Katarina Koprivsek

Current diagnostic trends in radiology

Since the discovery of X-rays by Wilhelm Conrad Röentgen at the end of the 19th century, diagnostic imaging techniques have been continously improved by technological advances, bringing radiological diagnosis into the very center of modern medicine. Nowadays, it is hard to imagine therapy planning without previous radiological examination. Great advances in the field of computer technology have been accompanied by development of radiological techniques, and today they include not only morphological and anatomical, but also dynamic, functional and molecular imaging. This paper is an overview of new and improved radiological techniques and their implementation.

The functional neuroimaging evidence of cerebellar involvement in the simple cognitive task.

Cerebellar involvement in cognitive functions has been revealed in numerous anatomical, clinical and neuroimaging studies and several hypotheses about potential the role of the cerebellum in higher level brain function have been established. The aim of this study was to show involvement of the cerebellum in simple cognitive tasks. For this matter, we contrasted two tasks from the same semantic domain with specific cognitive content and level of practice: counting forward and counting backward. Twelve volunteers participated in this fMRI study and they were asked to perform both tasks within the same number range (1 to 30 and vice versa). Results showed greater activation in the right cerebellum for the task of counting forward than for counting backward, while for counting backward greater activation was found in prefrontal cortex, supplementary motor area, and anterior cingulate of both hemispheres. Our results correlate with already established hypotheses about cerebellar role in precise and smooth control, not only in well-trained motor but in well trained cognitive tasks as well.

Basal ganglia lesions in the early stage of Menkes disease

An 11-month-old boy presented with progressive truncal hypotonia with poor head control and myoclonic seizures. His hair was sparse and stiff, his skin hypopigmented. Magnetic resonance imaging (MRI) (Fig. 1) demonstrated slight volume loss of the supratentorial white matter, symmetrical T2-weighted (T2W) hyperintense signal of the putamens and isolated round lesions of the left caudate head. The basal ganglia lesions showed restricted diffusion on diffusion-weighted imaging (DWI) (Fig. 2). Light microscopy of the boy’s hair demonstrated pili torti. Low levels of plasma copper and caeruloplasmin confirmed the diagnosis of Menkes disease. Menkes disease is an X-linked recessive disorder of metal metabolism, due to a defect in intracellular– intercompartmental copper transport Bindu et al. (2007), Arita et al. (2009). Typical MRI findings are progressive degeneration of grey and white matter, followed by

Multidisciplinary investigation links backward-speech trait and working memory through genetic mutation.

Case studies of unusual traits can provide unique snapshots of the effects of modified systems. In this study, we report on an individual from a Serbian family with the ability to rapidly, accurately and voluntarily speak backwards. We consider psychological, neural and genetic correlates of this trait to identify specific relevant neural mechanisms and new molecular pathways for working memory and speech-related tasks. EEG data suggest that the effect of word reversal precedes semantic integration of visually presented backward-words, and that event-related potentials above the frontal lobe are affected by both word reversal and the maintenance of backward-words in working memory. fMRI revealed that the left fusiform gyrus may facilitate the production of backward-speech. Exome sequencing identified three novel coding variants of potential significance in the RIC3, RIPK1 and ZBED5 genes. Taken together, our data suggest that, in this individual, the ability to speak backwards is afforded by an extraordinary working memory capacity. We hypothesise that this is served by cholinergic projections from the basal forebrain to the frontal cortex and supported by visual semantic loops within the left fusiform gyrus and that these neural processes may be mediated by a genetic mutation in RIC3; a chaperone for nicotinic acetylcholine receptors.

Ictal spitting in left temporal lobe epilepsy and fMRI speech lateralization.

Ictal spitting is a “rare” peri-ictal vegetative sign (PIVS) observed n temporal lobe epilepsy (TLE). Some articles analyzing its lateralzing value have demonstrated that ictal spitting indicates a seizure nset in the non-dominant speech hemisphere [1]. Other studies nd case reports have not shown a lateralizing value for ictal spiting, probably because of low incidence and small sample size [2]. n a recent paper, ictal spitting occurred in 1.03% of patients with LE and 0.26% of seizures arising from the non-dominant temporal obe [3]. We report a man with pharmacoresistent epilepsy who ad a dysembryoplastic neuroepithelial tumor (DNET) in the left emporal lobe and who was considered as a surgical candidate. e recorded his typical seizures. His seizures were accompaied by ictal spitting that might suggest seizure origin from the on-dominant temporal lobe, but the fMRI language lateralization evealed speech activation on the left side.

Dynamic magnetic resonance imaging of the cerebrospinal fluid flow within the cerebral aqueduct by different FISIP 2D sequences

Background/Aim. A vast majority of current radiogical techniques, such as computerized tomography (CT) and magnetic resonance imaging (MRI) have great potential of visualization and delineation of cerebrospinal fluid spaces morphology within cerebral aqueduct. The aim of this study was to determine the possibilities of two differently acquired FISP (Fast Imaging with Steady State Precession) 2D MR sequences in the estimation of the pulsatile cerebrospinal fluid (CSF) flow intensity through the normal cerebral aqueduct. Methods. Sixty eight volunteers underwent brain MRI on 1.5T MR imager with additionally performed ECG retrospectively gated FISP 2D sequences (first one, as the part of the standard software package, with following technical parameters: TR 40, TE 12, FA 17, Matrix: 192 × 256, Acq 1, and the second one, experimentally developed by our investigation team: TR 30, TE 12, FA 70, Matrix: 192 × 256, Acq 1) respectively at two fixed slice positions - midsagittal and perpendicular to cerebral aqueduct, displayed and evaluated by multiplegated images in a closed-loop cinematographic (CINE) format. Results. Normal brain morphology with preserved patency of the cerebral aqueduct in all of 68 healthy volunteers was demonstrated on MRI examination. Cerebrospinal fluid flow within the cerebral aqueduct was distinguishable on both CINE MRI studies in midsagittal plane, but the estimation of intraaqueductal CSF flow in perpendicular plane was possible on CINE MRI studies acquired with experimentally improved FISP 2D (TR 30, FA 70) sequence only. Conclusion. Due to the changes of technical parameters CINE MRI study acquired with FISP 2D (TR 30, FA 70) in perpendicular plane demonstrated significantly higher capability in the estimation of the CSF pulsation intensity within the cerebral aqueduct. .

P30.09: MRI in prenatal diagnosis of fetal hemangioma

Results: TFLV correlated best with FBV, according to the following cubic fit: TFLV = 2E − 09 × FBV3 − 1E − 05 × FBV2 + 0.0508 × FBV − 1.7934 (r2 = 0.85, P < 0.001). The normal median O/E TFLV based on gestational age in eutrophic fetuses (n = 174) was 99.1% (range, 31.2–158.0%) being higher than that in fetuses ≤ 5th percentile (n = 11; 46.2%; range, 15.7–87.3%, P < 0.01) and lower than in fetuses ≥ 95th percentile (n = 15; 146.8%; range, 87.2–204.2%, P < 0.01). However, the normal median O/E TFLV based on FBV was independent of biometric indices irrespective of the percentile of fetal weight. Conclusion: FBV correlated best with TFLV, irrespective of its biometry. In fetuses suspected of pulmonary hypoplasia, the benefit of FBV in prediction of postnatal survival remains to be determined.

fMRI resting state analysis using empirical mode decomposition

The paper studies connectivity pattern between two functionally specialized brain areas: the primary motor area and the occipital (visual) cortex in the resting state fMRI using empirical mode decomposition (EMD). EMD enables identification of low frequency oscillatory modes in the resting state range [0, 01-0, 1 Hz]. Three frequency modes were determined in the resting state band in 13 subjects with the mean frequencies 0,07Hz, 0,034Hz and 0,016Hz. The temporal correlations among the oscillatory modes were strongest within homologous (corresponding) sources in left and right hemisphere, and weakest between the motor-occipital fMRI signal pairs. The functional connectivity - spatial distribution of temporal correlations in the resting state - has been identified and refined by the oscillatory modes. Connectivity graph obtained across all subjects and all IMFs showed high connectivity rate between homologous areas in the left and right hemisphere and among the visual cortex areas. Combining EMD with the Hilbert transformation may provide an additional tool for exploring correlations between frequency and amplitude ridges in task related problems.

FMRI based connectivity analysis of perisylvian language related brain areas

Usually, the focus of fMRI studies is the identification of brain regions that change level of activations as a response to specific stimuli. On the other hand, possible connectivity modeling between activated brain areas remains an open question. Based on fMRI data, in the last decades different methods for uncovering interactions between brain areas have been proposed. In this study we used the generalized Partial Directed Coherence (gPDC) to identify directed interactions between activated brain areas during self paced block fMRI paradigm for the identification of perisylvian language related brain areas.

Ultrasound and magnetic resonance in prenatal diagnosis of congenital anomalies

Publisher Summary Fetal imaging has become standard in prenatal care. Thorough knowledge of not only pathogenesis but also morphological appearances of different anomalies are mandatory for adequate diagnosis. This chapter explains ultrasound and magnetic resonance in prenatal diagnosis of congenital anomalies. Teratogens are agents that cause malformations in a developing embryo. Numerous agents exhibit teratogenic effects. The dose and duration of exposure usually are the main determining factors regarding the severity of the damage and the type of defect. Holoprosencephaly (HPE) is a term used for a group of cerebral anomalies, which are the result of a failure or incomplete cleavage of a primitive forebrain – prosencephalon. Neural tube defects (NTD) and spinal malformations are among the most common congenital malformations. The epidemiology of these anomalies is various – multifactorial inheritance, chromosomal abnormality, teratogens, maternal predisposing factors or they may come as part of a syndrome. Congenital heart disease is a multifactorial disorder and a result of a combined effect of a genetic predisposition and environmental factors in more than 90% of cases. Exomphalos is characterized by herniation of the intra-abdominal contents into the base of the umbilical cord, with a covering amnioperitoneal membrane. The most frequently herniated organs are the liver, bowel and stomach. If abnormalities are found, the parents need as much accurate information as possible in order to make decisions about the future of the pregnancy.