Magnetic Resonance Imaging Brain and Electroencephalogram (EEG) in the Evaluation of New-Onset Seizures in a Tertiary Care Centre of Nepal

Introduction: Seizure is a common neurological condition with multiple etiological factors. This study aims to evaluate the role of magnetic resonance imaging (MRI) Brain and electroencephalography (EEG) in the diagnosis of new-onset seizures in the Nepalese population. Methods: A total of 106 patients aged between 7 to 85 years of age with first onset seizure, who underwent MRI and EEG were enrolled in the study. The sensitivity of MRI and EEG for the diagnosis of seizure when used in combination was compared with that of MRI or EEG alone. Results: Out of 106 patients, 58.5% (n=62) were males and 41.5% (n=44) were females. In 52.8% (n= 56) of the patients, there was epileptogenic lesion in MRI, and 39.6% (n=42) of the patients had an abnormal EEG. The combination of MRI with EEG was significantly better than either MRI or EEG alone in the diagnosis of seizures (p <0.001). Conclusion: MRI and EEG are frequently used for the evaluation of seizures. MRI Brain when used in combination with EEG significantly improves the diagnostic accuracy of seizures.

The role of hybrid FDG-PET/MRI on decision-making in presurgical evaluation of drug-resistant epilepsy

Background When MRI fails to detect a potentially epileptogenic lesion, the chance of a favorable outcome after epilepsy surgery becomes significantly lower (from 60 to 90% to 20–65%). Hybrid FDG-PET/MRI may provide additional information for identifying the epileptogenic zone. We aimed to investigate the possible effect of the introduction of hybrid FDG-PET/MRI into the algorithm of the decision-making in both lesional and non-lesional drug-resistant epileptic patients. Methods In a prospective study of patients suffering from drug-resistant focal epilepsy, 30 nonlesional and 30 lesional cases with discordant presurgical results were evaluated using hybrid FDG-PET/MRI. Results The hybrid imaging revealed morphological lesion in 18 patients and glucose hypometabolism in 29 patients within the nonlesional group. In the MRI positive group, 4 patients were found to be nonlesional, and in 9 patients at least one more epileptogenic lesion was discovered, while in another 17 cases the original lesion was confirmed by means of hybrid FDG-PET/MRI. As to the therapeutic decision-making, these results helped to indicate resective surgery instead of intracranial EEG (iEEG) monitoring in 2 cases, to avoid any further invasive diagnostic procedures in 7 patients, and to refer 21 patients for iEEG in the nonlesional group. Hybrid FDG-PET/MRI has also significantly changed the original therapeutic plans in the lesional group. Prior to the hybrid imaging, a resective surgery was considered in 3 patients, and iEEG was planned in 27 patients. However, 3 patients became eligible for resective surgery, 6 patients proved to be inoperable instead of iEEG, and 18 cases remained candidates for iEEG due to the hybrid FDG-PET/MRI. Two patients remained candidates for resective surgery and one patient became not eligible for any further invasive intervention. Conclusions The results of hybrid FDG-PET/MRI significantly altered the original plans in 19 of 60 cases. The introduction of hybrid FDG-PET/MRI into the presurgical evaluation process had a potential modifying effect on clinical decision-making. Trial registration Trial registry: Scientific Research Ethics Committee of the Medical Research Council of Hungary. Trial registration number: 008899/2016/OTIG. Date of registration: 08 February 2016.

Surgery for Epilepsy Involving Rolandic and Peri-Rolandic Cortex

PurposeTo evaluate the risk factors associated with motor deficit following surgeries involving rolandic & peri-rolandic cortex and to introduce our surgical experiences dealing with lesions in this region.MethodsWe retrospectively reviewed patients who experienced drug-refractory epilepsies and received surgeries in our hospital. Medical records were carefully studied, and patients with lesions located in the rolandic & peri-rolandic cortex were screened. Those with detailed follow-up information were included. Lesion locations, resected regions, and invasive exploration techniques were studied to assess their relationship with the postoperative motor deficit.ResultsA total of 41 patients with lesions located in the rolandic or peri-rolandic cortex were included in this study. Of all these patients, 23 (56.10%) patients suffered from a transient motor deficit and 2 (4.88%) with a permanent disability after surgery. All eight patients with the anterior bank of precentral sulcus resected experienced motor deficit, and six of them gradually recovered within half a year. Seven patients with the anterior half of precentral gyrus resected did not experience permanent disability. A total of 14 (34.15%) patients received invasive exploration, and one of them had a permanent disability.ConclusionsThe anterior bank of the central sulcus is indispensable for motor functions, and the destruction of this region would inevitably cause a motor deficit. The upper part of the central sulcus could also be removed without significant neurological impairment if there is an epileptogenic lesion.

Continuous Intraoperative Neurophysiological Monitoring of the Motor Pathways Using Depth Electrodes During Surgical Resection of an Epileptogenic Lesion: A Novel Technique

BACKGROUND AND IMPORTANCE Intraoperative neurophysiological monitoring of the motor pathways during epilepsy surgery is essential to safely achieve maximal resection of the epileptogenic zone. Motor evoked potential (MEP) recording is usually performed intermittently during resection using a handheld stimulator or continuously through an electrode array placed on the motor cortex. We present a novel variation of continuous MEP acquisition through previously implanted depth electrodes in the perirolandic cortex. CLINICAL PRESENTATION A 60-yr-old woman with a history of a left frontal meningioma (World Health Organization [WHO] grade II) treated with surgical resection and radiation presented with residual right hemiparesis and refractory epilepsy. Imaging demonstrated a perirolandic lesion with surrounding edema and mass effect in the prior surgical site, suspicious for radiation necrosis versus tumor recurrence. Presurgical electrocorticography (ECoG) with orthogonal, stereotactically implanted depth electrodes (stereoelectroencephalography [SEEG]) of the perirolandic cortex captured seizure onsets from the supplementary motor area (SMA) and primary motor cortex (PMC). The patient underwent a left frontal craniotomy for repeat resection and tissue diagnosis. Intraoperative ECoG and MEPs were obtained continuously with direct cortical stimulation through the indwelling SEEG electrodes in the PMC. Maximal resection was achieved with preservation of direct cortical MEPs and without deterioration of her baseline hemiparesis. Biopsy revealed radiation necrosis. At 30-mo follow-up, the patient had only rare seizures (Engel class IIB). CONCLUSION Intraoperative cortical MEP acquisition through implanted SEEG electrode arrays is a potentially safe and effective alternative approach to continuously monitor the motor pathways during the resection of a perirolandic epileptogenic lesion, without the need for surgical interruptions.

Nonconvulsive status epilepticus associated with Alzheimer’s disease mimicking symptomatic focal epilepsy following the resection of a frontal parasagittal meningioma

Background: Epilepsies are frequent in patients with Alzheimer’s disease (AD); however, epilepsies in AD can easily go unrecognized because they usually present as focal impaired awareness seizures or nonconvulsive status epilepticus (NCSE) and can overlap with other symptoms of AD. Case Description: We performed an epilepsy surgery in a 69-year-old woman with progressive cognitive impairment and consciousness disorder, who was diagnosed with focal NCSE related to the resected meningioma in the right frontal parasagittal region. Intraoperative electrocorticography revealed localized periodic paroxysmal discharges with beta and gamma activities in the neighboring cortex where the meningioma existed. The histopathological diagnosis of AD was first made from the resected epileptogenic cortex. Conclusion: Even when there is a suspected epileptogenic lesion that could cause focal NCSE, AD should be ruled out in elderly patients with progressive cognitive decline.

The role of susceptibility-weighted imaging (SWI) in neuroimaging in children with focal epilepsy

Aim. To approve of diagnostic effectiveness of SWAN (SWI) images in revealing of calcium containing epileptogenic substrates in children with resistant focal epilepsy.Materials and methods. The results of MRI in children with refractory focal epilepsy obtained in the Radiology Department of the Russian State Children Hospital in the period from 2018 to 2020 were observed retrospectively. High-resolution epileptological MR protocol used for investigation of 67 children. SWAN was applied in all cases for identification of calcium containing epileptogenic substrates, including cavernomas, DVA syndrome, cortical gangliogliomas, Sturge-Weber syndrome and tuberous sclerosis complex. All images were received by using MRI 3T 750 W Discovery GE.Results. In 17 cases (25%) SWAN provided important diagnostic information about the nature of the of epileptogenic lesion, its prevalence and borders. Additional earlier invisible structural changes were revealed in 2 cases of SWS and 1 cases of FCD; and in 13 cases SWAN gave us possibility to avoid CT for approving calcium in epileptogenic focus.Conclusion. We believe that adding SWAN in to the epileptological MR protocol is the necessary step for optimizing calcium and blood degradation products identification in the structure of potential epileptogenic focuses. Moreover, it would be very effective instrument for differential diagnosis of cerebral structural changes, specifying its etiology and, hence, would have influence on the therapeutic tactic and surgical strategy in children with focal epilepsy.

The Diagnostic Efficacy of MRI Dedicated-Epilepsy Protocol in Evaluation of Seizures

Aims: The aims of this study were to identify the diagnostic efficacy of dedicated epilepsy protocol in detecting possible structural abnormalities that underlie seizure disorders, and compare the diagnostic yields of MRI and electroencephalogram individually and in combination. Study Design: This was a cross-sectional analytic study. Place and Duration of Study: Medical Imaging and Diagnostic Radiology Department at Tishreen University Hospital, Lattakia, Syria; between July 2019 and July 2020. Methodology: Our study included 100 cases (58 females, 41 males, age range 13-77 years) who presented with seizure over 18 months. Patients underwent complete neurological examination, EEG, and MRI with a standard and dedicated epilepsy protocol. Results: We found epileptogenic lesions in MRI in 55.5%. MRI detected epileptogenic lesions in 74.5% patients who had focal onset seizures. Mesial temporal lobe sclerosis was the most common epileptogenic lesion (45.5%). The diagnostic efficacy of MRI had increased with dedicated epilepsy protocol compared to standard protocol. Abnormal MRI and EEG were compatible in 21%. Conclusion: Dedicated epilepsy protocol increased the diagnostic efficacy of brain MRI in detecting a structural epileptogenic lesion, with 100% of mesial temporal sclerosis, the most common lesion in our study, was detected only in dedicated epilepsy protocol and missed in standard protocol.

Prevalence of MRI abnormalities in people with epilepsy in rural China

ObjectiveTo assess the prevalence of brain MRI abnormalities in people with epilepsy in rural China and to compare it with that of individuals in the United Kingdom.MethodsBrain MRI scans were obtained in people with epilepsy who participated in a rural community-based program in China between July 2010 and December 2012. Individual epileptogenic lesion types were reviewed and their associations with seizure control examined. The MRI findings were compared with 2 previous similar studies in the United Kingdom.ResultsAmong the 597 individuals (58% male, median age 38 years) with MRI scans analyzed, 488 (82%) had active epilepsy. The MRI was abnormal in 389 individuals (65%), with potentially epileptogenic lesion in 224 (38%) and nonspecific abnormalities in 165 (28%), and 108 (18%) were potentially resectable. The potentially epileptogenic lesions were less frequently detected in children (<18 years old, 12 of 68, 18%) than in adults (212 of 529, 40%; p < 0.001). In people with potentially epileptogenic lesions, 67% (150 of 224) had failed ≥2 antiseizure medications. They had higher risk of uncontrolled epilepsy than those with normal MRI (risk ratio [RR] 1.25; p < 0.001) and those with nonspecific abnormality (RR 1.15; p = 0.002) after adjustment for age and sex. The diagnostic yield of MRI was similar to that reported in community- and hospital-based studies in the United Kingdom.ConclusionsMore than one-third of people with chronic epilepsy in rural China have potentially epileptogenic lesions identifiable on brain MRI, with two-thirds fulfilling the definition of pharmacoresistance. These findings highlight the magnitude of the unmet needs for epilepsy surgery in China.

Epilepsy, Functional, and Pain Neurosurgery

This chapter covers several aspects of the management of seizures and epilepsy relevant to a general neurosurgical practice. First, all candidates should know how to manage a patient presenting with a new-onset seizure or in status epilepticus with a brain lesion or after a craniotomy. Second, they are expected to be able to explain how to perform fundamental epilepsy procedures such as a temporal lobectomy for hippocampal sclerosis or resection of an epileptogenic lesion. Third, it is useful to have a clear process in place for mapping language and motor function for the resection of tumors located in the eloquent cortex. Lastly, the thought process behind developing an appropriate plan for the surgical management of movement disorders and the technical nuances of managing such cases are discussed. Historically, surgery for pain has been a large part of general neurosurgical practice. A variety of destructive and decompressive interventions have been developed over the years, and a number of comprehensive textbooks have summarized neurosurgical involvement with management of all kinds of medically refractory pain syndromes. It is included in the core neurosurgical education curriculum and is an integral part of neurosurgical knowledge that is tested during the oral board examination. Not surprisingly, cases involving complex pain conditions that require neurosurgical interventions may show up during examinations, and it is expected that examinees are comfortable performing these interventions and able to discuss indications, surgical details, outcomes and complications. Cases include trigeminal neuralgia, cordotomy versus morphine pain pump for cancer pain and a spinal cord stimulator.