Structural brain abnormalities in the common epilepsies assessed in a worldwide ENIGMA study.

Progressive functional decline in the epilepsies is largely unexplained. We formed the ENIGMA-Epilepsy consortium to understand factors that influence brain measures in epilepsy, pooling data from 24 research centres in 14 countries across Europe, North and South America, Asia, and Australia. Structural brain measures were extracted from MRI brain scans across 2149 individuals with epilepsy, divided into four epilepsy subgroups including idiopathic generalized epilepsies (n =367), mesial temporal lobe epilepsies with hippocampal sclerosis (MTLE; left, n = 415; right, n = 339), and all other epilepsies in aggregate (n = 1026), and compared to 1727 matched healthy controls. We ranked brain structures in order of greatest differences between patients and controls, by meta-analysing effect sizes across 16 subcortical and 68 cortical brain regions. We also tested effects of duration of disease, age at onset, and age-by-diagnosis interactions on structural measures. We observed widespread patterns of altered subcortical volume and reduced cortical grey matter thickness. Compared to controls, all epilepsy groups showed lower volume in the right thalamus (Cohen's d = -0.24 to -0.73; P < 1.49 × 10-4), and lower thickness in the precentral gyri bilaterally (d = -0.34 to -0.52; P < 4.31 × 10-6). Both MTLE subgroups showed profound volume reduction in the ipsilateral hippocampus (d = -1.73 to -1.91, P < 1.4 × 10-19), and lower thickness in extrahippocampal cortical regions, including the precentral and paracentral gyri, compared to controls (d = -0.36 to -0.52; P < 1.49 × 10-4). Thickness differences of the ipsilateral temporopolar, parahippocampal, entorhinal, and fusiform gyri, contralateral pars triangularis, and bilateral precuneus, superior frontal and caudal middle frontal gyri were observed in left, but not right, MTLE (d = -0.29 to -0.54; P < 1.49 × 10-4). Contrastingly, thickness differences of the ipsilateral pars opercularis, and contralateral transverse temporal gyrus, were observed in right, but not left, MTLE (d = -0.27 to -0.51; P < 1.49 × 10-4). Lower subcortical volume and cortical thickness associated with a longer duration of epilepsy in the all-epilepsies, all-other-epilepsies, and right MTLE groups (beta, b < -0.0018; P < 1.49 × 10-4). In the largest neuroimaging study of epilepsy to date, we provide information on the common epilepsies that could not be realistically acquired in any other way. Our study provides a robust ranking of brain measures that can be further targeted for study in genetic and neuropathological studies. This worldwide initiative identifies patterns of shared grey matter reduction across epilepsy syndromes, and distinctive abnormalities between epilepsy syndromes, which inform our understanding of epilepsy as a network disorder, and indicate that certain epilepsy syndromes involve more widespread structural compromise than previously assumed.

Risk of Shunting After Aneurysmal Subarachnoid Hemorrhage: A Collaborative Study and Initiation of a Consortium.

BACKGROUND AND PURPOSE: Shunt dependent hydrocephalus after aneurysmal subarachnoid hemorrhage (aSAH) is a common sequela that may lead to poor neurological outcome and predisposes to various interventions, admissions, and complications. We reviewed post-aSAH shunt dependency in a population-based sample and tested the feasibility of a clinical risk score to identify subgroups of aSAH patients with increasing risk of shunting for hydrocephalus. METHODS: A total of 1533 aSAH patients from the population-based Eastern Finland Saccular Intracranial Aneurysm Database (Kuopio, Finland) were used in a recursive partitioning analysis to identify risk factors for shunting after aSAH. The risk model was built and internally validated in random split cohorts. External validation was conducted on 946 aSAH patients from the Southwestern Tertiary Aneurysm Registry (Dallas, TX) and tested using receiver-operating characteristic curves. RESULTS: Of all patients alive ≥14 days, 17.7% required permanent cerebrospinal fluid diversion. The recursive partitioning analysis defined 6 groups with successively increased risk for shunting. These groups also successively risk stratified functional outcome at 12 months, shunt complications, and time-to-shunt rates. The area under the curve-receiver-operating characteristic curve for the exploratory sample and internal validation sample was 0.82 and 0.78, respectively, with an external validation of 0.68. CONCLUSIONS: Shunt dependency after aSAH is associated with higher morbidity and mortality, and prediction modeling of shunt dependency is feasible with clinically useful yields. It is important to identify and understand the factors that increase risk for shunting and to eliminate or mitigate the reversible factors. The aSAH-PARAS Consortium (Aneurysmal Subarachnoid Hemorrhage Patients' Risk Assessment for Shunting) has been initiated to pool the collective insights and resources to address key questions in post-aSAH shunt dependency to inform future aSAH treatment guidelines.

Increased incidence of aneurysmal subarachnoid hemorrhage on Sundays and Mondays in 1,862 patients from Eastern Finland.

BACKGROUND: Temporal patterns of aneurysmal subarachnoid hemorrhage (aSAH) from saccular intracranial aneurysm (sIA) were studied in a consecutive series of 1,862 patients. METHODS: Neurosurgery of Kuopio University Hospital (KUH) solely serves a defined catchment population in Eastern Finland. Kuopio's sIA database contains 1,596 sporadic and 266 familial patients admitted to KUH within 72 h from the onset of aSAH between 1980 and 2007. The distributions by the weekday of the onset of aSAH, admission to KUH, and occlusive therapy of the ruptured sIA were analyzed. Logistic regression was used to search for clinical variables (patients, sIA disease, clinical condition) that would independently correlate with each distribution. RESULTS: The onset of aSAH occurred significantly most often (p < 0.001) on Sundays (n = 330) and Mondays (n = 309) and least frequently on Saturdays (n = 231). None of the clinical variables tested associated significantly and independently with the Sunday and Monday peaks. The admissions to KUH after aSAH were most frequent (p < 0.001) on Mondays (n = 331) and least frequent on Thursdays (n = 221) and Saturdays (n = 221). Overall, 1,655 patients underwent occlusive therapy, most frequently on Mondays (n = 318) and least frequently on Saturdays (n = 189) and Sundays (n = 197). CONCLUSIONS: Sundays and Mondays were the most frequent and Saturdays the least frequent days of aSAH in a defined Eastern Finnish population. We could not identify any etiology to this temporal pattern. Binge drinking is frequent in Finland, especially among young males, but age and gender did not correlate with the Sunday and Monday peaks.

Detecting pathological features and predicting fracture risk from dual-energy X-ray absorptiometry images using deep learning.

Dual-energy X-ray absorptiometry (DXA) is the gold standard imaging method for diagnosing osteoporosis in clinical practice. The DXA images are commonly used to estimate a numerical value for bone mineral density (BMD), which decreases in osteoporosis. Low BMD is a known risk factor for osteoporotic fractures. In this study, we used deep learning to identify lumbar scoliosis and structural abnormalities that potentially affect BMD but are often neglected in lumbar spine DXA analysis. In addition, we tested the approach's ability to predict fractures using only DXA images. A dataset of 2949 images gathered by Kuopio Osteoporosis Risk Factor and Prevention Study was used to train a convolutional neural network (CNN) for classification. The model was able to classify scoliosis with an AUC of 0.96 and structural abnormalities causing unreliable BMD measurement with an AUC of 0.91. It predicted fractures occurring within 5 years from the lumbar spine DXA scan with an AUC of 0.63, meeting the predictive performance of combined BMD measurements from the lumbar spine and hip. In an independent test set of 574 clinical patients, AUC for lumbar scoliosis was 0.93 and AUC for unreliable BMD measurements was 0.94. In each classification task, neural network visualizations indicated the model's predictive strategy. We conclude that deep learning could complement the well established DXA method for osteoporosis diagnostics by analyzing incidental findings and image reliability, and improve its predictive ability in the future.

Temporal anteroinferior encephalocele: An underrecognized etiology of temporal lobe epilepsy?

OBJECTIVE: To report the increasing frequency with which temporal anteroinferior encephalocele is a cause of adult temporal lobe epilepsy, to illustrate the clinical and imaging characteristics of this condition, and to report its surgical treatment in a series of 23 adult patients. METHODS: Epilepsy patients diagnosed with temporal anteroinferior encephalocele from January 2006 to December 2013 in a national epilepsy reference center were included in this noninterventional study. RESULTS: Twenty-three epilepsy patients (14 female, mean age 43.8 years) were diagnosed with temporal anteroinferior encephalocele in our institute. Thirteen patients had ≥2 encephaloceles; 7 cases presented bilaterally. The estimated frequency of this condition was 0.3% among MRI examinations performed due to newly diagnosed epilepsy (n = 6) and 1.9% among drug-resistant patients referred to our center (n = 17). Nine patients with local encephalocele disconnection (n = 4) or anterior temporal lobectomy and amygdalohippocampectomy (n = 5) have become seizure-free (Engel 1) for a mean 2.8 years (range 3 months-6.2 years) of follow-up. Three patients with local encephalocele disconnection were almost seizure-free or exhibited worthwhile improvement. Histologically, all 12 surgical patients had gliosis at the base of the encephalocele; some had cortical laminar disorganization (n = 5) or mild hippocampal degeneration (n = 1). CONCLUSIONS: The possibility of a temporal encephalocele should be considered when interpreting MRI examinations of patients with medically intractable focal epilepsy. These patients can significantly benefit from unitemporal epilepsy surgery, even in cases with bilateral encephaloceles.