Ricardo Morais

The pCONus device for the endovascular treatment of wide neck bifurcation aneurysms

Background and purpose The pCONus is a new stent featuring a distal end that opens like a blossoming flower with four petals. The device is implanted in the aneurysm sac at the level of the neck. We report our initial experience in a series of patients treated with this device. Methods This retrospective study was approved by the authors’ ethics committees. 18 patients with 19 unruptured wide neck bifurcation intracranial aneurysms (IA) were treated by pCONus placement and coiling. Technical issues, immediate post treatment angiographic findings, and clinical and imaging follow-up were assessed. Results Embolization was successful in all patients. There were 11 women and 7 men with a mean age of 60 years. Median aneurysm size was 9 mm (range 5.5–25 mm). The device was precisely placed and detached in all cases, allowing for subsequent coiling. Two patients experienced a symptomatic complication, one of which, a thromboembolism, was related to the use of the pCONus. This patient had a slight hand paresis. 16 patients had a normal neurological examination at discharge. Immediate anatomical results were 13 complete occlusions, 2 neck remnants, and 4 incomplete occlusions. Imaging follow-up was obtained in 12 patients (mean 9.5 months, range 2–24 months) and showed 9 stable occlusions and 3 recanalizations, of which 2 were retreated. Conclusions In this initial series of patients, endovascular treatment of wide neck bifurcation IAs with the pCONus was feasible, with acceptable clinical and anatomical outcomes. Further studies are needed to evaluate the indications, safety, and efficacy of this new device.

The Silk flow-diverter stent for endovascular treatment of intracranial aneurysms

Flow diverter (FD) stents represent a new endovascular technique developed for the treatment of complex intracranial aneurysms (wide neck, fusiform, large, and giant aneurysms) that are challenging for classic endovascular techniques such as coiling, balloon-assisted coiling and stent-assisted coiling. Low porosity, high metal coverage, and high pore density are the main properties of FD stents. These properties induce hemodynamic changes redirecting the blood flow away from the aneurysm and into the parent artery leading to gradual thrombosis of the aneurysm. FD stents also provide scaffolding for subsequent neoendothelial proliferation, and vessel wall remodeling. This is considered as a paradigm shift compared to prior endovascular methods, which predominantly aimed at providing treatment inside the aneurysmal sac. This paper describes in detail the first released FD stent, the Silk flow-diverter stent (Balt Extrusion, Montmorency, France), its mechanism of action and deployment technique. It reviews the pertinent literature regarding safety, efficacy and potential risks and complications associated with the use of this stent.

The impact of automated hippocampal volumetry on diagnostic confidence in patients with suspected Alzheimer's disease: A European Alzheimer's Disease Consortium study

Hippocampal volume is a core biomarker of Alzheimers disease (AD). However, its contribution over the standard diagnostic workup is unclear.

Three-Dimensional Face Recognition in Mild Cognitive Impairment: A Psychophysical and Structural MR Study.

OBJECTIVES Mild cognitive impairment (MCI) has been associated with a high risk of conversion to Alzheimers dementia. In addition to memory complaints, impairments in the visuospatial domain have been reported in this condition. We have previously shown that deficits in perceiving structure-from-motion (SFM) objects are reflected in functional reorganization of brain activity within the visual ventral stream. Here we aimed to identify structural correlates of psychophysical complex face and object recognition performance in amnestic MCI patients (n=30 vs. n=25 controls). This study was, therefore, motivated by evidence from recent studies showing that a combination of visual information across dorsal and ventral visual streams may be needed for the perception of three-dimensional (3D) SFM objects. METHODS In our experimental paradigm, participants had to discriminate 3D SFM shapes (faces and objects) from 3D SFM meaningless (scrambled) shapes. RESULTS Morphometric analysis established neuroanatomical evidence for impairment in MCI as demonstrated by smaller hippocampal volumes. We found association between cortical thickness and face recognition performance, comprising the occipital lobe and visual ventral stream fusiform regions (overlapping the known location of face fusiform area) in the right hemisphere, in MCI. CONCLUSIONS We conclude that impairment of 3D visual integration exists at the MCI stage involving also the visual ventral stream and contributing to face recognition deficits. The specificity of such observed structure-function correlation for faces suggests a special role of this processing pathway in health and disease. (JINS, 2016, 22, 744-754).

IMPACT OF BIOMARKERS ON DIAGNOSTIC CONFIDENCE IN CLINICAL ASSESSMENT OF PATIENTS WITH SUSPECTED ALZHEIMER'S DISEASE AND HIGH DIAGNOSTIC UNCERTAINTY: AN EADC STUDY

lems with memory and thinking, but tests negative. 95% endorsed being moderately or extremely concerned if a family member had problems with memory and thinking and tests positive, and 25% endorsed being moderately or extremely concerned if a family member does not have any problems with memory and thinking and tests negative. Conclusions: Family members of older adults endorse high levels of concern regarding their family members risk of have Alzheimer’s disease and express willingness to participate in trials measuring the potential benefits and harms of dementia screening on family members of older adults.

Analysis of multiple sclerosis DTI images that uses tract based spatial statistics

Multiple Sclerosis is a demyelinating disease affecting the communication in the central nervous system. Magnetic resonance diffusion imaging provides information about water diffusion in white matter and allows an early detection of abnormalities, comparing to conventional magnetic resonance techniques. The aim of this study is to find out which the brain regions that are damaged during disease progression. Tract-Based Spatial Statistics is a voxelwise multi-subject statistical analysis which performs non-linear registration of each subjects image and projects them onto an alignment-invariant tract representation where the statistical tests are accomplished. This approach improves the sensitivity, objectivity and interpretability of results. The study compares brain images of 64 healthy controls and 59 patients with different stages of Multiple Sclerosis. Some preliminary statistical tests were performed and although the results are still under study, it shows that corticospinal tracts as the most region affected by the disease.