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A multileaf collimator (MLC) is an integral component in modern radiotherapy machines as it dynamically shapes the photon field used for patient treatment. Currently, the MLC leaves which collimate the treatment field are mechanically calibrated to ±1 mm every 3 months and during pre-treatment calibration are calibrated to the mechanically set leaf positions. Leaf drift can occur between calibration dates and hence exceed the ±1 mm tolerance. Pre-treatment verification, increases LINAC usage time so is seldom performed for each individual patient treatment, but instead for an acceptable sample of patients and/or treatment fractions. Independent real-time treatment verification is therefore desirable. We are developing a large area CMOS MAPS upstream of the patient to monitor MLC leaf positions for real-time treatment verification. CMOS MAPS are radiation hard for photon and electron irradiation, have high readout speeds and low attenuation which makes them an ideal upstream radiation detector for radiotherapy. Previously, we reported on leaf position reconstruction for single leaves using the Lassena, a 12 × 14 cm2, three side buttable MAPS suitable for clinical deployment. Sobel operator based methods were used for edge reconstruction. It was shown that the correspondence between reconstructed and set leaf position was excellent and resolutions ranged between 60.6 ± 8 and 109 ± 12 μm for a single central leaf with leaf extensions ranging from 1 to 35 mm using 0.3 sec of treatment beam time at 400 MU/min. Here, we report on leaf edge reconstruction using updated methods for complex leaf configurations, as occur in clinical use. Results show that leaf positions can be reconstructed with resolutions of 62 ± 6 μm for single leaves and 86 ± 16 μm for adjacent leaves at the isocenter using 0.15 sec at 400 MU/min of treatment beam. These resolutions are significantly better than current calibration standards.

Aims: Diabetic retinopathy (DR) represents the main cause of blindness among adults in the industrialized Countries. Use of telemedicine could offer an easy, smart specialist fundus oculi examination, as well as putting in a screening programme many patients who otherwise would be excluded. Materials and methods: The NO BLIND is a transversal, multicentre, observational study. Its pilot phase involved nine public outpatient clinics for 6 months. As endpoint of the study, we assessed the prevalence of DR by retinography in a subset of the Italian population. Patients' fundus oculi photos were performed by trained diabetologists through a digital smart ophthalmoscope. Results: According to our endpoint, in the final study population (n = 1461), obtained excluding patients for whom retinography was not able to provide any diagnosis, DR prevalence was equal to 15.5%. According to the receiver operating characteristic (ROC) curve performed, we can observe how retinography appears a highly accurate method to detect DR (AUROC 0.971, 95% confidence interval, 0.954-0.989), with a specificity of the 100% and a sensitivity of the 94.3%. Conclusions: Our findings, in an Italian setting, confirm main data in the literature about DR prevalence. Hence, telemedicine could represent an accurate, fast, and cheap method for screening of DR. © 2018 John Wiley & Sons, Ltd. Aims. Diabetic retinopathy (DR) represents the main cause of blindness among adults in the industrialized Countries. Use of telemedicine could offer an easy, smart specialist fundus oculi examination, as well as putting in a screening program many patients who otherwise would be excluded. Materials and Methods. The NO Blind is a transversal, multicentre, observational study. Its pilot phase involved nine public outpatient clinics for six months. As endpoint of the study, we assessed the prevalence of DR by retinography in a subset of the Italian population. Patients’ fundus oculi photos were performed by trained diabetologists through a digital smart ophthalmoscope. Results. According to our endpoint, in the final study population (n=1461), obtained excluding patients for whom retinography was not able to provide any diagnosis, DR This article is protected by copyright. All rights reserved. prevalence was equal to 15.5%. According to the ROC Curve performed, we can observe how retinography appears a highly accurate method to detect DR (AUROC 0.971 95% C.I. 0.954-0.989), with a specificity of the 100% and a sensitivity of the 94.3%. Conclusions. Our findings, in an Italian setting, confirm main data in the literature about DR prevalence. Hence, telemedicine could represent an accurate, fast and cheap method for screening of DR.

Contribution to Proceedings, Proc. of GPUHEP 2014, 9 - 16; DESY-PROC-2014-05; ISSN 1435-8077

Background and aims Diabetic retinopathy (DR) is the most common microvascular complication of diabetes. Diabetic macroangiopathies, particularly cardiovascular (CV) diseases, seem closely related to diabetes microvascular complications. Aspirin represents the most prescribed compound in CV prevention. Aspirin impact on DR is still object of debate. As it is already recommended among diabetics at high CV risk, aim of this study was to assess a potential relationship between DR and aspirin therapy, in a type 2 diabetes cohort of patients screened through telemedicine. Methods and results NO Blind is a cross-sectional, multicenter, observational study, which involved nine Italian outpatient clinics. Primary endpoint was the assessment of the relationship between aspirin treatment and DR. 2068 patients were enrolled in the study, subsequently split in two subpopulations according to either the presence or absence of DR. Overall, 995 subjects were under aspirin therapy. After adjusting for most common potential confounders, age and gender, aspirin reveals significantly associated with DR (OR: 1.72, 95%CI: 1.58–2.89, p = 0.002) and proliferative DR (PDR) (OR: 1.89, 95%CI: 1.24–2.84, p = 0.003). Association comes lost further adjusting for MACEs (OR: 1.28, 95%CI: 0.85–1.42, p = 0.157) (Model 4) and eGFR (OR: 0.93; 95%CI: 0.71–1.22; p = 0.591) (Model 5). Conclusion In this multicenter cross-sectional study including a large sample of outpatients with T2DM, we showed that aspirin was not associated with DR after adjustment for several cardio-metabolic confounders. However, as partially confirmed by our findings, and related to the well-known pro-hemorrhagic effect of aspirin, its use should be individually tailored, even by telemedicine tools.

The aim of this study was to explore the role of lung ultrasound (LUS) in the diagnosis of SARS-CoV-2 infection and to verify its utility in the prediction of lung disease's severity and outcome. Fifty-three consecutive patients presenting to the Emergency Department of Santa Maria delle Grazie Hospital with high suspicion of SARS-CoV-2 infection underwent diagnostic test for SARS-CoV-2 on samples obtained from nasopharyngeal swab as well as complete proper diagnostic work-up that included clinical evaluation, laboratory tests, blood gas analyses, chest CT and LUS. A semiquantitative analysis of B-lines distribution was performed to calculate the LUS score. Patients were divided into two groups according to the results of both SARS-CoV-2 diagnostic test and other exams (Group A = pneumonia due to SARS-CoV2 infection vs Group B = no SARS-CoV2 infection and another definite diagnosis). LUS showed an excellent accuracy in predicting the diagnosis of SARS-CoV-2 infection (area under the ROC curve of 0.92 with a sensibility of 73% and a specificity of 89% a the cut-off of 12.5). LUS score was more impaired in SARS-CoV-2 patients (18.1 ± 6.0 vs 7.6 ± 5.9, p < 0.00001) and it is significantly negatively correlated with PF ratio values (r = - 0.719, p < 0.0001). An intrahospital mortality rate of 46% was found; patients with adverse outcome had significant higher value of LUS, PF, LDH, and APACHE II score. None of these parameters was predictive of mortality. LUS is a useful tool for the early detection of SARS-CoV-2 infection and for the evaluation of the disease severity, but does not predict mortality. Further studies with repeated evaluations of LUS score are needed to further explore the role of LUS in the assessment of severity in SARS-CoV-2 disease and in the monitoring of the response to treatments.

Aims: To assess the correlation between diabetic retinopathy (DR) and potential risk factors, as well as the relationship between DR and the other complications of diabetes, in a real-life population of type 2 diabetes patients recruited in several centres in Italy. Methods: The NO BLIND is a cross-sectional, multicentre, observational study, which involved nine public outpatient clinics in Italy. The patients were assessed for eligibility from November 2016 till November 2017. Those enrolled underwent standard fundus oculi exam. Clinical and laboratory data were also collected. Results: 2068 T2DM underwent fundus oculi exam. 435 received diagnosis of diabetic retinopathy (21%). Diabetic retinopathy was independently associated with HDL cholesterol (O.R.: 1.042; 95% C.I.: 1.012–1.109; p = 0.004), Albumin Excretion Rate (AER) (O.R.: 1.001; 95% C.I.: 1.000–1.002; p = 0.034) and GFR (O.R.: 1.159; 95% C.I.: 1.039–1.294; p = 0.008). HDL cholesterol values were hence split in two classes according to a potential cut-off (40 mg/dL), as defined by the ROC curve. Following analysis confirmed the association between DR and high HDL values (p = 0.032). Somatic neuropathy and diabetic ulcer were independently related with DR (p < 0.001 and p = 0.012, respectively). Conclusions: A novel relationship between high HDL cholesterol and DR was observed. © 2019 Elsevier B.V. Aims: To assess the correlation between diabetic retinopathy (DR) and potential risk factors, as well as the relationship between DR and the other complications of diabetes, in a real-life population of type 2 diabetes patients recruited in several centres in Italy. Methods: The NO BLIND is a cross-sectional, multicentre, observational study, which involved nine public outpatient clinics in Italy. The patients were assessed for eligibility from November 2016 till November 2017. Those enrolled underwent standard fundus oculi exam. Clinical and laboratory data were also collected. Results: 2068 T2DM underwent fundus oculi exam. 435 received diagnosis of diabetic retinopathy (21%). Diabetic retinopathy was independently associated with HDL cholesterol (O.R.: 1.042; 95% C.I.: 1.012–1.109; p = 0.004), Albumin Excretion Rate (AER) (O.R.: 1.001; 95% C.I.: 1.000–1.002; p = 0.034) and GFR (O.R.: 1.159; 95% C.I.: 1.039–1.294; p = 0.008). HDL cholesterol values were hence split in two classes according to a potential cut-off (40 mg/dL), as defined by the ROC curve. Following analysis confirmed the association between DR and high HDL values (p = 0.032). Somatic neuropathy and diabetic ulcer were independently related with DR (p < 0.001 and p = 0.012, respectively). Conclusions: A novel relationship between high HDL cholesterol and DR was observed.

Muography consists in observing the differential absorption of muons – elementary particles produced through cosmic-ray interactions in the Earth atmosphere – going through the volcano and can attain a spatial resolution of tens of meters. We present here the first experiment of nuclear emulsion muography at the Stromboli volcano. Muons have been recorded during a period of five months by a detector of 0.96 m2 area. The emulsion films were prepared at the Gran Sasso underground laboratory and were analyzed at Napoli, Salerno and Tokyo scanning laboratories. Our results highlight a significant low-density zone at the summit of the volcano with density contrast of 30–40% with respect to bedrock. The structural setting of this part of the volcanic edifice controls the eruptive dynamics and the stability of the “Sciara del Fuoco” slope, which is affected by recurrent tsunamigenic landslides. Periodical imaging of the summit of the Stromboli volcano such as that provided by muography can become a useful method for studying the evolution of the internal structure of the volcanic edifice.

The muon radiography is a novel imaging technique to probe the volcanoes interior, using the capability of high energy cosmic ray muons to penetrate large thicknesses of rock. In this way it is possible to derive a 2D density map along the muon trajectory of volcanic edifices and deduce information on the variations in the rock density distribution, like those expected from dense lava conduits, or low density magma supply paths. This method is applicable also to study geological objects as glaciers, faults, oil underground reservoirs, engineering constructions, where a density contrast is present. Nuclear emulsions are well suited to be employed in this context for their excellent angular resolution; they are compact and robust detectors, able to work in harsh environments without need of power supply. On the other side, a long exposure time is required for a reasonable detector surface (~10 m2) in order to collect a sufficient statistics of muons, and a quasi-real time analysis of the emulsion data is rather difficult due to the scanning time needed by the optical microscopes. Such drawback is on the way to be overcome thanks to a recent R&D program on ultra-fast scanning systems. Muon radiography technique, even if limited to the summit part of the volcano edifice, represents an important tool of investigation, at higher spatial resolution, complementary to the conventional geophysics techniques. The first successful result in this field was obtained by a Japanese group that observed in 2007 the conduit structure of Mt. Asama. Since 2010, other interesting volcanoes have been probed with the same method: Stromboli in 2011, Mt. Teide in 2012 and La Palma in 2014. Here we discuss the muon imaging technique reporting the nuclear emulsion detector design exposed at Stromboli and results of the data analysis.