Analysis of neuropsychological and neuroradiological features for diagnosis of Alzheimer's disease and mild cognitive impairment.

BACKGROUND: Age-related neurodegenerative diseases are constantly increasing with prediction that in 2050 over 60 % of population will suffer from some level of cognitive impairment. A cure for the Alzheimer's disease (AD) does not exist, so early diagnosis is of a great importance. Machine learning techniques can help in early diagnosis with deep medical data processing, disease understanding, intervention analysis and knowledge discovery for achieving better medical decision making. METHODS: In this paper, we analyze the dataset consisting of 90 individuals and 482 input features. We investigate the achieved AD prediction performances using seven classifiers and five feature selection algorithms. We pay special focus on analyzing performance by utilizing only a subset of best ranked attributes to establish the minimum amount of input features that ensure acceptable performance. We also investigate the significance of neuropsychological (NP) and neuroradiological (NR) attributes for the AD diagnosis. RESULTS: The accuracy for the whole set of attributes ranged between 66.22 % and 81.00 %, and the weighted average AUROC was between 76.3 % and 95.0 %. The best results were achieved by the naive Bayes classifier and the Relief feature selection algorithm. Additionally, Support Vector Machines classifier shows the most stable results since it depends the least on the feature selection algorithm which is used. As the main result of this paper, we compare the performance of models trained with automatically selected features to models trained with hand-selected features performed by medical experts (NP and NR features). CONCLUSIONS: The results reveal that unlike the NR attributes, the NP attributes achieve a good performance that is comparable to the full set of attributes, which suggests that they possess a high predictive power for AD diagnosis.

Serbian Twin Registry.

The first twin study in Serbia began in 2011 as a part of the research project, 'Psychological Foundations of Mental Health: Hereditary and Environmental Factors'. At the same time, the research team from the Faculty of Philosophy and Faculty of Medicine in Novi Sad established the first Serbian twin registry. The registry is intended primarily for the purpose of the research in behavioral genetics, as well as potential future studies in human genetics. It includes information on 1658 volunteers, including twin-pairs, their parent and siblings. The behavioral genetic study of adult twins has been focused on the hereditary and environmental sources of variance of different psychological characteristics, such as personality traits, cognitive abilities, executive functions and aggression, as well as some anthropometric measures and aspects of mental and physical health. Certain molecular genetic analyses have also been performed. The research team is currently starting the longitudinal twin study of children, which will be focused on different indicators of emotional, cognitive and physical development.

Thalamic volume loss as an early sign of amnestic mild cognitive impairment.

The aim of this study was to compare brain volume reduction in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) with age-related changes in age- and gender-matched healthy individuals. Sixty-six patients were divided in three groups based on medical history, neurological and neurocognitive assessment: 26 patients with AD, 20 patients with aMCI and 20 healthy controls. All participants underwent high-resolution magnetic resonance (MR) imaging on 3 T unit. MR volumetry of cerebral cortex, white matter and lateral ventricles volumes, as well as volumes of subcortical nuclei (hippocampus, amygdala, thalamus) was performed. Global cerebral and grey matter volumes were lower in AD patients compared to aMCI (p = 0.023 and p = 0.001, respectively) and controls (p < 0.001 and p < 0.001, respectively). Volume of lateral ventricles was significantly higher in AD patients compared to controls (right p = 0.007, left p = 0.007). Volumes of thalamus were lower in AD patients (right p < 0.001, left p < 0.001), and in aMCI patients (right p = 0.004, left p = 0.015), compared to controls. Hippocampal volume was lower in AD patients compared to both aMCI patients (right p = 0.047, left p = 0.003) and controls (right p < 0.001, left p < 0.001). In aMCI patients, hippocampal volume was lower than in controls (right p = 0.004, left p = 0.007). Volumes of amygdala were lower in AD patients compared to controls (righ p = 0.003, left p = 0.001). Our results show that thalamic volume loss could be an early sign associated with poorercognitiveperformance in aMCI, preceeding the atrophy of amygdala, global grey and white matter volume loss, and cerebrospinal fluid spaces dilatation.

Segmental cavernous carotid ectasia in a patient with cluster-like headache.

INTRODUCTION: Cluster headache (CH) is a primary headache with severe, unilateral periorbital or temporal pain lasting 15-180 min, accompanied with various cranial autonomic features. A diagnosis of cluster-like headache can be made whenever underlying cause of CLH is present. METHODS AND RESULTS: We report a case where an ectatic cavernous segment of the internal carotid artery triggered CHL, most probably due to compression of the ophthalmic nerve within cavernous sinus. The pathological substrate of a vessel ectasia is degeneration of the tunica intima as a consequence of atherosclerosis and hypertension. On the other hand, cavernous sinus is unique space where parasympathetic, sympathetic and nociceptive fibers are in intimate relationship which is of great importance for understanding of CH pathophysiology. CONCLUSION: Magnetic resonance imaging and MR angiography are mandatory imaging tools used for precise localization of pathological changes in the cavernous sinus, especially in the group of secondary headaches attributed to vascular disorders.

Hippocampal diffusion tensor imaging microstructural changes in vascular dementia.

To explore microstructural integrity of hippocampus in vascular dementia (VD) using DTI. Twenty-five individuals with VD, without magnetic resonance imaging (MRI) evidence of gray matter pathology, and 25 matched healthy control (HC) individuals underwent a 3T MRI protocol including T2, FLAIR, and PD in the axial plane, 3D whole-brain T1-weighted with an isotropic resolution of 1 mm, and DTI acquired using 64 diffusion sensitizing directions, b value of 1,500 s/mm(2), 65 axial slices, isotropic resolution of 1.8 mm. Images were processed to obtain indices of microstructural variations of bilateral hippocampi. Mean diffusivity (MD) in the hippocampus of patients with VD was significantly increased (p < 0.05) bilaterally with respect to that of the group of HC examinees. In VD group left hippocampal MD (10(-6 )× mm(2)/s) was 833.4 ± 92.8; in HC group left MD was 699.8 ± 56. In VD group, right hippocampal MD was 859.1 ± 69.8; in HC group right MD was 730.4 ± 40.2. No group differences were found in hippocampal FA. DTI shows microstructural hippocampal damage in VD in patients with normal appearing gray matter structures on conventional MRI, indicating the need for further research on the link between VD and AD.

The effect of post stroke depression on functional outcome and quality of life.

In spite of being a common and important complication of stroke, post stroke depression is often overlooked, so its impact on stroke outcome remains under recognized. The aim of the study was to determine the effect of depression on functional outcome and quality of life in stroke patients. The study included 60 patients treated for their first clinical stroke, 30 of them diagnosed with depression and 30 patients without depression. Testing was done in all patients two and six weeks after stroke. Depression was diagnosed according to the Mini International Neuropsychiatry Interview, DSM-IV diagnostic criteria, and depression severity was quantified by the Hamilton Depression Rating Scale; functional impairment was determined by the Barthel Index; and post stroke quality of life was assessed by the Short Form 36 (SF-36) questionnaires. The patients with depression had significantly more severe functional disability both at baseline and after rehabilitation treatment, although the potential for functional recovery in depressed patients was less than in non-depressed ones. The quality of life in patients with post stroke depression was impaired more severely in all SF-36 domains compared with non-depressed stroke patients, with the domains of the role of emotional functioning and social relations being most severely affected.

Cognitive impairment in multiple system atrophy: a position statement by the Neuropsychology Task Force of the MDS Multiple System Atrophy (MODIMSA) study group.

Consensus diagnostic criteria for multiple system atrophy consider dementia as a nonsupporting feature, despite emerging evidence demonstrating that cognitive impairments are an integral part of the disease. Cognitive disturbances in multiple system atrophy occur across a wide spectrum from mild single domain deficits to impairments in multiple domains and even to frank dementia in some cases. Frontal-executive dysfunction is the most common presentation, while memory and visuospatial functions also may be impaired. Imaging and neuropathological findings support the concept that cognitive impairments in MSA originate from striatofrontal deafferentation, with additional contributions from intrinsic cortical degeneration and cerebellar pathology. Based on a comprehensive evidence-based review, the authors propose future avenues of research that ultimately may lead to diagnostic criteria for cognitive impairment and dementia associated with multiple system atrophy.

Effects of relapsing-remitting multiple sclerosis treatment with interferon beta-1b results of a three-year follow-up study.

The aim of this prospective study was to evaluate therapeutic effects in a cohort of 32 patients with relapsing-remitting multiple sclerosis (RRMS) that were continuously treated with interferon beta-1b during a three-year period and to compare the results obtained with literature data available. Additionally, dropouts and side effects were assessed. The annual relapse rate at three years of treatment as the primary study end-point decreased by 60.5% compared with the relapse rate throughout the pretherapeutic course of disease (0.39 +/- 0.55 vs. 0.97 +/- 0.46; P<0.001) and by 71.3% compared with the relapse rate one year prior to treatment (0.39 +/- 0.55 vs. 1.34 +/- 0.65; P<0.001). The mean Extended Disability Status Scale (EDSS) increased significantly from 2.46 +/- 0.86 at baseline to 2.90 +/- 1.30 (P<0.01) at three years of treatment, whereas the mean progression index (EDSS/disease duration) decreased significantly from 0.76 +/- 0.50 prior to treatment to 0.43 +/- 0.24 (P<0.001), yielding a 56.6% improvement and proving the disease modifying effect of interferon beta-1b. Seventeen (53.12%) patients remained relapse-free during the course of therapy. Among patients that experienced disease relapse, the mean time to first exacerbation was 11.5 +/- 8.34 months. Our study results were consistent with similar studies performed worldwide, clearly indicating that Interferon beta-1b therapy decreased the disease activity and had a beneficial effect on the progression of RRMS, with low incidence and severity of serious side effects. This study has paved way for further long-term follow up studies at our institution.

Nonspecific perichondritis of the lumbar spine.

A teenage girl with soft tissue inflammation involving the L2-S1 region of the lumbar region is reported. Magnetic resonance (MR) imaging revealed high-signal lesions on T2-weighted images in association with contrast enhancement. Histology revealed nonspecific perichondritis with mononuclear inflammatory infiltration of the perichondrium and connective tissue. Six months after treatment, MR imaging was normal. No similar case of perichondritis with involvement of the lumbar region could be found in the current literature.