4,199 research outputs found
An Interpretable Deep Hierarchical Semantic Convolutional Neural Network for Lung Nodule Malignancy Classification
While deep learning methods are increasingly being applied to tasks such as
computer-aided diagnosis, these models are difficult to interpret, do not
incorporate prior domain knowledge, and are often considered as a "black-box."
The lack of model interpretability hinders them from being fully understood by
target users such as radiologists. In this paper, we present a novel
interpretable deep hierarchical semantic convolutional neural network (HSCNN)
to predict whether a given pulmonary nodule observed on a computed tomography
(CT) scan is malignant. Our network provides two levels of output: 1) low-level
radiologist semantic features, and 2) a high-level malignancy prediction score.
The low-level semantic outputs quantify the diagnostic features used by
radiologists and serve to explain how the model interprets the images in an
expert-driven manner. The information from these low-level tasks, along with
the representations learned by the convolutional layers, are then combined and
used to infer the high-level task of predicting nodule malignancy. This unified
architecture is trained by optimizing a global loss function including both
low- and high-level tasks, thereby learning all the parameters within a joint
framework. Our experimental results using the Lung Image Database Consortium
(LIDC) show that the proposed method not only produces interpretable lung
cancer predictions but also achieves significantly better results compared to
common 3D CNN approaches
Automatic Workflow for Narrow-Band Laryngeal Video Stitching
In narrow band (NB) laryngeal endoscopy, the clinician usually positions the endoscope near the tissue for a correct inspection of possible vascular pattern alterations, indicative of laryngeal malignancies. The video is usually reviewed many times to refine the diagnosis, resulting in loss of time since the salient frames of the video are mixed with blurred, noisy, and redundant frames caused by the endoscope movements. The aim of this work is to provide to the clinician a unique larynx panorama, obtained through an automatic frame selection strategy to discard non-informative frames. Anisotropic diffusion filtering was exploited to lower the noise level while encouraging the selection of meaningful image features, and a feature-based stitching approach was carried out to generate the panorama. The frame selection strategy, tested on on six pathological NB endoscopic videos, was compared with standard strategies, as uniform and random sampling, showing higher performance of the subsequent stitching procedure, both visually, in terms of vascular structure preservation, and numerically, through a blur estimation metric
Comparative ergonomic workflow and user experience analysis of MRI versus fluoroscopy-guided vascular interventions:an iliac angioplasty exemplar case study
Purpose A methodological framework is introduced to assess and compare a conventional fluoroscopy protocol for peripheral angioplasty with a new magnetic resonant imaging (MRI)-guided protocol. Different scenarios were considered during interventions on a perfused arterial phantom with regard to time-based and cognitive task analysis, user experience and ergonomics. Methods Three clinicians with different expertise performed a total of 43 simulated common iliac angioplasties (9 fluoroscopic, 34 MRI-guided) in two blocks of sessions. Six different configurations for MRI guidance were tested in the first block. Four of them were evaluated in the second block and compared to the fluoroscopy protocol. Relevant stages’ durations were collected, and interventions were audio-visually recorded from different perspectives. A cued retrospective protocol analysis (CRPA) was undertaken, including personal interviews. In addition, ergonomic constraints in the MRI suite were evaluated. Results Significant differences were found when comparing the performance between MRI configurations versus fluoroscopy. Two configurations [with times of 8.56 (0.64) and 9.48 (1.13) min] led to reduce procedure time for MRI guidance, comparable to fluoroscopy [8.49 (0.75) min]. The CRPA pointed out the main influential factors for clinical procedure performance. The ergonomic analysis quantified musculoskeletal risks for interventional radiologists when utilising MRI. Several alternatives were suggested to prevent potential low-back injuries. Conclusions This work presents a step towards the implementation of efficient operational protocols for MRI-guided procedures based on an integral and multidisciplinary framework, applicable to the assessment of current vascular protocols. The use of first-user perspective raises the possibility of establishing new forms of clinical training and education
Focal Spot, Spring/Summer 1985
https://digitalcommons.wustl.edu/focal_spot_archives/1040/thumbnail.jp
Parametric and Visual Programming BIM Applied to Museums, Linking Container and Content
In recent years we have been experiencing an ever-increasing number of Building Modeling Modeling (BIM) and Visual Programming Language (VPL) approaches in the architectural design field. These experiments have inspired new research strictly focused on exploring values, criticalities, and the advantages of applying these combined methodologies in the Cultural Heritage domain. This integrated approach has emphasized the benefits derived from HBIM. The next step is to critically evaluate the application of BIM and VPL processes used in the management and valorisation of museum heritage, pursuing both parametric and algorithmic approaches. The research group worked on building a model that shared the BIM hierarchical structure and the flexibility of the VPL methodologies. Semi-automatic procedures were developed within a rigorous BIM workflow, with the help of Autodesk and McNeel tools, to show and manage complex museum management phenomena. These procedures aimed to respond to three different objectives. First, the need to associate information from the Facility Report to the individual BIM components to predict and monitor the conditions in which museum collections are found. Second, the intention to measure the attractiveness of the artifacts within the exhibition project and the design effects for a correct prefiguration of visitor flows. Third, the elements involved included the exhibition area obtained from an HBIM model (converted into a visual field through interoperable processes), the digitized collections (the attractive elements), the users and, finally, the numerical evaluation of the visibility of specific objects within collections by simulating the human point of view. Once automated, the devised procedures can be considered a prototype to support curators in controlling and improving the efficiency of the exhibition layout
Automatic workflow for narrow-band laryngeal video stitching
In narrow band (NB) laryngeal endoscopy, the clinician usually positions the endoscope near the tissue for a correct inspection of possible vascular pattern alterations, indicative of laryngeal malignancies. The video is usually reviewed many times to refine the diagnosis, resulting in loss of time since the salient frames of the video are mixed with blurred, noisy, and redundant frames caused by the endoscope movements. The aim of this work is to provide to the clinician a unique larynx panorama, obtained through an automatic frame selection strategy to discard non-informative frames. Anisotropic diffusion filtering was exploited to lower the noise level while encouraging the selection of meaningful image features, and a feature-based stitching approach was carried out to generate the panorama. The frame selection strategy, tested on on six pathological NB endoscopic videos, was compared with standard strategies, as uniform and random sampling, showing higher performance of the subsequent stitching procedure, both visually, in terms of vascular structure preservation, and numerically, through a blur estimation metric
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Patterns of injury and violence in Yaoundé Cameroon: an analysis of hospital data.
BackgroundInjuries are quickly becoming a leading cause of death globally, disproportionately affecting sub-Saharan Africa, where reports on the epidemiology of injuries are extremely limited. Reports on the patterns and frequency of injuries are available from Cameroon are also scarce. This study explores the patterns of trauma seen at the emergency ward of the busiest trauma center in Cameroon's capital city.Materials and methodsAdministrative records from January 1, 2007, through December 31, 2007, were retrospectively reviewed; information on age, gender, mechanism of injury, and outcome was abstracted for all trauma patients presenting to the emergency ward. Univariate analysis was performed to assess patterns of injuries in terms of mechanism, date, age, and gender. Bivariate analysis was used to explore potential relationships between demographic variables and mechanism of injury.ResultsA total of 6,234 injured people were seen at the Central Hospital of Yaoundé's emergency ward during the year 2007. Males comprised 71% of those injured, and the mean age of injured patients was 29 years (SD = 14.9). Nearly 60% of the injuries were due to road traffic accidents, 46% of which involved a pedestrian. Intentional injuries were the second most common mechanism of injury (22.5%), 55% of which involved unarmed assault. Patients injured in falls were more likely to be admitted to the hospital (p < 0.001), whereas patients suffering intentional injuries and bites were less likely to be hospitalized (p < 0.001). Males were significantly more likely to be admitted than females (p < 0.001)DiscussionPatterns in terms of age, gender, and mechanism of injury are similar to reports from other countries from the same geographic region, but the magnitude of cases reported is high for a single institution in an African city the size of Yaoundé. As the burden of disease is predicted to increase dramatically in sub-Saharan Africa, immediate efforts in prevention and treatment in Cameroon are strongly warranted
An exhibition on biomedical engineering for Vattenhallen Science Center LTH
This thesis contains the basis for an exhibition about biomedical engineering due to be displayed at Vattenhallen in the summer of 2013. The aim of the exhibition is to inspire and interest the children and adults that come and visits Vattenhallen. Hopefully at least one child will feel interested at study at LTH in the future. The basis contains 13 experimental stations and a short description of a potential laboration. Apart from these 13 stations three experiments have been constructed as well. An EMG-controlled prosthetic hand, an ultrasound phantom in the form of a 13 week old fetus and a software program for an experiment about MR/CT imaging. The experimental stations are: At the hospital Tissues MR Ultrasound The way through the stomach and bowel system Key hole surgery Your fantastic body The EMG controlled hand ECG Tinnitus Dialysis Microfluids The laboration: Servoventilato
Etruscans in 3D - Surveying and 3D modeling for a better access and understanding of heritage -
[EN] Archaeological 3D digital documentation of monuments and historical sites should be considered a precious source of information and it can be very useful for preservation, conservation, restoration and reconstruction of Cultural Heritage. This paper reports a work dealing with 3D surveying and modeling of different Etruscan heritage sites, featuring necropolis with underground frescoed tombs dating back to VII-IV century B.C., located in the area corresponding roughly to the actual central Italy. The project “Etruscans in 3D” was born with the aim of digital documentation, study, analyses and preservation of Etruscan heritage monuments and sites, but also to create digital contents for virtual visits, museum exhibitions, virtual and augmented reality, better access and communication of theheritage information.[ES] La documentación digital arqueológica en 3D de monumentos y yacimientos históricos es una valiosa fuente de información, muy útil tanto para la preservación y conservación, como para la restauración y reconstrucción del Patrimonio Cultural. En este artículo se expone el trabajo realizado en diferentes yacimientos del patrimonio etrusco, el levantamiento en 3D y el modelado de diferentes tumbas subterráneas decoradas con frescos (IV-VII a.C.), ubicadas en el centro de Italia. El proyecto "Etruscos 3D", nació con el objetivo de documentar (en formato digital), estudiar, analizar y conservar los diferentes monumentos y yacimientos del Patrimonio Etrusco, permitiendo un mejor acceso y comunicación de la información, así como crear contenidos digitales que sirvan para el desarrollo de exposiciones y visitas virtuales.Jiménez Fernández-Palacios, B.; Rizzi, A.; Remondino, F. (2015). Etruscans in 3D - Surveying and 3D modeling for a better access and understanding of heritage -. Virtual Archaeology Review. 4(8):85-89. https://doi.org/10.4995/var.2013.4324OJS858948PELAGOTTI, A., DEL MASTIO A., DE ROSA, A., PIVA, A. (2008): "Multispectral imaging of paintings - a way to material identification". IEEE Signal Processing Magazine, 25(4), pp. 27-36. http://dx.doi.org/10.1109/MSP.2008.923095REMONDINO, F., RIZZI, A., JIMENEZ, B., AGUGIARO, G., BARATTI, G., DE AMICIS, R. (2011a): "The Etruscan in 3D: from space to underground". 23th Int. CIPA Symposium, Prague, Czech Republic (on CD-Rom). http://dx.doi.org/10.14311/gi.6.35REMONDINO, F., RIZZI, A., BARAZZETTI, L., SCAIONI, M., FASSI, F., BRUMANA, R., PELAGOTTI, A. (2011b): "Review of geometric and radiometric analyses of paintings". The Photogrammetric Record, Vol. 26(136), pp. 439-461. http://dx.doi.org/10.1111/j.1477-9730.2011.00664.xRIZZI, A., BARATTI, G., JIMENEZ, B., GIRARDI, S., REMONDINO, F. (2011): "3D recording for 2D delivering - The employment of 3D models for studies and analyses". Int. Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. 38(5/W16), (on CD-Rom)
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