Showing papers by "Antonio Esposito published in 2013"

Apparent diffusion coefficient modifications in assessing gastro-oesophageal cancer response to neoadjuvant treatment: comparison with tumour regression grade at histology.

Abstract: Objectives To assess changes in apparent diffusion coefficient (ΔADC) and volume (ΔV) after neoadjuvant treatment (NT), and tumour regression grade (TRG) in gastro-oesophageal cancers (GEC), and to discriminate responders from non-responders.

Autologous Pancreatic Islet Transplantation in Human Bone Marrow

Abstract: The liver is the current site of choice for pancreatic islet transplantation, even though it is far from being ideal. We recently have shown in mice that the bone marrow (BM) may be a valid alternative to the liver, and here we report a pilot study to test feasibility and safety of BM as a site for islet transplantation in humans. Four patients who developed diabetes after total pancreatectomy were candidates for the autologous transplantation of pancreatic islet. Because the patients had contraindications for intraportal infusion, islets were infused in the BM. In all recipients, islets engrafted successfully as shown by measurable posttransplantation C-peptide levels and histopathological evidence of insulin-producing cells or molecular markers of endocrine tissue in BM biopsy samples analyzed during follow-up. Thus far, we have recorded no adverse events related to the infusion procedure or the presence of islets in the BM. Islet function was sustained for the maximum follow-up of 944 days. The encouraging results of this pilot study provide new perspectives in identifying alternative sites for islet infusion in patients with type 1 diabetes. Moreover, this is the first unequivocal example of successful engraftment of endocrine tissue in the BM in humans.

Magnetic Resonance Imaging at 7T Reveals Common Events in Age-Related Sarcopenia and in the Homeostatic Response to Muscle Sterile Injury

Abstract: Skeletal muscle remodeling in response to various noxae physiologically includes structural changes and inflammatory events. The possibility to study those phenomena in-vivo has been hampered by the lack of validated imaging tools. In our study, we have relied on multiparametric magnetic resonance imaging for quantitative monitoring of muscle changes in mice experiencing age-related sarcopenia or active regeneration after sterile acute injury of tibialis anterior muscle induced by cardiotoxin (CTX) injection. The extent of myofibrils' necrosis, leukocyte infiltration, and regeneration have been evaluated and compared with parameters from magnetic resonance imaging: T2-mapping (T2 relaxation time; T2-rt), diffusion-tensor imaging (fractional anisotropy, F.A.) and diffusion weighted imaging (apparent diffusion coefficient, ADC). Inflammatory leukocytes within the perimysium and heterogeneous size of fibers characterized aged muscles. They displayed significantly increased T2-rt (P<0.05) and F.A. (P<0.05) compared with young muscles. After acute damage T2-rt increased in otherwise healthy young muscles with a peak at day 3, followed by a progressive decrease to basal values. F.A. dropped 24 hours after injury and afterward increased above the basal level in the regenerated muscle (from day 7 to day 15) returning to the basal value at the end of the follow up period. The ADC displayed opposite kinetics. T2-rt positively correlated with the number of infiltrating leucocytes retrieved by immunomagnetic bead sorting from the tissue (r = 0.92) and with the damage/infiltration score (r = 0.88) while F.A. correlated with the extent of tissue regeneration evaluated at various time points after injury (r = 0.88). Our results indicate that multiparametric MRI is a sensitive and informative tool for monitoring inflammatory and structural muscle changes in living experimental animals; particularly, it allows identifying the increase of T2-rt and F.A. as common events reflecting inflammatory infiltration and muscle regeneration in the transient response of the tissue to acute injury and in the persistent adaptation to aging.

Clinical indications for the use of cardiac MRI. By the SIRM Study Group on Cardiac Imaging

Abstract: Cardiac magnetic resonance (CMR) is considered an useful method in the evaluation of many cardiac disorders. Based on our experience and available literature, we wrote a document as a guiding tool in the clinical use of CMR. Synthetically we describe different cardiac disorders and express for each one a classification, I to IV, depending on the significance of diagnostic information expected.

Beneficial effects of beta-blockers on left ventricular function and cellular energy reserve in patients with heart failure.

Abstract: Beta-blockers have been shown to improve left ventricular (LV) function in patients with heart failure. The aim of this study is to non-invasively assess, by means of in vivo 31P-magnetic resonance spectroscopy (31P-MRS), the effects of beta-blockers on LV cardiac phosphocreatine and adenosine triphosphate (PCr/ATP) ratio in patients with heart failure. Ten heart failure patients on full medical therapy were beta-blocked by either carvedilol or bisoprolol. Before and after 3 months of treatment, exercise testing, 2D echocardiography, MRS, New York Heart Association (NYHA) class, ejection fraction (EF), maximal rate-pressure product and exercise metabolic equivalent system (METS) were evaluated. Relative concentrations of PCr and ATP were determined by cardiac 31P-MRS. After beta-blockade, NYHA class decreased (from 2.2 ± 0.54 to 1.9 ± 0.52, P = 0.05), whereas EF (from 33 ± 7 to 44 ± 6%, P = 0.0009) and METS (from 6.74 ± 2.12 to 8.03 ± 2.39, P = 0.01) increased. Accordingly, the mean cardiac PCr/ATP ratio increased by 33% (from 1.48 ± 0.22 to 1.81 ± 0.48, P = 0.03). Beta-blockade-induced symptomatic and functional improvement in patients with heart failure is associated to increased PCr/ATP ratio, indicating preservation of myocardial high-energy phosphate levels.

Clinical indications for the use of cardiac MRI. By the SIRM Study Group on Cardiac Imaging Indicazioni cliniche per l'utilizzo della cardio RM. A cura del Gruppo di lavoro della Sezione di Cardio-Radiologia della SIRM

Abstract: Cardiac magnetic resonance (CMR) is considered an useful method in the evaluation of many cardiac disorders. Based on our experience and available literature, we wrote a document as a guiding tool in the clinical use of CMR. Synthetically we describe different cardiac disorders and express for each one a classification, I to IV, depending on the significance of diagnostic information expected. Riassunto

Multidetector computed tomography for coronary stents imaging: high-voltage (140-kVp) prospective ECG-triggered versus standard-voltage (120-kVp) retrospective ECG-gated helical scanning.

Abstract: OBJECTIVE To compare prospective electrocardiogram (ECG)-triggered high-voltage coronary computed tomography (CT) angiography (CTA; 140-kVp P-cCTA) with retrospective ECG-gated standard-voltage cCTA (120-kVp R-cCTA), in patients with coronary stents. METHODS Fifty-two patients with coronary stents were studied with 64-slice multidetector scanner. Ninety-three stents were analyzed: 55 with 140-kVp P-cCTA and 38 with 120-kVp R-cCTA. Image quality (IQ), diagnostic confidence (DC), in-stent assessable lumen, artificial narrowing, and effective radiation dose were compared between techniques. RESULTS Image quality and DC were significantly better for the 140-kVp P-cCTA in comparison with the 120-kVp R-cCTA (IQ, 1.1 ± 0.36 vs 1.7 ± 0.60, respectively; P < 0.00001. Diagnostic confidence: 1.1 ± 0.29 vs 1.5 ± 0.65 respectively; P < 0.0001). In-stent assessable lumen and artificial narrowing were comparable between the techniques. Effective dose was lower for the 140-kVp P-cCTA (6.7 ± 2.07 mSv vs 15.8 ± 6.89 mSv; P < 0.0001). CONCLUSIONS High voltage combined with axial prospective ECG-triggered scan improved IQ and DC in stent cCTA imaging but failed to improve the diameter of in-stent assessable lumen and to reduce the artificial narrowing compared with the 120-kVp R-cCTA. Effective dose was 60% lower for the 140-kVp P-cCTA.

Automatic right ventricle segmentation in CT images using a novel multi-scale edge detector approach

Abstract: We present a novel approach for the automatic segmentation of the right ventricle in CT images. We use a level set with a new multi-scale edge stopping function based on spatial oriented filters. This stopping function reduces false edge detection and over-segmentation. The segmentation method was evaluated over 18 CT image studies from healthy and pathologic subjects; results are compared against manual segmentation made by a team of expert radiologists. The mean surface distance error is below 0.64 mm, which proves the effectiveness of the method.

Multi-parametric model of the heart from CT images to guide ventricular tachycardia ablation

Abstract: The purpose of this work was to construct a 3D multi-parametric model of the heart by automatically segmenting cardiac cavities, left myocardium, scar and epicardial fat from multidetector computed tomographic (MDCT) volumes, using a level set algorithm based on a new multi-scale stopping function. This method was applied to 4 patients with recurrent ventricular tachycardia (VT) undergoing contrast enhanced (CE)-MDCT imaging, composed by an angiographic (ANGIO) and a late enhanced (LE) scan, before electro-anatomic mapping (EAM) and radiofrequency ablation (RFa). The segmented structures were integrated into the clinical surgery software system (CARTO). The adequacy of our model was verified by an expert radiologist and an arrhythmologist using a qualitative score.

Cardiac tumors: A pictorial MRI guide for differential diagnosis

Abstract: Poster: "ECR 2013 / C-1276 / Cardiac tumors: A pictorial MRI guide for differential diagnosis" by: "G Ironi, A Esposito, P Marra, F De Cobelli, A Del Maschio; Milan/IT"