can be associated with the risk of serious neurologic deficits. We performed a systematic review of the literature to obtain a comprehensive summary of the frequency and types of new postoperative neurologic deficits in patients undergoing PLE resective surgery. METHODS: We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials for articles published between January 1, 1990, and April 28, 2022. We included studies that reported postoperative neurologic outcome following PLE resective surgery confined to the parietal lobe. We required that studies included ≥5 patients. The data collected included demographic information and specific details of postoperative neurologic deficits. When available, individual patient data were collected. We used the Risk of Bias in Nonrandomized Studies of Interventions tool to assess the risk of bias and Grading of Recommendations Assessment, Development, and Evaluation to assess the quality of the evidence. RESULTS: Of the 3,461 articles screened, 33 studies met the inclusion criteria. A total of 370 patients were included. One hundred patients (27.0%) had a new deficit noted postoperatively. Approximately half of the patients with deficits experienced only transient deficits. Motor deficits were the most commonly identified deficit. The rates of motor deficits noted after PLE surgery were 5.7%, 3.2%, and 2.2% for transient, long-term, and duration not specified, respectively. Sensory and visual field deficits were also commonly reported. Gerstmann syndrome was noted postoperatively in 4.9% of patients and was almost always transient. Individual patient data added information on parietal lobe subregion postoperative neurologic outcome. DISCUSSION: Our systematic review provides a comprehensive summary of the frequency and types of neurologic deficits associated with PLE surgery. A significant percentage of postoperative deficits are transient. In addition to the expected sensory and visual deficits, PLE surgery is associated with a notable risk of motor deficits. The available literature has important deficiencies. Our study highlights gaps in the literature and provides recommendations for future directions. TRIAL REGISTRATION INFORMATION: This systematic review was registered on PROSPERO (CRD42022313108, May 26, 2022).

Temporo-Parieto-Occipital Disconnection by Robot-Assisted Magnetic Resonance Imaging-Guided Laser Interstitial Thermal Therapy for Refractory Epilepsy in a Pediatric Patient: Proof-of-Principle Case Report and Surgical Nuances.

OBJECTIVE: Magnetic resonance imaging-guided laser interstitial thermal therapy (MRIgLITT) has been proven safe and effective for the treatment of focal epilepsy of different etiologies. It has also been used to disconnect brain tissue in more extensive or diffuse epilepsy, such as corpus callosotomy and hemispherotomy. METHODS: In this study, we report a case of temporo-parieto-occipital disconnection surgery performed using MRIgLITT assisted by a robotic arm for refractory epilepsy of the posterior quadrant. A highly realistic cadaver simulation was performed before the actual surgery. RESULTS: The patient was a 14-year-old boy whose seizures began at the age of 8. The epilepsy was a result of a left perinatal ischemic event that caused a porencephalic cyst, and despite receiving multiple antiepileptic drugs, the patient continued to experience daily seizures which led to the recommendation of surgery. CONCLUSIONS: A Wada test lateralized language in the right hemisphere. Motor and sensory function was confirmed in the left hemisphere through magnetic resonance imaging functional studies and NexStim. The left MRIgLITT temporo-parieto-occipital disconnection disconnection was achieved using 5 laser fibers. The patient followed an excellent postoperative course and was seizure-free, with no additional neurological deficits 24 months after the surgery.

Spontaneous unilateral spatial neglect recovery after brain tumour resection: A multimodal diffusion and rs-fMRI case report.

Patients with unilateral spatial neglect (USN) are unable to explore or to report stimuli presented in the left personal and extra-personal space. USN is usually caused by lesion of the right parietal lobe: nowadays, it is also clear the key role of structural connections (the second and the third branch of the right Superior Longitudinal Fasciculus, respectively, SLF II and III) and functional networks (Dorsal and Ventral Attention Network, respectively, DAN and VAN) in USN. In this multimodal case report, we have merged those structural and functional information derived from a patient with a right parietal lobe tumour and USN before surgery. Functional, structural and neuropsychological data were also collected 6 months after surgery, when the USN was spontaneously recovered. Diffusion metrics and Functional Connectivity (FC) of the right SLF and DAN, before and after surgery, were compared with the same data of a patient with a tumour in a similar location, but without USN, and with a control sample. Results indicate an impairment in the right SLF III and a reduction of FC of the right DAN in patients with USN before surgery compared to controls; after surgery, when USN was recovered, patient's diffusion metrics and FC showed no differences compared to the controls. This single case and its multimodal approach reinforce the crucial role of the right SLF III and DAN in the development and recovery of egocentric and allocentric extra-personal USN, highlighting the need to preserve these structural and functional areas during brain surgery.

Preserving the ability to discriminate between left and right; A case study.

Left-right orientation, a function related to the parietal lobe, is important for many daily activities. Here, we describe a left-handed patient with a right parietal brain tumour. During awake surgery, electric stimulation of the right inferior parietal lobe resulted in mistakes in his left-right orientation. Postoperatively our patient had no problems in discriminating left right. This case report shows that monitoring of left-right orientation during awake brain tumour surgery is feasible so that this function can be preserved.

How we do it? The surgical resection of a medial parietal arteriovenous malformation under multimodal imaging technology-guided hybrid operation.

BACKGROUND: This report described the surgical resection of a challenging medial parietal lobe arteriovenous malformation (AVM) using the hybrid operation theater with a multimodal imaging-guided technology. METHOD: A 29-year-old male was admitted to treat a ruptured medial parietal AVM. The deep and diffusive compartment of the nidus was embolized before resection. Preoperatively and intraoperatively, mixed reality technology with multimodality imaging was utilized for surgical planning and navigation. The nidus was totally resected and confirmed by intraoperative angiography. The patient recovered without sequella. CONCLUSION: We hope this report provides new insights into applying multimodal imaging technology-guided hybrid operation for brain AVM.

Atrium meningioma: Transtubular posterior intraparietal sulcus approach.

Meningiomas that arise in the atria of the lateral ventricles are relatively rare lesions, that pose a unique challenge for surgery due to their deep-seated location and proximity to critical white matter tracts. Size and anatomical variations can affect the best approach for these tumors, with several approaches described to access the atrium including the interhemispheric trans-precuneus, trans-supramarginal gyrus, distal trans-sylvian, supracerebellar trans-collateral sulcus, and finally the trans-intraparietal sulcus approach, which was the choice for this case. Minimally invasive techniques that preserve the surrounding tissue are becoming increasingly popular and are perfectly suited to deep seated lesions. The relevant subcortical anatomy surrounding the atrium is discussed. The optic radiations form the lateral wall of the atrium, whereas commissural fibers of the tapetum form the roof of the atrium, and superficial to these fibers we have the superior longitudinal fasciculus that have vertical rami that communicate with the superior parietal lobule. Utilizing the posterior half of the intraparietal sulcus can preserve these fibers. The use of neuronavigation, brain magnetic resonance imaging with diffusion tensor imaging (DTI) tractography may be helpful in the surgical planning. In this article, we present a surgical video of a trans-tubular interparietal sulcus approach for resection of an atrium meningioma. A 43-year-old right-handed female who presented with progressive headaches and a diagnosis of idiopathic intracranial hypertension was found to have an atrial meningioma that grew in follow-up and surgery was recommended. We chose the posterior intraparietal sulcus approach as it provides a good angle of attack while preserving the optic radiations and most of the superior longitudinal fasciculus, using a tubular retractor to minimize tissue damage. Gross total resection of the tumor was achieved with complete preservation of patient neurological function.

Interhemispheric Transcingulate Sulcus Approach to Deep-Seated Medial Frontal and Parietal Lesions-Fiber Dissection Study With Illustrative Cases.

BACKGROUND: Surgery for lesions located in the medial frontal and parietal lobes can be quite challenging for neurosurgeons because of morbidities that may arise from damage to critical midline structures or intact neural tissue that need to be crossed to reach the lesion. In our anatomic studies, the cingulate sulcus was observed as an alternative access route for lesions located in medial frontal and parietal lobes. OBJECTIVE: To explain the microsurgical anatomy of the medial hemisphere and cingulate sulcus and to demonstrate the interhemispheric transcingulate sulcus approach (ITCSA) with 3 clinical cases. METHODS: Five formalin-fixed brain specimens, which were frozen at -18 °C for at least 2 weeks and then thawed under tap water, were gradually dissected from medial to lateral. Diffusion fiber tracking performed using DSI Studio software in data was provided by the Human Connectome Project. Clinical data of 3 patients who underwent ITCSA were reviewed. RESULTS: Cingulate sulcus is an effortlessly identifiable continuous sulcus on the medial surface of the brain. Our anatomic dissection study revealed that the lesions located in the deep medial frontal and parietal lobes can be reached through the cingulate sulcus with minor injury only to the cingulum and callosal fibers. Three patients were treated with ITCSA without any neurological morbidity. CONCLUSION: Deep-seated lesions in the medial frontal lobe and parietal lobe medial to the corona radiata can be approached by using microsurgical techniques based on anatomic information. ITCSA offers an alternative route to these lesions besides the known lateral transcortical/transsulcal and interhemispheric transcingulate gyrus approaches.

Evidence for a critical role of the left inferior parietal lobule and underlying white matter connectivity in proficient text reading.

OBJECTIVE: Reading proficiency is an important skill for personal and socio-professional daily life. Neurocognitive models underlie a dual-route organization for word reading, in which information is processed by both a dorsal phonological "assembled phonology route" and a ventral lexical-semantic "addressed phonology route." Because proficient reading should not be reduced to the ability to read words one after another, the current study was designed to shed light on the neural bases specifically underpinning text reading and the relative contributions of each route to this skill. METHODS: Twenty-two patients with left-sided, diffuse, low-grade glioma who underwent operations while awake were included. They were divided into 3 groups on the basis of tumor location: the inferior parietal lobule (IPL) group (n = 6), inferior temporal gyrus (Tinf) group (n = 6), and fronto-insular (control) group (n = 10). Spoken language and reading abilities were tested in all patients the day before surgery, during surgery, and 3 months after surgery, and cognitive functioning was evaluated before and 3 months after surgery. Text-reading scores obtained before and 3 months after surgery were compared within each group and between groups, correlations between reading scores and both spoken language and cognitive scores were calculated, postoperative cortical-subcortical resection location was estimated, and multiple regression analysis was conducted to examine the relationship between reading proficiency and lesion location. RESULTS: The results indicated that only the patients in the IPL group showed a significant decrease in text-reading scores between periods, which was not associated with lower scores in naming or verbal fluency; patients in the Tinf group showed a slight nonsignificant decrease in text reading between periods, which was associated with a clear decrease in naming and semantic verbal fluency; and patients in the control group showed no differences between preoperative and postoperative reading and spoken language scores. The results of the analysis of these behavioral results and anatomical data (resection cavities and white matter damage) suggest critical roles for the left inferior parietal lobule and underlying white matter connectivity, especially the posterior segment of the arcuate fasciculus, in proficient text reading. CONCLUSIONS: Text-reading proficiency may depend on not only the integrity of both processing routes but also their capacity for interaction, with critical roles for the left inferior parietal lobule and posterior arcuate fasciculus. These findings have fundamental as well as clinical implications.

The effects of cognitive, physical, and somatosensory rehabilitation after right temporo-parietal tumor resection on cognitive, motor, somatosensory, and electrophysiological parameters: A case report.

INTRODUCTION: This report examines the effects of a multimodal rehabilitation program which includes cognitive, physical, and somatosensory rehabilitation after right temporo-parietal tumor resection on cognitive, motor, somatosensory, and electrophysiological parameters. CASE DESCRIPTION: A 22-year-old patient presented with sensory loss in the dominant left hand and reduced writing ability after right temporo-parietal lobe resection. Cognitive, motor, and sensory evaluations were carried out pre and post-treatment. The patient's spontaneous electroencephalo-gram (EEG) and an EEG during application of transcutaneous electrical nerve stimulation (TENS) (TENS EEG) were recorded. As a reference for the patient's electrophysiological values, EEGs of 4 healthy individuals were also taken. Over a period of 1 year, the patient received multimodal rehabilitation which includes cognitive, physical, and somato-sensory rehabilitation on 2 days each week. OUTCOMES: An improvement of the patient's cognitive capacities, motor strength, superficial, deep and cortical sensations was achieved. After rehabilitation, an increase in parietal and occipital alpha activity as well as in frontal and parietal beta activity was seen both in spontaneous EEG and in TENS EEG. With increasing TENS intensity, alpha and beta power increased as well. CONCLUSION: Our findings suggest that a multimodal rehabilitation program may improve cognitive, sensory, and motor effects after resection due to tumor surgery.

The ventral precuneal-posterior cingulate region as a site of epileptogenicity

The ventral precuneal and posterior cingulate area (VP-PC) represents a distinct but topographically variable mesial parietal site of epileptogenicity that may manifest as a common temporal lobe-mediated ictal expression. In a review of records of 62 presumptive epilepsy surgery cases, two cases of primary epileptogenicity expressed within the VP-PC were identified and are detailed to bring attention to this electroencephalographically-hidden area of ictal expression. Details of their investigation and surgical treatment illustrate distinctly different approaches addressing the problem and bringing about a seizure-free outcome.

A Retrospective Study of Parietal Lobe Epilepsy: Functional Anatomy and Surgical Treatment.

Context: Parietal lobe epilepsy (PLE) accounts for approximately 5% of all focal epilepsies worldwide,1 and few PLE patients have undergone epilepsy surgery in the past. With the introduction of functional neuroimaging methods, such as interictal fluorodeoxyglucose-positron emission tomography (FDG-PET), stereotactic electroencephalograms (SEEGs), and high-resolution magnetic resonance imaging (MRI), more patients with intractable neocortical epilepsy have been considered for surgical treatment. Objective: The study intended to characterize the clinical features, aura, and presurgical evaluations of patients with PLE, by investigating their demographic and clinical characteristics, and to evaluate the prognostic value of the four diagnostic modalities-MRI, FDG-PET, scalp EEG, and SEEG-in terms of the localization of epileptogenic area. Design: The research team performed a retrospective analysis of outcomes for PLE patients who underwent resistive brain surgery. Setting: The study took place in the Neurosurgery Department of Epilepsy at the Second Hospital of Hebei Medical University in Shijiazhuang, China. Participants: Participants were 9 PLE patients, 4 males and 5 females, who underwent epilepsy surgery at the hospital between 2017 and 2019. Outcome Measures: The measures included demographic data, seizure data, electroencephalogram (EEG) recordings, magnetic resonance imaging (MRI) of the brain, positron emission tomography (PET), and stereotactic electroencephalogram (SEEG). The pathological findings were reviewed. Results: The five participants who had a PET all had positive results. Eight participants who had parietal lobe lesions had an MRI, and four had a stereotactic electroencephalogram (SEEG) that localized the epileptogenic zone. The interictal scalp EEG recordings for seven participants showed an abnormality, and six participants who had ictal surface EEG recordings showed parietal ictal EEG onset. Conclusions: Surgical excision of epileptogenic foci is the main treatment for drug-resistant PLE. Parietal functional anatomy is the basis for understanding and diagnosing PLE. Aura, semiology, interictal EEG, and PET are an important foundation for evaluation of PLE patients, and the SEEG is the most valuable tool, allowing localization of the epileptogenic zone.

On the cutting edge of glioblastoma surgery: where neurosurgeons agree and disagree on surgical decisions.

OBJECTIVE: The aim of glioblastoma surgery is to maximize the extent of resection while preserving functional integrity. Standards are lacking for surgical decision-making, and previous studies indicate treatment variations. These shortcomings reflect the need to evaluate larger populations from different care teams. In this study, the authors used probability maps to quantify and compare surgical decision-making throughout the brain by 12 neurosurgical teams for patients with glioblastoma. METHODS: The study included all adult patients who underwent first-time glioblastoma surgery in 2012-2013 and were treated by 1 of the 12 participating neurosurgical teams. Voxel-wise probability maps of tumor location, biopsy, and resection were constructed for each team to identify and compare patient treatment variations. Brain regions with different biopsy and resection results between teams were identified and analyzed for patient functional outcome and survival. RESULTS: The study cohort consisted of 1087 patients, of whom 363 underwent a biopsy and 724 a resection. Biopsy and resection decisions were generally comparable between teams, providing benchmarks for probability maps of resections and biopsies for glioblastoma. Differences in biopsy rates were identified for the right superior frontal gyrus and indicated variation in biopsy decisions. Differences in resection rates were identified for the left superior parietal lobule, indicating variations in resection decisions. CONCLUSIONS: Probability maps of glioblastoma surgery enabled capture of clinical practice decisions and indicated that teams generally agreed on which region to biopsy or to resect. However, treatment variations reflecting clinical dilemmas were observed and pinpointed by using the probability maps, which could therefore be useful for quality-of-care discussions between surgical teams for patients with glioblastoma.

Avoidance and Improvement in Visual Field Defect After Surgery for Metastatic Brain Tumors in the Parietal and the Occipital Lobe.

OBJECTIVE: Visual field defects occasionally occur secondary to tumors in the parietal and the occipital lobes. The aim of this study was to analyze the efficacy of improvement in hemianopsia after surgery for metastatic brain tumors involving or adjacent to the optic radiation (OR). METHODS: The study included 49 patients with brain metastasis in the parietal and occipital lobes in the present study. Preoperative and postoperative neurological assessments included visual field, Mini-Mental State Examination, and Karnofsky performance scale. RESULTS: Of 49 patients, 33 (67.3%) presented with preoperative homonymous hemianopsia. Of these 33 patients, the visual field was improved postoperatively in 17 patients (51.5%). In all patients regardless of preoperative hemianopsia, postoperative visual fields did not deteriorate. Tractography demonstrated that the OR was split by the tumor (n = 6) and fanning of fibers expanded along the lateral side of the tumor (n = 11). All tumors were removed via surgical access toward the medial side of the tumor. Gross total resection was achieved in most tumors in the group with visual improvement (n = 16/17; 94.1%). Improvement in the visual field was attributed to tumor location in the subcortical white matter, removal rate of the tumor, and higher postoperative Karnofsky performance scale score. CONCLUSIONS: The OR tended to deviate to the lateral side of the tumor in the parieto-occipital junction. The postoperative visual field improved even in cases of an occipital tumor. Based on the present study, total resection via an appropriate surgical route should be considered to preserve the OR, leading to improvement in the postoperative visual field.

Posterior Transposition of the Frontal Bridging Veins Together with Sphenoparietal Sinus: A Simple Technique to Widen the Surgical Corridor During Pterional Clipping of the Anterior Communicating Artery.

BACKGROUND: High-positioned and/or superoposteriorly directed anterior communicating artery aneurysms can be treated by direct clipping using the pterional (fronto-temporo-sphenoidal) approach. This procedure, however, requires stronger retraction of the frontal lobe. Hence, preservation of the prominent frontal bridging veins (FBVs) draining into the sphenoparietal sinus (SPS) remains a significant challenge in preventing postoperative venous congestion. METHODS: We developed a technique to release the tension on the FBVs by pulling them together with the SPS epidurally. In 2 patients, who had presented with high-positioned and/or superoposteriorly directed anterior communicating artery aneurysms, we peeled off the arachnoid surrounding the FBVs and detached it from the brain surface. We further released the veins by moving them posteriorly, together with the SPS epidurally. RESULTS: Using this technique, we established a wide corridor through a more lateral transsylvian trajectory with effective posterior retraction of the frontal lobe and were successful in clipping and obliterating the aneurysms. CONCLUSIONS: Open clipping of unruptured intracranial aneurysms requires accuracy to preserve higher brain function. Our technique was successful in both patients, and preserving the FBVs could be useful in the treatment of such aneurysms.

Intracerebral schwannoma of the angular gyrus: case report.

We report an intracerebral schwannoma originating in the angular gyrus of a 20-year-old female that was incidentally diagnosed after she presented with a post-traumatic seizure. After comprehensive investigations, including functional magnetic resonance imaging, she underwent a computed tomography-guided stereotactic resection of the lesion. Pathological examination confirmed features of a schwannoma. After six years of follow-up, she remains well, without any evidence of recurrence. Intracerebral schwannomas are extremely uncommon: fewer than 90 cases have been reported. We present a comprehensive summary of the literature and a discussion of novel theories on the pathogenesis of intracerebral schwannomas.

Non-fatal Bihemispheric Penetrating Brain Injury from a Crossbow Arrow with Good Clinical Outcome: Case Report

Crossbow injuries to the head have seldom been reported in the literature, and they represent a unique type of penetrating brain injury (PBI) in which a low-velocity arrow results in an intracranial fragment larger than most high-velocity projectiles, usually with a lethal outcome.We present the case of a 34-year-oldman who attempted suicide with a self-inflicted cranial injury from a crossbow arrow, with a right parietal point of entry and a palpable subcutaneous tip in the left parietal region. The emergency team reported a Glasgow coma scale (GCS) score of 15, and the patient was brought sedated and intubated. Computed tomography (CT) imaging scans showed that the arrow crossed both parietal lobes, with mild subarachnoid hemorrhage and small cerebral contusions adjacent to its intracranial path. Careful retrograde removal of the penetrating arrow was performed in the CT suite, followed by an immediate CT scan, which excluded procedure-related complications. The patient woke up easily and was discharged 3 days later withmild left hand apraxia and no other neurologic deficits. To the best of our knowledge, there are no similar case reports describing both good clinical outcome and rapid discharge after a bihemispheric PBI. Individualizing the management of each patient is therefore crucial to achieve the best possible outcome as PBI cases still represent a major challenge to practicing neurosurgeons worldwide.

Detrended fluctuation analysis in the presurgical evaluation of parietal lobe epilepsy patients.

OBJECTIVE: To examine the usability of long-range temporal correlations (LRTCs) in non-invasive localization of the epileptogenic zone (EZ) in refractory parietal lobe epilepsy (RPLE) patients. METHODS: We analyzed 10 RPLE patients who had presurgical MEG and underwent epilepsy surgery. We quantified LRTCs with detrended fluctuation analysis (DFA) at four frequency bands for 200 cortical regions estimated using individual source models. We correlated individually the DFA maps to the distance from the resection area and from cortical locations of interictal epileptiform discharges (IEDs). Additionally, three clinical experts inspected the DFA maps to visually assess the most likely EZ locations. RESULTS: The DFA maps correlated with the distance to resection area in patients with type II focal cortical dysplasia (FCD) (p<0.05), but not in other etiologies. Similarly, the DFA maps correlated with the IED locations only in the FCD II patients. Visual analysis of the DFA maps showed high interobserver agreement and accuracy in FCD patients in assigning the affected hemisphere and lobe. CONCLUSIONS: Aberrant LRTCs correlate with the resection areas and IED locations. SIGNIFICANCE: This methodological pilot study demonstrates the feasibility of approximating cortical LRTCs from MEG that may aid in the EZ localization and provide new non-invasive insight into the presurgical evaluation of epilepsy.

Glioblastoma in a female neurofibromatosis 1 patient without IDH1, BRAF V600E, and TERT promoter mutations: A case report.

RATIONALE: Glioblastoma is the most lethal and common malignant brain tumor but rare in patients with neurofibromatosis type 1. The clinical findings and pathological findings with gene signatures in female patients have not been well clarified. PATIENT CONCERNS: A 51-year-old female patient complained of headache and left limb weakness lasting for 20 days. The patient underwent a cesarean section 20 years ago and hysterectomy 1 year ago because of uterine leiomyomas. Multiple café-au-lait spots and neurofibromas were found over patient's chest, neck, back, and arms. The myodynamia of left distant and proximate epipodite were grade 0 and grade 1 respectively. The myodynamia of lower left limb was grade 3. DIAGNOSES: Magnetic resonance imaging revealed a malignant lesion which was most likely a glioblastoma in the right temporo-parietal lobe, approximately 5.6 × 5.9 × 6.9 cm in size with a rounded boundary. INTERVENTIONS: A right temporo-parietal craniotomy was performed to resect the space-occupying lesion for gross total removal. Then, the patient received concurrent chemoradiotherapy. Histological examination confirmed a glioblastoma without v-RAF murine sarcoma viral oncogene homolog B1 gene, isocitrate dehydrogenase 1 gene, and telomerase reverse transcriptase gene promoter mutations. OUTCOMES: After surgery, the headache was relieved and the muscular strength of left limbs did improve. After receiving the standard treatment regimen, the patient was alive at 13 months follow-up. LESSONS: This is the first reported glioblastoma in female neurofibromatosis type 1 patient without v-RAF murine sarcoma viral oncogene homolog B1 gene, isocitrate dehydrogenase 1 gene, and telomerase reverse transcriptase gene promoter mutations. Tumors in adult patients with these signatures were less aggressive with well-circumscribed border and had long-term survivals which strengthened the evidence that these patients may comprise a unique subset in glioblastoma.

Endoscope-assisted posterior quadrant disconnection plus corpus callosotomy: case report.

Intractable epilepsy impacts many children. Surgically resective and palliative treatments have developed to increase seizure freedom or palliate the seizure burden in those with medically refractory epilepsy. However, surgical epilepsy treatment can confer significant morbidity and death. Endoscope-assisted surgical approaches may be helpful in reducing the morbidity related to traditional open surgical approaches while allowing for good visualization of surgical targets. Here, the authors report a case utilizing an endoscope-assisted keyhole approach to perform a posterior quadrantectomy and corpus callosotomy, achieving the surgical goals of disconnection and reducing the need for large craniotomy exposure. They present the case of a 17-year-old male with medically refractory epilepsy treated with endoscope-assisted posterior quadrantectomy and corpus callosotomy through two mini-craniotomies to achieve a functional disconnection. To the authors' knowledge, this is the first reported case of an endoscope-assisted approach for a posterior quadrantectomy for surgical epilepsy treatment in an adult or a pediatric patient. The case is reported to highlight the technical nuances and benefits of this approach in select patients as well as the expansion of applications of endoscope-assisted epilepsy surgery.