Reduced long-term mortality after successful resective epilepsy surgery: a population-based study.

BACKGROUND: We investigated all-cause and epilepsy-related mortality in patients operated with resective epilepsy surgery and in non-operated patients with drug-resistant epilepsy. Our hypothesis was that patients who proceed to surgery have lower mortality over time compared with non-operated patients. METHOD: Data from 1329 adults and children from the Swedish National Epilepsy Surgery Register and 666 patients with drug-resistant epilepsy who had undergone presurgical work-up but not been operated were analysed. The operated patients had follow-ups between 2 and 20 years. We used the Swedish Cause of Death Register to identify deaths. Autopsy reports were collected for patients with suspected sudden unexpected death in epilepsy (SUDEP). Kaplan-Meier and Cox regression analyses were performed to identify predictors for mortality and SUDEP. RESULTS: SUDEP accounted for 30% of all deaths. Surgery was associated with lower all-cause mortality (HR 0.7, 95% CI 0.5 to 0.9), also when adjusted for age, sex and tonic-clonic seizures at inclusion. The benefit of surgery seemed to persist and possibly even increase after 15 years of follow-up. Risk factors of mortality for operated patients were persisting seizures and living alone. Of the operated patients, 37% had seizures, and these had a higher risk of mortality (HR 2.1, 95% CI 1.4 to 3.0) and SUDEP (HR 3.5, 95% CI 1.7 to 7.3) compared with patients with seizure freedom at last follow-up. CONCLUSIONS: In this large population-based epilepsy surgery cohort, operated patients had a lower all-cause mortality compared with non-operated patients with drug-resistant epilepsy. Seizure freedom was the most important beneficial factor for both all-cause mortality and SUDEP among operated patients.

Seizure freedom but not epilepsy surgery is associated with fewer neuropsychiatric difficulties in patients with tuberous sclerosis.

BACKGROUND: Drug-resistant epilepsy (DRE) in selected individuals with the rare tuberous sclerosis complex (TSC) may benefit from resective epilepsy surgery. Furthermore, associated neuropsychiatric disorders (TAND) are common in patients with TSC; however, long-term data on how surgery affects neuropsychiatric comorbidities are sparse. MATERIALS AND METHODS: Two retrospective approaches were used to identify children with TSC and DRE with onset at < 18 years of age. The study group (surgical) was identified through the Swedish National Epilepsy Surgery Registry (n = 17), a registry with complete national coverage since 1990 and prospective patient enrolment since 1995. The reference group (non-surgical) was identified by searching medical records retrieved from the tertiary hospital of Southern Sweden (n = 52). Eligible participants were invited to complete the validated TAND lifetime checklist. Those who did not complete the checklist, never had DRE, or were aged < 7 years old were excluded from the study. The reference group was balanced with the study group for putative confounders, in the following hierarchical order: DRE at the survey, age at seizure onset, age at follow-up, and sex. RESULTS: After the balancing procedure, both groups comprised 13 participants. The median time from epilepsy onset to the survey was 18.5 (range: 7.75-40.25) and 16.0 (7.33-33.5) years in the study and reference groups, respectively. The median time from surgery to the survey was 13 years (range: 4-22). No significant differences were found in behavioural problems, autism spectrum disorder diagnosis or symptoms, or intellectual disability between the groups, regardless of surgery. Seizure-free individuals (n = 11) performed better in social skills (p = 0.016), intellectual skills (p = 0.029), and overall TAND scores (p = 0.005) than the non-seizure-free group (n = 15). CONCLUSION: This is the first study to evaluate TAND comorbidities during the long-term follow-up after epilepsy surgery in patients with TSC. We found no evidence of the adverse effects of TAND comorbidities after tuberectomy. However, a larger study that allows for a better adjustment for confounders is needed. Following previous studies, seizure-free individuals had fewer symptoms within most TAND domains compared with the group with uncontrolled epilepsy, indicating less severe symptomatology.

Physicians' attitudes toward generic substitutions of antiseizure drugs in epilepsy.

OBJECTIVES: The safety of generic substitution of antiseizure drugs (ASDs) has been questioned for many years. This study aimed to identify physicians' attitudes to the generic substitution of ASDs in epilepsy and which factors were of significance when deciding on compound substitutions. MATERIAL AND METHODS: A cross-sectional web-based survey was sent to neurologists and neurology residents in public health care and at private practices in two Swedish regions between February and March 2020. The 30-item survey covered drug- and patient-related factors, as well as considerations relating to practical, cost-related, and pharmacokinetic issues. RESULTS: The total response rate was 55.8%. Respondents were generally positive to cutting costs through generic ASD utilization (74%) and prescribing generic compounds when starting a new ASD treatment (84.9%). The most substantial concern was a deterioration in seizure control (17.1%). Physicians refrained from switching if the patient wished to remain on the original compound (76.1%), had a cognitive impairment (52.5%), was on a drug with a narrow therapeutic index (47%), or had shown prior susceptibility to adverse effects (45.6%). Opinions on substitution decisions differed significantly between the Stockholm and Skåne regions. Less than one-third of the respondents were aware of supporting guidelines. CONCLUSIONS: Neurologists generally accept the use of generic antiseizure compounds. Patient preference to remain on brand-name drug treatment was the most important factor that led to avoiding a switch. Our results may constitute material for consensus discussions to decide on quality indicators of interest for future research on substitution outcomes.

Validation of the Swedish version of the Beliefs about Medicines Questionnaire, based on people with epilepsy.

TITLE: Validation of the Swedish version of the Beliefs about Medicines Questionnaire, based on people with epilepsy. PURPOSE: The aims of the study were to explore the latent structure of the Swedish Beliefs about Medicines Questionnaire (BMQ), to investigate its reliability and to identify the extent to which individual factors among people with epilepsy (PWE), as well as their general beliefs about medication, predict their beliefs about their specific anti-seizure drugs (ASDs). METHODS: One-hundred and fifty six included study participants diagnosed with epilepsy and with a well-established neurological follow-up completed an array of rating scales. Included were the Swedish BMQ, which captures beliefs about medicines, scales for symptoms of anxiety and depression and sense of self-efficacy, as well as a general questionnaire regarding their social situation in general. Statistical analysis included Principal Component Analyses (PCA) and hierarchical multiple regression analysis. RESULTS: The PCA revealed a two-factor structure for each of the BMQ-subscales with acceptable (BMQ-G) to high (BMQ-S) internal consistency. The only individual factor that predicted variance in beliefs about medication was patient gender, where levels of both anxiety and depression were elevated in women. CONCLUSION: The Swedish BMQ exhibits psychometric features indicating its reliable use in adult PWE. Our results suggest that the BMQ provides information about the patients' view of their medication regardless of their general mood and that women hold stronger beliefs of concern beyond influence from their levels of depression and anxiety.

Tensor-valued diffusion MRI differentiates cortex and white matter in malformations of cortical development associated with epilepsy.

OBJECTIVE: Delineation of malformations of cortical development (MCD) is central in presurgical evaluation of drug-resistant epilepsy. Delineation using magnetic resonance imaging (MRI) can be ambiguous, however, because the conventional T1 - and T2 -weighted contrasts depend strongly on myelin for differentiation of cortical tissue and white matter. Variations in myelin content within both cortex and white matter may cause MCD findings on MRI to change size, become undetectable, or disagree with histopathology. The novel tensor-valued diffusion MRI (dMRI) technique maps microscopic diffusion anisotropy, which is sensitive to axons rather than myelin. This work investigated whether tensor-valued dMRI may improve differentiation of cortex and white matter in the delineation of MCD. METHODS: Tensor-valued dMRI was performed on a 7 T MRI scanner in 13 MCD patients (age = 32 ± 13 years) featuring periventricular heterotopia, subcortical heterotopia, focal cortical dysplasia, and polymicrogyria. Data analysis yielded maps of microscopic anisotropy that were compared with T1 -weighted and T2 -fluid-attenuated inversion recovery images and with the fractional anisotropy from diffusion tensor imaging. RESULTS: Maps of microscopic anisotropy revealed large white matter-like regions within MCD that were uniformly cortex-like in the conventional MRI contrasts. These regions were seen particularly in the deep white matter parts of subcortical heterotopias and near the gray-white boundaries of focal cortical dysplasias and polymicrogyrias. SIGNIFICANCE: By being sensitive to axons rather than myelin, mapping of microscopic anisotropy may yield a more robust differentiation of cortex and white matter and improve MCD delineation in presurgical evaluation of epilepsy.

Evidence-based anti-seizure monotherapy in newly diagnosed epilepsy: A new approach.

OBJECTIVES: To describe the process and results of the updated Swedish practice guidelines for monotherapy in epilepsy. MATERIALS AND METHODS: The Swedish Medical Products Agency led the process together with medical experts. Evidence rating in accordance with the International League Against Epilepsy (ILAE) template was linked to the Cochrane group's GRADE system. Evidence from recently published trials and meta-analyses was added. A national expert panel participated in the project and contributed their clinical experience. RESULTS: In seizures with focal onset, carbamazepine, lamotrigine, or levetiracetam is recommended for children and adults (ILAE level A-C for adults/Cochrane level strong for children and adults). Oxcarbazepine is an alternative for children, although its level A evidence, in a single class I trial, could relate to poor phenytoin tolerability. Eslicarbazepine acetate, lacosamide, and zonisamide are alternatives for adults and gabapentin for the elderly (ILAE level A). Carbamazepine is not a first choice for the elderly due to its high potential for interactions. In generalized epilepsy with tonic-clonic seizures (GTC), lamotrigine, levetiracetam, and sodium valproate are recommended for children and adults (ILAE level C-D/Cochrane level moderate-strong) although sodium valproate is contraindicated in girls and women of childbearing age unless special considerations are met. Ethosuximide is the first choice in absence epilepsy without GTC (ILAE level A). CONCLUSIONS: Lamotrigine and levetiracetam can be used as first choice for focal seizures and generalized epilepsy with GTC, suitable in all age-groups and for both men and women. Recommendations for GTC seizures have lower evidence than those for focal seizures.

First-line therapy in chronic lymphocytic leukemia: a Swedish nation-wide real-world study on 1053 consecutive patients treated between 2007 and 2013.

The aim of this study was to investigate long-term outcome following first-line therapy in consecutive chronic lymphocytic leukemia (CLL) patients in a well-defined geographic area: Sweden. All patients diagnosed with CLL (2007-2013) (n=3672) were identified from national registries, screening of patient files identified all (100%) treated first line (n=1053) and for those, an in-depth analysis was performed. End points were overall response rate, progression-free survival (PFS), overall survival (OS), and safety. Median age was 71 years; 53% had Rai stage III-IV and 97% had performance status grade 0-2. Fluorescence in situ hybridization (FISH) was performed in 57% of patients: 15% had del(17p). Chlorambucil + prednisone was used in 39% (5% also received rituximab). Fludarabine+cyclophosphamide+rituximab or fludarabine+cyclophosphamide was used in 43% and bendamustine + rituximab in 6%. Overall response rate was 64%; chlorambucil 43%, fludarabine+cyclophosphamide+rituximab 84%, fludarabine+cyclophosphamide 75% and bendamustine + rituximab 75%. Median PFS and OS was 24 and 58 months, respectively, both were significantly associated (multivariate analysis) with type of treatment, del(17p), performance status, gender, age and geographical region (OS only). Chlorambucil-treated patients had a median PFS and OS of only 9 and 33 months, respectively. Chlorambucil usage declined gradually throughout the study period, but one-third of patients still received chlorambucil + rituximab in 2013. Infections ≥grade III were significantly associated with treatment; chlorambucil 19% versus fludarabine+cyclophosphamide+rituximab 30%. Richter transformation occurred in 5.5% of the patients, equally distributed across therapies. This is the largest retrospective, real-world cohort of consecutive first-line treated CLL patients with a complete follow up. In elderly patients, an unmet need for more effective, well-tolerated therapies was identified.

Test-specific differences in verbal memory assessments used prior to surgery in temporal lobe epilepsy.

OBJECTIVE: To study the relationship between two commonly used verbal memory tests in presurgical evaluation for temporal lobe epilepsy (TLE) in Sweden, the Claeson-Dahl Test for verbal learning and retention (CDT) and the Swedish version of the Rey Auditory Verbal Learning Test (RAVLT). METHODS: Fifty-nine patients with TLE (male: 41%, mean: age 41.7 ±â€¯12.3 years; epilepsy onset at mean age: 18.3 ±â€¯13.1 years) previously tested with the CDT, the RAVLT, and three nonverbal memory tests on the same occasion were included. We performed (1) a principal component analysis (PCA) on test performances in the CDT and the RAVLT as well as in nonverbal memory tests; (2) a Pearson's correlation analysis for memory components, biological age, education, age at epilepsy onset, and self-rating scores for depression and anxiety; and (3) an estimation of clinically significant verbal memory impairment in patients with left TLE and left-sided hippocampal sclerosis. RESULTS: The PCAs showed coherence between the learning variables of the CDT and the RAVLT and divergence between the recall variables of the two tests. The RAVLT delayed recall variable was correlated to four out of five nonverbal memory measures. Both tests showed 70-80% clinically significant impairment of verbal memory in patients with left TLE, with or without hippocampal sclerosis, similar to other cohorts with resistant TLE. CONCLUSIONS: The construct structure of the two verbal memory differs. It was shown that the RAVLT correlated with visuospatial memory, whereas the CDT did not. The study highlights that there are important nonoverlapping features regarding verbal recall of the two tests, indicating that these tests cannot fully replace one another.

Verbal memory decline from hippocampal depth electrodes in temporal lobe surgery for epilepsy.

OBJECTIVE: To explore whether patients with refractory mesial temporal lobe epilepsy risk aggravated verbal memory loss from intracranial electroencephalography (EEG) recording with longitudinal hippocampal electrodes in the language-dominant hemisphere. METHODS: A long-term neuropsychological follow-up (mean 61.5 months, range 22-111 months) was performed in 40 patients after ictal registration with left hippocampal depth electrodes (study group, n = 16) or no invasive EEG, only extracranial registration (reference group, n = 24). The groups were equal with respect to education, age at seizure onset, epilepsy duration, and prevalence of pharmacoresistant temporal lobe epilepsy (TLE; 75%) versus seizure freedom (25%). Retrospective neuropsychological data from preoperative surgical workup (T1) and prospective follow-up neuropsychological data (T2) were compared. A ≥1 SD intrapatient decline was considered as clinically relevant deterioration of verbal memory. RESULTS: Significant decline in verbal memory was seen in 56% of the patients in the study group compared to 21% in the reference group. At T1, there were no statistical between-group differences in memory performance. At T2, between-group comparison showed significantly greater verbal memory decline for the study group (Claeson Dahl Learning and Retention Test, Verbal Learning: p = 0.05; Rey Auditory Verbal Learning Test, Total Learning: p = 0.04; Claeson Dahl Learning and Retention Test, Verbal Retention: p = 0.04). An odds ratio (OR) of 7.1 (90% confidence interval [CI] 1.3-37.7) for verbal memory decline was seen if right temporal lobe resection (R TLR) had been performed between T1 and T2. The difference between groups remained unchanged when patients who had undergone R TLR were excluded from the analysis, with a remaining aggravated significant decline in verbal memory performance for the study group compared to the reference group. SIGNIFICANCE: Our results suggest a risk of verbal memory deterioration after the use of depth electrodes along the longitudinal axis of the hippocampus. Until this issue is further investigated, caution regarding depth electrodes in the language-dominant hemisphere hippocampus seems advisable.

A comparative study of fatigue and processing speed in patients with multiple sclerosis treated with natalizumab or rituximab.

Background: Fatigue is the most debilitating symptom in patients with multiple sclerosis (MS). Natalizumab and rituximab are the most used MS disease modifying therapies in Sweden, but comparative data on the effect on fatigue is sparse. Objective: Primary objective was to compare fatigue levels between patients on natalizumab and rituximab. As secondary objective, we assessed processing speed, an attention domain quality, between treatment groups. Method: In this Swedish multicentre cross-sectional study, patients with relapsing-remitting MS and >24 months treatment duration were identified in the Swedish MS-registry. Fatigue was assessed using the Fatigue Scale for Motor and Cognitive functions (FSMC) and processing speed using Symbol Digit Modalities Test (SDMT). Results: 128 patients were enrolled (natalizumab: 56, rituximab: 72). No significant differences in FSMC were found when adjusting for potential confounders (p = 0.936), with age having the biggest impact, correlating with increased fatigue. Individuals on natalizumab performed significantly better on SDMT at cross-section (natalizumab 64.7, rituximab 56.2; p = 0.003), with an improvement from treatment initiation, compared to rituximab (change: natalizumab 8.9, rituximab -1.0; p = 0.002). Conclusion: We found no difference in fatigue levels between natalizumab and rituximab cohorts. Patients treated with natalizumab showed significantly better results on SDMT than patients on rituximab.

Immune response in blood before and after epileptic and psychogenic non-epileptic seizures.

Inflammatory processes may provoke epileptic seizures and seizures may promote an immune reaction. Hence, the systemic immune reaction is a tempting diagnostic and prognostic marker in epilepsy. We explored the immune response before and after epileptic and psychogenic non-epileptic seizures (PNES). Serum samples collected from patients with videoEEG-verified temporal or frontal lobe epilepsy (TLE or FLE) or TLE + PNES showed increased interleukin-6 (IL-6) levels in between seizures (interictally), compared to controls. Patients with PNES had no increase in IL-6. The IL-6 levels increased transiently even further within hours after a seizure (postictally) in TLE but not in FLE patients. The postictal to interictal ratio of additionally five immune factors were also increased in TLE patients only. We conclude that immune factors have the potential to be future biomarkers for epileptic seizures and that the heterogeneity among different epileptic and non-epileptic seizures may be disclosed in peripheral blood sampling independent of co-morbidities.

The evolution of epilepsy surgery in tuberous sclerosis in Sweden: A national registry study.

PURPOSE: This study aimed to characterize the Swedish cohort of surgically treated patients with TSC and explore differences in preoperative investigation and outcome over time. METHODS: Data on patient and seizure characteristics were retrieved from the Swedish National Epilepsy Surgery Register. Two-year follow-up results were compared between the years 1997-2010 and 2011-2018. Preoperative investigations were re-evaluated. RESULTS: Eighteen tuberectomies and seven callosotomies were identified. Seizure freedom after tuberectomy was achieved in 11 % (1/9) 1997-2010 and 56 % (5/9) 2011-2018. The number of tuberectomies increased each decade. Patients operated on in 1997-2010 had higher seizure frequency (median 175 seizures/month vs. 102) and incidence of infantile spasms (4/9 vs. 1/9, none after 2011). There was a trend towards surgery at a younger age (median 86 months 1997-2010 vs. 48 months 2011-2018). None with >200 seizure/month, SEGA, or history of infantile spasms achieved seizure freedom. Two patients underwent anterior callosotomy (1992 and 1994) and became free of drop attacks. Five callosotomies were performed between 2011 and 2013, one patient became free of drop attacks. Two complications with new neurological deficits were reported. The median age at surgery was higher in the callosotomy group (14 years) than in the tuberectomy group (5 years). CONCLUSION: Seizure freedom after tuberectomy in patients with TSC has increased over time in our cohort. Signs of a heavier disease burden were more frequently observed 1997-2010 and associated with worse outcomes. Callosotomy operations were prevalent at the beginning of the 2010s.

Melphalan and prednisone plus thalidomide or placebo in elderly patients with multiple myeloma.

In this double-blind, placebo-controlled study, 363 patients with untreated multiple myeloma were randomized to receive either melphalan-prednisone and thalidomide (MPT) or melphalan-prednisone and placebo (MP). The dose of melphalan was 0.25 mg/kg and prednisone was 100 mg given daily for 4 days every 6 weeks until plateau phase. The dose of thalidomide/placebo was escalated to 400 mg daily until plateau phase and thereafter reduced to 200 mg daily until progression. A total of 357 patients were analyzed. Partial response was 34% and 33%, and very good partial response or better was 23% and 7% in the MPT and MP arms, respectively (P < .001). There was no significant difference in progression-free or overall survival, with median survival being 29 months in the MPT arm and 32 months in the MP arm. Most quality of life outcomes improved equally in both arms, apart from constipation, which was markedly increased in the MPT arm. Constipation, neuropathy, nonneuropathy neurologic toxicity, and skin reactions were significantly more frequent in the MPT arm. The number of thromboembolic events was equal in the 2 treatment arms. In conclusion, MPT had a significant antimyeloma effect, but this did not translate into improved survival. This trial was registered at www.clinicaltrials.gov as #NCT00218855.

Structural association between heterotopia and cortical lesions visualised with 7 T MRI in patients with focal epilepsy.

PURPOSE: To analyze structural characteristics of malformations of cortical development (MCD) at 7T and 3T MRI. METHODS: Twenty-five patients were examined with a 7T MRI-scanner in addition to 3T examinations performed for epilepsy evaluation. 7T sequences included a 3D-T1-weighted (T1w) MPRAGE, 3D-T2w FLAIR, and heavily T2w axial and coronal high-resolution (0.5 × 0.5 × 0.75-1.0 mm3) 2D-TSE sequences. Images were reviewed for 7T MRI imaging characteristics of MCD, visibility and frequency of identified lesions on 7T and on 3T (original reports and second reading). RESULTS: In 25 patients 112 lesions were identified (57 gray matter (GM) heterotopia, 37 focal cortical dysplasia (FCD), and 18 other MCD). Imaging characteristics of the 37 FCD were cortical thickening (n = 11); GM-WM border blurring (n = 30); GM signal intensity changes (n = 18); juxtacortical WM signal intensity changes (n = 18); and transmantle WM signal intensity changes (n = 11). None of the 7T MRI sequences was sufficient to detect all types of lesions. Heterotopia were in general isointense to normal GM. Structural associations between 36 heterotopia and overlaying cortex were observed, composed either of a direct connection, vessel-like structures, or GM-like bridges. FCD were mentioned in 30% (11 of 37) of the original reports at 3T, and in 57% (21 of 37) after second reading. FCD connections to subcortical heterotopia were clinically not reported at all. CONCLUSION: 7T MRI revealed subtle connections between heterotopia and previous unidentified pathology in overlaying cortex. These findings may be significant for the understanding of the anatomical seizure origin and propagation pathways.

Satisfaction and seizure outcomes of epilepsy surgery in tuberous sclerosis: A Swedish population-based long-term follow-up study.

PURPOSE: We conducted a cross-sectional study to evaluate long-term outcomes of epilepsy surgery in tuberous sclerosis complex (TSC) in a Swedish population. METHODS: Demographic and seizure data was retrieved from the Swedish National Epilepsy Surgery Registry and medical records. Patient reported outcome measurements (PROM) were determined by telephonic interviews at long term follow-up. RESULTS: Median follow-up was 6 y 8 m (range, 3-15 y 1 m) for tuberectomies (n = 15) and 3 y 6 m (range 2-10 y) for callosotomies (n = 7). Eight of the 15 tuberectomy participants were seizure-free. Four out of seven callosotomies were free from drop attacks. PROMs were provided by caregivers of 18/20 participants (data missing for two callosotomies). In the tuberectomy group, 6/8 patients were seizure-free and 3/7 had continued seizures; surgery was considered satisfactory and beneficial. Overall, satisfaction was high, even among patients who did not achieve remission; 13/15 tuberectomy responders recommended surgery to others with TSC and refractory epilepsy. None of the patients considered the surgery harmful. In the callosotomy group, satisfaction was low and congruent with the seizure outcome. All patients with continued drop attacks were unsatisfied; one considered surgery to be harmful. One participant, who would not recommend surgery to others, still perceived the surgery to be beneficial. CONCLUSIONS: This study confirmed that both tuberectomy and callosotomy are effective treatment options for TSC. Factors other than seizure outcomes seemed to have a major influence on satisfaction and perception of the benefit of surgery.

Inflammatory reaction in the retina after focal non-convulsive status epilepticus in mice investigated with high resolution magnetic resonance and diffusion tensor imaging.

Pathophysiological consequences of focal non-convulsive status epilepticus (fNCSE) have been difficult to demonstrate in humans. In rats fNCSE pathology has been identified in the eyes. Here we evaluated the use of high-resolution 7 T structural T1-weighted magnetic resonance imaging (MRI) and 9.4 T diffusion tensor imaging (DTI) for detecting hippocampal fNCSE-induced retinal pathology ex vivo in mice. Seven weeks post-fNCSE, increased number of Iba1+ microglia were evident in the retina ipsilateral to the hemisphere with fNCSE, and morphologically more activated microglia were found in both ipsi- and contralateral retina compared to non-stimulated control mice. T1-weighted intensity measurements of the contralateral retina showed a minor increase within the outer nuclear and plexiform layers of the lateral retina. T1-weighted measurements were not performed in the ipsilateral retina due to technical difficulties. DTI fractional anisotropy(FA) values were discretely altered in the lateral part of the ipsilateral retina and unaltered in the contralateral retina. No changes were observed in the distal part of the optic nerve. The sensitivity of both imaging techniques for identifying larger retinal alteration was confirmed ex vivo in retinitis pigmentosa mice where a substantial neurodegeneration of the outer retinal layers is evident. With MR imaging a 50 % decrease in DTI FA values and significantly thinner retina in T1-weighted images were detected. We conclude that retinal pathology after fNCSE in mice is subtle and present bilaterally. High-resolution T1-weighted MRI and DTI independently did not detect the entire pathological retinal changes after fNCSE, but the combination of the two techniques indicated minor patchy structural changes.

7T Epilepsy Task Force Consensus Recommendations on the Use of 7T MRI in Clinical Practice.

Identifying a structural brain lesion on MRI has important implications in epilepsy and is the most important factor that correlates with seizure freedom after surgery in patients with drug-resistant focal onset epilepsy. However, at conventional magnetic field strengths (1.5 and 3T), only approximately 60%-85% of MRI examinations reveal such lesions. Over the last decade, studies have demonstrated the added value of 7T MRI in patients with and without known epileptogenic lesions from 1.5 and/or 3T. However, translation of 7T MRI to clinical practice is still challenging, particularly in centers new to 7T, and there is a need for practical recommendations on targeted use of 7T MRI in the clinical management of patients with epilepsy. The 7T Epilepsy Task Force-an international group representing 21 7T MRI centers with experience from scanning over 2,000 patients with epilepsy-would hereby like to share its experience with the neurology community regarding the appropriate clinical indications, patient selection and preparation, acquisition protocols and setup, technical challenges, and radiologic guidelines for 7T MRI in patients with epilepsy. This article mainly addresses structural imaging; in addition, it presents multiple nonstructural MRI techniques that benefit from 7T and hold promise as future directions in epilepsy. Answering to the increased availability of 7T MRI as an approved tool for diagnostic purposes, this article aims to provide guidance on clinical 7T MRI epilepsy management by giving recommendations on referral, suitable 7T MRI protocols, and image interpretation.

Physical Activity Reduces Epilepsy Incidence: a Retrospective Cohort Study in Swedish Cross-Country Skiers and an Experimental Study in Seizure-Prone Synapsin II Knockout Mice.

BACKGROUND: Epilepsy patients commonly exercise less than the general population. Animal studies indicate beneficial effects of physical activity in established epilepsy, while its effect on the development is currently less known. METHODS: Here, we investigated the incidence of epilepsy during 20 years in a cohort of participants from the long-distance Swedish cross-country ski race Vasaloppet (n = 197,685) and compared it to the incidence of non-participating-matched controls included in the Swedish population register (n = 197,684). Individuals diagnosed with diseases such as stroke and epilepsy before entering the race were excluded from both groups. Experimentally, we also determined how physical activity could affect the development of epilepsy in epilepsy-prone synapsin II knockout mice (SynIIKO), with and without free access to a running wheel. RESULTS: We identified up to 40-50% lower incidence of epilepsy in the Vasaloppet participants of all ages before retirement. A lower incidence of epilepsy in Vasaloppet participants was seen regardless of gender, education and occupation level compared to controls. The participants included both elite and recreational skiers, and in a previous survey, they have reported a higher exercise rate than the general Swedish population. Sub-analyses revealed a significantly lower incidence of epilepsy in participants with a faster compared to slower finishing time. Dividing participants according to specified epilepsy diagnoses revealed 40-50% decrease in focal and unspecified epilepsy, respectively, but no differences in generalized epilepsy. Voluntary exercise in seizure-prone SynIIKO mice for 1 month before predicted epilepsy development decreased seizure manifestation from > 70 to 40%. Brain tissue analyses following 1 month of exercise showed increased hippocampal neurogenesis (DCX-positive cells), while microglial (Iba1) and astrocytic activation (GFAP), neuronal Map2, brain-derived neurotrophic factor and its receptor tyrosine receptor kinase B intensity were unaltered. Continued exercise for additionally 2 months after predicted seizure onset in SynIIKO mice resulted in a 5-fold reduction in seizure manifestation (from 90 to 20%), while 2 months of exercise initiated at the time of predicted seizure development gave no seizure relief, suggesting exercise-induced anti-epileptogenic rather than anti-convulsive effect. CONCLUSION: The clinical study and the experimental findings in mice indicate that physical activity may prevent or delay the development of epilepsy.

Evaluation for epilepsy surgery - Why do patients not proceed to operation?

PURPOSE: To investigate the reasons for not proceeding to surgery in patients undergoing presurgical evaluation for epilepsy. METHODS: A retrospective cohort study of 401 consecutive patients who were evaluated for but did not proceed to surgery for epilepsy between 1990 and 2016 at three Swedish epilepsy surgery centers was performed. Reasons for not proceeding to surgery were categorized as inconclusive investigation, seizure onset within eloquent cortex, evidence of multiple seizure foci, infrequent seizures, risk of postoperative severe cognitive decline, patient or caregiver declining surgery or invasive investigation, severe psychiatric or somatic comorbidity, patient death during evaluation and complications during the evaluation. Chi-square tests were performed to compare ordered categorical variables. RESULTS: During the entire time period the main reasons for rejection were inconclusive investigation (34,4%) and multifocal seizure onset (20,0%). The risk for severe cognitive decline postoperatively was more often a cause for rejection in more recent years. Patients declining invasive EEG or surgery accounted for a minor but not insignificant proportion (14,2%) of rejections. CONCLUSIONS: Inconclusive results from the presurgical evaluation and multifocal epilepsy were the main causes for not proceeding to surgery. The proportion of patients opting to abstain from surgery was low compared to other recent studies.