Intracranial-Intracranial Bypass Using a Y-Shaped Artery Graft for Growing Unruptured Gemella morbillorum Infectious Aneurysm on Artery Supplying Sensory Cortex.

BACKGROUND: Vascular reconstruction is required to treat infectious intracranial aneurysms (IIAs) on arteries supplying the eloquent area. However, extracranial-intracranial bypass is sometimes impossible because IIAs are frequently located distally on arteries and the length of a donor artery is limited. We report a rare case of an unruptured Gemella morbillorum IIA, which was successfully treated by intracranial-intracranial (IC-IC) bypass using a Y-shaped superficial temporal artery (STA) interposition graft. CASE DESCRIPTION: A 52-year-old man presented with heart failure and an unruptured IIA in the right anterior parietal artery because of acute G. morbillorum endocarditis. The patient was treated with urgent replacement of cardiac valves and antibiotic therapy. However, the IIA increased in size during the following 1 month, and therefore was treated surgically to prevent the rupture. End-to-side IC-IC bypass using a Y-shaped STA graft followed by aneurysmal trapping was performed to overcome the limited length of the STA as a donor artery to prevent cerebral ischemia in the artery territory and to avoid direct injury to the sensory cortex adhering tightly to the IIA. Postoperative courses were uneventful, and he recovered from the infectious diseases. CONCLUSIONS: This case suggests that end-to-side IC-IC bypass using a Y-shaped STA graft can be a good option for surgical treatment of IIAs, which are located in eloquent areas.

Electrical stimulation sensorimotor mapping with stereo-EEG.

OBJECTIVE: We evaluated stereo-EEG electrical stimulation mapping (ESM) for localization of anatomic sensorimotor parcels in pediatric patients with drug-resistant epilepsy. We also analyzed sensorimotor and after-discharge thresholds, and the somatotopy of sensorimotor responses. METHODS: ESM was performed with 50 Hz, biphasic, 2-3 s trains, using 1-9 mA current. Pre- and post-implant neuroimaging was co-registered and intersected with Neurosynth reference, to classify each electrode contact as lying within/outside an anatomic sensorimotor parcel. Indices of diagnostic performance were computed. Sensorimotor and after-discharge thresholds were analyzed using multivariable linear mixed models. RESULTS: In 15 patients (6 females), aged 5.5-21.2 years, ESM showed high accuracy (0.80), high specificity (0.86), and diagnostic odds ratio (11.4, p < 0.0001) for localization of sensorimotor parcels. Mean sensorimotor threshold (3.4 mA) was below mean after-discharge threshold (4.2 mA, p = 0.0004). Sensorimotor and after-discharge thresholds showed a significant decrease with increasing intelligence quotient. Somatotopy of sensorimotor responses was mapped to standardized brain parcels. CONCLUSIONS: We provide evidence for diagnostic validity and safety of stereo-EEG sensorimotor ESM. SIGNIFICANCE: The somatotopy of sensorimotor responses elicited with electrical stimulation provide new insights into mechanisms of motor control and sensory perception.

An exoskeleton controlled by an epidural wireless brain-machine interface in a tetraplegic patient: a proof-of-concept demonstration.

BACKGROUND: Approximately 20% of traumatic cervical spinal cord injuries result in tetraplegia. Neuroprosthetics are being developed to manage this condition and thus improve the lives of patients. We aimed to test the feasibility of a semi-invasive technique that uses brain signals to drive an exoskeleton. METHODS: We recruited two participants at Clinatec research centre, associated with Grenoble University Hospital, Grenoble, France, into our ongoing clinical trial. Inclusion criteria were age 18-45 years, stability of neurological deficits, a need for additional mobility expressed by the patient, ambulatory or hospitalised monitoring, registration in the French social security system, and signed informed consent. The exclusion criteria were previous brain surgery, anticoagulant treatments, neuropsychological sequelae, depression, substance dependence or misuse, and contraindications to magnetoencephalography (MEG), EEG, or MRI. One participant was excluded because of a technical problem with the implants. The remaining participant was a 28-year-old man, who had tetraplegia following a C4-C5 spinal cord injury. Two bilateral wireless epidural recorders, each with 64 electrodes, were implanted over the upper limb sensorimotor areas of the brain. Epidural electrocorticographic (ECoG) signals were processed online by an adaptive decoding algorithm to send commands to effectors (virtual avatar or exoskeleton). Throughout the 24 months of the study, the patient did various mental tasks to progressively increase the number of degrees of freedom. FINDINGS: Between June 12, 2017, and July 21, 2019, the patient cortically controlled a programme that simulated walking and made bimanual, multi-joint, upper-limb movements with eight degrees of freedom during various reach-and-touch tasks and wrist rotations, using a virtual avatar at home (64·0% [SD 5·1] success) or an exoskeleton in the laboratory (70·9% [11·6] success). Compared with microelectrodes, epidural ECoG is semi-invasive and has similar efficiency. The decoding models were reusable for up to approximately 7 weeks without recalibration. INTERPRETATION: These results showed long-term (24-month) activation of a four-limb neuroprosthetic exoskeleton by a complete brain-machine interface system using continuous, online epidural ECoG to decode brain activity in a tetraplegic patient. Up to eight degrees of freedom could be simultaneously controlled using a unique model, which was reusable without recalibration for up to about 7 weeks. FUNDING: French Atomic Energy Commission, French Ministry of Health, Edmond J Safra Philanthropic Foundation, Fondation Motrice, Fondation Nanosciences, Institut Carnot, Fonds de Dotation Clinatec.

Laser Ablation Therapy for Pediatric Patients with Intracranial Lesions in Eloquent Areas.

BACKGROUND: Laser interstitial thermal therapy (LITT) is an alternative, less-invasive, and, in some circumstances, effective treatment for patients with intracranial pathology including epilepsy and some tumors. For intracranial lesions in eloquent areas, resection by conventional craniotomy proves often to be a challenge, including in the care of pediatric patients. Herein, we reviewed our experience with magnetic resonance imaging (MRI)-guided LITT as treatment for pediatric patients with intracranial lesions in eloquent areas and evaluate neurologic function and clinical outcomes. METHODS: We retrospectively reviewed consecutive patients with intracranial lesions in eloquent speech and motor areas who underwent MRI-guided LITT. Clinical evaluation, including neurologic function and neuropsychological testing, was conducted according to clinical considerations. MRI pre- and postoperative imaging was reviewed to compare the change of lesion size. RESULTS: Five pediatric patients received MRI-guided LITT of intracranial lesions in eloquent cortex. One patient experienced complications secondary to MRI-guided LITT, but neither was discharged with a neurologic deficit. CONCLUSIONS: For intracranial lesions in the eloquent cortex, conventional craniotomy with surgical resection is a challenge for neurosurgeons, especially pediatric patients. MRI-guided LITT provides a less-invasive and potentially effective option for treatment in the management of pediatric epilepsy and tumors.

Preoperative localization of the sensorimotor cortex and measurement of tumor perfusion in a single acquisition using ASL technique.

Resting state fMRI (rs-fMRI) using arterial spin labelling (ASL) technique was performed for the preoperative localization of the sensorimotor cortex in a patient with lymphoma and the results were compared to those of task-based (tb) and rs-fMRI studies using blood oxygenation level-dependent (BOLD) sequence. Rs-fMRI using ASL showed similar results in the regions of the sensorimotor network to those of tb- and rs-fMRI fMRI using BOLD. ASL technique has a potential in clinical practice because all of brain perfusion imaging, cerebral blood flow measurement, and rs-fMRI study can be performed at a single acquisition.

Supratentorial Cavernous Malformations Involving the Corticospinal Tract and Sensory Motor Cortex: Treatment Strategies, Surgical Considerations, and Outcomes.

BACKGROUND: Cavernous malformations (CMs) are congenital malformations and may be located anywhere in the brain. We present a series of CMs located close to or inside of the motor-sensory cortex or corticospinal tract (CST) with clinical onset due to hemorrhage or mass effect. In such cases, surgery becomes an acceptable option. OBJECTIVE: To evaluate the role of diffusion tensor imaging (DTI), functional-magnetic-resonance imaging (fMRI), intraoperative neurophysiological monitoring, neuronavigation, and brain-mapping and the clinical results of surgical treatment of CMs in this critical location. METHODS: The study included 54 patients harboring 22 cortical and 32 deep locations. This series was distinct because in group I, where the DTI was not obtained, and in the group II, where this evaluation was performed. RESULTS: The postoperative permanent morbidity rate was 4% in the historical group for the deeper CMs, and there was no morbidity in the second group. DTI and fMRI permitted us to estimate the distance between the CMs and both the cortical activation cluster and the pyramidal tract. These data, in addition to intraoperative mapping and monitoring, made it necessary for us to perform a partial resection in 2 cases in the second series. CONCLUSION: CMs are congenital lesions and CST fibers can run directly on their surface. Integration of fMRI and DTI data with intraoperative functional monitoring and direct cortical and subcortical mapping are mandatory to accomplish an optimal resection, tailoring the best surgical approach to the acceptable morbidity. A subtotal resection could be considered an option for deep locations.

Multi-scale, multi-modal analysis uncovers complex relationship at the brain tissue-implant neural interface: new emphasis on the biological interface.

OBJECTIVE: Implantable neural electrode devices are important tools for neuroscience research and have an increasing range of clinical applications. However, the intricacies of the biological response after implantation, and their ultimate impact on recording performance, remain challenging to elucidate. Establishing a relationship between the neurobiology and chronic recording performance is confounded by technical challenges related to traditional electrophysiological, material, and histological limitations. This can greatly impact the interpretations of results pertaining to device performance and tissue health surrounding the implant. APPROACH: In this work, electrophysiological activity and immunohistological analysis are compared after controlling for motion artifacts, quiescent neuronal activity, and material failure of devices in order to better understand the relationship between histology and electrophysiological outcomes. MAIN RESULTS: Even after carefully accounting for these factors, the presence of viable neurons and lack of glial scarring does not convey single unit recording performance. SIGNIFICANCE: To better understand the biological factors influencing neural activity, detailed cellular and molecular tissue responses were examined. Decreases in neural activity and blood oxygenation in the tissue surrounding the implant, shift in expression levels of vesicular transporter proteins and ion channels, axon and myelin injury, and interrupted blood flow in nearby capillaries can impact neural activity around implanted neural interfaces. Combined, these tissue changes highlight the need for more comprehensive, basic science research to elucidate the relationship between biology and chronic electrophysiology performance in order to advance neural technologies.

Practical prognostic score for predicting the extent of resection and neurological outcome of gliomas in the sensorimotor area.

OBJECTIVE: In this prospective study, we assessed the utility of a novel prognostic score (PS) in guiding the surgical strategy of patients with sensorimotor area gliomas. PATIENTS AND METHODS: Form December 2012 to April 2016, we collected data from patients diagnosed with brain gliomas in the sensorimotor area. All the patients had intraoperatively confirmed contiguity or continuity with sensorimotor cortical and subcortical structures. Several clinical and radiological factors were analyzed to generate a PS for each patient (range 1-8). The end-points included the extent of resection (EOR) and neurological outcome (modified Rankin Score; mRS). We assessed the predictive power of the PS using different analyses. Crosstabs analyses and Fisher's exact test (Fet) were used to evaluate the possible predictive parameters, and for the classification of positive or negative outcomes for the chosen proxies; the significance threshold was set at p<0.05. RESULTS: Using independent t-tests, we compared the mRS at different time points (pre, post, and at 6 months) for 2 subgroups from the total sample using a cut-off PS value of 4. For the EOR, a PS value of ≥5 was predictive of successful outcome, a value of 4 indicated an uncertain outcome, and a value of ≤3 predicted a worse outcome. CONCLUSIONS: This PS value can be easily used in clinical settings to help predict the functional outcome and EOR in sensorimotor area tumors. Integration with information from fMRI, DTI, and TMS, along with MRI spectroscopy could further enhance the value of this PS.

Functional Magnetic Resonance Imaging (fMRI), Pre-intraoperative Tractography in Neurosurgery: The Experience of Sant' Andrea Rome University Hospital.

BACKGROUND: The goal of neurosurgery for cerebral intraparenchymal neoplasms of the eloquent areas is maximal resection with the preservation of normal functions, and minimizing operative risk and postoperative morbidity. Currently, modern technological advances in neuroradiological tools, neuronavigation, and intraoperative magnetic resonance imaging (MRI) have produced great improvements in postoperative morbidity after the surgery of cerebral eloquent areas. The integration of preoperative functional MRI (fMRI), intraoperative MRI (volumetric and diffusion tensor imaging [DTI]), and neuronavigation, defined as "functional neuronavigation" has improved the intraoperative detection of the eloquent areas. METHODS: We reviewed 142 patients operated between 2004 and 2010 for intraparenchymal neoplasms involving or close to one or more major white matter tracts (corticospinal tract [CST], arcuate fasciculus [AF], optic radiation). All the patients underwent neurosurgery in a BrainSUITE equipped with a 1.5 T MR scanner and were preoperatively studied with fMRI and DTI for tractography for surgical planning. The patients underwent MRI and DTI during surgery after dural opening, after the gross total resection close to the white matter tracts, and at the end of the procedure. We evaluated the impact of fMRI on surgical planning and on the selection of the entry point on the cortical surface. We also evaluated the impact of preoperative and intraoperative DTI, in order to modify the surgical approach, to define the borders of resection, and to correlate this modality with subcortical neurophysiological monitoring. We evaluated the impact of the preoperative fMRI by intraoperative neurophysiological monitoring, performing "neuronavigational" brain mapping, following its data to localize the previously elicited areas after brain shift correction by intraoperative MRI. RESULTS: The mean age of the 142 patients (89 M/53 F) was 59.1 years and the lesion involved the CST in 66 patients (57 %), the language pathways in 24 (21 %), and the optic radiations in 25 (22 %). The integration of tractographic data into the volumetric dataset for neuronavigation was technically possible in all cases. In all patients intraoperative DTI demonstrated a shift of the bundle position caused by the surgical procedure; its dislocation was both outward and inward in the range of +6 mm and -2 mm. CONCLUSION: We found a high concordance between fMRI/DTI and intraoperative brain mapping; their combination improves the sensitivity of each technique, reducing pitfalls and so defining "functional neuronavigation", increasing the definition of eloquent areas and also reducing the time of surgery.

Presurgical Assessment of the Sensorimotor Cortex Using Resting-State fMRI.

BACKGROUND AND PURPOSE: The functional characterization of the motor cortex is an important issue in the presurgical evaluation of brain lesions. fMRI noninvasively identifies motor areas while patients are asked to move different body parts. This task-based approach has some drawbacks in clinical settings: long scanning times and exclusion of patients with severe functional or neurologic disabilities and children. Resting-state fMRI can avoid these difficulties because patients do not perform any goal-directed tasks. MATERIALS AND METHODS: Nineteen patients with diverse brain pathologies were prospectively evaluated by using task-based and resting-state fMRI to localize sensorimotor function. Independent component analyses were performed to generate spatial independent components reflecting functional brain networks or noise. Three radiologists identified the motor components and 3 portions of the motor cortex corresponding to the hand, foot, and face representations. Selected motor independent components were compared with task-based fMRI activation maps resulting from movements of the corresponding body parts. RESULTS: The motor cortex was successfully and consistently identified by using resting-state fMRI by the 3 radiologists for all patients. When they subdivided the motor cortex into 3 segments, the sensitivities of resting-state and task-based fMRI were comparable. Moreover, we report a good spatial correspondence with the task-based fMRI activity estimates. CONCLUSIONS: Resting-state fMRI can reliably image sensorimotor function in a clinical preoperative routine. It is a promising opportunity for presurgical localization of sensorimotor function and has the potential to benefit a large number of patients affected by a wide range of pathologies.

Seizures with tonic posturing: Semiologic difference between supplementary sensorimotor area (SSMA) origin and extra-SSMA origin.

In seizures with tonic posturing, differentiation of seizures originating in SSMA from seizures originating in cortices other than SSMA and spreading to SSMA has not been previously attempted. Twenty-two patients were studied with intractable focal epilepsy with tonic limb posturing as the most prominent semiology, who underwent resective surgery and obtained favorable postoperative seizure outcomes. These 22 patients were divided into an SSMA group (N = 12) and an extra-SSMA group (N = 10), according to the location of resection. Resection area in the extra-SSMA group was located in the dorsolateral frontal or prefrontal area in four patients, the frontal operculum (insula) in two, the parietal cortex in three, and the temporoparietal cortex in one patient. Video-recorded seizures were carefully reviewed. Tonic posturing characteristics and the presence or absence of accompanying symptoms were compared between groups. Incidence of preservation of consciousness was significantly higher in the SSMA group (p < 0.001). Patients in the SSMA group demonstrated a propensity for having unilateral or bilateral asymmetrical tonic limb posturing. In contrast, patients in the extra-SSMA group had a statistically significantly higher incidence of bilateral symmetrical tonic limb posturing (p < 0.05). These findings may be helpful in identifying seizure origin.

Alteration of Regional Homogeneity within the Sensorimotor Network after Spinal Cord Decompression in Cervical Spondylotic Myelopathy: A Resting-State fMRI Study.

There is a lack of longitudinal research to evaluate the function of neurons' adaptive changes within the sensorimotor network (SMN) following recovery after cervical cord decompression. Regional homogeneity (ReHo) may provide information that is critical to fully understand CSM-related functional neural synchrony alterations. The purpose of this study was to assess the ReHo alterations of resting state-functional MRI (rs-fMRI) within pre- and postdecompression CSM and healthy controls (HC) and its correlations with clinical indices. Predecompression CSM demonstrated a significantly lower ReHo in the left primary sensory cortex and primary motor cortex (PostG/PreG) but enhanced ReHo in the right superior parietal lobule (SPL) compared with HC. In comparison with predecompression CSM, the postdecompression CSM showed increased ReHo in the left PostG/PreG but significantly lower ReHo in the right SPL compared with HC patients. Abnormal ReHo regions in pre- or postdecompression CSM showed no significant correlation with the Japanese Orthopaedic Association (JOA) scores, Neck Disability Index (NDI) scores, and disease duration (P > 0.05). This result demonstrated disrupted regional homogeneity within SMN in CSM. This adaptive change in the brain may favor the preservation of sensorimotor networks before and after cervical cord decompression and clinical symptoms independent of ReHo within SMN.

Microsurgical anatomy of the central lobe.

OBJECT: The central lobe consists of the pre- and postcentral gyri on the lateral surface and the paracentral lobule on the medial surface and corresponds to the sensorimotor cortex. The objective of the present study was to define the neural features, craniometric relationships, arterial supply, and venous drainage of the central lobe. METHODS: Cadaveric hemispheres dissected using microsurgical techniques provided the material for this study. RESULTS: The coronal suture is closer to the precentral gyrus and central sulcus at its lower rather than at its upper end, but they are closest at a point near where the superior temporal line crosses the coronal suture. The arterial supply of the lower two-thirds of the lateral surface of the central lobe was from the central, precentral, and anterior parietal branches that arose predominantly from the superior trunk of the middle cerebral artery. The medial surface and the superior third of the lateral surface were supplied by the posterior interior frontal, paracentral, and superior parietal branches of the pericallosal and callosomarginal arteries. The venous drainage of the superior two-thirds of the lateral surface and the central lobe on the medial surface was predominantly through the superior sagittal sinus, and the inferior third of the lateral surface was predominantly through the superficial sylvian veins to the sphenoparietal sinus or the vein of Labbé to the transverse sinus. CONCLUSIONS: The pre- and postcentral gyri and paracentral lobule have a morphological and functional anatomy that differentiates them from the remainder of their respective lobes and are considered by many as a single lobe. An understanding of the anatomical relationships of the central lobe can be useful in preoperative planning and in establishing reliable intraoperative landmarks.

Interhemispheric transfalcine approach and awake cortical mapping for resection of peri-atrial gliomas associated with the central lobule.

Medial posterior frontal and parietal gliomas extending to the peri-atrial region are difficult to reach surgically because of the working angle required to expose the lateral aspect of the tumor and the proximity of the tumor to the sensorimotor lobule; retraction of the sensorimotor cortex may lead to morbidity. The interhemispheric transfalcine approach is favorable and safe for resection of medial hemispheric tumors adjacent to the falx cerebri, but the literature on this approach is scarce. Awake cortical mapping using this operative route for tumors associated with the sensorimotor cortex has not been previously reported to our knowledge. We present the first case of a right medial posterior frontoparietal oligoastrocytoma that was resected through the interhemispheric transfalcine approach using awake cortical and subcortical mapping. Through a contralateral frontoparietal craniotomy, we excised a section of the falx and exposed the contralateral medial hemisphere. Cortical stimulation allowed localization of the supplementary motor cortex, and suprathreshold stimulation mapping excluded the primary motor cortex corresponding to the leg area. Gross total tumor resection was accomplished without any intraoperative or postoperative deficits. Awake cortical mapping using the contralateral transfalcine approach allows a "cross-court" operative route to map functional cortices and resect peri-atrial low-grade gliomas. This technique can minimize the otherwise necessary retraction on the ipsilateral hemisphere through an ipsilateral craniotomy.

Sensorimotor mapping of the human cerebellum during pineal region surgery.

BACKGROUND: The cerebellum is a fundamental structure of the central nervous system. However, in humans, its anatomo-functional organization and the processes through which this organization adapts in response to injuries remain widely unknown. METHODS: Motor and somatosensory evoked potentials were used to map functional representations in the posterior cerebellum of patients with extra- and intracellebellar injuries. Extracerebellar patients had injuries outside the cerebellum (e.g. pineal region, quadrigeminal plate) while intracerebellar patients had injuries within the cerebellum. Data were collected in 20 extracerebellar patients for motor representations. Only preliminary data were gathered for somatosensory representations and intracerebellar patients. RESULTS: In extracerebellar patients, electrical stimulation induced muscle contractions in the ipsilateral hemibody. These representations were somatotopically organized with large overlaps between the face and upper limb in the superior posterior cerebellum and the upper and lower limb in the inferior posterior cerebellum. Neck muscles were represented in the oculomotor vermis. In intracerebellar patients, preliminary data seem to indicate that motor plasticity is achieved by recruiting the contralesional (healthy) cerebellar hemisphere. CONCLUSIONS: Although still ongoing, this project could eventually lead to an improvement of the surgical treatment of patients with lesions of the posterior fossa, by improving our knowledge of cerebellar organization and the process of post-lesional plasticity.

Epilepsy surgery of the rolandic and immediate perirolandic cortex: surgical outcome and prognostic factors.

OBJECTIVE: Herein we present a single-center retrospective study of patients who underwent epilepsy surgery for seizures arising from the sensorimotor (rolandic) cortex. The goal was to find prognostic factors associated with better seizure outcome and to evaluate both surgical and neurologic outcomes. PATIENTS, METHODS, AND MATERIALS: A total of 66 patients fulfilled eligibility criteria and were included in the study. Patients were divided into two groups for analysis: patients with resections within rolandic cortex (RO group; n = 46), and patients with resections in immediate perirolandic cortex and simultaneous sensorimotor multiple subpial transections (IPR group; n = 20). RESULTS: Favorable postoperative seizure outcome (International League Against Epilepsy [ILAE]; ILAE1-ILAE3) was achieved in 42 patients (64%), 39 (59%) of whom were completely seizure-free (ILAE1). The favorable seizure outcome in the RO group (72%) was better than in the IPR group (45%) (p = 0.04, relative risk [RR] 0.51 [0.28-0.94, 95% CI]). Eighteen patients (34%) had a postoperative permanent neurologic deficit. Independent predictors for excellent seizure outcome (ILAE1) after multivariate regression analysis were complete resection of the lesion (p < 0.001), pathology (p = 0.009), age at surgery (p = 0.03), and the absence of preoperative simple partial seizures (p = 0.01). SIGNIFICANCE: With a 64% favorable seizure outcome, surgery for intractable epilepsy arising from sensorimotor cortex is possible and can be worthwhile. The increased risk for postoperative neurologic deficits is higher than in other locations, and this must be discussed with patients in detail prior to surgery. Best postoperative results can be achieved in cases in which a complete resection is possible without damaging eloquent cortical areas.

Combining pyramidal tract mapping, microscopic-based neuronavigation, and intraoperative magnetic resonance imaging improves outcome of epilepsy foci resection in the sensorimotor cortex.

AIM: To explore the clinical value of combining pyramidal tract mapping, microscopic-based neuronavigation, and intraoperative magnetic resonance imaging (iMRI) in the surgical treatment of epileptic foci involving sensorimotor cortex. MATERIAL AND METHODS: We retrospectively analyzed 69 patients with focal epilepsy involving motor and sensory cortex. The surgical operations in Group I (n=38) were performed under the guidance of conventional neuronavigation, and the operations of Group II (n=31) were aided by combining pyramidal tract mapping, microscopic-based neuronavigation and the iMRI technique. Chi square test was used to compare seizure outcome and neurological deficits across groups. RESULTS: 7 patients (18.4%) in Group I, and 3 patients (9.7%) in Group II didn't recover to the level of preoperative strength within one year post-operation. The 2-year follow-up survey showed that more patients in Group II compared to Group I (71% vs. 55.3%, p=0.181) had a good outcome (Engel class I ~ II). CONCLUSION: The techniques of combining pyramidal tract mapping, microscopic-based neuronavigation and iMRI aid in precise mapping and hence resection of epileptic foci in sensorimotor cortex, which lead to improvement of surgical efficacy and significant reduction of postoperative loss of function.