Diagnostic utility of 3D MRI sequences in the assessment of central, recess and foraminal stenoses of the spine: a systematic review.

OBJECTIVE: To perform a systematic literature review on the diagnostic utility of 3D MRI sequences in the assessment of central canal, recess and foraminal stenosis in the spine. METHODS: The databases PubMed, MEDLINE (via OVID) and The Cochrane Central Register of Controlled Trials, were searched for studies that investigated the diagnostic use of 3D MRI to evaluate stenoses in various parts of the spine in humans. Three reviewers examined the literature and conducted systematic review according to PRISMA 2020 guidelines. RESULTS: Thirty studies were retrieved from 2 595 publications for this systematic review. The overall diagnostic performance of 3D MRI outperformed the conventional 2D MRI with reported sensitivities ranging from 79 to 100% and specificities ranging from 86 to 100% regarding the evaluation of central, recess and foraminal stenoses. In general, high level of agreement (both intra- and interrater) regarding visibility and pathology on 3D sequences was reported. Studies show that well-optimized 3D sequences allow the use of higher spatial resolution, similar scan time and increased SNR and CNR when compared to corresponding 2D sequences. However, the benefit of 3D sequences is in the additional information provided by them and in the possibility to save total protocol scan times. CONCLUSION: The literature on the spine 3D MRI assessment of stenoses is heterogeneous with varying MRI protocols and diagnostic results. However, the 3D sequences offer similar or superior detection of stenoses with high reliability. Especially, the advantage of 3D MRI seems to be the better evaluation of recess stenoses.

Financial impact of incorporating deep learning reconstruction into magnetic resonance imaging routine.

PURPOSE: Artificial intelligence and deep learning solutions are increasingly utilized in healthcare and radiology. The number of studies addressing their enhancement of productivity and monetary impact is, however, still limited. Our hospital has faced a need to enhance MRI scanner throughput, and we investigate the utility of new commercial deep learning reconstruction (DLR) algorithm for this purpose. In this work, a multidisciplinary team evaluated the impact of the widespread deployment of a new commercial deep learning reconstruction (DLR) algorithm for our magnetic resonance imaging scanner fleet. METHODS: Our analysis centers on the DLR algorithm's effects on patient throughput and investment costs, contrasting these with alternative strategies for capacity expansion-namely, acquiring additional MRI scanners and increasing device utilization on weekends. We provide a framework for assessing the financial implications of new technologies in a trial phase, aiding in informed decision-making for healthcare investments. RESULTS: We demonstrate substantial reductions in total operating costs compared to other capacity-enhancing methods. Specifically, the cost of adopting the deep learning technology for our entire scanner fleet is only 11 % compared to procuring an additional scanner and 20 % compared to the weekend utilization costs of existing devices. CONCLUSIONS: Procuring DLR for our existing five-scanner fleet allows us to sustain our current MRI service levels without the need for an additional scanner, thereby achieving considerable cost savings. These reductions highlight the efficiency and economic viability of DLR in optimizing MRI service delivery.

Increased mortality after post-stroke epilepsy following primary intracerebral hemorrhage.

OBJECTIVES: This study aimed to determine whether post-stroke epilepsy (PSE) predicts mortality, and to describe the most prominent causes of death (COD) in a long-term follow-up after primary intracerebral hemorrhage (ICH). METHODS: We followed 3-month survivors of a population-based cohort of primary ICH patients in Northern Ostrobothnia, Finland, for a median of 8.8 years. Mortality and CODs were compared between those who developed PSE and those who did not. PSE was defined according to the ILAE guidelines. CODs were extracted from death certificates (Statistics Finland). RESULTS: Of 961 patients, 611 survived for 3 months. 409 (66.9%) had died by the end of the follow-up. Pneumonia was the only COD that was significantly more common among the patients with PSE (56% vs. 37% of deaths). In the multivariable models, PSE (hazard ratio [HR] 1.41, 95% confidence interval [CI] 1.06-1.87), age (HR 1.07, 95% CI 1.06-1.08), male sex (HR 1.35, 95% CI 1.09-1.67), dependency at 3 months (HR 1.52, 95% CI 1.24-1.88), non-subcortical ICH location (subcortical location HR 0.78, 95% CI 0.61-0.99), diabetes (HR 1.43, 95% CI 1.07-1.90) and cancer (HR 1.45, 95% CI 1.06-1.98) predicted death in the long-term follow-up. CONCLUSION: PSE independently predicted higher late morality of ICH in our cohort. Pneumonia-related deaths were more common among the patients with PSE.

Characterizing Vocal Tract Dimensions in the Vocal Modes Using Magnetic Resonance Imaging.

OBJECTIVE: The aim was to study vocal tract dimensions in four vocal modes - Neutral, Curbing, Overdrive and Edge - from Complete Vocal Technique (CVT) by means of magnetic resonance imaging (MRI). Furthermore, the purpose was to test the feasibility of MRI to assess CVT vocal modes. METHODS: Four nonclassical singers (two females, two males) trained in CVT were imaged with an MRI scanner while singing sustained vowels at same pitch (Bb4 for females, F4 for males) in all vocal modes. Audio signals were simultaneously recorded through a pipe for quality assurance purposes. Auditory evaluation was performed by three CVT teachers in the scanner control room via headphones, and by one CVT teacher inside the MRI room. Previously developed measurement models modified by the authors were used to measure vocal tract dimensions from sagittal MRI projections. Repeatability test was performed for all measurements. RESULTS: In all subjects, vocal tract dimensions displayed differences between the vocal modes. Edge stood out from other vocal modes by showing most laryngeal narrowing accompanied by shortest vocal tract and highest vertical laryngeal position. For Neutral, least mouth opening and shortest distance between tongue and palate were found. Curbing differed consistently from Edge and somewhat from Overdrive showing higher measured values for vocal fold length. Differences regarding vocal fold length were also detected between Neutral and Edge. As expected, differences in vocal tract dimensions were found between samples sung with different vowels. CONCLUSIONS: Vocal tract adjustments play a key role in the production of the vocal modes. The model used to measure vocal tract dimensions succeeded in finding significant differences between the vocal modes, also detecting differences between different vowel productions. The method used to characterize vocal tract dimensions seem promising and would be worthwhile to apply to a larger material.

Correction: Phenotypic spectrum associated with a CRADD founder variant underlying frontotemporal predominant pachygyria in the Finnish population.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Stroke Volume Predicts Nocturnal Hypoxemia in the Acute Ischemic Stroke after Intravenous Thrombolysis.

The Goal: The aim of the study was to investigate whether stroke volume or the presence of ischemic stroke lesion on follow-up computed tomography 1 day after admission had association with sleep apnea among ischemic stroke patients undergoing thrombolysis. MATERIALS AND METHODS: We prospectively recruited 110 consecutive ischemic stroke patients and performed computed tomography on admission and after 24 hours after intravenous thrombolysis. Stroke volume was measured from post-thrombolysis computed tomography scans. Unattended cardiorespiratory polygraphy with a 3-channel device was performed during 48 hours after admission. FINDINGS: Of 110 ischemic stroke patients treated with thrombolysis 65.5% were men. Mean age was 65.8 years and body mass index 27.5 kg/m2. The mean Epworth sleepiness scale score was 4.7. Eight patients (12.7%) with visible acute stroke after thrombolysis and none in the other group had hemorrhage as complication (P ˂ .001). Sleep apnea, determined as a respiratory event index greater than or equal to 5/hour, was diagnosed in 96.4% patients. Respiratory event index greater than 15/h was found in 72.8% of patients. Both mean baseline oxygen desaturation index (23.9 versus 16.5, P = .028) and obstructive apneas/hour (6.2 versus 2.7, P = .007) were higher in visible stroke group. Stroke volume (mean 15.9 mL) correlated with proportion of time spent below saturation less than 90%, P = .025. CONCLUSIONS: Acute ischemic stroke patients treated with thrombolysis with visible stroke were more likely to have nocturnal hypoxemia than patients with not visible strokes. Stroke volume correlated with time spent below saturation of 90%.

Phenotypic spectrum associated with a CRADD founder variant underlying frontotemporal predominant pachygyria in the Finnish population.

Intellectual disability (ID), megalencephaly, frontal predominant pachygyria, and seizures, previously called "thin" lissencephaly, are reported to be caused by recessive variants in CRADD. Among five families of different ethnicities identified, one homozygous missense variant, c.509G>A p.(Arg170His), was of Finnish ancestry. Here we report on the phenotypic variability associated for this potential CRADD founder variant in 22 Finnish individuals. Exome sequencing was used to identify candidate genes in Finnish patients presenting with ID. Targeted Sanger sequencing and restriction enzyme analysis were applied to screen for the c.509G>A CRADD variant in cohorts from Finland. Detailed phenotyping and genealogical studies were performed. Twenty two patients were identified with the c.509G>A p.(Arg170His) homozygous variant in CRADD. The majority of the ancestors originated from Northeastern Finland indicating a founder effect. The hallmark of the disease is frontotemporal predominant pachygyria with mild cortical thickening. All patients show ID of variable severity. Aggressive behavior was found in nearly half of the patients, EEG abnormalities in five patients and megalencephaly in three patients. This study provides detailed data about the phenotypic spectrum of patients with lissencephaly due to a CRADD variant that affects function. High inter- and intrafamilial phenotypic heterogeneity was identified in patients with pachygyria caused by the homozygous CRADD founder variant. The phenotype variability suggests that additional genetic and/or environmental factors play a role in the clinical presentation. Since frontotemporal pachygyria is the hallmark of the disease, brain imaging studies are essential to support the molecular diagnosis for individuals with ID and a CRADD variant.

Poststroke epilepsy in long-term survivors of primary intracerebral hemorrhage.

OBJECTIVE: To identify the incidence and predisposing factors for development of poststroke epilepsy (PSE) after primary intracerebral hemorrhage (PICH) during a long-term follow-up. METHODS: We performed a retrospective study of patients who had had their first-ever PICH between January 1993 and January 2008 in Northern Ostrobothnia, Finland, and who survived for at least 3 months. These patients were followed up for PSE. The associations between PSE occurrence and sex, age, Glasgow Coma Scale (GCS) score on admission, hematoma location and volume, early seizures, and other possible risk factors for PSE were assessed using the Cox proportional hazards regression model. RESULTS: Of the 615 PICH patients who survived for longer than 3 months, 83 (13.5%) developed PSE. The risk of new-onset PSE was highest during the first year after PICH with cumulative incidence of 6.8%. In univariable analysis, the risk factors for PSE were early seizures, subcortical hematoma location, larger hematoma volume, hematoma evacuation, and a lower GCS score on admission, whereas patients with infratentorial hematoma location or hypertension were less likely to develop PSE (all variables p < 0.05). In multivariable analysis, we found subcortical location (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.35-3.81, p < 0.01) and early seizures (HR 3.63, 95% CI 1.99-6.64, p < 0.01) to be independent risk factors, but patients with hypertension had a lower risk of PSE (HR 0.54, 0.35-0.84, p < 0.01). CONCLUSIONS: Subcortical hematoma location and early seizures increased the risk of PSE after PICH in long-term survivors, while hypertension seemed to reduce the risk.

DTI abnormalities in adults with past history of attention deficit hyperactivity disorder: a tract-based spatial statistics study.

BACKGROUND: Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique enabling visualization and measurement of white matter tracts. Attention deficit hyperactivity disorder (ADHD) has been studied with DTI earlier with variable results, yet there is little research on remitted ADHD. PURPOSE: To compare the brain white matter between ADHD drug naïve subjects whose ADHD symptoms have mostly subsided and healthy controls. MATERIAL AND METHODS: Tract-based spatial statistics (TBSS) was used to compare 30 subjects with adolescent ADHD with control subjects at the age of 22-23 years. The study population was derived from a population-based Northern Finland Birth Cohort 1986. Fractional anisotropy (FA), mean diffusivity (MD), and measures of diffusion direction (λ1-3) were calculated. Permutation testing was used to test for differences in mean values of FA, MD, and λ1-3 between the groups. The results were corrected for multiple comparisons across the whole white matter skeleton. RESULTS: The ADHD group showed increased FA related to decreased radial diffusivity in the left forceps minor (P < 0.05). In the vicinity along the same tract, axial diffusion was significantly decreased without any significant effect on FA. No between-group difference in MD was observed. Regressor analysis revealed no gender-, IQ- or GAF-related changes. After removal of left handed subjects the statistical significance was only barely lost. CONCLUSION: In a setting with remitted ADHD, the results may represent a compensatory mechanism in the left forceps minor.

Improved survival of patients with warfarin-associated intracerebral haemorrhage: a retrospective longitudinal population-based study.

BACKGROUND: Warfarin-associated intracerebral haemorrhage carries poor outcome due to rapid haemorrhage growth. Reversal of warfarin anticoagulation with prothrombin complex concentrate has been implemented as an acute treatment option for these subjects. AIM: We investigated whether survival of subjects with warfarin-associated intracerebral haemorrhage had improved after implementation of reversal of warfarin anticoagulation with prothrombin complex concentrate. METHODS: We identified all subjects with warfarin-associated intracerebral haemorrhage during 1993-2008 among the population of Northern Ostrobothnia, Finland. From 2004 onwards, prothrombin complex concentrate was used in Oulu University Hospital, the only hospital treating intracerebral haemorrhage subjects in the region, to counteract the effect of warfarin in subjects with warfarin-associated intracerebral haemorrhage. We compared the outcomes of subjects admitted during 1993-2003 and 2004-2008 and those treated and not treated with prothrombin complex concentrate. We also explored the predictors for one-year survival of the warfarin-associated intracerebral haemorrhage subjects. RESULTS: We identified altogether 181 subjects who had intracerebral haemorrhage while on warfarin. One-year survival was significantly (P = 0·031) higher for the 60 subjects admitted during 2004-2008 (43·3%) than for the 121 admitted before 2004 (30·6%). In multivariable analysis, prothrombin complex concentrate treatment reduced one-year case fatality (hazard ratio 0·52, 95% confidence interval 0·29-0·93). Thromboembolic complications did not occur more frequently among those treated with prothrombin complex concentrate. CONCLUSION: The survival of warfarin-associated intracerebral haemorrhage subjects among the population of Northern Ostrobothnia has improved likely because of introduction of prothrombin complex concentrate.

Predictive value of C-reactive protein for the outcome after primary intracerebral hemorrhage.

OBJECT: Primary intracerebral hemorrhage (ICH) carries high morbidity and mortality rates. Several factors have been suggested as predicting the outcome. The value of C-reactive protein (CRP) levels in predicting a poor outcome is unclear, and findings have been contradictory. In their population-based cohort, the authors tested whether, independent of confounding factors, elevated CRP levels on admission (< 24 hours after ictus) are associated with an unfavorable outcome. METHODS: The authors identified all patients who suffered primary ICH between 1993 and 2008 among the population of Northern Ostrobothnia, Finland, and from the laboratory records they extracted the CRP values at admission. Independent predictors of an unfavorable outcome (moderate disability or worse according to the Glasgow Outcome Scale at 3 months) were tested by unconditional logistic regression in a model including all the well-established confounding factors and CRP on admission. RESULTS: Of 961 patients, 807 (84%) had CRP values available within 24 hours of admission, and multivariable analysis showed elevated CRP at that point to be associated with an unfavorable outcome (OR 1.41 per 10 mg/L [95% CI 1.09-1.81], p < 0.01), together with diabetes mellitus (OR 1.99 [95% CI 1.09-3.64], p < 0.05), age (1.06 per year [95% CI 1.04-1.08], p < 0.001), low Glasgow Coma Scale score (0.75 per unit [95% CI 0.67-0.84], p < 0.001), hematoma size (1.05 per ml [95% CI 1.03-1.07], p < 0.001), and the presence of an intraventricular hemorrhage (2.70 [95% CI 1.66-4.38], p < 0.001). Subcortical location predicted a favorable outcome (0.33 [95% CI 0.20-0.54], p < 0.001). CONCLUSIONS: Elevated CRP on admission is an independent predictor of an unfavorable outcome and is only slightly associated with the clinical and radiological severity of the bleeding.

[Gliomatosis cerebri as cause of neuropsychiatric symptoms]. / Gliomatosis cerebri neuropsykiatristen oireiden syynä.

Gliomatosis cerebri (GC) is a rare cancer of the central nervous system, having already penetrated into various areas of the central nervous system upon becoming manifest. In tissue specimens the histopathologic picture of the tumor appears similar to that seen in diffuse gliomas at different stages of disease. Typical MRI findings in GC include diffuse increases in signal intensity in the brain, and indistinct gray-white matter demarcation in T2-weighted images. Surgical treatment is usually not possible. We describe a patient, in whom CG turned eventually out to be the cause of severe neuropsychiatric symptoms.

Immediate, early and late seizures after primary intracerebral hemorrhage.

BACKGROUND: Seizures after primary intracerebral hemorrhage (PICH) are significant and treatable complications, but the factors predicting immediate, early and late seizures are poorly known. We investigated characteristics and outcome with special reference to occurrence and timing of a first seizure among consecutive subjects with PICH. METHODS: A population-based study was conducted in Northern Ostrobothnia, Finland, in 1993-2008 that included all patients with a first-ever primary ICH without any prior diagnosis of epilepsy. Immediate (<24h after admission), early (1-14 days) and late (>2 weeks) seizures were considered separately. RESULTS: Out of a total of 935 ICH patients, 51 had immediate, 21 early and 58 late seizures. The patients with seizures were significantly younger than the others and more often had a subcortical hematoma location (p<0.05). Lifestyle factors did not differ between the groups. The risk factors for immediate seizures in multivariable analysis were a low Glasgow coma scale score (GCS) on admission, subcortical location and age inversely (p<0.01). The only independent risk factor for early seizures was subcortical location (p<0.001), whereas subcortical location (p<0.001), age inversely (p<0.01) and hematoma evacuation (p<0.05) independently predicted late seizures. Immediate and early seizures predicted infectious complications (p<0.05). CONCLUSIONS: Patients with subcortical hematoma and of younger age are at risk for immediate seizures after primary ICH irrespective of hematoma size. Patients with immediate and early seizures more often had infectious complications. Surgery increases the risk of a late seizure after ICH.

Association between warfarin combined with serotonin-modulating antidepressants and increased case fatality in primary intracerebral hemorrhage: a population-based study.

OBJECT: Patients receiving oral anticoagulants run a higher risk of cerebral hemorrhage with a poor outcome. Serotonin-modulating antidepressants (selective serotonin reuptake inhibitors [SSRIs], serotonin-norepinephrine reuptake inhibitors [SNRIs]) are frequently used in combination with warfarin, but it is unclear whether this combination of drugs influences outcome after primary intracerebral hemorrhage (PICH). The authors investigated case fatality in PICH among patients from a defined population who were receiving warfarin alone, with aspirin, or with serotonin-modulating antidepressants. METHODS: Nine hundred eighty-two subjects with PICH were derived from the population of Northern Ostrobothnia, Finland, for the years 1993-2008, and those with warfarin-associated PICH were eligible for analysis. Their hospital records were reviewed, and medication data were obtained from the national register of prescribed medicines. Kaplan-Meier survival curves were drawn to illustrate cumulative case fatality, and a Cox proportional-hazards analysis was performed to demonstrate predictors of death. RESULTS: Of the 176 patients eligible for analysis, 17 had been taking aspirin and 19 had been taking SSRI/SNRI together with warfarin. The 30-day case fatality rates were 50.7%, 58.8%, and 78.9%, respectively, for those taking warfarin alone, with aspirin, or with SSRI/SNRI (p = 0.033, warfarin plus SSRI/SNRI compared with warfarin alone). Warfarin combined with SSRI/SNRI was a significant independent predictor of case fatality (adjusted HR 2.10, 95% CI 1.13-3.92, p = 0.019). CONCLUSIONS: Concurrent use of warfarin and a serotonin-modulating antidepressant, relative to warfarin alone, seemed to increase the case fatality rate for PICH. This finding should be taken into account if hematoma evacuation is planned.

Clinical Characteristics of C9ORF72-Linked Frontotemporal Lobar Degeneration.

BACKGROUND: The most common genetic cause of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) has been linked to a hexanucleotide repeat expansion in the C9ORF72 gene. The frequency of the C9ORF72 expansion in Finland is among the highest in the world. METHODS: We assessed 73 Finnish patients with FTLD in order to examine the clinical characteristics associated with the expanded C9ORF72. Demographic and clinical features were evaluated. As a potential disease modifier, the apolipoprotein E (APOE) genotype was also assessed. Neuropathological analysis was available on 2 expansion carriers and 1 non-carrier. RESULTS: The C9ORF72 expansion was present in 20 of 70 (29%) probands. Significant associations with the C9ORF72 expansion were observed for concomitant ALS and positive family history of dementia or ALS. Psychoses were detected in both carriers and non-carriers (21 vs. 10%, p = 0.25). The APOE ε4 allele did not cluster among expansion carriers. Numerous p62-positive neuronal inclusions were detected in the cerebellar cortex of the 2 expansion carriers. CONCLUSION: In line with the suggested C9ORF72 core phenotype, we also detected a high frequency of neuropsychiatric symptoms; however, these symptoms seem not be specific to C9ORF72-associated FTLD. FTLD should be considered in cases of middle-age-onset psychosis.

A population based study of outcomes after evacuation of primary supratentorial intracerebral hemorrhage.

BACKGROUND AND PURPOSE: The role of surgery after primary intracerebral hemorrhage (ICH) is controversial. To explore whether hematoma evacuation after ICH had improved short-term survival or functional outcome we conducted a retrospective observational population-based study. METHODS: We identified all subjects with primary ICH between 1993 and 2008 among the population of Northern Ostrobothnia, Finland. Hematoma evacuation was carried out by using standard craniotomy or through a burr hole. We compared mortality rates and functional outcomes of patients with hematoma evacuation with those treated conservatively. RESULTS: Of 982 patients with verified ICH during the study period, 127 (13%) underwent hematoma evacuation. Surgically treated patients were significantly younger (mean±SD, 63±11 vs. 70±12 years; p<0.001), had larger hematomas (66±36 vs. 28±40 ml; p<0.001), lower Glasgow Coma Scale scores (median, 11 vs. 14; p<0.001) and more frequently subcortical hematomas (68% vs. 24%; p<0.001) than those treated conservatively. In multivariable analysis, hematoma evacuation independently lowered 3-month mortality (adjusted hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.43-0.88; p<0.03), particularly among patients aged≤70 years with ≥30 ml supratentorial hematomas (adjusted HR, 0.26; 95% CI, 0.14-0.49; p<0.001). However, poor outcome was not improved by surgery (adjusted odds ratio 0.71; 95% CI 0.29-1.70). CONCLUSIONS: Improved 3-month survival was observed in patients who had undergone hematoma evacuation relative to patients not undergoing evacuation particularly in the subgroup of patients aged≤70 years with ≥30 ml supratentorial hematomas. Surgery might improve outcome if cases could be selected more precisely and if performed before deterioration.

Predictors for recurrent primary intracerebral hemorrhage: a retrospective population-based study.

BACKGROUND AND PURPOSE: Underlying comorbidities, previous strokes, and medication may increase the risk for primary intracerebral hemorrhage (PICH) and its recurrence. The aim of this study was to determine the independent predictors for recurrent PICH. METHODS: We identified 961 subjects with first-ever PICH from 1993 to 2008 among the population of Northern Ostrobothnia, Finland. Hospital and death records were reviewed and data on drug use were obtained from the national register of prescribed medicines. Kaplan-Meier survival curves and Cox proportional hazards models were used to demonstrate predictors for recurrence of PICH. RESULTS: Total follow-up time of the 961 patients was 3481 person-years. During the follow-up time, 58 subjects had altogether 68 recurrent PICHs. The annual average incidence of first recurrence was 1.67%. Cumulative 5- and 10-year incidence rates were 9.6% and 14.2%, respectively. In univariable analysis, history of ischemic stroke, diabetes mellitus, and aspirin use were associated with a higher recurrence rate. In multivariable analysis, only previous ischemic stroke (adjusted hazard ratio, 2.22; 95% confidence interval, 1.22-4.05; P=0.009) independently predicted PICH recurrence. Diabetes mellitus tended to increase (adjusted hazard ratio, 2.38; 95% confidence interval, 0.98-5.80; P=0.056), whereas treated hypertension tended to decrease (0.45, 0.20-1.01; P=0.054) the risk for fatal recurrent PICH. CONCLUSIONS: Previous ischemic stroke independent of confounding factors may increase the risk for PICH recurrence.

White matter in autism spectrum disorders - evidence of impaired fiber formation.

BACKGROUND: Diffusion tensor imaging (DTI) enables measurements and visualization of the microstructure of neural fiber tracts. The existing literature on autism spectrum disorders (ASDs) and DTI is heterogenous both regarding methodology and results. PURPOSE: To compare brain white matter of high-functioning individuals with ASDs and controls. MATERIAL AND METHODS: Tract-based spatial statistics (TBSS), a voxel-based approach to DTI, was used to compare 27 subjects with ASDs (mean age 14.7 years, range 11.4-17.6 years, 20 boys, 7 girls) and 26 control subjects (mean age 14.5 years, range 11.7-17.3 years, 17 boys, 9 girls). Mean fractional anisotropy (FA) image (skeleton) was created and each subject's aligned FA data were then projected onto this skeleton. Voxelwise cross-subject statistics on the skeletonized FA data, mean diffusivity (MD), and measures of diffusion direction were calculated. Importantly, the data were corrected across the whole image instead of using ROI-based methods. RESULTS: The ASD group showed significantly greater FA (P < 0.05, corrected) in the area containing clusters of optic radiation and the right inferior fronto-occipital fasciculus (iFOF). In the same area, λ(3) (representing transverse diffusion) was significantly reduced in the ASD group. No age-related changes were found. CONCLUSION: The results suggest that the reduced transverse diffusion within the iFOF is related to abnormal information flow between the insular salience processing areas and occipital visual areas.

Effect of increased warfarin use on warfarin-related cerebral hemorrhage: a longitudinal population-based study.

BACKGROUND AND PURPOSE: Warfarin use has rapidly increased with the aging of the population. We investigated the temporal trends in the incidence and outcome of warfarin-related intracerebral hemorrhages (ICHs) in a defined population. METHODS: We identified all subjects with first-ever primary ICH during 1993 to 2008 among the population of Northern Ostrobothnia, Finland. The number of warfarin users was obtained from the national register of prescribed medicines kept by the Social Insurance Institution of Finland. We calculated the annual incidence of warfarin-related ICHs, 28-day case fatality, and deaths from the primary bleed. RESULTS: The proportion of warfarin users among the population increased 3.6-fold from 0.68% in 1993 to 2.28% in 2008. Of a total of 982 patients with ICH, 182 (18.5%) had warfarin-related ICH. One-year survival rate after onset of stroke was 35.2% among warfarin users and 67.9% among nonusers. The annual incidence (P=0.062) and 28-day case fatality of warfarin-related ICHs (P=0.002) decreased during the observation period. Warfarin users were older (mean difference 6.6; 95% CI, 5.0 to 8.1; P<0.001) than nonusers. Admission international normalized ratio values above the therapeutic range (2.0 to 3.0) decreased through the observation period, suggesting improved control of anticoagulant therapy over time. CONCLUSIONS: The annual incidence and case fatality of warfarin-related ICHs decreased, although the proportion of warfarin users almost quadrupled in our population.