331 results on '"C, Bartolozzi"'
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2. PERCENTUALI DI PREVALENZA DI ISOLAMENTO DI CEPPI GRE NELL’ANNO 2003 PRESSO LA MICROBIOLOGIA AZIENDA OSPEDALIERA UNIVERSITARIA SENESE NELL’ANNO 2003
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C. Bartolozzi, G. Colombini, S. Franceschelli, S. Banchi, and E. Corsi
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Microbiology ,QR1-502 - Published
- 2004
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3. Patient blood management in cardiac surgery: The 'Granducato algorithm'
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Daniele Marianello, Rita Paniccia, Paolo Del Sarto, Cornel Marusceac, Luca Marchetti, Michele Celiento, Claudia Cariello, Alberto Guadagnucci, Alessandra Pastorino, F. Simeone, Debora Castellani, Paolo Simioni, Sabino Scolletta, Valter Campagnolo, Marco Solinas, Cecilia Bianchi, Pietro Bertini, Paolo Fontanari, C. Bartolozzi, Fabio Guarracino, Dorela Haxhiademi, and Marco Ranucci
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Male ,medicine.medical_specialty ,Blood management ,Blood transfusion ,medicine.medical_treatment ,Blood Loss, Surgical ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Surgical ,medicine ,Patient blood management ,Humans ,Blood Loss ,Blood Transfusion ,030212 general & internal medicine ,Cardiac Surgical Procedures ,Bleeding ,Cardiac surgery ,Transfusion ,Cardiology and Cardiovascular Medicine ,Aged ,Retrospective Studies ,business.industry ,Acute kidney injury ,Retrospective cohort study ,Female ,Follow-Up Studies ,Italy ,Middle Aged ,Algorithms ,medicine.disease ,Prothrombin complex concentrate ,Confidence interval ,Relative risk ,business ,Algorithm ,medicine.drug - Abstract
Background Patients undergoing cardiac surgery are subject to severe alterations of the coagulation system. The four cardiac surgery centers in Tuscany (Italy) structured and shared an algorithm (Granducato Patient Blood Management algorithm, G-PBMa) with predefined interventions for patient blood management. The aim of the study is to analyze the impact of that algorithm on the transfusion needs and bleeding-related outcomes in a large patient population. Methods Multicenter retrospective observational study on 3839 patients undergoing cardiac surgery at the four cardiac centers in Tuscany. The G-PBMa was released at the end of 2015 and it was structured in three parts: pre-, intra-, and post-operative. The year 2014, before the G-PBMa (1955 patients) and the year 2016 (1884 patients) after the G-PBMa in place were compared. Logistic regression analyses were used. Results The main changes introduced were the routine application of viscoelastic tests in bleeding patients (+72%) and the use of fibrinogen and prothrombin complex concentrate (+67%). The G-PBMa resulted in a significant reduction in the overall transfusion rate and in the transfusion rate of the separate blood products (relative risk for transfusions: 0.75, 95% confidence interval 0.65–0.85, P = 0.001). For preoperative hemoglobin values of between 8 and 10 g/dL, the absolute difference in RBC transfusion rate before and after the G-PBMa introduction ranged around 15%–17%. The G-PBMa introduction determined lower ( P = 0.02) chest drain blood loss, lower ( P = 0.001) postoperative acute kidney injury and shorter ( P = 0.001) hospital stay. Conclusions The G-PBMa was effective in reducing blood loss, transfusion requirements, and resulted in a better outcome.
- Published
- 2019
4. ESGAR consensus statement on liver MR imaging and clinical use of liver-specific contrast agents
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Giuseppe Brancatelli, L. Grazioli, Piero Boraschi, T. Helmberger, Jeong Min Lee, B. Op de Beeck, Maria Antonietta Bali, Riccardo Manfredi, Emanuele Neri, Stephen J. Skehan, Elmar M. Merkle, Christoph J. Zech, Celso Matos, Ahmed Ba-Ssalamah, Valérie Vilgrain, C. Bartolozzi, F. Caseiro Alves, Wolfgang Schima, Luis Martí-Bonmatí, Neri, E., Bali, M., Ba-Ssalamah, A., Boraschi, P., Brancatelli, G., Alves, F., Grazioli, L., Helmberger, T., Lee, J., Manfredi, R., Martì-Bonmatì, L., Matos, C., Merkle, E., Op De Beeck, B., Schima, W., Skehan, S., Vilgrain, V., Zech, C., and Bartolozzi, C.
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Radiology, Nuclear Medicine and Imaging ,Delphi Technique ,Statement (logic) ,030218 nuclear medicine & medical imaging ,0302 clinical medicine ,Nuclear Medicine and Imaging ,Delphi technique ,Aumento da Imagem ,Diagnosis ,Medicine ,Imagerie médicale, radiologie, tomographie ,health care economics and organizations ,Neuroradiology ,Settore MED/36 - DIAGNOSTICA PER IMMAGINI E RADIOTERAPIA ,medicine.diagnostic_test ,Liver Cell ,Liver Disease ,Contrast media ,Liver Diseases ,Liver Neoplasms ,Bile Duct ,Interventional radiology ,General Medicine ,Biliary tract ,Liver ,Magnetic resonance imaging ,Magnetic Resonance Imaging ,Radiology Nuclear Medicine and imaging ,Liver Neoplasm ,030220 oncology & carcinogenesis ,Radiology ,Human ,Radiography, Abdominal ,Adenoma ,medicine.medical_specialty ,Consensus ,education ,Reproducibility of Result ,Consensu ,Adenoma, Liver Cell ,Bile Ducts ,Diagnosis, Differential ,Humans ,Reproducibility of Results ,Contrast Media ,03 medical and health sciences ,Abdominal ,Ressonância Magnética ,Meios de Contraste ,Computer. Automation ,business.industry ,Mr imaging ,Clinical trial ,Radiography ,Differential ,Differential diagnosis ,business - Abstract
Objectives: To develop a consensus and provide updated recommendations on liver MR imaging and the clinical use of liver-specific contrast agents. Methods: The European Society of Gastrointestinal and Abdominal Radiology (ESGAR) formed a multinational European panel of experts, selected on the basis of a literature review and their leadership in the field of liver MR imaging. A modified Delphi process was adopted to draft a list of statements. Descriptive and Cronbach’s statistics were used to rate levels of agreement and internal reliability of the consensus. Results: Three Delphi rounds were conducted and 76 statements composed on MR technique (n = 17), clinical application of liver-specific contrast agents in benign, focal liver lesions (n = 7), malignant liver lesions in non-cirrhotic (n = 9) and in cirrhotic patients (n = 18), diffuse and vascular liver diseases (n = 12), and bile ducts (n = 13). The overall mean score of agreement was 4.84 (SD ±0.17). Full consensus was reached in 22 % of all statements in all working groups, with no full consensus reached on diffuse and vascular diseases. Conclusions: The consensus provided updated recommendations on the methodology, and clinical indications, of MRI with liver specific contrast agents in the study of liver diseases. Key points: • Liver-specific contrast agents are recommended in MRI of the liver. • The hepatobiliary phase improves the detection and characterization of hepatocellular lesions. • Liver-specific contrast agents can improve the detection of HCC., SCOPUS: ar.j, info:eu-repo/semantics/published
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- 2016
5. 3D Image Processing : Techniques and Clinical Applications
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D. Caramella, C. Bartolozzi, D. Caramella, and C. Bartolozzi
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- Radiology, Surgery, Gastroenterology, Medical informatics, Computer vision
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Few fields have witnessed such impressive advances as the application of computer technology to radiology. The progress achieved has revolutionized diagnosis and greatly facilitated treatment selection and accurate planning of procedures. This book, written by leading experts from many different countries, provides a comprehensive and up-to-date overview of the role of 3D image processing. The first section covers a wide range of technical aspects in an informative way. This is followed by the main section, in which the principal clinical applications are described and discussed in depth. To complete the picture, the final section focuses on recent developments in functional imaging and computer-aided surgery. This book will prove invaluable to all who have an interest in this complex but vitally important field.
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- 2012
6. Liver Malignancies : Diagnostic and Interventional Radiology
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C. Bartolozzi, R. Lencioni, C. Bartolozzi, and R. Lencioni
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- Radiology, Internal medicine, Gastroenterology, Oncology, Surgery
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In the past few years, striking progress has been made in the diagnosis and treatment of liver malignancies. This book, written by leading experts from throughout the world, provides a comprehensive and up-to-date overview of the role of diagnostic and interventional radiology in respect of liver malignancies. Following background chapters on anatomy, epidemiology, and clinicopathologic features, each of the diagnostic imaging techniques is carefully discussed and appraised, focusing on new developments in equipment and contrast agents. The interventional therapeutic approaches to primary and secondary hepatic malignancies are then described in depth. In particular, full consideration is given to newer sophisticated techniques of liver tumor ablation. The volume also includes special topics such as liver tumors in children and hepatic transplantation. This book will prove an indispensable source of information for clinicians and researchers involved in the diagnostic and therapeutic management of patients with liver malignancies.
- Published
- 2012
7. Efficacy and safety of combination therapy with everolimus and sorafenib for recurrence of hepatocellular carcinoma after liver transplantation
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G. Leonardi, Dania Cioni, Riccardo Lencioni, Irene Bargellini, Davide Ghinolfi, Daniela Campani, C Della Pina, Franco Filipponi, P De Simone, C. Bartolozzi, Luca Pollina, Laura Crocetti, Daniele Pezzati, and Paola Carrai
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Male ,Vascular Endothelial Growth Factor A ,Databases, Factual ,Hepatocellular carcinoma ,medicine.medical_treatment ,Liver transplantation ,Gastroenterology ,Interquartile range ,education.field_of_study ,Liver Neoplasms ,Middle Aged ,Sorafenib ,Treatment Outcome ,Response Evaluation Criteria in Solid Tumors ,Drug Therapy, Combination ,Female ,Patient Safety ,Immunosuppressive Agents ,medicine.drug ,Adult ,Niacinamide ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Combination therapy ,Population ,Antineoplastic Agents ,Internal medicine ,medicine ,Humans ,Everolimus ,education ,Aged ,Retrospective Studies ,Sirolimus ,Transplantation ,business.industry ,Patient Selection ,Phenylurea Compounds ,medicine.disease ,Surgery ,Neoplasm Recurrence, Local ,business ,Proto-Oncogene Proteins c-akt ,Liver Failure - Abstract
Background Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) is still associated with a dismal outcome. Combination therapy with everolimus (EVL) and vascular endothelial growth factor inhibitor sorafenib (SORA) is based on the role of both b-Raf and mammalian target of rapamycin/protein kinase B pathways in the pathogenesis of HCC and is being investigated in clinical practice. Methods This was a single-center retrospective analysis on LT recipients with unresectable HCC recurrence and undergoing combination therapy with EVL and SORA. Patients were included if they were switched to EVL+SORA at any time after surgery. Primary endpoint was overall survival (OS) after both LT and recurrence, and response to treatment based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) in the intention-to-treat (ITT) population. Secondary analysis was safety of combination therapy with EVL and SORA in the population of patients who received ≥1 dose of the study drug. Results Seven patients (100% male; median age 53 years [interquartile range (IQR) 9 years]) were considered for analysis. HCC recurrence was diagnosed at a median (IQR) interval since LT of 9 (126) months, and patients were administered EVL+SORA at a median interval since LT of 11 (126) months. Baseline immunosuppression was with tacrolimus (TAC) in 2 patients (28.6%), cyclosporine (CsA) in 2 (28.6%), and EVL monotherapy in 3 (42.8%). At a median (IQR) follow-up of 6.5 (14) months, 5 patients (71.4%) were alive, 4 of them (57.1%) with tumor progression according to the mRECIST criteria. Median (IQR) time to progression was 3.5 (12) months. Two patients died at a median (IQR) follow-up of 5 (1) months owing to tumor progression in 1 patient (14.3%) and sepsis in the other (14.3%). EVL monotherapy was achieved in 6 patients (85.7%), whereas 1patient (14.3%) could not withdraw from calcineurin inhibitor owing to acute rejection. Treatment complications were: hand-foot syndrome in 5 patients (71.4%), hypertension in 1 (14.3%), alopecia in 1 (14.3%), hypothyroidism in 1 (14.3%), diarrhea in 2 (28.6%), pruritus in 1 (14.3%), abdominal pain in 1 (14.3%), rash in 1 (14.3%), asthenia in 3 (42.8%), anorexia in 3 (42.8%), and hoarseness in 2 (28.6%). Adverse events led to temporary SORA discontinuation in 2 patients (28.6%) and to SORA dose reduction in 3 (42.8%). Conclusions Treatment of HCC recurrence after LT with a combination regimen of EVL+ SORA is challenging because of SORA-related complications. Longer follow-up periods and larger series are needed to better capture the impact of such combination treatment on tumor progression and patient survival.
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- 2014
8. Identification of responders to sorafenib in hepatocellular carcinoma: is tumor volume measurement the way forward?
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V. Mismas, Rodolfo Sacco, F. Letterio, G. Bresci, G. Masi, R. Fiorile, Irene Bargellini, A. Scionti, Caterina Vivaldi, C. Bartolozzi, and C. Caparello
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Male ,Niacinamide ,Oncology ,Sorafenib ,Cancer Research ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Internal medicine ,Biomarkers, Tumor ,Carcinoma ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Survival rate ,Aged ,Retrospective Studies ,Predictive marker ,Hepatology ,business.industry ,Phenylurea Compounds ,Liver Neoplasms ,Gastroenterology ,Retrospective cohort study ,General Medicine ,medicine.disease ,Survival Rate ,Response Evaluation Criteria in Solid Tumors ,Hepatocellular carcinoma ,Female ,Tumour volume ,Identification (biology) ,Tomography, X-Ray Computed ,Nuclear medicine ,business ,medicine.drug - Abstract
Objectives: Early assessment of hepatocellular carcinoma (HCC) response during sorafenib (SO) treatment is challenging, since tumor necrosis, extension and radiological appearance can be inhomogeneous. We evaluated the predictive value of different imaging criteria - such as Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, European Association for the Study of the Liver (EASL), modified RECIST (mRECIST), tumor density and volume variations - in the early follow-up of SO treatment. Methods: The study included 22 patients. CT images from baseline and 2 months were reviewed to assess response according to RECIST 1.1, mRECIST, EASL, Choi's criteria (decreased tumor density by ≥15%) and arterial-enhancing tumor volume ratio; α-fetoprotein (AFP) variations were expressed as AFP ratio. Results: The response criteria and volume measurements were reproducible (k > 0.80). The overall disease control rate was 40.9% by EASL and mRECIST, and 27.3% by RECIST 1.1; a ≥15% decrease in tumor density was observed in 9 patients (40.9%). The mean volume ratio was 1.73 ± 2.12, the mean AFP ratio 14 ± 37. The 1-year survival rate was 65.9%. Volume ratio was the only predictive factor for survival, with 1-year cumulative survival rates of 90% for volume ratios ≤1.1 and of 45.4% for volume ratios >1.1 (p = 0.04). Conclusions: Tumor volume measurements are reproducible and might provide an early predictive marker of response in HCC patients treated with SO.
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- 2013
9. Diffusion-weighted imaging in patients with progressive multifocal leukoencephalopathy
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L Del Bono, G Doria, S De Cori, Luigi Murri, Mc Michelassi, Marco Giannelli, C. Bartolozzi, Mirco Cosottini, and C. Tavarelli
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Adult ,Male ,medicine.medical_specialty ,Fluid-attenuated inversion recovery ,Statistics, Nonparametric ,White matter ,Lesion ,Leukoencephalopathy ,Image Processing, Computer-Assisted ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Aged ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Progressive multifocal leukoencephalopathy ,Leukoencephalopathy, Progressive Multifocal ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,medicine.disease ,Hyperintensity ,Diffusion Magnetic Resonance Imaging ,medicine.anatomical_structure ,Female ,Radiology ,medicine.symptom ,business ,Nuclear medicine ,Diffusion MRI - Abstract
Progressive multifocal leukoencephalopathy (PML) is a severe demyelinating disease of the central nervous system due to JC polyoma virus infection of oligodendrocytes. PML develops in patients with impaired T-cell function as occurs in HIV, malignancy or immunosuppressive drugs users. Until now no imaging methods have been reported to correlate with clinical status. Diffusion-weighted imaging (DWI) is a robust MRI tool in investigating white matter architecture and diseases. The aim of our work was to assess diffusion abnormalities in focal white matter lesions in patients with PML and to correlate the lesion load measured with conventional MRI and DWI to clinical variables. We evaluated eight patients with a biopsy or laboratory-supported diagnosis of PML. All patients underwent MRI including conventional sequences (fluid attenuated inversion recovery-FLAIR) and DWI. Mean diffusivity (MD) maps were used to quantify diffusion on white matter lesions. Global lesion load was calculated by manually tracing lesions on FLAIR images, while total, central core and peripheral lesion loads were calculated by manually tracing lesions on DWI images. Lesion load obtained with the conventional or DWI-based methods were correlated with clinical variables such as disease duration, disease severity and survival. White matter focal lesions are characterized by a central core with low signal on DWI images and high MD (1.853 x 10(-3) mm2/s), surrounded by a rim of high signal intensity on DWI and lower MD (1.1 x 10(-3) mm2/s). The MD value of normal-appearing white matter is higher although not statistically significant (0.783 x 10(-3) mm2/s) with respect to control subjects (0.750 x 10(-3) mm2/s). Inter-rater correlations of global lesion load between FLAIR (3.96%) and DWI (3.43%) was excellent (ICC=0.87). Global lesion load on FLAIR and DWI correlates with disease duration and severity (respectively, p=0.037, p=0.0272 with Karnofsky scale and p=0.0338 with EDSS on FLAIR images; p=0.043, p=0.0296 with Karnofsky scale and p=0.0365 with EDSS on DW images). Central core lesion load on DWI correlates with disease duration and severity (respectively p=0.043, p=0.0103 with Karnofsky scale and p=0.0112 with EDSS), while peripheral lesion load does not correlate with any clinical variable. The global lesion load in PML correlates with disease duration and severity. DWI images, which can distinguish within lesions a central core from a peripheral rim, reveal that a larger central core component correlates to a worsened clinical status and longer disease duration. On the other hand the peripheral rim lesion load visualized on DWI images does not correlate with clinical variables and does not achieve obtaining further prognostic information with respect to conventional imaging.
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- 2008
10. DIFFERENTIAL ACTIVATION OF MITOGEN-ACTIVATED PROTEIN KINASE SIGNALLING PATHWAYS IN THE HIPPOCAMPUS OF CRND8 TRANSGENIC MOUSE, A MODEL OF ALZHEIMER'S DISEASE
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Fiorella Casamenti, C. Bartolozzi, Arianna Bellucci, Daniele Nosi, Maria Grazia Giovannini, C. Melani, Cristina Grossi, and Francesca Cerbai
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MAPK/ERK pathway ,medicine.medical_specialty ,Blotting, Western ,Hippocampus ,Mice, Transgenic ,Amyloid beta-Protein Precursor ,Mice ,Alzheimer Disease ,Internal medicine ,medicine ,Amyloid precursor protein ,Animals ,Humans ,Cholinergic neuron ,Microscopy, Confocal ,biology ,Microglia ,Kinase ,General Neuroscience ,JUN kinase ,Immunohistochemistry ,Cell biology ,Enzyme Activation ,Disease Models, Animal ,Endocrinology ,medicine.anatomical_structure ,Mitogen-activated protein kinase ,Mutation ,biology.protein ,Mitogen-Activated Protein Kinases ,Signal Transduction - Abstract
Transgenic Centre for Research in Neurodegenerative Diseases 8 (TgCRND8) mice expressing a double mutant form of human amyloid precursor protein represent a good model of Alzheimer's disease, and can be useful to clarify the involvement of mitogen-activated protein kinases (MAPK) dysregulation in the pathophysiology of this neurodegenerative disorder. Activation of extracellular regulated kinase (ERK) 1/2, jun kinase (JNK) and p38MAPK was studied in the hippocampus of 7-month-old TgCRND8 mice by immunohistochemistry and Western blot analysis using antibodies selective for the phosphorylated, and thus active, forms of the enzymes. We demonstrated that the three main MAPK pathways were differentially activated in cells of the hippocampus of TgCRND8 mice in comparison to wild type (Wt) littermates, p38MAPK and JNK being more activated, while ERK less activated. p38MAPK was significantly activated in microglia, astrocytes and neurons, around and distant from the plaques. JNK was highly activated in cells closely surrounding the plaques. No difference was observed in the activation of the two major bands of JNK, at a molecular weight of 46 kDa and 54 kDa. These data indicate the possible involvement of p38MAPK and JNK pathways dysregulation in the pathogenesis of Alzheimer's disease. The ERK2 isoform of the ERK pathway was less activated in the hippocampal dentate gyrus of Tg mice in basal conditions. Furthermore activation of the ERK pathway by ex vivo cholinergic stimulation with carbachol caused significantly higher activation of ERK in the hippocampus of Wt mice than in Tg mice. These findings may pose a molecular basis for the memory disruption of Alzheimer's disease, since proper functioning of the basal forebrain cholinergic neurons and of ERK2 is critical for memory formation.
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- 2008
11. Ileocecal valve imaging on computed tomographic colonography
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C. Bartolozzi, M Fracchia, G. Galatola, T Gallo, Emanuele Neri, Paola Vagli, Daniele Regge, and G. Nieddu
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Adult ,Male ,medicine.medical_specialty ,Supine position ,Virtual colonoscopy ,Urology ,Colonoscopy ,Cecum ,Ileocecal valve ,Image Processing, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Computed Tomographic Colonography ,Aged ,Aged, 80 and over ,Ileocecal Valve ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Gastroenterology ,General Medicine ,Middle Aged ,Endoscopy ,Prone position ,medicine.anatomical_structure ,Female ,Radiology ,business ,Colonography, Computed Tomographic - Abstract
The aim of our study was to describe the visualization, normal anatomy, and variations of the ileocecal valve with computed tomographic (CT) colonography to provide information about its optimal imaging. We analyzed data in two- and three-dimensional rendering mode in 71 consecutive patients who underwent routine CT colonoscopy followed by conventional colonoscopy for confirmation of the radiologic findings. Complete visualization of the ileocecal valve was better achieved in the supine than in the prone position (82% vs. 62%, respectively); the ileocecal valve appeared in 64% of cases in the supine position when it was invisible in prone position (p < 0.0001). Partial visualization of the ileocecal valve was possible in 94% of cases. The ileocecal valve was of labial type in 76%, papillary type in 21%, and lipomatous in 3% of cases. The orifice was identified in 53% of ileocecal valves; in two cases of cecal carcinoma, the normal ileocecal valve morphology was grossly disrupted. The ileocecal valve was at least partly visualized by CT colonoscopy in 94% of cases, more frequently in the supine position. Its most common normal morphology is the labial type. The absence of orifice visualization alone is not a specific sign for neoplasia, but its presence helps distinguish physiologic bulging from neoplasia.
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- 2005
12. PERCENTUALI DI PREVALENZA DI ISOLAMENTO DI CEPPI GRE NELL’ANNO 2003 PRESSO LA MICROBIOLOGIA AZIENDA OSPEDALIERA UNIVERSITARIA SENESE NELL’ANNO 2003
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S. Franceschelli, E. Corsi, S. Banchi, C. Bartolozzi, and G. Colombini
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lcsh:QR1-502 ,General Medicine ,lcsh:Microbiology - Published
- 2004
13. Role of interventional radiology in the management of vascular complications after liver transplantation
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M. Perri, Lucio Urbani, C. Bartolozzi, Pasquale Petruzzi, Irene Bargellini, Franco Filipponi, Claudio Vignali, Roberto Cioni, and A Cicorelli
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Transplantation ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Biopsy ,medicine.medical_treatment ,Interventional radiology ,Thrombolysis ,Liver transplantation ,medicine.disease ,Liver Transplantation ,Surgery ,Venous thrombosis ,Angioplasty ,Balloon dilation ,Humans ,Medicine ,Portal hypertension ,Vascular Diseases ,Radiology ,Embolization ,Tomography, X-Ray Computed ,business - Abstract
The purpose of this study is to review the role of the percutaneous interventional procedures in the treatment of vascular complications after orthotopic liver transplantations (OLT). Vascular complications, such as arterial stenosis and venous thrombosis, which occur in approximately 1% to 10% of liver transplant patients, are associated with a higher risk of graft dysfunction. Percutaneous interventional procedures, including angioplasty, local thrombolysis, and embolization, are useful to manage these complications. A reduced blood loss and a low incidence of procedural complications allow for rapid recovery. Hepatic arterial and portal vein anastomotic stenosis can be treated effectively by means of balloon dilation; stenting has also been proposed, particularly for venous complications. Infusional local thrombolysis may be useful in venous thrombosis. Arteriovenous fistulas, occurring at the level of the anastomosis or after liver biopsy, require intraarterial embolization using microcoils or gelfoam. Timing of the intervention for the treatment of ischemic complications is of outmost importance to guarantee liver functional recovery and avoid irreversible parenchymal injuries. Other interventional procedures may be extremely useful to manage portal hypertension after OLT; for example, by creation of transjugular portosystemic shunts, or, in the case of associated hypersplenism, transarterial embolization of the splenic artery. Finally, in patients with recurrent hepatitis, the transjugular approach has been shown to be safe and effective for liver biopsy, whereas transarterial chemoembolization may be extremely useful to treat recurrent hepatocarcinoma.
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- 2004
14. Diagnosis and treatment of hepatic artery stenosis after orthotopic liver transplantation
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Irene Bargellini, Franco Filipponi, Roberto Cioni, C. Bartolozzi, Claudio Vignali, Pasquale Petruzzi, M Lazzereschi, A Cicorelli, and Lucio Urbani
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Adult ,Male ,medicine.medical_specialty ,Percutaneous ,Arterial Occlusive Diseases ,Anastomosis ,Hepatic Artery ,Postoperative Complications ,Humans ,Medicine ,Aged ,Retrospective Studies ,Transplantation ,Arterial dissection ,medicine.diagnostic_test ,business.industry ,Vascular disease ,Retrospective cohort study ,Digital subtraction angiography ,Middle Aged ,medicine.disease ,Liver Transplantation ,Stenosis ,surgical procedures, operative ,medicine.anatomical_structure ,Female ,Surgery ,Radiology ,Tomography, X-Ray Computed ,business ,Artery - Abstract
Purpose The purpose of this study was to evaluate the accuracy of Multidetector Computed Tomographic Angiography (MDCTA) to detect hepatic artery (HA) stenosis after orthotopic liver transplantation (OLT) and the efficacy of treatment using percutaneous transluminal angioplasty (PTA). Materials and methods Twenty-two consecutive patients with OLT underwent MDCTA for evaluation of HA, followed by digital subtraction angiography (DSA) (gold standard). Source images (Ax) were processed, obtaining multiplanar reformations (MPRs), maximum intensity projections (MIPs), and volume renderings (VRs). Images were evaluated to identify the following: (1) arterial depiction (celiac axis, anastomosis, and left [LHA] and right [RHA] HA), (2) detection of stenoses, and (3) grading of stenoses. Indications for PTA were set at MDCTA and DSA, and PTA was performed when appropriate. Results MDCTA depicted the celiac axis and anastomoses in all patients; LHA and RHA were visualized in 21 of 22 patients with Ax, MPRs, and MIPs, and in 17 of 22 with VRs. All reconstruction modalities enabled correct diagnosis of celiac (n = 3) and anastomotic stenoses (n = 14). Of 6 LHA and RHA stenoses, 4 (66.7%) were visualized with Ax, MPRs, and VRs, and 5 (83.3%) were visualized with MIPs. Stenosis was overestimated in 9 (39.1%) cases with VRs and in 3 (13%) with the other modalities. PTA was performed in 8 cases, with 1 case of arterial dissection requiring re-OLT. At a median follow-up of 28 months, the primary and secondary patency rates were 71.4% (5 of 7) and 85.7% (6 of 7), respectively. Conclusions MDCTA and accurate postprocessing enable confident depiction of the arterial anatomy and detection of stenosis after OLT. PTA is safe and allows allograft saving, at least until another suitable donor becomes available.
- Published
- 2004
15. Contrast-enhanced three-dimensional MR angiography of neck vessels: does dephasing effect alter diagnostic accuracy?
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Mc Michelassi, R Calabrese, Michele Puglioli, Mirco Cosottini, Virna Zampa, C. Bartolozzi, Luigi Murri, and Simona Ortori
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Male ,medicine.medical_specialty ,Carotid Artery, Common ,Dephasing ,Vertebral artery ,Contrast Media ,Diagnostic accuracy ,Sensitivity and Specificity ,Severity of Illness Index ,Imaging, Three-Dimensional ,Predictive Value of Tests ,medicine.artery ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Carotid Stenosis ,Prospective Studies ,Neuroradiology ,Aged ,Probability ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Neck vessels ,Ultrasound ,Angiography, Digital Subtraction ,General Medicine ,Digital subtraction angiography ,Middle Aged ,medicine.disease ,body regions ,Radiographic Image Enhancement ,Stenosis ,Female ,Radiology ,business ,Carotid Artery, Internal ,Magnetic Resonance Angiography - Abstract
The aim of this study was to evaluate diagnostic accuracy of contrast-enhanced MRA (CEMRA) compared with digital subtraction angiography (DSA) in studying neck vessels of 48 patients. In three groups of patients, we used three MRA protocols differing for voxel size to assess if intravoxel dephasing effects could modify accuracy of CEMRA. Accuracy and correlation with DSA results were calculated in all patients and separately in the three groups. A qualitative analysis of the likeness between morphology of the stenosis in CEMRA and DSA images was also assessed. In all patients accuracy and agreement with DSA were 96% and k=0.85 in subclavian arteries, 96% and k=0.84 in vertebral artery, 97% and k=0.88 in common carotid arteries, and 94% and k=0.86 in internal carotid arteries. In the three groups accuracy and agreement with DSA did not show any significant difference. Qualitative analysis of CEMRA and DSA images revealed a better agreement in depicting the morphology of stenosis using a smaller voxel size. The CEMRA represents a powerful tool for the non-invasive evaluation of neck vessels. Overestimation trend of CEMRA is confirmed and the reduction of voxel size, decreasing the dephasing intravoxel effect, allows to have a better overlapping of stenosis morphology on CEMRA compared with DSA, but it does not yield diagnostic gain in the stenosis grading.
- Published
- 2003
16. LARGE VESTIBULAR AQUEDUCT IN DISTAL RENAL TUBULAR ACIDOSIS. HIGH-RESOLUTION MR IN THREE CASES
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Stefano Sellari-Franceschini, Francesca Ravecca, Francesca Forli, Emanuele Neri, M Panconi, M. Massimetti, C. Bartolozzi, and Stefano Berrettini
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Male ,medicine.medical_specialty ,Vestibular aqueduct ,Adolescent ,Hearing loss ,medicine.medical_treatment ,Hearing Loss, Sensorineural ,Vestibular Aqueduct ,Distal renal tubular acidosis ,Internal medicine ,otorhinolaryngologic diseases ,medicine ,Valsalva maneuver ,Humans ,In patient ,Radiology, Nuclear Medicine and imaging ,Inner ear ,Child ,Vestibular system ,Radiological and Ultrasound Technology ,business.industry ,Anatomy ,General Medicine ,Acidosis, Renal Tubular ,medicine.disease ,Minor head trauma ,Magnetic Resonance Imaging ,Surgery ,medicine.anatomical_structure ,Child, Preschool ,Cardiology ,Disease Progression ,Sensorineural hearing loss ,Female ,sense organs ,medicine.symptom ,business ,Kidney disease - Abstract
High-resolution MR of the inner ear performed in 3 consecutive pediatric patients affected by distal renal tubular acidosis (dRTA) and progressive sensorineural hearing loss (SNHL) revealed enlarged vestibular aqueducts (LVA) (bilateral in 1 case and unilateral in 2). LVA is associated to sporadic, progressive SNHL, often secondary to minor head trauma and activities involving the Valsalva maneuver. We believe that the presence of LVA may have contributed to the onset of SNHL and its progression in our patients, and therefore want to stress the importance of morphological studies of the inner ear in patients affected by dRTA and SNHL.
- Published
- 2001
17. Spiral CT virtual endoscopy of abdominal arteries: clinical applications
- Author
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Emanuele Neri, Roberto Cioni, Claudio Vignali, C. Bartolozzi, G Bonanomi, Mauro Ferrari, and Pasquale Petruzzi
- Subjects
Radiography, Abdominal ,medicine.medical_specialty ,Urology ,Renal Artery Obstruction ,Iliac Artery ,Diagnosis, Differential ,Aortic aneurysm ,User-Computer Interface ,Aneurysm ,Renal Artery ,Celiac Artery ,medicine.artery ,medicine ,Fiber Optic Technology ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Aorta, Abdominal ,Renal artery ,Aorta ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Abdominal aorta ,Gastroenterology ,Angiography ,Reproducibility of Results ,Endoscopy ,General Medicine ,medicine.disease ,Stenosis ,medicine.anatomical_structure ,cardiovascular system ,sense organs ,Radiology ,business ,Tomography, X-Ray Computed ,Splenic Artery ,Artery ,Aortic Aneurysm, Abdominal - Abstract
Virtual endoscopy enables the creation of endoluminal views of the aorta and its branches by processing spiral computed tomographic (CT) images, thereby allowing the preoperative and postoperative evaluations of abdominal aortic aneurysms, aneurysms of the splenic, celiac, and common iliac arteries, and renal artery stenoses. Moreover, it is helpful for verifying the position of stents and endoprostheses from within the aortic lumen. This method is a promising addition to spiral CT.
- Published
- 2000
18. Magnetic resonance virtual endoscopy of the common bile duct stones
- Author
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Davide Caramella, Piero Boraschi, ED Lehmann, C. Bartolozzi, G Braccini, G Perri, and Emanuele Neri
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,Common bile duct ,business.industry ,General surgery ,Magnetic resonance imaging ,Gallstones ,Hepatology ,Magnetic Resonance Imaging ,Sensitivity and Specificity ,medicine.anatomical_structure ,Case-Control Studies ,Internal medicine ,Image Processing, Computer-Assisted ,medicine ,Humans ,Surgery ,Virtual endoscopy ,business ,Abdominal surgery - Published
- 1999
19. IMAGING EVALUATION OF TUMOR RESPONSE
- Author
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C. Bartolozzi, G Granai, Riccardo Lencioni, Francescamaria Donati, and Dania Cioni
- Subjects
medicine.medical_specialty ,Cirrhosis ,business.industry ,medicine.medical_treatment ,Mortality rate ,medicine.disease ,Lesion ,Coagulative necrosis ,Hepatocellular carcinoma ,medicine ,Radiology ,Hepatectomy ,Percutaneous ethanol injection ,medicine.symptom ,Transcatheter arterial chemoembolization ,business - Abstract
With advances in imaging and surgical techniques, the number of patients undergoing partial hepatectomies for primary or secondary liver tumors have significantly increased during the past decade. Improvements in imaging modalities have contributed to early detection, precise localization and characterization of liver lesions (Meun 1998). Refinements in surgical techniques have reduced both the morbidity and the mortality rates from elective hepatectomy and have allowed surgeons to consider more extensive resections. Nevertheless, in most patients with liver tumors, surgery is not an appropriate option. Patients with primary hepatocellular carcinoma (HCC) are often poor surgical candidates, because of the lack of hepatic reserve resulting from coexisting liver cirrhosis or the presence of multiple lesions at the time of the diagnosis (Lencioni and Also, in most patients with hepatic metastases resec-tion is not feasible because the lesion is adjacent to critical vascular structures or too many segments are involved that resection would not leave enough liver tissue for survival (Steele and Ravikumar 1989).
- Published
- 1999
20. Pseudoaneurysm of the abdominal aorta: evaluation with virtual angioscopy of spiral-CT data sets
- Author
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C. Bartolozzi, Davide Caramella, Claudio Vignali, Roberto Cioni, Emanuele Neri, and F Trincavelli
- Subjects
Male ,medicine.medical_specialty ,Angioscopy ,Lumen (anatomy) ,Blood Vessel Prosthesis Implantation ,User-Computer Interface ,Pseudoaneurysm ,medicine.artery ,Surgical Wound Dehiscence ,Image Processing, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Aorta ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Abdominal aorta ,Angiography, Digital Subtraction ,General Medicine ,Middle Aged ,medicine.disease ,medicine.anatomical_structure ,cardiovascular system ,Abdomen ,Radiology ,Tomography ,Tomography, X-Ray Computed ,business ,Aneurysm, False ,Aortic Aneurysm, Abdominal - Abstract
We describe a case of graft-related pseudoaneurysm of the abdominal aorta evaluated with spiral CT and DSA. Spiral CT data sets were processed to obtain surface-rendered internal views (virtual angioscopy, VA) of the graft and the pseudoaneurysm, and to demonstrate from inside the lumen the site of dehiscence. A jet flow phenomenon inside the pseudoaneurysm was observed at DSA. Spiral-CT axial images, multiplanar volume reconstructions with maximum intensity projections, and shaded surface display showed the site of rupture. The VA findings were: (a) from inside the graft lumen, the evidence of a communication canal between the graft and the pseudoaneurysm; and (b) from inside the pseudoaneurysm, the presence of a jet flow. The VA findings showed good correlation with those obtained with the other imaging techniques.
- Published
- 1999
21. MR virtual endoscopy of the pancreaticobiliary tract: a feasible technique?
- Author
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G Braccini, Davide Caramella, Riccardo Lencioni, R Gigoni, G Perri, Piero Boraschi, Emanuele Neri, and C. Bartolozzi
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Biliary Tract Diseases ,Urology ,Mr cholangiopancreatography ,User-Computer Interface ,Image Processing, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Endoscopy, Digestive System ,Virtual endoscopy ,Biliary Tract ,Pancreas ,Aged ,Medical systems ,Aged, 80 and over ,Cholangiopancreatography, Endoscopic Retrograde ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Gastroenterology ,Pancreatic Diseases ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,Magnetic Resonance Imaging ,Endoscopy ,Virtual image ,Feasibility Studies ,Female ,Surface rendering ,Radiology ,business ,Biliary tract disease - Abstract
To evaluate the feasibility of magnetic resonance (MR) virtual endoscopy of the pancreaticobiliary tract by using MR cholangiopancreatography (MRCP) data sets as source images, we retrospectively reviewed MRCP data sets of 120 patients with Navigator software (GE/Medical Systems, Milwaukee, WI) that allowed display of inner views by surface rendering the internal wall of the bile ducts with simulated light and shadow.
- Published
- 1999
22. HEPATOCELLULAR CARCINOMA
- Author
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R. Lencioni, D. Cioni, and C. Bartolozzi
- Published
- 1999
23. RADIOFREQUENCY THERMAL ABLATION OF HEPATOCELLULAR CARCINOMA
- Author
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Riccardo Lencioni, E Buscarini, Luigi Buscarini, C. Bartolozzi, and Dania Cioni
- Subjects
Hyperthermia ,medicine.medical_specialty ,Cirrhosis ,Percutaneous ,business.industry ,medicine.medical_treatment ,Thermal ablation ,medicine.disease ,digestive system diseases ,Coagulative necrosis ,Hepatocellular carcinoma ,medicine ,Radiology ,Percutaneous ethanol injection ,business ,High recurrence rate - Abstract
Minimally invasive percutaneous therapies, such as percutaneous ethanol injection (PEI) or interstitial hyperthermia obtained by radiofrequency (RF) have now been accepted by many groups as first step treatment of hepatocellular carcinoma (HCC) in cirrhosis’, taking into account the surgical risk and the very high recurrence rate, which are characteristic of this tumour.
- Published
- 1999
24. Local staging of prostate carcinoma with endorectal coil MRI: correlation with whole-mount radical prostatectomy specimens
- Author
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C. Bartolozzi, A Bozza, Riccardo Lencioni, Andrea Amorosi, Sergio Serni, Alberto Lapini, Marco Carini, Antonio Manganelli, G Barbanti, and I. Menchi
- Subjects
Male ,medicine.medical_specialty ,medicine.medical_treatment ,Sensitivity and Specificity ,Prostate cancer ,Prostate ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Stage (cooking) ,Neoplasm Staging ,Neuroradiology ,Prostatectomy ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Prostatic Neoplasms ,Magnetic resonance imaging ,Interventional radiology ,General Medicine ,medicine.disease ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Radiology ,business - Abstract
The purpose of this study was to investigate the accuracy of endorectal coil MRI in the local staging of prostate carcinoma. A total of 73 patients with biopsy-proven prostate carcinoma were examined at 0.5 T prior being submitted to radical prostatectomy. The gold standard was provided in all patients by findings at whole-mount sectioning of the surgical specimens. At pathology 28 patients had stage T2, 30 had stage T3a/b, and 15 had stage T3c lesions. Overall accuracy of endorectal coil MRI in defining local tumor stage was 82% (60 of 73 patients). Of 73 patients, 5 (7%) were underestimated and 8 (11%) overestimated. The sensitivity and the specificity of endorectal coil MRI in diagnosing capsular penetration were 95% and 82%, respectively. Seminal vesicle invasion was detected with 80% sensitivity and 93% specificity. Our data indicate that endorectal coil MRI is an accurate method for local staging of prostate cancer.
- Published
- 1996
25. Thyroid blood flow evaluation by color-flow Doppler sonography distinguishes Graves' disease from Hashimoto's thyroiditis
- Author
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C. Bartolozzi, Enio Martino, Aldo Pinchera, M. Lampis, A. De Liperi, Teresa Rago, Sandra Brogioni, Salvatore Mazzeo, and Paolo Vitti
- Subjects
Male ,endocrine system ,medicine.medical_specialty ,Pathology ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Graves' disease ,Thyroid Gland ,Gastroenterology ,Thyroiditis ,Diagnosis, Differential ,Endocrinology ,medicine.artery ,Internal medicine ,medicine ,Humans ,Euthyroid ,Ultrasonography, Doppler, Color ,Inferior thyroid artery ,Autoimmune disease ,business.industry ,Thyroid ,Ultrasound ,Thyroiditis, Autoimmune ,Blood flow ,medicine.disease ,Graves Disease ,medicine.anatomical_structure ,Regional Blood Flow ,Female ,business - Abstract
Thyroid hypoechogenicity at ultrasound is a characteristic of autoimmune thyroid diseases, with an overlap of this echographic pattern in patients affected by Graves' disease or Hashimoto's thyroiditis. Aim of the present paper was to study the thyroid blood flow (TBF) by color-flow doppler (CFD) and peak systolic velocity (PSV) at the inferior thyroid artery in 37 Graves' and 45 goitrous Hashimoto's thyroiditis patients. CFD pattern was defined as normal (or type 0): TBF limited to peripheral thyroid arteries (PSV = 17.7 +/- 3 cm/sec, mean +/- SD); type I: TBF mildly increased; type II: TBF clearly increased; type III: TBF markedly increased. The CFD was in direct relationship to the PSV. Out of 18 patients with Graves' disease and untreated active hyperthyroidism CFD pattern was type III in 17 and type II in 1. The PSV was 42.1 +/- 15 cm/sec. In 17 patients euthyroid under methimazole, the CFD pattern was type 0 in 3 (17%) type I in 5 (30%), type II in 5 (30%), type III in 4 (23%). In this group of Graves' patients the PSV was 36 +/- 14 cm/sec. In two patients, hypothyroid after radioiodine treatment, the CFD pattern was type 0 in 1 and type I in 1. In the group of Hashimoto's patients TBF was in no relationship with thyroid status or treatment and was type 0 in 22 (49%), type I in 20 (44%), type II in 3 (7%), while none had type III CFD pattern. Thyroid hypoechogenicity at ultrasound was present in 32/37 (86%) Graves' and 41/45 (91%) Hashimoto's patients. All the four patients with Hashimoto's thyroiditis and normal thyroid ultrasound pattern had also a normal CFD pattern, while 4/5 patients with Graves' disease and normal echographic pattern had an increased TBF. In conclusion, a diffusely increased thyroid blood flow is pathognomonic of untreated Graves' disease and an abnormal CFD pattern identifies the majority of Graves' patients with a normal thyroid ultrasound pattern. Thus, CFD sonography may be useful in distinguishing patients with Graves' disease and Hashimoto's thyroiditis having a similar thyroid echographic pattern at ultrasound.
- Published
- 1995
26. ULTRASONOGRAPHY OF GASTROINTESTINAL TRACT DISORDERS: RETROSPECTIVE AND PROSPECTIVE EVALUATION
- Author
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A. De Liperi, L Pieri, C. Bartolozzi, Davide Caramella, F. Sanguinetti, M. Bimbi, R Russo, Salvatore Mazzeo, Fabio Pinto, and Riccardo Lencioni
- Subjects
medicine.medical_specialty ,Gastrointestinal tract ,medicine.diagnostic_test ,business.industry ,Interventional radiology ,General Medicine ,Disease ,Gastroenterology ,Gastrointestinal tract disorders ,Radiological weapon ,Internal medicine ,parasitic diseases ,medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Abnormality ,Ultrasonography ,business ,Neuroradiology - Abstract
In a retrospective analysis performed on 4167 routine abdominal sonographic (US) examinations (September 1989 to December 1991), 93 US reports strongly suggesting the presence of gastrointestinal (GI) tract disorders were found. Neoplastic GI tract diseases were indicated in 65.6 % of cases and non-neoplastic conditions in 34.4 %. The final diagnoses confirmed all the cases of non-neoplastic disease, while 3 patients sonographically suspected as having a neoplasm proved not to have any GI tract abnormality. In the period January 1992 to December 1992, 62 patients with a suspected GI tract abnormality were enrolled in a prospective double-masked US study after being submitted to conventional radiological studies only in 28 of 62 cases, after conventional studies and CT in 24 of 62 cases, and after CT only in 10 of 62 cases. Sonography furnished additional diagnostic information in 28 of 62 cases when the previous radiological examination did not include CT, but sonography misinterpreted 4 inflammatory disorders as tumours. Our study confirmed the important role of US alone or in association with other imaging modalities in the study of GI tract diseases.
- Published
- 1995
27. Transmission of radiological images using broadband communications
- Author
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Riccardo Lencioni, Davide Caramella, Salvatore Mazzeo, and C. Bartolozzi
- Subjects
medicine.medical_specialty ,business.industry ,Real-time computing ,General Medicine ,Teleradiology ,Broadband communication ,Field (computer science) ,Transmission (telecommunications) ,Image transfer ,Radiological weapon ,Broadband ,medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Information flow (information theory) ,business - Abstract
The aim of our work was to implement and validate a system for the acquisition, local management and remote transmission of diagnostic images using two interconnected brrnldbarud Metropolitan Area Networks (MANs). The MAN technoloy is compliant with the IEEE 8()2.6 standard, also known as DiStribrutell Queue Dual Bus (D()1)B). Application domains included tcleradiblogy and teleprocessing of diagnostic incages. Teleradiology was focused on the enhancement of the radiologist to clinician information flow witlcirc the framework of the European Project EurIPACS. An intrainstitutional scenario was taken as a paradigm in the field of staging, nonstrrgical treatment, and follow-up of hepatocellular carcinoma. Remote processing of diagnostic images using the broadband MAN allowed a cooperative work with scientific institutions in an area often limited by the complexity of image transfer acrd the lack of timely feedback concerning tlce. clinical usefulness of processed images. ()ur preliminary experience demonstrated that the DQDB MAN provided a fast and reliable means for transmitting diagnostic images.
- Published
- 1994
28. Percutaneous injection of ethanol to treat autonomous thyroid nodules
- Author
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Salvatore Mazzeo, Davide Caramella, Riccardo Lencioni, C De Gaudio, F. Sanguinetti, M. G. Toni, C. Bartolozzi, and Fabio Pinto
- Subjects
Adult ,Male ,Thyroid nodules ,medicine.medical_specialty ,Percutaneous ,Ethanol ,medicine.diagnostic_test ,business.industry ,Nodule (medicine) ,General Medicine ,Middle Aged ,Scintigraphy ,medicine.disease ,Injections ,Surgery ,medicine ,Humans ,Female ,Radiology, Nuclear Medicine and imaging ,Thyroid Nodule ,medicine.symptom ,business ,Aged ,Ultrasonography - Abstract
The aim of this study was to evaluate the efficacy and safety of sonographically guided percutaneous injection of ethanol for treating autonomous thyroid nodules in order to assess that technique's feasibility as an alternative to traditional ablative (radionuclide and surgical) therapies.Thirty-two patients with autonomous thyroid nodules were included in the study: seven had thyrotoxicosis, and 25 were in the pretoxic clinical phase. Ethanol was injected percutaneously on an outpatient basis once or twice a week for a total of three to 10 injections per nodule, mainly depending on the nodule's size. Scintigrams obtained 3 months after the end of treatment were used to assess response to this therapy. The follow-up period was from 3 to 30 months.Thyroid scintigraphy 3 months after percutaneous injection of ethanol showed complete recovery of function in extranodular tissue in 26 patients (81%), partial recovery in five patients (16%), and no recovery in one patient (3%). In all patients, the volume of the nodules decreased by more than 50% after treatment. In three of five patients in whom scintigraphy showed only partial recovery of function in extranodular tissue, a second percutaneous injection of ethanol was given after 15 months. The therapy was well tolerated, and after a total of 216 injections, no patient had permanent side effects.Our experience shows that percutaneous injection of ethanol is a practical alternative to traditional treatments for autonomous thyroid nodules and that it is an option for treating pretoxic adenoma.
- Published
- 1993
29. Sonographic volume processing of malignant prostatic lesions
- Author
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G Braccini, C. Bartolozzi, Davide Caramella, L Battolla, O. Salvetti, and F Cartei
- Subjects
Prostate adenocarcinoma ,Radiation therapy ,medicine.medical_specialty ,business.industry ,malignant prostatic lesions ,medicine.medical_treatment ,3D reconstruction ,Sonographic ,medicine ,volume processing ,Radiology ,business ,Volume (compression) - Abstract
The aim of this study was to investigate the possibility of a precise definition of the volumetric and spatial features of malignant prostatic lesions needing radiation therapy and a later follow-up. The modeling procedure is mainly composed of three sequential phases: a) automatic acquisition of time sequences of 2D echotomograms; b) 3D reconstruction of images; c) generation of a spatial geometrical model. A software system has been specifically designed and implemented for digital image handling and management. The preliminary c1inical applications in the evaluation of patients with prostatic cancer showed promising results.
- Published
- 1991
30. E - Authors’ Index
- Author
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F Turini, Eugenia Picano, L Faggioni, Paola Vagli, C. Bartolozzi, Emanuele Neri, and F Cerri
- Subjects
Multimedia ,Computer science ,Computer graphics (images) ,Reading (process) ,media_common.quotation_subject ,Color-coding ,Radiology, Nuclear Medicine and imaging ,Open source software ,computer.software_genre ,computer ,Article ,media_common - Abstract
Poster: "ECR 2010 / B-828 / CT colonography with color coding by means of open source software (OsiriX): A new approach to primary 2D reading " by: " L. Faggioni , E. Neri, F. Cerri, F. Turini, E. Picano, P. Vagli, C. Bartolozzi; Pisa/IT"
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31. Arteriovenous fistula associated with renal cell carcinoma: demonstration by magnetic resonance imaging
- Author
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C. Bartolozzi, Cesare Selli, D. Petacchi, and G Lizzadro
- Subjects
Adult ,Male ,medicine.medical_specialty ,Kidney ,Magnetic Resonance Spectroscopy ,medicine.diagnostic_test ,business.industry ,Urology ,Arteriovenous fistula ,Magnetic resonance imaging ,medicine.disease ,Kidney Neoplasms ,Renal Veins ,Arteriovenous Malformations ,Text mining ,medicine.anatomical_structure ,Renal Artery ,Renal cell carcinoma ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Female ,Radiology ,business ,Carcinoma, Renal Cell - Abstract
Two cases of arteriovenous fistula associated with renal cell carcinoma were studied using multiple techniques, including magnetic resonance imaging (MR). These techniques clearly delineated the vascular abnormalities without the use of a contrast agent; they also demonstrated the extent of the tumors. Data derived from MR were confirmed upon surgical exploration and were useful in planning the approach to the kidney.
- Published
- 1986
32. Neuromorphic computing at scale.
- Author
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Kudithipudi D, Schuman C, Vineyard CM, Pandit T, Merkel C, Kubendran R, Aimone JB, Orchard G, Mayr C, Benosman R, Hays J, Young C, Bartolozzi C, Majumdar A, Cardwell SG, Payvand M, Buckley S, Kulkarni S, Gonzalez HA, Cauwenberghs G, Thakur CS, Subramoney A, and Furber S
- Subjects
- Humans, Brain physiology, Computers, Neural Networks, Computer, Algorithms
- Abstract
Neuromorphic computing is a brain-inspired approach to hardware and algorithm design that efficiently realizes artificial neural networks. Neuromorphic designers apply the principles of biointelligence discovered by neuroscientists to design efficient computational systems, often for applications with size, weight and power constraints. With this research field at a critical juncture, it is crucial to chart the course for the development of future large-scale neuromorphic systems. We describe approaches for creating scalable neuromorphic architectures and identify key features. We discuss potential applications that can benefit from scaling and the main challenges that need to be addressed. Furthermore, we examine a comprehensive ecosystem necessary to sustain growth and the new opportunities that lie ahead when scaling neuromorphic systems. Our work distils ideas from several computing sub-fields, providing guidance to researchers and practitioners of neuromorphic computing who aim to push the frontier forward., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. Springer Nature Limited.)
- Published
- 2025
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33. Arm muscle synergies enhance hand posture prediction in combination with forearm muscle synergies.
- Author
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Tanzarella S, Di Domenico D, Forsiuk I, Boccardo N, Chiappalone M, Bartolozzi C, and Semprini M
- Subjects
- Humans, Electromyography methods, Muscle, Skeletal physiology, Hand physiology, Posture physiology, Forearm, Arm physiology
- Abstract
Objective. We analyze and interpret arm and forearm muscle activity in relation with the kinematics of hand pre-shaping during reaching and grasping from the perspective of human synergistic motor control. Approach. Ten subjects performed six tasks involving reaching, grasping and object manipulation. We recorded electromyographic (EMG) signals from arm and forearm muscles with a mix of bipolar electrodes and high-density grids of electrodes. Motion capture was concurrently recorded to estimate hand kinematics. Muscle synergies were extracted separately for arm and forearm muscles, and postural synergies were extracted from hand joint angles. We assessed whether activation coefficients of postural synergies positively correlate with and can be regressed from activation coefficients of muscle synergies. Each type of synergies was clustered across subjects. Main results. We found consistency of the identified synergies across subjects, and we functionally evaluated synergy clusters computed across subjects to identify synergies representative of all subjects. We found a positive correlation between pairs of activation coefficients of muscle and postural synergies with important functional implications. We demonstrated a significant positive contribution in the combination between arm and forearm muscle synergies in estimating hand postural synergies with respect to estimation based on muscle synergies of only one body segment, either arm or forearm ( p < 0.01). We found that dimensionality reduction of multi-muscle EMG root mean square (RMS) signals did not significantly affect hand posture estimation, as demonstrated by comparable results with regression of hand angles from EMG RMS signals. Significance. We demonstrated that hand posture prediction improves by combining activity of arm and forearm muscles and we evaluate, for the first time, correlation and regression between activation coefficients of arm muscle and hand postural synergies. Our findings can be beneficial for myoelectric control of hand prosthesis and upper-limb exoskeletons, and for biomarker evaluation during neurorehabilitation., (Creative Commons Attribution license.)
- Published
- 2024
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34. Insights into Batch Selection for Event-Camera Motion Estimation.
- Author
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Valerdi JL, Bartolozzi C, and Glover A
- Abstract
Event cameras measure scene changes with high temporal resolutions, making them well-suited for visual motion estimation. The activation of pixels results in an asynchronous stream of digital data (events), which rolls continuously over time without the discrete temporal boundaries typical of frame-based cameras (where a data packet or frame is emitted at a fixed temporal rate). As such, it is not trivial to define a priori how to group/accumulate events in a way that is sufficient for computation. The suitable number of events can greatly vary for different environments, motion patterns, and tasks. In this paper, we use neural networks for rotational motion estimation as a scenario to investigate the appropriate selection of event batches to populate input tensors. Our results show that batch selection has a large impact on the results: training should be performed on a wide variety of different batches, regardless of the batch selection method; a simple fixed-time window is a good choice for inference with respect to fixed-count batches, and it also demonstrates comparable performance to more complex methods. Our initial hypothesis that a minimal amount of events is required to estimate motion (as in contrast maximization) is not valid when estimating motion with a neural network.
- Published
- 2023
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35. Neuromorphic Decoding of Spinal Motor Neuron Behaviour During Natural Hand Movements for a New Generation of Wearable Neural Interfaces.
- Author
-
Tanzarella S, Iacono M, Donati E, Farina D, and Bartolozzi C
- Subjects
- Humans, Neural Networks, Computer, Hand, Recognition, Psychology, Motor Neurons physiology, Wearable Electronic Devices
- Abstract
We propose a neuromorphic framework to process the activity of human spinal motor neurons for movement intention recognition. This framework is integrated into a non-invasive interface that decodes the activity of motor neurons innervating intrinsic and extrinsic hand muscles. One of the main limitations of current neural interfaces is that machine learning models cannot exploit the efficiency of the spike encoding operated by the nervous system. Spiking-based pattern recognition would detect the spatio-temporal sparse activity of a neuronal pool and lead to adaptive and compact implementations, eventually running locally in embedded systems. Emergent Spiking Neural Networks (SNN) have not yet been used for processing the activity of in-vivo human neurons. Here we developed a convolutional SNN to process a total of 467 spinal motor neurons whose activity was identified in 5 participants while executing 10 hand movements. The classification accuracy approached 0.95 ±0.14 for both isometric and non-isometric contractions. These results show for the first time the potential of highly accurate motion intent detection by combining non-invasive neural interfaces and SNN.
- Published
- 2023
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- View/download PDF
36. luvHarris: A Practical Corner Detector for Event-Cameras.
- Author
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Glover A, Dinale A, Rosa LS, Bamford S, and Bartolozzi C
- Abstract
There have been a number of corner detection methods proposed for event cameras in the last years, since event-driven computer vision has become more accessible. Current state-of-the-art have either unsatisfactory accuracy or real-time performance when considered for practical use, for example when a camera is randomly moved in an unconstrained environment. In this paper, we present yet another method to perform corner detection, dubbed look-up event-Harris (luvHarris), that employs the Harris algorithm for high accuracy but manages an improved event throughput. Our method has two major contributions, 1. a novel "threshold ordinal event-surface" that removes certain tuning parameters and is well suited for Harris operations, and 2. an implementation of the Harris algorithm such that the computational load per event is minimised and computational heavy convolutions are performed only 'as-fast-as-possible', i.e., only as computational resources are available. The result is a practical, real-time, and robust corner detector that runs more than 2.6× the speed of current state-of-the-art; a necessity when using a high-resolution event-camera in real-time. We explain the considerations taken for the approach, compare the algorithm to current state-of-the-art in terms of computational performance and detection accuracy, and discuss the validity of the proposed approach for event cameras.
- Published
- 2022
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37. Braille letter reading: A benchmark for spatio-temporal pattern recognition on neuromorphic hardware.
- Author
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Müller-Cleve SF, Fra V, Khacef L, Pequeño-Zurro A, Klepatsch D, Forno E, Ivanovich DG, Rastogi S, Urgese G, Zenke F, and Bartolozzi C
- Abstract
Spatio-temporal pattern recognition is a fundamental ability of the brain which is required for numerous real-world activities. Recent deep learning approaches have reached outstanding accuracies in such tasks, but their implementation on conventional embedded solutions is still very computationally and energy expensive. Tactile sensing in robotic applications is a representative example where real-time processing and energy efficiency are required. Following a brain-inspired computing approach, we propose a new benchmark for spatio-temporal tactile pattern recognition at the edge through Braille letter reading. We recorded a new Braille letters dataset based on the capacitive tactile sensors of the iCub robot's fingertip. We then investigated the importance of spatial and temporal information as well as the impact of event-based encoding on spike-based computation. Afterward, we trained and compared feedforward and recurrent Spiking Neural Networks (SNNs) offline using Backpropagation Through Time (BPTT) with surrogate gradients, then we deployed them on the Intel Loihi neuromorphic chip for fast and efficient inference. We compared our approach to standard classifiers, in particular to the Long Short-Term Memory (LSTM) deployed on the embedded NVIDIA Jetson GPU, in terms of classification accuracy, power, and energy consumption together with computational delay. Our results show that the LSTM reaches ~97% of accuracy, outperforming the recurrent SNN by ~17% when using continuous frame-based data instead of event-based inputs. However, the recurrent SNN on Loihi with event-based inputs is ~500 times more energy-efficient than the LSTM on Jetson, requiring a total power of only ~30 mW. This work proposes a new benchmark for tactile sensing and highlights the challenges and opportunities of event-based encoding, neuromorphic hardware, and spike-based computing for spatio-temporal pattern recognition at the edge., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Müller-Cleve, Fra, Khacef, Pequeño-Zurro, Klepatsch, Forno, Ivanovich, Rastogi, Urgese, Zenke and Bartolozzi.)
- Published
- 2022
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38. The comet assay for the evaluation of gut content genotoxicity: Use in human studies as an early biomarker of colon cancer risk.
- Author
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Ristori S, Scavone F, Bartolozzi C, and Giovannelli L
- Subjects
- Animals, Biomarkers, Comet Assay, Humans, Water, Colonic Neoplasms genetics
- Abstract
This short narrative review describes the use of the comet assay to evaluate the formation of genotoxic compounds in the gut lumen in human studies. The fecal water genotoxicity assay is based on ability of the gut content to induce genotoxicity in a cellular model, employing the aqueous component of the feces (fecal water) as this is supposed to contain most of the reactive species and to convey them to the intestinal epithelium. This non-invasive and low-cost assay has been demonstrated to be associated with colon cancer risk in animal models, and although the final validation against human tumors is lacking, it is widely used as a colo-rectal cancer risk biomarker in human nutritional intervention studies. The contribution given to the field of nutrition and cancer by the FW genotoxicity assay is highlighted, particularly in conjunction with other risk biomarkers, to shed light on the complex relationship among diet, microbiota, individual subject characteristics and the formation of genotoxic compounds in the gut., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
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39. Event-driven proto-object based saliency in 3D space to attract a robot's attention.
- Author
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Ghosh S, D'Angelo G, Glover A, Iacono M, Niebur E, and Bartolozzi C
- Subjects
- Humans, Motion, Robotics
- Abstract
To interact with its environment, a robot working in 3D space needs to organise its visual input in terms of objects or their perceptual precursors, proto-objects. Among other visual cues, depth is a submodality used to direct attention to visual features and objects. Current depth-based proto-object attention models have been implemented for standard RGB-D cameras that produce synchronous frames. In contrast, event cameras are neuromorphic sensors that loosely mimic the function of the human retina by asynchronously encoding per-pixel brightness changes at very high temporal resolution, thereby providing advantages like high dynamic range, efficiency (thanks to their high degree of signal compression), and low latency. We propose a bio-inspired bottom-up attention model that exploits event-driven sensing to generate depth-based saliency maps that allow a robot to interact with complex visual input. We use event-cameras mounted in the eyes of the iCub humanoid robot to directly extract edge, disparity and motion information. Real-world experiments demonstrate that our system robustly selects salient objects near the robot in the presence of clutter and dynamic scene changes, for the benefit of downstream applications like object segmentation, tracking and robot interaction with external objects., (© 2022. The Author(s).)
- Published
- 2022
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40. Author Correction: Embodied neuromorphic intelligence.
- Author
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Bartolozzi C, Indiveri G, and Donati E
- Published
- 2022
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41. Embodied neuromorphic intelligence.
- Author
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Bartolozzi C, Indiveri G, and Donati E
- Subjects
- Engineering, Intelligence, Neural Networks, Computer
- Abstract
The design of robots that interact autonomously with the environment and exhibit complex behaviours is an open challenge that can benefit from understanding what makes living beings fit to act in the world. Neuromorphic engineering studies neural computational principles to develop technologies that can provide a computing substrate for building compact and low-power processing systems. We discuss why endowing robots with neuromorphic technologies - from perception to motor control - represents a promising approach for the creation of robots which can seamlessly integrate in society. We present initial attempts in this direction, highlight open challenges, and propose actions required to overcome current limitations., (© 2022. The Author(s).)
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- 2022
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42. Rotational thromboelastometry for diagnosis of fibrinolysis induced by urokinase in an in-vitro model.
- Author
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Bevilacqua S, Paniccia R, Galeotti I, Viappiani A, Dimizio F, Bartolozzi C, Marcucci R, and Stefàno P
- Subjects
- Blood Coagulation, Fibrin Clot Lysis Time, Fibrinolysis, Humans, Thrombelastography, Urokinase-Type Plasminogen Activator
- Abstract
Fibrinolysis can be abnormally activated in several critical care settings but it's often misdiagnosed by standard laboratory tests. Although rotational thromboelastometry can assess the whole coagulative process, its ability to detect fibrinolysis has been questioned. Aim of this study was to investigate the ability of thromboelastometry in detecting induced fibrinolysis in an in-vitro model. Whole blood samples were taken from 18 healthy volunteers. Each sample was split and added with increasing urokinase concentrations till to reach 0, 50, 75 and 100 IU/ml. Thromboelastometry tests, extem and aptem, were performed on the obtained samples. If significant lysis at 50 IU/ml was recorded, also 10, 25 and 35 IU/ml drug concentrations were tested. No lytic effects were detected in 10 IU/ml samples. Lysis variables were the most sensitive in detecting fibrinolysis even at 25 IU/ml (P < 0.05). Clot firmness parameters were also affected by urokinase, but only at the two highest drug concentrations (P < 0.05). Extem/aptem ratio enhanced the sensitivity of these parameters only if lysis was more marked. Analysing groups of different lysis severity, the time to achieve maximum clot firmness could anticipate an ongoing fulminant or intermediate lysis with 100% sensitivity and 100% specificity (P < 0.05) when lower than 1341.5 s. Rotational thromboelastometry could detect fibrinolysis when it was induced in vitro by 25 IU/ml urokinase or more. Apart from the parameters specific for lysis, time to achieve maximum clot firmness appeared as the earliest indicator of fibrinolysis with high sensitivity and specificity especially if a more intense lysis was going on., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2022
- Full Text
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43. Event-Based Vision: A Survey.
- Author
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Gallego G, Delbruck T, Orchard G, Bartolozzi C, Taba B, Censi A, Leutenegger S, Davison AJ, Conradt J, Daniilidis K, and Scaramuzza D
- Subjects
- Neural Networks, Computer, Algorithms, Robotics
- Abstract
Event cameras are bio-inspired sensors that differ from conventional frame cameras: Instead of capturing images at a fixed rate, they asynchronously measure per-pixel brightness changes, and output a stream of events that encode the time, location and sign of the brightness changes. Event cameras offer attractive properties compared to traditional cameras: high temporal resolution (in the order of μs), very high dynamic range (140 dB versus 60 dB), low power consumption, and high pixel bandwidth (on the order of kHz) resulting in reduced motion blur. Hence, event cameras have a large potential for robotics and computer vision in challenging scenarios for traditional cameras, such as low-latency, high speed, and high dynamic range. However, novel methods are required to process the unconventional output of these sensors in order to unlock their potential. This paper provides a comprehensive overview of the emerging field of event-based vision, with a focus on the applications and the algorithms developed to unlock the outstanding properties of event cameras. We present event cameras from their working principle, the actual sensors that are available and the tasks that they have been used for, from low-level vision (feature detection and tracking, optic flow, etc.) to high-level vision (reconstruction, segmentation, recognition). We also discuss the techniques developed to process events, including learning-based techniques, as well as specialized processors for these novel sensors, such as spiking neural networks. Additionally, we highlight the challenges that remain to be tackled and the opportunities that lie ahead in the search for a more efficient, bio-inspired way for machines to perceive and interact with the world.
- Published
- 2022
- Full Text
- View/download PDF
44. Face Pose Alignment with Event Cameras.
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Savran A and Bartolozzi C
- Subjects
- Data Analysis, Head Movements, Humans, Photography, Face, Head
- Abstract
Event camera (EC) emerges as a bio-inspired sensor which can be an alternative or complementary vision modality with the benefits of energy efficiency, high dynamic range, and high temporal resolution coupled with activity dependent sparse sensing. In this study we investigate with ECs the problem of face pose alignment, which is an essential pre-processing stage for facial processing pipelines. EC-based alignment can unlock all these benefits in facial applications, especially where motion and dynamics carry the most relevant information due to the temporal change event sensing. We specifically aim at efficient processing by developing a coarse alignment method to handle large pose variations in facial applications. For this purpose, we have prepared by multiple human annotations a dataset of extreme head rotations with varying motion intensity. We propose a motion detection based alignment approach in order to generate activity dependent pose-events that prevents unnecessary computations in the absence of pose change. The alignment is realized by cascaded regression of extremely randomized trees. Since EC sensors perform temporal differentiation, we characterize the performance of the alignment in terms of different levels of head movement speeds and face localization uncertainty ranges as well as face resolution and predictor complexity. Our method obtained 2.7% alignment failure on average, whereas annotator disagreement was 1%. The promising coarse alignment performance on EC sensor data together with a comprehensive analysis demonstrate the potential of ECs in facial applications.
- Published
- 2020
- Full Text
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45. Self healable neuromorphic memtransistor elements for decentralized sensory signal processing in robotics.
- Author
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John RA, Tiwari N, Patdillah MIB, Kulkarni MR, Tiwari N, Basu J, Bose SK, Ankit, Yu CJ, Nirmal A, Vishwanath SK, Bartolozzi C, Basu A, and Mathews N
- Subjects
- Action Potentials physiology, Logic, Neuronal Plasticity physiology, Nociception, Presynaptic Terminals physiology, Robotics, Signal Processing, Computer-Assisted, Transistors, Electronic
- Abstract
Sensory information processing in robot skins currently rely on a centralized approach where signal transduction (on the body) is separated from centralized computation and decision-making, requiring the transfer of large amounts of data from periphery to central processors, at the cost of wiring, latency, fault tolerance and robustness. We envision a decentralized approach where intelligence is embedded in the sensing nodes, using a unique neuromorphic methodology to extract relevant information in robotic skins. Here we specifically address pain perception and the association of nociception with tactile perception to trigger the escape reflex in a sensorized robotic arm. The proposed system comprises self-healable materials and memtransistors as enabling technologies for the implementation of neuromorphic nociceptors, spiking local associative learning and communication. Configuring memtransistors as gated-threshold and -memristive switches, the demonstrated system features in-memory edge computing with minimal hardware circuitry and wiring, and enhanced fault tolerance and robustness.
- Published
- 2020
- Full Text
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46. An On-chip Spiking Neural Network for Estimation of the Head Pose of the iCub Robot.
- Author
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Kreiser R, Renner A, Leite VRC, Serhan B, Bartolozzi C, Glover A, and Sandamirskaya Y
- Abstract
In this work, we present a neuromorphic architecture for head pose estimation and scene representation for the humanoid iCub robot. The spiking neuronal network is fully realized in Intel's neuromorphic research chip, Loihi, and precisely integrates the issued motor commands to estimate the iCub's head pose in a neuronal path-integration process. The neuromorphic vision system of the iCub is used to correct for drift in the pose estimation. Positions of objects in front of the robot are memorized using on-chip synaptic plasticity. We present real-time robotic experiments using 2 degrees of freedom (DoF) of the robot's head and show precise path integration, visual reset, and object position learning on-chip. We discuss the requirements for integrating the robotic system and neuromorphic hardware with current technologies., (Copyright © 2020 Kreiser, Renner, Leite, Serhan, Bartolozzi, Glover and Sandamirskaya.)
- Published
- 2020
- Full Text
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47. Event-Based Eccentric Motion Detection Exploiting Time Difference Encoding.
- Author
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D'Angelo G, Janotte E, Schoepe T, O'Keeffe J, Milde MB, Chicca E, and Bartolozzi C
- Abstract
Attentional selectivity tends to follow events considered as interesting stimuli. Indeed, the motion of visual stimuli present in the environment attract our attention and allow us to react and interact with our surroundings. Extracting relevant motion information from the environment presents a challenge with regards to the high information content of the visual input. In this work we propose a novel integration between an eccentric down-sampling of the visual field, taking inspiration from the varying size of receptive fields (RFs) in the mammalian retina, and the Spiking Elementary Motion Detector (sEMD) model. We characterize the system functionality with simulated data and real world data collected with bio-inspired event driven cameras, successfully implementing motion detection along the four cardinal directions and diagonally., (Copyright © 2020 D'Angelo, Janotte, Schoepe, O'Keeffe, Milde, Chicca and Bartolozzi.)
- Published
- 2020
- Full Text
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48. Alexithymia Predicts Carotid Atherosclerosis, Vascular Events, and All-Cause Mortality in Human Immunodeficiency Virus-Infected Patients: An Italian Multisite Prospective Cohort Study.
- Author
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Vadini F, Sozio F, Madeddu G, De Socio G, Maggi P, Nunnari G, Vichi F, Di Stefano P, Tracanna E, Polilli E, Sciacca A, Zizi B, Lai V, Bartolozzi C, Flacco ME, Bonfanti P, Santilli F, Manzoli L, and Parruti G
- Abstract
Background: Psychological factors (PFs) are known predictors of cardiovascular disease (CVD) in many clinical settings, but data are lacking for human immunodeficiency virus (HIV) infection. We carried out a prospective study to evaluate (1) psychological predictors of preclinical and clinical vascular disease and (2) all-cause mortality (ACM) in HIV patients., Methods: We conducted a cross-sectional analysis of baseline data to evaluate the predictors of carotid plaques (CPs) and a prospective analysis to explore predictors of vascular events (VEs) and ACM over 10 years. Human immunodeficiency virus patients monitored at the Infectious Disease Units of 6 Italian regions were consecutively enrolled. Traditional CVD risk factors, PFs (depressive symptoms, alexithymia, distress personality), and CPs were investigated. Vascular events and ACM after enrollment were censored at March 2018., Results: A multicenter cohort of 712 HIV-positive patients (75.3% males, aged 46.1 ± 10.1 years) was recruited. One hundred seventy-five (31.6%) patients had CPs at baseline. At the cross-sectional analysis, alexithymia was independently associated with CPs (odds ratio, 4.93; 95% confidence interval [CI], 2.90-8.50; P < .001), after adjustment for sociodemographic, clinical, and psychological variables. After an average follow-up of 4.4 ± 2.4 years, 54 (7.6%) patients developed a VE, whereas 41 (5.68%) died. Age, current smoking, hypertension, and alexithymia (hazard ratio [HR], 3.66; 95% CI, 1.80-7.44; P < .001) were independent predictors of VE. Likewise, alexithymia was an independent predictor of ACM (HR, 3.93; 95% CI, 1.65-9.0; P = .002), regardless of other clinical predictors., Conclusions: The present results validate our previous monocentric finding. Alexithymia may be an additional tool for the multifactorial assessment of cardiovascular risk in HIV., (© The Author(s) 2019. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)
- Published
- 2019
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49. Blood flow maintenance by cardiac massage during cardiopulmonary resuscitation: Classical theories, newer hypotheses, and clinical utility of mechanical devices.
- Author
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Cipani S, Bartolozzi C, Ballo P, and Sarti A
- Abstract
The mechanisms by which closed chest cardiac massage produces and maintains blood flow during cardiopulmonary resuscitation are still debated. To date, two main theories exist: the "cardiac pump", which assumes that blood flow is driven by direct cardiac compression and the "chest pump", which hypothesizes that blood flow is caused by changes in intrathoracic pressure. Newer hypotheses including the "atrial pump", the "lung pump", and the "respiratory pump" were also proposed. We reviewed studies supporting these different theories as well as the clinical evidences on the utility of mechanical devices proposed to optimize cardiopulmonary resuscitation, in view of their pathophysiological assumptions with regard to the underlying theory. On the basis of current evidence, a single theory is probably not sufficient to explain how cardiac massage produces blood flow. This suggests that different simultaneous mechanism might be involved. The relative importance of these mechanisms depends on several factors, including delay from collapse to starting of resuscitation, compression force and rate, body habitus, airway pressure, and presenting electrocardiogram. The complexity of the physiologic events occurring during cardiopulmonary resuscitation, together with the need of adequate training for a correct and prompt utilization of mechanical devices, might also partially explain the disappointing results of these devices in most clinical studies.
- Published
- 2019
- Full Text
- View/download PDF
50. Neuromorphic circuits impart a sense of touch.
- Author
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Bartolozzi C
- Subjects
- Synapses, Models, Neurological, Touch
- Published
- 2018
- Full Text
- View/download PDF
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