Detection superiority of 7 T MRI protocol in patients with epilepsy and suspected focal cortical dysplasia

In 11 adult patients with suspicion of Focal cortical dysplasia (FCD) on 1.5 T (n = 1) or 3 T (n = 10) magnetic resonance imaging (MRI), 7 T MRI was performed. Visibility, extent, morphological features and delineation were independently rated and subsequently discussed by three observers. Additionally, head-to-head comparisons with corresponding 3 T images were made in the eight patients with a previous 3 T MRI and sustained suspicion of FCD. Comparison with histopathology was done in the five patients that underwent surgery. All lesions, seen at 1.5 and 3 T, were also recognized on 7 T. At 7 T FLAIR highlighted the FCD-like lesions best, whereas T2 and T2* were deemed better suited to review structure and extent of the lesion. Image quality with the used 7 T MRI setup was higher than the quality with the used 3 T MRI setup. In 2 out of 11 patients diagnosis changed, in one after re-evaluation of the images, and in the other based on histopathology. With the used 7 T MRI setup, FCD-like lesions can be detected with more confidence and detail as compared to lower field strength. However, concordance between radiologic diagnosis and final diagnosis seems to be lower than expected

Cerebral Blood Flow in Relation to Contralateral Carotid Disease an MRA and TCD Study

AbstractObjective: to describe redistribution of cerebral blood flow in patients with severe internal carotid artery (ICA) stenoses in relation to contralateral ICA disease. Methods: sixty-six patients scheduled for carotid endarterectomy (CEA) were grouped according to severity of contralateral stenosis (<30% [group I]; 30–69% [group II]; 70–99% [group III]; occlusion [group IV]. Transcranial Doppler (TCD) and magnetic resonance angiography (MRA) investigations were performed preoperatively. Results: TCD demonstrated a reversed flow in the contralateral anterior cerebral artery (A1segment) and ophthalmic artery in three-quarters of group IV patients (p <0.0001). Group IV patients also exhibited decreased blood flow velocity in the contralateral middle cerebral artery (p =0.001). MRA showed increased ipsilateral ICA and basilar artery (BA) blood flow volumes (Q-flows) in group IV patients when compared to the other groups (p <0.001). No changes in total Q-flow (ICAs+BA) were found. Conclusions: in patients considered for CEA, the severity of the contralateral ICA disease is an important determinant of the pattern of blood flow redistribution through the anterior communicating pathway and ophthalmic artery. Significant flow redistribution through the posterior communicating pathway occurs especially in patients with contralateral ICA occlusion

The cinepheur: post-cinematic passage, post-perceptual passage

This thesis develops a hermeneutic commensurate with the aesthetic and ontological challenges of what Steven Shaviro describes as a post-cinematic media ecology, and Shane Denson describes as an emergent post-perceptual media ecology. I consider canonicity and cinephilia as frustrated efforts to contain and comprehend this new cinematic media object, offering a third unit of interpretation in their place, which I describe as the cinetopic anecdote. I associate the cinetopic anecdote with a particular way of moving between cinema and cinematic infrastructure, which I label cinetopic passage, and with a subject position that I label the cinepheur. Drawing on Walter Benjamin’s theory of the flâneur, I argue that the cinetopic anecdote precludes the extraction of a privileged cinematic moment in the manner characteristic of Christian Keathley’s cinephilic anecdote, but instead compels the cinepheur to instantiate, embody or physically recreate the infrastructural conditions that produced it, dovetailing production and consumption into what Axel Bruns has described as the emergent category of produsage; “unfinished artifacts, continuing process.” Having elaborated the cinetopic anecdote, I apply it to postmodern, post-cinematic and post-perceptual media ecologies, in order to evoke the peculiar forms of attachment and obsession bound up with the Criterion and Netflix platforms. In the process, I draw on Franco Moretti’s conception of distant reading to frame the cinetopic anecdote as a unit of distant viewing, offering distant viewings of Angela Christlieb and Stephen Kijak’s Cinemania, Sidney Lumet’s Garbo Talks and Pier Paolo Pasolini’s Salò, or The 120 Days of Sodom. Just as distant reading takes “the great unread” as its object of enquiry, so the cinetopic anecdote speaks to a media ecology preoccupied by the “great unviewed,” in which cinematic scarcity increasingly ramifies as an elegaic object

Loss of integrity and atrophy in cingulate structural covariance networks in Parkinson's disease

Neuro Imaging Researc

Altered Whole-Brain and Network-Based Functional Connectivity in Parkinson's Disease

Neuro Imaging Researc

Stress evokes stronger medial posterior cingulate deactivations during emotional distraction in slower paced aging

Pathophysiology, epidemiology and therapy of agein

The progression of spermatogenesis in the developing rat testis followed by ³¹P MR spectroscopy

To evaluate the use of human testicular 31P MR spectroscopy as a diagnostic tool to differentiate between several stages of male infertility, we have studied the testicular levels of several phosphorus containing compounds in the rat in relation to the condition of spermatogenesis and the cell types present in the seminiferous tubules of the testis. During testicular maturation several characteristic changes occur in the 31P MR spectrum of the testis of male Wistar rats. The phosphomonoester/adenosine triphosphate (PM/ATP) ratio shows a decline from 1.61 to 1.02 between the age of 3 and 12 weeks, whereas the phosphodiester (PD)/ATP ratio increases from 0 to 0.72. The testicular pH increases in the same time from 7.06 to 7.32. Testicular MR data obtained after 12 weeks of age onward do not show significant change anymore. The high PM/ATP ratio is associated by a relative high amount of proliferating spermatogonia and spermatocytes during meiosis in the testis, whereas the PD peak seems to be correlated with the release and maintenance of spermatozoa. The MR spectra show a specific fingerprint in all developmental stages of the rat testis as a result of the different cell types in the testis. © 1992 Academic Press, Inc.</p

Diminished Posterior Precuneus Connectivity with the Default Mode Network Differentiates Normal Aging from Alzheimer's Disease

Multivariate analysis of psychological dat

Association of visit-to-visit variability in blood pressure with cognitive function in old age: prospective cohort study

&lt;p&gt;Objective To investigate the association between visit-to-visit variability in blood pressure and cognitive function in old age (&#62;70 years).&lt;/p&gt; &lt;p&gt;Design Prospective cohort study.&lt;/p&gt; &lt;p&gt;etting PROSPER (PROspective Study of Pravastatin in the Elderly at Risk) study, a collaboration between centres in Ireland, Scotland, and the Netherlands.&lt;/p&gt; &lt;p&gt;Participants 5461 participants, mean age 75.3 years, who were at risk of cardiovascular disease. Blood pressure was measured every three months during an average of 3.2 years. Visit-to-visit variability in blood pressure was defined as the standard deviation of blood pressure measurements between visits.&lt;/p&gt; &lt;p&gt;Main outcome measures Four domains of cognitive function, testing selective attention, processing speed, and immediate and delayed memory. In a magnetic resonance imaging substudy of 553 participants, structural brain volumes, cerebral microbleeds, infarcts, and white matter hyperintensities were measured.&lt;/p&gt; &lt;p&gt;Results Participants with higher visit-to-visit variability in systolic blood pressure had worse performance on all cognitive tests: attention (mean difference high versus low thirds) 3.08 seconds (95% confidence interval 0.85 to 5.31), processing speed −1.16 digits coded (95% confidence interval −1.69 to −0.63), immediate memory −0.27 pictures remembered (95% confidence interval −0.41 to −0.13), and delayed memory −0.30 pictures remembered (95% confidence interval −0.49 to −0.11). Furthermore, higher variability in both systolic and diastolic blood pressure was associated with lower hippocampal volume and cortical infarcts, and higher variability in diastolic blood pressure was associated with cerebral microbleeds (all P&#60;0.05). All associations were adjusted for average blood pressure and cardiovascular risk factors.&lt;/p&gt; Conclusion Higher visit-to-visit variability in blood pressure independent of average blood pressure was associated with impaired cognitive function in old age

Cerebral Perfusion and Aortic Stiffness Are Independent Predictors of White Matter Brain Atrophy in Type 1 Diabetic Patients Assessed With Magnetic Resonance Imaging

OBJECTIVE-To identify vascular mechanisms of brain atrophy in type 1 diabetes mellitus (DM) patients by investigating the relationship between brain volumes and cerebral perfusion and aortic stiffness using magnetic resonance imaging (MRI). RESEARCH DESIGN AND METHODS-Approval from the local institutional review board was obtained, and patients gave informed consent. Fifty-one type 1 DM patients (30 men; mean age 44 +/- 11 years; mean DM duration 23 +/- 12 years) and 34 age- and sex-matched healthy control subjects were prospectively enrolled. Exclusion criteria comprised hypertension, stroke, aortic disease, and standard MRI contraindications. White matter (WM) and gray matter (GM) brain volumes, total cerebral blood flow (tCBF), total brain perfusion, and aortic pulse wave velocity (PWV) were assessed using MRI. Multivariable linear regression analysis was used for statistics, with covariates age, sex, mean arterial pressure, BMI, smoking, heart rate, DM duration, and HbA(1c). RESULTS-Both WM and GM brain volumes were decreased in type 1 DM patients compared with control subjects (WM P = 0.04; respective GM P = 0.03). Total brain perfusion was increased in type 1 DM compared with control subjects (beta = -0.219, P < 0.05). Total CBF and aortic PWV predicted WM brain volume (beta = 0.352, P = 0.024 for tCBF; respective beta = 0.458, P = 0.016 for aortic PWV) in type 1 DM. Age was the independent predictor of GM brain volume (beta = -0.695, P < 0.001). CONCLUSIONS-Type 1 DM patients without hypertension showed WM and GM volume loss compared with control subjects concomitant with a relative increased brain perfusion. Total CBF and stiffness of the aorta independently predicted WM brain atrophy in type 1 DM. Only age predicted GM brain atrophy.Cardiovascular Aspects of Radiolog