Evidence of a large current of transcranial alternating current stimulation directly to deep brain regions.

Deep brain regions such as hippocampus, insula, and amygdala are involved in neuropsychiatric disorders, including chronic insomnia and depression. Our recent reports showed that transcranial alternating current stimulation (tACS) with a current of 15 mA and a frequency of 77.5 Hz, delivered through a montage of the forehead and both mastoids was safe and effective in intervening chronic insomnia and depression over 8 weeks. However, there is no physical evidence to support whether a large alternating current of 15 mA in tACS can send electrical currents to deep brain tissue in awake humans. Here, we directly recorded local field potentials (LFPs) in the hippocampus, insula and amygdala at different current strengths (1 to 15 mA) in 11 adult patients with drug-resistant epilepsy implanted with stereoelectroencephalography (SEEG) electrodes who received tACS at 77.5 Hz from 1 mA to 15 mA at 77.5 Hz for five minutes at each current for a total of 40 min. For the current of 15 mA at 77.5 Hz, additional 55 min were applied to add up a total of 60 min. Linear regression analysis revealed that the average LFPs for the remaining contacts on both sides of the hippocampus, insula, and amygdala of each patient were statistically associated with the given currents in each patient (p < 0.05-0.01), except for the left insula of one subject (p = 0.053). Alternating currents greater than 7 mA were required to produce significant differences in LFPs in the three brain regions compared to LFPs at 0 mA (p < 0.05). The differences remained significant after adjusting for multiple comparisons (p < 0.05). Our study provides direct evidence that the specific tACS procedures are capable of delivering electrical currents to deep brain tissues, opening a realistic avenue for modulating or treating neuropsychiatric disorders associated with hippocampus, insula, and amygdala.

Aberrant individual structure covariance network in patients with mesial temporal lobe epilepsy.

Objective: Mesial temporal lobe epilepsy (mTLE) is a complex neurological disorder that has been recognized as a widespread global network disorder. The group-level structural covariance network (SCN) could reveal the structural connectivity disruption of the mTLE but could not reflect the heterogeneity at the individual level. Methods: This study adopted a recently proposed individual structural covariance network (IDSCN) method to clarify the alternated structural covariance connection mode in mTLE and to associate IDSCN features with the clinical manifestations and regional brain atrophy. Results: We found significant IDSCN abnormalities in the ipsilesional hippocampus, ipsilesional precentral gyrus, bilateral caudate, and putamen in mTLE patients than in healthy controls. Moreover, the IDSCNs of these areas were positively correlated with the gray matter atrophy rate. Finally, we identified several connectivities with weak associations with disease duration, frequency, and surgery outcome. Significance: Our research highlights the role of hippo-thalamic-basal-cortical circuits in the pathophysiologic process of disrupted whole-brain morphological covariance networks in mTLE, and builds a bridge between brain-wide covariance network changes and regional brain atrophy.

Delineating structural and metabolic abnormalities in amygdala and hippocampal subfields for different seizure-onset patterns via stereotactic electroencephalography.

AIMS: We aimed to investigate mesial temporal lobe abnormalities in mesial temporal lobe epilepsy (MTLE) patients with hypersynchronous (HYP) and low-voltage fast rhythms (LVF) onset identified by stereotactic electroencephalography (SEEG) and evaluate their diagnostic and prognostic value. METHODS: Fifty-one MTLE patients were categorized as HYP or LVF by SEEG. High-resolution MRI volume-based analysis and 18F-FDG-PET standard uptake values of hippocampal and amygdala subfields were quantified and compared with 57 matched controls. Further analyses were conducted to delineate the distinct pathological characteristics differentiating the two groups. Diagnostic and prognostic prediction performance of these biomarkers were assessed using receiver operating characteristic curves. RESULTS: LVF-onset individuals demonstrated ipsilateral amygdala enlargement (p = 0.048) and contralateral hippocampus hypermetabolism (p = 0.042), pathological results often accompany abnormalities in the temporal lobe cortex, while HYP-onset subjects had significant atrophy (p < 0.001) and hypometabolism (p = 0.013) in ipsilateral hippocampus and its subfields, as well as amygdala atrophy (p < 0.001), pathological results are highly correlated with hippocampal sclerosis. Severe fimbria atrophy was observed in cases of HYP-onset MTLE with poor prognosis (AUC = 0.874). CONCLUSION: Individuals with different seizure-onset patterns display specific morphological and metabolic abnormalities in the amygdala and hippocampus. Identifying these subfield abnormalities can improve diagnostic and prognostic precision, guiding surgical strategies for MTLE.

Misdirection due to early magnetoencephalographic presentation and management in Rasmussen encephalitis: a case report.

Rasmussen encephalitis is a rare and unexplained chronic brain hemispheric inflammatory disease. We report a case of epilepsy in which magnetoencephalography showed dipoles localized only in the operculum. Because the patient's clinical presentation and examination findings did not meet the diagnostic criteria for Rasmussen encephalitis, he underwent cortical electroencephalogram (ECoG) record and limited resection surgery. However, the seizures were not relieved after surgery, and imaging findings showed significant features of hemisphere atrophy. This young male patient was eventually diagnosed with Rasmussen encephalitis and the seizures was completely vanished following hemispherectomy. His data can provide a reference for the early identification of this devastating disease.

Advances in hypothalamic hamartoma research over the past 30 years (1992-2021): a bibliometric analysis.

Background: Hypothalamic hamartoma (HH) is a rare intracranial disease whose manifestations include gelastic seizures and precocious puberty. The diagnosis and treatment of HH have changed substantially over the past three decades as medical care has improved. Bibliometrics can reveal the evolution and development of a scientific field. Methods: Documents on HH were retrieved from the Web of Science Core Collection (WoSCC) database on September 8, 2022. The search terms were as follows: "hypothalamic hamartoma" or "hamartoma of the hypothalamus" or "hypothalamic hamartomas." The types of documents were restricted to articles, case reports, and reviews. VOSviewer, CiteSpace, and the R package "bibliometrix" were used for a bibliometric analysis. Results: A total of 667 independent documents on HH were obtained from the WoSCC database. The most common types of documents were articles (n = 498, 75%) and reviews (n = 103, 15%). The number of annual publications fluctuated but showed an upward trend overall, and the annual growth rate was 6.85%. The cumulative publication data indicated that the most influential journals in the HH field include Epilepsia, Epileptic Disorders, Child's Nervous System, Neurosurgery, and the Journal of Neurosurgery. Kerrigan JF, Ng YT, Rekate HL, Regis J, and Kameyama S were among the most prominent authors in the field of HH, with numerous publications and citations. American research institutions, especially the Barrow Neurological Institute, occupied a pivotal position in HH research. Other countries and institutions were catching up and producing considerable research results. Research on HH has steadily switched its emphasis from Pallister-Hall syndrome (PHS) and precocious puberty to epilepsy and new diagnostic and therapeutic techniques, including Gamma Knife, laser ablation, and interstitial thermal therapy. Conclusion: HH remains a special neurological disease with significant research prospects. The development of novel technologies, including MRI-guided laser-induced thermal therapy (MRg-LiTT) and stereotactic radiofrequency thermocoagulation (RF-TC), has enabled the efficient treatment of gelastic seizures in HH while minimizing the risks associated with craniotomies. Through bibliometric analysis, this study points out the direction for future HH research.

Thyroid function and epilepsy: a two-sample Mendelian randomization study.

Background: Thyroid hormones (THs) play a crucial role in regulating various biological processes, particularly the normal development and functioning of the central nervous system (CNS). Epilepsy is a prevalent neurological disorder with multiple etiologies. Further in-depth research on the role of thyroid hormones in epilepsy is warranted. Methods: Genome-wide association study (GWAS) data for thyroid function and epilepsy were obtained from the ThyroidOmics Consortium and the International League Against Epilepsy (ILAE) Consortium cohort, respectively. A total of five indicators of thyroid function and ten types of epilepsy were included in the analysis. Two-sample Mendelian randomization (MR) analyses were conducted to investigate potential causal relations between thyroid functions and various epilepsies. Multiple testing correction was performed using Bonferroni correction. Heterogeneity was calculated with the Cochran's Q statistic test. Horizontal pleiotropy was evaluated by the MR-Egger regression intercept. The sensitivity was also examined by leave-one-out strategy. Results: The findings indicated the absence of any causal relationship between abnormalities in thyroid hormone and various types of epilepsy. The study analyzed the odds ratio (OR) between thyroid hormones and various types of epilepsy in five scenarios, including free thyroxine (FT4) on focal epilepsy with hippocampal sclerosis (IVW, OR = 0.9838, p = 0.02223), hyperthyroidism on juvenile absence epilepsy (IVW, OR = 0.9952, p = 0.03777), hypothyroidism on focal epilepsy with hippocampal sclerosis (IVW, OR = 1.0075, p = 0.01951), autoimmune thyroid diseases (AITDs) on generalized epilepsy in all documented cases (weighted mode, OR = 1.0846, p = 0.0346) and on childhood absence epilepsy (IVW, OR = 1.0050, p = 0.04555). After Bonferroni correction, none of the above results showed statistically significant differences. Conclusion: This study indicates that there is no causal relationship between thyroid-related disorders and various types of epilepsy. Future research should aim to avoid potential confounding factors that might impact the study.

Long-term outcomes and prognostic factors in patients with treated spinal dural arteriovenous fistulas: a prospective cohort study.

OBJECTIVE: To define the pattern of long-term clinical outcomes and prognostic factors in patients with spinal dural arteriovenous fistulas (SDAVFs). DESGIN: Prospective cohort study based on constantly recruiting patients with SDAVFs in two medical centres in China. SETTING: Patients with SDAVFs were recruited consecutively between March 2013 and December 2014 in two referral centres. PARTICIPANTS: A prospective cohort of 94 patients with SDAVFs was included in this study, and 86 patients (mean age 53.0 years, 71 men) completed the study. Patients who had previously undergone endovascular or neurosurgical treatment or had neurological dysfunction caused by other diseases or refused treatment were excluded. INTERVENTIONS: All patients underwent neurosurgery or endovascular embolisation. These patients were evaluated with the modified Aminoff and Logue's Scale (mALS) 1 day before and 3, 6, 12 and 72 months after treatments. RESULTS: The duration of symptoms ranged from 0.5 to 66 months (average 12.8 months). The location of SDAVFs was as follows: 33.7% above T7, 50.0% between/include T7 and T12% and 16.3% below T12. 75 patients (87.2%) underwent neurosurgical treatment, and 9 patients (10.5%) underwent endovascular treatment. 58 patients (67.4%) exhibited an improvement in mALS of one point or greater at 72 months. Patients with less disability were more likely to improve at 72 months (p<0.05). 48 patients (55.8%) showed deterioration at 72 months compared with 12 months. 61% of the patients suffered numbness, and 22% had pain before treatment. However, 81% of patients had numbness, and 28% had pain after treatment. This deterioration was related to 1-year mALS and age. CONCLUSION: Nearly two-thirds of the patients experienced clinical improvement at 72 months, and preoperative (1 day before treatment) mALS was the strongest predictor of clinical improvement. However, 55.8% of patients showed deterioration after temporary recovery. All patients with SDAVFs should accept treatment as soon as possible.

How can the accuracy of SEEG be increased?-an analysis of the accuracy of multilobe-spanning SEEG electrodes based on a frameless stereotactic robot-assisted system.

BACKGROUND: A frameless stereotactic robot-assisted system allows stereoelectroencephalography (SEEG) electrodes to span multiple lobes. As the angularity and length are increased, maintaining accuracy of the electrodes becomes more challenging. The goal of this study was to analyze the factors that influence the accuracy of multilobe-spanning SEEG electrodes inserted using a frameless stereotactic robot-assisted system. METHODS: A total of 322 SEEG electrodes were implanted in 39 patients with refractory epilepsy, and sixty-one multilobe-spanning SEEG electrodes were selected to analyze the factors that influenced the accuracy of implantation. The target error, entrance error, depth error, and angular error were calculated by a specialized computer program. Factors including electrode depth, angular deviation, referencing method, head holder choice, and use of a predrill procedure were analyzed to determine their effects on accuracy. RESULTS: Thirty-nine patients (aged 2-35 years, median: 19 years; 21 females) underwent frameless robot-assisted SEEG electrode implantation. The mean distance between the intended target and actual tip location was 2.57±1.70 mm (range, 0.42-9.02 mm). The mean distance between the intended entrance point and the actual location was 2.2±1.29 mm (range, 0.70-6.13 mm). The mean length of the electrodes was 84.63±7.61 mm (range, 70.60-103.99 mm). The depth error was 1.36±1.22 mm (range, 0.03-6.69 mm), and the angular deviation was 1.64±1.12 degrees (range, 0.15-4.93 degrees). Multifactor regression analysis showed that entrance error, electrode depth, depth error, angular deviation, referencing method, and head holder choice could explain 59.5% of the electrode target error. Angular deviation, choice of registration approach and head holder and the use of a predrill procedure could explain 48.1% of the electrode entrance error. Use of a predrill procedure significantly reduced the electrode angular deviation (P<0.05). CONCLUSIONS: Head holder choice, use of a predrill procedure and angular deviation are the primary influencing factors of the accuracy of multilobe-spanning SEEG electrode placement. The Leksell frame and a predrill procedure can be used to increase the accuracy of SEEG electrode placement.

Stereotactic EEG-guided radiofrequency thermocoagulation versus anterior temporal lobectomy for mesial temporal lobe epilepsy with hippocampal sclerosis: study protocol for a randomised controlled trial.

INTRODUCTION: In this report, we aim to describe the design for the randomised controlled trial of Stereotactic electroencephalogram (EEG)-guided Radiofrequency Thermocoagulation versus Anterior Temporal Lobectomy for Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis (STARTS). Mesial temporal lobe epilepsy (mTLE) is a classical subtype of temporal lobe epilepsy that often requires surgical intervention. Although anterior temporal lobectomy (ATL) remains the most popular treatment for mTLE, accumulating evidence has indicated that ATL can cause tetartanopia and memory impairments. Stereotactic EEG (SEEG)-guided radiofrequency thermocoagulation (RF-TC) is a non-invasive alternative associated with lower seizure freedom but greater preservation of neurological function. In the present study, we aim to compare the safety and efficacy of SEEG-guided RF-TC and classical ATL in the treatment of mTLE. METHODS AND ANALYSIS: STARTS is a single-centre, two-arm, randomised controlled, parallel-group clinical trial. The study includes patients with typical mTLE over the age of 14 who have drug-resistant seizures for at least 2 years and have been determined via detailed evaluation to be surgical candidates prior to randomisation. The primary outcome measure is the cognitive function at the 1-year follow-up after treatment. Seizure outcomes, visual field abnormalities after surgery, quality of life, ancillary outcomes, and adverse events will also be evaluated at 1-year follow-up as secondary outcomes. DISCUSSION: SEEG-guided RF-TC for mTLE remains a controversial seizure outcome but has the advantage for cognitive and visual field protection. This is the first RCT studying cognitive outcomes and treatment results between SEEG-guided RF-TC and standard ATL for mTLE with hippocampal sclerosis. This study may provide higher levels of clinical evidence for the treatment of mTLE. TRIAL REGISTRATION: ClinicalTrials.gov NCT03941613 . Registered on May 8, 2019. The STARTS protocol has been registered on the US National Institutes of Health. The status of the STARTS was recruiting and the estimated study completion date was December 31, 2021.

Steroid-Associated Acute Clinical Worsening and Poor Outcome in Patients With Spinal Dural Arteriovenous Fistulas: A Prospective Cohort Study.

STUDY DESIGN: A prospective cohort study. OBJECTIVE: We conducted a prospective cohort study to identify the association between steroids and clinical worsening and compare outcomes between patients with and without preoperative steroid administration. SUMMARY OF BACKGROUND DATA: Patients with spinal dural arteriovenous fistulas (SDAVFs) often were misdiagnosed and treated with steroids which led to acute worsening. METHODS: Patients with angiographically confirmed SDAVFs were recruited consecutively between March 2013 and December 2014 in two referral centers. We reviewed the history of all the patients to identify those patients who were treated with steroids before exclusion of the fistulas. Modified Aminoff & Logue scale (mALS) was used to evaluate the spinal cord function at different time points: before and after steroid administration, before operation, and at 1-year follow-up. Paired t tests were used to assess the mALS of patients with steroid administration at different time points. Unpaired t tests and Pearson chi-square test were used to assess differences between patients with and without steroid administration. RESULTS: Eighteen patients with (18.2%) and 81 patients without (81.8%) steroid administration were included in this study. At baseline, there were no difference between both patient groups, in regards to age, sex, duration, location of fistula, treatment, and preoperative mALS. Patients without steroid administration, however, had statistically significant better outcome according to their mALS at 1-year follow-up (P < 0.05). CONCLUSION: Steroid administration can induce acute clinical worsening in patients with SDAVFs that may persist despite successful obliteration of the fistula and should thus be avoided. LEVEL OF EVIDENCE: 3.

Stereo-crossed ablation guided by stereoelectroencephalography for epilepsy: comprehensive coagulations via a network of multi-electrodes.

BACKGROUND: Introducing multiple different stereoelectroencephalography electrodes in a three-dimensional (3D) network to create a 3D-lesioning field or stereo-crossed radiofrequency thermocoagulation (scRF-TC) might create larger lesioning size; however, this has not been quantified to date. This study aimed to quantify the configurations essential for scRF-TC. METHODS: By using polyacrylamide gel (PAG), we investigated the effect of electrode conformation (angled/parallel/multiple edges) and electrode distance of creating an electrode network. Volume, time, and temperature were analyzed quantitatively with magnetic resonance imaging, video analysis, and machine learning. A network of electrodes to the pathological left area 47 was created in a patient; the seizure outcome and coverage range were further observed. RESULTS: After the compatibility test between the PAG and brain tissue, the sufficient distance of contacts (from different electrodes) for confluent lesioning was 7 mm with the PAG. Connection to the lesioning field could be achieved even with a different arrangement of electrodes. One contact could achieve at least six connections with different peripheral contacts. Coagulation with a network of electrodes can create more significant lesioning sizes, 1.81-2.12 times those of the classic approaches. The confluent lesioning field created by scRF-TC had a volume of 38.7 cm3; the low metabolic area was adequately covered. The representative patient was free of seizures throughout the 12-month follow up. CONCLUSION: Lesioning with electrodes in a network manner is practical for adequate 3D coverage. A secondary craniotomy could be potentially prevented by combining both monitoring and a large volume of lesions.

Presurgical Thalamus and Brainstem Shifts Predict Distal Motor Function Recovery After Anatomic Hemispherectomy.

BACKGROUND: Anatomic hemispherectomy is an effective surgical treatment for patients with hemispherical intractable epilepsy. Different degrees of brain shifting have been observed, but whether these shifts can predict motor function recovery is unknown. The aim of this study was to analyze the correlation between brain shift ratios of different brain areas and motor function before and after surgery. METHODS: Medical records and magnetic resonance imaging of 23 patients who underwent anatomic hemispherectomy from 2006 to 2013 at a single center were retrospectively reviewed. Proximal and distal muscle strengths of both arms and legs were measured before and after surgery to determine motor function outcomes. Brain shift ratios of frontal lobe, temporal lobe, parieto-occipital lobe, thalamus, brainstem, and cerebellum were measured before and after surgery to test which shifts could effectively predict motor function outcomes. RESULTS: Fifteen patients (65.2%) showed different degrees of presurgical brain shifting. Brain shift ratios of all measured brain areas were generally increased after anatomic hemispherectomy. After surgery, 13 patients (56.5%) exhibited improved proximal muscle strength, whereas 10 (43.5%) in distal. Significant correlations were found only between muscle strength improvements of distal arms or legs and presurgical brain shift ratios of thalamus or brainstem (all P < 0.05). Distal muscle strength improvements also correlated with age at seizure onset. CONCLUSIONS: Patients with hemispherical intractable epilepsy with larger presurgical shifts of thalamus and brainstem exhibited improved muscle strength, especially in distal muscles, after anatomic hemispherectomy. This result was more likely in patients who were older at the time of seizure onset. These presurgical shifts of thalamus and brainstem may be used for predicting motor function recovery after hemispherectomy for a subset of patients, which is beneficial for surgical planning.

Treatment for patients with recurrent intractable epilepsy after primary hemispherectomy.

BACKGROUND: Hemispherectomy is useful for treating patients with intractable epilepsy caused by diffuse unilateral hemispheric disease. Few patients develop recurrent seizures after hemispherectomy, but managing epilepsy by medical means alone is challenging for these patients, and it is also difficult to determine the treatment options and assess the need for reoperation. OBJECTIVE: To present the treatment strategies and outcomes of patients who developed recurrent intractable epilepsy after initial hemispherectomies that were performed at a single institution by a single surgeon between 2004 and 2014. METHOD: The preoperative medical records, operative reports, imaging findings, and follow-up data for patients with recurrent epilepsy who underwent hemispherectomy for intractable epilepsy between 2004 and 2014 at Sanbo Brain Hospital Capital Medical University were retrospectively reviewed. The baseline characteristics, cause of seizures, imaging findings, electrophysiological findings, primary surgery-related complications, treatments for recurrent epilepsy and long-term seizure outcomes were evaluated. A reduction of seizure frequency greater than 90% was considered a favorable outcome. RESULTS: In the cohort of 17 patients who suffered recurrent epilepsy after primary hemispherectomy, 11 had undergone reoperative surgery, whereas 6 patients took medication alone. No major complications occurred in this series. At the last follow-up, favorable outcome was noted in 10 (91%) patients who underwent reoperative surgery and in 1 (17%) patient who received only medication for treatment (Table 1, p = 0.005). Patients with malformation of cortical development tended to have worse seizure outcomes. CONCLUSIONS: Reoperative hemispherectomy is an effective and safe treatment for patients who still have seizures after primary hemispherectomy for epilepsy caused by unilateral cortical lesion.

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen's Encephalitis.

Rasmussen's encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.

Asymmetry of Cerebral Peduncles for Predicting Motor Function Restoration in Young Patients Before Hemispherectomy.

OBJECTIVE: Hemispherectomy has been used successfully for patients with medically intractable epilepsy. However, it is difficult to predict postoperative motor function. The aim of the present study was to analyze whether the preoperative asymmetry of cerebral peduncles could be used to predict motor function restoration before hemispherectomy for young patients with medically intractable epilepsy. METHODS: The clinical record and magnetic resonance imaging data of 53 patients were analyzed retrospectively. The correlation between preoperative cerebral peduncle asymmetry ratio (pCPAR) and pre- and postoperative changes in motor function was evaluated, as well as the influencing factors for pCPAR, such as duration and etiology factors. The restoration of motor function was defined as changes in pre- and postoperative hemiparesis. RESULTS: The pCPARs of patients with improved and unchanged hemiparesis were significantly greater than that of worsened patients. Patients with a pCPAR of more than 1.5 had an obvious restorative capacity of motor function of the intact hemisphere, and these patients had a lower risk of worsening hemiparesis. The duration in the improved/unchanged and worsened groups was 5.84 ± 3.85 years and 2.67 ± 2.03 years, respectively. Furthermore, there were more patients with no-progressive pathology in the group in whom pCPAR was more than 1.5. CONCLUSIONS: pCPAR is a useful and objective indicator for predicting the restoration of motor function in pediatric patients with medically intractable epilepsy before hemispherectomy. Most patients with nonprogressive pathology and a duration of more than 5 years presented with greater pCPARs, exhibited better restoration of motor function, and had less risk of worsening hemiparesis.

Clinical outcomes and prognostic factors in patients with spinal dural arteriovenous fistulas : a prospective cohort study in two Chinese centres.

BACKGROUND: The short-term outcomes and prognostic factors of patients with spinal dural arteriovenous fistulas (SDAVFs) have not been defined in large cohorts. OBJECTIVE: To define the short-term clinical outcomes and prognostic factors in patients with SDAVFs. METHODS: A prospective cohort of 112 patients with SDAVFs were included consecutively in this study. The patients were serially evaluated with the modified Aminoff and Logue's Scale (mALS) one day before surgery and at 3 months, 6 months and 12 months after treatment. Univariate and multivariate analyses were performed to identify demographic, clinical and procedural factors related to favourable outcome. RESULTS: A total of 94 patients (mean age 53.5 years, 78 were men) met the criteria and are included in the final analyses. Duration of symptom ranged from 0.5 to 66 months (average time period of 12.7 months). The location of SDAVFs was as follows: 31.6% above T7 level, 48.4% between T7 and T12 level (including T7 and T12) and 20.0% below T12 level. A total of 81 patients (86.2%) underwent neurosurgical treatment, 10 patients (10.6%) underwent endovascular treatment, and 3 patients (3.2%) underwent neurosurgical treatment after unsuccessful embolisation. A total of 78 patients demonstrated an improvement in mALS score of one point or greater at 12 months. Preoperative mALS score was associated with clinical improvement after adjusting for age, gender, duration of symptoms, location of fistula and treatment modality using unconditional logistic regression analysis (p<0.05). CONCLUSION: Approximately four fifths of the patients experienced clinical improvement at 12 months and preoperative mALS was the strongest predictor of clinical improvement in the cohort.

Expression of human cytomegalovirus components in the brain tissues of patients with Rasmussen's encephalitis.

Rasmussen's encephalitis (RE) is a rare and severe progressive epileptic syndrome with unknown etiology. Infection by viruses, including human cytomegalovirus (HCMV), has been speculated to be a potential trigger for RE. However, no viral antigens have been detected in the brains of patients with RE; thus, a possible clinical linkage between viral infections and RE has not been firmly established. In this study, we evaluated the expression of HCMV pp65 antigen in brain sections from 26 patients with RE and 20 non-RE patients by immunohistochemistry and in situ hybridization, and assessed the associations between HCMV infection and clinical parameters. Elevated expression of HCMV pp65 protein and DNA was observed in 88.5% (23/26) and 69.2% (18/26) of RE cases, respectively. In the non-RE group, HCMV pp65 antigen was detected only in two cases (10%), both of which were negative for DNA staining. Additionally, the intensity of HCMV pp65 staining was correlated with a shorter duration of the prodromal stage, younger age of seizure onset, and more severe unilateral cortical atrophy. Elevated expression of HCMV pp65 was observed in RE brain tissue and was correlated with the clinical features of RE disease. In summary, our results suggested that HCMV infection may be involved in the occurrence and progression of RE disease. Thus, further studies are needed to determine whether early treatment with anti-HCMV antibodies could modulate the course of RE.

Timing and type of hemispherectomy for Rasmussen's encephalitis: Analysis of 45 patients.

OBJECTIVE: To describe the surgery outcomes of RE patients in one centerto identify the indication for surgical treatment that results in the most favorable outcome. METHOD: Forty-five RE patients from a single center were retrospectively reviewed. Preoperative evaluations included assessments of clinical manifestations, cognitive status, a physical examination, MRI, positron emission tomography (PET), electroencephalography (EEG), and magnetoencephalography (MEG). The surgical outcomes included seizure outcome, neurological function, EEG, a cognitive evaluation, and antiepileptic drug withdrawal. RESULTS: A total of 45 children (29 male) with RE were included in this study. The mean follow-up period from the first operation was 31.7months (range 6-96). The patients who underwent anatomical hemispherectomy or hemisphere disconnection had better seizure outcomes without greater perioperative complications compared with the patients who underwent functional hemispherectomy. Reoperative hemispherectomy was a safe and effective treatment for patients with postoperative epilepsy recurrence. After the last surgery, 34 patients (74.4%) were evaluated as Engel class I. Most of the patients had favorable neurological outcomes. Analysis revealed that the patientswith IQs greater 70 who underwent operations were more likely to suffer from IQ declines but were also more likely to have higher IQs in the future. SIGNIFICANCE: Compared with functional hemispherectomy and hemisphere disconnection, anatomical hemispherectomy elicited better seizure outcomes with an acceptable level of complications. Early stage operations might lead to better cognitive status, but they are associated with a high risk of IQ decline.

Elevated expression of human papillomavirus antigen in brain tissue of patients with Rasmussen's encephalitis.

OBJECTS: To investigate the expression of human papillomavirus (HPV)-specific antigen in the brain tissue of patients with Rasmussen's Encephalitis (RE) and its possible link to the clinical manifestation of RE. METHODS: The correlation between RE and HPV antigen expression in brain tissue sections was investigated using immunohistochemical (IHC) staining, pathological examination, MRI and clinical manifestations. RESULTS: HPV antigen expression was elevated in three out of four patients with RE, whereas there were no detectable HPV antigens in six control patients. Significant staining for HPV antigen was located mainly around or in the nucleus and cytoplasm of neurons. Among these RE patients, three with elevated expression of HPV antigens had obvious hemisphere atrophy, whereas the patient with negative staining for HPV antigens had mild atrophy. CONCLUSIONS: Elevated expression of HPV antigens was observed in the brain tissue of RE patients, which may correlate with hemisphere atrophy. Thus, our results may suggest that HPV infection or being a carrier of HPV may play a role in the initiation and progression of RE.