Postoperative Deficits Research Articles

Glioma-induced neural functional remodeling in the hand motor cortex: precise mapping with ECoG grids during awake craniotomy—experimental research

Background: The dilemma of achieving ‘onco-functional balance’ in gliomas affecting the motor cortex highlights the importance of functionally-guided resection strategies. While accurate mapping of eloquent areas often requires frequent electrical stimulation, this practice can lead to side effects like seizures and postoperative deficits. To enhance safety in functional mapping, we studied how gliomas impact hand movement areas and assessed the effectiveness of cortical electrical activity for functional mapping in this setting. Materials and Methods: We recruited patients with gliomas affecting the motor cortex and individuals with an unaffected motor cortex for awake craniotomy. During the procedures, electrocorticography (ECoG) grids were employed to record signals under three conditions: resting state, finger movements, and wrist movements. We then quantified the distances from the positively stimulated sites to the specific anatomical landmarks. Additionally, we analyzed the relationship between the ECoG power features and the stimulation responses. Results: The cortical layout for finger activity in the MCG group was more dispersed and overlapped, typically clustering near the central sulcus and Sylvian fissure. The predictive performance of ECoG mapping exhibited significant variability across different frequency bands and clinical scenarios. Specifically, the area under the curve (AUC) for the Non-MCG group during the resting state reached its peak, with a value of 0.802 for Gamma3 (95% CI = 0.729-0.875) and 0.865 for broadband (95% CI = 0.804-0.926). In contrast, the MCG group achieved the highest AUC during wrist movements, with Gamma3 at 0.785 (95% CI = 0.719-0.849) and broadband at 0.824 (95% CI = 0.753-0.890). Conclusion: Gliomas in the motor cortex disrupt the distribution of hand activity, complicating intraoperative functional mapping. As a novel and reliable approach, ECoG technique can complement and guide direct cortical stimulation for precise mapping, potentially reducing its frequency, minimizing the risk of functional deficits, and achieving a balance between maximal tumor resection and neurological preservation.

Risk factors for motor decline following parasagittal and falx meningioma resection in the middle third

ObjectiveThe resection of parasagittal and falx meningiomas in the middle third superior sagittal sinus (SSS) is associated with a high risk of postoperative motor deficits. This study discusses the risk factors affecting postoperative motor decline and recovery of motor function after follow-up.MethodsThe results of a single-institution retrospective cohort study of parasagittal and falx meningioma resection in the middle third between 2016 and 2023 were reviewed, and parameters were screened as potential predictors. Variables of interest included postoperative motor decline and outcome after follow-up. Univariate and multivariate analyses were performed to identify risk factors.ResultsAmong 87 patients who underwent resection of parasagittal (63.2%) or falx (36.8%) middle third meningiomas, 14.9% (13/87) experienced postoperative motor decline. Among the 36 patients (41.4%) with preoperative motor deficits, 66.3% improved, 17.0% unchanged, and 16.7% (6/36) worsened following surgery. Among the 51 patients without preoperative motor deficits, 13.7% (7/51) developed new weakness. The predictors of postoperative motor decline were major venous involvement (p = 0.022), falx meningioma (p = 0.031), loss of the brain-tumor interface (p=0.033) and WHO grade II-III (p = 0.032).ConclusionsThe resection of parasagittal and falx meningiomas in the middle third carries a high rate of postoperative morbidity and deserves perioperative planning. Alternative surgical strategies, such as preserving the brain-tumor arachnoid interface and minority residual tumors, may prevent motor decline in a subset of high-risk patients.

Pediatric Awake Craniotomy: An Educational Review.

Awake craniotomies with functional cortical mapping are performed to minimize post-operative deficits from the resection of lesions adjacent to eloquent cortex. The procedure is well-established in the adult patient population and is increasingly applied to well-selected pediatric patients. A review of recent literature demonstrated that the most commonly reported anesthetic techniques were "asleep-awake-asleep" protocols that relied on propofol, remifentanil, or fentanyl. This educational review discusses the unique challenges that face the anesthesiology and neurosurgical teams when working with the pediatric population. To further illustrate pediatric-specific considerations, a case of a 9-year-old boy who underwent a resection of a large left peri-rolandic ependymoma is presented, including his multidisciplinary pre-operative, intra-operative, and post-operative care. Awake craniotomies can safely be performed in the pediatric population with appropriate patient sel7ection, planning, and a multi-disciplinary approach.

Long-term surgical outcomes and prognosis of cervical spinal hemangioblastomas.

Hemangioblastomas (HBs) occurring in the cervical spinal region are infrequently reported. Surgical resection of cervical HBs poses a significant challenge, and the long-term therapeutic outcomes remain unclear. A comprehensive retrospective analysis was conducted to review the treatment outcomes of patients with cervical HBs from 2011 to 2021. Patients with detailed preoperative clinical and radiological information, as well as follow-up data, were included in this study. One hundred six adult patients were enrolled, with a mean age of 37.4 ± 15.6 years (range: 18-68 years), and a male predominance of 58.5 %. Thirty-two patients (30.2 %) had von Hippel-Lindau (VHL) disease. VHL-associated patients were younger (p = 0.023), had a shorter duration of symptoms (p = 0.004), and had smaller lesion size (p = 0.039) compared to the sporadic group. Fourteen patients (13.2 %) experienced immediate postoperative deterioration. During long-term follow-up, 35 patients (33.0 %) improved, 57 patients (53.8 %) remained stable. 8 patients (7.5 %) worsened compared to baseline, and 6 patients (5.7 %) died. A recurrent HBs (p = 0.027), ventral location (p = 0.046), and worsened immediately after surgery (p = 0.001) were statistically significant indicators for unfavorable outcomes in multivariate analysis. Surgical resection of cervical spinal HBs can achieve favorable long-term outcomes in most cases, although neurological deterioration may occur immediately after surgery. Postoperative deficits occur in 13.2 % patients, and the incidence of respiratory insufficiency is relatively low. A recurrent HBs, ventral location, and worsened immediately after surgery were indicators for unfavorable outcomes.

No Difference in External Rotation Loss After Isolated Bankart Repair, Remplissage, or Latarjet: A Systematic Review and Meta-analysis.

Despite the effectiveness of remplissage in reducing instability recurrence, debate remains about the loss of external rotation (ER) after this procedure. To compare the loss of ER after primary isolated arthroscopic Bankart repair alone (BR), Bankart with remplissage (REMP), and Latarjet (LAT) procedures. Meta-analysis; Level of evidence, 3. A literature search of 4 databases was conducted to identify comparative studies reporting ER after BR, REMP, or LAT. ER loss with the arm at side was collected, along with postoperative Rowe score, return to previous sport level, instability recurrence, reintervention, and noninstability complications. Dichotomous variables were assessed using odds ratios with 95% CIs, and continuous variables were analyzed using mean differences (MDs) with 95% CIs. A random-effects meta-analysis was used for continuous outcomes and dichotomous outcomes. In total, 27 studies were included, consisting of 2100 patients: 824 in BR, 378 in REMP, and 898 in LAT groups. The mean ER loss was 6.8°± 11° after BR, 9.3°± 12.6° after REMP, and 0.8°± 20.4° after LAT. Comparing REMP and BR, the MD was 5.9° (P = .13); between REMP and LAT, the MD was 9.6° (P = .17). For Rowe scores, the MD was 3.46 (P = .49) between REMP and BR and 0.24 (P = .9) between REMP and LAT. Odds ratios for return to previous sport level were 1.08 (P = .84) for REMP versus BR and 1.62 (P = .09) for REMP versus LAT. Regarding instability recurrence, the odds ratio was 6.67 (P = .04) for REMP versus BR and 1.43 (P = .48) for REMP versus LAT. The odds ratio for reoperation for BR was 7.69 (P = .05) compared with REMP, and the odds ratio for complications for LAT was 6.25 (P = .02) compared with REMP. Remplissage reduces instability recurrence compared with isolated Bankart repair without any statistically significant difference in postoperative ER deficit. Remplissage may reduce the risk of reoperation compared with Latarjet with no difference in postoperative ER deficit or recurrence.

Mid to long term follow up of early weightbearing after open reduction internal fixation of ankle fractures.

Studies have demonstrated successful outcomes with early weightbearing following open reduction internal fixation (ORIF) of specific ankle fractures. The external validity of an early weightbearing protocol and its effects on patient-reported outcome information scores (PROMIS) has yet to be investigated. This study aimed to investigate the effects of an early weightbearing protocol for all operatively treated ankle fractures and its impact on clinical outcomes and complications. This retrospective cohort study included 229 patients (≥ 16 years) with OTA/AO 44 A-C fractures who underwent open reduction and internal fixation (ORIF). Patients were divided into groups based on early (2-3 weeks postoperative) or delayed (>6 weeks postoperative) weightbearing protocols. Primary outcomes included PROMIS score subsets including physical function, depression, and pain interference and ankle range of motion (ROM) at each follow up visit. Secondary outcomes included complications such as implant removal for pain, prominence, or surgical site infection, revision surgery for failure of fixation or loss of reduction, and post-operative sensory or motor deficits. There were 96 patients in the early weightbearing cohort and 133 patients in the delayed weightbearing cohort. The median follow-up time of the early weightbearing cohort was 471.47 ± 389.69 days while the delayed cohort was 459.82 ± 358.21 days. Demographics and comorbidities were distributed equally between both groups, except the presence of peripheral neuropathy which was observed more frequently in the delayed weightbearing cohort (8 versus 0, p = 0.022). Results indicated no statistically significant differences in PROMIS scores at final follow up, ankle ROM, or post-operative complications between the early and delayed weightbearing cohorts. Multivariable regression analysis identified smoking as a factor associated with worse ankle ROM at final follow-up. This study found that early weightbearing after ORIF of unstable ankle fractures leads to similar PROMIS scores and ankle ROM without increased complications. In addition, smokers were found to have worse ankle ROM when compared to nonsmokers at final follow-up.

Risk Factors For Increased External Rotation Deficit After Combined Bankart Repair And Remplissage For Recurrent Anterior Shoulder Instability.

External rotation (ER) deficit following Bankart repair and remplissage (BRR) is reported to be a major concern. The purpose of this study was to identify potential risk factors which correlate with increased postoperative ER deficit in a population which underwent BRR for recurrent anterior shoulder instability and glenoid bone loss (<20%). A retrospective analysis of prospectively collected data was performed on 41 patients who underwent BRR for anterior shoulder instability with glenoid bone loss of < 20%. Inclusion criteria were; a minimum of 2-year postoperative follow-up with available pre and postoperative functional scores (ASES and WOSI) and preoperative MRI. Regression analysis was conducted to detect risk factors for postoperative ER deficit, including age, sex, number of dislocations, length of follow-up, Hill-Sachs interval (HSI), Hill-Sachs depth (HSD), sport participation, number of anchors used for remplissage and hand dominance. A sub-analysis was undertaken after dividing patients into 2 groups (deficit < 20% and ≥ 20%). Correlation between postoperative scores and ER deficit was performed. All patients showed marked improvement in postoperative WOSI and ASES compared to preoperative by a mean difference of 46.2 ± 19.9 and 29.6 ± 14.4 respectively. Compared to the opposite side the mean reduction in external rotation at the side (ERs), external rotation in abduction (ERa), forward flexion (FF) and internal rotations in abduction (IRa) were (21.9% ± 15.5), (14.3% ± 9.9), (2.7% ± 1.9) and (10% ± 6.2) respectively. Univariate regression analysis showed that shorter postoperative time, Larger HSI and the use of two anchors were significantly associated with increased limitation of both ERs and ERa. Participation in sports was significantly associated with less ERs limitation. HSD was significantly associated with increased ERa limitation. Multivariate regression analysis revealed that larger HSI was significantly associated with increased both ERs and ERa limitation. Time of final follow-up and number of anchors were significantly associated with ERs and Era limitation respectively. ≥ 20% ER deficit was significantly associated with lower number of preoperative dislocations, shorter time of final follow-up, HSI, and 2 anchors used in remplissage. No correlation exist between functional scores and ER deficit. There were no recurrent dislocations. The results show that postoperative ER deficit improves over time. Risk factors for increased postoperative ER deficit are larger HSI and when more than one anchor is used for capsulotenodesis. There was no correlation between functional scores and ER deficit.

Sudden Loss of Motor-Evoked Potentials (MEPs) During the Resection of A Nondominant Insular Glioma: Case Report and Management Review.

A 43-year-old man was admitted into the emergency room at our hospital after presenting with a tonic-clonic seizure. MRI showed a right-side operculo-insular tumor. This was treated by performing a craniotomy under general anesthesia with intraoperative monitoring. Tumor resection was started by exploring the temporal and frontal opercula without problems. However, during the resection of the insular compartment, a sudden loss of MEPs was observed. Surgery was stopped immediately, and all the relevant anesthetic parameters, vital signs, anesthetic drugs were reviewed. No retractors had been used at that time, so vasospasm was suspected as the underlying cause of the signal change. An ICG bolus injection confirmed vasospasm in one of the M2 branches running over the insula. A direct vessel massage was performed yet resulted in no apparent improvement in the appearance of the vessel when ICG was injected. Therefore, repeated massage with nimodipine was performed, which resulted in the resolution of the vasospasm. MEPs progressively recovered to base line levels, and surgery could then be finished without further incident. During the postoperative recovery period, no focal deficit was identified, and the postoperative MRI showed a planned subtotal resection without apparent ischemia. The goal of this report is to review the potential causes of such a loss of intraoperative MEPs and its best management in order to prevent postoperative motor deficit and to manage the situation should it occur.

Comparative analysis of intraoperative thermal and optical imaging for identification of the human primary sensory cortex.

The precise identification and preservation of functional brain areas during neurosurgery are crucial for optimizing surgical outcomes and minimizing postoperative deficits. Intraoperative imaging plays a vital role in this context, offering insights that guide surgeons in protecting critical cortical regions. We aim to evaluate and compare the efficacy of intraoperative thermal imaging (ITI) and intraoperative optical imaging (IOI) in detecting the primary somatosensory cortex, providing a detailed assessment of their potential integration into surgical practice. Data from nine patients undergoing tumor resection in the region of the somatosensory cortex were analyzed. Both IOI and ITI were employed simultaneously, with a specific focus on the areas identified as the primary somatosensory cortex (S1 region). The methodologies included a combination of imaging techniques during distinct phases of rest and stimulation, confirmed by electrophysiological monitoring of somatosensory evoked potentials to verify the functional areas identified by both imaging methods. The data were analyzed using a Fourier-based analytical framework to distinguish physiological signals from background noise. Both ITI and IOI successfully generated reliable activity maps following median nerve stimulation. IOI showed greater consistency across various clinical scenarios, including those involving cortical tumors. Quantitative analysis revealed that IOI could more effectively differentiate genuine neuronal activity from artifacts compared with ITI, which was occasionally prone to false positives in the presence of cortical abnormalities. ITI and IOI produce comparable functional maps with moderate agreement in Cohen's kappa values. Their distinct physiological mechanisms suggest complementary use in specific clinical scenarios, such as cortical tumors or impaired neurovascular coupling. IOI excels in spatial resolution and mapping reliability, whereas ITI provides additional insights into metabolic changes and tissue properties, especially in pathological areas. Combined, these modalities could enhance the understanding and analysis of functional and pathological processes in complex neurosurgical cases.

DNMT3a Deficiency Contributes to Anesthesia/Surgery-Induced Synaptic Dysfunction and Cognitive Impairment in Aged Mice.

Perioperative neurocognitive disorder (PND) is a severe postoperative complication in older patients. Epigenetic changes are hallmarks of senescence and are closely associated with cognitive impairment. However, the effects of anesthesia and surgery on the aging brain's epigenetic regulatory mechanisms and its impact on cognitive impairment remain unclear. Using a laparotomy PND model, we report significant reduction in DNA methyltransferase 3a (DNMT3a) in hippocampal neurons of aged mice, which causes global DNA methylation decrease. Knockdown of DNMT3a leads to synaptic disorder and memory impairment in aged mice. Mechanistically, bisulfite sequencing revealed that DNMT3a deficiency reduces methylation in the LRG1 promoter region and promotes its transcription. We also show that activation of TGF-β signaling by the increase in LRG1 level, ultimately impacts the synaptic function. In contrast, both overexpressing DNMT3a or knockdown LRG1 in hippocampus can attenuate the synaptic disorders and rescue postoperative cognitive deficits in aged mice. Our results reveal that DNMT3a is a previously undefined mediator in the pathogenesis of PND, which couples epigenetic regulations with anesthesia/surgery-induced synaptic dysfunction and represents a therapeutic target to tackle PND.

Mini-strokes within Broca-caudate connections during left insular glioma awake surgery cause transient severe naming deficits.

To provide an explanation for the intraoperative onset of severe naming deficits in the course of awake resection of left insular glioma. We retrospectively reviewed a series of 14 patients operated on in awake conditions for a left insular IDH-mutated glioma. Preoperative MRI included high-resolution diffusion sequences, to which constrained spherical deconvolution pipeline was applied, to obtain a whole brain tractogram. Whole brain T1 parcellation was obtained by Freesurfer, allowing to dissect the tractogram and identify the connections between the caudate nucleus and Broca's area. Postoperative MRI standard diffusion the day after surgery was performed, allowing to delineate and register to the preoperative MRI any area of hyperintense diffusion with low apparent diffusion coefficient. The pathway between pars triangularis (resp. opercularis) and Broca's area were considered as damaged whenever more than 50% of streamlines were passing through the mini-strokes. Patients' language abilities (including a picture naming task) were assessed and reported before, during and after surgery by certified speech therapists. Severe postoperative naming deficits were defined as a score lower than 40/80 items. Contingency tables were analyzed with Fisher exact test (statistical significance set at 0.05). Out the 14 patients, 8 patients had a mini-stroke on the immediate postoperative MRI. None of the 6 patients without any stroke had postoperative naming severe deficits. Five out the 8 patients with a mini-stroke had a severe postoperative naming deficit, characterized by strong verbal perseverations. This difference was statistically significant (exact Fisher test, p = 0.03). For the five patients with a deficit, the mini-stroke damaged either the pars triangularis - caudate pathway or the pars opercularis - caudate pathway, whenever the pars triangularis was resected after negative cortical mapping. For the three patients without severe postoperative naming deficit, the mini-stroke spared the Broca-caudate pathway. All patients recovered quasi-normal naming abilities at the 4-month postoperative evaluation. The occurrence of mini-strokes within the connections between Broca's area and the caudate nucleus explains the sudden naming deficits observed intraoperatively in some patients during awake resection of IDH-mutated insular glioma. Further studies are needed to better predict such event and to assess its impact on other cognitive functions.

Microglia in the aged brain develop a hypoactive molecular phenotype after surgery

BackgroundMicroglia, the resident immune cells of the brain, play a crucial role in maintaining homeostasis in the central nervous system (CNS). However, they can also contribute to neurodegeneration through their pro-inflammatory properties and phagocytic functions. Acute post-operative cognitive deficits have been associated with inflammation, and microglia have been implicated primarily based on morphological changes. We investigated the impact of surgery on the microglial transcriptome to test the hypothesis that surgery produces an age-dependent pro-inflammatory phenotype in these cells.MethodsThree-to-five and 20-to-22-month-old C57BL/6 mice were anesthetized with isoflurane for an abdominal laparotomy, followed by sacrifice either 6 or 48 h post-surgery. Age-matched controls were exposed to carrier gas. Cytokine concentrations in plasma and brain tissue were evaluated using enzyme-linked immunosorbent assays (ELISA). Iba1+ cell density and morphology were determined by immunohistochemistry. Microglia from both surgically treated mice and age-matched controls were isolated by a well-established fluorescence-activated cell sorting (FACS) protocol. The microglial transcriptome was then analyzed using quantitative polymerase chain reaction (qPCR) and RNA sequencing (RNAseq).ResultsSurgery induced an elevation in plasma cytokines in both age groups. Notably, increased CCL2 was observed in the brain post-surgery, with a greater change in old compared to young mice. Age, rather than the surgical procedure, increased Iba1 immunoreactivity and the number of Iba1+ cells in the hippocampus. Both qPCR and RNAseq analysis demonstrated suppression of neuroinflammation at 6 h after surgery in microglia isolated from aged mice. A comparative analysis of differentially expressed genes (DEGs) with previously published neurodegenerative microglia phenotype (MGnD), also referred to disease-associated microglia (DAM), revealed that surgery upregulates genes typically downregulated in the context of neurodegenerative diseases. These surgery-induced changes resolved by 48 h post-surgery and only a few DEGs were detected at that time point, indicating that the hypoactive phenotype of microglia is transient.ConclusionsWhile anesthesia and surgery induce pro-inflammatory changes in the plasma and brain of mice, microglia adopt a homeostatic molecular phenotype following surgery. This effect seems to be more pronounced in aged mice and is transient. These results challenge the prevailing assumption that surgery activates microglia in the aged brain.

Does persistent crossover (ipsilateral) motor evoked potential (MEP) responses represent a technical failure for intracranial motor tract monitoring? A case example and practical solution.

Attention to motor evoked potential (MEP) stimulation intensity is necessary to avoid false negative MEP results during intracranial procedures. Observing ipsilateral (crossover) MEP responses has been hypothesized to indicate inappropriately strong stimulation intensity. We describe a case where persistent crossover MEP responses falsely suggested that stimulus intensity was too high and describe an alternative method to guide the selection of MEP stimulation intensity. A patient undergoing a suboccipital craniotomy for tumor resection had bilateral transcranial electrical MEP monitoring under total intravenous anesthesia. MEP results were obtained from left and right hand using C4-Cz and C3-Cz stimulation montages respectively. Selection of an appropriately superficial stimulus intensity was guided using MEP onset latencies. MEP acquisition proceeded normally for contralateral left hand (C4-Cz montage). However, using the C3-Cz montage, persistent crossover responses were noted at stimulation intensities as low as threshold for contralateral right hand MEP (94V/166mA). Appropriate MEP stimulus intensity for subsequent monitoring (approximately 96V/172mA) was determined utilizing onset latency measurements from contralateral hand MEP responses. The stimulus intensity chosen was predicated on onset latency being ≥ 2 ms longer than latency at maximal stimulus level (shortest latency). A stimulus intensity-latency plot was generated offline to illustrate this important relationship for intracranial MEP use. MEP acquisition proceeded without incident and gross total resection was achieved without postoperative motor deficits. Despite crossover appearance contralateral hand MEP were quantitatively validated for intraoperative application using onset latency guidance.

Epilepsy surgery in children with operculoinsular epilepsy: Results of a large unicentric cohort.

Epilepsy surgery in the operculoinsular cortex is challenging due to the difficult delineation of the epileptogenic zone and the high risk of postoperative deficits. Pre- and postsurgical data from 30 pediatric patients who underwent operculoinsular cortex surgery at the Motol Epilepsy Center Prague from 2010 to 2022 were analyzed. Focal cortical dysplasia (FCD; n = 15, 50%) was the predominant cause of epilepsy, followed by epilepsy-associated tumors (n = 5, 17%) and tuberous sclerosis complex (n = 2, 7%). In eight patients where FCD was the most likely etiology, the histology was negative. Seven patients (23%) displayed normal magnetic resonance imaging results. Seizures exhibited diverse semiology and propagation patterns (frontal, perisylvian, and temporal). The ictal and interictal electroencephalographic (EEG) findings were mostly extensive. Multimodal imaging and advanced postprocessing were frequently used. Stereo-EEG was used for localizing the epileptogenic zone and eloquent cortex in 23 patients (77%). Oblique electrodes were used as guides for better neurosurgeon orientation. The epileptogenic zone was in the dominant hemisphere in 16 patients. At the 2-year follow-up, 22 patients (73%) were completely seizure-free, and eight (27%) experienced a seizure frequency reduction of >50% (International League Against Epilepsy class 3 and 4). Fourteen patients (47%) underwent antiseizure medication tapering; treatment was completely withdrawn in two (7%). Nineteen patients (63%) remained seizure-free following the definitive outcome assessment (median = 6 years 5 months, range = 2 years to 13 years 5 months postsurgery). Six patients (20%) experienced corona radiata or basal ganglia ischemia; four (13%) improved to mild and one (3%) to moderate hemiparesis. Two patients (7%) operated on in the anterior insula along with frontotemporal resection experienced major complications: pontine ischemia and postoperative brain edema. Epilepsy surgery in the operculoinsular cortex can lead to excellent patient outcomes. A comprehensive diagnostic approach is crucial for surgical success. Rehabilitation brings a great chance for significant recovery of postoperative deficits.

Cerebral cavernous malformation with prolonged postoperative paralysis due to perilesional inflammation: illustrative case.

Postoperative symptom exacerbation after resection of cerebral cavernous malformations (CCMs) is usually due to surgical damage to the eloquent areas or venous outflow obstruction from injury to a developmental venous anomaly (DVA). A 21-year-old right-handed female presented with headache, right limb weakness, and aphasia. Magnetic resonance imaging (MRI) revealed a 3.5-cm CCM with significant perilesional edema in the middle frontal gyrus. Despite medical treatment, her weakness worsened, necessitating emergency resection. Imaging revealed no DVA or venous obstructions. Histopathological examination revealed marked neutrophil infiltration, indicating noninfectious inflammation. One week postoperatively, MRI revealed increased edema around the resection site. Although the aphasia improved, paralysis (manual muscle testing grade 3) persisted, prompting betamethasone administration. The symptoms rapidly improved over 10 days, and the patient was discharged symptom free on day 20 with no recurrence thereafter. Patients with prolonged postoperative deficits after CCM resection can experience noninfectious inflammation. Anti-inflammatory treatments such as corticosteroids may be necessary in similar cases with poor recovery from edema and symptoms. https://thejns.org/doi/10.3171/CASE24570.

Neuro-oncology application of next-generation, optically tracked robotic stereotaxis with intraoperative computed tomography: a pilot experience.

Innovations in robotics continue to reshape the landscape of neurosurgery. Here, the authors evaluated the safety and efficacy of the ExcelsiusGPS robot in the treatment of neuro-oncological, intracranial lesions. The authors conducted a retrospective analysis of 19 consecutive adult patients with a neuro-oncological diagnosis who underwent intracranial biopsy and/or laser interstitial thermal therapy (LITT) with the assistance of the ExcelsiusGPS robot and intraoperative CT. Demographic and clinical data were collected from the electronic medical record and the robot software. All 19 patients harbored lesions that were deep seated, involving the eloquent cortex, or subcentimeter. Definitive tissue diagnosis was achieved in all cases involving stereotactic biopsy (n = 16), with glioblastoma as the most common diagnosis. The mean ± SD time for setting up the robotic stereotaxis system was 57.4 ± 10.7 minutes. The mean procedural time after that was 71.6 ± 41.0 minutes for stereotactic needle biopsy and 188.4 ± 61.2 minutes for procedures involving LITT. The mean radial errors of the actual trajectory relative to the planned trajectory at the entry and target points were 0.625 ± 0.443 mm and 0.745 ± 0.472 mm, respectively. There were no procedural complications or new postoperative deficits, although routine postoperative CT showed new hyperdensity at the target site in 3/19 patients (15.7%). All patients who underwent elective procedures were discharged by postoperative day 3 (mean 1.38 ± 0.619 days). There were two 30-day readmissions (pulmonary embolus and general weakness), and neither was attributable to the surgical procedure. The authors' pilot experience with the ExcelsiusGPS robot in neuro-oncology procedures indicates a favorable efficacy and safety profile.

An examination of seizure-free outcome and visual field deficits: Anterior temporal lobectomy versus selective amygdalohippocampectomy for temporal lobe epilepsy-a systematic review and meta-analysis for comprehensive understanding.

This study compares Selective Amygdalohippocampectomy (SAHE) and Anterior Temporal Lobectomy (ATL) for temporal lobe epilepsy (TLE), focusing on seizure control and visual field deficits (VFD). While previous research suggests potential benefits of SAHE, this meta-analysis aims to clarify the comparative effectiveness of bothprocedures. This study adhered to PRISMA guidelines, comparing seizure outcomes and VFDs between SAHE and ATL for temporal lobe epilepsy. Comprehensive data extraction and meta-analysis revealed comparable efficacy, with SAHE potentially offering advantages in VFD risk reduction. Quality assessment ensured methodological rigor. 29 studies comparing SAHE and ATL for TLE. Seizure freedom analysis encompassed 23 studies (n = 3238), showing no significant difference between SAHE and ATL (RR = 0.96, 95% CI = 0.89-1.03, P = 0.26). SAHE exhibited significantly lower visual field deficits (RR = 0.87, 95% CI = 0.78-0.97, P = 0.01). Subgroup analyses highlighted differences between transsylvian SAHE and ATL but not transcortical SAHE. No significant difference was found in seizure freedom between SAHE and ATL in patients with hippocampal sclerosis. ATL is more effective than transsylvian SAHE in achieving seizure freedom. However, no significant difference in seizure freedom was observed between transcortical SAHE and ATL. There were no notable differences in seizure outcomes between the two techniques in patients with hippocampal sclerosis. In contrast, SAHE carries a lower risk of postoperative visual field deficits compared to ATL.

Resection of Calcified and Giant Thoracic Disc Herniation Through Bilateral Postero-Lateral Approach and 360° Cord Release: A Technical Note.

Background/Objectives: Surgical treatment of thoracic disc herniation (TDH) is risky and technically demanding due to its proximity to the spinal cord and the high possibility of the TDH being calcified (up to 40%), making the resection even more complex. Calcified TDH may be resected from an anterior via thoracotomy/thoracoscopy, lateral extra-cavitary, or a postero-lateral approach. Here, we present our experience in managing such pathology with an original technique Methods: This original technique, used successfully in more than 40 patients, is introduced, with a precise description of the surgical anatomy and the surgical steps to take. Indications for surgical management and neurological outcomes are also analyzed. This surgical approach consisted of transverso-pediculectomy, most often bilaterally, partial vertebral body drilling, 360° release of the cord, and short fixation. Results: A total of 44 patients were collected, with a mean age of 52.4 ± 11.7 years. Seven patients (15.9%) had complete calcifications, and thirty-one had partial calcifications (70.5%), while the remaining six did not have signs of calcifications. There were only 4 intraoperative complications (2 dural tears and 2 loss of evoked potentials). The TDH could be resected in total for 39 patients (88.6%) and partially, according to the "floating" technique, in 5 patients (11.4%). In the postoperative follow-up, all of the patients except two (presenting with sensory aggravation) reported an improvement in neurological conditions leading to an overall risk of neurological aggravation of 4.5%. Conclusions: The bilateral postero-lateral approach provides a large decompression of the cord (360°) and gives safe access to the TDH, even calcified, permitting high rates of total resection. It also prevents any prejudicial pressure on the spinal cord, reducing the risk of severe postoperative deficits and permitting optimal instrumentation (pedicle screw-based) of the spinal segment. The surgical sequence to resect the bony structures around the spinal cord is of great importance.

CNSC-05. MAPPING LANGUAGE PROCESSING IN SURGICAL GLIOMA PATIENTS

Abstract Previous work from our group has shown that the resection of white matter tracts localized by transcranial magnetic stimulation (TMS) predicts postoperative neurological deficits. Here we use advanced preoperative brain mapping along with formal language evaluations to localize the neuroanatomical underpinnings of language processing in surgical glioma patients. In patients who had TMS tracts resected, the resected portions (“tract-cavity segmentations”) were classified according to the functional outcome (“true positives”-corresponding deficit; “false positives”-no deficit) and normalized to MNI space. For patients who sustained long-term deficits, TMS tracts were segmented according to spatial overlap with normative tracts to create ROIs. Each normalized resection cavity (n=79) was analyzed for overlap with each ROI associated with postoperative deficits (n=8). The percentage of patients who had positive ROI resections that included TMS tracts versus patients who had positive ROI resections irrespective of TMS tracts were analyzed according to the percent who sustained deficits in each group. ROIs from all patients were summed to create a probabilistic atlas of functional white matter. “True positive” tract-cavity segmentations localized into dual anterior/posterior “hubs” and demonstrated significantly higher spatial association with normative tracts across three different measures (p&amp;lt;.05). 92% of patients who underwent ROI resections that included TMS tracts sustained long-term deficits while 34% of patients who underwent ROI resections irrespective of individualized mapping sustained deficits (p&amp;lt;.05). The probabilistic atlas of functional white matter demonstrated significantly higher voxel intensities within the white matter deep to the temporoparietal junction defined by the same posterior “hub” ROI from Figure 1 (p&amp;lt;.001). This study demonstrates that essential language processing localizes to ROIs within normative white matter tracts that require individualized mapping for surgical preservation. The white matter deep to the temporoparietal junction serves as a crucial hub for language-processing circuitry in glioma patients.

INNV-28. CONNECTOMICS-GUIDED GLIOMA RESECTION: HOW CHANGES IN STRUCTURAL CONNECTIVITY CORRELATE WITH LANGUAGE FUNCTION

Abstract Postoperative aphasia is a risk inherent to resections of brain masses in language eloquent areas. Neurosurgical strategies to minimize damage of functional language structures include awake craniotomies combined with stimulation mapping and intra-operative speech and language pathology (SLP) testing. Until now, consideration of white matter tracts involved in language processing as measured by diffusion tensor imaging (DTI) has been minimally incorporated into resection planning. In addition, there is limited understanding as to the association between specific tracts and aphasia risk. Quicktome™ by Omniscient Neurotechnology is clinically-oriented connectomics software that uses DTI sequences from MRIs to model connectivity between geographically distinct brain regions. This model can then be integrated with intraoperative navigation to avoid language connections during resection. Here, we investigate how language tract changes affect clinical aphasia. Patients with language-eloquent gliomas with available pre- and post-operative DTI and SLP evaluations were included in this retrospective study. Structural networks were quantified using Quicktome™ and compared using Spearman correlation. Changes in language function were evaluated using the Boston Naming Test and the Western Aphasia Battery. Patients with postoperative auditory verbal deficits showed a moderate correlation in connectivity changes (ρ=0.42), whereas patients with postoperative naming deficits showed a weak correlation (ρ=0.19). The inferior frontal junction, anterior portion (IFJa), and the superior temporal sulcus, ventral posterior portion (STSvp), in the right hemisphere demonstrated the most associated structural connectivity changes. To our knowledge, this is the first study which uses Quicktome™ to directly associate postoperative connectivity with aphasia outcomes. Understanding the interplay between structural connectivity and neurological symptoms can elucidate neural pathways underlying cortical function with the potential to reduce neurosurgical postoperative morbidity.