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Morphological assessment using Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) is still the workhorse of tumor detection and diagnosis. In particular, MRI provides detailed information about cerebral tumor anatomy, cellular metabolism and hemodynamic features, making it a fundamental tool for a correct diagnosis, treatment and monitoring of the disease. Various new functional imaging modalities assessing tissue microstructure and physiology have increased the scope of neuro imagingdoi:10.4236/jbise.2013.63a051 fatcat:yrgo3ve75bfpfnu723lpbi7rda
more »... and raised expectations among clinicians. This article provides an overview of the most advanced MR imaging techniques (functional MRI, perfusion-weighted imaging, diffusion-weighted imaging and MR spectroscopy) now available for neurosurgical planning and their role in brain tumors assessment. Their pros and cons are analyzed in order to find out which one may be chosen as best diagnostic pre-surgical protocol. At the moment none of the single techniques can be considered the golden standard; only the integration of advanced and conventional MR imaging proves to be a reliable tool in the hands of the neuroradiologist and neurosurgeon, thus maximazing tumor resection and function preservation.
Awake surgery requires coordinated teamwork and communication between the surgeon and the anesthesiologist, as he monitors the patient, the neuroradiologist as he interprets the images for intraoperative confirmation, and the neuropsychologist and neurophysiologist as they evaluate in real-time the patient's responses to commands and questions. To improve comparison across published studies on clinical assessment and operative settings in awake surgery, we reviewed the literature, focusing ondoi:10.11138/fneur/2013.28.3.205 pmid:24139657 pmcid:PMC3812739 fatcat:nhcpdbvtr5bpbmxivjrqyc7x6u
more »... thodological differences and aims. In complex, interdisciplinary medical care, such differences can affect the outcome and the cost-benefit ratio of the treatment. Standardization of intraoperative mapping and related controversies will be discussed in Part II.
Hypothalamic abnormalities in schizophrenia have been associated with endocrine dysfunctions and stress response. The hypothalamus is involved in several pathways found disrupted in schizophrenia (e.g. hypothalamic-pituitary-adrenal axis, HPA axis); however the available results on potential structural hypothalamic alterations are still controversial. The aim of the study was to investigate the volumes of the hypothalamus and the mammillary bodies in patients with schizophrenia and healthydoi:10.1016/j.pscychresns.2012.10.006 pmid:23217575 fatcat:uftjio4qtbd3zaa5g33bmgfbeu
more »... ols. Twenty-six patients with schizophrenia and 26 healthy controls underwent a 3 Tesla magnetic resonance imaging (MRI) scan. Hypothalamus and mammillary bodies were manually traced by a rater who was blind to subjects' identity. The General Linear Model was used in group comparisons of the volumes of the hypothalamus and the mammillary bodies. The hypothalamus and mammillary body volumes were significantly larger in patients with schizophrenia than controls, with significant enlargement of the left hypothalamus and trends for significantly increased right hypothalamus and right mammillary body. The size of the mammillary bodies was inversely correlated with negative symptoms and directly correlated with anxiety. This study showed abnormally increased sizes of the hypothalamus and the mammillary bodies in schizophrenia. Mammillary bodies volumes were associated to negative symptoms and anxiety. Future longitudinal studies on the volumes of the hypothalamus and the mammillary bodies with respect to the levels of related hormones will clarify their role in modulating HPA axis in schizophrenia.
Advances in the Biology, Imaging and Therapies for Glioblastoma
Productivity of old-growth beech forests in the Mediterranean Basin was measured by average stem basal area increment (BAI) of dominant trees at two mountain sites in the Italian Apennines. Both forests could be ascribed to the old-growth stage, but they differed markedly with regard to elevation (1000 vs. 1725 m a.s.l.), soil parent material (volcanic vs. calcareous), mean tree age (less than 200 years vs. 300 years), and stand structure (secondary old-growth vs. primary old-growth forest).doi:10.1111/j.1365-2486.2008.01570.x fatcat:p2q2uophfferlkciapfbb35yy4
more »... ught at the two sites was quantified by the self-calibrated Palmer Moisture Anomaly Index (Z-index), and by the self-calibrating Palmer Drought Severity Index (PDSI) for summer (June through August) and the growing season (May through September). Dendroclimatological analyses revealed a moisture limitation of beech BAI at interannual (water availability measured by Z-index) and decadal scales (water availability measured by PDSI). Both BAI and water availability increased from 1950 to 1970, and decreased afterwards. Trees were grouped according to their BAI trends in auxological groups (growth-type chronologies), which confirmed that growth of most trees at both sites declined in recent decades, in agreement with increased drought. Because BAI is not expected to decrease without an external forcing, the patterns we uncovered suggest that long-term drought stress has reduced the productivity of beech forests in the central Apennines, in agreement with similar trends identified in other Mediterranean mountains, but opposite to growth trends reported for many forests in central Europe.
Objective: We herein analyze the results of the systematic clinical and angiographic control performed in a series of 77 consecutive patients undergoing minimally invasive coronary artery bypass. Methods and Results: From January 1995 to June 1997, 77 patients underwent minimally invasive coronary artery bypass at our institution. There was one inhospital death, one noncardiac late death, and five patients had to be reoperated for graft malfunction. A total of 76 patients underwentdoi:10.1016/s0022-5223(98)70356-3 pmid:9576211 fatcat:by6hcvzfkbg23n5m4aepzexxjq
more »... angiographic follow-up. In 66 cases (86.8%) the thoracic artery graft, the target vessel, and the anastomosis were patent and functioning normally. In one case the graft was occluded. In the remaining nine cases the thoracic artery graft was patent but with major anomalies of either the anastomosis, the target vessel, or the course of the thoracic artery. Patients operated using especially designed instruments had angiographic results clearly superior to those of patients operated using conventional instrumentation (perfect patency rate 100% vs 81.8%). At a mean follow-up of 18 months, 98.5% of the surviving patients are asymptomatic with negative myocardial scintigraphy. Conclusions: The perfect patency rate of minimally invasive revascularization performed without the use of dedicated instruments is unacceptably low. The use of specific devices is likely to result in a substantial improvement in the angiographic results. (J Thorac Cardiovasc Surg 1998; 115:785-90)
No data are available on the early vasoreactive profile of skeletonized internal thoracic artery grafts. Methods: Fifteen patients undergoing primary isolated coronary artery bypass grafting were randomly assigned to receive a skeletonized or pedicled internal thoracic artery graft. On the second postoperative day all patients were subjected to follow-up angiography and endovascular infusion of serotonin, acetylcholine, and isosorbide dinitrate. Results: Internal thoracic artery grafts weredoi:10.1067/mtc.2003.106 pmid:12658207 fatcat:i5bjktmhjfafnevq7u3oofappa
more »... ly patent in all cases. Mean diameters of the internal thoracic artery were 1.95 Ϯ 0.17 mm in the pedicled group and 2.26 Ϯ 0.40 mm in the skeletonized group. After serotonin challenge, mean internal thoracic artery diameters were reduced to 1.44 Ϯ 0.34 mm and 1.64 Ϯ 0.14 mm, respectively; acetylcholine challenge lead to a moderate degree of vasoconstriction (1.55 Ϯ 0.59 mm in the pedicled group and 1.84 Ϯ 0.15 mm in the skeletonized group). No statistically significant difference was evident between the two groups at any step. Conclusion: Skeletonization does not affect the early vasoreactive profile of internal thoracic artery grafts used for surgical myocardial revascularization. From the
Drugs & Aging
Background. Memantine is an approved symptomatic treatment for moderate to severe Alzheimer's Disease(AD) active on the excitotoxic effects of hyperactive glutamatergic transmission. The mechanism of the effect of memantine in AD patients is poorly known. The default mode network (DMN) is hypoactive in AD and is under glutamatergic control. Objective. To assess the effect of memantine on the activity of the DMN in moderate to severe AD. Methods. fMRI data of 15 moderate to severe AD patients, 7doi:10.2165/11586440-000000000-00000 pmid:21250762 fatcat:ioakyauepjfgblqyfwvd5m2jm4
more »... (age 77±7, MMSE 16±4) treated with memantine and 8 with placebo (age 75±6, MMSE 13±4), were acquired at baseline (T0) and after 6 months of treatment (T6). Resting state components were extracted after spatial normalization on individual patients with independent component analysis. The consistency of the components was assessed using ICASSO and the DMN was recognized through spatial correlation with a predefined template. Voxel-based statistical analyses were performed to study the change of DMN activity from T0 to T6 in the two groups. Results. At T0, the two groups showed similar DMN activity except in the precuneus, where the treated showed slightly greater activity (p<0.05 corrected for family wise error). The prospective comparison between T0 and T6 in the treated showed increased DMN activation mapping to the precuneus (p<0.05 corrected), while the prospective comparison in the untreated did not show significant changes. The treatment x time interaction term was significant at p<0.05 corrected. Conclusions. The results suggest a positive effect of Memantine treatment in moderate to severe AD patients resulting in an increased resting activity in the precuneus region over 6 months. Future confirmatory analysis with adequately powered studies will be required to support the present findings. Disclosure/Conflict of Interest This work has been co-funded by research grant N. 125/2004 of the Italian Ministry of Health, Ricerca Finalizzata "Malattie neurodegenerative legate all'invecchiamento: dalla patogenesi alle prospettive terapeutiche per un progetto traslazionale" and by an unrestricted grant by Lundbeck Italia SpA Pharmaceutical.
Background-This study was conceived to elucidate the clinical and angiographic effects of chronic calcium channel blocker therapy (CCCBT) continued after the first postoperative year in patients in whom the radial artery (RA) was used for myocardial revascularization. Methods and Results-Patients who received RA grafts at our institution and who at 1 year had no scintigraphic evidence of ischemia in the RA territory or angiographic evidence of RA malfunction (nϭ120) were randomly assigned todoi:10.1161/hc37t1.094819 fatcat:3ths4kqq65cjbf4rbpvzcrxbai
more »... tinue (nϭ63) or suspend (nϭ57) the CCCBT with diltiazem (120 mg/d). After 5 years, all patients were reassessed clinically and by stress myocardial scintigraphy, and 87 of them (45 from the continued group that continued CCCBT and 42 from the group that suspended CCCBT) were restudied angiographically. No differences regarding either the clinical and scintigraphic results or the RA angiographic status were demonstrated between the 2 groups. Conclusions-After the first postoperative year, the continuation of CCCBT does not affect RA graft patency or clinical and scintigraphic results. (Circulation. 2001;104[suppl I]:I-64-I-67.)
and the early clinical and angiographic data from the first 109 cases were published in 1996. 8 e report here the 5-year clinical and angiographic results of the first 68 consecutive surviving patients in whom the RA was used as a free graft proximally anastomosed to the aorta. Patients and methods Patient population. From January 1993 to February 1998, 325 patients at our institution underwent myocardial revascularization with the RA as a conduit (13.4% of the isolated coronary artery bypassdoi:10.1016/s0022-5223(98)70054-6 pmid:9832694 fatcat:jg2h4uocqbe4poragklmkqa2p4
more »... ocedures performed in this period). Details of the surgical technique used have already been described elsewhere. 8 In this report we analyze the midterm (5-year) results of the clinical and serial angiographic studies performed on the first 68 consecutive surviving patients in whom the RA was used as a free graft proximally anastomosed to the aorta. The main preoperative characteristics and operative data of these 68 patients are summarized in Tables I through III. 4]    To date, however, no published studies have examined the midterm angiographic fate of RA grafts used for myocardial revascularization. Our experience with the use of the RA started in Objective: To evaluate the midterm angiographic results of the use of radial artery grafts for myocardial revascularization. Methods: The first 68 consecutive surviving patients who received a radial artery graft proximally anastomosed to the aorta at our institution were studied again at 5 years (mean 59 ± 6.5 months) of follow-up; 48 of these patients had previously undergone an early angiographic examination. The response of the radial artery to the endovascular infusion of serotonin was evaluated 1 and 5 years after the operation, and the midterm status of the radial artery graft was correlated with the degree of preoperative stenosis of the target vessel and with calcium-channel blocker therapy. Results: The patency and perfect patency rates of the radial artery grafts 5 years after the operation were 91.9% and 87.0%, respectively. All radial artery grafts that were patent early after the operation remained patent at midterm follow-up, and early parietal irregularities in 7 patients were seen to have disappeared after 5 years. The early propensity toward graft spasm after serotonin challenge was markedly decreased at midterm follow-up. The continued use of calcium-channel antagonists after the first postoperative year did not influence the radial artery graft status, whereas the preoperative severity of the target-vessel stenosis markedly influenced the angiographic results. Conclusions: The midterm angiographic results of radial artery grafts used for myocardial revascularization are excellent. The correct surgical indication is essential. Continued therapy with calcium-channel antagonists after the first year does not influence the midterm angiographic results.
Shwachman-Diamond syndrome is a rare recessive genetic disease caused by mutations in SBDS gene, at chromosome 7q11. Phenotypically, the syndrome is characterized by exocrine pancreatic insufficiency, bone marrow dysfunction, skeletal dysplasia and variable cognitive impairments. Structural brain abnormalities (smaller head circumference and decreased brain volume) have also been reported. No correlation studies between brain abnormalities and neuropsychological features have yet beendoi:10.1016/j.nicl.2015.02.014 pmid:25844324 pmcid:PMC4375735 fatcat:alcfmdnw4faere3ycvzjvsvxze
more »... In this study we investigate neuroanatomical findings, neurofunctional pathways and cognitive functioning of Shwachman-Diamond syndrome subjects compared with healthy controls. To be eligible for inclusion, participants were required to have known SBDS mutations on both alleles, no history of cranial trauma or any standard contraindication to magnetic resonance imaging. Appropriate tests were used to assess cognitive functions. The static images were acquired on a 3 × 0 T magnetic resonance scanner and blood oxygen level-dependent functional magnetic resonance imaging data were collected both during the execution of the Stroop task and at rest. Diffusion tensor imaging was used to assess brain white matter. The Tract-based Spatial Statistics package and probabilistic tractography were used to characterize white matter pathways. Nine participants (5 males), half of all the subjects aged 9-19 years included in the Italian Shwachman-Diamond Syndrome Registry, were evaluated and compared with nine healthy subjects, matched for sex and age. The patients performed less well than norms and controls on cognitive tasks (p = 0.0002). Overall, cortical thickness was greater in the patients, both in the left (+10%) and in the right (+15%) hemisphere, significantly differently increased in the temporal (left and right, p = 0.04), and right parietal (p = 0.03) lobes and in Brodmann area 44 (p = 0.04) of the right frontal lobe. The greatest increases were observed in the left limbic-anterior cingulate cortex (≥43%, p b 0.0004). Only in Broca3s area in the left hemisphere did the patients show a thinner cortical thickness than that of controls (p = 0.01). Diffusion tensor imaging showed large, significant difference increases in both fractional anisotropy (+37%, p b 0.0001) and mean diffusivity (+35%, p b 0.005); the Tract-based Spatial Statistics analysis identified six abnormal clusters of white matter fibres in the fronto-callosal, right fronto-external capsulae, left fronto-parietal, right pontine, temporo-mesial and left anterior-medial-temporal regions. Brain areas activated during the Stroop task and those active during the resting state, are different, fewer and smaller in patients and correlate with worse performance (p = 0.002). Cognitive impairment in Shwachman-Diamond syndrome subjects is associated with diffuse brain anomalies in the grey matter (verbal skills with BA44 and BA20 in the right hemisphere; perceptual skills with BA5, 37, 20, 21, 42 in the left hemisphere) and white matter connectivity (verbal skills with alterations in the fronto-occipital fasciculus and with the inferior-longitudinal fasciculus; perceptual skills with the arcuate fasciculus, limbic and NeuroImage: Clinical 7 (2015) 721-731 ponto-cerebellar fasciculus; memory skills with the arcuate fasciculus; executive functions with the anterior cingulated and arcuate fasciculus).
In progressive myoclonic epilepsy (PME), a rare epileptic syndrome caused by a variety of genetic disorders, the combination of peripheral stimulation and functional magnetic resonance imaging (fMRI) can shed light on the mechanisms underlying cortical dysfunction. The aim of the study is to investigate sensorimotor network modifications in PME by assessing the relationship between neurophysiological findings and blood oxygen level dependent (BOLD) activation. Somatosensory-evoked potentialdoi:10.1038/srep44664 pmid:28294187 pmcid:PMC5353703 fatcat:4ilhtq6b3vfdffipbwkpj4fgqm
more »... P) obtained briefly before fMRI and BOLD activation during median-nerve electrical stimulation were recorded in four subjects with typical PME phenotype and compared with normative data. Giant scalp SSEPs with enlarger N20-P25 complex compared to normal data (mean amplitude of 26.2 ± 8.2 μV after right stimulation and 27.9 ± 3.7 μV after left stimulation) were detected. Statistical group analysis showed a reduced BOLD activation in response to median nerve stimulation in PMEs compared to controls over the sensorimotor (SM) areas and an increased response over subcortical regions (p < 0.01, Z > 2.3, corrected). PMEs show dissociation between neurophysiological and BOLD findings of SSEPs (giant SSEP with reduced BOLD activation over SM). A direct pathway connecting a highly restricted area of the somatosensory cortex with the thalamus can be hypothesized to support the higher excitability of these areas. Progressive myoclonic epilepsies (PMEs) are a group of rare genetic disorders with geographical and ethnic variations, characterized by worsening myoclonus, generalized seizures, and progressive neurological deterioration including cerebellar dysfunction and dementia. PMEs may affect all ages, but typically present in late childhood or adolescence. The prognosis is generally poor, with people with PME eventually wheel-chair bound and with reduced life expectancy 1 . PMEs differ from juvenile myoclonic epilepsy on the following aspects: i) complex phenotype including epilepsy plus movement disorder (action myoclonus); ii) progressive neurological disability; iii) failure to respond to antiepileptic drugs; iv) slowing of background electroencephalographic (EEG) activity 2 ; v) presence of giant evoked potentials 3 . The PMEs core phenotype results from different diseases that have heterogeneous genetic backgrounds, the most frequent being Unverricht-Lundborg disease (ULD), Lafora disease (LD), and other rarer pathologies 4 .
Aim The effects of post-operative left ventricular mass regression (LVMR) on clinical outcome after aortic valve surgery remains to be established. This study was intended to establish the impact of patient characteristics on post-operative survival in patients referred for aortic valve replacement (AVR), with particular regard to LVMR. Methods and results Two hundred and sixty consecutive cases submitted to aortic valve replacement for valvular stenosis were prospectively followed for a meandoi:10.1093/eurheartj/ehi012 pmid:15615799 fatcat:qat4wdywgvfjbl6p7sq6cl5ija
more »... 28+9 months. Baseline, characteristics and extent of LVMR were tested for association with survival by uni-and multivariable analysis. Ten deaths occurred during hospital stay and 52 during out-of-hospital follow-up. Mean left ventricular mass decreased from 190 + 43 to 158 + 70 g/m 2 (P , 0.001). Older age, advanced functional class, hypertension, reduced left ventricle ejection fraction, and high pre-operative left ventricular mass index were associated with reduced survival. Overall the extent of LVMR did not influence the clinical results, while only early (,6 months) LVMR was weakly associated with mid-term outcome. Conclusion Survival after aortic valve surgery is mainly determined by the pre-operative functional cardiac and systemic status. The extent of LVMR does not correlate with clinical outcome, whereas aggressive treatment of hypertension may improve post-operative survival.
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