WorldWideScience

Sample records for diagnostic quality video

  1. Delivering Diagnostic Quality Video over Mobile Wireless Networks for Telemedicine

    Directory of Open Access Journals (Sweden)

    Sira P. Rao

    2009-01-01

    Full Text Available In real-time remote diagnosis of emergency medical events, mobility can be enabled by wireless video communications. However, clinical use of this potential advance will depend on definitive and compelling demonstrations of the reliability of diagnostic quality video. Because the medical domain has its own fidelity criteria, it is important to incorporate diagnostic video quality criteria into any video compression system design. To this end, we used flexible algorithms for region-of-interest (ROI video compression and obtained feedback from medical experts to develop criteria for diagnostically lossless (DL quality. The design of the system occurred in three steps-measurement of bit rate at which DL quality is achieved through evaluation of videos by medical experts, incorporation of that information into a flexible video encoder through the notion of encoder states, and an encoder state update option based on a built-in quality criterion. Medical experts then evaluated our system for the diagnostic quality of the video, allowing us to verify that it is possible to realize DL quality in the ROI at practical communication data transfer rates, enabling mobile medical assessment over bit-rate limited wireless channels. This work lays the scientific foundation for additional validation through prototyped technology, field testing, and clinical trials.

  2. Quality assessment for wireless capsule endoscopy videos compressed via HEVC: From diagnostic quality to visual perception.

    Science.gov (United States)

    Usman, Muhammad Arslan; Usman, Muhammad Rehan; Shin, Soo Young

    2017-12-01

    Maintaining the quality of medical images and videos is an essential part of the e-services provided by the healthcare sector. The convergence of modern communication systems and the healthcare industry necessitates the provision of better quality of service and experience by the service provider. Recent inclusion and standardization of the high efficiency video coder (HEVC) has made it possible for medical data to be compressed and transmitted over wireless networks with minimal compromise of the quality. Quality evaluation and assessment of these medical videos transmitted over wireless networks is another important research area that requires further exploration and attention. In this paper, we have conducted an in-depth study of video quality assessment for compressed wireless capsule endoscopy (WCE) videos. Our study includes the performance evaluation of several state-of-the-art objective video quality metrics in terms of determining the quality of compressed WCE videos. Subjective video quality experiments were conducted with the assistance of experts and non-experts in order to predict the diagnostic and visual quality of these medical videos, respectively. The evaluation of the metrics is based on three major performance metrics that include, correlation between the subjective and objective scores, relative statistical performance and computation time. Results show that the metrics information fidelity criterion (IFC), visual information fidelity-(VIF) and especially pixel based VIF stand out as best performing metrics. Furthermore, our paper reports the performance of HEVC compression on medical videos and according to the results, it performs optimally in preserving the diagnostic and visual quality of WCE videos at Quantization Parameter (QP) values of up to 35 and 37 respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Innovative Video Diagnostic Equipment for Material Science

    Science.gov (United States)

    Capuano, G.; Titomanlio, D.; Soellner, W.; Seidel, A.

    2012-01-01

    Materials science experiments under microgravity increasingly rely on advanced optical systems to determine the physical properties of the samples under investigation. This includes video systems with high spatial and temporal resolution. The acquisition, handling, storage and transmission to ground of the resulting video data are very challenging. Since the available downlink data rate is limited, the capability to compress the video data significantly without compromising the data quality is essential. We report on the development of a Digital Video System (DVS) for EML (Electro Magnetic Levitator) which provides real-time video acquisition, high compression using advanced Wavelet algorithms, storage and transmission of a continuous flow of video with different characteristics in terms of image dimensions and frame rates. The DVS is able to operate with the latest generation of high-performance cameras acquiring high resolution video images up to 4Mpixels@60 fps or high frame rate video images up to about 1000 fps@512x512pixels.

  4. Video Quality Prediction over Wireless 4G

    KAUST Repository

    Lau, Chun Pong

    2013-04-14

    In this paper, we study the problem of video quality prediction over the wireless 4G network. Video transmission data is collected from a real 4G SCM testbed for investigating factors that affect video quality. After feature transformation and selection on video and network parameters, video quality is predicted by solving as regression problem. Experimental results show that the dominated factor on video quality is the channel attenuation and video quality can be well estimated by our models with small errors.

  5. Video integrated measurement system. [Diagnostic display devices

    Energy Technology Data Exchange (ETDEWEB)

    Spector, B.; Eilbert, L.; Finando, S.; Fukuda, F.

    1982-06-01

    A Video Integrated Measurement (VIM) System is described which incorporates the use of various noninvasive diagnostic procedures (moire contourography, electromyography, posturometry, infrared thermography, etc.), used individually or in combination, for the evaluation of neuromusculoskeletal and other disorders and their management with biofeedback and other therapeutic procedures. The system provides for measuring individual diagnostic and therapeutic modes, or multiple modes by split screen superimposition, of real time (actual) images of the patient and idealized (ideal-normal) models on a video monitor, along with analog and digital data, graphics, color, and other transduced symbolic information. It is concluded that this system provides an innovative and efficient method by which the therapist and patient can interact in biofeedback training/learning processes and holds considerable promise for more effective measurement and treatment of a wide variety of physical and behavioral disorders.

  6. Video quality assessment for web content mirroring

    Science.gov (United States)

    He, Ye; Fei, Kevin; Fernandez, Gustavo A.; Delp, Edward J.

    2014-03-01

    Due to the increasing user expectation on watching experience, moving web high quality video streaming content from the small screen in mobile devices to the larger TV screen has become popular. It is crucial to develop video quality metrics to measure the quality change for various devices or network conditions. In this paper, we propose an automated scoring system to quantify user satisfaction. We compare the quality of local videos with the videos transmitted to a TV. Four video quality metrics, namely Image Quality, Rendering Quality, Freeze Time Ratio and Rate of Freeze Events are used to measure video quality change during web content mirroring. To measure image quality and rendering quality, we compare the matched frames between the source video and the destination video using barcode tools. Freeze time ratio and rate of freeze events are measured after extracting video timestamps. Several user studies are conducted to evaluate the impact of each objective video quality metric on the subjective user watching experience.

  7. No Reference Video-Quality-Assessment Model for Monitoring Video Quality of IPTV Services

    Science.gov (United States)

    Yamagishi, Kazuhisa; Okamoto, Jun; Hayashi, Takanori; Takahashi, Akira

    Service providers should monitor the quality of experience of a communication service in real time to confirm its status. To do this, we previously proposed a packet-layer model that can be used for monitoring the average video quality of typical Internet protocol television content using parameters derived from transmitted packet headers. However, it is difficult to monitor the video quality per user using the average video quality because video quality depends on the video content. To accurately monitor the video quality per user, a model that can be used for estimating the video quality per video content rather than the average video quality should be developed. Therefore, to take into account the impact of video content on video quality, we propose a model that calculates the difference in video quality between the video quality of the estimation-target video and the average video quality estimated using a packet-layer model. We first conducted extensive subjective quality assessments for different codecs and video sequences. We then model their characteristics based on parameters related to compression and packet loss. Finally, we verify the performance of the proposed model by applying it to unknown data sets different from the training data sets used for developing the model.

  8. Quality of Experience Assessment of Video Quality in Social Clouds

    Directory of Open Access Journals (Sweden)

    Asif Ali Laghari

    2017-01-01

    Full Text Available Video sharing on social clouds is popular among the users around the world. High-Definition (HD videos have big file size so the storing in cloud storage and streaming of videos with high quality from cloud to the client are a big problem for service providers. Social clouds compress the videos to save storage and stream over slow networks to provide quality of service (QoS. Compression of video decreases the quality compared to original video and parameters are changed during the online play as well as after download. Degradation of video quality due to compression decreases the quality of experience (QoE level of end users. To assess the QoE of video compression, we conducted subjective (QoE experiments by uploading, sharing, and playing videos from social clouds. Three popular social clouds, Facebook, Tumblr, and Twitter, were selected to upload and play videos online for users. The QoE was recorded by using questionnaire given to users to provide their experience about the video quality they perceive. Results show that Facebook and Twitter compressed HD videos more as compared to other clouds. However, Facebook gives a better quality of compressed videos compared to Twitter. Therefore, users assigned low ratings for Twitter for online video quality compared to Tumblr that provided high-quality online play of videos with less compression.

  9. Subjective video quality comparison of HDTV monitors

    Science.gov (United States)

    Seo, G.; Lim, C.; Lee, S.; Lee, C.

    2009-01-01

    HDTV broadcasting services have become widely available. Furthermore, in the upcoming IPTV services, HDTV services are important and quality monitoring becomes an issue, particularly in IPTV services. Consequently, there have been great efforts to develop video quality measurement methods for HDTV. On the other hand, most HDTV programs will be watched on digital TV monitors which include LCD and PDP TV monitors. In general, the LCD and PDP TV monitors have different color characteristics and response times. Furthermore, most commercial TV monitors include post-processing to improve video quality. In this paper, we compare subjective video quality of some commercial HD TV monitors to investigate the impact of monitor type on perceptual video quality. We used the ACR method as a subjective testing method. Experimental results show that the correlation coefficients among the HDTV monitors are reasonable high. However, for some video sequences and impairments, some differences in subjective scores were observed.

  10. Automated Video Quality Assessment for Deep-Sea Video

    Science.gov (United States)

    Pirenne, B.; Hoeberechts, M.; Kalmbach, A.; Sadhu, T.; Branzan Albu, A.; Glotin, H.; Jeffries, M. A.; Bui, A. O. V.

    2015-12-01

    Video provides a rich source of data for geophysical analysis, often supplying detailed information about the environment when other instruments may not. This is especially true of deep-sea environments, where direct visual observations cannot be made. As computer vision techniques improve and volumes of video data increase, automated video analysis is emerging as a practical alternative to labor-intensive manual analysis. Automated techniques can be much more sensitive to video quality than their manual counterparts, so performing quality assessment before doing full analysis is critical to producing valid results.Ocean Networks Canada (ONC), an initiative of the University of Victoria, operates cabled ocean observatories that supply continuous power and Internet connectivity to a broad suite of subsea instruments from the coast to the deep sea, including video and still cameras. This network of ocean observatories has produced almost 20,000 hours of video (about 38 hours are recorded each day) and an additional 8,000 hours of logs from remotely operated vehicle (ROV) dives. We begin by surveying some ways in which deep-sea video poses challenges for automated analysis, including: 1. Non-uniform lighting: Single, directional, light sources produce uneven luminance distributions and shadows; remotely operated lighting equipment are also susceptible to technical failures. 2. Particulate noise: Turbidity and marine snow are often present in underwater video; particles in the water column can have sharper focus and higher contrast than the objects of interest due to their proximity to the light source and can also influence the camera's autofocus and auto white-balance routines. 3. Color distortion (low contrast): The rate of absorption of light in water varies by wavelength, and is higher overall than in air, altering apparent colors and lowering the contrast of objects at a distance.We also describe measures under development at ONC for detecting and mitigating

  11. Perceived Quality of Full HD Video - Subjective Quality Assessment

    Directory of Open Access Journals (Sweden)

    Juraj Bienik

    2016-01-01

    Full Text Available In recent years, an interest in multimedia services has become a global trend and this trend is still rising. The video quality is a very significant part from the bundle of multimedia services, which leads to a requirement for quality assessment in the video domain. Video quality of a streamed video across IP networks is generally influenced by two factors “transmission link imperfection and efficiency of compression standards. This paper deals with subjective video quality assessment and the impact of the compression standards H.264, H.265 and VP9 on perceived video quality of these compression standards. The evaluation is done for four full HD sequences, the difference of scenes is in the content“ distinction is based on Spatial (SI and Temporal (TI Index of test sequences. Finally, experimental results follow up to 30% bitrate reducing of H.265 and VP9 compared with the reference H.264.

  12. Video Quality Prediction Models Based on Video Content Dynamics for H.264 Video over UMTS Networks

    Directory of Open Access Journals (Sweden)

    Asiya Khan

    2010-01-01

    Full Text Available The aim of this paper is to present video quality prediction models for objective non-intrusive, prediction of H.264 encoded video for all content types combining parameters both in the physical and application layer over Universal Mobile Telecommunication Systems (UMTS networks. In order to characterize the Quality of Service (QoS level, a learning model based on Adaptive Neural Fuzzy Inference System (ANFIS and a second model based on non-linear regression analysis is proposed to predict the video quality in terms of the Mean Opinion Score (MOS. The objective of the paper is two-fold. First, to find the impact of QoS parameters on end-to-end video quality for H.264 encoded video. Second, to develop learning models based on ANFIS and non-linear regression analysis to predict video quality over UMTS networks by considering the impact of radio link loss models. The loss models considered are 2-state Markov models. Both the models are trained with a combination of physical and application layer parameters and validated with unseen dataset. Preliminary results show that good prediction accuracy was obtained from both the models. The work should help in the development of a reference-free video prediction model and QoS control methods for video over UMTS networks.

  13. Impact of Compression on the Video Quality

    Directory of Open Access Journals (Sweden)

    Miroslav Uhrina

    2012-01-01

    Full Text Available This article deals with the impact of compression on the video quality. In the first part, a short characteristic of the most used MPEG compression standards is written. In the second part, the parameter Group of Picture (GOP with particular I, P, B frames is explained. The third part focuses on the objective metrics which were used for evaluating the video quality. In the fourth part, the measurements and the experimental results are described.

  14. Attention modeling for video quality assessment

    DEFF Research Database (Denmark)

    You, Junyong; Korhonen, Jari; Perkis, Andrew

    2010-01-01

    averaged spatiotemporal pooling. The local quality is derived from visual attention modeling and quality variations over frames. Saliency, motion, and contrast information are taken into account in modeling visual attention, which is then integrated into IQMs to calculate the local quality of a video frame...

  15. 13 point video tape quality guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Gaunt, R.

    1997-05-01

    Until high definition television (ATV) arrives, in the U.S. we must still contend with the National Television Systems Committee (NTSC) video standard (or PAL or SECAM-depending on your country). NTSC, a 40-year old standard designed for transmission of color video camera images over a small bandwidth, is not well suited for the sharp, full-color images that todays computers are capable of producing. PAL and SECAM also suffers from many of NTSC`s problems, but to varying degrees. Video professionals, when working with computer graphic (CG) images, use two monitors: a computer monitor for producing CGs and an NTSC monitor to view how a CG will look on video. More often than not, the NTSC image will differ significantly from the CG image, and outputting it to NTSC as an artist works enables the him or her to see the images as others will see it. Below are thirteen guidelines designed to increase the quality of computer graphics recorded onto video tape. Viewing your work in NTSC and attempting to follow the below tips will enable you to create higher quality videos. No video is perfect, so don`t expect to abide by every guideline every time.

  16. Quality and diagnostic perspectives in laboratory diagnostics

    OpenAIRE

    Müller, Mathias M.

    2010-01-01

    Laboratory diagnostics is a medical discipline playing an important part in patient management. In laboratory medicine meaningful, accurate and precise routine measurements are essential for diagnosis, risk assessment, treatment and follow-up of patients. The contribution of the diagnostic laboratory in the overall diagnostic process is app. 40-60%, depending on the kind of disease status investigated. The diagnostic laboratory uses nowadays more than 1.000 different tests mostly provided by ...

  17. Multispectral Video-Microscope Modified for Skin Diagnostics

    Directory of Open Access Journals (Sweden)

    Rubins U.

    2014-12-01

    Full Text Available Commercial DinoLite AD413 digital microscope was modified for skin diagnostics purposes. The original LED ring (4 white and 4 ultraviolet light emitters of microscope was replaced by a custom-designed 16-LED ring module consisting of four LED groups (450, 545, 660 and 940 nm, and an onboard LED controller with USB hub was added. The video acquisition and LED switching are performed using custom-designed Matlab software which provides real-time spectral analysis of multi-spectral images and calculation of skin chromophore optical density. The developed multispectral video-microscope is mainly meant for diagnostics of skin malformations, e.g. skin cancerous lesions.

  18. Overview video diagnostics for the W7-X stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Kocsis, G., E-mail: kocsis.gabor@wigner.mta.hu [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); Baross, T. [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); Biedermann, C. [Max-Planck-Institute for Plasma Physics, 17491 Greifswald (Germany); Bodnár, G.; Cseh, G.; Ilkei, T. [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary); König, R.; Otte, M. [Max-Planck-Institute for Plasma Physics, 17491 Greifswald (Germany); Szabolics, T.; Szepesi, T.; Zoletnik, S. [Wigner RCP, RMI, Konkoly Thege 29-33, H-1121 Budapest (Hungary)

    2015-10-15

    Considering the requirements of the newly built Wendelstein 7-X stellarator a ten-channel overview video diagnostic system was developed and is presently under installation. The system covering the whole torus interior can be used not only to observe the plasma but also to detect irregular operational events which are dangerous for the stellarator itself and to send automatic warning for the machine safety. The ten tangential AEQ ports used by the diagnostic remain under atmospheric pressure, the vacuum/air interface is at the front window located at the plasma side of the AEQ port. The optical vacuum window is protected by a cooled pinhole. The Sensor Module (SM) of the intelligent camera (EDICAM) – developed especially for this purpose – is located directly behind the vacuum window. EDICAM is designed to simultaneously record several regions of interest of its CMOS sensor with different frame rate and to detect various predefined events in real time. The air cooled SM is fixed by a docking mechanism which can preserve the pointing of the view. EDICAM can withstand the magnetic field (∼3 T), the neutron and gamma fluxes expected in the AEQ port. In order to adopt the new features of the video diagnostics system both control and data acquisition and visualization and data processing softwares are developed.

  19. The Significance of Video-Mediastinoscopy in Diagnostic Accuracy

    Directory of Open Access Journals (Sweden)

    Murat Oncel

    2013-08-01

    Full Text Available Purpose: Video-mediastinoscopy, which has been recently employed, is a method for the diagnosis of mediastinal diseases and staging lung cancer. Material and Method: In our study, we retrospectively evaluated patients admitted to our clinic between 2008-2011 to determine the diagnostic success of video-mediastinoscopy. Results: A total of 58 (88% cases out of 66 were diagnosed. Lymphadenopathy was not observed in 2 cases. Sarcoidosis was the most common type of mediastinal pathology seen in 28 (67% cases. Tuberculous lymphadenitis was the second most common seen in 11 (27% cases. Eight (5.3% cases had anthrocosis, and 12 cases had reactive lymphadenitis. N3 counterpart staging was performed. Two of them were found to be positive. N2 found to be positive in 4 cases. These findings were correlated with PET scan. Mortality was not observed in any of the patients. Repeated mediastinoscopy for investigating N3 in one patient leads to disappearance of temporary hoarseness after about 2 months, which occurred due to paralysis recurrens. One patient had cervical subcutaneous emphysema, and one had major bleeding. Conclusion: Video-mediastinoscopy is a highly effective tool and important in finalizing the diagnosis. Moreover, it is reliable for the complete secure exploration of the mass, which we believe that it could be used in all patients required especially those with thoracic and mediastinal pathologies. [Cukurova Med J 2013; 38(4.000: 719-722

  20. Quality metric for spherical panoramic video

    Science.gov (United States)

    Zakharchenko, Vladyslav; Choi, Kwang Pyo; Park, Jeong Hoon

    2016-09-01

    Virtual reality (VR)/ augmented reality (AR) applications allow users to view artificial content of a surrounding space simulating presence effect with a help of special applications or devices. Synthetic contents production is well known process form computer graphics domain and pipeline has been already fixed in the industry. However emerging multimedia formats for immersive entertainment applications such as free-viewpoint television (FTV) or spherical panoramic video require different approaches in content management and quality assessment. The international standardization on FTV has been promoted by MPEG. This paper is dedicated to discussion of immersive media distribution format and quality estimation process. Accuracy and reliability of the proposed objective quality estimation method had been verified with spherical panoramic images demonstrating good correlation results with subjective quality estimation held by a group of experts.

  1. Display device-adapted video quality-of-experience assessment

    Science.gov (United States)

    Rehman, Abdul; Zeng, Kai; Wang, Zhou

    2015-03-01

    Today's viewers consume video content from a variety of connected devices, including smart phones, tablets, notebooks, TVs, and PCs. This imposes significant challenges for managing video traffic efficiently to ensure an acceptable quality-of-experience (QoE) for the end users as the perceptual quality of video content strongly depends on the properties of the display device and the viewing conditions. State-of-the-art full-reference objective video quality assessment algorithms do not take into account the combined impact of display device properties, viewing conditions, and video resolution while performing video quality assessment. We performed a subjective study in order to understand the impact of aforementioned factors on perceptual video QoE. We also propose a full reference video QoE measure, named SSIMplus, that provides real-time prediction of the perceptual quality of a video based on human visual system behaviors, video content characteristics (such as spatial and temporal complexity, and video resolution), display device properties (such as screen size, resolution, and brightness), and viewing conditions (such as viewing distance and angle). Experimental results have shown that the proposed algorithm outperforms state-of-the-art video quality measures in terms of accuracy and speed.

  2. EDICAM fast video diagnostic installation on the COMPASS tokamak

    Czech Academy of Sciences Publication Activity Database

    Szappanos, A.; Berta, M.; Hron, Martin; Pánek, Radomír; Stöckel, Jan; Veres, G.; Weinzettl, Vladimír; Zoletnik, S.; Tulipán, S.

    2010-01-01

    Roč. 85, 3-4 (2010), s. 370-373 ISSN 0920-3796. [IAEA Technical Meeting on Control, Data Acquisition and Remote Participation for Fusion Research/7th./. Aix – en – Provence, 15.06.2009-19.06.2009] Institutional research plan: CEZ:AV0Z20430508 Keywords : Video diagnostic * Fast data processing * CMOS sensor * Image processing Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.143, year: 2010 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V3C-4Y0C2FK-1&_user=6542793&_coverDate=07%2F31%2F2010&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_acct=C000070123&_version=1&_urlVersion=0&_userid=6542793&md5=99eb6704be38e61ac7e2316cb63a7ee9&searchtype=a

  3. Video processing for human perceptual visual quality-oriented video coding.

    Science.gov (United States)

    Oh, Hyungsuk; Kim, Wonha

    2013-04-01

    We have developed a video processing method that achieves human perceptual visual quality-oriented video coding. The patterns of moving objects are modeled by considering the limited human capacity for spatial-temporal resolution and the visual sensory memory together, and an online moving pattern classifier is devised by using the Hedge algorithm. The moving pattern classifier is embedded in the existing visual saliency with the purpose of providing a human perceptual video quality saliency model. In order to apply the developed saliency model to video coding, the conventional foveation filtering method is extended. The proposed foveation filter can smooth and enhance the video signals locally, in conformance with the developed saliency model, without causing any artifacts. The performance evaluation results confirm that the proposed video processing method shows reliable improvements in the perceptual quality for various sequences and at various bandwidths, compared to existing saliency-based video coding methods.

  4. No-reference pixel based video quality assessment for HEVC decoded video

    DEFF Research Database (Denmark)

    Huang, Xin; Søgaard, Jacob; Forchhammer, Søren

    2017-01-01

    This paper proposes a No-Reference (NR) Video Quality Assessment (VQA) method for videos subject to the distortion given by the High Efficiency Video Coding (HEVC) scheme. The assessment is performed without access to the bitstream. The proposed analysis is based on the transform coefficients...... estimated from the decoded video pixels, which is used to estimate the level of quantization. The information from this analysis is exploited to assess the video quality. HEVC transform coefficients are modeled with a joint-Cauchy probability density function in the proposed method. To generate VQA features...... the quantization step used in the Intra coding is estimated. We map the obtained HEVC features using an Elastic Net to predict subjective video quality scores, Mean Opinion Scores (MOS). The performance is verified on a dataset consisting of HEVC coded 4 K UHD (resolution equal to 3840 x 2160) video sequences...

  5. Video quality measure for mobile IPTV service

    Science.gov (United States)

    Kim, Wonjun; Kim, Changick

    2008-08-01

    Mobile IPTV is a multimedia service based on wireless networks with interactivity and mobility. Under mobile IPTV scenarios, people can watch various contents whenever they want and even deliver their request to service providers through the network. However, the frequent change of the wireless channel bandwidth may hinder the quality of service. In this paper, we propose an objective video quality measure (VQM) for mobile IPTV services, which is focused on the jitter measurement. Jitter is the result of frame repetition during the delay and one of the most severe impairments in the video transmission via mobile channels. We first employ YUV color space to compute the duration and occurrences of jitter and the motion activity. Then the VQM is modeled by the combination of these three factors and the result of subjective assessment. Since the proposed VQM is based on no-reference (NR) model, it can be applied for real-time applications. Experimental results show that the proposed VQM highly correlates to subjective evaluation.

  6. No-Reference Video Quality Assessment by HEVC Codec Analysis

    DEFF Research Database (Denmark)

    Huang, Xin; Søgaard, Jacob; Forchhammer, Søren

    2015-01-01

    This paper proposes a No-Reference (NR) Video Quality Assessment (VQA) method for videos subject to the distortion given by High Efficiency Video Coding (HEVC). The proposed assessment can be performed either as a BitstreamBased (BB) method or as a Pixel-Based (PB). It extracts or estimates the t...

  7. Rate control scheme for consistent video quality in scalable video codec.

    Science.gov (United States)

    Seo, Chan-Won; Han, Jong-Ki; Nguyen, Truong Q

    2011-08-01

    Multimedia data delivered to mobile devices over wireless channels or the Internet are complicated by bandwidth fluctuation and the variety of mobile devices. Scalable video coding has been developed as an extension of H.264/AVC to solve this problem. Since scalable video codec provides various scalabilities to adapt the bitstream for the channel conditions and terminal types, scalable codec is one of the useful codecs for wired or wireless multimedia communication systems, such as IPTV and streaming services. In such scalable multimedia communication systems, video quality fluctuation degrades the visual perception significantly. It is important to efficiently use the target bits in order to maintain a consistent video quality or achieve a small distortion variation throughout the whole video sequence. The scheme proposed in this paper provides a useful function to control video quality in applications supporting scalability, whereas conventional schemes have been proposed to control video quality in the H.264 and MPEG-4 systems. The proposed algorithm decides the quantization parameter of the enhancement layer to maintain a consistent video quality throughout the entire sequence. The video quality of the enhancement layer is controlled based on a closed-form formula which utilizes the residual data and quantization error of the base layer. The simulation results show that the proposed algorithm controls the frame quality of the enhancement layer in a simple operation, where the parameter decision algorithm is applied to each frame.

  8. Quality Assessment of Compressed Video for Automatic License Plate Recognition

    DEFF Research Database (Denmark)

    Ukhanova, Ann; Støttrup-Andersen, Jesper; Forchhammer, Søren

    2014-01-01

    Definition of video quality requirements for video surveillance poses new questions in the area of quality assessment. This paper presents a quality assessment experiment for an automatic license plate recognition scenario. We explore the influence of the compression by H.264/AVC and H.265/HEVC...

  9. How to evaluate objective video quality metrics reliably

    DEFF Research Database (Denmark)

    Korhonen, Jari; Burini, Nino; You, Junyong

    2012-01-01

    The typical procedure for evaluating the performance of different objective quality metrics and indices involves comparisons between subjective quality ratings and the quality indices obtained using the objective metrics in question on the known video sequences. Several correlation indicators can...... as processing of subjective data. We also suggest some general guidelines for researchers to make comparison studies of objective video quality metrics more reliable and useful for the practitioners in the field.......The typical procedure for evaluating the performance of different objective quality metrics and indices involves comparisons between subjective quality ratings and the quality indices obtained using the objective metrics in question on the known video sequences. Several correlation indicators can...

  10. Effective Quality-of-Service Renegotiating Schemes for Streaming Video

    Directory of Open Access Journals (Sweden)

    Song Hwangjun

    2004-01-01

    Full Text Available This paper presents effective quality-of-service renegotiating schemes for streaming video. The conventional network supporting quality of service generally allows a negotiation at a call setup. However, it is not efficient for the video application since the compressed video traffic is statistically nonstationary. Thus, we consider the network supporting quality-of-service renegotiations during the data transmission and study effective quality-of-service renegotiating schemes for streaming video. The token bucket model, whose parameters are token filling rate and token bucket size, is adopted for the video traffic model. The renegotiating time instants and the parameters are determined by analyzing the statistical information of compressed video traffic. In this paper, two renegotiating approaches, that is, fixed renegotiating interval case and variable renegotiating interval case, are examined. Finally, the experimental results are provided to show the performance of the proposed schemes.

  11. Crowdsourcing based subjective quality assessment of adaptive video streaming

    DEFF Research Database (Denmark)

    Shahid, M.; Søgaard, Jacob; Pokhrel, J.

    2014-01-01

    humans are considered to be the most valid method of the as- sessment of QoE. Besides lab-based subjective experiments, crowdsourcing based subjective assessment of video quality is gaining popularity as an alternative method. This paper presents insights into a study that investigates perceptual pref......- erences of various adaptive video streaming scenarios through crowdsourcing based subjective quality assessment....

  12. Quality assurance programme for isotope diagnostic laboratories

    International Nuclear Information System (INIS)

    Krasznai, Istvan

    1987-01-01

    Quality assurance systems are suggested to be introduced in laboratories, in accordance with the recommendations of IAEA and WHO, taking local circumstances into consideration. It is emphasized that a quantitative enhancement of work must not endanger its quality; diagnostic information must be undistorted, reproducible, and gathered with the minimum of radiation burden. National authorities are requested to strengthen their supervision. Recommendations for quality assurance methods are given for medical isotope diagnostic laboratories. (author)

  13. No-Reference Video Quality Assessment using Codec Analysis

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Forchhammer, Søren; Korhonen, Jari

    2015-01-01

    A no-reference video quality assessment (VQA) method is presented for videos distorted by H.264/AVC and MPEG-2. The assessment is performed without access to the bit-stream. Instead we analyze and estimate coefficients based on decoded pixels. The approach involves distinguishing between the two...... types of videos, estimating the level of quantization used in the I-frames, and exploiting this information to assess the video quality. In order to do this for H.264/AVC, the distribution of the DCT-coefficients after intra-prediction and deblocking are modeled. To obtain VQA features for H.264/AVC, we...... propose a novel estimation method of the quantization in H.264/AVC videos without bitstream access, which can also be used for Peak Signalto-Noise Ratio (PSNR) estimation. The results from the MPEG-2 and H.264/AVC analysis are mapped to a perceptual measure of video quality by Support Vector Regression...

  14. Offset Trace-Based Video Quality Evaluation Network Transport

    DEFF Research Database (Denmark)

    Seeling, P.; Reisslein, M.; Fitzek, Frank

    2006-01-01

    Video traces contain information about encoded video frames, such as frame sizes and qualities, and provide a convenient method to conduct multimedia networking research. Although wiedely used in networking research, these traces do not allow to determine the video qaulityin an accurate manner...... after networking transport that includes losses and delays. In this work, we provide (i) an overview of frame dependencies that have to be taken into consideration when working with video traces, (ii) an algorithmic approach to combine traditional video traces and offset distortion traces to determine...... the video quality or distortion after lossy network transport, (iii) offset distortion and quality characteristics and (iv) the offset distortion trace format and tools to create offset distortion traces....

  15. Toward a direct measure of video quality perception using EEG.

    Science.gov (United States)

    Scholler, Simon; Bosse, Sebastian; Treder, Matthias Sebastian; Blankertz, Benjamin; Curio, Gabriel; Müller, Klaus-Robert; Wiegand, Thomas

    2012-05-01

    An approach to the direct measurement of perception of video quality change using electroencephalography (EEG) is presented. Subjects viewed 8-s video clips while their brain activity was registered using EEG. The video signal was either uncompressed at full length or changed from uncompressed to a lower quality level at a random time point. The distortions were introduced by a hybrid video codec. Subjects had to indicate whether they had perceived a quality change. In response to a quality change, a positive voltage change in EEG (the so-called P3 component) was observed at latency of about 400-600 ms for all subjects. The voltage change positively correlated with the magnitude of the video quality change, substantiating the P3 component as a graded neural index of the perception of video quality change within the presented paradigm. By applying machine learning techniques, we could classify on a single-trial basis whether a subject perceived a quality change. Interestingly, some video clips wherein changes were missed (i.e., not reported) by the subject were classified as quality changes, suggesting that the brain detected a change, although the subject did not press a button. In conclusion, abrupt changes of video quality give rise to specific components in the EEG that can be detected on a single-trial basis. Potentially, a neurotechnological approach to video assessment could lead to a more objective quantification of quality change detection, overcoming the limitations of subjective approaches (such as subjective bias and the requirement of an overt response). Furthermore, it allows for real-time applications wherein the brain response to a video clip is monitored while it is being viewed.

  16. Quality assurance, quality control and quality audit in diagnostic radiology

    International Nuclear Information System (INIS)

    Vassileva, J.

    2009-01-01

    Full text:The lecture aims to present contemporary view of quality assurance in X-Ray diagnosis and its practical realization in Bulgaria. In the lecture the concepts of quality assurance, quality control and clinical audit will be defined and their scope will be considered. An answer of the following questions will be given: why is it necessary to determine the dose of patient in X-ray studies, what is the reference dose level and how it is used for dosimetric quantity which characterized the patient's exposure in X-ray, mammography and CT scans and how they are measured, who conducted the measurement and how to keep the records, what are the variations of doses in identical tests and what defines them? The findings from a national survey of doses in diagnostic radiology, conducted in 2008-2009 and the developed new national reference levels will be presented. The main findings of the first tests of radiological equipment and the future role of quality control as well as the concept of conducting clinical audit and its role in quality assurance are also presented. Quality assurance of the diagnostic process with minimal exposure of patients is a strategic goal whose realization requires understanding, organization and practical action, both nationally and in every hospital. To achieve this the important role of education and training of physicians, radiological technicians and medical physicists is enhanced

  17. Subjective Video Quality Assessment in H.264/AVC Video Coding Standard

    Directory of Open Access Journals (Sweden)

    Z. Miličević

    2012-11-01

    Full Text Available This paper seeks to provide an approach for subjective video quality assessment in the H.264/AVC standard. For this purpose a special software program for the subjective assessment of quality of all the tested video sequences is developed. It was developed in accordance with recommendation ITU-T P.910, since it is suitable for the testing of multimedia applications. The obtained results show that in the proposed selective intra prediction and optimized inter prediction algorithm there is a small difference in picture quality (signal-to-noise ratio between decoded original and modified video sequences.

  18. Frame Rate versus Spatial Quality: Which Video Characteristics Do Matter?

    DEFF Research Database (Denmark)

    Korhonen, Jari; Reiter, Ulrich; Ukhanova, Ann

    2013-01-01

    and temporal quality levels. We also propose simple yet powerful metrics for characterizing spatial and temporal properties of a video sequence, and demonstrate how these metrics can be applied for evaluating the relative impact of spatial and temporal quality on the perceived overall quality.......Several studies have shown that the relationship between perceived video quality and frame rate is dependent on the video content. In this paper, we have analyzed the content characteristics and compared them against the subjective results derived from preference decisions between different spatial...

  19. No-Reference Video Quality Assessment by HEVC Codec Analysis

    DEFF Research Database (Denmark)

    Huang, Xin; Søgaard, Jacob; Forchhammer, Søren

    2015-01-01

    This paper proposes a No-Reference (NR) Video Quality Assessment (VQA) method for videos subject to the distortion given by High Efficiency Video Coding (HEVC). The proposed assessment can be performed either as a BitstreamBased (BB) method or as a Pixel-Based (PB). It extracts or estimates...... the transform coefficients, estimates the distortion, and assesses the video quality. The proposed scheme generates VQA features based on Intra coded frames, and then maps features using an Elastic Net to predict subjective video quality. A set of HEVC coded 4K UHD sequences are tested. Results show...... that the quality scores computed by the proposed method are highly correlated with the subjective assessment....

  20. Developing Prospective Teachers' Diagnostic Skills through Collaborative Video Analysis: Focus on L2 Reading

    Science.gov (United States)

    Finkbeiner, Claudia; Schluer, Jennifer

    2017-01-01

    This paper contains a collaborative video-based approach to foster prospective teachers' diagnostic skills with respect to pupils' L2 reading processes. Together with a peer, the prospective teachers watched, systematically selected, analysed and commented on clips from a comprehensive video corpus on L2 reading strategies. In order to assist the…

  1. Study of Temporal Effects on Subjective Video Quality of Experience.

    Science.gov (United States)

    Bampis, Christos George; Zhi Li; Moorthy, Anush Krishna; Katsavounidis, Ioannis; Aaron, Anne; Bovik, Alan Conrad

    2017-11-01

    HTTP adaptive streaming is being increasingly deployed by network content providers, such as Netflix and YouTube. By dividing video content into data chunks encoded at different bitrates, a client is able to request the appropriate bitrate for the segment to be played next based on the estimated network conditions. However, this can introduce a number of impairments, including compression artifacts and rebuffering events, which can severely impact an end-user's quality of experience (QoE). We have recently created a new video quality database, which simulates a typical video streaming application, using long video sequences and interesting Netflix content. Going beyond previous efforts, the new database contains highly diverse and contemporary content, and it includes the subjective opinions of a sizable number of human subjects regarding the effects on QoE of both rebuffering and compression distortions. We observed that rebuffering is always obvious and unpleasant to subjects, while bitrate changes may be less obvious due to content-related dependencies. Transient bitrate drops were preferable over rebuffering only on low complexity video content, while consistently low bitrates were poorly tolerated. We evaluated different objective video quality assessment algorithms on our database and found that objective video quality models are unreliable for QoE prediction on videos suffering from both rebuffering events and bitrate changes. This implies the need for more general QoE models that take into account objective quality models, rebuffering-aware information, and memory. The publicly available video content as well as metadata for all of the videos in the new database can be found at http://live.ece.utexas.edu/research/LIVE_NFLXStudy/nflx_index.html.

  2. Quality Assessment of Compressed Video for Automatic License Plate Recognition

    DEFF Research Database (Denmark)

    Ukhanova, Ann; Støttrup-Andersen, Jesper; Forchhammer, Søren

    2014-01-01

    Definition of video quality requirements for video surveillance poses new questions in the area of quality assessment. This paper presents a quality assessment experiment for an automatic license plate recognition scenario. We explore the influence of the compression by H.264/AVC and H.265/HEVC...... standards on the recognition performance. We compare logarithmic and logistic functions for quality modeling. Our results show that a logistic function can better describe the dependence of recognition performance on the quality for both compression standards. We observe that automatic license plate...

  3. Objective video quality measure for application to tele-echocardiography.

    Science.gov (United States)

    Moore, Peter Thomas; O'Hare, Neil; Walsh, Kevin P; Ward, Neil; Conlon, Niamh

    2008-08-01

    Real-time tele-echocardiography is widely used to remotely diagnose or exclude congenital heart defects. Cost effective technical implementation is realised using low-bandwidth transmission systems and lossy compression (videoconferencing) schemes. In our study, DICOM video sequences were converted to common multimedia formats, which were then, compressed using three lossy compression algorithms. We then applied a digital (multimedia) video quality metric (VQM) to determine objectively a value for degradation due to compression. Three levels of compression were simulated by varying system bandwidth and compared to a subjective assessment of video clip quality by three paediatric cardiologists with more than 5 years of experience.

  4. Bandwidth allocation for video under quality of service constraints

    CERN Document Server

    Anjum, Bushra

    2014-01-01

    We present queueing-based algorithms to calculate the bandwidth required for a video stream so that the three main Quality of Service constraints, i.e., end-to-end delay, jitter and packet loss, are ensured. Conversational and streaming video-based applications are becoming a major part of the everyday Internet usage. The quality of these applications (QoS), as experienced by the user, depends on three main metrics of the underlying network, namely, end-to-end delay, jitter and packet loss. These metrics are, in turn, directly related to the capacity of the links that the video traffic trave

  5. Towards a Visual Quality Metric for Digital Video

    Science.gov (United States)

    Watson, Andrew B.

    1998-01-01

    The advent of widespread distribution of digital video creates a need for automated methods for evaluating visual quality of digital video. This is particularly so since most digital video is compressed using lossy methods, which involve the controlled introduction of potentially visible artifacts. Compounding the problem is the bursty nature of digital video, which requires adaptive bit allocation based on visual quality metrics. In previous work, we have developed visual quality metrics for evaluating, controlling, and optimizing the quality of compressed still images. These metrics incorporate simplified models of human visual sensitivity to spatial and chromatic visual signals. The challenge of video quality metrics is to extend these simplified models to temporal signals as well. In this presentation I will discuss a number of the issues that must be resolved in the design of effective video quality metrics. Among these are spatial, temporal, and chromatic sensitivity and their interactions, visual masking, and implementation complexity. I will also touch on the question of how to evaluate the performance of these metrics.

  6. Quality-Aware Estimation of Facial Landmarks in Video Sequences

    DEFF Research Database (Denmark)

    Haque, Mohammad Ahsanul; Nasrollahi, Kamal; Moeslund, Thomas B.

    2015-01-01

    Face alignment in video is a primitive step for facial image analysis. The accuracy of the alignment greatly depends on the quality of the face image in the video frames and low quality faces are proven to cause erroneous alignment. Thus, this paper proposes a system for quality aware face...... for facial landmark detection. If the face quality is low the proposed system corrects the facial landmarks that are detected by SDM. Depending upon the face velocity in consecutive video frames and face quality measure, two algorithms are proposed for correction of landmarks in low quality faces by using...... an extrapolation polynomial. Experimental results illustrate the competency of the proposed method while comparing with the state-of-theart methods including an SDM-based method (from CVPR-2013) and a very recent method (from CVPR-2014) that uses parallel cascade of linear regression (Par-CLR)....

  7. Home Video Telemetry vs inpatient telemetry: A comparative study looking at video quality

    Directory of Open Access Journals (Sweden)

    Sutapa Biswas

    Full Text Available Objective: To compare the quality of home video recording with inpatient telemetry (IPT to evaluate our current Home Video Telemetry (HVT practice. Method: To assess our HVT practice, a retrospective comparison of the video quality against IPT was conducted with the latter as the gold standard. A pilot study had been conducted in 2008 on 5 patients.Patients (n = 28 were included in each group over a period of one year.The data was collected from referral spreadsheets, King’s EPR and telemetry archive.Scoring of the events captured was by consensus using two scorers.The variables compared included: visibility of the body part of interest, visibility of eyes, time of event, illumination, contrast, sound quality and picture clarity when amplified to 200%.Statistical evaluation was carried out using Shapiro–Wilk and Chi-square tests. The P-value of ⩽0.05 was considered statistically significant. Results: Significant differences were demonstrated in lighting and contrast between the two groups (HVT performed better in both.Amplified picture quality was slightly better in the HVT group. Conclusion: Video quality of HVT is comparable to IPT, even surpassing IPT in certain aspects such as the level of illumination and contrast. Results were reconfirmed in a larger sample of patients with more variables. Significance: Despite the user and environmental variability in HVT, it looks promising and can be seriously considered as a preferable alternative for patients who may require investigation at locations remote from an EEG laboratory. Keywords: Home Video Telemetry, EEG, Home video monitoring, Video quality

  8. Video otoscopy as a diagnostic tool for canine otoacariasis

    Directory of Open Access Journals (Sweden)

    Clarissa Pimentel de Souza

    Full Text Available Canine otoacariasis, or otodectic mange, is a common parasitic disorder of dogs' ear canals caused by the mite Otodectes cynotis. Infestation can be detected through diverse protocols of varying sensitivity. We evaluated the use of video otoscopy in comparison with conventional otoscopy and cerumen examination under a microscope for diagnosingO. cynotis in dogs. Thirty-five dogs were evaluated bilaterally for the presence of ear mites, using a veterinary otoscope (Gowlands®, a video otoscope (Welch Allyn® and the gold-standard technique of examination of swab-collected cerumen under a microscope. Each ear was considered to represent one sample, and 69 ears were examined, since one dog presented with one completely stenotic ear canal. Ear mites were diagnosed in 59.42% (41/69 through video otoscopy. The same 41 infested ear canals were detected by means of cerumen examination under a microscope, whereas conventional otoscopy was able to diagnose mites in only 39.13% (27/69. This difference was statistically significant (p < 0.001. Video otoscopy proved to be superior to conventional otoscopy, and equivalent to the gold standard for detection of O. cynotis in canine ear canals, and should be recommended for controlled trials on drug efficacy for treatment of canine otoacariasis.

  9. Balancing Attended and Global Stimuli in Perceived Video Quality Assessment

    DEFF Research Database (Denmark)

    You, Junyong; Korhonen, Jari; Perkis, Andrew

    2011-01-01

    The visual attention mechanism plays a key role in the human perception system and it has a significant impact on our assessment of perceived video quality. In spite of receiving less attention from the viewers, unattended stimuli can still contribute to the understanding of the visual content....... This paper proposes a quality model based on the late attention selection theory, assuming that the video quality is perceived via two mechanisms: global and local quality assessment. First we model several visual features influencing the visual attention in quality assessment scenarios to derive...... an attention map using appropriate fusion techniques. The global quality assessment as based on the assumption that viewers allocate their attention equally to the entire visual scene, is modeled by four carefully designed quality features. By employing these same quality features, the local quality model...

  10. Estimating Video Quality over ADSL2+ under Impulsive Line Disturbance

    Science.gov (United States)

    Gonçalves, Glauco; Dantas, Ramide; Palhares, André; Kelner, Judith; Fidalgo, Joseane; Sadok, Djamel; Almeida, Henrik; Berg, Miguel; Cederholm, Daniel

    QoS Provisioning for 3P over xDSL remains a challenging task due to the effects of line impairments on such services. Differently from simple data, video and voice services have strict requirements for loss and delay tolerance. The accurate assessment of final service quality is part of this provisioning process, but its direct measurement is yet not practical. In this paper we explore the possibility of estimating service quality, with focus on video delivery, by investigating its relationship with performance data available to xDSL operators and deriving models for estimating quality from this data. Experiments using a real xDSL platform and different noise types were conducted. The derived models showed to be accurate enough to estimate video quality for the scenarios evaluated.

  11. Compensating for Type-I Errors in Video Quality Assessment

    DEFF Research Database (Denmark)

    Brunnström, Kjell; Tavakoli, Samira; Søgaard, Jacob

    2015-01-01

    This paper analyzes the impact on compensating for Type-I errors in video quality assessment. A Type-I error is to incorrectly conclude that there is an effect. The risk increases with the number of comparisons that are performed in statistical tests. Type-I errors are an issue often neglected in...... in Quality of Experience and video quality assessment analysis. Examples are given for the analysis of subjective experiments and the evaluation of objective metrics by correlation.......This paper analyzes the impact on compensating for Type-I errors in video quality assessment. A Type-I error is to incorrectly conclude that there is an effect. The risk increases with the number of comparisons that are performed in statistical tests. Type-I errors are an issue often neglected...

  12. Visual saliency models for summarization of diagnostic hysteroscopy videos in healthcare systems.

    Science.gov (United States)

    Muhammad, Khan; Ahmad, Jamil; Sajjad, Muhammad; Baik, Sung Wook

    2016-01-01

    In clinical practice, diagnostic hysteroscopy (DH) videos are recorded in full which are stored in long-term video libraries for later inspection of previous diagnosis, research and training, and as an evidence for patients' complaints. However, a limited number of frames are required for actual diagnosis, which can be extracted using video summarization (VS). Unfortunately, the general-purpose VS methods are not much effective for DH videos due to their significant level of similarity in terms of color and texture, unedited contents, and lack of shot boundaries. Therefore, in this paper, we investigate visual saliency models for effective abstraction of DH videos by extracting the diagnostically important frames. The objective of this study is to analyze the performance of various visual saliency models with consideration of domain knowledge and nominate the best saliency model for DH video summarization in healthcare systems. Our experimental results indicate that a hybrid saliency model, comprising of motion, contrast, texture, and curvature saliency, is the more suitable saliency model for summarization of DH videos in terms of extracted keyframes and accuracy.

  13. The art of assessing quality for images and video

    International Nuclear Information System (INIS)

    Deriche, M.

    2011-01-01

    The early years of this century have witnessed a tremendous growth in the use of digital multimedia data for di?erent communication applications. Researchers from around the world are spending substantial research efforts in developing techniques for improving the appearance of images/video. However, as we know, preserving high quality is a challenging task. Images are subject to distortions during acquisition, compression, transmission, analysis, and reconstruction. For this reason, the research area focusing on image and video quality assessment has attracted a lot of attention in recent years. In particular, compression applications and other multimedia applications need powerful techniques for evaluating quality objectively without human interference. This tutorial will cover the di?erent faces of image quality assessment. We will motivate the need for robust image quality assessment techniques, then discuss the main algorithms found in the literature with a critical perspective. We will present the di?erent metrics used for full reference, reduced reference and no reference applications. We will then discuss the difference between image and video quality assessment. In all of the above, we will take a critical approach to explain which metric can be used for which application. Finally we will discuss the different approaches to analyze the performance of image/video quality metrics, and end the tutorial with some perspectives on newly introduced metrics and their potential applications.

  14. Improving the Quality of Color Colonoscopy Videos

    Directory of Open Access Journals (Sweden)

    Dahyot Rozenn

    2008-01-01

    Full Text Available Abstract Colonoscopy is currently one of the best methods to detect colorectal cancer. Nowadays, one of the widely used colonoscopes has a monochrome chipset recording successively at 60 Hz and components merged into one color video stream. Misalignments of the channels occur each time the camera moves, and this artefact impedes both online visual inspection by doctors and offline computer analysis of the image data. We propose to restore this artefact by first equalizing the color channels and then performing a robust camera motion estimation and compensation.

  15. Towards Video Quality Metrics Based on Colour Fractal Geometry

    Directory of Open Access Journals (Sweden)

    Richard Noël

    2010-01-01

    Full Text Available Vision is a complex process that integrates multiple aspects of an image: spatial frequencies, topology and colour. Unfortunately, so far, all these elements were independently took into consideration for the development of image and video quality metrics, therefore we propose an approach that blends together all of them. Our approach allows for the analysis of the complexity of colour images in the RGB colour space, based on the probabilistic algorithm for calculating the fractal dimension and lacunarity. Given that all the existing fractal approaches are defined only for gray-scale images, we extend them to the colour domain. We show how these two colour fractal features capture the multiple aspects that characterize the degradation of the video signal, based on the hypothesis that the quality degradation perceived by the user is directly proportional to the modification of the fractal complexity. We claim that the two colour fractal measures can objectively assess the quality of the video signal and they can be used as metrics for the user-perceived video quality degradation and we validated them through experimental results obtained for an MPEG-4 video streaming application; finally, the results are compared against the ones given by unanimously-accepted metrics and subjective tests.

  16. Quality assurance testing on video games : The importance and impact of a misunderstood industry

    OpenAIRE

    Ruuska, Essi

    2015-01-01

    The aim of this research was to provide a more holistic insight of the video game quality assurance industry to video game industry professionals and prospective employees in order to promote the importance and impact of quality assurance testing in video games. The motive for this thesis came from the author's work experience in video game quality assurance testing, and from realizing how little is known about the industry. The research question was defined as 'what is video game quality ass...

  17. Computed Quality Assessment of MPEG4-compressed DICOM Video Data.

    Science.gov (United States)

    Frankewitsch, Thomas; Söhnlein, Sven; Müller, Marcel; Prokosch, Hans-Ulrich

    2005-01-01

    Digital Imaging and Communication in Medicine (DICOM) has become one of the most popular standards in medicine. This standard specifies the exact procedures in which digital images are exchanged between devices, either using a network or storage medium. Sources for images vary; therefore there exist definitions for the exchange for CR, CT, NMR, angiography, sonography and so on. With its spreading, with the increasing amount of sources included, data volume is increasing, too. This affects storage and traffic. While for long-time storage data compression is generally not accepted at the moment, there are many situations where data compression is possible: Telemedicine for educational purposes (e.g. students at home using low speed internet connections), presentations with standard-resolution video projectors, or even the supply on wards combined receiving written findings. DICOM comprises compression: for still image there is JPEG, for video MPEG-2 is adopted. Within the last years MPEG-2 has been evolved to MPEG-4, which squeezes data even better, but the risk of significant errors increases, too. Within the last years effects of compression have been analyzed for entertainment movies, but these are not comparable to videos of physical examinations (e.g. echocardiography). In medical videos an individual image plays a more important role. Erroneous single images affect total quality even more. Additionally, the effect of compression can not be generalized from one test series to all videos. The result depends strongly on the source. Some investigations have been presented, where different MPEG-4 algorithms compressed videos have been compared and rated manually. But they describe only the results in an elected testbed. In this paper some methods derived from video rating are presented and discussed for an automatically created quality control for the compression of medical videos, primary stored in DICOM containers.

  18. EDICAM fast video diagnostic installation on the COMPASS tokamak

    International Nuclear Information System (INIS)

    Szappanos, A.; Berta, M.; Hron, M.; Panek, R.; Stoeckel, J.; Tulipan, S.; Veres, G.; Weinzettl, V.; Zoletnik, S.

    2010-01-01

    A new camera system 'event detection intelligent camera' (EDICAM) is being developed by the Hungarian Association and has been installed on the COMPASS tokamak in the Institute of Plasma Physics AS CR in Prague, during February 2009. The standalone system contains a data acquisition PC and a prototype sensor module of EDICAM. Appropriate optical system have been designed and adjusted for the local requirements, and a mechanical holder keeps the camera out of the magnetic field. The fast camera contains a monochrome CMOS sensor with advanced control features and spectral sensitivity in the visible range. A special web based control interface has been implemented using Java spring framework to provide the control features in a graphical user environment. Java native interface (JNI) is used to reach the driver functions and to collect the data stored by direct memory access (DMA). Using a built in real-time streaming server one can see the live video from the camera through any web browser in the intranet. The live video is distributed in a Motion Jpeg format using real-time streaming protocol (RTSP) and a Java applet have been written to show the movie on the client side. The control system contains basic image processing features and the 3D wireframe of the tokamak can be projected to the selected frames. A MatLab interface is also presented with advanced post processing and analysis features to make the raw data available for high level computing programs. In this contribution all the concepts of EDICAM control center and the functions of the distinct software modules are described.

  19. Basic quality control in diagnostic radiology

    International Nuclear Information System (INIS)

    Wikstrom, Erik

    2016-01-01

    Along the route toward regular performance of Quality Control in the Diagnostic Imaging sector there are a number of balances to negotiate: Patient/Staff safety considerations vs Regulatory compliance vs Performance of modern equipment vs Clinic's Productivity. At first glance these ambitions may seem in conflict. The tests performed to meet regulatory requirements may or may not bear any semblance to real clinical measurement scenarios. And the process of collecting the data from the quality assurance tests may induce a system down- time that adversely affects the clinic's overall productivity. Furthermore, the time it takes to complete the analysis of the test data and provide the report required to take the facility back into operation is time wasted for patients waiting for a diagnostic imaging exam

  20. Weighted-MSE based on saliency map for assessing video quality of H.264 video streams

    Science.gov (United States)

    Boujut, H.; Benois-Pineau, J.; Hadar, O.; Ahmed, T.; Bonnet, P.

    2011-01-01

    Human vision system is very complex and has been studied for many years specifically for purposes of efficient encoding of visual, e.g. video content from digital TV. There have been physiological and psychological evidences which indicate that viewers do not pay equal attention to all exposed visual information, but only focus on certain areas known as focus of attention (FOA) or saliency regions. In this work, we propose a novel based objective quality assessment metric, for assessing the perceptual quality of decoded video sequences affected by transmission errors and packed loses. The proposed method weights the Mean Square Error (MSE), Weighted-MSE (WMSE), according to the calculated saliency map at each pixel. Our method was validated trough subjective quality experiments.

  1. Video Quality Assessment and Machine Learning: Performance and Interpretability

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Forchhammer, Søren; Korhonen, Jari

    2015-01-01

    In this work we compare a simple and a complex Machine Learning (ML) method used for the purpose of Video Quality Assessment (VQA). The simple ML method chosen is the Elastic Net (EN), which is a regularized linear regression model and easier to interpret. The more complex method chosen is Support...

  2. [Diagnostic bronchoscopy: contribution of the flexible video endoscopy].

    Science.gov (United States)

    Labbé, A

    2007-12-01

    The author describes the use of paediatric flexible videobronchoscopy. Examinations were performed in newborn, infant and child. In neonatal period, the technique is used for the diagnostic of congenital malformation of airway, upper airway obstruction, pre operative evaluation of tracheooesophageal fistula. In children, more frequent indications are airway obstruction with non clear cause, stridor, chronic cough, congenital malformation of airway, tracheomalacia, follow-up of lung transplantation. In intensive care unit, this technique is very useful in the cases of atelectasis, stridor post extubation, follow-up in prolonged intubation and tracheotomy. The possibility of direct visualization of the anomalies in screen and the function of numeric record are important for diagnosis and teaching procedure.

  3. Impact of Constant Rate Factor on Objective Video Quality Assessment

    Directory of Open Access Journals (Sweden)

    Juraj Bienik

    2017-01-01

    Full Text Available This paper deals with the impact of constant rate factor value on the objective video quality assessment using PSNR and SSIM metrics. Compression efficiency of H.264 and H.265 codecs defined by different Constant rate factor (CRF values was tested. The assessment was done for eight types of video sequences depending on content for High Definition (HD, Full HD (FHD and Ultra HD (UHD resolution. Finally, performance of both mentioned codecs with emphasis on compression ratio and efficiency of coding was compared.

  4. Operation quality assessment model for video conference system

    Science.gov (United States)

    Du, Bangshi; Qi, Feng; Shao, Sujie; Wang, Ying; Li, Weijian

    2018-01-01

    Video conference system has become an important support platform for smart grid operation and management, its operation quality is gradually concerning grid enterprise. First, the evaluation indicator system covering network, business and operation maintenance aspects was established on basis of video conference system's operation statistics. Then, the operation quality assessment model combining genetic algorithm with regularized BP neural network was proposed, which outputs operation quality level of the system within a time period and provides company manager with some optimization advice. The simulation results show that the proposed evaluation model offers the advantages of fast convergence and high prediction accuracy in contrast with regularized BP neural network, and its generalization ability is superior to LM-BP neural network and Bayesian BP neural network.

  5. A Video Quality Assessment Method for VoIP Applications Based on User Experience

    Science.gov (United States)

    Wang, Zedong; Wang, Jing; Wang, Fei; Li, Chengcai; Fei, Zesong; Rahim, Tariq

    2017-12-01

    An objective video quality assessment method is proposed to evaluate the video quality in voice over internet protocol (VoIP) applications under network distortion. The fluency and the clarity of videos are two main parts of the factors that affect user experience, thus the method evaluates these two parts to assess the distortions of videos in VoIP applications caused by codec and packet loss. The clarity of the video is measured by calculating block artifacts and frame blurring. Video blocking artifacts are measured by splitting the picture into small blocks and calculating the difference of the pixels around each border while video blurring is measured by getting edge information through Sobel operator, and counting the gradient histogram. Then the video clarity can be measured by a weighted sum of block artifacts score and blurring score using linear regression. The scores are also normalized in order to eliminate the impact of different video contents. The video fluency is calculated by counting the wrong frame in the video. Finally, a weighted sum of video clarity score and video fluency score can represent the quality of the video. The experimental results show that the objective quality scores have a strong correlation with the subjective quality scores, and the algorithm concludes two parts of user experience other than just image quality, which is more comprehensive and it can be used in video quality assessment in VoIP applications.

  6. Objective video quality assessment method for freeze distortion based on freeze aggregation

    Science.gov (United States)

    Watanabe, Keishiro; Okamoto, Jun; Kurita, Takaaki

    2006-01-01

    With the development of the broadband network, video communications such as videophone, video distribution, and IPTV services are beginning to become common. In order to provide these services appropriately, we must manage them based on subjective video quality, in addition to designing a network system based on it. Currently, subjective quality assessment is the main method used to quantify video quality. However, it is time-consuming and expensive. Therefore, we need an objective quality assessment technology that can estimate video quality from video characteristics effectively. Video degradation can be categorized into two types: spatial and temporal. Objective quality assessment methods for spatial degradation have been studied extensively, but methods for temporal degradation have hardly been examined even though it occurs frequently due to network degradation and has a large impact on subjective quality. In this paper, we propose an objective quality assessment method for temporal degradation. Our approach is to aggregate multiple freeze distortions into an equivalent freeze distortion and then derive the objective video quality from the equivalent freeze distortion. Specifically, our method considers the total length of all freeze distortions in a video sequence as the length of the equivalent single freeze distortion. In addition, we propose a method using the perceptual characteristics of short freeze distortions. We verified that our method can estimate the objective video quality well within the deviation of subjective video quality.

  7. Subjective quality assessment of an adaptive video streaming model

    Science.gov (United States)

    Tavakoli, Samira; Brunnström, Kjell; Wang, Kun; Andrén, Börje; Shahid, Muhammad; Garcia, Narciso

    2014-01-01

    With the recent increased popularity and high usage of HTTP Adaptive Streaming (HAS) techniques, various studies have been carried out in this area which generally focused on the technical enhancement of HAS technology and applications. However, a lack of common HAS standard led to multiple proprietary approaches which have been developed by major Internet companies. In the emerging MPEG-DASH standard the packagings of the video content and HTTP syntax have been standardized; but all the details of the adaptation behavior are left to the client implementation. Nevertheless, to design an adaptation algorithm which optimizes the viewing experience of the enduser, the multimedia service providers need to know about the Quality of Experience (QoE) of different adaptation schemes. Taking this into account, the objective of this experiment was to study the QoE of a HAS-based video broadcast model. The experiment has been carried out through a subjective study of the end user response to various possible clients' behavior for changing the video quality taking different QoE-influence factors into account. The experimental conclusions have made a good insight into the QoE of different adaptation schemes which can be exploited by HAS clients for designing the adaptation algorithms.

  8. Video-assisted pericardioscopy. How to improve diagnostic efficacy in pericardial effusions

    Directory of Open Access Journals (Sweden)

    Paulo M. Pêgo-Fernandes

    2001-11-01

    Full Text Available OBJECTIVE: To assess, in a prospective way, the experience with video-assisted pericardioscopy obtained in patients with pericardial effusion of unclear etiology in the preoperative period. METHODS: From January 1998 to June 2000, 20 patients were operated upon with the aid of video-assisted pericardioscopy. On echocardiography, 17 of these patients had significant pericardial effusion, and 3 had moderate pericardial effusion. Video-assisted pericardioscopy was performed through a small incision of the Marfan type. RESULTS: The diagnosis of pericardial effusion was established as follows: idiopathic in 9 (45% patients, neoplastic in 4 (20%, resulting from hypothyroidism in 3 (15%, tuberculous in 2 (10%, due to cholesterol in 1 (5%, and chylopericardial in 1 (5%. The biopsy was positive in 30% of the patients, and the etiology could not be defined in 45% of the patients. CONCLUSION: Video-assisted pericardioscopy proved to be a method with low morbidity and a high index of diagnostic positivity. A high percentage of pericardial effusions are caused by viral infections, which are not diagnosed through current methods, being, therefore, classified as idiopathic.

  9. Video-Quality Estimation Based on Reduced-Reference Model Employing Activity-Difference

    Science.gov (United States)

    Yamada, Toru; Miyamoto, Yoshihiro; Senda, Yuzo; Serizawa, Masahiro

    This paper presents a Reduced-reference based video-quality estimation method suitable for individual end-user quality monitoring of IPTV services. With the proposed method, the activity values for individual given-size pixel blocks of an original video are transmitted to end-user terminals. At the end-user terminals, the video quality of a received video is estimated on the basis of the activity-difference between the original video and the received video. Psychovisual weightings and video-quality score adjustments for fatal degradations are applied to improve estimation accuracy. In addition, low-bit-rate transmission is achieved by using temporal sub-sampling and by transmitting only the lower six bits of each activity value. The proposed method achieves accurate video quality estimation using only low-bit-rate original video information (15kbps for SDTV). The correlation coefficient between actual subjective video quality and estimated quality is 0.901 with 15kbps side information. The proposed method does not need computationally demanding spatial and gain-and-offset registrations. Therefore, it is suitable for real-time video-quality monitoring in IPTV services.

  10. Regulation and quality evaluation system for HIV diagnostics in China.

    Science.gov (United States)

    Xu, Sihong; Huang, Weijin; Zhang, Li; An, Juanjuan; Li, Xiuhua; Song, Aijing; Nie, Jianhui; Zhang, Chuntao; Wang, Youchun

    2016-03-01

    A sophisticated regulatory framework has been constructed for Human immunodeficiency virus (HIV) diagnostics in China, which have developed over the past 30 years. China National Institutes for Food and Drug Control acts as the legal institution in this regulatory framework, launching important activities to ensure the quality of HIV diagnostics. These include the analysis of the main problems faced in developing domestic HIV diagnostics, by investigating the quality of HIV diagnostics and their development; exploring the key factors affecting the quality of HIV diagnostics, to determine the criteria for screening national reference samples; the development of new technologies and methods for preparing reference samples; and the establishment of nine types of national reference panels and nine national standards to evaluate the quality of HIV diagnostics. Based on these researches, a quality evaluation system was established, including nine types of national reference panels, nine national standards for HIV diagnostics, and five sample banks (HIV-positive sample bank, HIV-negative sample bank, common international genotype sample bank, seroconversion series sample bank, HIV virus bank) to evaluate the quality of HIV diagnostics in China. The regulatory framework and the quality evaluation system are pivotal in ensuring the quality of the HIV diagnostics licensed in China. Copyright © 2016 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  11. An Energy-Efficient and High-Quality Video Transmission Architecture in Wireless Video-Based Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yasaman Samei

    2008-08-01

    Full Text Available Technological progress in the fields of Micro Electro-Mechanical Systems (MEMS and wireless communications and also the availability of CMOS cameras, microphones and small-scale array sensors, which may ubiquitously capture multimedia content from the field, have fostered the development of low-cost limited resources Wireless Video-based Sensor Networks (WVSN. With regards to the constraints of videobased sensor nodes and wireless sensor networks, a supporting video stream is not easy to implement with the present sensor network protocols. In this paper, a thorough architecture is presented for video transmission over WVSN called Energy-efficient and high-Quality Video transmission Architecture (EQV-Architecture. This architecture influences three layers of communication protocol stack and considers wireless video sensor nodes constraints like limited process and energy resources while video quality is preserved in the receiver side. Application, transport, and network layers are the layers in which the compression protocol, transport protocol, and routing protocol are proposed respectively, also a dropping scheme is presented in network layer. Simulation results over various environments with dissimilar conditions revealed the effectiveness of the architecture in improving the lifetime of the network as well as preserving the video quality.

  12. Applicability of Existing Objective Metrics of Perceptual Quality for Adaptive Video Streaming

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Krasula, Lukás; Shahid, Muhammad

    2016-01-01

    Objective video quality metrics are designed to estimate the quality of experience of the end user. However, these objective metrics are usually validated with video streams degraded under common distortion types. In the presented work, we analyze the performance of published and known full......-reference and noreference quality metrics in estimating the perceived quality of adaptive bit-rate video streams knowingly out of scope. Experimental results indicate not surprisingly that state of the art objective quality metrics overlook the perceived degradations in the adaptive video streams and perform poorly...

  13. Quality control for diagnostic oral microbiology laboratories in European countries

    NARCIS (Netherlands)

    Rautemaa-Richardson, R.; van der Reijden, W.A.; Dahlen, G.; Smith, A.J.

    2011-01-01

    Participation in diagnostic microbiology internal and external quality control (QC) processes is good laboratory practice and an essential component of a quality management system. However, no QC scheme for diagnostic oral microbiology existed until 2009 when the Clinical Oral Microbiology (COMB)

  14. The video fluorescent device for diagnostics of cancer of human reproductive system

    Science.gov (United States)

    Brysin, Nickolay N.; Linkov, Kirill G.; Stratonnikov, Alexander A.; Savelieva, Tatiana A.; Loschenov, Victor B.

    2008-06-01

    Photodynamic therapy (PDT) is one of the advanced methods of treatment of skin cancer and surfaces of internal organs. The basic advantages of PDT are high efficiency and low cost of treatment. PDT technique is needed for providing fluorescent diagnostics. Laser-based systems are widely applied to the fluorescence excitations for diagnostic because of a narrow spectrum of fluorescence excitation and high density of radiation. Application of laser systems for carrying out fluorescent diagnostics gives the image of a tumor distorted by speckles that does not give an opportunity to obtain full information about the form of a tumor quickly. Besides, these laser excitation systems have complicated structure and high cost. As a base for the development and creation of a video fluorescent device one of commercially produced colposcopes was chosen. It allows to decrease cost of the device, and also has enabled to make modernization for already used colposcopes. A LED-based light source was offered to be used for fluorescence excitation in this work. The maximum in a spectrum of radiation of LEDs corresponds to the general spectral maximum of protoporphyrin IX (PPIX) absorption. Irradiance in the center of a light spot is 31 mW/cm2. The receiving optical system of the fluorescent channel is adjusted at 635 nm where a general spectral maximum of fluorescence PPIX is located. Also the device contains a RGB video channel, a white light source and a USB spectrometer LESA-01-BIOSPEC, for measurement of spectra of fluorescence and diffusion reflections in treatment area. The software is developed for maintenance of the device. Some studies on laboratory animals were made. As a result, areas with the increased concentration of a PPIX were correctly detected. At present, the device is used for diagnostics of cancer of female reproductive system in Research Centre for Obstetrics, Gynecology and Perinatology of the Russian Academy of Medical Sciences (Moscow, Russia).

  15. Degraded visual environment image/video quality metrics

    Science.gov (United States)

    Baumgartner, Dustin D.; Brown, Jeremy B.; Jacobs, Eddie L.; Schachter, Bruce J.

    2014-06-01

    A number of image quality metrics (IQMs) and video quality metrics (VQMs) have been proposed in the literature for evaluating techniques and systems for mitigating degraded visual environments. Some require both pristine and corrupted imagery. Others require patterned target boards in the scene. None of these metrics relates well to the task of landing a helicopter in conditions such as a brownout dust cloud. We have developed and used a variety of IQMs and VQMs related to the pilot's ability to detect hazards in the scene and to maintain situational awareness. Some of these metrics can be made agnostic to sensor type. Not only are the metrics suitable for evaluating algorithm and sensor variation, they are also suitable for choosing the most cost effective solution to improve operating conditions in degraded visual environments.

  16. On the definition of adapted audio/video profiles for high-quality video calling services over LTE/4G

    Science.gov (United States)

    Ndiaye, Maty; Quinquis, Catherine; Larabi, Mohamed Chaker; Le Lay, Gwenael; Saadane, Hakim; Perrine, Clency

    2014-01-01

    During the last decade, the important advances and widespread availability of mobile technology (operating systems, GPUs, terminal resolution and so on) have encouraged a fast development of voice and video services like video-calling. While multimedia services have largely grown on mobile devices, the generated increase of data consumption is leading to the saturation of mobile networks. In order to provide data with high bit-rates and maintain performance as close as possible to traditional networks, the 3GPP (The 3rd Generation Partnership Project) worked on a high performance standard for mobile called Long Term Evolution (LTE). In this paper, we aim at expressing recommendations related to audio and video media profiles (selection of audio and video codecs, bit-rates, frame-rates, audio and video formats) for a typical video-calling services held over LTE/4G mobile networks. These profiles are defined according to targeted devices (smartphones, tablets), so as to ensure the best possible quality of experience (QoE). Obtained results indicate that for a CIF format (352 x 288 pixels) which is usually used for smartphones, the VP8 codec provides a better image quality than the H.264 codec for low bitrates (from 128 to 384 kbps). However sequences with high motion, H.264 in slow mode is preferred. Regarding audio, better results are globally achieved using wideband codecs offering good quality except for opus codec (at 12.2 kbps).

  17. [Diagnostic yield of video capsule endoscopy in premenopausal women with iron-deficiency anemia].

    Science.gov (United States)

    Garrido Durán, Carmen; Iyo Miyashiro, Eduardo; Páez Cumpa, Claudia; Khorrami Minaei, Sam; Erimeiku Barahona, Alicia; Llompart Rigo, Alfredo

    2015-01-01

    Clinical practice guidelines recommend video capsule endoscopy (VCE) studies in patients with iron-deficiency anemia (IDA) after conventional upper and lower endoscopies but there is a need for studies demonstrating the diagnostic yield, clinical impact, and cost in some patient subgroups. 1.To determine the diagnostic yield of VCE in premenopausal women with IDA compared with that in men and postmenopausal women. 2. To identify the presence of VCE predictors in premenopausal women. 3. To estimate the cost-clinical impact relationship associated with VCE in this indication. We retrospectively analyzed 408 patients who underwent VCE. Patients with IDA were enrolled (premenopausal, postmenopausal women, and men), with previous normal work-up by conventional endoscopies. A total of 249 patients were enrolled: 131 women (52.6%), of which 51 were premenopausal and 80 were post-menopausal, and 118 men. The mean age was 60.7±16 years. The diagnostic yield of VCE for the diagnosis of IDA was 44.6% (95% CI 39.9 - 50.8). Diagnostic yield was 50.8% vs 38.9% in men vs women (p=0.05) and was 55% vs 13.7% in postmenopausal vs premenopausal women (p<0.001). No predictors of small bowel lesions were found in premenopausal women. The most common findings in the postmenopausal group were angioectasias (70.5%) and erosions (57.1%) in the premenopausal group. The cost in premenopausal women was 44.727€ and 86.3% of the procedures had no clinical impact. The diagnostic yield of VCE is low in the etiological study of IDA in premenopausal women and there is no cost-effectiveness in relation to clinical impact. No predictors of small bowel lesions were found in this group. Copyright © 2015 Elsevier España, S.L.U. and AEEH y AEG. All rights reserved.

  18. A reduced-reference perceptual image and video quality metric based on edge preservation

    Science.gov (United States)

    Martini, Maria G.; Villarini, Barbara; Fiorucci, Federico

    2012-12-01

    In image and video compression and transmission, it is important to rely on an objective image/video quality metric which accurately represents the subjective quality of processed images and video sequences. In some scenarios, it is also important to evaluate the quality of the received video sequence with minimal reference to the transmitted one. For instance, for quality improvement of video transmission through closed-loop optimisation, the video quality measure can be evaluated at the receiver and provided as feedback information to the system controller. The original image/video sequence--prior to compression and transmission--is not usually available at the receiver side, and it is important to rely at the receiver side on an objective video quality metric that does not need reference or needs minimal reference to the original video sequence. The observation that the human eye is very sensitive to edge and contour information of an image underpins the proposal of our reduced reference (RR) quality metric, which compares edge information between the distorted and the original image. Results highlight that the metric correlates well with subjective observations, also in comparison with commonly used full-reference metrics and with a state-of-the-art RR metric.

  19. On the performance of video quality assessment metrics under different compression and packet loss scenarios.

    Science.gov (United States)

    Martínez-Rach, Miguel O; Piñol, Pablo; López, Otoniel M; Perez Malumbres, Manuel; Oliver, José; Calafate, Carlos Tavares

    2014-01-01

    When comparing the performance of video coding approaches, evaluating different commercial video encoders, or measuring the perceived video quality in a wireless environment, Rate/distortion analysis is commonly used, where distortion is usually measured in terms of PSNR values. However, PSNR does not always capture the distortion perceived by a human being. As a consequence, significant efforts have focused on defining an objective video quality metric that is able to assess quality in the same way as a human does. We perform a study of some available objective quality assessment metrics in order to evaluate their behavior in two different scenarios. First, we deal with video sequences compressed by different encoders at different bitrates in order to properly measure the video quality degradation associated with the encoding system. In addition, we evaluate the behavior of the quality metrics when measuring video distortions produced by packet losses in mobile ad hoc network scenarios with variable degrees of network congestion and node mobility. Our purpose is to determine if the analyzed metrics can replace the PSNR while comparing, designing, and evaluating video codec proposals, and, in particular, under video delivery scenarios characterized by bursty and frequent packet losses, such as wireless multihop environments.

  20. The role of optical flow in automated quality assessment of full-motion video

    Science.gov (United States)

    Harguess, Josh; Shafer, Scott; Marez, Diego

    2017-09-01

    In real-world video data, such as full-motion-video (FMV) taken from unmanned vehicles, surveillance systems, and other sources, various corruptions to the raw data is inevitable. This can be due to the image acquisition process, noise, distortion, and compression artifacts, among other sources of error. However, we desire methods to analyze the quality of the video to determine whether the underlying content of the corrupted video can be analyzed by humans or machines and to what extent. Previous approaches have shown that motion estimation, or optical flow, can be an important cue in automating this video quality assessment. However, there are many different optical flow algorithms in the literature, each with their own advantages and disadvantages. We examine the effect of the choice of optical flow algorithm (including baseline and state-of-the-art), on motionbased automated video quality assessment algorithms.

  1. Non-intrusive Packet-Layer Model for Monitoring Video Quality of IPTV Services

    Science.gov (United States)

    Yamagishi, Kazuhisa; Hayashi, Takanori

    Developing a non-intrusive packet-layer model is required to passively monitor the quality of experience (QoE) during service. We propose a packet-layer model that can be used to estimate the video quality of IPTV using quality parameters derived from transmitted packet headers. The computational load of the model is lighter than that of the model that takes video signals and/or video-related bitstream information such as motion vectors as input. This model is applicable even if the transmitted bitstream information is encrypted because it uses transmitted packet headers rather than bitstream information. For developing the model, we conducted three extensive subjective quality assessments for different encoders and decoders (codecs), and video content. Then, we modeled the subjective video quality assessment characteristics based on objective features affected by coding and packet loss. Finally, we verified the model's validity by applying our model to unknown data sets different from training data sets used above.

  2. Chroma Subsampling Influence on the Perceived Video Quality for Compressed Sequences in High Resolutions

    Directory of Open Access Journals (Sweden)

    Miroslav Uhrina

    2017-01-01

    Full Text Available This paper deals with the influence of chroma subsampling on perceived video quality measured by subjective metrics. The evaluation was done for two most used video codecs H.264/AVC and H.265/HEVC. Eight types of video sequences with Full HD and Ultra HD resolutions depending on content were tested. The experimental results showed that observers did not see the difference between unsubsampled and subsampled sequences, so using subsampled videos is preferable even 50 % of the amount of data can be saved. Also, the minimum bitrates to achieve the good and fair quality by each codec and resolution were determined.

  3. Summarization of Surveillance Video Sequences Using Face Quality Assessment

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Moeslund, Thomas B.; Rahmati, Mohammad

    2011-01-01

    Constant working surveillance cameras in public places, such as airports and banks, produce huge amount of video data. Faces in such videos can be extracted in real time. However, most of these detected faces are either redundant or useless. Redundant information adds computational costs to facial...... technique for this purpose. The summarized results of this technique have been used in three different facial analysis systems and the experimental results on real video sequences are promising....

  4. Quality Control in Diagnostic Radiology in the Netherlands (invited paper)

    International Nuclear Information System (INIS)

    Zoetelief, J.

    1998-01-01

    Application of the general principles of radiation protection to medical diagnostic radiology implies that each procedure using X rays or radionuclides is to be justified and optimised. Optimisation in diagnostic radiology implies that the radiation burden to the patient should be as low as possible, but compatible with the image quality necessary to obtain an adequate diagnosis or to guide treatment. Quality control of equipment is a prerequisite for achieving optimisation in diagnostic radiology. This was especially recognised for mammography as employed for breast cancer screening. Existing legislation in the Netherlands includes only a few criteria for equipment used in diagnostic radiology. In addition, the criteria are not all operational and measurement methods are lacking. Therefore, upon the initiative of the Dutch Ministry of Health, Welfare and Sports, the relevant professional societies, in collaboration with the former TNO Centre for Radiological Protection and Dosimetry, formulated eleven guidelines for quality control of equipment used in diagnostic radiology, including test procedures, test frequencies and limiting values. The implementation of quality control of equipment was included in the 1984 European Directive (84/466/Euratom) laying down basic measures for the radiation protection of persons undergoing medical examination or treatment. In the most recent European Directive on medical exposure (97/43/Euratom) the importance of quality control is stressed. In addition, the latter EC directive proposes the use of diagnostic reference levels for limiting the risks for patients undergoing diagnostic radiology. In the Netherlands preliminary reference levels for various procedures employed in diagnostic radiology are suggested. Finally, methods applied in the Netherlands for assessment of image quality are discussed. (author)

  5. Diagnosing psychogenic nonepileptic seizures: Video-EEG monitoring, suggestive seizure induction and diagnostic certainty.

    Science.gov (United States)

    Popkirov, Stoyan; Jungilligens, Johannes; Grönheit, Wenke; Wellmer, Jörg

    2017-08-01

    Psychogenic nonepileptic seizures (PNES) can remain undiagnosed for many years, leading to unnecessary medication and delayed treatment. A recent report by the International League Against Epilepsy Nonepileptic Seizures Task Force recommends a staged approach to the diagnosis of PNES (LaFrance, et al., 2013). We aimed to investigate its practical utility, and to apply the proposed classification to evaluate the role of long-term video-EEG monitoring (VEEG) and suggestive seizure induction (SSI) in PNES workup. Using electronic medical records, 122 inpatients (mean age 36.0±12.9years; 68% women) who received the diagnosis of PNES at our epilepsy center during a 4.3-year time period were included. There was an 82.8% agreement between diagnostic certainty documented at discharge and that assigned retroactively using the Task Force recommendations. In a minority of cases, having used the Task Force criteria could have encouraged the clinicians to give more certain diagnoses, exemplifying the Task Force report's utility. Both VEEG and SSI were effective at supporting high level diagnostic certainty. Interestingly, about one in four patients (26.2%) had a non-diagnostic ("negative") VEEG but a positive SSI. On average, this subgroup did not have significantly shorter mean VEEG recording times than VEEG-positive patients. However, VEEG-negative/SSI-positive patients had a significantly lower habitual seizure frequency than their counterparts. This finding emphasizes the utility of SSI in ascertaining the diagnosis of PNES in patients who do not have a spontaneous habitual event during VEEG due to, for example, low seizure frequency. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Quality assurance program on diagnostic radiology

    International Nuclear Information System (INIS)

    Yacovenco, Alejandro; Borges, Jose Carlos; Mota, Helvecio Correa

    1995-01-01

    Aiming to elaborate a methodology to optimize the performance of the Radiology Service of the Military Police Hospital, in Rio de Janeiro, some goals were established: improvement of the attendance to patients; improvement of the qualification of technicians; achievement and maintenance of high degrees of quality in each step of the radiological process; improvement of the image quality; optimization of dose per examination and cost reduction. (author). 8 refs., 3 figs

  7. Predicting Quality Of Experience For Online Video Systems Using Machine Learning

    OpenAIRE

    Dagiuklas, T; Bulkan, U

    2017-01-01

    As the expansion of the online video broadcasting continues in every area of the modern connected world, the need for measuring and predicting the Quality of Experience for content delivery has never been this important. This demo paper has designed and developed a real-time and continuously trained machine learning model in order to predict QoE for online video systems. For this purpose, a platform has been developed where video content is unicasted to a cluster of users simultaneously while...

  8. No-reference video quality measurement: added value of machine learning

    Science.gov (United States)

    Mocanu, Decebal Constantin; Pokhrel, Jeevan; Garella, Juan Pablo; Seppänen, Janne; Liotou, Eirini; Narwaria, Manish

    2015-11-01

    Video quality measurement is an important component in the end-to-end video delivery chain. Video quality is, however, subjective, and thus, there will always be interobserver differences in the subjective opinion about the visual quality of the same video. Despite this, most existing works on objective quality measurement typically focus only on predicting a single score and evaluate their prediction accuracies based on how close it is to the mean opinion scores (or similar average based ratings). Clearly, such an approach ignores the underlying diversities in the subjective scoring process and, as a result, does not allow further analysis on how reliable the objective prediction is in terms of subjective variability. Consequently, the aim of this paper is to analyze this issue and present a machine-learning based solution to address it. We demonstrate the utility of our ideas by considering the practical scenario of video broadcast transmissions with focus on digital terrestrial television (DTT) and proposing a no-reference objective video quality estimator for such application. We conducted meaningful verification studies on different video content (including video clips recorded from real DTT broadcast transmissions) in order to verify the performance of the proposed solution.

  9. No-Reference Video Quality Assessment using MPEG Analysis

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Forchhammer, Søren; Korhonen, Jari

    2013-01-01

    and estimate the video coding parameters for MPEG-2 and H.264/AVC which can be used to improve the VQA. The analysis differs from most other video coding analysis methods since it is without access to the bitstream. The results show that our proposed method is competitive with other recent NR VQA methods...... for MPEG-2 and H.264/AVC....

  10. Quality assurance in diagnostic chest radiography

    International Nuclear Information System (INIS)

    Feuerbach, S.

    1988-01-01

    The quality criteria for standard radiographs of the thorax give measurable parameters for evaluation of X-ray pictures of the thorax. These include (1) Image characteristics that are organ-specific image elements, (2) critical structures that shed light on image characteristics especially important for the diagnosis, and (3) measures of single structures as significant details that give information due to their size. Technical data and requirements complete the criteria, which, however, ought to be applied in combination with a suitable interpretation of the image data in order to achieve good quality control. (orig.) [de

  11. No-Reference Video Quality Assessment Model for Distortion Caused by Packet Loss in the Real-Time Mobile Video Services

    Directory of Open Access Journals (Sweden)

    Jiarun Song

    2014-01-01

    Full Text Available Packet loss will make severe errors due to the corruption of related video data. For most video streams, because the predictive coding structures are employed, the transmission errors in one frame will not only cause decoding failure of itself at the receiver side, but also propagate to its subsequent frames along the motion prediction path, which will bring a significant degradation of end-to-end video quality. To quantify the effects of packet loss on video quality, a no-reference objective quality assessment model is presented in this paper. Considering the fact that the degradation of video quality significantly relies on the video content, the temporal complexity is estimated to reflect the varying characteristic of video content, using the macroblocks with different motion activities in each frame. Then, the quality of the frame affected by the reference frame loss, by error propagation, or by both of them is evaluated, respectively. Utilizing a two-level temporal pooling scheme, the video quality is finally obtained. Extensive experimental results show that the video quality estimated by the proposed method matches well with the subjective quality.

  12. 3D Scan-Based Wavelet Transform and Quality Control for Video Coding

    Directory of Open Access Journals (Sweden)

    Parisot Christophe

    2003-01-01

    Full Text Available Wavelet coding has been shown to achieve better compression than DCT coding and moreover allows scalability. 2D DWT can be easily extended to 3D and thus applied to video coding. However, 3D subband coding of video suffers from two drawbacks. The first is the amount of memory required for coding large 3D blocks; the second is the lack of temporal quality due to the sequence temporal splitting. In fact, 3D block-based video coders produce jerks. They appear at blocks temporal borders during video playback. In this paper, we propose a new temporal scan-based wavelet transform method for video coding combining the advantages of wavelet coding (performance, scalability with acceptable reduced memory requirements, no additional CPU complexity, and avoiding jerks. We also propose an efficient quality allocation procedure to ensure a constant quality over time.

  13. Design of video quality metrics with multi-way data analysis a data driven approach

    CERN Document Server

    Keimel, Christian

    2016-01-01

    This book proposes a data-driven methodology using multi-way data analysis for the design of video-quality metrics. It also enables video- quality metrics to be created using arbitrary features. This data- driven design approach not only requires no detailed knowledge of the human visual system, but also allows a proper consideration of the temporal nature of video using a three-way prediction model, corresponding to the three-way structure of video. Using two simple example metrics, the author demonstrates not only that this purely data- driven approach outperforms state-of-the-art video-quality metrics, which are often optimized for specific properties of the human visual system, but also that multi-way data analysis methods outperform the combination of two-way data analysis methods and temporal pooling. .

  14. Quality Assessment of Adaptive Bitrate Videos using Image Metrics and Machine Learning

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Forchhammer, Søren; Brunnström, Kjell

    2015-01-01

    Adaptive bitrate (ABR) streaming is widely used for distribution of videos over the internet. In this work, we investigate how well we can predict the quality of such videos using well-known image metrics, information about the bitrate levels, and a relatively simple machine learning method...

  15. Quality assurance programme in diagnostic radiology

    International Nuclear Information System (INIS)

    Yacovenco, A.A.

    1996-01-01

    One hundred years after the discovery of X-rays, they continue being nowadays part of physicians' daily activities, and the diagnosis through the use of X-ray equipment is one of the most important fields in clinical medicine, thus becoming the most important cause of human exposure to artificial sources. For this reason, in the last twenty years, most of the developed countries did the utmost to establish programs which could warrant the quality of the radiographic image. Aiming the protection of human being against the harmful effects of ionizing radiations, in December 1980, World Health Organization decided to form a group of professionals highly experienced in medical radiology, and initiate an inspection and quality control program. In September 1988, the Group of Studies of the Program Related to Radiological Protection of the Commission in the European Communities, prepared a working paper in which guidelines were set up regarding quality of images, dosage to patient, and associated radiographic factors, necessary to obtain acceptable radiologic performance. In Brazil, efforts driven in this direction, guided by some equipment testing, starting in 1990, began to be more known. When the Director and the Head of Radiology in the Military Police Hospital of the State of Rio de Janeiro (HPM) reamed about these efforts, they decided to contact the Institute for Radioprotection and Dosimetry (IRD) of Comissao Nacional de Energia Nuclear and submit the problem of low radiologic performance and increasing rates of rejection. Thus, with the coincidence of interests and needs, along with a proposal from the Commission of the European Communities (CEC), IRD decided to offer the author laboratory support to elaborate a Quality Assurance Program (QAP) to be implemented in HPM. (author)

  16. Quality control in diagnostic radiology: experience and challenges

    International Nuclear Information System (INIS)

    Abd Aziz Mhd Ramli; Mohd Ramli Arshad; Mohd Khalid Matori; Muhammad Jamal Md Isa; Husaini Salleh; Abdullah Tahir Aliyasak; Zainal Jamaluddin; Hasrul Hisham Hussain

    2005-01-01

    Malaysian Institute for Nuclear Technology Research through its Medical Physics Group has been providing Quality Control (QC) services for medical x-ray apparatus used in diagnostic radiology to private clinics and hospitals since the year 1997. The quality control (QC) in diagnostic radiology is considered as part of quality assurance program which provide accurate diagnostic information at the lowest cost and the least exposure of the patients to radiation. Many experience and obstacles were faced by Medical Physics Group. This paper will discuss on some of the experiences and challenges that could be shared together with MINT staff especially in the safety aspect related to electrical and mechanical, radiation protection, performance and standard. The challenging in administrative aspect also will discuss. (Author)

  17. Quality assurance program in diagnostic radiology

    International Nuclear Information System (INIS)

    Yacovenco, Alejandro; Borges, J.C.

    1994-01-01

    Aiming to elaborate a methodology to optimize the performance of the Radiology Service of the Military Police Hospital, in Rio dee Janeiro, some goals were established: improvement of the attendance to patients; improvement of the qualification of technicians; achievement and maintenance of high degrees of quality in each step of the radiological process; improvement of the image quality; optimization of dose per examination and cost reduction. The procedure used to detect faults in the radiological process was the analysis of causes of film losses. Results show a 70% reduction in the film rejection rate. 74% of total identified faults were due to equipment, 11% to films, 10% to patients and 5% to developing. The reduction in the cost of developed film reached 75%. A training course given to the staff of the radiological service fully reached its goals, contributing, with the staff motivation, mostly to the success of the program. This success indicates that, with a serious persistent work, it is possible to offer to patients services within their expectations, even at a public hospital. Such programs should be supported by health authorities, not only due to their technical and economic needs but, mostly, due to their social implications. (author). 10 refs., 11 figs

  18. Impact of microcirculatory video quality on the evaluation of sublingual microcirculation in critically ill patients.

    Science.gov (United States)

    Damiani, Elisa; Ince, Can; Scorcella, Claudia; Domizi, Roberta; Carsetti, Andrea; Mininno, Nicoletta; Pierantozzi, Silvia; Adrario, Erica; Romano, Rocco; Pelaia, Paolo; Donati, Abele

    2017-10-01

    We aimed to assess the impact of image quality on microcirculatory evaluation with sidestream dark-field (SDF) videomicroscopy in critically ill patients and explore factors associated with low video quality. This was a retrospective analysis of a single-centre prospective observational study. Videos of the sublingual microcirculation were recorded using SDF videomicroscopy in 100 adult patients within 12 h from admittance to the intensive care unit and every 24 h until discharge/death. Parameters of vessel density and perfusion were calculated offline for small vessels. For all videos, a quality score (-12 = unacceptable, 1 = suboptimal, 2 = optimal) was assigned for brightness, focus, content, stability, pressure and duration. Videos with a total score ≤8 were deemed as unacceptable. A total of 2455 videos (853 triplets) was analysed. Quality was acceptable in 56 % of videos. Lower quality was associated with worse microvascular density and perfusion. Unreliable triplets (≥1 unacceptable or missing video, 65 % of total) showed lower vessel density, worse perfusion and higher flow heterogeneity as compared to reliable triplets (p Quality was higher among triplets collected by an extensively-experienced investigator or in patients receiving sedation or mechanical ventilation. Perfused vessel density was higher in patients with Glasgow Coma Scale (GCS) ≤8 (18.9 ± 4.5 vs. 17.0 ± 3.9 mm/mm 2 in those with GCS >8, p quality depends on both the operator's experience and patient's cooperation. Low-quality videos may produce spurious data, leading to an overestimation of microvascular alterations.

  19. A randomized controlled trial of an educational video to improve quality of bowel preparation for colonoscopy.

    Science.gov (United States)

    Park, Jin-Seok; Kim, Min Su; Kim, HyungKil; Kim, Shin Il; Shin, Chun Ho; Lee, Hyun Jung; Lee, Won Seop; Moon, Soyoung

    2016-06-17

    High-quality bowel preparation is necessary for colonoscopy. A few studies have been conducted to investigate improvement in bowel preparation quality through patient education. However, the effect of patient education on bowel preparation has not been well studied. A randomized and prospective study was conducted. All patients received regular instruction for bowel preparation during a pre-colonoscopy visit. Those scheduled for colonoscopy were randomly assigned to view an educational video instruction (video group) on the day before the colonoscopy, or to a non-video (control) group. Qualities of bowel preparation using the Ottawa Bowel Preparation Quality scale (Ottawa score) were compared between the video and non-video groups. In addition, factors associated with poor bowel preparation were investigated. A total of 502 patients were randomized, 250 to the video group and 252 to the non-video group. The video group exhibited better bowel preparation (mean Ottawa total score: 3.03 ± 1.9) than the non-video group (4.21 ± 1.9; P preparation for colonoscopy (total Ottawa score 2.79, P = 0.021), and non-use of visual aids (OR = 3.09, P preparation. In the comparison of the colonoscopic outcomes between groups, the polyp detection rate was not significantly different between video group and non-video group (48/250, 19.2 % vs. 48/252, 19.0 %; P = 0.963), but insertion time was significantly short in video group (5.5 ± 3.2 min) than non-video group (6.1 ± 3.7 min; P = 0.043). The addition of an educational video could improve the quality of bowel preparation in comparison with standard preparation method. Clinical Research Information Service KCT0001836 . The date of registration: March, 08(th), 2016, Retrospectively registered.

  20. Quality versus intelligibility: studying human preferences for American Sign Language video

    Science.gov (United States)

    Ciaramello, Frank M.; Hemami, Sheila S.

    2011-03-01

    Real-time videoconferencing using cellular devices provides natural communication to the Deaf community. For this application, compressed American Sign Language (ASL) video must be evaluated in terms of the intelligibility of the conversation and not in terms of the overall aesthetic quality of the video. This work presents a paired comparison experiment to determine the subjective preferences of ASL users in terms of the trade-off between intelligibility and quality when varying the proportion of the bitrate allocated explicitly to the regions of the video containing the signer. A rate-distortion optimization technique, which jointly optimizes a quality criteria and an intelligibility criteria according to a user-specified parameter, generates test video pairs for the subjective experiment. Experimental results suggest that at sufficiently high bitrates, all users prefer videos in which the non-signer regions in the video are encoded with some nominal rate. As the total encoding bitrate decreases, users generally prefer video in which a greater proportion of the rate is allocated to the signer. The specific operating points preferred in the quality-intelligibility trade-off vary with the demographics of the users.

  1. Characterization of radiation qualities used in diagnostic X-ray

    International Nuclear Information System (INIS)

    Bero, M.; Zahili, M.; Al Ahmad, M.

    2013-12-01

    This study aims to adjust the radiation beams emitted from X-ray tubes installed at the National Radiation Metrology Laboratory in the field of diagnostic radiology (radiology and mammography) according to the IAEA protocol code number TRS 457, the second goal of this study is to establish various radiation qualities used fordiagnostic radiology applications: RQR, RQA and RQT and the radiation qualities related to mammography applications: RQA-M and RQR-M (author).

  2. Perception of quality control by personnel in diagnostic radiology ...

    African Journals Online (AJOL)

    This situation may be due to the perceived lack of interest and lack of cooperation from management of their facilities.The personnel also felt that they did not have sufficient training to implement QC and that QC results were difficult to analyse. Keywords: perception, quality control, personnel, management, diagnostic ...

  3. Optimisation of patient protection and image quality in diagnostic ...

    African Journals Online (AJOL)

    Radiology Department of Kenyatta National Hospital, a referral, teaching and research hospital in Kenya. Subjects: A total of 837 adult and 229 paediatric patients undergoing diagnostic examinations were assessed for patient dose and image quality. Interventions: The X-ray tube output measurements and X-ray exposure ...

  4. The influence of motion quality on responses towards video playback stimuli

    Directory of Open Access Journals (Sweden)

    Emma Ware

    2015-07-01

    Full Text Available Visual motion, a critical cue in communication, can be manipulated and studied using video playback methods. A primary concern for the video playback researcher is the degree to which objects presented on video appear natural to the non-human subject. Here we argue that the quality of motion cues on video, as determined by the video's image presentation rate (IPR, are of particular importance in determining a subject's social response behaviour. We present an experiment testing the effect of variations in IPR on pigeon (Columbia livia response behaviour towards video images of courting opposite sex partners. Male and female pigeons were presented with three video playback stimuli, each containing a different social partner. Each stimulus was then modified to appear at one of three IPRs: 15, 30 or 60 progressive (p frames per second. The results showed that courtship behaviour became significantly longer in duration as IPR increased. This finding implies that the IPR significantly affects the perceived quality of motion cues impacting social behaviour. In males we found that the duration of courtship also depended on the social partner viewed and that this effect interacted with the effects of IPR on behaviour. Specifically, the effect of social partner reached statistical significance only when the stimuli were displayed at 60 p, demonstrating the potential for erroneous results when insufficient IPRs are used. In addition to demonstrating the importance of IPR in video playback experiments, these findings help to highlight and describe the role of visual motion processing in communication behaviour.

  5. Radiological protection and quality control for diagnostic radiology in China

    International Nuclear Information System (INIS)

    Baorong, Yue

    2008-01-01

    Full text: There are 43,000 diagnostic departments, nearly 70,000 X-ray diagnostic facilities, 7,000 CT, 250 million for the annual total numbers of X-ray examinations, 120,000 occupationally exposed workers in diagnostic radiology. 'Basic standards for protection against ionizing radiation and for the safety of radiation sources' is promulgated on October, 2002. This basic standard follows the BSS. 'Rule on the administration of radio-diagnosis and radiotherapy', as a order of the Ministry of Health No. 46, is promulgated by Minister of Health on January 24, 2006. It includes general provisions, requirements and practice, establishment and approval of radio-diagnosis and radiotherapy services, safeguards and quality assurance, and so on. There are a series of radiological protection standards and quality control standards in diagnostic radiology, including 'radiological protection standard for the examination in X-ray diagnosis', 'radiological health protection standards for X-ray examination of child-bearing age women and pregnant women', 'radiological protection standards for the children in X-ray diagnosis', 'standards for radiological protection in medical X-ray diagnosis', 'specification for radiological protection monitoring in medical X-ray diagnosis', 'guide for reasonable application of medical X-ray diagnosis', 'general aspects for quality assurance in medical X-ray image of diagnosis', 'specification of image quality control test for the medical X-ray diagnostic equipment', 'specification of image quality assurance test for X-ray equipment for computed tomography', 'specification for testing of quality control in computed radiography (CR)' and 'specification for testing of quality control in X-ray mammography'. With the X-ray diagnostic equipment, there are acceptant tests, status tests and routing tests in large hospitals. It is poor for routing test in middle and smaller hospitals. CT is used widely in diagnostic radiology, however most workers in CT

  6. Subjective Quality Assessment of H.264/AVC Video Streaming with Packet Losses

    Directory of Open Access Journals (Sweden)

    Naccari Matteo

    2011-01-01

    Full Text Available Research in the field of video quality assessment relies on the availability of subjective scores, collected by means of experiments in which groups of people are asked to rate the quality of video sequences. The availability of subjective scores is fundamental to enable validation and comparative benchmarking of the objective algorithms that try to predict human perception of video quality by automatically analyzing the video sequences, in a way to support reproducible and reliable research results. In this paper, a publicly available database of subjective quality scores and corrupted video sequences is described. The scores refer to 156 sequences at CIF and 4CIF spatial resolutions, encoded with H.264/AVC and corrupted by simulating the transmission over an error-prone network. The subjective evaluation has been performed by 40 subjects at the premises of two academic institutions, in standard-compliant controlled environments. In order to support reproducible research in the field of full-reference, reduced-reference, and no-reference video quality assessment algorithms, both the uncompressed files and the H.264/AVC bitstreams, as well as the packet loss patterns, have been made available to the research community.

  7. A time-varying subjective quality model for mobile streaming videos with stalling events

    Science.gov (United States)

    Ghadiyaram, Deepti; Pan, Janice; Bovik, Alan C.

    2015-09-01

    Over-the-top mobile video streaming is invariably influenced by volatile network conditions which cause playback interruptions (stalling events), thereby impairing users' quality of experience (QoE). Developing models that can accurately predict users' QoE could enable the more efficient design of quality-control protocols for video streaming networks that reduce network operational costs while still delivering high-quality video content to the customers. Existing objective models that predict QoE are based on global video features, such as the number of stall events and their lengths, and are trained and validated on a small pool of ad hoc video datasets, most of which are not publicly available. The model we propose in this work goes beyond previous models as it also accounts for the fundamental effect that a viewer's recent level of satisfaction or dissatisfaction has on their overall viewing experience. In other words, the proposed model accounts for and adapts to the recency, or hysteresis effect caused by a stall event in addition to accounting for the lengths, frequency of occurrence, and the positions of stall events - factors that interact in a complex way to affect a user's QoE. On the recently introduced LIVE-Avvasi Mobile Video Database, which consists of 180 distorted videos of varied content that are afflicted solely with over 25 unique realistic stalling events, we trained and validated our model to accurately predict the QoE, attaining standout QoE prediction performance.

  8. Using DASH assisting network elements for optimizing video streaming quality

    NARCIS (Netherlands)

    J.W.M. Kleinrouweler (Jan Willem)

    2017-01-01

    textabstractOn-demand video streaming is a popular application which accounts for a large share of today's Internet traffic. Dynamic Adaptive Streaming over HTTP (DASH) is the major streaming technology used by large content providers. However, this technology suffers from performance problems when

  9. Diagnostic X-ray imaging quality assurance: an overview

    International Nuclear Information System (INIS)

    Periard, M.A.; Chaloner, P.

    1996-01-01

    A basic diagnostic imaging quality assurance program is a regulatory requirement in many provinces and in federal institutions. An ineffective quality assurance program can lead to poor quality radiograms that can impair diagnosis, increase operating costs and contribute to unnecessary radiation exposure to both patients and staff. Any extension of the basic quality assurance program is the responsibility of each x-ray facility. To achieve maximum benefit, all levels of management and technical staff must support and participate in the operation of a well-defined program. This article outlines the essential aspects of a quality assurance program and is intended to encourage the review of a moderate-sized hospital's x-ray imaging quality assurance procedures. (author)

  10. The european approach to quality assurance in diagnostic radiology

    International Nuclear Information System (INIS)

    Benini, A.

    1997-01-01

    The european and increasingly the international organizations are emphasizing the importance of appropriate quality assurance programmes in diagnostic radiology. The European Directive (particularly the directive 84/466/EURATOM). the various publications of the International Commission for radiation protection (ICRP), related to protection of the patients and workers and the Basic Safety Standards of the International Atomic Energy Agency (IAEA) might be considered the landmarks of the new approach to the problems of dose reduction and quality in diagnostic radiology. In particular ICRP maintains a watching brief on all aspects related to radiation protection and makes recommendations concerning basic principles. Since ICRP 26 (1977), several ICRP publications have dealt with all the principal fields of diagnostic radiology. The IAEA has recently published the new Basic Safety Standards including guidance levels for the most common diagnostic investigations.Within the European countries the European Union and the European legislation have strong influence of the implementation of radiation protection and Q A at a national level. This has led to a substantial effort in the european countries to establish national standards and basic quality requirements. (author)

  11. Capturing and displaying microscopic images used in medical diagnostics and forensic science using 4K video resolution – an application in higher education

    NARCIS (Netherlands)

    Jan Kuijten; Ajda Ortac; Hans Maier; Gert de Heer

    2015-01-01

    To analyze, interpret and evaluate microscopic images, used in medical diagnostics and forensic science, video images for educational purposes were made with a very high resolution of 4096 × 2160 pixels (4K), which is four times as many pixels as High-Definition Video (1920 × 1080 pixels).

  12. National Plant Diagnostic Network, Taxonomic training videos: Introduction to AphID

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides visual instruction on the use of the expert system, AphID, for aphid examination and identification. The video demonstrates the use of different training modules that allow the user to gain familiarity wi...

  13. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Aphis gossypii

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the cotton aphid, Aphis gossypii, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures that ca...

  14. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Myzus persicae

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the green peach aphid, Myzus persicae, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures t...

  15. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Cerataphis brasiliensis

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the palm aphid, Cerataphis brasiliensis, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures...

  16. Dynamic Quality Control for Transform Domain Wyner-Ziv Video Coding

    Directory of Open Access Journals (Sweden)

    Pereira Fernando

    2009-01-01

    Full Text Available Wyner-Ziv is an emerging video coding paradigm based on the Slepian-Wolf and Wyner-Ziv theorems where video coding may be performed by exploiting the temporal correlation at the decoder and not anymore at the encoder as in conventional video coding. This approach should allow designing low-complexity encoders, targeting important emerging applications such as wireless surveillance and visual sensor networks, without any cost in terms of RD performance. However, the currently available WZ video codecs do not allow controlling the target quality in an efficient way which is a major limitation for some applications. In this context, the main objective of this paper is to propose an efficient quality control algorithm to maintain a uniform quality along time in low-encoding complexity WZ video coding by dynamically adapting the quantization parameters depending on the desired target quality without any a priori knowledge about the sequence characteristics. This objective will be reached in the context of the so-called Stanford WZ video codec architecture which is currently the most used in the literature.

  17. Subjective Video Quality Assessment of H.265 Compression Standard for Full HD Resolution

    Directory of Open Access Journals (Sweden)

    Miroslav Uhrina

    2015-01-01

    Full Text Available Recently increasing interest in multimedia services leads to requirements for quality assessment, especially in the video domain. There are many factors that influence the video quality. Compression technology and transmission link imperfection can be considered as the main ones. This paper deals with the assessment of the impact of H.265/HEVC compression standard on the video quality using subjective metrics. The evaluation is done for two types of sequences with Full HD resolution depending on content. The paper is divided as follows. In the first part of the article, a short characteristic of the H.265/HEVC compression standard is written. In the second part, the subjective video quality methods used in our experiments are described. The last part of this article deals with the measurements and experimental results. They showed that quality of sequences coded between 5 and 7 Mbps is for observers sufficient, so there is no need for providers to use higher bitrates in streaming than this threshold. These results are part of a new model that is still being created and will be used for predicting the video quality in networks based on IP.

  18. Quality assurance in diagnostic radiology - assessing the fluoroscopic image quality

    International Nuclear Information System (INIS)

    Tabakov, S.

    1995-01-01

    The X-ray fluoroscopic image has a considerably lower resolution than the radiographic one. This requires a careful quality control aiming at optimal use of the fluoroscopic equipment. The basic procedures for image quality assessment of Image Intensifier/TV image are described. Test objects from Leeds University (UK) are used as prototypes. The results from examining 50 various fluoroscopic devices are shown. Their limiting spatial resolution varies between 0.8 lp/mm (at maximum II field size) and 2.24 lp/mm (at minimum field size). The mean value of the limiting spatial resolution for a 23 cm Image Intensifier is about 1.24 lp/mm. The mean limits of variation of the contrast/detail diagram for various fluoroscopic equipment are graphically expressed. 14 refs., 1 fig. (author)

  19. Quality Control in Diagnostic Radiology: Experiences and Achievements

    International Nuclear Information System (INIS)

    Mohd Khalid Matori; Husaini Salleh; Muhammad Jamal Md Isa

    2015-01-01

    Malaysian Nuclear Agency through its Medical Physics Group has been providing Quality Control (QC) services for medical X-ray apparatus used in diagnostic radiology to private clinics and hospitals since the year 1997. The Medical Physics Groups services is endorsed by the Malaysian Ministry Of Health (MOH) and is in accordance with the Malaysian Standard MS 838 and the Atomic Energy Licensing Act, 1984. Until today, the scopes of testing services also include all types of medical x-ray apparatus. The quality control (QC) in diagnostic radiology is considered as part of quality assurance program which provide accurate diagnostic information at the lowest cost and the least exposure of the patients to radiation. Many experience and obstacles were faced by Medical Physics Group. This paper will discuss the experiences and achievements of providing QC service from early stage until now so that it can be shared by the citizens of the Malaysian Nuclear Agency. The results of quality assurance inspection of all types of X-ray apparatus for medical conducted by Agency Nuclear Malaysia will be presented in brief. (author)

  20. Influence of Bit Depth on Subjective Video Quality Assessment for High Resolutions

    Directory of Open Access Journals (Sweden)

    Juraj Bienik

    2017-01-01

    Full Text Available This paper deals with the influence of bit depth on the subjective video quality assessment. To achieve this goal, eight video sequences, each representing a different content prototype, were analysed. Subjective evaluation was performed using the ACR method. The analysed video sequences were encoded to 8 and 10-bit bit depth. Two most used compression standards H.264 and H.265 were evaluated with 1, 3, 5, 10 and 15 Mbps bitrate in Full HD and UHD resolution. Finally, the perceived quality of both compression standards using the subjective tests with emphasis on bit-depth was compared. From the results we can state, that the practical application of 10-bit bit depth is not appropriate for Full HD resolution in the range of bitrate from 1 to 15 Mbps, for Ultra HD resolution, it is appropriate only for videos encoded by H.265/HEVC compression standard.

  1. Building a Reduced Reference Video Quality Metric with Very Low Overhead Using Multivariate Data Analysis

    Directory of Open Access Journals (Sweden)

    Tobias Oelbaum

    2008-10-01

    Full Text Available In this contribution a reduced reference video quality metric for AVC/H.264 is proposed that needs only a very low overhead (not more than two bytes per sequence. This reduced reference metric uses well established algorithms to measure objective features of the video such as 'blur' or 'blocking'. Those measurements are then combined into a single measurement for the overall video quality. The weights of the single features and the combination of those are determined using methods provided by multivariate data analysis. The proposed metric is verified using a data set of AVC/H.264 encoded videos and the corresponding results of a carefully designed and conducted subjective evaluation. Results show that the proposed reduced reference metric not only outperforms standard PSNR but also two well known full reference metrics.

  2. Intelligent Packet Shaper to Avoid Network Congestion for Improved Streaming Video Quality at Clients

    DEFF Research Database (Denmark)

    Kaul, Manohar; Khosla, Rajiv; Mitsukura, Y

    2003-01-01

    This paper proposes a traffic shaping algorithm based on neural networks, which adapts to a network over which streaming video is being transmitted. The purpose of this intelligent shaper is to eradicate all traffic congestion and improve the end-user's video quality. It possesses the capability...... of this intelligent traffic-shaping algorithm on the underlying network real time packet traffic and the eradication of unwanted abruption in the streaming video qualiy. This paper concluded from the end results of the simulation that neural networks are a very superior means of modeling real-time traffic...

  3. Investigating the quality of video consultations performed using fourth generation (4G) mobile telecommunications.

    Science.gov (United States)

    Caffery, Liam J; Smith, Anthony C

    2015-09-01

    The use of fourth-generation (4G) mobile telecommunications to provide real-time video consultations were investigated in this study with the aims of determining if 4G is a suitable telecommunications technology; and secondly, to identify if variation in perceived audio and video quality were due to underlying network performance. Three patient end-points that used 4G Internet connections were evaluated. Consulting clinicians recorded their perception of audio and video quality using the International Telecommunications Union scales during clinics with these patient end-points. These scores were used to calculate a mean opinion score (MOS). The network performance metrics were obtained for each session and the relationships between these metrics and the session's quality scores were tested. Clinicians scored the quality of 50 hours of video consultations, involving 36 clinic sessions. The MOS for audio was 4.1 ± 0.62 and the MOS for video was 4.4 ± 0.22. Image impairment and effort to listen were also rated favourably. There was no correlation between audio or video quality and the network metrics of packet loss or jitter. These findings suggest that 4G networks are an appropriate telecommunication technology to deliver real-time video consultations. Variations in quality scores observed during this study were not explained by the packet loss and jitter in the underlying network. Before establishing a telemedicine service, the performance of the 4G network should be assessed at the location of the proposed service. This is due to known variability in performance of 4G networks. © The Author(s) 2015.

  4. A model linking video gaming, sleep quality, sweet drinks consumption and obesity among children and youth.

    Science.gov (United States)

    Turel, O; Romashkin, A; Morrison, K M

    2017-08-01

    There is a growing need to curb paediatric obesity. The aim of this study is to untangle associations between video-game-use attributes and obesity as a first step towards identifying and examining possible interventions. Cross-sectional time-lagged cohort study was employed using parent-child surveys (t1) and objective physical activity and physiological measures (t2) from 125 children/adolescents (mean age = 13.06, 9-17-year-olds) who play video games, recruited from two clinics at a Canadian academic children's hospital. Structural equation modelling and analysis of covariance were employed for inference. The results of the study are as follows: (i) self-reported video-game play duration in the 4-h window before bedtime is related to greater abdominal adiposity (waist-to-height ratio) and this association may be mediated through reduced sleep quality (measured with the Pittsburgh Sleep Quality Index); and (ii) self-reported average video-game session duration is associated with greater abdominal adiposity and this association may be mediated through higher self-reported sweet drinks consumption while playing video games and reduced sleep quality. Video-game play duration in the 4-h window before bedtime, typical video-game session duration, sweet drinks consumption while playing video games and poor sleep quality have aversive associations with abdominal adiposity. Paediatricians and researchers should further explore how these factors can be altered through behavioural or pharmacological interventions as a means to reduce paediatric obesity. © 2017 World Obesity Federation.

  5. Modeling the Color Image and Video Quality on Liquid Crystal Displays with Backlight Dimming

    DEFF Research Database (Denmark)

    Korhonen, Jari; Mantel, Claire; Burini, Nino

    2013-01-01

    Objective image and video quality metrics focus mostly on the digital representation of the signal. However, the display characteristics are also essential for the overall Quality of Experience (QoE). In this paper, we use a model of a backlight dimming system for Liquid Crystal Display (LCD...

  6. Impairment-Factor-Based Audiovisual Quality Model for IPTV: Influence of Video Resolution, Degradation Type, and Content Type

    Directory of Open Access Journals (Sweden)

    Garcia MN

    2011-01-01

    Full Text Available This paper presents an audiovisual quality model for IPTV services. The model estimates the audiovisual quality of standard and high definition video as perceived by the user. The model is developed for applications such as network planning and packet-layer quality monitoring. It mainly covers audio and video compression artifacts and impairments due to packet loss. The quality tests conducted for model development demonstrate a mutual influence of the perceived audio and video quality, and the predominance of the video quality for the overall audiovisual quality. The balance between audio quality and video quality, however, depends on the content, the video format, and the audio degradation type. The proposed model is based on impairment factors which quantify the quality-impact of the different degradations. The impairment factors are computed from parameters extracted from the bitstream or packet headers. For high definition video, the model predictions show a correlation with unknown subjective ratings of 95%. For comparison, we have developed a more classical audiovisual quality model which is based on the audio and video qualities and their interaction. Both quality- and impairment-factor-based models are further refined by taking the content-type into account. At last, the different model variants are compared with modeling approaches described in the literature.

  7. Encryption for confidentiality of the network and influence of this to the quality of streaming video through network

    Science.gov (United States)

    Sevcik, L.; Uhrin, D.; Frnda, J.; Voznak, M.; Toral-Cruz, Homer; Mikulec, M.; Jakovlev, Sergej

    2015-05-01

    Nowadays, the interest in real-time services, like audio and video, is growing. These services are mostly transmitted over packet networks, which are based on IP protocol. It leads to analyses of these services and their behavior in such networks which are becoming more frequent. Video has become the significant part of all data traffic sent via IP networks. In general, a video service is one-way service (except e.g. video calls) and network delay is not such an important factor as in a voice service. Dominant network factors that influence the final video quality are especially packet loss, delay variation and the capacity of the transmission links. Analysis of video quality concentrates on the resistance of video codecs to packet loss in the network, which causes artefacts in the video. IPsec provides confidentiality in terms of safety, integrity and non-repudiation (using HMAC-SHA1 and 3DES encryption for confidentiality and AES in CBC mode) with an authentication header and ESP (Encapsulating Security Payload). The paper brings a detailed view of the performance of video streaming over an IP-based network. We compared quality of video with packet loss and encryption as well. The measured results demonstrated the relation between the video codec type and bitrate to the final video quality.

  8. Recurrent and Dynamic Models for Predicting Streaming Video Quality of Experience.

    Science.gov (United States)

    Bampis, Christos G; Li, Zhi; Katsavounidis, Ioannis; Bovik, Alan C

    2018-07-01

    Streaming video services represent a very large fraction of global bandwidth consumption. Due to the exploding demands of mobile video streaming services, coupled with limited bandwidth availability, video streams are often transmitted through unreliable, low-bandwidth networks. This unavoidably leads to two types of major streaming-related impairments: compression artifacts and/or rebuffering events. In streaming video applications, the end-user is a human observer; hence being able to predict the subjective Quality of Experience (QoE) associated with streamed videos could lead to the creation of perceptually optimized resource allocation strategies driving higher quality video streaming services. We propose a variety of recurrent dynamic neural networks that conduct continuous-time subjective QoE prediction. By formulating the problem as one of time-series forecasting, we train a variety of recurrent neural networks and non-linear autoregressive models to predict QoE using several recently developed subjective QoE databases. These models combine multiple, diverse neural network inputs, such as predicted video quality scores, rebuffering measurements, and data related to memory and its effects on human behavioral responses, using them to predict QoE on video streams impaired by both compression artifacts and rebuffering events. Instead of finding a single time-series prediction model, we propose and evaluate ways of aggregating different models into a forecasting ensemble that delivers improved results with reduced forecasting variance. We also deploy appropriate new evaluation metrics for comparing time-series predictions in streaming applications. Our experimental results demonstrate improved prediction performance that approaches human performance. An implementation of this work can be found at https://github.com/christosbampis/NARX_QoE_release.

  9. VQone MATLAB toolbox: A graphical experiment builder for image and video quality evaluations: VQone MATLAB toolbox.

    Science.gov (United States)

    Nuutinen, Mikko; Virtanen, Toni; Rummukainen, Olli; Häkkinen, Jukka

    2016-03-01

    This article presents VQone, a graphical experiment builder, written as a MATLAB toolbox, developed for image and video quality ratings. VQone contains the main elements needed for the subjective image and video quality rating process. This includes building and conducting experiments and data analysis. All functions can be controlled through graphical user interfaces. The experiment builder includes many standardized image and video quality rating methods. Moreover, it enables the creation of new methods or modified versions from standard methods. VQone is distributed free of charge under the terms of the GNU general public license and allows code modifications to be made so that the program's functions can be adjusted according to a user's requirements. VQone is available for download from the project page (http://www.helsinki.fi/psychology/groups/visualcognition/).

  10. Subjective quality of video sequences rendered on LCD with local backlight dimming at different lighting conditions

    DEFF Research Database (Denmark)

    Mantel, Claire; Korhonen, Jari; Pedersen, Jesper Mørkhøj

    2015-01-01

    light level (5 lux) and higher light level (60 lux) was organized to collect subjective data. Results show that participants prefer the method exploiting local dimming possibilities to the conventional full backlight but that this preference varies depending on the ambient light level. The clear......This paper focuses on the influence of ambient light on the perceived quality of videos displayed on Liquid Crystal Display (LCD) with local backlight dimming. A subjective test assessing the quality of videos with two backlight dimming methods and three lighting conditions, i.e. no light, low...

  11. Evaluation of the calibration of instruments in diagnostic radiology qualities

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Rodrigo N. de; Vivolo, Vitor; Potiens, Maria da Penha A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: rnfreitas@ipen.br; mppalbu@ipen.br

    2007-07-01

    T his work presents the analyze of the results obtained in the calibration of instruments used in mammography, computed tomography, dental and conventional diagnostic radiology dosimetry, using diagnostic radiology qualities as recommended by the standard IEC 61267 and ISO 4037-1. The instruments normally used for diagnostic radiology measurements are ionization chambers with volumes varying from 3 to 1800 cm{sup 3}, and can be cylindrical, spherical or plane parallel plates kind. They usually are sensitive to photon particles, with energies greater than 15 keV and can be used up to 1200 keV. In this work they were tested in X radiation fields from 25 to 150 kV, in specific qualities depending on the utilization of the instrument. The calibration results of 244 instruments received from 2005 to 2006 were analysed. About 20 instruments were not able to be calibrated due to bad functioning. The calibration coefficients obtained were between 0.88 and 1.24. (author)

  12. Is it safe to perform completion lobectomy after diagnostic wedge resection using video-assisted thoracoscopic surgery?

    DEFF Research Database (Denmark)

    Holbek, Bo Laksáfoss; Petersen, René Horsleben; Hansen, Henrik Jessen

    2016-01-01

    OBJECTIVES: The objective of this study was to assess the safety of video-assisted thoracoscopic surgery (VATS) completion lobectomy (CL) for non-small cell lung cancer (NSCLC) after diagnostic wedge resection by comparing with standard VATS lobectomy (SL). METHODS: Data were retrieved from...... test. RESULTS: In total 80 CL and 958 SLs were performed. There were no significant differences in median operating time, median chest drain duration or median length of stay. Median operative bleeding was 100 mL (IQR 50-238) in the CL group compared to 75 mL (IQR 25-200) in the SL group (p = 0.......99). CONCLUSIONS: This study comparing short-term surgical outcome and complications after surgical treatment of NSCLC indicates that VATS completion lobectomy after diagnostic wedge resection seems safe when looking at a relatively short time interval between the two procedures....

  13. Online Curves: A Quality Analysis of Scoliosis Videos on YouTube.

    Science.gov (United States)

    Staunton, Peter F; Baker, Joseph F; Green, James; Devitt, Aiden

    2015-12-01

    A cross-sectional study. The aim of this study was to evaluate the quality of online scoliosis information available on the video sharing site YouTube. The Internet is an increasingly utilized resource for accessing information about a variety of heath conditions. YouTube is a video sharing platform used to both seek and distribute information. A search for "scoliosis" was carried out using YouTube's search engine and data were collected on the first 50 videos returned. A JAMA score to determine currency, authorship, source and disclosure, and scoliosis-specific score that measures the amount of information on the diagnosis and treatment options (as devised by Mathur et al in 2005; scored 0-32) was recorded for each video to measure quality objectively. In addition, the number of views, number of comments, and feedback positivity was documented for each. Data analysis was conducted using R 3.1.4/R Studio 0.98 with control for the age of each video in analysis models. The average number of views per video was 71,152 with an average length of 7 minutes 32  seconds. Thirty-six percent of the videos fell under the authorship category of personal experience. The average JAMA score was 1.32/4 and average scoliosis specific score was 5.38/32. There was a positive correlation between JAMA score and number of views (P = 0.003). However, in contrast, there was a negative correlation between scoliosis-specific score and number of views (P = 0.01). Online health information has historically been poor and our study shows that in an environment like YouTube that lacks a peer review process, the quality of scoliosis information is low. Further work is needed to determine whether accessing information on YouTube can play a role in patient care other than simple education pertaining to the disease and its management. 3.

  14. Management of speech and video telephony quality in heterogeneous wireless networks

    CERN Document Server

    Lewcio, Błażej

    2014-01-01

    This book shows how networking research and quality engineering can be combined to successfully manage the transmission quality when speech and video telephony is delivered in heterogeneous wireless networks. Nomadic use of services requires intelligent management of ongoing transmission, and to make the best of available resources many fundamental trade-offs must be considered. Network coverage versus throughput and reliability of a connection is one key aspect, efficiency versus robustness of signal compression is another. However, to successfully manage services, user-perceived Quality of Experience (QoE) in heterogeneous networks must be known, and the perception of quality changes must be understood.  These issues are addressed in this book, in particular focusing on the perception of quality changes due to switching between diverse networks, speech and video codecs, and encoding bit rates during active calls.

  15. Quality Variation Control for Three-Dimensional Wavelet-Based Video Coders

    Directory of Open Access Journals (Sweden)

    Vidhya Seran

    2007-02-01

    Full Text Available The fluctuation of quality in time is a problem that exists in motion-compensated-temporal-filtering (MCTF- based video coding. The goal of this paper is to design a solution for overcoming the distortion fluctuation challenges faced by wavelet-based video coders. We propose a new technique for determining the number of bits to be allocated to each temporal subband in order to minimize the fluctuation in the quality of the reconstructed video. Also, the wavelet filter properties are explored to design suitable scaling coefficients with the objective of smoothening the temporal PSNR. The biorthogonal 5/3 wavelet filter is considered in this paper and experimental results are presented for 2D+t and t+2D MCTF wavelet coders.

  16. Quality Variation Control for Three-Dimensional Wavelet-Based Video Coders

    Directory of Open Access Journals (Sweden)

    Seran Vidhya

    2007-01-01

    Full Text Available The fluctuation of quality in time is a problem that exists in motion-compensated-temporal-filtering (MCTF- based video coding. The goal of this paper is to design a solution for overcoming the distortion fluctuation challenges faced by wavelet-based video coders. We propose a new technique for determining the number of bits to be allocated to each temporal subband in order to minimize the fluctuation in the quality of the reconstructed video. Also, the wavelet filter properties are explored to design suitable scaling coefficients with the objective of smoothening the temporal PSNR. The biorthogonal 5/3 wavelet filter is considered in this paper and experimental results are presented for 2D+t and t+2D MCTF wavelet coders.

  17. On subjective quality assessment of adaptive video streaming via crowdsourcing and laboratory based experiments

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Shahid, Muhammad; Pokhrel, Jeevan

    2017-01-01

    is therefore instrumental in improving this understanding. Controlled laboratory based perceptual quality experiments that involve a panel of human viewers are considered to be the most valid method of the assessment of QoE. Besides laboratory based subjective experiments, crowdsourcing based subjective...... assessment of video quality is gaining popularity as an alternative method. This article presents insights into a study that investigates perceptual preferences of various adaptive video streaming scenarios through crowdsourcing based and laboratory based subjective assessment. The major novel contribution...... of this study is the application of Paired Comparison based subjective assessment in a crowdsourcing environment. The obtained results provide some novel indications, besides confirming the earlier published trends, of perceptual preferences for adaptive scenarios of video streaming. Our study suggests...

  18. Quality control procedures of dental diagnostic radiology systems

    International Nuclear Information System (INIS)

    Andrade, Paula Serra Sasaki

    2007-01-01

    This work presents quality control reference procedures for dental diagnostic radiology systems, following the recommendations of the Publication 453 of the Brazilian Health Ministry (PF453), to be applied in dental clinics, in order to achieve an improvement in the radiological image qualities and the patient dose reduction. All tests were applied in an intraoral X rays system, following the methodology developed and the requirements of the PF 453. In order to verify the best quality of the image in relation to the smaller exposition time an object test was also developed in this work. The use of this object allowed the reduction of the exposition time of 0.5 seconds, the maximum value of the linear region of the characteristic curve, for 0.2 seconds. The tested X rays system showed a very good agreement with the applied procedures, detaching the reduction of the skin entrance dose using the film-holding devices. However, the size of the field increased and exceeded the maximum value of 6 cm recommended in the standard. The importance of the quality control in dental diagnostic radiology systems is essential due to the constant use of X radiation in dental clinics. The PF453 recommends the frequency of at least two years for the constancy tests. However, it is suggested that the professional, surgeon-dentist, should be responsible for the internal control of the image quality obtained from the X rays device. This can be done through monthly exposures of the object test developed in this work. (author)

  19. National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - overview

    Science.gov (United States)

    Training is a critical part of aphid (Hemiptera: Aphididae) identification. This training video provides provides an overview of general aphid morphology by using a compound microscope. The narrator discusses and highlights structures on the aphid that are important to make a species identification....

  20. A reference guide to quality assurance for diagnostic radiography

    International Nuclear Information System (INIS)

    1986-01-01

    The College of Radiographers, through its Professional and Technical Committee, set up a small Working Party to compile a list of references which would help radiographers to become experts at Quality Assurance in Diagnostic Imaging departments. The list is not comprehensive, but includes references which the Working Party have experience of and have found useful. The references provided should aid in the objectives of:- 1. determining acceptable standards of new equipment; 2. making comparisons during use with accepted base line performance; 3. establishing loss of cost effectiveness and the need for replacement. (author)

  1. Quality criteria in diagnostic radiology of the skull

    International Nuclear Information System (INIS)

    Friedmann, G.

    1985-01-01

    Diagnostic survey radiology of the skull relies on pictures to be taken if indicated and to meet all conceivable requirements. Those radiograph directions and projections were selected out of the profusion of known and described ones which allow both as small a number of pictures and as comprehensive a demonstration of all skull sections and1structures as possible. With this in mind, quality criteria for plain radiographs of the skull taken laterally and sagittably, for partial radiographs of the visceral cranium including orbit and of the base of the skull including petrons bone are described. (orig./MG) [de

  2. Investigating subjective attributes of quality for videos displayed with local backlight dimming

    DEFF Research Database (Denmark)

    Mantel, Claire; Bech, Søren; Forchhammer, Søren

    2014-01-01

    This paper investigates what composes the quality of videos displayed on LCD with local backlight dimming. In a sub- jective experiment, participants assessed the level of nine attributes defined using the Qualitative Descriptive Anal- ysis method. Results show that three attributes (Contrast...

  3. Sleep quality is negatively related to video gaming volume in adults.

    Science.gov (United States)

    Exelmans, Liese; Van den Bulck, Jan

    2015-04-01

    Most literature on the relationship between video gaming and sleep disturbances has looked at children and adolescents. There is little research on such a relationship in adult samples. The aim of the current study was to investigate the association of video game volume with sleep quality in adults via face-to-face interviews using standardized questionnaires. Adults (n = 844, 56.2% women), aged 18-94 years old, participated in the study. Sleep quality was measured using the Pittsburgh Sleep Quality Index, and gaming volume was assessed by asking the hours of gaming on a regular weekday (Mon-Thurs), Friday and weekend day (Sat-Sun). Adjusting for gender, age, educational level, exercise and perceived stress, results of hierarchical regression analyses indicated that video gaming volume was a significant predictor of sleep quality (β = 0.145), fatigue (β = 0.109), insomnia (β = 0.120), bedtime (β = 0.100) and rise time (β = 0.168). Each additional hour of video gaming per day delayed bedtime by 6.9 min (95% confidence interval 2.0-11.9 min) and rise time by 13.8 min (95% confidence interval 7.8-19.7 min). Attributable risk for having poor sleep quality (Pittsburgh Sleep Quality Index > 5) due to gaming >1 h day was 30%. When examining the components of the Pittsburgh Sleep Quality Index using multinomial regression analysis (odds ratios with 95% confidence intervals), gaming volume significantly predicted sleep latency, sleep efficiency and use of sleep medication. In general, findings support the conclusion that gaming volume is negatively related to the overall sleep quality of adults, which might be due to underlying mechanisms of screen exposure and arousal. © 2014 European Sleep Research Society.

  4. Quality control for diagnostic oral microbiology laboratories in European countries

    Directory of Open Access Journals (Sweden)

    Andrew J. Smith

    2011-11-01

    Full Text Available Participation in diagnostic microbiology internal and external quality control (QC processes is good laboratory practice and an essential component of a quality management system. However, no QC scheme for diagnostic oral microbiology existed until 2009 when the Clinical Oral Microbiology (COMB Network was created. At the European Oral Microbiology Workshop in 2008, 12 laboratories processing clinical oral microbiological samples were identified. All these were recruited to participate into the study and six laboratories from six European countries completed both the online survey and the first QC round. Three additional laboratories participated in the second round. Based on the survey, European oral microbiology laboratories process a significant (mean per laboratory 4,135 number of diagnostic samples from the oral cavity annually. A majority of the laboratories did not participate in any internal or external QC programme and nearly half of the laboratories did not have standard operating procedures for the tests they performed. In both QC rounds, there was a large variation in the results, interpretation and reporting of antibiotic susceptibility testing among the laboratories. In conclusion, the results of this study demonstrate the need for harmonisation of laboratory processing methods and interpretation of results for oral microbiology specimens. The QC rounds highlighted the value of external QC in evaluating the efficacy and safety of processes, materials and methods used in the laboratory. The use of standardised methods is also a prerequisite for multi-centre epidemiological studies that can provide important information on emerging microbes and trends in anti-microbial susceptibility for empirical prescribing in oro-facial infections.

  5. Modeling the Subjective Quality of Highly Contrasted Videos Displayed on LCD With Local Backlight Dimming

    DEFF Research Database (Denmark)

    Mantel, Claire; Bech, Søren; Korhonen, Jari

    2015-01-01

    Local backlight dimming is a technology aiming at both saving energy and improving visual quality on television sets. As the rendition of the image is specified locally, the numerical signal corresponding to the displayed image needs to be computed through a model of the display. This simulated...... signal can then be used as input to objective quality metrics. The focus of this paper is on determining which characteristics of locally backlit displays influence quality assessment. A subjective experiment assessing the quality of highly contrasted videos displayed with various local backlight...

  6. ATM Quality of Service Tests for Digitized Video Using ATM Over Satellite: Laboratory Tests

    Science.gov (United States)

    Ivancic, William D.; Brooks, David E.; Frantz, Brian D.

    1997-01-01

    A digitized video application was used to help determine minimum quality of service parameters for asynchronous transfer mode (ATM) over satellite. For these tests, binomially distributed and other errors were digitally inserted in an intermediate frequency link via a satellite modem and a commercial gaussian noise generator. In this paper, the relation- ship between the ATM cell error and cell loss parameter specifications is discussed with regard to this application. In addition, the video-encoding algorithms, test configurations, and results are presented in detail.

  7. Educational Quality of YouTube Videos in Thumb Exercises for Carpometacarpal Osteoarthritis: A Search on Current Practice.

    Science.gov (United States)

    Villafañe, Jorge Hugo; Cantero-Tellez, Raquel; Valdes, Kristin; Usuelli, Federico Giuseppe; Berjano, Pedro

    2017-09-01

    Conservative treatments are commonly performed therapeutic interventions for the management of carpometacarpal (CMC) joint osteoarthritis (OA). Physical and occupational therapies are starting to use video-based online content as both a patient teaching tool and a source for treatment techniques. YouTube is a popular video-sharing website that can be accessed easily. The purpose of this study was to analyze the quality of content and potential sources of bias in videos available on YouTube pertaining to thumb exercises for CMC OA. The YouTube video database was systematically searched using the search term thumb osteoarthritis and exercises from its inception to March 10, 2017. Authors independently selected videos, conducted quality assessment, and extracted results. A total of 832 videos were found using the keywords. Of these, 10 videos clearly demonstrated therapeutic exercise for the management of CMC OA. In addition, the top-ranked video found by performing a search of "views" was a video with more than 121 863 views uploaded in 2015 that lasted 12.33 minutes and scored only 2 points on the Global Score for Educational Value rating scale. Most of the videos viewed that described conservative interventions for CMC OA management have a low level of evidence to support their use. Although patients and novice hand therapists are using YouTube and other online resources, videos that are produced by expert hand therapists are scarce.

  8. Quality of life evaluation of workers for diagnostic radiology services

    International Nuclear Information System (INIS)

    Fernandes, Ivani Martins

    2011-01-01

    The main objective of this study was to evaluate the quality of life (QOL) of diagnostic radiology services workers at a hospital of Sao Paulo city. It aimed also to draw the profile of these workers identifying the variables, as its influence on their quality of life. A descriptive exploratory study with qualitative and quantitative approaches was carried out. The data were collected using the questionnaires: the abbreviated instrument for the assessment of the QOL, World Health Organization Quality of Life Instrument bref (WHOQOL-bref) and a questionnaire including the social demographic variables, work conditions and the variables that express the lifestyle of individuals, both questionnaires self-applied. The sample was formed by 118 workers, among them: physicians, technologists/technicians in radiology, nurses, technicians and assistants in nursing, and others health professionals. The data analysis included descriptive statistics, nonparametric tests and the use of a linear regression model. The reliability of the instrument for the studied sample was verified by Cronbach's Alpha Coefficient (α). The WHOQOL-bref proved to be an adequate instrument, with a good level of internal consistency (α=0.884), being easily and quickly administrated for the evaluation of the QOL. The study provided an overview of the perception of quality of life of the studied group. (author)

  9. Diagnostic image quality of mammograms in German outpatient medical care

    International Nuclear Information System (INIS)

    Pfandzelter, R.; Wuelfing, U.; Boedeker, B.

    2010-01-01

    Purpose: A total of 79 115 mammograms from statutory health insurance (SHI) physicians within German outpatient care were evaluated with respect to the diagnostic image quality. Materials and Methods: Mammograms were randomly selected between 2006 and 2008 by the regional Associations of Statutory Health Insurance Physicians and submitted to regional boards of experts for external evaluation. The mammogram quality was evaluated using a 3-point scale (adequate, borderline, failure) and documented using a nationally standardized protocol. Results: 87.6 % of the mammograms were classified as adequate, 11.0 % as borderline and 1.4 % as failure. Mediolateral oblique mammograms (mlo) had worse ratings than craniocaudal mammograms (cc). Main reasons for classifying the mammograms as borderline or failure were 'inframammary fold not adequately visualized' (mlo), 'pectoral muscle not in the correct angle or not to the level with the nipple' (mlo), 'the nipple not in profile' (mlo, cc) and 'breast not completely or not adequately visualized' (cc). Conclusion: The results show a good overall quality of mammograms in German outpatient medical care. Failures can be associated predominantly with incorrect positioning of the breast. More precisely defined quality criteria using objective measures are recommended, especially for craniocaudal mammograms (cc). (orig.)

  10. Using Supplementary Video in Multimedia Instruction as a Teaching Tool to Increase Efficiency of Learning and Quality of Experience

    Directory of Open Access Journals (Sweden)

    Milos Ljubojevic

    2014-07-01

    Full Text Available The main objective of this research is to investigate efficiency of use of supplementary video content in multimedia teaching. Integrating video clips in multimedia lecture presentations may increase students’ perception of important information and motivation for learning. Because of that, students can better understand and remember key points of a lecture. Those improvements represent some important learning outcomes. This research showed that segmentation of teaching materials with supplementary video clips may improve lecture organization and presentation in order to achieve effective teaching and learning. The context of the video content and the position of supplementary video clips in teaching material are important influences on factors for motivation and efficiency of learning. This research presents the effects of the use of supplementary videos with different context of content (entertainment and educational as well as the effects of their position within the teaching material. The experimental results showed that the most efficient method of use of supplementary video is integration with educational video content in the middle of a lecture. This position of video insertion provides the best results. The context of video content influences efficiency of learning also. Entertainment video was not as efficient as educational, but it can be used to engage and motivate students for learning. The given results have been confirmed with a subjective assessment of students’ quality of experience with different methods of embedding video clips.

  11. Quality of dementia diagnostic evaluation for ethnic minority patients: a nationwide study

    DEFF Research Database (Denmark)

    Nielsen, T Rune; Andersen, Birgitte Bo; Kastrup, Marianne

    2011-01-01

    Background/Aims: Diagnostic evaluation of dementia for ethnic minority patients may be challenging. This study aimed to evaluate the quality of diagnostic evaluation of dementia for patients from ethnic minorities in Denmark. Methods: The Danish national hospital registers were used to identify p......: There are significant ethnic disparities in the quality of diagnostic evaluations and outcome of dementia in the secondary healthcare sector....

  12. Impact of GoP on the Video Quality of VP9 Compression Standard for Full HD Resolution

    Directory of Open Access Journals (Sweden)

    Miroslav Uhrina

    2016-01-01

    Full Text Available In the last years, the interest on multimedia services has significantly increased. This leads to requirements for quality assessment, especially in video domain. Compression together with the transmission link imperfection are two main factors that influence the quality. This paper deals with the assessment of the Group of Pictures (GoP impact on the video quality of VP9 compression standard. The evaluation was done using selected objective and subjective methods for two types of Full HD sequences depending on content. These results are part of a new model that is still being created and will be used for predicting the video quality in networks based on IP.

  13. A novel no-reference objective stereoscopic video quality assessment method based on visual saliency analysis

    Science.gov (United States)

    Yang, Xinyan; Zhao, Wei; Ye, Long; Zhang, Qin

    2017-07-01

    This paper proposes a no-reference objective stereoscopic video quality assessment method with the motivation that making the effect of objective experiments close to that of subjective way. We believe that the image regions with different visual salient degree should not have the same weights when designing an assessment metric. Therefore, we firstly use GBVS algorithm to each frame pairs and separate both the left and right viewing images into the regions with strong, general and week saliency. Besides, local feature information like blockiness, zero-crossing and depth are extracted and combined with a mathematical model to calculate a quality assessment score. Regions with different salient degree are assigned with different weights in the mathematical model. Experiment results demonstrate the superiority of our method compared with the existed state-of-the-art no-reference objective Stereoscopic video quality assessment methods.

  14. Effect of TV content in subjective assessment of video quality on mobile devices

    Science.gov (United States)

    Jumisko, Satu H.; Ilvonen, Ville P.; Vaananen-Vainio-Mattila, Kaisa A.

    2005-03-01

    Selection of test materials in subjective assessment methodology recommendations is based mainly on technical parameters. Materials should test the ability of the codec to cope with spatial and temporal redundancy. However consumers watch TV for a reason -- one of the main criteria is the interesting content. In this study we examined whether the content recognition and subjects" personal interests have an effect on quality assessment. We also studied subjective assessment criteria for video quality. The study was done using small resolution and low bit rate video in mobile phones in a laboratory environment. Altogether 135 subjects, aged 18-65 years, participated in the tests. The test started with a subjective assessment of video quality using well-known TV content. Afterwards a survey was done to measure content recognition and level of interests in the content. The test session ended up with a qualitative interview about evaluation criteria. Our studies showed that there is a connection between interest in content and given quality score with TV content. Therefore we raise a concern on content selection and recommend measuring the evaluator"s interest in content in subjective assessment studies. The study on subjective evaluation criteria revealed that subjects pay attention on content and quality impairments especially in regions of interest.

  15. Rocket engine plume diagnostics using video digitization and image processing - Analysis of start-up

    Science.gov (United States)

    Disimile, P. J.; Shoe, B.; Dhawan, A. P.

    1991-01-01

    Video digitization techniques have been developed to analyze the exhaust plume of the Space Shuttle Main Engine. Temporal averaging and a frame-by-frame analysis provide data used to evaluate the capabilities of image processing techniques for use as measurement tools. Capabilities include the determination of the necessary time requirement for the Mach disk to obtain a fully-developed state. Other results show the Mach disk tracks the nozzle for short time intervals, and that dominate frequencies exist for the nozzle and Mach disk movement.

  16. Quality assurance of computed tomography scanner beams in diagnostic radiology

    International Nuclear Information System (INIS)

    Lindskoug, B.A.

    1989-01-01

    The number of computed tomography (CT) scanners in diagnostic radiology is increasing, to the extent that they are now found in relatively small hospitals. These hospitals do not have local physicists available and so methods must be developed to allow quality assurance to be carried out at distant laboratories. Several different types of solid water phantoms are available with various built-in test objects that may supply sufficient information about the many parameters that must be checked. The dose distributions, however, are usually not so well considered, although the connection between image quality and absorbed dose must be known for optimal use of a CT scanner. By introducing thermoluminescent dosemeters (TLDs) into a commercial phantom (RMI), it was possible to measure the absorbed dose profile and the line integral of the absorbed dose across the slit. The computer-guided readout of the TLDs gives the absorbed dose, the average dose and half maximum width, absorbed dose curve, and also the line integral of the peak. The only modification of the phantom was five holes, drilled at strategic positions, that did not influence the built-in test objects. This single measurement provides an appropriate monthly quality assurance check of the CT scanner with little extra effort. (author)

  17. Postoperative myocardial infarction after diagnostic video-assisted thoracoscopy and pleurodesis for catamenial pneumothorax: A unique case report

    Directory of Open Access Journals (Sweden)

    G Madhavi

    2010-01-01

    Full Text Available Myocardial infarction (MI is uncommon in patients undergoing noncardiac surgery without a history of coronary artery disease. But, patients with compromised pulmonary function and coexisting anaemia superimposed by precipitating factors like prolonged hypotension and tachycardia can culminate in myocardial catastrophe even in the absence of risk factors. We are herewith reporting an unusual case of postoperative non-ST elevation MI without any pre-existing ischemic heart disease. A 39-year-old female patient who was submitted for diagnostic video-assisted thoracoscopy and chemical pleurodesis for recurrent pneumothorax developed postoperative MI. After review of all the factors, it was found that the patient developed Type 2 MI as a sequel to oxygen supply and demand mismatch secondary to hypoxia and prolonged hypotension. This was evident in the 12-lead electrocardiogram and was confirmed by elevated cardiac biomarkers and regional wall motion abnormality on echocardiography.

  18. Laboratory diagnostic methods, system of quality and validation

    Directory of Open Access Journals (Sweden)

    Ašanin Ružica

    2005-01-01

    Full Text Available It is known that laboratory investigations secure safe and reliable results that provide a final confirmation of the quality of work. Ideas, planning, knowledge, skills, experience, and environment, along with good laboratory practice, quality control and reliability of quality, make the area of biological investigations very complex. In recent years, quality control, including the control of work in the laboratory, is based on international standards and is used at that level. The implementation of widely recognized international standards, such as the International Standard ISO/IEC 17025 (1 and the implementing of the quality system series ISO/IEC 9000 (2 have become the imperative on the grounds of which laboratories have a formal, visible and corresponding system of quality. The diagnostic methods that are used must constantly yield results which identify the animal as positive or negative, and the precise status of the animal is determined with a predefined degree of statistical significance. Methods applied on a selected population reduce the risk of obtaining falsely positive or falsely negative results. A condition for this are well conceived and documented methods, with the application of the corresponding reagents, and work with professional and skilled staff. This process requires also a consistent implementation of the most rigorous experimental plans, epidemiological and statistical data and estimations, with constant monitoring of the validity of the applied methods. Such an approach is necessary in order to cut down the number of misconceptions and accidental mistakes, for a referent population of animals on which the validity of a method is tested. Once a valid method is included in daily routine investigations, it is necessary to apply constant monitoring for the purpose of internal quality control, in order adequately to evaluate its reproducibility and reliability. Consequently, it is necessary at least twice yearly to conduct

  19. Diagnostic Yield and Clinical Impact of Video Capsule Endoscopy in Patients with Chronic Diarrhea: A Korean Multicenter CAPENTRY Study.

    Science.gov (United States)

    Song, Hyun Joo; Moon, Jeong Seop; Jeon, Seong Ran; Kim, Jin-Oh; Kim, Jinsu; Cheung, Dae Young; Choi, Myung-Gyu; Lim, Yun Jeong; Shim, Ki-Nam; Ye, Byong Duk; Cheon, Jae Hee; Park, Cheol Hee; Kim, Hyun-Soo; Kim, Ji Hyun; Chang, Dong Kyung; Do, Jae Hyuk; Kim, Kyeong Ok; Jang, Byung Ik; Shin, Sung-Jae

    2017-03-15

    In some cases, chronic diarrhea is unexplained, and small bowel disorders may be one of the causes. The aim of this study was to assess the diagnostic yield and clinical impact of video capsule endoscopy (VCE) in patients with chronic diarrhea. We retrospectively analyzed records from October 2002 to August 2013 in the VCE nationwide database registry (n=2,964). Ninety-one patients from 15 medical centers (60 males and 31 females; mean age, 47±19 years) were evaluated for VCE as a result of chronic diarrhea. The duration of chronic diarrhea was 8.3±14.7 months. The positive diagnostic yield of VCE was 42.9% (39/91). However, 15.4% (14/91) exhibited an inconsistent result, and 41.8% (38/91) were negative. Abnormal findings consistent with chronic diarrhea included erosions/aphthous ulcers (19.8%), ulcers (17.6%), mucosal erythema (3.3%), edema (1.1%), and luminal narrowing (1.1%). The most common diagnoses were functional diarrhea associated with irritable bowel syndrome in 37 patients (40.7%) and Crohn's disease in 18 patients (19.8%). After VCE examination, the diagnosis was changed in 34.1% of the patients (31/91). Hematochezia (odds ratio [OR], 8.802; 95% confidence interval [CI], 2.126 to 36.441) and hypoalbuminemia (OR, 4.811; 95% CI, 1.241 to 18.655) are predictive factors of a positive diagnostic yield. VCE had a favorable diagnostic yield and clinical impact on the management of patients with chronic diarrhea.

  20. Sensor and Video Monitoring of Water Quality at Bristol Floating Harbour

    Science.gov (United States)

    Chen, Yiheng; Han, Dawei

    2017-04-01

    Water system is an essential component in a smart city for its sustainability and resilience. The harbourside is a focal area of​ ​Bristol with new buildings and features redeveloped in the last ten years, attracting numerous visitors by the diversity of attractions and beautiful views. There is a strong​ ​relationship between the satisfactory of the visitors and local people with the water quality in the Harbour. The freshness and beauty of the water body would please people as well as benefit the aquatic ecosystems. As we are entering a data-rich era, this pilot project aims to explore the concept of using​ ​ video cameras and smart sensors to collect and monitor water quality condition at the Bristol harbourside. The video cameras and smart sensors are connected to the Bristol Is Open network, an open programmable city platform. This will be the​ first​ attempt to collect water quality data in real time in the​ ​Bristol urban area with the wireless network. The videos and images of the water body collected by the cameras will be correlated with the in-situ water quality parameters for research​ ​purposes. The successful implementation of the sensors can attract more academic researchers and industrial partners to expand the sensor network to multiple locations​ ​around the city covering the other parts of the Harbour and River Avon, leading to a new generation of urban system infrastructure model.

  1. Quality of pharmaceutical care at the pharmacy counter: patients’ experiences versus video observation

    Directory of Open Access Journals (Sweden)

    Koster ES

    2016-03-01

    Full Text Available Ellen S Koster,1 Lyda Blom,1 Marloes R Overbeeke,1 Daphne Philbert,1 Marcia Vervloet,2 Laura Koopman,2,3 Liset van Dijk2 1Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht University, the Netherlands; 2Netherlands Institute of Health Services Research (NIVEL, Utrecht, the Netherlands; 3National Health Care Institute, Diemen, the Netherlands Introduction: Consumer Quality Index questionnaires are used to assess quality of care from patients’ experiences.Objective: To provide insight into the agreement about quality of pharmaceutical care, measured both by a patient questionnaire and video observations.Methods: Pharmaceutical encounters in four pharmacies were video-recorded. Patients completed a questionnaire based upon the Consumer Quality Index Pharmaceutical Care after the encounter containing questions about patients’ experiences regarding information provision, medication counseling, and pharmacy staff’s communication style. An observation protocol was used to code the recorded encounters. Agreement between video observation and patients’ experiences was calculated.Results: In total, 109 encounters were included for analysis. For the domains “medication counseling” and “communication style”, agreement between patients’ experiences and observations was very high (>90%. Less agreement (45% was found for “information provision”, which was rated more positive by patients compared to the observations, especially for the topic, encouragement of patients’ questioning behavior.Conclusion: A questionnaire is useful to assess the quality of medication counseling and pharmacy staff’s communication style, but might be less suitable to evaluate information provision and pharmacy staff’s encouragement of patients’ questioning behavior. Although patients may believe that they have received all necessary information to use their new medicine, some information on specific instructions was not addressed during

  2. Video laryngoscopy in pre-hospital critical care - a quality improvement study.

    Science.gov (United States)

    Rhode, Marianne Grønnebæk; Vandborg, Mads Partridge; Bladt, Vibeke; Rognås, Leif

    2016-06-13

    Pre-hospital endotracheal intubation is challenging and repeated endotracheal intubation is associated with increased morbidity and mortality. We investigated whether the introduction of the McGrath MAC video laryngoscope as the primary device for pre-hospital endotracheal intubation could improve first-pass success rate in our anaesthesiologist-staffed pre-hospital critical care services. We also investigated the incidence of failed pre-hospital endotracheal intubation, the use of airway adjuncts and back-up devices and problems encountered using the McGrath MAC video laryngoscope. Prospective quality improvement study collecting data from all adult pre-hospital endotracheal intubation performed by four anaesthesiologist-staffed pre-hospital critical care teams between December 15(th) 2013 and December 15(th) 2014. We registered data from 273 consecutive patients. When using the McGrath MAC video laryngoscope the overall pre-hospital endotracheal intubation first-pass success rate was 80.8 %. Following rapid sequence intubation (RSI) it was 88.9 %. This was not significantly different from previously reported first-pass success rates in our system (p = 0.27 and p = 0.41). During the last nine months of the study period the overall first-pass success rate was 80.1 (p = 0.47) but the post-RSI first-pass success rate improved to 94.4 % (0.048). The overall pre-hospital endotracheal intubation success rate with the McGrath MAC video laryngoscope was 98.9 % (p = 0.17). Gastric content, blood or secretion in the airway resulted in reduced vision when using the McGrath MAC video laryngoscope. In this study of video laryngoscope implementation in a Scandinavian anaesthesiologist-staffed pre-hospital critical care service, overall pre-hospital endotracheal first pass success rate did not change. The post-RSI first-pass success rate was significantly higher during the last nine months of our 12-month study compared with our results from before

  3. Quality of dementia diagnostic evaluation for ethnic minority patients: a nationwide study

    DEFF Research Database (Denmark)

    Nielsen, T Rune; Andersen, Birgitte Bo; Kastrup, Marianne

    2011-01-01

    Background/Aims: Diagnostic evaluation of dementia for ethnic minority patients may be challenging. This study aimed to evaluate the quality of diagnostic evaluation of dementia for patients from ethnic minorities in Denmark. Methods: The Danish national hospital registers were used to identify...... records were reviewed. An acceptable diagnostic workup was documented in only 23% of the patients. Dementia diagnosis was confirmed in 35%. Significant differences in the quality of the diagnostic evaluation were found between patients from ethnic minorities and the general population. Conclusion......: There are significant ethnic disparities in the quality of diagnostic evaluations and outcome of dementia in the secondary healthcare sector....

  4. Modeling the subjective quality of highly contrasted videos displayed on LCD with local backlight dimming.

    Science.gov (United States)

    Mantel, Claire; Bech, Søren; Korhonen, Jari; Forchhammer, Søren; Pedersen, Jesper Melgaard

    2015-02-01

    Local backlight dimming is a technology aiming at both saving energy and improving visual quality on television sets. As the rendition of the image is specified locally, the numerical signal corresponding to the displayed image needs to be computed through a model of the display. This simulated signal can then be used as input to objective quality metrics. The focus of this paper is on determining which characteristics of locally backlit displays influence quality assessment. A subjective experiment assessing the quality of highly contrasted videos displayed with various local backlight-dimming algorithms is set up. Subjective results are then compared with both objective measures and objective quality metrics using different display models. The first analysis indicates that the most significant objective features are temporal variations, power consumption (probably representing leakage), and a contrast measure. The second analysis shows that modeling of leakage is necessary for objective quality assessment of sequences displayed with local backlight dimming.

  5. Preparation of photo an video images during foot diagnostics in stress condition

    International Nuclear Information System (INIS)

    Katsarov, V; Stoyanov, K.; Panchev, P.; Belcheva, J.; Atanasov, A.

    2008-01-01

    The aim of this work is to present some practical issues concerning image scanning, processing and software application in orthopedics and traumatology for foot diagnostic purposes. Basic concepts in optical scanning, multi-position photography and technology with high informational value have been discussed. The use of Slide show, Clip and Mpeg graphic formats during preparation for capture and image processing has been also demonstrated

  6. A comparative study of quality control in diagnostic radiology

    International Nuclear Information System (INIS)

    Kharita, M. H.; Khedr, M.S.; Wannus, K.M.

    2008-01-01

    The main objective of this comparative study was to evaluate the national quality assurance program for X-ray diagnostic radiology in Syrian governmental hospitals. Two periods were covered in this study, the first period was from 1986 to 1998 (52 hospitals and 149 X-ray machines were considered) and the second period from 1999 to 2005 (41 hospitals and 95 X-ray machines were considered). Most of the X-ray machines studied were within the acceptable performance, but few machines needed recalibration for some parameters. Considerable improvement of about 50% was reported in the second period. This improvement could be attributed to the establishment of an effective National Regulatory Authority in Syria in 1998 that introduced and gradually enforced the quality assurance requirement for X-ray equipment as part of the licensing process and to the relatively newer X-ray machines covered in the second period. The Author 2008. Published by Oxford Univ. Press. All rights reserved. (authors)

  7. Diagnostic Air Quality Model Evaluation of Source-Specific ...

    Science.gov (United States)

    Ambient measurements of 78 source-specific tracers of primary and secondary carbonaceous fine particulate matter collected at four midwestern United States locations over a full year (March 2004–February 2005) provided an unprecedented opportunity to diagnostically evaluate the results of a numerical air quality model. Previous analyses of these measurements demonstrated excellent mass closure for the variety of contributing sources. In this study, a carbon-apportionment version of the Community Multiscale Air Quality (CMAQ) model was used to track primary organic and elemental carbon emissions from 15 independent sources such as mobile sources and biomass burning in addition to four precursor-specific classes of secondary organic aerosol (SOA) originating from isoprene, terpenes, aromatics, and sesquiterpenes. Conversion of the source-resolved model output into organic tracer concentrations yielded a total of 2416 data pairs for comparison with observations. While emission source contributions to the total model bias varied by season and measurement location, the largest absolute bias of −0.55 μgC/m3 was attributed to insufficient isoprene SOA in the summertime CMAQ simulation. Biomass combustion was responsible for the second largest summertime model bias (−0.46 μgC/m3 on average). Several instances of compensating errors were also evident; model underpredictions in some sectors were masked by overpredictions in others. The National Exposure Research L

  8. A quality measurement study of a diagnostic x-ray

    International Nuclear Information System (INIS)

    Nishitani, Motohiro; Fujimoto, Nobuhisa; Yamada, Katsuhiko

    1982-01-01

    It is important to check periodically the quality and quantity of the X-rays emitted, in order to obtain the best possible performance from your diagnostic X-ray apparatus. The best way of checking the exact quality of the X-ray is to measure the spectrum of the X-ray, but it is not an easy task to carry out. The second way is to plot the attenuation curve of the X-rays. We have developed a method to plot the attenuation curve by a single exposure, utilizing J.r. Greening's empirical formula. The output of the three cavity ionization chambers, one with 7 mmAl filter, another with a 3 mmAl and the third without any filter, exposed to the same X-ray, were put into a microcomputer. The programming was arranged to display the attenuation curve of the X-rays, effective energy of the X-rays, the 1st HVL and the 2nd HVL on the CRT. The attenuation curves of the X-rays, emitted at a tube voltage at between 60 and 140 kV obtained by this method, agreed with the experimental results with an error of +-4 %. The effective energy obtained by this method agreed with the experimental data with an error of +-1 %. (author)

  9. Quality optimization of H.264/AVC video transmission over noisy environments using a sparse regression framework

    Science.gov (United States)

    Pandremmenou, K.; Tziortziotis, N.; Paluri, S.; Zhang, W.; Blekas, K.; Kondi, L. P.; Kumar, S.

    2015-03-01

    We propose the use of the Least Absolute Shrinkage and Selection Operator (LASSO) regression method in order to predict the Cumulative Mean Squared Error (CMSE), incurred by the loss of individual slices in video transmission. We extract a number of quality-relevant features from the H.264/AVC video sequences, which are given as input to the LASSO. This method has the benefit of not only keeping a subset of the features that have the strongest effects towards video quality, but also produces accurate CMSE predictions. Particularly, we study the LASSO regression through two different architectures; the Global LASSO (G.LASSO) and Local LASSO (L.LASSO). In G.LASSO, a single regression model is trained for all slice types together, while in L.LASSO, motivated by the fact that the values for some features are closely dependent on the considered slice type, each slice type has its own regression model, in an e ort to improve LASSO's prediction capability. Based on the predicted CMSE values, we group the video slices into four priority classes. Additionally, we consider a video transmission scenario over a noisy channel, where Unequal Error Protection (UEP) is applied to all prioritized slices. The provided results demonstrate the efficiency of LASSO in estimating CMSE with high accuracy, using only a few features. les that typically contain high-entropy data, producing a footprint that is far less conspicuous than existing methods. The system uses a local web server to provide a le system, user interface and applications through an web architecture.

  10. Comparison of Inter-Observer Variability and Diagnostic Performance of the Fifth Edition of BI-RADS for Breast Ultrasound of Static versus Video Images.

    Science.gov (United States)

    Youk, Ji Hyun; Jung, Inkyung; Yoon, Jung Hyun; Kim, Sung Hun; Kim, You Me; Lee, Eun Hye; Jeong, Sun Hye; Kim, Min Jung

    2016-09-01

    Our aim was to compare the inter-observer variability and diagnostic performance of the Breast Imaging Reporting and Data System (BI-RADS) lexicon for breast ultrasound of static and video images. Ninety-nine breast masses visible on ultrasound examination from 95 women 19-81 y of age at five institutions were enrolled in this study. They were scheduled to undergo biopsy or surgery or had been stable for at least 2 y of ultrasound follow-up after benign biopsy results or typically benign findings. For each mass, representative long- and short-axis static ultrasound images were acquired; real-time long- and short-axis B-mode video images through the mass area were separately saved as cine clips. Each image was reviewed independently by five radiologists who were asked to classify ultrasound features according to the fifth edition of the BI-RADS lexicon. Inter-observer variability was assessed using kappa (κ) statistics. Diagnostic performance on static and video images was compared using the area under the receiver operating characteristic curve. No significant difference was found in κ values between static and video images for all descriptors, although κ values of video images were higher than those of static images for shape, orientation, margin and calcifications. After receiver operating characteristic curve analysis, the video images (0.83, range: 0.77-0.87) had higher areas under the curve than the static images (0.80, range: 0.75-0.83; p = 0.08). Inter-observer variability and diagnostic performance of video images was similar to that of static images on breast ultrasonography according to the new edition of BI-RADS. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  11. Impact of H.264/AVC and H.265/HEVC Compression Standards on the Video Quality for 4K Resolution

    Directory of Open Access Journals (Sweden)

    Miroslav Uhrina

    2014-01-01

    Full Text Available This article deals with the impact of H.264/AVC and H.265/HEVC compression standards on the video quality for 4K resolution. In the first part a short characteristic of both compression standards is written. The second part focuses on the well-known objective metrics which were used for evaluating the video quality. In the third part the measurements and the experimental results are described.

  12. Capturing and displaying microscopic images used in medical diagnostics and forensic science using 4K video resolution - an application in higher education.

    Science.gov (United States)

    Maier, Hans; de Heer, Gert; Ortac, Ajda; Kuijten, Jan

    2015-11-01

    To analyze, interpret and evaluate microscopic images, used in medical diagnostics and forensic science, video images for educational purposes were made with a very high resolution of 4096 × 2160 pixels (4K), which is four times as many pixels as High-Definition Video (1920 × 1080 pixels). The unprecedented high resolution makes it possible to see details that remain invisible to any other video format. The images of the specimens (blood cells, tissue sections, hair, fibre, etc.) are recorded using a 4K video camera which is attached to a light microscope. After processing, this resulted in very sharp and highly detailed images. This material was then used in education for classroom discussion. Spoken explanation by experts in the field of medical diagnostics and forensic science was also added to the high-resolution video images to make it suitable for self-study. © 2015 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.

  13. A Comparison of Face to Face and Video-Based Self Care Education on Quality of Life of Hemodialysis Patients.

    Science.gov (United States)

    Hemmati Maslakpak, Masumeh; Shams, Shadi

    2015-07-01

    End stage renal disease negatively affects the patients' quality of life. There are different educational methods to help these patients. This study was performed to compare the effectiveness of self-care education in two methods, face to face and video educational, on the quality of life in patients under treatment by hemodialysis in education-medical centers in Urmia. In this quasi-experimental study, 120 hemodialysis patients were selected randomly; they were then randomly allocated to three groups: the control, face to face education and video education. For face to face group, education was given individually in two sessions of 35 to 45 minutes. For video educational group, CD was shown. Kidney Disease Quality Of Life- Short Form (KDQOL-SF) questionnaire was filled out before and two months after the intervention. Data analysis was performed in SPSS software by using one-way ANOVA. ANOVA test showed a statistically significant difference in the quality of life scores among the three groups after the intervention (P=0.024). After the intervention, Tukey's post-hoc test showed a statistically significant difference between the two groups of video and face to face education regarding the quality of life (P>0.05). Implementation of the face to face and video education methods improves the quality of life in hemodialysis patients. So, it is suggested that video educational should be used along with face to face education.

  14. Video ambulatory EEG: A good alternative to inpatient video telemetry?

    Science.gov (United States)

    Kandler, Rosalind; Ponnusamy, Athi; Wragg, Claire

    2017-04-01

    Video ambulatory EEG (V-AEEG) is a new technique which could add increased capacity for long term EEG monitoring to overstretched inpatient video telemetry (IPVT) services. We compare V-AEEG and IPVT for diagnostic efficacy, recording quality, patient acceptability and technologist time required. Forty-one V-AEEG and 64 IPVT adult patients were included. Patients were investigated to diagnose attacks or to obtain polysomnography (PSG) prior to multiple sleep latency test (MSLT). Number of attacks recorded, whether the diagnostic question was answered, quality of video and EEG recording and patients' preference for investigation at home or in hospital were noted. For V-AEEG patients, ease of procedure and extra technologist time required were recorded. Of patients investigated for diagnosis of attacks, 74% V-AEEG patients and 62% IPVT had typical attacks during the investigation. All PSGs were useful in interpreting the MSLTs. Diagnostic questions were answered by 73% V-AEEGs and 73% IPVTs. Quality of EEG and video recording was similar using V-AEEG and IPVT. Four patients had difficulty using V-AEEG equipment but diagnostic information was lost in only one. 5% of V-AEEG patients would have preferred hospital investigation but 45% of IPVT patients would have preferred home investigation. Extra technologist time for home visits (mean 2h) was required only for the first 7 patients. Video EEG recording quality and diagnostic efficacy from V-AEEG are similar to IPVT. V-AEEG is acceptable to most patients and does not require additional technical time. Hence, V-AEEG offers a convenient, economical alternative to IPVT. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  15. Diagnostic quality of dual-source coronary CT exams performed without heart rate control: importance of obesity and heart rate on image quality

    Science.gov (United States)

    Zimmerman, Stefan L.; Kral, Brian G.; Fishman, Elliot K.

    2014-01-01

    Objectives For dual source cardiac CTs without heart rate control, the influence of body habitus on quality is uncertain. We evaluated study quality across a range of heart rates (HR) and body size. Methods 160 subjects were randomly selected for four HR groups [quality was scored on a 3 point scale (1=non-diagnostic, 2=diagnostic, 3=excellent). Results 99% of coronaries were diagnostic quality. Six vessels were non-diagnostic, mostly due to motion. Nondiagnostic or diagnostic scores (quality but 6% of vessels in overweight and 17% in obese subjects had diagnostic scores quality cardiac CT exams can be obtained without premedication regardless of body size. PMID:25032805

  16. Patient dosimetry and quality control in diagnostic radiology

    International Nuclear Information System (INIS)

    Suliman, I. I.

    2007-08-01

    In the first part of the study, entrance surface doses (ESDs) to patients in radiography were estimated from x-ray tube output parameters for a sample of 346 radiographs. The mean ESDs estimated in the hospitals ranged from 0.17 to 0.27 mGy for chest PA, 1.04-2.26 mGy for skull AP/PA, 0.83-1.32 mGy for skull LAT, 1.31-1.89 mGy for pelvis AP, 1.46-3.33 mGy for Lumbar Spine AP and 2.9-9.9 mGy for Lumbar Spine LAT. With the exception of chest PA examination at two hospitals, mean ESDs were found to be within the established international reference doses. In addition, study was performed to compare two methods used for effective dose calculation in diagnostic radiology. Initially, ED values were calculated from ESD values using NRPB-SR262 Monte Carlo data and XDOSE software. Next, the energy imparted to patients was computed using values for entrance skin exposure-area product and half-value layer. Effective doses were then determined from energy imparted using ED/ε conversion factors proposed in the literature. Mean ED values calculated using the two methods were: 21.3-23.4, 14.1-12.8, 7.9-8.5, 232-226, 215-223 and 91-85.6 μSv for chest PA, Skull AP/PA, Skull LAT, Pelvis AP, Lumbar Spine AP and Lumbar Spine LAT examinations, respectively. The values obtained were in agreement between themselves and with data reported in the literature. In the second part, a protocol for quality control (QC) tests has been drafted based on various national and international recommendations. Tests were included for various parts of the imaging chain, i.e. x-ray tube and generator; x-ray tube control system; laser printer and display station; image quality and patient dose. Preliminary tolerance levels have been set for the various tests, after initial measurements. To check the suitability of the QC tests and the stated tolerance levels, measurements were made at the University Hospital Gasthuisberg in Leuven, the Netherland, for equipment used for paediatric radiology and a unit used

  17. A blinded assessment of video quality in wearable technology for telementoring in open surgery: the Google Glass experience.

    Science.gov (United States)

    Hashimoto, Daniel A; Phitayakorn, Roy; Fernandez-del Castillo, Carlos; Meireles, Ozanan

    2016-01-01

    The goal of telementoring is to recreate face-to-face encounters with a digital presence. Open-surgery telementoring is limited by lack of surgeon's point-of-view cameras. Google Glass is a wearable computer that looks like a pair of glasses but is equipped with wireless connectivity, a camera, and viewing screen for video conferencing. This study aimed to assess the safety of using Google Glass by assessing the video quality of a telementoring session. Thirty-four (n = 34) surgeons at a single institution were surveyed and blindly compared via video captured with Google Glass versus an Apple iPhone 5 during the open cholecystectomy portion of a Whipple. Surgeons were asked to evaluate the quality of the video and its adequacy for safe use in telementoring. Thirty-four of 107 invited surgical attendings (32%) responded to the anonymous survey. A total of 50% rated the Google Glass video as fair with the other 50% rating it as bad to poor. A total of 52.9% of respondents rated the Apple iPhone video as good. A significantly greater proportion of respondents felt Google Glass video quality was inadequate for telementoring versus the Apple iPhone's (82.4 vs 26.5%, p Google Glass provides a great breadth of functionality as a wearable device with two-way communication capabilities, current hardware limitations prevent its use as a telementoring device in surgery as the video quality is inadequate for safe telementoring. As the device is still in initial phases of development, future iterations or competitor devices may provide a better telementoring application for wearable devices.

  18. Endorsing good quality assurance practices in molecular pathology: risks and recommendations for diagnostic laboratories and external quality assessment providers.

    Science.gov (United States)

    Tembuyser, Lien; Dequeker, Elisabeth M C

    2016-01-01

    Quality assurance is an indispensable element in a molecular diagnostic laboratory. The ultimate goal is to warrant patient safety. Several risks that can compromise high quality procedures are at stake, from sample collection to the test performed by the laboratory, the reporting of test results to clinicians, and the organization of effective external quality assessment schemes. Quality assurance should therefore be safeguarded at each level and should imply a holistic multidisciplinary approach. This review aims to provide an overview of good quality assurance practices and discusses certain risks and recommendations to promote and improve quality assurance for both diagnostic laboratories and for external quality assessment providers. The number of molecular targets is continuously rising, and new technologies are evolving. As this poses challenges for clinical implementation and increases the demand for external quality assessment, the formation of an international association for improving quality assurance in molecular pathology is called for.

  19. Effects of music and music video interventions on sleep quality: A randomized controlled trial in adults with sleep disturbances.

    Science.gov (United States)

    Huang, Chiung-Yu; Chang, En-Ting; Hsieh, Yuan-Mei; Lai, Hui-Ling

    2017-10-01

    The present study aimed to compare the effects of music and music video interventions on objective and subjective sleep quality in adults with sleep disturbances. A randomized controlled trial was performed on 71 adults who were recruited from the outpatient department of a hospital with 1100 beds and randomly assigned to the control, music, and music video groups. During the 4 test days (Days 2-5), for 30min before nocturnal sleep, the music group listened to Buddhist music and the music video group watched Buddhist music videos. They were instructed to not listen/watch to the music/MV on the first night (pretest, Day 1) and the final night (Day 6). The control group received no intervention. Sleep was assessed using a one-channel electroencephalography machine in their homes and self-reported questionnaires. The music and music video interventions had no effect on any objective sleep parameters, as measured using electroencephalography. However, the music group had significantly longer subjective total sleep time than the music video group did (Wald χ 2 =6.23, p=0.04). Our study results increase knowledge regarding music interventions for sleep quality in adults with sleep disturbances. This study suggested that more research is required to strengthen the scientific knowledge of the effects of music intervention on sleep quality in adults with sleep disturbances. (ISRCTN94971645). Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Analysis of Video Signal Transmission Through DWDM Network Based on a Quality Check Algorithm

    Directory of Open Access Journals (Sweden)

    A. Markovic

    2013-04-01

    Full Text Available This paper provides an analysis of the multiplexed video signal transmission through the Dense Wavelength Division Multiplexing (DWDM network based on a quality check algorithm, which determines where the interruption of the transmission quality starts. On the basis of this algorithm, simulations of transmission for specific values of fiber parameters ​​ are executed. The analysis of the results shows how the BER and Q-factor change depends on the length of the fiber, i.e. on the number of amplifiers, and what kind of an effect the number of multiplexed channels and the flow rate per channel have on a transmited signals. Analysis of DWDM systems is performed in the software package OptiSystem 7.0, which is designed for systems with flow rates of 2.5 Gb/s and 10 Gb/s per channel.

  1. Application of Quality Assurance Strategies in Diagnostics and Clinical Support Services in Iranian Hospitals

    NARCIS (Netherlands)

    Aghaei Hashjin, Asgar; Kringos, Dionne; Ravaghi, Hamid; Manoochehri, Jila; Gorji, Hassan Abolghasem; Klazinga, Niek S.

    2015-01-01

    Background: Iran has a widespread diagnostics and clinical support services (DCSS) network that plays a crucial role in providing diagnostic and clinical support services to both inpatient and outpatient care. However, very little is known on the application of quality assurance (QA) policies in

  2. Diagnostic delay, quality of life and patient satisfaction among women diagnosed with endometrial or ovarian cancer

    DEFF Research Database (Denmark)

    Robinson, Kirstine M; Christensen, Karl Bang; Ottesen, Bent

    2012-01-01

    This study investigates the association between diagnostic delay (total delay), quality of life (QoL) and patient satisfaction, and the associations between QoL and patient satisfaction scores and survival for women diagnosed with ovarian or endometrial cancer.......This study investigates the association between diagnostic delay (total delay), quality of life (QoL) and patient satisfaction, and the associations between QoL and patient satisfaction scores and survival for women diagnosed with ovarian or endometrial cancer....

  3. Comprehensive Clinical Audits of Diagnostic Radiology Practices: A Tool for Quality Improvement. Quality Assurance Audit for Diagnostic Radiology Improvement and Learning (QUAADRIL)

    International Nuclear Information System (INIS)

    2010-01-01

    Interest in quality assurance processes and quality improvement in diagnostic radiology is being driven by a number of factors. These include the high cost and complexity of radiological equipment, acknowledgement of the possibility of increasing doses to patients, and the importance of radiological diagnosis to patient management within the health care environment. To acknowledge these interests, clinical audits have been introduced and, in Europe, mandated under a European Directive (Council Directive 97/47/EURATOM). Comprehensive clinical audits focus on clinical management and infrastructure, patient related and technical procedures, and education and research. This publication includes a structured set of standards appropriate for diagnostic radiology, an audit guide to their clinical review, and data collection sheets for the rapid production of reports in audit situations. It will be a useful guide for diagnostic radiology facilities wishing to improve their service to patients through timely diagnosis with minimal radiation dose.

  4. Comprehensive Clinical Audits of Diagnostic Radiology Practices: A Tool for Quality Improvement. Quality Assurance Audit for Diagnostic Radiology Improvement and Learning (QUAADRIL)

    International Nuclear Information System (INIS)

    2011-01-01

    Interest in quality assurance processes and quality improvement in diagnostic radiology is being driven by a number of factors. These include the high cost and complexity of radiological equipment, acknowledgement of the possibility of increasing doses to patients, and the importance of radiological diagnosis to patient management within the health care environment. To acknowledge these interests, clinical audits have been introduced and, in Europe, mandated under a European Directive (Council Directive 97/47/EURATOM). Comprehensive clinical audits focus on clinical management and infrastructure, patient related and technical procedures, and education and research. This publication includes a structured set of standards appropriate for diagnostic radiology, an audit guide to their clinical review, and data collection sheets for the rapid production of reports in audit situations. It will be a useful guide for diagnostic radiology facilities wishing to improve their service to patients through timely diagnosis with minimal radiation dose.

  5. Content-aware video quality assessment: predicting human perception of quality using peak signal to noise ratio and spatial/temporal activity

    Science.gov (United States)

    Ortiz-Jaramillo, B.; Niño-Castañeda, J.; Platiša, L.; Philips, W.

    2015-03-01

    Since the end-user of video-based systems is often a human observer, prediction of human perception of quality (HPoQ) is an important task for increasing the user satisfaction. Despite the large variety of objective video quality measures, one problem is the lack of generalizability. This is mainly due to the strong dependency between HPoQ and video content. Although this problem is well-known, few existing methods directly account for the influence of video content on HPoQ. This paper propose a new method to predict HPoQ by using simple distortion measures and introducing video content features in their computation. Our methodology is based on analyzing the level of spatio-temporal activity and combining HPoQ content related parameters with simple distortion measures. Our results show that even very simple distortion measures such as PSNR and simple spatio-temporal activity measures lead to good results. Results over four different public video quality databases show that the proposed methodology, while faster and simpler, is competitive with current state-of-the-art methods, i.e., correlations between objective and subjective assessment higher than 80% and it is only two times slower than PSNR.

  6. Digital CODEC for real-time processing of broadcast quality video signals at 1.8 bits/pixel

    Science.gov (United States)

    Shalkhauser, Mary JO; Whyte, Wayne A.

    1991-01-01

    Advances in very large scale integration and recent work in the field of bandwidth efficient digital modulation techniques have combined to make digital video processing technically feasible an potentially cost competitive for broadcast quality television transmission. A hardware implementation was developed for DPCM (differential pulse code midulation)-based digital television bandwidth compression algorithm which processes standard NTSC composite color television signals and produces broadcast quality video in real time at an average of 1.8 bits/pixel. The data compression algorithm and the hardware implementation of the codec are described, and performance results are provided.

  7. Interlayer Simplified Depth Coding for Quality Scalability on 3D High Efficiency Video Coding

    Directory of Open Access Journals (Sweden)

    Mengmeng Zhang

    2014-01-01

    Full Text Available A quality scalable extension design is proposed for the upcoming 3D video on the emerging standard for High Efficiency Video Coding (HEVC. A novel interlayer simplified depth coding (SDC prediction tool is added to reduce the amount of bits for depth maps representation by exploiting the correlation between coding layers. To further improve the coding performance, the coded prediction quadtree and texture data from corresponding SDC-coded blocks in the base layer can be used in interlayer simplified depth coding. In the proposed design, the multiloop decoder solution is also extended into the proposed scalable scenario for texture views and depth maps, and will be achieved by the interlayer texture prediction method. The experimental results indicate that the average Bjøntegaard Delta bitrate decrease of 54.4% can be gained in interlayer simplified depth coding prediction tool on multiloop decoder solution compared with simulcast. Consequently, significant rate savings confirm that the proposed method achieves better performance.

  8. Diagnostics

    DEFF Research Database (Denmark)

    Donné, A.J.H.; Costley, A.E.; Barnsley, R.

    2007-01-01

    In order to support the operation of ITER and the planned experimental programme an extensive set of plasma and first wall measurements will be required. The number and type of required measurements will be similar to those made on the present-day large tokamaks while the specification...... of the measurements—time and spatial resolutions, etc—will in some cases be more stringent. Many of the measurements will be used in the real time control of the plasma driving a requirement for very high reliability in the systems (diagnostics) that provide the measurements. The implementation of diagnostic systems......&D is needed to prepare the systems. In some cases the environmental difficulties are so severe that new diagnostic techniques are required. The starting point in the development of diagnostics for ITER is to define the measurement requirements and develop their justification. It is necessary to include all...

  9. An IEC standard on quality assurance for diagnostic X-ray systems

    International Nuclear Information System (INIS)

    Boer, J.A. den

    1985-01-01

    A presentation is given of some characteristics of the International Electrotechnical Commission (IEC). This is followed by a short discussion of general aspects of quality assurance in the diagnostic department. From this discussion it becomes apparent to which aspects of quality assurance IEC can contribute. Within that framework a working group of Sub-Committee 62 is at present active in developing a standard on quality assurance for diagnostic X-ray systems. The standard will contain a set of constancy tests that is claimed to allow a balanced quality assurance programme. The democratic procedure of IEC should guarantee that the proposed standard gains wide acceptance. (author)

  10. Traps in quality assurance of diagnostic X-ray equipment

    International Nuclear Information System (INIS)

    Meier, N.; Lenzen, H.; Fiebich, M.

    1992-01-01

    With the introduction of the German industrial protocol for quality assurance of X-ray equipment, everybody using X-ray machines fell into sort of trap or found some of the procedures misleading. Vigorous discussions were held on every conceivable aspect of this and other protocols, and are still in progress. This paper points out some of the common traps and considers a new type dosimeter, which allows a definite separation of quality assurance of X-ray equipment and of processing and which can also be used in future for quality assurance of digital radiography equipment. (orig.) [de

  11. Validation of the fifth edition BI-RADS ultrasound lexicon with comparison of fourth and fifth edition diagnostic performance using video clips

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jung Hyun; Kim, Min Jung; Lee, Hye Sun [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Sung Hun [Dept. of Radiology, Seoul St. Mary' s Hospital, The Catholic University of Korea, Seoul(Korea, Republic of); Youk, Ji Hyun [Dept. of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Jeong, Sun Hye [Dept. of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Kim, You Me [Dept. of Radiology, Dankook University Hospital, Dankook University College of Medicine, Cheonan (Korea, Republic of)

    2016-08-15

    The aim of this study was to evaluate the positive predictive value (PPV) and the diagnostic performance of the ultrasonographic descriptors in the fifth edition of BI-RADS, comparing with the fourth edition using video clips. From September 2013 to July 2014, 80 breast masses in 74 women (mean age, 47.5±10.7 years) from five institutions of the Korean Society of Breast Imaging were included. Two radiologists individually reviewed the static and video images and analyzed the images according to the fourth and fifth edition of BI-RADS. The PPV of each descriptor was calculated and diagnostic performances between the fourth and fifth editions were compared. Of the 80 breast masses, 51 (63.8%) were benign and 29 (36.2%) were malignant. Suspicious ultrasonographic features such as irregular shape, non-parallel orientation, angular or spiculated margins, and combined posterior features showed higher PPV in both editions (all P<0.05). No significant differences were found in the diagnostic performances between the two editions (all P>0.05). The area under the receiver operating characteristics curve was higher in the fourth edition (0.708 to 0.690), without significance (P=0.416). The fifth edition of the BI-RADS ultrasound lexicon showed comparable performance to the fourth edition and can be useful in the differential diagnosis of breast masses using ultrasonography.

  12. Moving beyond quality control in diagnostic radiology and the role of the clinically qualified medical physicist.

    Science.gov (United States)

    Delis, H; Christaki, K; Healy, B; Loreti, G; Poli, G L; Toroi, P; Meghzifene, A

    2017-09-01

    Quality control (QC), according to ISO definitions, represents the most basic level of quality. It is considered to be the snapshot of the performance or the characteristics of a product or service, in order to verify that it complies with the requirements. Although it is usually believed that "the role of medical physicists in Diagnostic Radiology is QC", this, not only limits the contribution of medical physicists, but is also no longer adequate to meet the needs of Diagnostic Radiology in terms of Quality. In order to assure quality practices more organized activities and efforts are required in the modern era of diagnostic radiology. The complete system of QC is just one element of a comprehensive quality assurance (QA) program that aims at ensuring that the requirements of quality of a product or service will consistently be fulfilled. A comprehensive Quality system, starts even before the procurement of any equipment, as the need analysis and the development of specifications are important components under the QA framework. Further expanding this framework of QA, a comprehensive Quality Management System can provide additional benefits to a Diagnostic Radiology service. Harmonized policies and procedures and elements such as mission statement or job descriptions can provide clarity and consistency in the services provided, enhancing the outcome and representing a solid platform for quality improvement. The International Atomic Energy Agency (IAEA) promotes this comprehensive quality approach in diagnostic imaging and especially supports the field of comprehensive clinical audits as a tool for quality improvement. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  13. Subjective quality of videos displayed with local backlight dimming at different peak white and ambient light levels

    DEFF Research Database (Denmark)

    Mantel, Claire; Korhonen, Jari; Forchhammer, Søren

    2015-01-01

    In this paper the influence of ambient light and peak white (maximum brightness) of a display on the subjective quality of videos shown with local backlight dimming is examined. A subjective experiment investigating those factors is set-up using high contrast test sequences. The results are firstly...

  14. Constancy check of beam quality in conventional diagnostic X-ray equipment

    International Nuclear Information System (INIS)

    Costa, Alessandro M.; Badin, Romulo S.; Leite, Marina S.; Caldas, Linda V.E.

    2008-01-01

    A tandem ionization chamber was developed for quality control programs of X-ray equipment used in conventional radiography and mammography. A methodology for the use of the tandem chamber in the constancy check of diagnostic X-ray beam qualities was established. The application at a medical X-ray imaging facility of this established methodology is presented. The use of the tandem chamber in the constancy check of diagnostic X-ray beam qualities is a useful method to control the performance of the X-ray equipment

  15. Quality assurance for diagnostic X-ray machines in Tanzania

    International Nuclear Information System (INIS)

    Sungita, Y.Y.; Mdoe, S.L.; Ngatunga, J.; Kitosi, A.E.; Muhogora, W.E.

    1998-01-01

    In this presentation it is being discussed a close relationship between the prevention of accidents involving apparatus that generates the ionizing radiation (x-ray tubes etc.) and the need to perform quality control procedures and make follow-up corrective maintenance procedures. A summary of results of quality control performance of x-ray machines in certain centers in Tanzania is tabled and measures to overcome some of the observed problems are recommended. The number of X-ray units inspected were 219, out of which 123 were working, 75 were out of order, 6 units were not yet installed and those which are working with faulty parts were 15. The performance of quality assurance for X-Ray units (57) tested showed that 36.8% didn't qualify. About 80% of these equipment are more than 15 years old. (author)

  16. Challenges in setting up quality control in diagnostic radiology ...

    African Journals Online (AJOL)

    Background: The Nigerian Nuclear Regulatory Authority (NNRA) was established to regulate and control the use of radioactive and radiation emitting sources ... Method: Some quality control tests (output, exposure linearity and reproducibility) were measured on the x-ray machines in the facilities that took part in the study.

  17. A Methodology for Anatomic Ultrasound Image Diagnostic Quality Assessment

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian; Lange, Theis; Brandt, Andreas Hjelm

    2017-01-01

    This paper discusses methods for assessment of ultrasound image quality based on our experiences with evaluating new methods for anatomic imaging. It presents a methodology to ensure a fair assessment between competing imaging methods using clinically relevant evaluations. The methodology...... to properly reveal the clinical value. The paper exemplifies the methodology using recent studies of Synthetic Aperture Sequential Beamforming tissue harmonic imaging....

  18. Magnetic resonance enterography with oral mannitol solution: Diagnostic efficacy and image quality in Crohn disease.

    Science.gov (United States)

    Koplay, M; Guneyli, S; Cebeci, H; Korkmaz, H; Emiroglu, H H; Sekmenli, T; Paksoy, Y

    2017-12-01

    The aim of this study was to investigate the diagnostic efficacy and image quality of magnetic resonance enterography (MRE) using oral mannitol solution for the evaluation Crohn disease (CD). We retrospectively evaluated MRE examinations of 153 patients with an assumed or definitive diagnosis of CD. There were 65 men and 88 women, with a mean age of 35.7 years (range: 6-73years). MRE findings of the patients were compared to histopathologic results obtained by surgery-fiberoptic endoscopy. The sensitivity, specificity and diagnostic efficacy rate were calculated. Additionally, image quality of MRE was evaluated using a four-point scale (1=excellent, 4=poor/non-diagnostic). Sensitivity, specificity and diagnostic efficacy were 92.5%, 93% and 92.8%, respectively. Six patients had false-positive and five patients had false-negative findings. Three falsely positive patients had ulcerative colitis and three had non-specific terminal ileitis. A total of 765 small bowel segments were analyzed; 475 (62%) had an image quality score of 1 and 15 (2%), an image quality score of 4. MRE using oral mannitol solution provides excellent image quality for MRE and has high degrees of diagnostic efficacy in CD patients. Copyright © 2017 Editions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  19. Modeling the Quality of Videos Displayed With Local Dimming Backlight at Different Peak White and Ambient Light Levels

    DEFF Research Database (Denmark)

    Mantel, Claire; Søgaard, Jacob; Bech, Søren

    2016-01-01

    This paper investigates the impact of ambient light and peak white (maximum brightness of a display) on the perceived quality of videos displayed using local backlight dimming. Two subjective tests providing quality evaluations are presented and analyzed. The analyses of variance show significant...... interactions of the factors peak white and ambient light with the perceived quality. Therefore, we proceed to predict the subjective quality grades with objective measures. The rendering of the frames on liquid crystal displays with light emitting diodes backlight at various ambient light and peak white levels...

  20. Quality assurance in X-ray diagnostic radiology - Report II

    International Nuclear Information System (INIS)

    Fosmark, H.; Rozycki, Z.

    1987-01-01

    In the context of an analysis of technical quality assurance in Norwegian X-ray departments, a survey has been carried out in 21 laboratories in 4 hospitals. The tests were restricted to equipment used in general radiography, and the parameters analysed were of kV (using an electronic penetrameter), exposure time, waveform, output and automatic exposure control systems. In addition, a trial to compare overall performance in radiography and fluoroscopy was performed with a PMMP test phantom (SPRI). The survey is presented in two reports. The first one covers details of procedures and equipment. In this second report results are given and discussed. The results show that most of the equipment does function satifactorily, but also demonstrate the need to introduce quality assurance in X-ray departments

  1. Quality Control in diagnostic radiology according to national regulations

    International Nuclear Information System (INIS)

    Domienik, J.; Chruscielewski, W.; Jankowski, J.

    2006-01-01

    The aim of the paper is to review the main aspects of quality control of radiological devices according to the current national regulations. Explanation of the physical principles of image formation by different test phantoms used to measure focal spot sizes is presented in appendix. The obligation for quality assurance (QA) for all X-ray systems which follows European standards was enforced in updated '' Atomic Law Act '' of 29 November 2000 . This document is the main regulatory act which establishes the basic safety standards for radiation protection in Poland. The main modifications introduced by this new Act concerned the issue of radiation protection of individuals undergoing medical examinations with the use of ionizing radiation which is regulated by EC Directive 97/43 Euratom. According to this Directive quality assurance programmes, including quality control measures need to be implemented by the holder of the radiological installation. Therefore, in the above Act the Minister of Health has been obligated to impose specific regulations describing the way of implementation of general principles laid down in the Directive. Some of these regulations, like those concerning QC tests and tolerances, have already been mentioned in the document titled '' On the conditions for safe application of ionizing radiation in medicine ''. For example, the QC program in radiography is being considered; the obligatory tests- acceptance, routine and annual- are discussed and specific procedures are being indicated. The main idea of the document '' On the conditions for safe application of ionizing radiation in medicine '' which concerns radiation protection of patients and staff against ionizing radiation used in medicine is to implement the surveillance of all X-ray systems in form of acceptance tests followed by internal tests (routine and annual) performed in accordance with European standards. (author)

  2. Radiation exposure and image quality in x-Ray diagnostic radiology physical principles and clinical applications

    CERN Document Server

    Aichinger, Horst; Joite-Barfuß, Sigrid; Säbel, Manfred

    2012-01-01

    The largest contribution to radiation exposure to the population as a whole arises from diagnostic X-rays. Protecting the patient from radiation is a major aim of modern health policy, and an understanding of the relationship between radiation dose and image quality is of pivotal importance in optimising medical diagnostic radiology. In this volume the data provided for exploring these concerns are partly based on X-ray spectra, measured on diagnostic X-ray tube assemblies, and are supplemented by the results of measurements on phantoms and simulation calculations.

  3. Quality assurance in diagnostic radiology: a guide for state program implementation

    International Nuclear Information System (INIS)

    1981-01-01

    Efforts to reduce unnecessary radiation exposure in the healing arts and minimize health care costs have been stressed by Federal agencies, professional societies and individual States for the past several years. A method to achieve this goal was developed in the early 1970's and tested extensively since then. This method is referred to as 'Quality Assurance,' (Q.A.). Realizing the potential benefits of implementing quality assurance in diagnostic x-ray facilities, the Conference of Radiation Control Program Directors' Executive Board authorized the formation of a task force in 1976 to study various aspects of Q.A. The specific changes given the task force were: To define the areas that use diagnostic x-ray which require quality assurance and to describe the basic factors to be included in quality assurance programs. To examine current diagnostic x-ray quality assurance programs in Federal agencies and serve as a focal point for State input into these programs. To report to the Conference on quality assurance programs and techniques that could be utilized by the State radiation programs. This document is designed to educate State program personnel in the concepts of Q.A. and to encourage them to assist medical diagnostic x-ray facilities in implementing Q.A

  4. Software for creating quality control database in diagnostic radiology

    International Nuclear Information System (INIS)

    Stoeva, M.; Spassov, G.; Tabakov, S.

    2000-01-01

    The paper describes a PC based program with database for quality control (QC). It keeps information about all surveyed equipment and measured parameters. The first function of the program is to extract information from old (existing) MS Excel spreadsheets with QC surveys. The second function is used for input of measurements which are automatically organized in MS Excel spreadsheets and built into the database. The spreadsheets are based on the protocols described in the EMERALD Training Scheme. In addition, the program can make statistics of all measured parameters, both in absolute term and in time

  5. Diagnostic Accuracy of Global Pharma Health Fund Minilab™ in Assessing Pharmacopoeial Quality of Antimicrobials.

    Science.gov (United States)

    Pan, Hui; Ba-Thein, William

    2018-01-01

    Global Pharma Health Fund (GPHF) Minilab™, a semi-quantitative thin-layer chromatography (TLC)-based commercially available test kit, is widely used in drug quality surveillance globally, but its diagnostic accuracy is unclear. We investigated the diagnostic accuracy of Minilab system for antimicrobials, using high-performance liquid chromatography (HPLC) as reference standard. Following the Minilab protocols and the Pharmacopoeia of the People's Republic of China protocols, Minilab-TLC and HPLC were used to test five common antimicrobials (506 batches) for relative concentration of active pharmaceutical ingredients. The prevalence of poor-quality antimicrobials determined, respectively, by Minilab TLC and HPLC was amoxicillin (0% versus 14.9%), azithromycin (0% versus 17.4%), cefuroxime axetil (14.3% versus 0%), levofloxacin (0% versus 3.0%), and metronidazole (0% versus 38.0%). The Minilab TLC had false-positive and false-negative detection rates of 2.6% (13/506) and 15.2% (77/506) accordingly, resulting in the following test characteristics: sensitivity 0%, specificity 97.0%, positive predictive value 0, negative predictive value 0.8, positive likelihood ratio 0, negative likelihood ratio 1.0, diagnostic odds ratio 0, and adjusted diagnostic odds ratio 0.2. This study demonstrates unsatisfying diagnostic accuracy of Minilab system in screening poor-quality antimicrobials of common use. Using Minilab as a stand-alone system for monitoring drug quality should be reconsidered.

  6. The influence of probiotics on the cervical malignancy diagnostics quality.

    Science.gov (United States)

    Perisić, Zivko; Perisić, Natasa; Golocorbin Kon, Svetlana; Vesović, Dusan; Jovanović, Ana Mitrović; Mikov, Momir

    2011-11-01

    -infective agents provides more reliable cytological diagnostics, reduces the number of false positive and false negative findings on cervical malignancy and normalizes vaginal microflora in higher percentage of patients with vaginal infections comapred with therapy including antiinfective agents only.

  7. Validation of the fifth edition BI-RADS ultrasound lexicon with comparison of fourth and fifth edition diagnostic performance using video clips.

    Science.gov (United States)

    Yoon, Jung Hyun; Kim, Min Jung; Lee, Hye Sun; Kim, Sung Hun; Youk, Ji Hyun; Jeong, Sun Hye; Kim, You Me

    2016-10-01

    The aim of this study was to evaluate the positive predictive value (PPV) and the diagnostic performance of the ultrasonographic descriptors in the fifth edition of BI-RADS, comparing with the fourth edition using video clips. From September 2013 to July 2014, 80 breast masses in 74 women (mean age, 47.5±10.7 years) from five institutions of the Korean Society of Breast Imaging were included. Two radiologists individually reviewed the static and video images and analyzed the images according to the fourth and fifth edition of BI-RADS. The PPV of each descriptor was calculated and diagnostic performances between the fourth and fifth editions were compared. Of the 80 breast masses, 51 (63.8%) were benign and 29 (36.2%) were malignant. Suspicious ultrasonographic features such as irregular shape, non-parallel orientation, angular or spiculated margins, and combined posterior features showed higher PPV in both editions (all P0.05). The area under the receiver operating characteristics curve was higher in the fourth edition (0.708 to 0.690), without significance (P=0.416). The fifth edition of the BI-RADS ultrasound lexicon showed comparable performance to the fourth edition and can be useful in the differential diagnosis of breast masses using ultrasonography.

  8. Validation of the fifth edition BI-RADS ultrasound lexicon with comparison of fourth and fifth edition diagnostic performance using video clips

    Directory of Open Access Journals (Sweden)

    Jung Hyun Yoon

    2016-10-01

    Full Text Available Purpose The aim of this study was to evaluate the positive predictive value (PPV and the diagnostic performance of the ultrasonographic descriptors in the fifth edition of BI-RADS, comparing with the fourth edition using video clips. Methods From September 2013 to July 2014, 80 breast masses in 74 women (mean age, 47.5±10.7 years from five institutions of the Korean Society of Breast Imaging were included. Two radiologists individually reviewed the static and video images and analyzed the images according to the fourth and fifth edition of BI-RADS. The PPV of each descriptor was calculated and diagnostic performances between the fourth and fifth editions were compared. Results Of the 80 breast masses, 51 (63.8% were benign and 29 (36.2% were malignant. Suspicious ultrasonographic features such as irregular shape, non-parallel orientation, angular or spiculated margins, and combined posterior features showed higher PPV in both editions (all P0.05. The area under the receiver operating characteristics curve was higher in the fourth edition (0.708 to 0.690, without significance (P=0.416. Conclusion The fifth edition of the BI-RADS ultrasound lexicon showed comparable performance to the fourth edition and can be useful in the differential diagnosis of breast masses using ultrasonography.

  9. The influence of probiotics on the cervical malignancy diagnostics quality

    Directory of Open Access Journals (Sweden)

    Perišić Živko

    2011-01-01

    GR-1 and Lactobacillus reuteri RC-14 concomitantly with specific antiinfective agents provides more reliable cytological diagnostics, reduces the number of false positive and false negative findings on cervical malignancy and normalizes vaginal microflora in higher percentage of patients with vaginal infections comapred with therapy including anti-infective agents only.

  10. Management of quality assurance in diagnostic radiology by microcomputer

    International Nuclear Information System (INIS)

    Evans, S.H.

    1985-01-01

    Software has been written for the calculation, interpretation and presentation of quality control measurements of X-ray machines. The programs run on a Z80 based microcomputer system comprising a Comart Communicator CP500 interfaced to a Volker Craig 4404 visual display unit (VDU) and an EpsonMX80F/T printer. The software has been written in the dbaseII database language (Ashton Tate 1975) and it runs under the CP/M operating system. The programs guide the user through each routine required and can be operated without knowledge of computers. The programs calculate the results from the raw data obtained from the test equipment and these results are then stored and analysed. (U.K.)

  11. Development of Tandem ionization chambers for use in quality control programs in radiotherapy and diagnostic radiology

    International Nuclear Information System (INIS)

    Costa, Alessandro Martins da

    2003-01-01

    A quality control program of X-ray equipment used in diagnostic radiology and radiotherapy requires the check of the beam qualities constancy in terms of the half-value layers. In this work, two special double-faced parallel-plate ionization chambers were developed with inner electrodes of different materials, in tandem system. The different energy response of the two faces of each chamber allowed the development of tandem systems useful for the check of beam qualities constancy. The main application of these ionization chambers will be in quality control programs of diagnostic and therapeutic X-ray equipment for confirmation of half-value layers previously determined by the conventional method. Moreover, the tandem chambers may also be utilized for measurements of air kerma values (and air kerma rates) in kilo voltage X-radiation fields used for diagnostic and therapeutic procedures. The chambers were studied in relation to their operational characteristics, and they were calibrated in X-ray beams in accordance to international recommendations. They presented a very good level of performance. In this developed system no absorbers or special set-ups are necessary. A methodology of use of the chambers in the quality control of diagnostic and therapeutic X-ray systems was established, with the elaboration of the respective procedures. (author)

  12. Enhancing Perceived Quality of Compressed Images and Video with Anisotropic Diffusion and Fuzzy Filtering

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Korhonen, Jari; Forchhammer, Søren

    2013-01-01

    and subjective results on JPEG compressed images, as well as MJPEG and H.264/AVC compressed video, indicate that the proposed algorithms employing directional and spatial fuzzy filters achieve better artifact reduction than other methods. In particular, robust improvements with H.264/AVC video have been gained...

  13. Can video improve grant review quality and lead to more reliable ranking?

    Directory of Open Access Journals (Sweden)

    Michael Doran

    2017-02-01

    Full Text Available Multimedia video is rapidly becoming mainstream, and many studies indicate that it is a more effective communication medium than text. In this project we AIM to test if videos can be used, in place of text-based grant proposals, to improve communication and increase the reliability of grant ranking. We will test if video improves reviewer comprehension (AIM 1, if external reviewer grant scores are more consistent with video (AIM 2, and if mock Australian Research Council (ARC panels award more consistent scores when grants are presented as videos (AIM 3. This will be the first study to evaluate the use of video in this application. The ARC reviewed over 3500 Discovery Project applications in 2015, awarding 635 Projects. Selecting the “best” projects is extremely challenging. This project will improve the selection process by facilitating the transition from text-based to video-based proposals. The impact could be profound: Improved video communication should streamline the grant preparation and review processes, enable more reliable ranking of applications, and more accurate identification of the “next big innovations”.

  14. Resolution enhancement of low quality videos using a high-resolution frame

    NARCIS (Netherlands)

    Pham, T.Q.; Van Vliet, L.J.; Schutte, K.

    2006-01-01

    This paper proposes an example-based Super-Resolution (SR) algorithm of compressed videos in the Discrete Cosine Transform (DCT) domain. Input to the system is a Low-Resolution (LR) compressed video together with a High-Resolution (HR) still image of similar content. Using a training set of

  15. A system for diagnostic quality radiographic alignment of radiotherapy patients

    International Nuclear Information System (INIS)

    Gall, Kenneth P.; Zygmanski, Piotr; Thornton, Allan F.

    1996-01-01

    Purpose In order to achieve highly accurate positioning of radiotherapy patients treated on a standard fractionation schedule we have developed a digital imaging system and associated repositioning algorithms. The system is efficient enough that it is usable on a routine basis. The system is intended to allow stereotactic level precision of patient positioning in fractionated therapy which in turn allows treatment fields to be designed with tighter margins. This may allow higher target doses to be delivered and thereby higher local control to be achieved for certain classes of patients. Materials and Methods Patients to be treated under a standard fractionation schedule for intracranial or head and neck targets have a set of three radiopaque fiducial markers implanted in the outer table of the skull. As part of the 3 dimensional treatment plan the locations of the fiducial markers is determined on the planning CT scan. The positions of the markers relative to the beam direction and isocenter constitute a 3 dimensional position prescription for the treatment. At the time of treatment a pair of orthogonal images is obtained with diagnostic xray tubes aligned to isocenter and a digital imaging system. The imaging system consists of a thermoelectrically cooled CCD camera which views a Gadolinium based xray intensifying screen. The field of view of the imager is 30 x 30 cm which gives a 1.5 lp/mm spatial resolution at isocenter using a 1.5 xray magnification geometry. The user identifies the approximate position of the fiducial markers on the digital image using a mouse and a standard PC computer running an imaging software routine. The identified area is then analyzed to determine the projected position of the marker with sub-pixel (<0.5mm) accuracy. An algorithm based on rigid body transformations computes the three dimensional realignment motions necessary to bring the patient to the desired position for treatment. Results We have been using a system to reposition

  16. Evaluating radiographers' diagnostic accuracy in screen-reading mammograms: what constitutes a quality study?

    International Nuclear Information System (INIS)

    Debono, Josephine C; Poulos, Ann E

    2015-01-01

    The aim of this study was to first evaluate the quality of studies investigating the diagnostic accuracy of radiographers as mammogram screen-readers and then to develop an adapted tool for determining the quality of screen-reading studies. A literature search was used to identify relevant studies and a quality evaluation tool constructed by combining the criteria for quality of Whiting, Rutjes, Dinnes et al. and Brealey and Westwood. This constructed tool was then applied to the studies and subsequently adapted specifically for use in evaluating quality in studies investigating diagnostic accuracy of screen-readers. Eleven studies were identified and the constructed tool applied to evaluate quality. This evaluation resulted in the identification of quality issues with the studies such as potential for bias, applicability of results, study conduct, reporting of the study and observer characteristics. An assessment of the applicability and relevance of the tool for this area of research resulted in adaptations to the criteria and the development of a tool specifically for evaluating diagnostic accuracy in screen-reading. This tool, with further refinement and rigorous validation can make a significant contribution to promoting well-designed studies in this important area of research and practice

  17. WE-AB-206-01: Diagnostic Ultrasound Imaging Quality Assurance

    Energy Technology Data Exchange (ETDEWEB)

    Zagzebski, J. [University of Wisconsin (United States)

    2016-06-15

    The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.

  18. Quality-of-Life Differences among Diagnostic Subgroups of Children Receiving Ventilating Tubes for Otitis Media

    DEFF Research Database (Denmark)

    Heidemann, Christian Hamilton; Lauridsen, Henrik Hein; Kjeldsen, Anette Drøhse

    2015-01-01

    OBJECTIVE: The pathological picture may differ considerably between diagnostic subgroups of children with otitis media receiving ventilating tubes. The aims of this study are to investigate differences in quality of life among diagnostic subgroups of children treated with ventilating tubes...... and to investigate possible predictors for clinical success. STUDY DESIGN: Longitudinal observational study. SETTING: Secondary care units. METHODS: Four hundred ninety-one families were enrolled in the study. The Otitis Media-6 questionnaire was applied in the assessment of child quality of life. Caregivers...... completed questionnaires at 7 time points from before treatment to 18-month follow-up. Logistic regression analysis was used to investigate possible predictors for clinical success. RESULTS: Response rates ranged from 96% to 81%; diagnostic distribution: 15% recurrent acute otitis media (rAOM), 47% otitis...

  19. Evaluation of QUADAS, a tool for the quality assessment of diagnostic accuracy studies

    NARCIS (Netherlands)

    Whiting, Penny F.; Weswood, Marie E.; Rutjes, Anne W. S.; Reitsma, Johannes B.; Bossuyt, Patrick N. M.; Kleijnen, Jos

    2006-01-01

    BACKGROUND: A quality assessment tool for diagnostic accuracy studies, named QUADAS, has recently been developed. Although QUADAS has been used in several systematic reviews, it has not been formally validated. The objective was to evaluate the validity and usefulness of QUADAS. METHODS: Three

  20. Dose and diagnostic image quality in digital tomosynthesis imaging of facial bones in pediatrics

    Science.gov (United States)

    King, J. M.; Hickling, S.; Elbakri, I. A.; Reed, M.; Wrogemann, J.

    2011-03-01

    The purpose of this study was to evaluate the use of digital tomosynthesis (DT) for pediatric facial bone imaging. We compared the eye lens dose and diagnostic image quality of DT facial bone exams relative to digital radiography (DR) and computed tomography (CT), and investigated whether we could modify our current DT imaging protocol to reduce patient dose while maintaining sufficient diagnostic image quality. We measured the dose to the eye lens for all three modalities using high-sensitivity thermoluminescent dosimeters (TLDs) and an anthropomorphic skull phantom. To assess the diagnostic image quality of DT compared to the corresponding DR and CT images, we performed an observer study where the visibility of anatomical structures in the DT phantom images were rated on a four-point scale. We then acquired DT images at lower doses and had radiologists indicate whether the visibility of each structure was adequate for diagnostic purposes. For typical facial bone exams, we measured eye lens doses of 0.1-0.4 mGy for DR, 0.3-3.7 mGy for DT, and 26 mGy for CT. In general, facial bone structures were visualized better with DT then DR, and the majority of structures were visualized well enough to avoid the need for CT. DT imaging provides high quality diagnostic images of the facial bones while delivering significantly lower doses to the lens of the eye compared to CT. In addition, we found that by adjusting the imaging parameters, the DT effective dose can be reduced by up to 50% while maintaining sufficient image quality.

  1. An Analysis of Quality of Service (QoS In Live Video Streaming Using Evolved HSPA Network Media

    Directory of Open Access Journals (Sweden)

    Achmad Zakaria Azhar

    2016-10-01

    Full Text Available Evolved High Speed Packet Access (HSPA+ is a mobile telecommunication system technology and the evolution of HSPA technology. This technology has a packet data based service with downlink speeds up to 21.1 Mbps and uplink speed up to 11.5 Mbps on the bandwidth 5MHz. This technology is expected to fulfill and support the needs for information that involves all aspects of multimedia such as video and audio, especially live video streaming. By utilizing this technology it will facilitate communicating the information, for example to monitoring the situation of the house, the news coverage at some certain area, and other events in real time. This thesis aims to identify and test the Quality of Service (QoS performance on the network that is used for live video streaming with the parameters of throughput, delay, jitter and packet loss. The software used for monitoring the data traffic of the live video streaming network is wireshark network analyzer. From the test results it is obtained that the average throughput of provider B is 5,295 Kbps bigger than the provider A, the average delay of provider B is 0.618 ms smaller than the provider A, the average jitter of provider B is 0.420 ms smaller than the provider A and the average packet loss of provider B is 0.451% smaller than the provider A.

  2. Training value of laparoscopic colorectal videos on the World Wide Web: a pilot study on the educational quality of laparoscopic right hemicolectomy videos.

    Science.gov (United States)

    Celentano, V; Browning, M; Hitchins, C; Giglio, M C; Coleman, M G

    2017-11-01

    Instructive laparoscopy videos with appropriate exposition could be ideal for initial training in laparoscopic surgery, but unfortunately there are no guidelines for annotating these videos or agreed methods to measure the educational content and the safety of the procedure presented. Aim of this study is to systematically search the World Wide Web to determine the availability of laparoscopic colorectal surgery videos and to objectively establish their potential training value. A search for laparoscopic right hemicolectomy videos was performed on the three most used English language web search engines Google.com, Bing.com, and Yahoo.com; moreover, a survey among 25 local trainees was performed to identify additional websites for inclusion. All laparoscopic right hemicolectomy videos with an English language title were included. Videos of open surgery, single incision laparoscopic surgery, robotic, and hand-assisted surgery were excluded. The safety of the demonstrated procedure was assessed with a validated competency assessment tool specifically designed for laparoscopic colorectal surgery and data on the educational content of the video were extracted. Thirty-one websites were identified and 182 surgical videos were included. One hundred and seventy-three videos (95%) detailed the year of publication; this demonstrated a significant increase in the number of videos published per year from 2009. Characteristics of the patient were rarely presented, only 10 videos (5.4%) reported operating time and only 6 videos (3.2%) reported 30-day morbidity; 34 videos (18.6%) underwent a peer-review process prior to publication. Formal case presentation, the presence of audio narration, the use of diagrams, and snapshots and a step-by-step approach are all characteristics of peer-reviewed videos but no significant difference was found in the safety of the procedure. Laparoscopic videos can be a useful adjunct to operative training. There is a large and increasing amount of

  3. Video over cognitive radio networks when quality of service meets spectrum

    CERN Document Server

    Mao, Shiwen

    2014-01-01

    This book focuses on the problem of video streaming over emerging cognitive radio (CR) networks. The book discusses the problems and techniques for scalable video streaming over cellular cognitive radio networks, ad hoc CR networks, cooperative CR networks, and femtocell CR networks. The author formulates these problems and proposes optimal algorithms to solve these problems. Also, the book analyzes the proposed algorithms and validates the algorithms with simulations.

  4. An overview of the International Electrotechnical Commission's activities on quality assurance in diagnostic radiology

    International Nuclear Information System (INIS)

    Julius, H.W.; Ammers, H. van; Henshaw, E.T.

    1989-01-01

    In 1981, the International Electrotechnical Commission Sub-committee 62B set up a Working Group (WG 10) to deal with quality assurance in diagnostic X-ray departments and, more specifically, to develop international standards describing procedures to test the constancy of parameters of diagnostic X-ray installations. Since then, the working group has produced a report on General Aspects of Quality Assurance in Diagnostic X-ray Departments and four draft standards on specific topics, while seven more documents are in advanced drafting stage. Several others are presently under consideration. According to the approach adopted by the Working Group, these documents are meant to assist in establishing quality assurance programmes in hospitals and provide guidance on how to perform the tests and interpret their results. This paper reveals the general philosophy behind the activities of the Working Group as well as some details of the standard produced so far, with emphasis on the physical parameters of diagnostic X-ray installations and their proposed criteria for satisfactory performance. (author)

  5. Miniaturized video-microscopy system for near real-time water quality biomonitoring using microfluidic chip-based devices

    Science.gov (United States)

    Huang, Yushi; Nigam, Abhimanyu; Campana, Olivia; Nugegoda, Dayanthi; Wlodkowic, Donald

    2016-12-01

    Biomonitoring studies apply biological responses of sensitive biomonitor organisms to rapidly detect adverse environmental changes such as presence of physic-chemical stressors and toxins. Behavioral responses such as changes in swimming patterns of small aquatic invertebrates are emerging as sensitive endpoints to monitor aquatic pollution. Although behavioral responses do not deliver information on an exact type or the intensity of toxicants present in water samples, they could provide orders of magnitude higher sensitivity than lethal endpoints such as mortality. Despite the advantages of behavioral biotests performed on sentinel organisms, their wider application in real-time and near realtime biomonitoring of water quality is limited by the lack of dedicated and automated video-microscopy systems. Current behavioral analysis systems rely mostly on static test conditions and manual procedures that are time-consuming and labor intensive. Tracking and precise quantification of locomotory activities of multiple small aquatic organisms requires high-resolution optical data recording. This is often problematic due to small size of fast moving animals and limitations of culture vessels that are not specially designed for video data recording. In this work, we capitalized on recent advances in miniaturized CMOS cameras, high resolution optics and biomicrofluidic technologies to develop near real-time water quality sensing using locomotory activities of small marine invertebrates. We present proof-of-concept integration of high-resolution time-resolved video recording system and high-throughput miniaturized perfusion biomicrofluidic platform for optical tracking of nauplii of marine crustacean Artemia franciscana. Preliminary data demonstrate that Artemia sp. exhibits rapid alterations of swimming patterns in response to toxicant exposure. The combination of video-microscopy and biomicrofluidic platform facilitated straightforward recording of fast moving objects. We

  6. How and when do expert emergency physicians generate and evaluate diagnostic hypotheses? A qualitative study using head-mounted video cued-recall interviews.

    Science.gov (United States)

    Pelaccia, Thierry; Tardif, Jacques; Triby, Emmanuel; Ammirati, Christine; Bertrand, Catherine; Dory, Valérie; Charlin, Bernard

    2014-12-01

    The ability to make a diagnosis is a crucial skill in emergency medicine. Little is known about the way emergency physicians reach a diagnosis. This study aims to identify how and when, during the initial patient examination, emergency physicians generate and evaluate diagnostic hypotheses. We carried out a qualitative research project based on semistructured interviews with emergency physicians. The interviews concerned management of an emergency situation during routine medical practice. They were associated with viewing the video recording of emergency situations filmed in an "own-point-of-view" perspective. The emergency physicians generated an average of 5 diagnostic hypotheses. Most of these hypotheses were generated before meeting the patient or within the first 5 minutes of the meeting. The hypotheses were then rank ordered within the context of a verification procedure based on identifying key information. These tasks were usually accomplished without conscious effort. No hypothesis was completely confirmed or refuted until the results of investigations were available. The generation and rank ordering of diagnostic hypotheses is based on the activation of cognitive processes, enabling expert emergency physicians to process environmental information and link it to past experiences. The physicians seemed to strive to avoid the risk of error by remaining aware of the possibility of alternative hypotheses as long as they did not have the results of investigations. Understanding the diagnostic process used by emergency physicians provides interesting ideas for training residents in a specialty in which the prevalence of reasoning errors leading to incorrect diagnoses is high. Copyright © 2014 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  7. Perceptual quality estimation of H.264/AVC videos using reduced-reference and no-reference models

    Science.gov (United States)

    Shahid, Muhammad; Pandremmenou, Katerina; Kondi, Lisimachos P.; Rossholm, Andreas; Lövström, Benny

    2016-09-01

    Reduced-reference (RR) and no-reference (NR) models for video quality estimation, using features that account for the impact of coding artifacts, spatio-temporal complexity, and packet losses, are proposed. The purpose of this study is to analyze a number of potentially quality-relevant features in order to select the most suitable set of features for building the desired models. The proposed sets of features have not been used in the literature and some of the features are used for the first time in this study. The features are employed by the least absolute shrinkage and selection operator (LASSO), which selects only the most influential of them toward perceptual quality. For comparison, we apply feature selection in the complete feature sets and ridge regression on the reduced sets. The models are validated using a database of H.264/AVC encoded videos that were subjectively assessed for quality in an ITU-T compliant laboratory. We infer that just two features selected by RR LASSO and two bitstream-based features selected by NR LASSO are able to estimate perceptual quality with high accuracy, higher than that of ridge, which uses more features. The comparisons with competing works and two full-reference metrics also verify the superiority of our models.

  8. A comparison of the quality of image acquisition between the incident dark field and sidestream dark field video-microscopes.

    Science.gov (United States)

    Gilbert-Kawai, Edward; Coppel, Jonny; Bountziouka, Vassiliki; Ince, Can; Martin, Daniel

    2016-01-21

    The 'Cytocam' is a third generation video-microscope, which enables real time visualisation of the in vivo microcirculation. Based upon the principle of incident dark field (IDF) illumination, this hand held computer-controlled device was designed to address the technical limitations of its predecessors, orthogonal polarization spectroscopy and sidestream dark field (SDF) imaging. In this manuscript, we aimed to compare the quality of sublingual microcirculatory image acquisition between the IDF and SDF devices. Using the microcirculatory image quality scoring (MIQS) system, (six categories scored as either 0 = optimal, 1 = acceptable, or 10 = unacceptable), two independent raters compared 30 films acquired using the Cytocam IDF video-microscope, to an equal number obtained with an SDF device. Blinded to the origin of the films, the raters were therefore able to score between 0 and 60 for each film analysed. The scores' distributions between the two techniques were compared. The median MIQS (95% CI) given to the SDF camera was 7 (1.5-12), as compared to 1 (0.5-1.0) for the IDF device (p microscope, as compared to the SDF video-microscope.

  9. MATIN: A Random Network Coding Based Framework for High Quality Peer-to-Peer Live Video Streaming

    Science.gov (United States)

    Barekatain, Behrang; Khezrimotlagh, Dariush; Aizaini Maarof, Mohd; Ghaeini, Hamid Reza; Salleh, Shaharuddin; Quintana, Alfonso Ariza; Akbari, Behzad; Cabrera, Alicia Triviño

    2013-01-01

    In recent years, Random Network Coding (RNC) has emerged as a promising solution for efficient Peer-to-Peer (P2P) video multicasting over the Internet. This probably refers to this fact that RNC noticeably increases the error resiliency and throughput of the network. However, high transmission overhead arising from sending large coefficients vector as header has been the most important challenge of the RNC. Moreover, due to employing the Gauss-Jordan elimination method, considerable computational complexity can be imposed on peers in decoding the encoded blocks and checking linear dependency among the coefficients vectors. In order to address these challenges, this study introduces MATIN which is a random network coding based framework for efficient P2P video streaming. The MATIN includes a novel coefficients matrix generation method so that there is no linear dependency in the generated coefficients matrix. Using the proposed framework, each peer encapsulates one instead of n coefficients entries into the generated encoded packet which results in very low transmission overhead. It is also possible to obtain the inverted coefficients matrix using a bit number of simple arithmetic operations. In this regard, peers sustain very low computational complexities. As a result, the MATIN permits random network coding to be more efficient in P2P video streaming systems. The results obtained from simulation using OMNET++ show that it substantially outperforms the RNC which uses the Gauss-Jordan elimination method by providing better video quality on peers in terms of the four important performance metrics including video distortion, dependency distortion, End-to-End delay and Initial Startup delay. PMID:23940530

  10. MATIN: a random network coding based framework for high quality peer-to-peer live video streaming.

    Directory of Open Access Journals (Sweden)

    Behrang Barekatain

    Full Text Available In recent years, Random Network Coding (RNC has emerged as a promising solution for efficient Peer-to-Peer (P2P video multicasting over the Internet. This probably refers to this fact that RNC noticeably increases the error resiliency and throughput of the network. However, high transmission overhead arising from sending large coefficients vector as header has been the most important challenge of the RNC. Moreover, due to employing the Gauss-Jordan elimination method, considerable computational complexity can be imposed on peers in decoding the encoded blocks and checking linear dependency among the coefficients vectors. In order to address these challenges, this study introduces MATIN which is a random network coding based framework for efficient P2P video streaming. The MATIN includes a novel coefficients matrix generation method so that there is no linear dependency in the generated coefficients matrix. Using the proposed framework, each peer encapsulates one instead of n coefficients entries into the generated encoded packet which results in very low transmission overhead. It is also possible to obtain the inverted coefficients matrix using a bit number of simple arithmetic operations. In this regard, peers sustain very low computational complexities. As a result, the MATIN permits random network coding to be more efficient in P2P video streaming systems. The results obtained from simulation using OMNET++ show that it substantially outperforms the RNC which uses the Gauss-Jordan elimination method by providing better video quality on peers in terms of the four important performance metrics including video distortion, dependency distortion, End-to-End delay and Initial Startup delay.

  11. Quality control in diagnostic mammography: myths, realities and their importance in the final image quality

    International Nuclear Information System (INIS)

    Mora Rodriguez, Patricia

    2011-01-01

    Mammography is the most used tool for early detection of breast cancer and reduce mortality from this cause. Studies with ionizing radiation it is important that be justified and provide a quality image to make the diagnosis, to get more benefits and fewer risks. The problem is the difficult to obtain an image of the breast. Therefore, the commitment to quality mammography is to maximize the contrast, definition, resolution and reliability, thus minimizing noise and dose. A mammogram performed without quality don't detect early breast cancer and the study doesn't have sense. Quality mammography requires trained and experienced staff, modern equipment and in good conditions, correct positioning, right technical factors and appropriate viewing conditions. In addition, quality programs are required to reach to ensure quality, control in testing techniques and image quality. (author) [es

  12. Quality control of conventional diagnostic radiology equipment in Serbia and Montenegro

    International Nuclear Information System (INIS)

    Ciraj, O.; Kosutic, D.; Markovic, S.

    2003-01-01

    There are more than 1500 diagnostic X-ray tubes in service in Serbia and Montenegro. Diagnostic X-ray equipment is checked on annual basis. X-ray equipment Qc protocols have been adopted from several international standards and guidelines [1,2], which have been modified according our practice and measuring equipment. According our inventory, about one half of all installed units is used for conventional X-ray diagnostics, 10% are mobile units, 2% of all in units in operation are mammographic devices an another 2% are computed tomography units. In addition there are about 600 dental X-ray units, which is 36% of all units. It is worth mentioning that almost 30 % of all installed units have single-phase generators, another 25% are tree phase (six and twelve pulse) generators and nearly 9% are high frequency units. Majority of units was installed more than 25 years ago. The Quality Control (QC) in radiography is a central part of QA programme, which deals with equipment maintenance and monitoring. QA in diagnostic radiology is a mean of maintaining standards in imaging and working towards minimizing patient and staff doses. As a part of QA programme in diagnostic radiology, the performance characteristics of 96 conventional X-ray units were measured in six months period during 2003. The diagnostic units were located in hospitals all over the country. They represent 25% of the total conventional diagnostic units of the country. About one half of measured X-ray units were new-installed. QC program has positive effect on X-ray equipment performance in a period of a few years. It is essential to perform QC tests for all installed X-ray units at least on annual basis. This would lead to production of consistent X-ray images, with minimal retake rate and hence, will contribute to decreasing of the patient dose. Patient doses are determined by multitude factors which interact in very complicated manner. It is very important to perform real patient dose measurements in

  13. Re-Establishment of Standard Radiation Qualities for Calibration of Dosemeter in Diagnostic Radiology - RQR Series

    International Nuclear Information System (INIS)

    Asmaliza Hashim; Norhayati Abdullah; Mohd Firdaus Abd Rahman

    2016-01-01

    After repairing the high voltage (HV) generator for Philips MG165 X-Ray Machine, the reestablishment of the standard radiation qualities has been done at Medical Physics Calibration Laboratory to meet the IEC and IAEA standard. Standard radiation qualities are the important criteria for calibration of dosemeter in diagnostic radiology. Standard radiation qualities are defined as the added filtration needed to produce and the half value layer (HVL) of the beam for specifies x-ray tube kilo voltage (kV). For calibration of dosemeter in diagnostic radiology, standard radiation qualities RQR represent the beam incident on the patient in general radiography, fluoroscopy and dental application. The HVL were measured using PTW ion chamber of volume 1 cm 3 with PTW electrometer and aluminium filter with 99.9 % purity was used as additional filter for RQR and filter for HVL. The first establishment of standard radiation qualities was made in 2009 for the radiation qualities of RQR. The results of additional filter and 1st HVL from 2009 to 2016 will be discussed further in paper. The ratios of the measured HVL to the standard IEC HVL value for the RQR series also described in this paper. The details of the measurement and the results are described in this paper. (author)

  14. Diagnostic mini-video assisted thoracic surgery. Effectiveness and accuracy of new generation 2.0 mm instruments.

    Science.gov (United States)

    Lazopoulos, G; Kotoulas, C; Kokotsakis, J; Foroulis, C; Lioulias, A

    2002-12-01

    Recently 2.0 mm mini-VATS has aroused much interest among surgeons involved with endoscopic surgery. We report our initial experience with the first first 54 patients who underwent this procedure. The aim of this study is to evaluate the effectiveness and accuracy of mini-VATS. 54 patients were undertaken to mini-VATS for diagnostic purposes. Patients were randomly selected and the indication for operation was set by the classic VATS criteria. 35 (65%) patients were treated under general anesthesia, while 19 (35%) patients were treated under local anesthesia. The average length of hospital stay was 1.8 +/- 0.9 days. The days of requirement for narcotic analgesia were 1.9 +/- 1.0. Diagnostic accuracy was 100%; morbidity and mortality rates were 0%. The high diagnostic accuracy and low operative danger, combined with less postoperative pain, due to minor surgical trauma and faster patient recovery, has established mini-VATS as a dynamic competitor to the classic VATS procedure. Since high technology is a strong partner in endoscopic surgery, a strong potentiality for evolution exists.

  15. Quality-of-Life Differences among Diagnostic Subgroups of Children Receiving Ventilating Tubes for Otitis Media.

    Science.gov (United States)

    Heidemann, Christian Hamilton; Lauridsen, Henrik Hein; Kjeldsen, Anette Drøhse; Faber, Christian Emil; Johansen, Eva Charlotte Jung; Godballe, Christian

    2015-10-01

    The pathological picture may differ considerably between diagnostic subgroups of children with otitis media receiving ventilating tubes. The aims of this study are to investigate differences in quality of life among diagnostic subgroups of children treated with ventilating tubes and to investigate possible predictors for clinical success. Longitudinal observational study. Secondary care units. Four hundred ninety-one families were enrolled in the study. The Otitis Media-6 questionnaire was applied in the assessment of child quality of life. Caregivers completed questionnaires at 7 time points from before treatment to 18-month follow-up. Logistic regression analysis was used to investigate possible predictors for clinical success. Response rates ranged from 96% to 81%; diagnostic distribution: 15% recurrent acute otitis media (rAOM), 47% otitis media with effusion (OME), and 38% mixed diagnosis of rAOM and OME (rAOM/OME). There were no significant differences between children diagnosed with rAOM and children diagnosed with rAOM/OME. However, these children had a significantly poorer quality of life at baseline compared with children diagnosed with only OME. Factors associated with clinical success included a diagnosis of rAOM, number of interrupted nights, physician visits, and canceled social activities due to OM. Results highlight the importance of distinguishing between diagnostic subgroups of children having ventilating tube treatment. A diagnosis of rAOM was found to predict baseline quality of life. Children with rAOM with or without OME were found to suffer significantly more than children with only OME before treatment. Factors associated with disease severity were found to predict clinical success. © American Academy of Otolaryngology-Head and Neck Surgery Foundation 2015.

  16. Quality assurance in diagnostic radiology in Hungary - first experiences in acceptance testing

    International Nuclear Information System (INIS)

    Porubszky, T.; Pellet, S.; Ballay, L.; Talian, L.; Giczi, F.

    2003-01-01

    It is a general experience that optimum imaging with minimum patient doses, moreover, the safe operation and long life of X-ray equipment can be assured by regular measurement of technical parameters and checking of their constancy (routine performance testing) only. These tests are generally known as quality control, while together with the so-called corrective actions and its management it is called (physical-technical) quality assurance (QA). In the European Union, Directive 97/43/EURATOM about radiation protection of patients requires - among others - the good practice of (physical-technical) quality assurance. In Hungary, Decree No. 31/2001. (X.3.) of the Minister of Health harmonizes all of its requirements. Acceptance testing of new diagnostic X-ray equipment is assigned to NPHC-NRIRR. QA has been a daily practice in radiation therapy and nuclear medicine for a long time. A National Patient Dose Assessment Programme has also successfully run since 1989. We had, however, only few preliminaries in QA in diagnostic radiology in the second half of the eighties. Nowadays there are running QA programmes in some hospitals and mammography centres. he testing activity of our institute is independent from manufacturers, it is run within the frame of an accredited testing laboratory, using calibrated measuring instruments and based on valid international standards. So the started way of implementing QA in diagnostic radiology needs a lot of further efforts, adapting experiences of other countries, and also some financial help to reach an acceptable level in the EU. (authors)

  17. Technique for verifying treatment fields using portal images with diagnostic quality.

    Science.gov (United States)

    Shiu, A S; Hogstrom, K R; Janjan, N A; Fields, R S; Peters, L J

    1987-10-01

    The image quality of portal films for megavoltage photon beams, when using the double-exposure technique, is poor compared to diagnostic quality, X ray images. A technique is described to record on a single film a megavoltage portal image superimposed upon a diagnostic X ray image, which provides the radiotherapist with "diagnostic quality" portal images. The technique uses a commercially available X ray tube mounted on the head of a 60Co unit. The alignment procedure, which uses a leveling device to ensure that the X ray focal spot and 60Co source are at the same location for each exposure, is confirmed by registering on film the image of an alignment marker. An evaluation of film-screen combination showed therapy verification film in a rare earth intensifying screen cassette to be best suited for this technique. The relationship between off-axis dose and the penumbral region of the portal image has been evaluated and should be useful in the interpretation of portal verification film relative to the treatment volume.

  18. Identifying Measures Used for Assessing Quality of YouTube Videos with Patient Health Information: A Review of Current Literature.

    Science.gov (United States)

    Gabarron, Elia; Fernandez-Luque, Luis; Armayones, Manuel; Lau, Annie Ys

    2013-02-28

    Recent publications on YouTube have advocated its potential for patient education. However, a reliable description of what could be considered quality information for patient education on YouTube is missing. To identify topics associated with the concept of quality information for patient education on YouTube in the scientific literature. A literature review was performed in MEDLINE, ISI Web of Knowledge, Scopus, and PsychINFO. Abstract selection was first conducted by two independent reviewers; discrepancies were discussed in a second abstract review with two additional independent reviewers. Full text of selected papers were analyzed looking for concepts, definitions, and topics used by its authors that focused on the quality of information on YouTube for patient education. In total, 456 abstracts were extracted and 13 papers meeting eligibility criteria were analyzed. Concepts identified related to quality of information for patient education are categorized as expert-driven, popularity-driven, or heuristic-driven measures. These include (in descending order): (1) quality of content in 10/13 (77%), (2) view count in 9/13 (69%), (3) health professional opinion in 8/13 (62%), (4) adequate length or duration in 6/13 (46%), (5) public ratings in 5/13 (39%), (6) adequate title, tags, and description in 5/13 (39%), (7) good description or a comprehensive narrative in 4/13 (31%), (8) evidence-based practices included in video in 4/13 (31%), (9) suitability as a teaching tool in 4/13 (31%), (10) technical quality in 4/13 (31%), (11) credentials provided in video in 4/13 (31%), (12) enough amount of content to identify its objective in 3/13 (23%), and (13) viewership share in 2/13 (15%). Our review confirms that the current topics linked to quality of information for patient education on YouTube are unclear and not standardized. Although expert-driven, popularity-driven, or heuristic-driven measures are used as proxies to estimate the quality of video information

  19. Delivering stable high-quality video: an SDN architecture with DASH assisting network elements

    NARCIS (Netherlands)

    J.W.M. Kleinrouweler (Jan Willem); S. Cabrero Barros (Sergio); P.S. Cesar Garcia (Pablo Santiago)

    2016-01-01

    textabstractDynamic adaptive streaming over HTTP (DASH) is a simple, but effective, technology for video streaming over the Internet. It provides adaptive streaming while being highly scalable at the side of the content providers. However, the mismatch between TCP and the adaptive bursty nature of

  20. Influence of plasma diagnostics and constraints on the quality of equilibrium reconstructions on Joint European Torus

    Energy Technology Data Exchange (ETDEWEB)

    Gelfusa, M.; Gaudio, P.; Peluso, E. [Associazione EURATOM-ENEA, University of Rome “Tor Vergata”, Roma (Italy); Murari, A.; Baruzzo, M. [Consorzio RFX-Associazione EURATOM ENEA per la Fusione, I-35127 Padova (Italy); Lupelli, I.; Hawkes, N.; Brix, M.; Drozdov, V.; Meigs, A.; Romanelli, M. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Craciunescu, T. [EURATOM-MEdC Association, NILPRP, Bucharest (Romania); Schmuck, S.; Sieglin, B. [Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald, EURATOM Association, Wendelsteinstr.1, 17491 Greifswald (Germany); Collaboration: JET-EFDA Contributors

    2013-10-15

    One of the main approaches to thermonuclear fusion relies on confining high temperature plasmas with properly shaped magnetic fields. The determination of the magnetic topology is, therefore, essential for controlling the experiments and for achieving the required performance. In Tokamaks, the reconstruction of the fields is typically formulated as a free boundary equilibrium problem, described by the Grad-Shafranov equation in toroidal geometry and axisymmetric configurations. Unfortunately, this results in mathematically very ill posed problems and, therefore, the quality of the equilibrium reconstructions depends sensitively on the measurements used as inputs and on the imposed constraints. In this paper, it is shown how the different diagnostics (Magnetics Measurements, Polarimetry and Motional Stark Effect), together with the edge current density and plasma pressure constraints, can have a significant impact on the quality of the equilibrium on JET. Results show that both the Polarimetry and Motional Stark Effect internal diagnostics are crucial in order to obtain reasonable safety factor profiles. The impact of the edge current density constraint is significant when the plasma is in the H-mode of confinement. In this plasma scenario the strike point positions and the plasma last closed flux surface can change even by centimetres, depending on the edge constraints, with a significant impact on the remapping of the equilibrium-dependent diagnostics and of pedestal physics studies. On the other hand and quite counter intuitively, the pressure constraint can severely affect the quality of the magnetic reconstructions in the core. These trends have been verified with several JET discharges and consistent results have been found. An interpretation of these results, as interplay between degrees of freedom and available measurements, is provided. The systematic analysis described in the paper emphasizes the importance of having sufficient diagnostic inputs and of

  1. Influence of plasma diagnostics and constraints on the quality of equilibrium reconstructions on Joint European Torus.

    Science.gov (United States)

    Gelfusa, M; Murari, A; Lupelli, I; Hawkes, N; Gaudio, P; Baruzzo, M; Brix, M; Craciunescu, T; Drozdov, V; Meigs, A; Peluso, E; Romanelli, M; Schmuck, S; Sieglin, B

    2013-10-01

    One of the main approaches to thermonuclear fusion relies on confining high temperature plasmas with properly shaped magnetic fields. The determination of the magnetic topology is, therefore, essential for controlling the experiments and for achieving the required performance. In Tokamaks, the reconstruction of the fields is typically formulated as a free boundary equilibrium problem, described by the Grad-Shafranov equation in toroidal geometry and axisymmetric configurations. Unfortunately, this results in mathematically very ill posed problems and, therefore, the quality of the equilibrium reconstructions depends sensitively on the measurements used as inputs and on the imposed constraints. In this paper, it is shown how the different diagnostics (Magnetics Measurements, Polarimetry and Motional Stark Effect), together with the edge current density and plasma pressure constraints, can have a significant impact on the quality of the equilibrium on JET. Results show that both the Polarimetry and Motional Stark Effect internal diagnostics are crucial in order to obtain reasonable safety factor profiles. The impact of the edge current density constraint is significant when the plasma is in the H-mode of confinement. In this plasma scenario the strike point positions and the plasma last closed flux surface can change even by centimetres, depending on the edge constraints, with a significant impact on the remapping of the equilibrium-dependent diagnostics and of pedestal physics studies. On the other hand and quite counter intuitively, the pressure constraint can severely affect the quality of the magnetic reconstructions in the core. These trends have been verified with several JET discharges and consistent results have been found. An interpretation of these results, as interplay between degrees of freedom and available measurements, is provided. The systematic analysis described in the paper emphasizes the importance of having sufficient diagnostic inputs and of

  2. Explanatory digital video disc with patients undergoing diagnostic cardiac catheterization Disco digital explicativo para pacientes sometidos al cateterismo cardiaco diagnóstico Digital video disc explicativo em pacientes submetidos ao cateterismo cardíaco diagnóstico

    Directory of Open Access Journals (Sweden)

    Sabrina Koehler Torrano

    2011-08-01

    Full Text Available The aim of this study was to evaluate knowledge of patients before outpatient diagnostic cardiac catheterization after viewing an explanatory Digital Video Disc, in a cardiology reference hospital. This cross-sectional study was carried out with patients undergoing their first cardiac catheterization and was performed from May to June 2009 in the hemodynamic sector. An instrument was used with questions (12 regarding the patients' understanding of the procedure. The intervention was a five-minute video prepared by the researchers. The sample was composed of 94 patients, divided into an intervention group (45 and a control group (49, with a mean age of 55±9 years and predominantly male. The patients of the IG had a higher rate of correct answers (74.6±17.1 compared to the CG (31.6±18.8, P=.000. The results demonstrated the efficacy of the presentation of a guidance video for patients undergoing a hemodynamic procedure.El objetivo de este estudio fue evaluar el conocimiento de los pacientes sometidos a cateterismo cardiaco tipo diagnóstico en ambulatorio después de ser presentado un DVD explicativo, en un hospital de referencia en cardiología. Se trata de un estudio transversal, con pacientes sometidos al primer cateterismo cardiaco, realizado de mayo a junio de 2009, en el sector de hemodinámica. Fue utilizado un instrumento con 12 preguntas referentes a la atención de los pacientes sobre el procedimiento. La intervención fue un vídeo con duración de cinco minutos elaborado por los investigadores. La muestra constituida de 94 pacientes, fue dividida en grupo intervención (45 y grupo control (49; la edad promedio fue de 55±9 años con predominancia del sexo masculino. Los pacientes del GI presentaron un mayor índice de aciertos (74,6±17,1, cuando comparados al GC (31,6±18,8, P=0,000. Los resultados demostraron la eficacia de la presentación de un vídeo de orientaciones para pacientes sometidos al procedimiento hemodin

  3. Quality control of diagnostic radiology to reduce absorbed dose of patients in Iran

    International Nuclear Information System (INIS)

    Aghahadi, Bahman.

    1996-01-01

    In order to reduce absorbed dose, to increase the image quality and to reduce the numbers of rejected films various quality control parameters were applied to X ray machines. These parameter are Kilo Volt peak, Milli Ampere, Exposure Time Focal Film Distance, Inherent Filters, Additional Filters Half Value Layer, Processor Condition, Cassettes. To evaluate and to apply these parameters in diagnostic radiological centers, ten hospitals were selected and a total number of 12 X ray machines were kept under quality control program. Considering different kinds of diagnostic radiology examination and to compare the dose before and after implementation of a quality control program, two kinds of examinations include in chest and abdomen examinations were considered. For each X ray machine, ten patients and for all selected centers, 120 patients were selected for chest examination and 120 patients for abdomen examinations; before and after implementation of quality control program, a total of 480 patients were selected randomly to be controlled. Base on different examinations carried out, it was concluded that both exposure conditions and general situations in radiological centers were not acceptable. The dosimetry results show that the average ski dose for chest and abdomen examinations were 0.28 m Gy and 4.23 Gy respectively. Before implementation of quality control step to reduce the surface skin dose, quality control parameters were applied and the exposure conditions were imposed. On average the absorbed doses for chest and abdomen examination were decreased to 79% and 61% respectively after the implementation of the program. From dose reduction point of view, the results of a part of this project which made by co-operation of International Atomic Energy Agency showed that Iran acquired the first grade for chest examination and second grade for abdomen examination. Base on the results obtained, the number of patients under chest and abdomen examination were 4041588 and

  4. Diagnostic laboratories in Asia Pacific region: Investigation on quality characteristics and time of reporting.

    Science.gov (United States)

    Badrick, Tony C; Gutscher, Anton; Sakamoto, Nakako; Chin, Daniel

    2017-07-01

    This is the result of a Survey of various aspects of quality, cost and speed in a large sample of diagnostic laboratories in the Asia Pacific region. It is the first of its type to be published and represents a snapshot of the current performance in a large number of diagnostic laboratories in a broad range of countries in the Asia Pacific region. This demonstrates that there are common issues facing all the laboratories surveyed but also common solutions using a Quality Systems approach which involves Accreditation, Customer responsiveness, greater use of IT, automation and Lean principles. The Survey provides data on some quality characteristics such as Turnaround Time (TAT) and quality improvement activities. It has been the case that some of the KPIs have improved over the course of the Surveys for example a reduction in the average TAT, and it might be that this occurred as a result of participation. Most laboratories have a target of 46-60min for STAT (Short Turnaround Time) on Clinical Chemistry and Immunoassay samples. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  5. Service quality of diagnostic fine needle aspiration cytology in a tertiary care hospital of lahore

    International Nuclear Information System (INIS)

    Rizvi, Z.; Usmani, R.A.; Zahra, T.; Rasool, H.; Rizvi, A.

    2017-01-01

    Quality of any service is the most important aspect for the manufacturer as well as the consumer. The primary objective of any nation's health system is to provide supreme quality health care services to its patients. The objective of this study was to assess the quality of diagnostic fine needle aspiration cytology service in a tertiary care hospital. As Patient's perspectives provide valuable information on quality of process, therefore, patient's perception in terms of satisfaction with the service was measured. Methods: In this cross sectional analytical study, 291 patients undergoing fine needle aspiration cytology in Mayo Hospital were selected by systematic sampling technique. Information regarding satisfaction of patients with four dimensions of service quality process, namely procedure, sterilization, conduct and competency of doctor was collected through interview on questionnaire. The questionnaire was developed on SERVQUAL model, a measurement tool, for quality assessment of services provided to patients. All items were assessed on 2- point likert scale (0=dissatisfied, 1=satisfied). Frequencies and percentages of satisfied and dissatisfied patients were recorded for each item and all items in each dimension were scored. If the percentage of sum of all item scores of a dimension was =60, the dimension was 'good quality'. Whereas <60% was 'poor quality' dimension. Data was analysed using epi-info-3.5.1. Fisher test was applied to check statistical significance. (p-value <0.05) Results: Out of the 4 dimensions of service quality process, Procedure (48.8%), Sterilization (51.5%) and practitioner conduct (50.9%) were perceived as 'poor' by the patients. Only practitioner competency (67.4%) was perceived as 'good'. Comparison of dimensions of service quality scoring with overall level of patient satisfaction revealed that all 4 dimensions were significantly related to patient dissatisfaction (p<.05

  6. Study about diagnostic quality in a public-center of mammography of Santa Fe, Argentina

    International Nuclear Information System (INIS)

    Lescano, R.; Kiguen, J.; Gaitan, L.; Caspani, C.

    2001-01-01

    The objective is to apply a method that allows us to evaluate the diagnostic quality of a public-center of mammography and to validate it. The representative centers of a social class were grouped; this one is evaluated measuring the mechanics, electrics, dosimetrics and personal parameters of the process to get the mammography diagnostic. The original study and the respective report was submitted to the valuation of a panel of experts, who evaluated image, techniques and diagnostics. The equipment and techniques used are described in this case. The judgment of the ACR and the Argentine legislation are applied. The dosimetric results of the mammography practice serve to determine the local reference levels. The people who intervened in the diagnosis are evaluated, as well as the services that can influence it. Seeking the parametric sensibility in relationship with the succeeded and precocious diagnosis, the success of it is confirmed by the panel of experts. We conclude by indicating that the success percentage in the diagnosis is about 98,36%, that there is 100% of coincidence among the perception and the value of the study quality. The valuation of the image reaches 69,2% of the maximum score, and the placement technique, 73,9%. The parametric sensibilities of the principal variables are discussed. (author)

  7. Statistical approach for optimization of external quality assurance (EQA) studies of molecular and serological viral diagnostics.

    Science.gov (United States)

    Rumer, Leonid; Domingo, Cristina; Donoso Mantke, Oliver; Dobrydneva, Yuliya; Greiner, Matthias; Niedrig, Matthias

    2016-10-01

    Management of viral diagnostic quality is based on external quality assurance (EQA), where laboratories involved in diagnostics of a targeted virus are offered to analyze a panel of blinded samples. The utility of EQAs is compromised because of the absence of an approach to EQA design which upfront defines acceptance criteria and associated statistical analysis ensuring fair and consistent interpretation. We offer a rigorous statistically based approach for EQA planning. Instead of a conventional performance characteristic (the score) which is calculated as the sum of the points for correctly identified samples in a blinded test panel, Youden index is used as the performance measure. Unlike the score, Youden index requires an estimate of sensitivity and specificity and incorporates the relationship of these performance parameters. Based on the assumption that the coordinator is a reputable expert of viral diagnostics, the performance of the coordinator's laboratory is defined as a proficiency standard for performance evaluation. The immediate goal of EQA is defined as to obtain a statistically reliable estimation for every laboratory whether its performance meets the proficiency standard, while the overall goal is to match every laboratory to its specific performance level. Dependence of informational capacities of test panel from the panel size and content is quantitatively analyzed and the optimal design and informational capacities of both idealized panels (whose size is not restricted by financial factors) and currently feasible panels are considered. Our approach provides the basis both for rational design of currently feasible EQA test panels and for an increased panel size.

  8. Architectures for radio over fiber transmission of high-quality video and data signals

    DEFF Research Database (Denmark)

    Lebedev, Alexander

    with a constraint on complexity. For wireless personal area networks distribution, we explore the notion of joint optimization of physical layer parameters of a fiber-wireless link (optical power levels, wireless transmission distance) and the codec parameters (quantization, error-resilience tools) based...... fiber in order to estimate the feasibility of mm-wave wireless video services’ delivery through fiber infrastructure with different nonlinear impairments and dispersion....

  9. External quality assessment of dengue and chikungunya diagnostics in the Asia Pacific region, 2015

    Science.gov (United States)

    Soh, Li Ting; Squires, Raynal C; Tan, Li Kiang; Pok, Kwoon Yong; Yang, HuiTing; Liew, Christina; Shah, Aparna Singh; Aaskov, John; Abubakar, Sazaly; Hasabe, Futoshi; Ng, Lee Ching

    2016-01-01

    Objective To conduct an external quality assessment (EQA) of dengue and chikungunya diagnostics among national-level public health laboratories in the Asia Pacific region following the first round of EQA for dengue diagnostics in 2013. Methods Twenty-four national-level public health laboratories performed routine diagnostic assays on a proficiency testing panel consisting of two modules. Module A contained serum samples spiked with cultured dengue virus (DENV) or chikungunya virus (CHIKV) for the detection of nucleic acid and DENV non-structural protein 1 (NS1) antigen. Module B contained human serum samples for the detection of anti-DENV antibodies. Results Among 20 laboratories testing Module A, 17 (85%) correctly detected DENV RNA by reverse transcription polymerase chain reaction (RT–PCR), 18 (90%) correctly determined serotype and 19 (95%) correctly identified CHIKV by RT–PCR. Ten of 15 (66.7%) laboratories performing NS1 antigen assays obtained the correct results. In Module B, 18/23 (78.3%) and 20/20 (100%) of laboratories correctly detected anti-DENV IgM and IgG, respectively. Detection of acute/recent DENV infection by both molecular (RT–PCR) and serological methods (IgM) was available in 19/24 (79.2%) participating laboratories. Discussion Accurate laboratory testing is a critical component of dengue and chikungunya surveillance and control. This second round of EQA reveals good proficiency in molecular and serological diagnostics of these diseases in the Asia Pacific region. Further comprehensive diagnostic testing, including testing for Zika virus, should comprise future iterations of the EQA. PMID:27508088

  10. External quality assessment of dengue and chikungunya diagnostics in the Asia Pacific region, 2015

    Directory of Open Access Journals (Sweden)

    Li Ting Soh

    2016-04-01

    Full Text Available Objective: To conduct an external quality assessment (EQA of dengue and chikungunya diagnostics among national-level public health laboratories in the Asia Pacific region following the first round of EQA for dengue diagnostics in 2013. Methods: Twenty-four national-level public health laboratories performed routine diagnostic assays on a proficiency testing panel consisting of two modules. Module A contained serum samples spiked with cultured dengue virus (DENV or chikungunya virus (CHIKV for the detection of nucleic acid and DENV non-structural protein 1 (NS1 antigen. Module B contained human serum samples for the detection of anti-DENV antibodies. Results: Among 20 laboratories testing Module A, 17 (85% correctly detected DENV RNA by reverse transcription polymerase chain reaction (RT-PCR, 18 (90% correctly determined serotype and 19 (95% correctly identified CHIKV by RT-PCR. Ten of 15 (66.7% laboratories performing NS1 antigen assays obtained the correct results. In Module B, 18/23 (78.3% and 20/20 (100% of laboratories correctly detected anti-DENV IgM and IgG, respectively. Detection of acute/recent DENV infection by both molecular (RT-PCR and serological methods (IgM was available in 19/24 (79.2% participating laboratories. Discussion: Accurate laboratory testing is a critical component of dengue and chikungunya surveillance and control. This second round of EQA reveals good proficiency in molecular and serological diagnostics of these diseases in the Asia Pacific region. Further comprehensive diagnostic testing, including testing for Zika virus, should comprise future iterations of the EQA.

  11. Algorithm for video summarization of bronchoscopy procedures.

    Science.gov (United States)

    Leszczuk, Mikołaj I; Duplaga, Mariusz

    2011-12-20

    The duration of bronchoscopy examinations varies considerably depending on the diagnostic and therapeutic procedures used. It can last more than 20 minutes if a complex diagnostic work-up is included. With wide access to videobronchoscopy, the whole procedure can be recorded as a video sequence. Common practice relies on an active attitude of the bronchoscopist who initiates the recording process and usually chooses to archive only selected views and sequences. However, it may be important to record the full bronchoscopy procedure as documentation when liability issues are at stake. Furthermore, an automatic recording of the whole procedure enables the bronchoscopist to focus solely on the performed procedures. Video recordings registered during bronchoscopies include a considerable number of frames of poor quality due to blurry or unfocused images. It seems that such frames are unavoidable due to the relatively tight endobronchial space, rapid movements of the respiratory tract due to breathing or coughing, and secretions which occur commonly in the bronchi, especially in patients suffering from pulmonary disorders. The use of recorded bronchoscopy video sequences for diagnostic, reference and educational purposes could be considerably extended with efficient, flexible summarization algorithms. Thus, the authors developed a prototype system to create shortcuts (called summaries or abstracts) of bronchoscopy video recordings. Such a system, based on models described in previously published papers, employs image analysis methods to exclude frames or sequences of limited diagnostic or education value. The algorithm for the selection or exclusion of specific frames or shots from video sequences recorded during bronchoscopy procedures is based on several criteria, including automatic detection of "non-informative", frames showing the branching of the airways and frames including pathological lesions. The paper focuses on the challenge of generating summaries of

  12. Algorithm for Video Summarization of Bronchoscopy Procedures

    Directory of Open Access Journals (Sweden)

    Leszczuk Mikołaj I

    2011-12-01

    Full Text Available Abstract Background The duration of bronchoscopy examinations varies considerably depending on the diagnostic and therapeutic procedures used. It can last more than 20 minutes if a complex diagnostic work-up is included. With wide access to videobronchoscopy, the whole procedure can be recorded as a video sequence. Common practice relies on an active attitude of the bronchoscopist who initiates the recording process and usually chooses to archive only selected views and sequences. However, it may be important to record the full bronchoscopy procedure as documentation when liability issues are at stake. Furthermore, an automatic recording of the whole procedure enables the bronchoscopist to focus solely on the performed procedures. Video recordings registered during bronchoscopies include a considerable number of frames of poor quality due to blurry or unfocused images. It seems that such frames are unavoidable due to the relatively tight endobronchial space, rapid movements of the respiratory tract due to breathing or coughing, and secretions which occur commonly in the bronchi, especially in patients suffering from pulmonary disorders. Methods The use of recorded bronchoscopy video sequences for diagnostic, reference and educational purposes could be considerably extended with efficient, flexible summarization algorithms. Thus, the authors developed a prototype system to create shortcuts (called summaries or abstracts of bronchoscopy video recordings. Such a system, based on models described in previously published papers, employs image analysis methods to exclude frames or sequences of limited diagnostic or education value. Results The algorithm for the selection or exclusion of specific frames or shots from video sequences recorded during bronchoscopy procedures is based on several criteria, including automatic detection of "non-informative", frames showing the branching of the airways and frames including pathological lesions. Conclusions

  13. The quality assurance program data analysis for diagnostic radiology in government hospitals in southern provinces of Syria

    International Nuclear Information System (INIS)

    Kharita, M. H.; Khedr, M. S.; Wannus, K. M.

    2008-01-01

    This study covered comprehensive evaluation for diagnostic radiography and fluorography equipment used in medicine by applying SAEC quality control rules. The results showed that most of considered x-ray equipment have an acceptable performance but few reached 21.6% in radiography and 36.8% in fluorography need repair and recalibration. Also recommendations and guidance for repair and preventative maintenance are required and quality assurance program should be applied in all diagnostic radiology institutions in Syria.(author)

  14. Quality initiatives: CT radiation dose reduction: how to implement change without sacrificing diagnostic quality.

    Science.gov (United States)

    Tamm, Eric P; Rong, X John; Cody, Dianna D; Ernst, Randy D; Fitzgerald, Nancy E; Kundra, Vikas

    2011-01-01

    The risks and benefits of using computed tomography (CT) as opposed to another imaging modality to accomplish a particular clinical goal should be weighed carefully. To accurately assess radiation risks and keep radiation doses as low as reasonably achievable, radiologists must be knowledgeable about the doses delivered during various types of CT studies performed at their institutions. The authors of this article propose a process improvement approach that includes the estimation of effective radiation dose levels, formulation of dose reduction goals, modification of acquisition protocols, assessment of effects on image quality, and implementation of changes necessary to ensure quality. A first step toward developing informed radiation dose reduction goals is to become familiar with the radiation dose values and radiation-associated health risks reported in the literature. Next, to determine the baseline dose values for a CT study at a particular institution, dose data can be collected from the CT scanners, interpreted, tabulated, and graphed. CT protocols can be modified to reduce overall effective dose by using techniques such as automated exposure control and iterative reconstruction, as well as by decreasing the number of scanning phases, increasing the section thickness, and adjusting the peak voltage (kVp setting), tube current-time product (milliampere-seconds), and pitch. Last, PDSA (plan, do, study, act) cycles can be established to detect and minimize negative effects of dose reduction methods on image quality.

  15. Everything is ok on YouTube! Quality assessment of YouTube videos on the topic of phacoemulsification in eyes with small pupil.

    Science.gov (United States)

    Aykut, Aslan; Kukner, Amber Senel; Karasu, Bugra; Palancıglu, Yeliz; Atmaca, Fatih; Aydogan, Tumay

    2018-01-22

    Usage of YouTube as an educational tool is gaining attention in academic research. To date, there has been no study on the content and quality of eye surgery videos on YouTube. The aim of this study was to analyze YouTube videos on phacoemulsification in eyes with small pupil. We searched for the phrases "small pupil cataract surgery," "small pupil phacoemulsification," "small pupil cataract surgery complications," and "small pupil phacoemulsification complications" in January 2015. Each resulting video was evaluated by all authors, and Krippendorff's alpha was calculated to measure agreement. Videos were classified according to pupil size (small/very small) in the beginning of the surgery, and whether pupillary diameter was large enough to continue surgery safely after pupillary dilation by the surgeon in the video (safe/not safe). Methods of dilatation were also analyzed. Any stated ocular comorbidity or surgical complications were noted. A total of 96 videos were reviewed. No mechanical intervention for pupillary dilatation was performed in 46 videos. Fifty-eight operated eyes had no stated ocular comorbidity. Ninety-five operations ended successfully without major complication. There was fair agreement between the evaluators regarding pupil sizes (Kα = 0.670) but poor agreement regarding safety (Kα = 0.337). YouTube videos on small pupil phacoemulsification have low complication rates when compared to the literature, although no reliable mechanical dilatation methods are used in almost half of these videos. Until YouTube's place in e-learning becomes clearer, we suggest that viewers be cautious regarding small pupil phacoemulsification videos on YouTube.

  16. A near infra-red video system as a protective diagnostic for electron cyclotron resonance heating operation in the Wendelstein 7-X stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Preynas, M.; Laqua, H. P.; Marsen, S.; Reintrog, A. [Max-Planck-Institut für Plasmaphysik (IPP), D-17491 Greifswald (Germany); Corre, Y.; Moncada, V.; Travere, J.-M. [IRFM, CEA-Cadarache, 13108 Saint Paul lez Durance Cedex (France)

    2015-11-15

    The Wendelstein 7-X stellarator is a large nuclear fusion device based at Max-Planck-Institut für Plasmaphysik in Greifswald in Germany. The main plasma heating system for steady state operation in W7-X is electron cyclotron resonance heating (ECRH). During operation, part of plama facing components will be directly heated by the non-absorbed power of 1 MW rf beams of ECRH. In order to avoid damages of such components made of graphite tiles during the first operational phase, a near infra-red video system has been developed as a protective diagnostic for safe and secure ECRH operation. Both the mechanical design housing the camera and the optical system are very flexible and respect the requirements of steady state operation. The full system including data acquisition and control system has been successfully tested in the vacuum vessel, including on-line visualization and data storage of the four cameras equipping the ECRH equatorial launchers of W7-X.

  17. A near infra-red video system as a protective diagnostic for electron cyclotron resonance heating operation in the Wendelstein 7-X stellarator

    Science.gov (United States)

    Preynas, M.; Laqua, H. P.; Marsen, S.; Reintrog, A.; Corre, Y.; Moncada, V.; Travere, J.-M.

    2015-11-01

    The Wendelstein 7-X stellarator is a large nuclear fusion device based at Max-Planck-Institut für Plasmaphysik in Greifswald in Germany. The main plasma heating system for steady state operation in W7-X is electron cyclotron resonance heating (ECRH). During operation, part of plama facing components will be directly heated by the non-absorbed power of 1 MW rf beams of ECRH. In order to avoid damages of such components made of graphite tiles during the first operational phase, a near infra-red video system has been developed as a protective diagnostic for safe and secure ECRH operation. Both the mechanical design housing the camera and the optical system are very flexible and respect the requirements of steady state operation. The full system including data acquisition and control system has been successfully tested in the vacuum vessel, including on-line visualization and data storage of the four cameras equipping the ECRH equatorial launchers of W7-X.

  18. A near infra-red video system as a protective diagnostic for electron cyclotron resonance heating operation in the Wendelstein 7-X stellarator.

    Science.gov (United States)

    Preynas, M; Laqua, H P; Marsen, S; Reintrog, A; Corre, Y; Moncada, V; Travere, J-M

    2015-11-01

    The Wendelstein 7-X stellarator is a large nuclear fusion device based at Max-Planck-Institut für Plasmaphysik in Greifswald in Germany. The main plasma heating system for steady state operation in W7-X is electron cyclotron resonance heating (ECRH). During operation, part of plama facing components will be directly heated by the non-absorbed power of 1 MW rf beams of ECRH. In order to avoid damages of such components made of graphite tiles during the first operational phase, a near infra-red video system has been developed as a protective diagnostic for safe and secure ECRH operation. Both the mechanical design housing the camera and the optical system are very flexible and respect the requirements of steady state operation. The full system including data acquisition and control system has been successfully tested in the vacuum vessel, including on-line visualization and data storage of the four cameras equipping the ECRH equatorial launchers of W7-X.

  19. Links between Autism Spectrum Disorder Diagnostic Status and Family Quality of Life

    Directory of Open Access Journals (Sweden)

    Andrew G. McKechanie

    2017-04-01

    Full Text Available Quality of life is often relatively lowered in families of children with additional needs, and this may be particularly the case where additional needs are accompanied by an autism spectrum disorder (ASD. Here we explore the effects of diagnostic status specifically, comparing families with children with an ASD diagnosis with others who a have additional needs but no signs of ASD; and b have additional needs and signs of ASD but no diagnosis. Mothers (n = 76 of children with additional needs completed standardised questionnaires about quality of life, stress, service provision, child behaviour and presence and severity of ASD traits. In addition, a group of mothers of typically developing young people (n = 17 completed standardised questionnaires on individual and family quality of life and on the behaviour of their son or daughter. Mothers of typically developing young people had significantly higher individual and family quality of life scores than each of the three other groups. Increased severity of ASD was associated with increased maternal stress, which in turn was associated with decreased family and maternal quality of life. The group reporting the lowest quality of life and the highest stress were the mothers of individuals with signs of ASD but no diagnosis. This pattern did not seem to be explained by lack of access to services, or rates of intellectual disability or challenging behaviour in this sub‐group. The finding that poor quality of life and high stress was most apparent in the sub‐group of mothers with children who had signs of ASD but did not have a diagnosis of ASD suggests that an interesting topic for further investigation is whether receipt of a diagnosis itself can positively influence quality of life and levels of maternal stress.

  20. Assessment of patient doses and image quality in X-ray diagnostics in Norway

    International Nuclear Information System (INIS)

    Olerud, H.M.

    1998-01-01

    Results from other industrialized countries indicate that the annual number of diagnostic procedures approaches one for every member of the population, and in many cases the individual radiation doses are higher than from any other human activity. Furthermore, the doses to patients for the same type of examination differ widely from place to place, suggesting that there is a considerable potential for dose reduction. This motivated an investigation of the diagnostic use of X-rays in Norway. The trends in the number of X-ray examinations performed annually have been studied. The patient doses (all diagnostics) and image quality (mammography and computed tomography) have been assessed for various radiological procedures. This form the basis for the assessment of total collective effective dose (CED) from X-rays in Norway, and further risk estimates. The radiological practice has then been evaluated according to the radiation protection principles of justification and optimisation. Based on the 1993 examination frequency, the total CED was assessed to 3400 manSv (0.78 mSv/inhabitant). It is estimated that this radiation burden may cause about 100 excess cancer deaths annually. The frequency of CT examination has doubled every fifth year, and did in 1993 represent 7% of the total number of examinations and 30% of the total CED. 129 refs

  1. Assessment of patient doses and image quality in X-ray diagnostics in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Olerud, H.M.

    1998-06-01

    Results from other industrialized countries indicate that the annual number of diagnostic procedures approaches one for every member of the population, and in many cases the individual radiation doses are higher than from any other human activity. Furthermore, the doses to patients for the same type of examination differ widely from place to place, suggesting that there is a considerable potential for dose reduction. This motivated an investigation of the diagnostic use of X-rays in Norway. The trends in the number of X-ray examinations performed annually have been studied. The patient doses (all diagnostics) and image quality (mammography and computed tomography) have been assessed for various radiological procedures. This form the basis for the assessment of total collective effective dose (CED) from X-rays in Norway, and further risk estimates. The radiological practice has then been evaluated according to the radiation protection principles of justification and optimisation. Based on the 1993 examination frequency, the total CED was assessed to 3400 manSv (0.78 mSv/inhabitant). It is estimated that this radiation burden may cause about 100 excess cancer deaths annually. The frequency of CT examination has doubled every fifth year, and did in 1993 represent 7% of the total number of examinations and 30% of the total CED. 129 refs.

  2. [Problems of the effective energy used as a quality expression of diagnostic X-ray].

    Science.gov (United States)

    Kato, Hideki; Hayashi, Naoki; Suzuki, Shoichi; Ando, Sho; Miyamoto, Mami; Wakasugi, Nao; Suzuki, Shizuma

    2011-01-01

    The effective energy has been generally used as a method of handily expressing an X-ray quality by one numerical value. The effective energy is a concept derived from "Half Value Layer (HVL)" that is the expressing parameter of beam quality based on the attenuation of the primary X-ray by a material. When beam quality is expressed by using HVL and / or the effective energy, it is necessary to describe the tube potential, the rectification method, and the homogeneity coefficient, etc. in parallel. However, recently feelings are that the effective energy should be handled like an absolute numerical value to physical characteristics of X-rays. In this paper, it was theoretically clarified that the effective energy had a different value depending on the absorber material used for the HVL measurement. In addition, the errors when physical characteristics of the X-rays were evaluated using the effective energy was also examined. Physical characteristics, such as interactions to the material of mono-energetic X-ray, are not equal to that of X-rays with a wide energy spectrum. It is not an easy comparison to express the quality of the diagnostic X-rays, and to calculate physical characteristics of the X-rays by using the effective energy. It is necessary to design a new method of expressing the quality of X-rays that takes the place of the "effective energy."

  3. A quality assurance study on the accuracy of measuring physical function under current conditions for use of clinical video telehealth.

    Science.gov (United States)

    Hoenig, Helen; Tate, Latoya; Dumbleton, Sarina; Montgomery, Christy; Morgan, Michelle; Landerman, Lawrence R; Caves, Kevin

    2013-05-01

    To determine whether conditions for use of clinical video telehealth technology might affect the accuracy of measures of physical function. Repeated measures. Veterans Administration Medical Center. Three healthy adult volunteers for a sample size of n=30 independent trials for each of 3 physical function tasks. None. Three tasks capturing differing aspects of physical function: fine-motor coordination (number of finger taps in 30s), gross-motor coordination (number of gait deviations in 10ft [3.05m]), and clinical spatial relations (identifying the proper height for a cane randomly preset ±0-2in [5.1cm] from optimal), with performance simultaneously assessed in person and video recorded. Interrater reliability and criterion validity were determined for the measurement of these 3 tasks scored according to 5 methods: (1) in person (community standard), (2) slow motion review of the video recording (criterion standard), and (3-5) full speed review at 3 Internet bandwidths (64kps, 384kps, and 768kps). Fine-motor coordination-Interrater reliability was variable (r=.43-.81) and criterion validity was poor at 64kps and 384kps, but both were acceptable at 768kps (reliability r=.74, validity β=.81). Gross-motor coordination-Interreliability was variable (range r=.53-.75) and criterion validity was poor at all bandwidths (β=.28-.47). Motionless spatial relations-Excellent reliability (r=.92-.97) and good criterion validity (β=.84-.89) at all the tested bandwidths. Internet bandwidth had differing effects on measurement validity and reliability for the fine-motor task, the gross-motor task, and spatial relations, with results for some tasks at some transmission speeds well below acceptable quality standards and community standards. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Does the Reporting Quality of Diagnostic Test Accuracy Studies, as Defined by STARD 2015, Affect Citation?

    Science.gov (United States)

    Choi, Young Jun; Chung, Mi Sun; Koo, Hyun Jung; Park, Ji Eun; Yoon, Hee Mang; Park, Seong Ho

    2016-01-01

    To determine the rate with which diagnostic test accuracy studies that are published in a general radiology journal adhere to the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015, and to explore the relationship between adherence rate and citation rate while avoiding confounding by journal factors. All eligible diagnostic test accuracy studies that were published in the Korean Journal of Radiology in 2011-2015 were identified. Five reviewers assessed each article for yes/no compliance with 27 of the 30 STARD 2015 checklist items (items 28, 29, and 30 were excluded). The total STARD score (number of fulfilled STARD items) was calculated. The score of the 15 STARD items that related directly to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 was also calculated. The number of times each article was cited (as indicated by the Web of Science) after publication until March 2016 and the article exposure time (time in months between publication and March 2016) were extracted. Sixty-three articles were analyzed. The mean (range) total and QUADAS-2-related STARD scores were 20.0 (14.5-25) and 11.4 (7-15), respectively. The mean citation number was 4 (0-21). Citation number did not associate significantly with either STARD score after accounting for exposure time (total score: correlation coefficient = 0.154, p = 0.232; QUADAS-2-related score: correlation coefficient = 0.143, p = 0.266). The degree of adherence to STARD 2015 was moderate for this journal, indicating that there is room for improvement. When adjusted for exposure time, the degree of adherence did not affect the citation rate.

  5. Dose the reporting quality of diagnostic test accuracy studies, as defined by STARD 2015, affect citation?

    International Nuclear Information System (INIS)

    Choi, Young Jun; Chung, Mi Sun; Koo, Hyun Jung; Park, Ji Eun; Yoon, Hee Mang; Park, Seong Ho

    2016-01-01

    To determine the rate with which diagnostic test accuracy studies that are published in a general radiology journal adhere to the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015, and to explore the relationship between adherence rate and citation rate while avoiding confounding by journal factors. All eligible diagnostic test accuracy studies that were published in the Korean Journal of Radiology in 2011–2015 were identified. Five reviewers assessed each article for yes/no compliance with 27 of the 30 STARD 2015 checklist items (items 28, 29, and 30 were excluded). The total STARD score (number of fulfilled STARD items) was calculated. The score of the 15 STARD items that related directly to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 was also calculated. The number of times each article was cited (as indicated by the Web of Science) after publication until March 2016 and the article exposure time (time in months between publication and March 2016) were extracted. Sixty-three articles were analyzed. The mean (range) total and QUADAS-2-related STARD scores were 20.0 (14.5–25) and 11.4 (7–15), respectively. The mean citation number was 4 (0–21). Citation number did not associate significantly with either STARD score after accounting for exposure time (total score: correlation coefficient = 0.154, p = 0.232; QUADAS-2-related score: correlation coefficient = 0.143, p = 0.266). The degree of adherence to STARD 2015 was moderate for this journal, indicating that there is room for improvement. When adjusted for exposure time, the degree of adherence did not affect the citation rate

  6. Temporal compounding: a novel implementation and its impact on quality and diagnostic value in echocardiography.

    Science.gov (United States)

    Perperidis, Antonios; Cusack, David; White, Audrey; McDicken, Norman; MacGillivray, Tom; Anderson, Tom

    2015-06-01

    Temporal compounding can be used to suppress acoustic noise in transthoracic cardiac ultrasound by spatially averaging partially decorrelated images acquired over consecutive cardiac cycles. However, the reliable spatial and temporal alignment of the corresponding frames in consecutive cardiac cycles is vital for effective implementation of temporal compounding. This study introduces a novel, efficient, accurate and robust technique for the spatiotemporal alignment of consecutive cardiac cycles with variable temporal characteristics. Furthermore, optimal acquisition parameters, such as the number of consecutive cardiac cycles used, are derived. The effect of the proposed implementation of temporal compounding on cardiac ultrasound images is quantitatively assessed (32 clinical data sets providing a representative range of image qualities and diagnostic values) using measures such as tissue signal-to-noise ratio, chamber signal-to-noise ratio, tissue/chamber contrast and detectability index, as well as a range of clinical measurements, such as chamber diameter and wall thickness, performed during routine echocardiographic examinations. Temporal compounding (as implemented) consistently improved the image quality and diagnostic value of the processed images, when compared with the original data by: (i) increasing tissue and cavity signal-to-noise ratios as well as tissue/cavity detectability index, (ii) improving the corresponding clinical measurement repeatability and inter-operator measurement agreement, while (iii) reducing the number of omitted measurements caused by data corruption. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Introduction of spirometry into clinical practice in Georgetown, Guyana: quality and diagnostic outcomes.

    Science.gov (United States)

    Johnston, J C; Rempel, C; Sanders, C; Piggott, E; Maxwell, Y; Jaipersaud, K; Luknauth, R; Persaud, D; Rambaran, M; Levy, R D

    2016-09-01

    Georgetown Public Hospital Corporation (GPHC), a 600-bed publicly funded referral hospital in Georgetown, Guyana. To assess spirometry quality and diagnostic outcomes 2 years after the introduction of spirometry into routine clinical practice at GPHC. We performed a retrospective review of 476 consecutive spirometry assessments performed from November 2013 to November 2015. We assessed the proportion and trend of spirometry tests meeting acceptability criteria, along with diagnostic interpretations and spirometry laboratory referral patterns. Overall, 80.4% of the 454 initial spirometry measurements on unique patients met the acceptability criteria, with no significant change in the proportion of acceptable spirometry over the study period (P = 0.450). Of the 369 (81.3%) first tests considered interpretable, 139 (30.6%) were normal, 151 (33.3%) were obstructive, 54 (11.9%) were suggestive of a restrictive pattern, 25 (5.5%) were suggestive of a mixed disorder and 119 (26.2%) tests met the definition of reversibility. Over a 2-year period, high-quality spirometry was performed in GPHC, a publicly funded hospital in a middle-income country with no pre-existing specialised respiratory service.

  8. Effects of orthodontic appliances on the diagnostic quality of magnetic resonance images of the head.

    Science.gov (United States)

    Zhylich, Dzmitry; Krishnan, Pradeep; Muthusami, Prakash; Rayner, Tammy; Shroff, Manohar; Doria, Andrea; Tompson, Bryan; Lou, Wendy; Suri, Sunjay

    2017-03-01

    The influence of 4 commonly used fixed orthodontic appliances on artifact formation and diagnostic quality of magnetic resonance (MR) images of the head produced by a 3-T MR scanner was studied. Stainless steel brackets, ceramic brackets, combination of ceramic brackets and steel molar tubes, and multistranded steel mandibular lingual retainers were embedded into custom-made trays for each of 10 adult subjects. Head MR scans of 9 regions were acquired for each subject wearing these trays. Sagittal T1-weighted, axial T2-weighted, axial gradient-recalled, axial diffusion-weighted, noncontrast axial MR angiography, and axial fluid-attenuated inversion recovery MR sequences were included. Two neuroradiologists evaluated image distortions and diagnostic qualities of the 1314 acquired images (13860 image slices). The images were affected by appliance, head region, and MR sequence. Stainless steel brackets and molar tubes affected the images the most, and ceramic brackets caused minimal image distortion. Head MR images are differentially affected by orthodontic appliances. The appliance, region imaged, and MR sequence should be considered before imaging patients wearing fixed orthodontic appliances. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  9. Traffic Analysis of Quality of Service (QoS for Video Conferencing between Main Campus and Sub Campus in Laboratory Scale

    Directory of Open Access Journals (Sweden)

    Amang Sudarsono

    2016-04-01

    Full Text Available Recently, in the distance learning system, video conferencing becomes one of expected course material delivery systems for creating a virtual class such that lecturer and student which are separated at long distance can engage a learning activity as well as face to face learning system. For this reason, the service availability and quality should be able to guaranteed and fulfilled. In this research, we analyze QoS of video conferencing between main campus and sub campus as the implementation of distance learning system in laboratory scale. Our experimental results show that the channel capacity or bandwidth of WAN connection between main campus and sub campus at 128 kbps is able to generate the throughput of video transmission and reception at 281 kbps and 24 kbps, respectively. Meanwhile, throughput of audio transmission and reception is 64 kbps and 26 kbps with the number of total packet loss for video and audio transmission is 84.3% and 29.2%, respectively. In this setting, the total jitter for video and audio transmission is 125 ms and 21 ms, respectively. In this case, there is no packet loss for traffic transmitting and receiving with jitter is not more than 5 ms. We also implemented QoS using Trust CoS model dan Trust DSCP for improving the quality of service in term of jitter up to 12.3% and 22.41%, respectively. Keywords: quality of service, throughput, delay, jitter, packet loss, Trust CoS, Trust DSCP

  10. Efficient data replication for the delivery of high-quality video content over P2P VoD advertising networks

    Science.gov (United States)

    Ho, Chien-Peng; Yu, Jen-Yu; Lee, Suh-Yin

    2011-12-01

    Recent advances in modern television systems have had profound consequences for the scalability, stability, and quality of transmitted digital data signals. This is of particular significance for peer-to-peer (P2P) video-on-demand (VoD) related platforms, faced with an immediate and growing demand for reliable service delivery. In response to demands for high-quality video, the key objectives in the construction of the proposed framework were user satisfaction with perceived video quality and the effective utilization of available resources on P2P VoD networks. This study developed a peer-based promoter to support online advertising in P2P VoD networks based on an estimation of video distortion prior to the replication of data stream chunks. The proposed technology enables the recovery of lost video using replicated stream chunks in real time. Load balance is achieved by adjusting the replication level of each candidate group according to the degree-of-distortion, thereby enabling a significant reduction in server load and increased scalability in the P2P VoD system. This approach also promotes the use of advertising as an efficient tool for commercial promotion. Results indicate that the proposed system efficiently satisfies the given fault tolerances.

  11. Development of a stable positive control to be used for quality assurance of rapid diagnostic tests for malaria

    NARCIS (Netherlands)

    Versteeg, Inge; Mens, Petra F.

    2009-01-01

    The objective of this study is to develop and evaluate a simple, cheap, and stable positive control for the quality control and quality assurance (QA) of rapid diagnostic tests (RDT) for the diagnosis of malaria. Plasmodium falciparum in vitro culture of known parasite concentrations was dried on a

  12. X ray spectra and qualities for use in diagnostic radiology and equipment calibration

    International Nuclear Information System (INIS)

    Souza, Karla Cristina de

    1996-12-01

    The goal of this work was the standardization of radiation qualities of diagnostic X ray equipment of the Assay Laboratory of the Institute for Radiation Protection and Dosimetry (IRD) of the National Commission of Nuclear Energy, Brazil. X ray spectra were determined from pulse height distribution measured directly on the primary beam using a high pure planar Ge detector. A program was developed to convert pulse height distribution into radiation spectra in the range from 20 to 150 keV. X ray qualities based on those used by the 'Physikalish-Technish Bundesantalt' (PTB) primary laboratory were implanted in three radiological equipment of the Assay Laboratory. These qualities simulate radiation beams on patients submitted to typical radiological examinations. Besides the spectrometric system, a reference measurement system based on an ionization chamber calibrated in air kerma was used to establish parameters such as kilovoltage, first and second half-value layer, mean energy, effective energy and inherent filtration. Our data have shown that the implantation of these radiation qualities in the Assay Laboratory results on a metrological basis for calibration of dose measurement assemblies and kV-meters, like those used by IRD to evaluate the parameters of X ray equipment around the country. A catalogue of spectral data resulting from this work is a data bank that allows various applications like dose calculation using Monte Carlo simulation techniques. (author)

  13. CD-ROM training course in quality assurance in diagnostic imaging

    International Nuclear Information System (INIS)

    Khoury, H.J.; Machado, P.; Drexler, G.

    2001-01-01

    This paper discusses the CD-ROM elaborated to provide a continuous professional formation and a practical guidance on the implementation and operation of routine quality assurance (QA) programme for medical physicists, regulator authorities and for those personnel concerned with the daily provision of diagnostic radiology services. The CD-ROM contains topics on the basic concepts of QA in radiodiagnostic, and it also allows the user to visualise effects on the variation of technical parameters (tube potential (kV) and current (mA), filtration) in the quality of the image. This possibility will contribute to the better understanding of the phenomena associated with the quality of the image. Besides, the program contains the procedures for the execution of the tests of the equipment and the route of implantation of program of quality assurance. It is interactive with the user, it fills a gap in the medical physics area and it allows the student's continuous formation because it assists the beginner, with the basic concepts, and the professional, with the aid in the implantation of the program of QA. The presentation is in the Portuguese language. (author)

  14. Extracting a Good Quality Frontal Face Image from a Low-Resolution Video Sequence

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Moeslund, Thomas B.

    2011-01-01

    Feeding low-resolution and low-quality images, from inexpensive surveillance cameras, to systems like, e.g., face recognition, produces erroneous and unstable results. Therefore, there is a need for a mechanism to bridge the gap between on one hand low-resolution and low-quality images and on the......Feeding low-resolution and low-quality images, from inexpensive surveillance cameras, to systems like, e.g., face recognition, produces erroneous and unstable results. Therefore, there is a need for a mechanism to bridge the gap between on one hand low-resolution and low-quality images...... and second is that its improvement factor is limited by a factor close to two. To deal with the first problem we introduce a three-step approach, which produces a face-log containing images of similar frontal faces of the highest possible quality. To deal with the second problem, limited improvement factor...

  15. Development of a Coding Instrument to Assess the Quality and Content of Anti-Tobacco Video Games.

    Science.gov (United States)

    Alber, Julia M; Watson, Anna M; Barnett, Tracey E; Mercado, Rebeccah; Bernhardt, Jay M

    2015-07-01

    Previous research has shown the use of electronic video games as an effective method for increasing content knowledge about the risks of drugs and alcohol use for adolescents. Although best practice suggests that theory, health communication strategies, and game appeal are important characteristics for developing games, no instruments are currently available to examine the quality and content of tobacco prevention and cessation electronic games. This study presents the systematic development of a coding instrument to measure the quality, use of theory, and health communication strategies of tobacco cessation and prevention electronic games. Using previous research and expert review, a content analysis coding instrument measuring 67 characteristics was developed with three overarching categories: type and quality of games, theory and approach, and type and format of messages. Two trained coders applied the instrument to 88 games on four platforms (personal computer, Nintendo DS, iPhone, and Android phone) to field test the instrument. Cohen's kappa for each item ranged from 0.66 to 1.00, with an average kappa value of 0.97. Future research can adapt this coding instrument to games addressing other health issues. In addition, the instrument questions can serve as a useful guide for evidence-based game development.

  16. Diagnostic ultrasound estimates of muscle mass and muscle quality discriminate between women with and without sarcopenia

    Directory of Open Access Journals (Sweden)

    Catheeja eIsmail

    2015-10-01

    Full Text Available Introduction: Age-related changes in muscle mass and muscle tissue composition contribute to diminished strength in older adults. The objectives of this study are to examine if an assessment method using mobile diagnostic ultrasound augments well-known determinants of lean body mass (LBM to aid sarcopenia staging, and if a sonographic measure of muscle quality is associated with muscle performance.Methods: Twenty community-dwelling female subjects participated in the study (age = 43.4 ±20.9 years; BMI: 23.8, interquartile range: 8.5. Dual energy X-ray absorptiometry (DXA and diagnostic ultrasound morphometry were used to estimate LBM. Muscle tissue quality was estimated via the echogenicity using grayscale histogram analysis. Peak force was measured with grip dynamometry and scaled for body size. Bivariate and multiple regression analyses were used to determine the association of the predictor variables with appendicular lean mass (aLM/ht2, and examine the relationship between scaled peak force values and muscle echogenicity. The sarcopenia LBM cut point value of 6.75 kg/m2 determined participant assignment into the Normal LBM and Low LBM subgroups.Results: The selected LBM predictor variables were body mass index (BMI, ultrasound morphometry, and age. Although BMI exhibited a significant positive relationship with aLM/ht2 (adj. R2 = .61, p < .001, the strength of association improved with the addition of ultrasound morphometry and age as predictor variables (adj. R2 = .85, p < .001. Scaled peak force was associated with age and echogenicity (adj. R2 = .53, p < .001, but not LBM. The Low LBM subgroup of women (n = 10 had higher scaled peak force, lower BMI, and lower echogenicity values in comparison to the Normal LBM subgroup (n = 10; p < .05.Conclusions: Diagnostic ultrasound morphometry values are associated with LBM, and improve the BMI predictive model for aLM/ht2 in women. In addition, ultrasound proxy measures of muscle quality are more

  17. Penicillin induced persistence in Chlamydia trachomatis: high quality time lapse video analysis of the developmental cycle.

    Directory of Open Access Journals (Sweden)

    Rachel J Skilton

    2009-11-01

    Full Text Available Chlamydia trachomatis is a major human pathogen with a unique obligate intracellular developmental cycle that takes place inside a modified cytoplasmic structure known as an inclusion. Following entry into a cell, the infectious elementary body (EB differentiates into a non-infectious replicative form known as a reticulate body (RB. RBs divide by binary fission and at the end of the cycle they redifferentiate into EBs. Treatment of C.trachomatis with penicillin prevents maturation of RBs which survive and enlarge to become aberrant RBs within the inclusion in a non-infective persistent state. Persistently infected individuals may be a reservoir for chlamydial infection. The C.trachomatis genome encodes the enzymes for peptidoglycan (PG biosynthesis but a PG sacculus has never been detected. This coupled to the action of penicillin is known as the chlamydial anomaly. We have applied video microscopy and quantitative DNA assays to the chlamydial developmental cycle to assess the effects of penicillin treatment and establish a framework for investigating penicillin induced chlamydial persistence.Addition of penicillin at the time of cell infection does not prevent uptake and the establishment of an inclusion. EB to RB transition occurs but bacterial cytokinesis is arrested by the second binary fission. RBs continue to enlarge but not divide in the presence of penicillin. The normal developmental cycle can be recovered by the removal of penicillin although the large, aberrant RBs do not revert to the normal smaller size but remain present to the completion of the developmental cycle. Chromosomal and plasmid DNA replication is unaffected by the addition of penicillin but the arrest of bacterial cytokinesis under these conditions results in RBs accumulating multiple copies of the genome.We have applied video time lapse microscopy to the study of the chlamydial developmental cycle. Linked with accurate measures of genome replication this provides a

  18. Video Compression Study: h.265 vs h.264

    Science.gov (United States)

    Pryor, Jonathan

    2016-01-01

    H.265 video compression (also known as High Efficiency Video Encoding (HEVC)) promises to provide double the video quality at half the bandwidth, or the same quality at half the bandwidth of h.264 video compression [1]. This study uses a Tektronix PQA500 to determine the video quality gains by using h.265 encoding. This study also compares two video encoders to see how different implementations of h.264 and h.265 impact video quality at various bandwidths.

  19. Radiological safety status and quality assurance audit of medical X-ray diagnostic installations in India

    Directory of Open Access Journals (Sweden)

    Sonawane A

    2010-01-01

    Full Text Available We conducted a radiological safety and quality assurance (QA audit of 118 medical X-ray diagnostic machines installed in 45 major hospitals in India. The main objective of the audit was to verify compliance with the regulatory requirements stipulated by the national regulatory body. The audit mainly covered accuracy check of accelerating potential (kVp, linearity of tube current (mA station and timer, congruence of radiation and optical field, and total filtration; in addition, we also reviewed medical X-ray diagnostic installations with reference to room layout of X-ray machines and conduct of radiological protection survey. A QA kit consisting of a kVp Test-O-Meter (ToM (Model RAD/FLU-9001, dose Test-O-Meter (ToM (Model 6001, ionization chamber-based radiation survey meter model Gun Monitor and other standard accessories were used for the required measurements. The important areas where there was noncompliance with the national safety code were: inaccuracy of kVp calibration (23%, lack of congruence of radiation and optical field (23%, nonlinearity of mA station (16% and timer (9%, improper collimator/diaphragm (19.6%, faulty adjustor knob for alignment of field size (4%, nonavailability of warning light (red light at the entrance of the X-ray room (29%, and use of mobile protective barriers without lead glass viewing window (14%. The present study on the radiological safety status of diagnostic X-ray installations may be a reasonably good representation of the situation in the country as a whole. The study contributes significantly to the improvement of radiological safety by the way of the steps already taken and by providing a vital feed back to the national regulatory body.

  20. Optimum image compression rate maintaining diagnostic image quality of digital intraoral radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ju Seop; Koh, Kwang Joon [Dept. of Oral and Maxillofacial Radiology and Institute of Oral Bio Science, School of Dentistry, Chonbuk National University, Chonju (Korea, Republic of)

    2000-12-15

    The aims of the present study are to determine the optimum compression rate in terms of file size reduction and diagnostic quality of the images after compression and evaluate the transmission speed of original or each compressed images. The material consisted of 24 extracted human premolars and molars. The occlusal surfaces and proximal surfaces of the teeth had a clinical disease spectrum that ranged from sound to varying degrees of fissure discoloration and cavitation. The images from Digora system were exported in TIFF and the images from conventional intraoral film were scanned and digitalized in TIFF by Nikon SF-200 scanner(Nikon, Japan). And six compression factors were chosen and applied on the basis of the results from a pilot study. The total number of images to be assessed were 336. Three radiologists assessed the occlusal and proximal surfaces of the teeth with 5-rank scale. Finally diagnosed as either sound or carious lesion by one expert oral pathologist. And sensitivity and specificity and kappa value for diagnostic agreement was calculated. Also the area (Az) values under the ROC curve were calculated and paired t-test and oneway ANOVA test was performed. Thereafter, transmission time of the image files of the each compression level were compared with that of the original image files. No significant difference was found between original and the corresponding images up to 7% (1:14) compression ratio for both the occlusal and proximal caries (p<0.05). JPEG3 (1:14) image files are transmitted fast more than 10 times, maintained diagnostic information in image, compared with original image files. 1:14 compressed image file may be used instead of the original image and reduce storage needs and transmission time.

  1. Quality control in diagnostic immunohistochemistry: integrated on-slide positive controls.

    Science.gov (United States)

    Bragoni, A; Gambella, A; Pigozzi, S; Grigolini, M; Fiocca, R; Mastracci, L; Grillo, F

    2017-11-01

    Standardization in immunohistochemistry is a priority in modern pathology and requires strict quality control. Cost containment has also become fundamental and auditing of all procedures must take into account both these principles. Positive controls must be routinely performed so that their positivity guarantees the appropriateness of the immunohistochemical procedure. The aim of this study is to develop a low cost (utilizing a punch biopsy-PB-tool) procedure to construct positive controls which can be integrated in the patient's tissue slide. Sixteen frequently used control blocks were selected and multiple cylindrical samples were obtained using a 5-mm diameter punch biopsy tool, separately re-embedding them in single blocks. For each diagnostic immunoreaction requiring a positive control, an integrated PB-control section (cut from the appropriate PB-control block) was added to the top right corner of the diagnostic slide before immunostaining. This integrated control technique permitted a saving of 4.75% in total direct lab costs and proved to be technically feasible and reliable. Our proposal is easy to perform and within the reach of all pathology labs, requires easily available tools, its application costs is less than using external paired controls and ensures that a specific control for each slide is always available.

  2. Quality control to the service of diagnostic radiology in policlinics and hospitals of Santiago de Cuba

    International Nuclear Information System (INIS)

    Grinnan Torres, Reinaldo; Parra Caboberde, Hector; Semanat Sanchez, Lino A.

    2002-01-01

    The work presents the results obtained in the Quality Control in diagnostic X-ray equipment accomplished in 33 clinics of Santiago de Cuba city. The performed test were, to the X-ray generator, X-ray tube, devices collimation and alignment, as well as to the light boxes, dark rooms, and radiographic screen-film combinations. Moreover the work presents the results of the Entrance Doses for a reference patient in radiographic projections of frequent use in clinics of Santiago de Cuba city (chest, lumbar spine, abdomen, and pelvis). For the evaluation of the verified technical parameters were used the tolerance criterions recommended by the Technical Guide elaborated by the State Control Centre of Medical of Cuba. In the case of the Entrance Dose were used the dose levels that recommended by the International Basic Safety Standards for protection against ionizing radiation and for safety of radiation sources

  3. Web-based tools for quality assurance and radiation protection in diagnostic radiology

    International Nuclear Information System (INIS)

    Moores, B. M.; Charnock, P.; Ward, M.

    2010-01-01

    Practical and philosophical aspects of radiation protection in diagnostic radiology have changed very little over the past 50 y even though patient doses have continued to rise significantly in this period. This rise has been driven by technological developments, such as multi-slice computed tomography, that have been able to improve diagnostic accuracy but not necessarily provide the same level of risk-benefit to all patients or groups of patients given the dose levels involved. Can practical radiation protection strategies hope to keep abreast of these ongoing developments? A project was started in 1992 in Liverpool that aimed to develop IT driven quality assurance (QA)/radiation protection software tools based upon a modular quality assurance dose data system. One of the modules involved the assessment of the patient entrance surface air kerma (ESAK) for an X-ray examination that was based upon the use of calibrated X-ray tube exposure factors to calculate ESAK as well as collecting appropriate patient details (age, sex, weight, thickness etc). The package also contained modules for logging all necessary equipment performance QA data. This paper will outline the experience gained with this system through its transition from a local application on a stand alone PC within the department to the current web-based approach. Advantages of a web-based approach to delivering such an application as well as centrally storing data originating on many hospital sites will be discussed together with the scientific support processes that can be developed with such a system. This will include local, national and international considerations. The advantages of importing radiographic examination details directly from other electronic storage systems such as a hospital's radiology information system will be presented together with practical outcomes already achieved. This will include the application of statistical techniques to the very large data sets generated. The development

  4. Objective assessment of the impact of frame rate on video quality

    DEFF Research Database (Denmark)

    Ukhanova, Ann; Korhonen, Jari; Forchhammer, Søren

    2012-01-01

    In this paper, we present a novel objective quality metric that takes the impact of frame rate into account. The proposed metric uses PSNR, frame rate and a content dependent parameter that can easily be obtained from spatial and temporal activity indices. The results have been validated on data...

  5. Hysteroscopy video summarization and browsing by estimating the physician's attention on video segments.

    Science.gov (United States)

    Gavião, Wilson; Scharcanski, Jacob; Frahm, Jan-Michael; Pollefeys, Marc

    2012-01-01

    Specialists often need to browse through libraries containing many diagnostic hysteroscopy videos searching for similar cases, or even to review the video of one particular case. Video searching and browsing can be used in many situations, like in case-based diagnosis when videos of previously diagnosed cases are compared, in case referrals, in reviewing the patient records, as well as for supporting medical research (e.g. in human reproduction). However, in terms of visual content, diagnostic hysteroscopy videos contain lots of information, but only a reduced number of frames are actually useful for diagnosis/prognosis purposes. In order to facilitate the browsing task, we propose in this paper a technique for estimating the clinical relevance of video segments in diagnostic hysteroscopies. Basically, the proposed technique associates clinical relevance with the attention attracted by a diagnostic hysteroscopy video segment during the video acquisition (i.e. during the diagnostic hysteroscopy conducted by a specialist). We show that the resulting video summary allows specialists to browse the video contents nonlinearly, while avoiding spending time on spurious visual information. In this work, we review state-of-art methods for summarizing general videos and how they apply to diagnostic hysteroscopy videos (considering their specific characteristics), and conclude that our proposed method contributes to the field with a summarization and representation method specific for video hysteroscopies. The experimental results indicate that our method tends to produce compact video summaries without discarding clinically relevant information. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. CEC quality criteria for diagnostic radiographic images and patient exposure trial

    International Nuclear Information System (INIS)

    Nahrstedt, U.; Wall, B.; Maccia, C.; Moores, B.M.; Padovani, R.

    1990-01-01

    The intention of this report has been to present the results of a multinational trial set up by a study group of the radiation protection programme of the CEC. In view of proceeding towards the harmonization and the optimization of the radiological techniques commonly used in different European countries, the relevance of quality criteria for radiographic images together with dose requirements were checked on about 900 examined patients. Due to the type of X-ray projections considered, more than 1 200 questionnaires concerning the real X-ray films were therefore collected and evaluated through a scoring system. Such an approach was relevant and contributed to providing practical considerations on how to reduce and optimize patient received dose while keeping the essential medical information imaged on the film. Indeed the results obtained allowed identification of technical modalities corresponding to that objective. Furthermore, analysis of results revealed two main areas which should be further taken into consideration: - personnel training in radiation protection (radiologists and radiographers), establishment of quality assurance programmes in diagnostic radiology (good usage of radiological equipment and reduction of wasted films)

  7. Dose management as a measurable criteria into the quality control programme of an imaging diagnostic clinic

    International Nuclear Information System (INIS)

    Kirova, G.; Georgiev, E.; Zasheva, C.; Georgiev, S.

    2014-01-01

    In the Radiology Department of Tokuda Hospital Sofia, a strong control over the radiation dose for all patients was accepted with the implementation of the Dose Watch software. The system allows bad practices to be discovered and improves the efficiency and quality of the CT procedures performed in the department. The article will briefly demonstrate the main steps, which have been done, and the results, which have been achieved. The purpose is to identify the challenges, the available tools, and the opportunities for improving the patients' dose in the CT sector of a general Radiology Department. Collected data was based on the information concerning the radiation dose absorbed by individual patients undergoing MDCT examinations in a general radiology department with an overall annual rate of around 7000 MDCT examinations. All of them were carried out using a single 64row MDCT system. The hospital logbook was used to identify the number of CT examinations and dose levels associated with some typical diagnostic procedures in order to make an analysis. The information was taken form the PACS and Dose Watch software and was analyzed. The article draws some measures towards improving the organization and reducing the dose, keeping the quality of the performed exams. Thanks to the supportive software for dose tracking, analyzing and reporting, some problems have been solved and some reasonable measures have been implemented into the daily practice. (authors) Key words: RADIATION DOSE. MDCT. DOSE REDUCTION. REFERRAL GUIDELINES.CTDI. DLP

  8. Mandatory quality assurance programmes for diagnostic radiology facilities in Ontario, Canada

    International Nuclear Information System (INIS)

    Rainbow, A.J.

    1989-01-01

    Regulations made under the Healing Arts Radiation Protection (HARP) Act, Government of Ontario, Canada, were promulgated in the form of a safety Code in November, 1985. These regulations require a minimum technical quality assurance (QA) programme for all diagnostic radiology facilities in the Province. The mandatory QA programme requires certain tests and procedures to be carried out at specified intervals. The tests include photographic quality control, patient entrance exposure measurement, collimation, half-value layer, phototiming parameters, fluoroscopic parameters including maximum patient entrance exposure rate, resolution, limit timer and automatic brightness control, and tomographic parameters including fulcrum accuracy, thickness of cut and mechanical stability. Records of the results of these tests must be kept for at least 6 years. A set of HARP guidelines published in June 1987 includes a description of appropriate measuring methods for each test together with a set of forms for recording the results of such tests. The regulations specify limiting values for a number of equipment performance parameters, including the maximum allowable patient skin entrance exposure values for common radiographic projections. (author)

  9. Radiation exposure and image quality in X-ray diagnostic radiology. Physical principles and clinical applications. 2. ed.

    International Nuclear Information System (INIS)

    Saebel, Manfred; Aichinger, Horst; Dierker, Joachim; Joite-Barfuss, Sigrid

    2012-01-01

    Diagnostic X-rays are the largest contributor to radiation exposure to the general population, and protecting the patient from radiation damage is a major aim of modern health policy. Once the decision has been taken to use ionising radiation for imaging in a particular patient, it is necessary to optimize the image acquisition process taking into account the diagnostic quality of the images and the radiation dose to the patient. Both image quality and radiation dose are affected by a number of parameters, knowledge of which permits scientifically based decision making. The authors of this second edition of Radiation Exposure and Image Quality in X-ray Diagnostic Radiology have spent many years studying the optimization of radiological imaging. In this book they present in detail the basic physical principles of diagnostic radiology and their application to clinical problems. Particular attention is devoted to evaluation of the dose to the patient, the influence of scattered radiation on image quality, the use of antiscatter grids, and optimization of image quality and dose. The final section is a supplement containing tables of data and graphical depictions of X-ray spectra, interaction coefficients, characteristics of X-ray beams, and other aspects relevant to patient dose calculations. In addition, a complementary CD-ROM contains a user-friendly Excel file database covering these aspects that can be used in the reader's own programs. Since the first edition, the text, figures, tables, and references have all been thoroughly updated, and more detailed attention is now paid to image quality and radiation exposure when using digital imaging and computed tomography. This book will be an invaluable aid to medical physicists when performing calculations relating to patient dose and image quality, and will also prove useful for diagnostic radiologists and engineers. (orig.)

  10. Quality control of pediatric chest X-rays in diagnostic centers with and without pediatric competence

    International Nuclear Information System (INIS)

    Alt, C.D.; Engelmann, D.; Schenk, J.P.; Troeger, J.

    2006-01-01

    Purpose: Radiation protection in pediatric radiology is very important because of the particular sensitivity of radiosensitive organs in younger patients. Optimized image quality supports radiation protection and should be targeted. In our study we examined the quality of pediatric chest X-rays at diagnostic centers (university hospitals and other large clinics). We then evaluated differences in image quality in departments without pediatric competence (R) and departments with pediatric competence (PR). Materials and Methods: Our study was based on 313 conventional chest X-rays from 207 patients (192 p.a./a.p. and 121 lateral, 43 from R, 258 from PR and 12 neither from R nor KR) and 38 digital chest X-rays from 26 patients (25 p.a./a.p. and 13 lateral, 1 from R and 37 from PR). All patients (age 0 - 18 years) are from Nephroblastoma-Study SIOP-93/01-GPOH. We examined all initial chest X-rays, which were sent to us for evaluation upon request between 4/3/2002 and 6/14/2002. The examined parameters were: exposure, centering of the X-rays/patient positioning, collimation and sharpness. The X-rays were evaluated on a scale from 1 (best result) to 5 (worst result), resulting in an overall score of A = optimum, B = minor problems, C = major problems, or D = unusable. The optical density, the center of the image and the relative field size were also measured. Statistical tests (Mann-Whitney-U and log regression) were carried out on the conventional images. The study was performed retrospectively. The exposure, sharpness and optical density of the digital X-rays were not analyzed. Results: In the case of all conventional X-rays, the quality of the centering of the X-rays/patient positioning and collimation was moderate (average scale value: 2.4 and 2.8), and the quality of the exposure and sharpness was good and very good (average scale value: 1.9 and 1.5). The quality of the chest X-rays in departments with additional pediatric radiological expertise was better mainly in

  11. Sound for digital video

    CERN Document Server

    Holman, Tomlinson

    2013-01-01

    Achieve professional quality sound on a limited budget! Harness all new, Hollywood style audio techniques to bring your independent film and video productions to the next level.In Sound for Digital Video, Second Edition industry experts Tomlinson Holman and Arthur Baum give you the tools and knowledge to apply recent advances in audio capture, video recording, editing workflow, and mixing to your own film or video with stunning results. This fresh edition is chockfull of techniques, tricks, and workflow secrets that you can apply to your own projects from preproduction

  12. Evaluation of QUADAS, a tool for the quality assessment of diagnostic accuracy studies

    Directory of Open Access Journals (Sweden)

    Bossuyt Patrick NM

    2006-03-01

    Full Text Available Abstract Background A quality assessment tool for diagnostic accuracy studies, named QUADAS, has recently been developed. Although QUADAS has been used in several systematic reviews, it has not been formally validated. The objective was to evaluate the validity and usefulness of QUADAS. Methods Three reviewers independently rated the quality of 30 studies using QUADAS. We assessed the proportion of agreements between each reviewer and the final consensus rating. This was done for all QUADAS items combined and for each individual item. Twenty reviewers who had used QUADAS in their reviews completed a short structured questionnaire on their experience of QUADAS. Results Over all items, the agreements between each reviewer and the final consensus rating were 91%, 90% and 85%. The results for individual QUADAS items varied between 50% and 100% with a median value of 90%. Items related to uninterpretable test results and withdrawals led to the most disagreements. The feedback on the content of the tool was generally positive with only small numbers of reviewers reporting problems with coverage, ease of use, clarity of instructions and validity. Conclusion Major modifications to the content of QUADAS itself are not necessary. The evaluation highlighted particular difficulties in scoring the items on uninterpretable results and withdrawals. Revised guidelines for scoring these items are proposed. It is essential that reviewers tailor guidelines for scoring items to their review, and ensure that all reviewers are clear on how to score studies. Reviewers should consider whether all QUADAS items are relevant to their review, and whether additional quality items should be assessed as part of their review.

  13. Application of Quality Assurance Strategies in Diagnostics and Clinical Support Services in Iranian Hospitals

    Directory of Open Access Journals (Sweden)

    Asgar Aghaei Hashjin

    2015-10-01

    Full Text Available Background Iran has a widespread diagnostics and clinical support services (DCSS network that plays a crucial role in providing diagnostic and clinical support services to both inpatient and outpatient care. However, very little is known on the application of quality assurance (QA policies in DCSS units. This study explores the extent of application of eleven QA strategies in DCSS units within Iranian hospitals and its association with hospital characteristics. Methods A descriptive cross-sectional study was conducted in 2009/2010. Data were collected from 554 DCSS units among 84 hospitals. Results The average reported application rate for the QA strategies ranged from 57%-94% in the DCSS units. Most frequently reported were checking drugs expiration dates (94%, pharmacopoeia availability (92%, equipment calibration (87% and identifying responsibilities (86%. Least reported was external auditing of the DCSS (57%. The clinical chemistry and microbiology laboratories (84%, pharmacies, blood bank services (83% reported highest average application rates across all questioned QA strategies. Lowest application rates were reported in human tissue banks (50%. There was no significant difference between the reported application rates in DCSS in the general/specialized, teaching/research, nonteaching/research hospitals with the exception of pharmacies and radiology departments. They reported availability of a written QA plan significantly more often in research hospitals. Nearly all QA strategies were reported to be applied significantly more often in the DCSS of Social Security Organization (SSO and private-for-profit hospitals than in governmental hospitals. Conclusion There is still room for strengthening the managerial cycle of QA systems and accountability in the DCSS in Iranian hospitals. Getting feedback, change and learning through application of specific QA strategies (eg, external/internal audits can be improved. Both the effectiveness of QA

  14. Application of Quality Assurance Strategies in Diagnostics and Clinical Support Services in Iranian Hospitals.

    Science.gov (United States)

    Aghaei Hashjin, Asgar; Kringos, Dionne; Ravaghi, Hamid; Manoochehri, Jila; Gorji, Hassan Abolghasem; Klazinga, Niek S

    2015-05-20

    Iran has a widespread diagnostics and clinical support services (DCSS) network that plays a crucial role in providing diagnostic and clinical support services to both inpatient and outpatient care. However, very little is known on the application of quality assurance (QA) policies in DCSS units. This study explores the extent of application of eleven QA strategies in DCSS units within Iranian hospitals and its association with hospital characteristics. A descriptive cross-sectional study was conducted in 2009/2010. Data were collected from 554 DCSS units among 84 hospitals. The average reported application rate for the QA strategies ranged from 57%-94% in the DCSS units. Most frequently reported were checking drugs expiration dates (94%), pharmacopoeia availability (92%), equipment calibration (87%) and identifying responsibilities (86%). Least reported was external auditing of the DCSS (57%). The clinical chemistry and microbiology laboratories (84%), pharmacies, blood bank services (83%) reported highest average application rates across all questioned QA strategies. Lowest application rates were reported in human tissue banks (50%). There was no significant difference between the reported application rates in DCSS in the general/specialized, teaching/research, nonteaching/research hospitals with the exception of pharmacies and radiology departments. They reported availability of a written QA plan significantly more often in research hospitals. Nearly all QA strategies were reported to be applied significantly more often in the DCSS of Social Security Organization (SSO) and private-for-profit hospitals than in governmental hospitals. There is still room for strengthening the managerial cycle of QA systems and accountability in the DCSS in Iranian hospitals. Getting feedback, change and learning through application of specific QA strategies (eg, external/internal audits) can be improved. Both the effectiveness of QA strategies in practice, and the application of

  15. Application of Quality Assurance Strategies in Diagnostics and Clinical Support Services in Iranian Hospitals

    Science.gov (United States)

    Aghaei Hashjin, Asgar; Kringos, Dionne; Ravaghi, Hamid; Manoochehri, Jila; Gorji, Hassan Abolghasem; Klazinga, Niek S.

    2015-01-01

    Background: Iran has a widespread diagnostics and clinical support services (DCSS) network that plays a crucial role in providing diagnostic and clinical support services to both inpatient and outpatient care. However, very little is known on the application of quality assurance (QA) policies in DCSS units. This study explores the extent of application of eleven QA strategies in DCSS units within Iranian hospitals and its association with hospital characteristics. Methods: A descriptive cross-sectional study was conducted in 2009/2010. Data were collected from 554 DCSS units among 84 hospitals. Results: The average reported application rate for the QA strategies ranged from 57%-94% in the DCSS units. Most frequently reported were checking drugs expiration dates (94%), pharmacopoeia availability (92%), equipment calibration (87%) and identifying responsibilities (86%). Least reported was external auditing of the DCSS (57%). The clinical chemistry and microbiology laboratories (84%), pharmacies, blood bank services (83%) reported highest average application rates across all questioned QA strategies. Lowest application rates were reported in human tissue banks (50%). There was no significant difference between the reported application rates in DCSS in the general/specialized, teaching/research, nonteaching/research hospitals with the exception of pharmacies and radiology departments. They reported availability of a written QA plan significantly more often in research hospitals. Nearly all QA strategies were reported to be applied significantly more often in the DCSS of Social Security Organization (SSO) and private-for-profit hospitals than in governmental hospitals. Conclusion: There is still room for strengthening the managerial cycle of QA systems and accountability in the DCSS in Iranian hospitals. Getting feedback, change and learning through application of specific QA strategies (eg, external/internal audits) can be improved. Both the effectiveness of QA

  16. Limits of the possible: diagnostic image quality in coronary angiography with third-generation dual-source CT.

    Science.gov (United States)

    Ochs, Marco M; Siepen, Fabian Aus dem; Fritz, Thomas; Andre, Florian; Gitsioudis, Gitsios; Korosoglou, Grigorios; Seitz, Sebastian; Bogomazov, Yuriy; Schlett, Christopher L; Sokiranski, Roman; Sommer, Andre; Gückel, Friedemann; Brado, Matthias; Kauczor, Hans-Ulrich; Görich, Johannes; Friedrich, Matthias G W; Katus, Hugo A; Buss, Sebastian J

    2017-07-01

    The usage of coronary CT angiography (CTA) is appropriate in patients with acute or chronic chest pain; however the diagnostic accuracy may be challenged with increased Agatston score (AS), increased heart rate, arrhythmia and severe obesity. Thus, we aim to determine the potential of the recently introduced third-generation dual-source CT (DSCT) for CTA in a 'real-life' clinical setting. Two hundred and sixty-eight consecutive patients (age: 67 ± 10 years; BMI: 27 ± 5 kg/m²; 61% male) undergoing clinically indicated CTA with DSCT were included in the retrospective single-center analysis. A contrast-enhanced volume dataset was acquired in sequential (SSM) (n = 151) or helical scan mode (HSM) (n = 117). Coronary segments were classified in diagnostic or non-diagnostic image quality. A subset underwent invasive angiography to determine the diagnostic accuracy of CTA. SSM (96.8 ± 6%) and HSM (97.5 ± 8%) provided no significant differences in the overall diagnostic image quality. However, AS had significant influence on diagnostic image quality exclusively in SSM (B = 0.003; p = 0.0001), but not in HSM. Diagnostic image quality significantly decreased in SSM in patients with AS ≥2,000 (p = 0.03). SSM (sensitivity: 93.9%; specificity: 96.7%; PPV: 88.6%; NPV: 98.3%) and HSM (sensitivity: 97.4%; specificity: 94.3%; PPV: 86.0%; NPV: 99.0%) provided comparable diagnostic accuracy (p = n.s.). SSM yielded significantly lower radiation doses as compared to HSM (2.1 ± 2.0 vs. 5.1 ± 3.3 mSv; p = 0.0001) in age and BMI-matched cohorts. SSM in third-generation DSCT enables significant dose savings and provides robust diagnostic image quality in patients with AS ≤2000 independent of heart rate, heart rhythm or obesity.

  17. Diagnostic accuracy of refractometry for assessing bovine colostrum quality: A systematic review and meta-analysis.

    Science.gov (United States)

    Buczinski, S; Vandeweerd, J M

    2016-09-01

    Provision of good quality colostrum [i.e., immunoglobulin G (IgG) concentration ≥50g/L] is the first step toward ensuring proper passive transfer of immunity for young calves. Precise quantification of colostrum IgG levels cannot be easily performed on the farm. Assessment of the refractive index using a Brix scale with a refractometer has been described as being highly correlated with IgG concentration in colostrum. The aim of this study was to perform a systematic review of the diagnostic accuracy of Brix refractometry to diagnose good quality colostrum. From 101 references initially obtain ed, 11 were included in the systematic review meta-analysis representing 4,251 colostrum samples. The prevalence of good colostrum samples with IgG ≥50g/L varied from 67.3 to 92.3% (median 77.9%). Specific estimates of accuracy [sensitivity (Se) and specificity (Sp)] were obtained for different reported cut-points using a hierarchical summary receiver operating characteristic curve model. For the cut-point of 22% (n=8 studies), Se=80.2% (95% CI: 71.1-87.0%) and Sp=82.6% (71.4-90.0%). Decreasing the cut-point to 18% increased Se [96.1% (91.8-98.2%)] and decreased Sp [54.5% (26.9-79.6%)]. Modeling the effect of these Brix accuracy estimates using a stochastic simulation and Bayes theorem showed that a positive result with the 22% Brix cut-point can be used to diagnose good quality colostrum (posttest probability of a good colostrum: 94.3% (90.7-96.9%). The posttest probability of good colostrum with a Brix value <18% was only 22.7% (12.3-39.2%). Based on this study, the 2 cut-points could be alternatively used to select good quality colostrum (sample with Brix ≥22%) or to discard poor quality colostrum (sample with Brix <18%). When sample results are between these 2 values, colostrum supplementation should be considered. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  18. Air quality modeling for accountability research: Operational, dynamic, and diagnostic evaluation

    Science.gov (United States)

    Henneman, Lucas R. F.; Liu, Cong; Hu, Yongtao; Mulholland, James A.; Russell, Armistead G.

    2017-10-01

    Photochemical grid models play a central role in air quality regulatory frameworks, including in air pollution accountability research, which seeks to demonstrate the extent to which regulations causally impacted emissions, air quality, and public health. There is a need, however, to develop and demonstrate appropriate practices for model application and evaluation in an accountability framework. We employ a combination of traditional and novel evaluation techniques to assess four years (2001-02, 2011-12) of simulated pollutant concentrations across a decade of major emissions reductions using the Community Multiscale Air Quality (CMAQ) model. We have grouped our assessments in three categories: Operational evaluation investigates how well CMAQ captures absolute concentrations; dynamic evaluation investigates how well CMAQ captures changes in concentrations across the decade of changing emissions; diagnostic evaluation investigates how CMAQ attributes variability in concentrations and sensitivities to emissions between meteorology and emissions, and how well this attribution compares to empirical statistical models. In this application, CMAQ captures O3 and PM2.5 concentrations and change over the decade in the Eastern United States similarly to past CMAQ applications and in line with model evaluation guidance; however, some PM2.5 species-EC, OC, and sulfate in particular-exhibit high biases in various months. CMAQ-simulated PM2.5 has a high bias in winter months and low bias in the summer, mainly due to a high bias in OC during the cold months and low bias in OC and sulfate during the summer. Simulated O3 and PM2.5 changes across the decade have normalized mean bias of less than 2.5% and 17%, respectively. Detailed comparisons suggest biased EC emissions, negative wintertime SO42- sensitivities to mobile source emissions, and incomplete capture of OC chemistry in the summer and winter. Photochemical grid model-simulated O3 and PM2.5 responses to emissions and

  19. A new multimodal interactive way of subjective scoring of 3D video quality of experience

    Science.gov (United States)

    Kim, Taewan; Lee, Kwanghyun; Lee, Sanghoon; Bovik, Alan C.

    2014-03-01

    People that watch today's 3D visual programs, such as 3D cinema, 3D TV and 3D games, experience wide and dynamically varying ranges of 3D visual immersion and 3D quality of experience (QoE). It is necessary to be able to deploy reliable methodologies that measure each viewers subjective experience. We propose a new methodology that we call Multimodal Interactive Continuous Scoring of Quality (MICSQ). MICSQ is composed of a device interaction process between the 3D display and a separate device (PC, tablet, etc.) used as an assessment tool, and a human interaction process between the subject(s) and the device. The scoring process is multimodal, using aural and tactile cues to help engage and focus the subject(s) on their tasks. Moreover, the wireless device interaction process makes it possible for multiple subjects to assess 3D QoE simultaneously in a large space such as a movie theater, and at di®erent visual angles and distances.

  20. Diagnostics of Track Quality of Ballastless Track and Transition Areas in Vicinity of Portals of Tunnel Turecky vrch

    Directory of Open Access Journals (Sweden)

    Šmalo Michal

    2016-05-01

    Full Text Available The paper deals with the partial results of diagnostics of experimental sections of ballastless track Rheda 2000® and transition areas between ballastless and ballasted track structure around portals of tunnel Turecky vrch after six measurement cycles. The paper presents differences between each operational measurement and the measurement before putting sections into operation, which indicates a development of track geometry quality.

  1. Water quality real-time monitoring system via biological detection based on video analysis

    Science.gov (United States)

    Xin, Chen; Fei, Yuan

    2017-11-01

    With the development of society, water pollution has become the most serious problem in China. Therefore, real-time water quality monitoring is an important part of human activities and water pollution prevention. In this paper, the behavior of zebrafish was monitored by computer vision. Firstly, the moving target was extracted by the method of saliency detection, and tracked by fitting the ellipse model. Then the motion parameters were extracted by optical flow method, and the data were monitored in real time by means of Hinkley warning and threshold warning. We achieved classification warning through a number of dimensions by comprehensive toxicity index. The experimental results show that the system can achieve more accurate real-time monitoring.

  2. On use of image quality metrics for perceptual blur modeling: image/video compression case

    Science.gov (United States)

    Cha, Jae H.; Olson, Jeffrey T.; Preece, Bradley L.; Espinola, Richard L.; Abbott, A. Lynn

    2018-02-01

    Linear system theory is employed to make target acquisition performance predictions for electro-optical/infrared imaging systems where the modulation transfer function (MTF) may be imposed from a nonlinear degradation process. Previous research relying on image quality metrics (IQM) methods, which heuristically estimate perceived MTF has supported that an average perceived MTF can be used to model some types of degradation such as image compression. Here, we discuss the validity of the IQM approach by mathematically analyzing the associated heuristics from the perspective of reliability, robustness, and tractability. Experiments with standard images compressed by x.264 encoding suggest that the compression degradation can be estimated by a perceived MTF within boundaries defined by well-behaved curves with marginal error. Our results confirm that the IQM linearizer methodology provides a credible tool for sensor performance modeling.

  3. User requirements for objective perceptual video quality measurements in digital cable television

    CERN Document Server

    ITU Telecommunication Standardization Sector (ITU-T). Geneva

    2000-01-01

    The main purpose of this List is to indicate all the ITU-T (and CCITT) Recommendations currently in effect at the date of its publication In addition, it includes the CCITT/ITU-T Supplements which contain operational or other practical/implementation a particular Series of Recommendations. At present, more than 2600 recommendations (standards) on some 60,000 pages are in force. Recommendations are non-binding standards agreed by consensus in technical study groups. ITU-T Recommendations are non-binding, however they are generally complied with due to their high quality and because they guarantee the interconnectivity of networks and enable telecommunication services to be provided on a worldwide scale.

  4. Diagnostic confidence and image quality of CT pulmonary angiography at 100 kVp in overweight and obese patients

    International Nuclear Information System (INIS)

    Megyeri, B.; Christe, A.; Schindera, S.T.; Horkay, E.; Sikula, J.; Cullmann, J.L.; Kollar, J.; Heverhagen, J.T.; Szucs-Farkas, Z.

    2015-01-01

    Aim: To compare image quality and diagnostic confidence of 100 kVp CT pulmonary angiography (CTPA) in patients with body weights (BWs) below and above 100 kg. Materials and methods: The present retrospective study comprised 216 patients (BWs of 75–99 kg, 114 patients; 100–125 kg, 88 patients; >125 kg, 14 patients), who received 100 kVp CTPA to exclude pulmonary embolism. The attenuation was measured and the contrast-to-noise ratio (CNR) was calculated in the pulmonary trunk. Size-specific dose estimates (SSDEs) were evaluated. Three blinded radiologists rated subjective image quality and diagnostic confidence. Results between the BW groups and between three body mass index (BMI) groups (BMI <25 kg/m 2 , BMI = 25–29.9 kg/m 2 , and BMI ≥30 kg/m 2 , i.e., normal weight, overweight, and obese patients) were compared using the Kruskal–Wallis test. Results: Vessel attenuation was higher and SDDE was lower in the 75–99 kg group than at higher BWs (p-values between <0.001 and 0.03), with no difference between the 100–125 and >125 kg groups (p = 0.892 and 1). Subjective image quality and diagnostic confidence were not different among the BW groups (p = 0.225 and 1). CNR was lower (p < 0.006) in obese patients than in normal weight or overweight subjects. Diagnostic confidence was not different in the BMI groups (p = 0.105). Conclusion: CTPA at 100 kVp tube voltage can be used in patients weighing up to 125 kg with no significant deterioration of subjective image quality and confidence. The applicability of 100 kVp in the 125–150 kg BW range needs further testing in larger collectives. - Highlights: • We assessed quality and diagnostic confidence with 100 kVp CTPA at high body weight • Results in 75–99 kg, 100–125 kg and >125 kg groups were compared (216 patients) • Subjective quality and confidence did not differ between the body weight groups • Diagnostic confidence in non-obese and obese patients was not different either • CTPA

  5. Dashboard Videos

    Science.gov (United States)

    Gleue, Alan D.; Depcik, Chris; Peltier, Ted

    2012-01-01

    Last school year, I had a web link emailed to me entitled "A Dashboard Physics Lesson." The link, created and posted by Dale Basier on his "Lab Out Loud" blog, illustrates video of a car's speedometer synchronized with video of the road. These two separate video streams are compiled into one video that students can watch and analyze. After seeing…

  6. Interactive segmentation of tongue contours in ultrasound video sequences using quality maps

    Science.gov (United States)

    Ghrenassia, Sarah; Ménard, Lucie; Laporte, Catherine

    2014-03-01

    Ultrasound (US) imaging is an effective and non invasive way of studying the tongue motions involved in normal and pathological speech, and the results of US studies are of interest for the development of new strategies in speech therapy. State-of-the-art tongue shape analysis techniques based on US images depend on semi-automated tongue segmentation and tracking techniques. Recent work has mostly focused on improving the accuracy of the tracking techniques themselves. However, occasional errors remain inevitable, regardless of the technique used, and the tongue tracking process must thus be supervised by a speech scientist who will correct these errors manually or semi-automatically. This paper proposes an interactive framework to facilitate this process. In this framework, the user is guided towards potentially problematic portions of the US image sequence by a segmentation quality map that is based on the normalized energy of an active contour model and automatically produced during tracking. When a problematic segmentation is identified, corrections to the segmented contour can be made on one image and propagated both forward and backward in the problematic subsequence, thereby improving the user experience. The interactive tools were tested in combination with two different tracking algorithms. Preliminary results illustrate the potential of the proposed framework, suggesting that the proposed framework generally improves user interaction time, with little change in segmentation repeatability.

  7. Video microblogging

    DEFF Research Database (Denmark)

    Bornoe, Nis; Barkhuus, Louise

    2010-01-01

    Microblogging is a recently popular phenomenon and with the increasing trend for video cameras to be built into mobile phones, a new type of microblogging has entered the arena of electronic communication: video microblogging. In this study we examine video microblogging, which is the broadcasting...... of short videos. A series of semi-structured interviews offers an understanding of why and how video microblogging is used and what the users post and broadcast....

  8. Health laboratories in the Tanga region of Tanzania: the quality of diagnostic services for malaria and other communicable diseases

    DEFF Research Database (Denmark)

    Ishengoma, D R S; Rwegoshora, R T; Mdira, K Y

    2009-01-01

    Although critical for good case management and the monitoring of health interventions, the health-laboratory services in sub-Saharan Africa are grossly compromised by poor infrastructures and a lack of trained personnel, essential reagents and other supplies. The availability and quality...... of diagnostic services in 37 health laboratories in three districts of the Tanga region of Tanzania have recently been assessed. The results of the survey, which involved interviews with health workers, observations and a documentary review, revealed that malaria accounted for >50% of admissions and out...... control, none had standard operating procedures (SOP) on display or evidence of such quality assurance. Although malaria was the main health problem, diagnostic services for malaria and other diseases were inadequate and of poor quality because of the limited human resources, poor equipment and shortage...

  9. Radiation safety and quality control assurance in X-ray diagnostics 1998; Saeteilyturvallisuus ja laadunvarmistus roentgendiagnostiikassa 1998

    Energy Technology Data Exchange (ETDEWEB)

    Servomaa, A. [ed.

    1998-03-01

    The report is based on a seminar course of lectures `Radiation safety and quality assurance in X-ray diagnostics 1998` organized by the Radiation and Nuclear Safety Authority (STUK) in Finland. The lectures included actual information on X-ray examinations: methods of quality assurance, methods of measuring and calculating patient doses, examination frequencies, patient doses, occupational doses, and radiation risks. Paediatric X-ray examinations and interventional procedures were the most specific topics. The new Council Directive 97/43/Euratom on medical exposure, and the European Guidelines on quality criteria for diagnostic radiographic images, were discussed in several lectures. Lectures on general radiation threats and preparedness, examples of radiation accidents, and emergency preparedness in hospitals were also included. (editor)

  10. High-resolution, low-delay, and error-resilient medical ultrasound video communication using H.264/AVC over mobile WiMAX networks.

    Science.gov (United States)

    Panayides, Andreas; Antoniou, Zinonas C; Mylonas, Yiannos; Pattichis, Marios S; Pitsillides, Andreas; Pattichis, Constantinos S

    2013-05-01

    In this study, we describe an effective video communication framework for the wireless transmission of H.264/AVC medical ultrasound video over mobile WiMAX networks. Medical ultrasound video is encoded using diagnostically-driven, error resilient encoding, where quantization levels are varied as a function of the diagnostic significance of each image region. We demonstrate how our proposed system allows for the transmission of high-resolution clinical video that is encoded at the clinical acquisition resolution and can then be decoded with low-delay. To validate performance, we perform OPNET simulations of mobile WiMAX Medium Access Control (MAC) and Physical (PHY) layers characteristics that include service prioritization classes, different modulation and coding schemes, fading channels conditions, and mobility. We encode the medical ultrasound videos at the 4CIF (704 × 576) resolution that can accommodate clinical acquisition that is typically performed at lower resolutions. Video quality assessment is based on both clinical (subjective) and objective evaluations.

  11. HbA1c as the diagnostic criterion for diabetes reduces incidence and prevalence of DM2 by 25% but strongly depending on analytical quality

    DEFF Research Database (Denmark)

    Brandslund, Ivan; Nielsen, Aneta Aleksandra; Hyldtoft Petersen, Per

    HbA1c as the diagnostic criterion for diabetes reduces incidence and prevalence of DM2 by 25% but strongly depending on analytical quality......HbA1c as the diagnostic criterion for diabetes reduces incidence and prevalence of DM2 by 25% but strongly depending on analytical quality...

  12. [The quality management in clinical diagnostic laboratory in conditions of the Federal Center of traumatology, orthopedics and endoprosthesis replacement of Minzdrav of Russia (Cheboksary)].

    Science.gov (United States)

    Nikolaev, N S; Nazarova, V V; Dobrovol'skaia, N Iu; Orlova, A V; Pchelova, N N

    2014-10-01

    The article presents experience of clinical diagnostic laboratory of the Federal Center of traumatology, orthopedics and endoprosthesis replacement of Minzdrav of Russia (Cheboksary) in the area of quality management of medical laboratory services on the basis of evaluation of efficacy and effectiveness of processes. The factors effecting quality of functioning of clinical diagnostic laboratory are indicated. The criteria and indicators of efficacy of work of employees of clinical diagnostic laboratory are presented.

  13. Video demystified

    CERN Document Server

    Jack, Keith

    2004-01-01

    This international bestseller and essential reference is the "bible" for digital video engineers and programmers worldwide. This is by far the most informative analog and digital video reference available, includes the hottest new trends and cutting-edge developments in the field. Video Demystified, Fourth Edition is a "one stop" reference guide for the various digital video technologies. The fourth edition is completely updated with all new chapters on MPEG-4, H.264, SDTV/HDTV, ATSC/DVB, and Streaming Video (Video over DSL, Ethernet, etc.), as well as discussions of the latest standards throughout. The accompanying CD-ROM is updated to include a unique set of video test files in the newest formats. *This essential reference is the "bible" for digital video engineers and programmers worldwide *Contains all new chapters on MPEG-4, H.264, SDTV/HDTV, ATSC/DVB, and Streaming Video *Completely revised with all the latest and most up-to-date industry standards.

  14. A Comprehensive Approach Towards Quality and Safety in Diagnostic Imaging Services: Our Experience at a Rural Tertiary Health Care Center.

    Science.gov (United States)

    Patel, Viral; Sindhwani, Geetika; Gupta, Monica; Arora, Sweta; Mishra, Arpita; Bhatt, Jayesh; Arora, Manali; Gehani, Anisha

    2017-08-01

    An organization's transformation from imple-mentation of small, distinct Quality Improvement (QI) efforts to complete incorporation of Quality Improvement Program (QIP) into its culture occurs through a process of churning the foundational elements over time. To develop a quality culture across the employees, identify measurable indicators and various tools to impart effective quality care and develop a learning culture for continuous quality improvement in the field of imaging services. To establish a QIP, the bare minimum requirement started with forming a quality committee. The committee identified the areas of improvement and ascertaining the core principle of Quality Management System (QMS) by having a Quality Manual, Standard Operating Procedures (SOP's), work-instructions, identification and monitoring of quality indicators and a training calendar. Appropriate tools like formatted daily registers, periodic check lists, run charts etc., were developed to collect the data followed by multiple PDSA cycles (Plan, Do, Study and Act) which helped identify the process bottlenecks, followed by implementing solutions and reanalysis. A total of 17 measurable key performance indicators were identified from the four major quality tasks namely Safety, Process Improvement, Professional Outcome and Satisfaction, to assess the performance measures and targets of QIP. Diagnostic services should evaluate how to choose the most appropriate method and develop a comprehensive QIP to meet the needs of the staff and the end users, thus, creating a working environment, where people constitutes the intrinsic value in attaining the ultimate quality and safety.

  15. Quality of audio-assisted versus video-assisted dispatcher-instructed bystander cardiopulmonary resuscitation: A systematic review and meta-analysis.

    Science.gov (United States)

    Lin, Yu-You; Chiang, Wen-Chu; Hsieh, Ming-Ju; Sun, Jen-Tang; Chang, Yi-Chung; Ma, Matthew Huei-Ming

    2018-02-01

    This study aimed to conduct a systematic review and meta-analysis comparing the effect of video-assistance and audio-assistance on quality of dispatcher-instructed cardiopulmonary resuscitation (DI-CPR) for bystanders. Five databases were searched, including PubMed, Cochrane library, Embase, Scopus and NIH clinical trial, to find randomized control trials published before June 2017. Qualitative analysis and meta-analysis were undertaken to examine the difference between the quality of video-instructed and audio-instructed dispatcher-instructed bystander CPR. The database search yielded 929 records, resulting in the inclusion of 9 relevant articles in this study. Of these, 6 were included in the meta-analysis. Initiation of chest compressions was slower in the video-instructed group than in the audio-instructed group (median delay 31.5 s; 95% CI: 10.94-52.09). The difference in the number of chest compressions per minute between the groups was 19.9 (95% CI: 10.50-29.38) with significantly faster compressions in the video-instructed group than in the audio-instructed group (104.8 vs. 80.6). The odds ratio (OR) for correct hand positioning was 0.8 (95% CI: 0.53-1.30) when comparing the audio-instructed and video-instructed groups. The differences in chest compression depth (mm) and time to first ventilation (seconds) between the video-instructed group and audio-instructed group were 1.6 mm (95% CI: -8.75, 5.55) and 7.5 s (95% CI: -56.84, 71.80), respectively. Video-instructed DI-CPR significantly improved the chest compression rate compared to the audio-instructed method, and a trend for correctness of hand position was also observed. However, this method caused a delay in the commencement of bystander-initiated CPR in the simulation setting. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. A comparison of analogue and digital techniques in upper gastrointestinal examinations: absorbed dose and diagnostic quality of the images

    International Nuclear Information System (INIS)

    Axelsson, B.; Hansson, I.B.; Boden, K.; Witt, H.H.; Fransson, S.G.; Persliden, J.

    2000-01-01

    This study was performed to investigate whether patient exposure and diagnostic quality of the image is significantly influenced by the introduction of digital image acquisition techniques. Evaluation was performed for three different techniques (analogue, analogue fluoro+digital radiography, digital) in examination of the upper gastrointestinal tract. The evaluation was done from data acquired in three different departments. Patient exposure was recorded as KERMA-area product (KAP) and the individual patient readings were normalised to a standard size patient. Image quality was assessed using visual grading with a reference image. The recorded KAP values were significantly higher (22.3 Gycm 2 ) for the fully digital technique compared to the others (analogue 6.8 Gycm 2 , analogue+digital 3.6 Gycm 2 ). This was due mostly to an increased number of exposures. The diagnostic quality of the image was, however, also regarded to be slightly lower for the technique giving the lowest patient dose with the smallest number of exposures (analogue+digital). The digital examination technique, as used in this study, thus resulted in significantly higher patient dose without any significant gain in diagnostic quality of the image. (orig.)

  17. A study for determination of various positioning errors in digital panoramic radiography for evaluation of diagnostic image quality

    Directory of Open Access Journals (Sweden)

    Apurva Mohite Khator

    2017-01-01

    Full Text Available Faulty radiographs have poor diagnostic quality, and repetition of such poor-quality radiographs leads to increased patient exposure to radiation. Since digital panoramic radiography has replaced manual radiography, the only hindrance in producing good-quality radiographs is the positioning errors. Objectives: Our study aims to determine the various positioning errors and their relative frequency and to identify those errors directly responsible for diagnostically inadequate images. Materials and Methods: Five hundred panoramic radiographs taken serially (from the year 2007 were retrospectively assessed for the positioning errors by three oral and maxillofacial radiology specialists using a performa enlisting the errors. The three specialists had different duration of clinical experience and they evaluated the orthopantograms as diagnostically acceptable or unacceptable. They also observed the relative frequency of all the positioning errors. Statistical Analysis: The kappa value for intraobserver agreement was calculated, which suggested that the agreement among the observers was fair. Results: Of the 500 panoramic radiographs viewed by the three observers, 25 (5% had no errors, while 475 (95% showed one or more positioning errors. The most common error in our study was found to be head turned to one side (33.8% and the least common error was patient movement during exposure (1.8%. Conclusion: Positioning errors are very common in digital panoramic radiography, and they lead to production of poor-quality radiographs. The operator should take this fact into consideration and spend more time in patient positioning, thereby reducing the repetition of radiographs and unwanted patient exposure.

  18. Intraoperative Video Production With a Head-Mounted Consumer Video Camera.

    Science.gov (United States)

    Avery, Matthew C

    2017-08-01

    The use of high-definition video in surgical education is becoming increasingly popular. Because of the availability of relatively inexpensive, consumer-grade video cameras, surgeons with minimal video production experience can produce high-quality surgical videos. A number of video capture methods are available, with varying degrees of production quality, economic constraint, and level of attention required from the operating surgeon. The accompanying video provides an overview of the advantages and disadvantages of several options and describes a technique for capturing intraoperative video with the use of a head-mounted, consumer video camera.

  19. GoPro Hero Cameras for Creation of a Three-Dimensional, Educational, Neurointerventional Video.

    Science.gov (United States)

    Park, Min S; Brock, Andrea; Mortimer, Vance; Taussky, Philipp; Couldwell, William T; Quigley, Edward

    2017-10-01

    Neurointerventional education relies on an apprenticeship model, with the trainee observing and participating in procedures with the guidance of a mentor. While educational videos are becoming prevalent in surgical cases, there is a dearth of comparable educational material for trainees in neurointerventional programs. We sought to create a high-quality, three-dimensional video of a routine diagnostic cerebral angiogram for use as an educational tool. A diagnostic cerebral angiogram was recorded using two GoPro HERO 3+ cameras with the Dual HERO System to capture the proceduralist's hands during the case. This video was edited with recordings from the video monitors to create a real-time three-dimensional video of both the actions of the neurointerventionalist and the resulting wire/catheter movements. The final edited video, in either two or three dimensions, can serve as another instructional tool for the training of residents and/or fellows. Additional videos can be created in a similar fashion of more complicated neurointerventional cases. The GoPro HERO 3+ camera and Dual HERO System can be used to create educational videos of neurointerventional procedures.

  20. [Quality of diagnostic procedures and frequency of endoscopically defined diseases of the upper gastrointestinal tract].

    Science.gov (United States)

    Bartels, F; Hahn, H-J; Stolte, M; Schmidt-Wilcke, H A

    2003-04-01

    (diagnosis histologically confirmed) were found with the same ratio of the diffuse type and the intestinal type. In 18 patients a carcinoma could be detected in the neighbouring area of gastric ulcers. The endoscopic findings in this investigation do not differ significantly from the results found in literature. It is important that there are more gastric ulcers than duodenal ulcers. This can be explained by the frequent use of PPIs which are prescribed additionally to NSARs and ASS. The deficits of histological diagnostics on Barett's oesophagus and gastritis were remarkable. An improvement of the endoscopic and histologic assessment quality by valid standards systematically applied should be aimed at in future. Furthermore it could be helpful to use the same nomenclature for pathologic findings to intensify the co-operation between the physicians in hospitals and the practitioners.

  1. Towards a Diagnostic Instrument to Identify Improvement Opportunities for Quality Controlled Logistics in Agrifood Supply Chain Networks

    Directory of Open Access Journals (Sweden)

    Jack G.A.J. van der Vorst

    2011-10-01

    Full Text Available  Western-European consumers have become not only more demanding on product availability in retail outlets but also on other food attributes such as quality, integrity, and safety. When (redesigning food supply-chain networks, from a logistics point of view, one has to consider these demands next to traditional efficiency and responsiveness requirements. The concept ‘quality controlled logistics’ (QCL hypothesizes that if product quality in each step of the supply chain can be predicted in advance, goods flows can be controlled in a pro-active manner and better chain designs can be established resulting in higher product availability, constant quality, and less product losses. The paper discusses opportunities of using real-time product quality information for improvement of the design and management of ‘AgriFood Supply Chain Networks’, and presents a preliminary diagnostic instrument for assessment of ‘critical quality’ and ‘logistics control’ points in the supply chain network. Results of a tomato-chain case illustrate the added value of the QCL concept for identifying improvement opportunities in the supply chain as to increase both product availability and quality. Future research aims for the further development of the diagnostic instrument and the quantification of costs and benefits of QCL scenarios.

  2. Evaluation of the Quality Control Program for Diagnostic Radiography and Fluoroscopy Devices in Syria during 2005-2013

    Directory of Open Access Journals (Sweden)

    M. H. Kharita

    2017-06-01

    Full Text Available Introduction: Extensive use of diagnostic radiology is the largest contributor to total population radiation doses. Thus, appropriate equipment and safe practice are necessary for good-quality images with optimal doses. This study aimed to perform quality control (QC audit for radiography and fluoroscopy devices owned by private sector in Syria (2005-2013 to verify compliance of performance of X-ray machines with the regulatory requirements stipulated by the national regulatory body. Materials and Methods: In this study, QC audit included 487 X-ray diagnostic machines, (363 radiography and 124 fluoroscopy devices, installed in 306 medical diagnostic radiology centers in 14 provinces in Syria. We employed an X-ray beam analyzer device (NERO model 8000, Victoreen, USA, which was tested and calibrated at the National Secondary Standard Dosimetry Laboratory traceable to the IAEA Network of Secondary Standard Dosimetry Laboratories. Standard QC tool kits were used to evaluate tube and generator of the X-ray machines, which constituted potential (kVp, timer accuracy, radiation output consistency, tube filtration, small and large focal spot sizes, X-ray beam collimation and alignment, as well as high- and low-resolution and entrance surface dose in fluoroscopy. Results: According to our results, most of the assessed operating parameters were in compliance with the standards stipulated by the National Regulatory Authority. In cases of noncompliance for the assessed parameters, maximum value (28.77% pertained to accuracy of kVp calibration for radiography units, while the lowest value (2.42% belonged to entrance surface dose in fluoroscopy systems. Conclusion: Effective QC program in diagnostic radiology leads to obtaining information regarding quality of radiology devices used for medical diagnosis and minimizing the doses received by patients and medical personnel. The findings of this QC program, as the main part of QA program, illustrated that most

  3. The quality of preoperative diagnostics and surgery and their impact on delays in breast cancer treatment - A population based study.

    Science.gov (United States)

    Ojala, Kaisu; Meretoja, Tuomo J; Mattson, Johanna; Salminen-Peltola, Päivi; Leutola, Suvi; Berggren, Marianne; Leidenius, Marjut H K

    2016-04-01

    This study aims to clarify quality of breast cancer surgery in population-based setting. We aim to elucidate factors influencing waiting periods, and to evaluate the effect of hospital volume on surgical treatment policies. Special interest was given to diagnostic and surgical processes and their impact on waiting times. All 1307 patients having primary breast cancer surgery at the Helsinki and Uusimaa Hospital District during 2010 were included in this retrospective study. Median waiting time for primary surgery was 24 days and significantly affected by additional imaging and diagnostic biopsies as well as hospital volume. Final rate of breast conserving surgery was surprisingly low, 51%, not affected by hospital volume, p = 0.781. Oncoplastic resection and immediate breast reconstruction (IBR) were performed more often in high volume units, p treatment. Quality of preoperative diagnostics play a crucial role in minimizing the need of repeated imaging and biopsies as well as multiple operations. Positive impact of high-volume hospitals becomes evident when analyzing procedures requiring advanced surgical techniques. High-volume hospitals achieved better quality in axillary surgery. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Evaluation of the New DIN Standard for Quality Assurance of Diagnostic Displays - Technical Review DIN 6868-157.

    Science.gov (United States)

    Entz, Kathrin; Sommer, Alexander; Lenzen, Horst

    2018-01-01

    Acceptance and regular constancy tests are necessary to ensure the quality of diagnostic displays. In November 2014, a new standard (DIN 6868-157) was published which defines the test procedure and limiting values. There are several substantial changes compared with the previous standard DIN V 6868-57, i. e. considering the complete image display system including workstation and application software instead of only the displays. Since its publication, the new standard has raised many questions. This technical review aims to show the strengths and weaknesses of the new standard. Positive aspects are the introduction of a limiting value for the illuminance and the extension of the interval for constancy tests from 3 to 6 six months. The daily constancy test on the other hand, raises several problems and should be replaced by a randomized test. Additionally, the medical relevance is critically questioned and an overview of software for the quality assurance will be given.   · Acceptance and constancy tests for diagnostic displays are defined in DIN 6868-157.. · The new standards has positive and negative aspects.. · Randomized tests should be introduced.. · Entz K, Sommer A, Lenzen H. DIN 6868-157: Image Quality Assurance in Diagnostic X-ray Departments - X-ray Ordinance Acceptance and Constancy Test of Image Display Systems in their Environment - Technical Review -. Fortschr Röntgenstr 2018; 190: 51 - 60. © Georg Thieme Verlag KG Stuttgart · New York.

  5. A diagnostic tool for basic daily quality assurance of a Tomotherapy Hi*Art machine.

    Science.gov (United States)

    Van de Vondel, Iwein; Tournel, Koen; Verellen, Dirk; Duchateau, Michael; Lelie, Steven; Storme, Guy

    2009-10-15

    To investigate and evaluate the use of an in-house developed diagnostic software tool using the imaging detector data for a quick daily quality assurance check of the output (dose) and lateral profile (cone) of a tomotherapy Hi*Art system. The Hi*Art treatment system is a radiation therapy machine for delivering intensity modulated radiation therapy (IMRT) in a helical fashion with an integrated CT scanner used for improved patient positioning before treatment. Since the system was developed specifically for IMRT, flat fields can be obtained by modulating the beam and therefore the flattening filter could be omitted. Because of this, the field has a cone-like profile in both lateral and transversal directions. Patients are treated in a helical fashion with a tight pitch and a constant gantry rotation speed, while modulation is performed by a binary MLC. Consequently dose output per time-unit (dose rate) as well as the shape of the cone-profile are very important for correct patient treatment and should be closely monitored. However, using the company-provided initial tools and conventional dosimetry, this can be a time consuming daily procedure. The aim of this work is to develop a fast, automated method of quality assurance based on the detector signal. A software tool called "tomocheck" running on the operation station has been developed to evaluate the output (dose rate) and the lateral cone profile (energy) of the Hi*Art system, comparing actual output and cone profile with a reference (previously approved against ionization chamber measurements). This is done by using the data of the 640 on-board detector array that are directly retrieved and processed after a specific QA procedure. The detector file consists of the CT detector data and the three monitoring dose chamber readings over a time period of 200 sec. To evaluate the method, the system was benchmarked against ionization chamber measurements and classical IMRT QA methods. Action levels (final status

  6. Appropriate diagnostic imaging - Assessment of the quality of referrals from general practice

    DEFF Research Database (Denmark)

    Andersen, Merethe Kirstine Kousgaard; Torfing, Trine; Ulrichsen, Walther

    Background and aim Diagnostic imaging is the second most used paraclinical examination in Denmark and 15% of all referrals from general practice concerns radiology. The fast development in diagnostic imaging constitutes a challenge for general practitioners’ when determining the right type...... modality. Results Four regional radiological departments participated in the study. A total of 785 referrals were reviewed. Most reviews were conducted on x-ray referrals (35%). Diagnostic imaging was considered relevant or very relevant in 73.5% of the reviewed referrals, of which referrals to CT...... to diagnostic imaging were considered relevant from a radiologic perspective. However, there seems to be a potential for development regarding the exhaustiveness of information and modality relevance, particularly for referrals to MRI and ultrasound....

  7. Diagnostic Evaluation of Ozone Production and Horizontal Transport in a Regional Photochemical Air Quality Modeling System

    Science.gov (United States)

    A diagnostic model evaluation effort has been performed to focus on photochemical ozone formation and the horizontal transport process since they strongly impact the temporal evolution and spatial distribution of ozone (O3) within the lower troposphere. Results from th...

  8. Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus.

    NARCIS (Netherlands)

    A.F. van Belkum (Alex); H.G.M. Niesters (Bert); W.G. MacKay (William); W.B. van Leeuwen (Willem)

    2007-01-01

    textabstractTen samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing.

  9. Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    van Belkum, Alex; Niesters, Hubert G M; MacKay, William G; van Leeuwen, Willem B

    Ten samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Samples containing

  10. Combined Scanning Confocal Ultrasound Diagnostic and Treatment System for Bone Quality Assessment and Fracture Healing

    Data.gov (United States)

    National Aeronautics and Space Administration — The objectives of this study are to develop a combined diagnostic and treatment ultrasound technology for early prediction of bone disorder and guided acceleration...

  11. The quest for 'diagnostically lossless' medical image compression: a comparative study of objective quality metrics for compressed medical images

    Science.gov (United States)

    Kowalik-Urbaniak, Ilona; Brunet, Dominique; Wang, Jiheng; Koff, David; Smolarski-Koff, Nadine; Vrscay, Edward R.; Wallace, Bill; Wang, Zhou

    2014-03-01

    Our study, involving a collaboration with radiologists (DK,NSK) as well as a leading international developer of medical imaging software (AGFA), is primarily concerned with improved methods of assessing the diagnostic quality of compressed medical images and the investigation of compression artifacts resulting from JPEG and JPEG2000. In this work, we compare the performances of the Structural Similarity quality measure (SSIM), MSE/PSNR, compression ratio CR and JPEG quality factor Q, based on experimental data collected in two experiments involving radiologists. An ROC and Kolmogorov-Smirnov analysis indicates that compression ratio is not always a good indicator of visual quality. Moreover, SSIM demonstrates the best performance, i.e., it provides the closest match to the radiologists' assessments. We also show that a weighted Youden index1 and curve tting method can provide SSIM and MSE thresholds for acceptable compression ratios.

  12. High Dynamic Range Video

    CERN Document Server

    Myszkowski, Karol

    2008-01-01

    This book presents a complete pipeline forHDR image and video processing fromacquisition, through compression and quality evaluation, to display. At the HDR image and video acquisition stage specialized HDR sensors or multi-exposure techniques suitable for traditional cameras are discussed. Then, we present a practical solution for pixel values calibration in terms of photometric or radiometric quantities, which are required in some technically oriented applications. Also, we cover the problem of efficient image and video compression and encoding either for storage or transmission purposes, in

  13. Impact of recombinant TSH on quality of life in thyroid carcinoma patients undergoing remnant ablation or diagnostic whole body scanning

    International Nuclear Information System (INIS)

    Schroeder, Pamela R.; Ladenson, Paul W.; for the Members of the Thyrogen Trials

    2005-01-01

    Full text: Thyroid remnant ablation with 131 I is often necessary in the initial treatment of thyroid carcinoma. A recent study demonstrated that use of recombinant TSH (rh TSH) was equivalently effective to withdrawal from levothyroxine (L-T 4 ) for postoperative remnant ablation. Quality of life was also shown to be negatively impacted in patients withdrawn from L-T 4 , but not those maintained euthyroid and treated after rh TSH. In this study, we compare the impact of rh TSH on quality of life in patients undergoing remnant ablation versus those undergoing diagnostic whole body scanning (WBS) in a previous trial. Health-related quality of life was measured using the SF-36 survey, which consists of 8 domains describing the physical and mental functioning of patients and 2 physical and mental summary domains, in both trials at baseline on L-T 4 , after rh TSH while on L-T 4 and after L-T 4 withdrawal. Mean SF-36 scores declined from the rh TSH treatment versus L-T 4 withdrawal in both trials to a similar extent in all 8 domains and the 2 summary domains, as evidenced by overlapping 95% confidence intervals. Further SF-6D scores, which summarize all 8 domains in a single zero-to-one metric, were used to characterize the overall quality of life among patients in the two trials. The SF-6D scores for patients after rh TSH administration in the diagnostic and ablation trials were 0.803 and 0.714, respectively. In contrast, SF-6D scores for patients undergoing L-T 4 withdrawal in the diagnostic and ablation trials were 0.637 and 0.548, respectively (p 4 withdrawal both experience a comparable decrease in quality of life, which can be prevented by use of rh TSH in the euthyroid state. (author)

  14. Health laboratories in the Tanga region of Tanzania: the quality of diagnostic services for malaria and other communicable diseases.

    Science.gov (United States)

    Ishengoma, D R S; Rwegoshora, R T; Mdira, K Y; Kamugisha, M L; Anga, E O; Bygbjerg, I C; Rønn, A M; Magesa, S M

    2009-07-01

    Although critical for good case management and the monitoring of health interventions, the health-laboratory services in sub-Saharan Africa are grossly compromised by poor infrastructures and a lack of trained personnel, essential reagents and other supplies. The availability and quality of diagnostic services in 37 health laboratories in three districts of the Tanga region of Tanzania have recently been assessed. The results of the survey, which involved interviews with health workers, observations and a documentary review, revealed that malaria accounted for >50% of admissions and out-patient visits. Most (92%) of the laboratories were carrying out malaria diagnosis and 89% were measuring haemoglobin concentrations but only one (3%) was conducting culture and sensitivity tests, and those only on urine and pus samples. Only 14 (17%) of the 84 people found working in the visited laboratories were laboratory technologists with a diploma certificate or higher qualification. Sixteen (43%) of the study laboratories each had five or fewer types of equipment and only seven (19%) had more than 11 types each. Although 11 (30%) of the laboratories reported that they conducted internal quality control, none had standard operating procedures (SOP) on display or evidence of such quality assurance. Although malaria was the main health problem, diagnostic services for malaria and other diseases were inadequate and of poor quality because of the limited human resources, poor equipment and shortage of supplies. If the health services in Tanga are not to be overwhelmed by the progressively increasing burden of HIV/AIDS, malaria, tuberculosis and other emerging and re-emerging diseases, more funding and appropriate policies to improve the availability and quality of the area's diagnostic services will clearly be required.

  15. External quality assurance for HIV point-of-care testing in Africa: A collaborative country-partner approach to strengthen diagnostic services

    Directory of Open Access Journals (Sweden)

    Debrah I. Boeras

    2016-10-01

    Full Text Available It is important to consider the role of diagnostics and the critical need for quality diagnostics services in resource-limited settings. Accurate diagnostic tests play a key role in patient management and the prevention and control of most infectious diseases. As countries plan for implementation of HIV early infant diagnosis and viral load point-of-care testing, the London School of Hygiene & Tropical Medicine has worked with countries and partners with an interest in external quality assurance to support quality point-of-care testing on the continent. Through a series of collaborative consultations and workshops, the London School of Hygiene & Tropical Medicine has gathered lessons learned, tools, and resources and developed quality assurance models that will support point-of-care testing. The London School of Hygiene & Tropical Medicine is committed to the continued advancement of laboratory diagnostics in Africa and quality laboratory services and point-of-care testing.

  16. External quality assurance for HIV point-of-care testing in Africa: A collaborative country-partner approach to strengthen diagnostic services.

    Science.gov (United States)

    Boeras, Debrah I; Peeling, Rosanna W

    2016-01-01

    It is important to consider the role of diagnostics and the critical need for quality diagnostics services in resource-limited settings. Accurate diagnostic tests play a key role in patient management and the prevention and control of most infectious diseases. As countries plan for implementation of HIV early infant diagnosis and viral load point-of-care testing, the London School of Hygiene & Tropical Medicine has worked with countries and partners with an interest in external quality assurance to support quality point-of-care testing on the continent. Through a series of collaborative consultations and workshops, the London School of Hygiene & Tropical Medicine has gathered lessons learned, tools, and resources and developed quality assurance models that will support point-of-care testing. The London School of Hygiene & Tropical Medicine is committed to the continued advancement of laboratory diagnostics in Africa and quality laboratory services and point-of-care testing.

  17. Comparison of diagnostic quality and accuracy in color-coded versus gray-scale DCE-MR imaging display

    Energy Technology Data Exchange (ETDEWEB)

    Mehndiratta, A. [German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg (Germany); Indian Institute of Technology (IIT), School of Medical Science and Technology, Kharagpur (India); Knopp, M.V. [The Ohio State University, Department of Radiology, Columbus (United States); Zechmann, C.M.; Owsijewitsch, M.; Tengg-Kobligk, H. von; Zamecnik, P.; Kauczor, H.U. [German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg (Germany); Choyke, P.L. [National Institutes of Health, Clinical Center, Bethesda (United States); Giesel, F.L. [German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg (Germany); National Institutes of Health, Clinical Center, Bethesda (United States)

    2009-09-15

    The purpose of this study was to evaluate the diagnostic value and tumor-vascular display properties (microcirculation) of two different functional MRI post-processing and display (color and gray-scale display) techniques used in oncology. The study protocol was approved by the IRB and written informed consent was obtained from all patients. 38 dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) data sets of patients with malignant pleural-mesothelioma were acquired and post-processed. DCE-MRI was performed at 1.5 tesla with a T1-weighted 2D gradient-echo-sequence (TR 7.0 ms, TE 3.9 ms, 15 axial slices, 22 sequential repetitions), prior and during chemotherapy. Subtracting first image of contrast-enhanced-dynamic series from the last, produced gray-scale images. Color images were produced using a pharmacokinetic two-compartment model. Eight raters, blinded to diagnosis, by visual assessment of post-processed images evaluated both diagnostic quality of the images and vasculature of the tumor using a rating scale ranging from -5 to +5. The scores for vasculature were assessed by correlating with the maximum amplitude of the total-tumor-ROI for accuracy. Color coded images were rated as significantly higher in diagnostic quality and tumor vascular score than gray-scale images (p<0.001, 0.005). ROI signal amplitude analysis and vascular ratings on color coded images were better correlated compared to gray-scale images rating (p<0.05). Color coded images were shown to have higher diagnostic quality and accuracy with respect to tumor vasculature in DCE-MRI, therefore their implementation in clinical assessment and follow-up should be considered for wider application. (orig.)

  18. Assessment of the image quality and diagnostic accuracy of coronary CT angiography: effect of sublingual administration of nitroglycerin

    International Nuclear Information System (INIS)

    Kang, Doo Kyung; Rho, Hyun Woo; Park, Kyung Joo; Choi, So Yeon

    2007-01-01

    We wanted to investigate the effect of sublingual nitroglycerin (NTG) on improving the image quality and diagnostic accuracy of coronary computed tomographic angiography (CTA) for detecting atherosclerosis and significant stenosis. We retrospectively assessed the data of 81 patients who underwent coronary CTA. Forty three patients underwent coronary CTA without medication (the non-administrated group), while 38 patients were given 0.6 mg NTG sublingually before coronary CTA (the administrated group). Image quality was assessed using a five-point grading scale. We evaluated the diagnostic performance of coronary CTA for assessing atherosclerosis and significant stenosis (≥ 50%) in the 42 patients who underwent invasive coronary angiography. The mean image-quality grades were 4.09 ± 0.72 and 4.50 ± 0.60 in the non-administrated and administrated groups, respectively (ρ 0.008). On the per-artery analysis, the accuracy percentages for detecting coronary CTA were 65 and 88% for atherosclerosis and 82 and 80% for significant stenosis in the non-administrated and administrated groups, respectively. On the per-patient analysis, the positive predictive values for coronary CTA were 80% and 100% for atherosclerosis and 77% and 88% for significant stenosis in the non-administrated and administrated groups, respectively. Coronary CTA with NTG administration improved the image quality. The accuracy of coronary CTA for detecting atherosclerosis was higher in the administrated group than in the non-administrated group

  19. [Comparison of diagnostic quality in hysterosalpingography between iodinated non-ionic contrast media with low and high osmolarity].

    Science.gov (United States)

    Piccotti, K; Guida, D; Carbonetti, F; Stefanetti, L; Macioce, A; Cremona, A; David, V

    Comparison of diagnostic quality in hysterosalpingography between low and high-osmolality contrast media. We performed a retrospective evaluation of two cohorts of patients who underwent HSG using contrast media with different osmolarity: the first group ,47 patients, underwent hysterosalpingography in the period September 2011-December 2012 using Iopromide 370 mg/ml; the second group, 50 patients, underwent HSG from January 2013 to October 2013 using Iomeprol 400 mg/ml. Three radiologists, in consensus reading,, reviewed the radiographs by assessing the following four parameters: opacification of the uterine cavity, uterine profiles definition, Fallopian tubes visualization, contrast media spillage into peritoneum. A score-scale from 0 to 3 was assigned for each of the mentioned parameter (0 = minimum non-diagnostic exam, 1 = sufficient examination; 2 = good quality examination; maximum 3 = high quality images). We documented a statistically significant higher quality in displaying Fallopian tubes among patients studied through high osmolarity contrast medium (Iopromide 370 mg/ml) than what obtained through lower osmolarity contrast medium (Iomeprol 400 mg/ml). The use of high osmolarity contrast medium enabled better visualization of the tubes and a greater number of diagnoses of chronic aspecific salpigintis due to the increased osmolality and viscosity of Iomeprol 400 mg/ml. There were no significant differences between the two contrast agents in the evaluation of intra-uterine pathology and in the evaluation of the tubal patency.

  20. Service Quality Of Diagnostic Fine Needle Aspiration Cytology In A Tertiary Care Hospital Of Lahore (Process Measure As Patient's Perspective).

    Science.gov (United States)

    Rizvi, Zainab; Usmani, Rabia Arshed; Rizvi, Amna; Wazir, Salim; Zahra, Taskeen; Rasool, Hafza

    2017-01-01

    Quality of any service is the most important aspect for the manufacturer as well as the consumer. The primary objective of any nation's health system is to provide supreme quality health care services to its patients. The objective of this study was to assess the quality of diagnostic fine needle aspiration cytology service in a tertiary care hospital. As Patient's perspectives provide valuable information on quality of process, therefore, patient's perception in terms of satisfaction with the service was measured. In this cross sectional analytical study, 291 patients undergoing fine needle aspiration cytology in Mayo Hospital were selected by systematic sampling technique. Information regarding satisfaction of patients with four dimensions of service quality process, namely "procedure, sterilization, conduct and competency of doctor" was collected through interview on questionnaire. The questionnaire was developed on SERVQUAL model, a measurement tool, for quality assessment of services provided to patients. All items were assessed on 2- point likert scale (0=dissatisfied, 1=satisfied). Frequencies and percentages of satisfied and dissatisfied patients were recorded for each item and all items in each dimension were scored. If the percentage of sum of all item scores of a dimension was ≥60, the dimension was 'good quality'. Whereas <60% was 'poor quality' dimension. Data was analysed using epi-info-3.5.1. Fisher test was applied to check statistical significance. (p-value <0.05). Out of the 4 dimensions of service quality process, Procedure (48.8%), Sterilization (51.5%) and practitioner conduct (50.9%) were perceived as 'poor' by the patients. Only practitioner competency (67.4%) was perceived as 'good'. Comparison of dimensions of service quality scoring with overall level of patient satisfaction revealed that all 4 dimensions were significantly related to patient dissatisfaction (p<.05). The study suggests that service quality of therapeutic and diagnostic

  1. A comparison of the quality of image acquisition between the incident dark field and sidestream dark field video-microscopes

    NARCIS (Netherlands)

    E. Gilbert-Kawai; J. Coppel (Jonny); V. Bountziouka (Vassiliki); C. Ince (Can); D. Martin (Daniel)

    2016-01-01

    markdownabstract__Background__ The ‘Cytocam’ is a third generation video-microscope, which enables real time visualisation of the in vivo microcirculation. Based upon the principle of incident dark field (IDF) illumination, this hand held computer-controlled device was designed to address the

  2. A comparison of the quality of image acquisition between the incident dark field and sidestream dark field video-microscopes

    NARCIS (Netherlands)

    Gilbert-Kawai, Edward; Coppel, Jonny; Bountziouka, Vassiliki; Ince, Can; Martin, Daniel; Ahuja, V.; Aref-Adib, G.; Burnham, R.; Chisholm, A.; Clarke, K.; Coates, D.; Coates, M.; Cook, D.; Cox, M.; Dhillon, S.; Dougall, C.; Doyle, P.; Duncan, P.; Edsell, M.; Edwards, L.; Evans, L.; Gardiner, P.; Grocott, M.; Gunning, P.; Hart, N.; Harrington, J.; Harvey, J.; Holloway, C.; Howard, D.; Hurlbut, D.; Imray, C.; Jonas, M.; van der Kaaij, J.; Khosravi, M.; Kolfschoten, N.; Levett, D.; Luery, H.; Luks, A.; Martin, D.; McMorrow, R.; Meale, P.; Mitchell, K.; Montgomery, H.; Morgan, G.; Morgan, J.; Murray, A.; Mythen, M.; Newman, S.; O'Dwyer, M.; Pate, J.; Plant, T.; Pun, M.; Richards, P.; Richardson, A.; Rodway, G.; Simpson, J.; Stroud, C.; Stroud, M.; Stygal, J.; Symons, B.; Szawarski, P.; van Tulleken, A.; van Tulleken, C.; Vercueil, A.; Wandrag, L.; Wilson, M.; Windsor, J.; Basnyat, B.; Clarke, C.; Hornbein, T.; Milledge, J.; West, J.; Abraham, S.; Adams, T.; Anseeuw, W.; Astin, R.; Burdall, O.; Carroll, J.; Cobb, A.; Coppel, J.; Couppis, O.; Court, J.; Cumptsey, A.; Davies, T.; Diamond, N.; Geliot, T.; Gilbert-Kawai, E.; Gilbert-Kawai, G.; Gnaiger, E.; Haldane, C.; Hennis, P.; Horscroft, J.; Jack, S.; Jarvis, B.; Jenner, W.; Jones, G.; Kenth, J.; Kotwica, A.; Kumar, R. B. C.; Lacey, J.; Laner, V.; Mahomed, Z.; Moonie, J.; Mythen, P.; O'Brien, K.; Ruggles-Brice, I.; Salmon, K.; Sheperdigian, A.; Smedley, T.; Tomlinson, C.; Ward, S.; Wight, A.; Wilkinson, C.; Wythe, S.; Feelisch, M.; Hanson, M.; Moon, R.; Peters, M.

    2016-01-01

    Background: The 'Cytocam' is a third generation video-microscope, which enables real time visualisation of the in vivo microcirculation. Based upon the principle of incident dark field (IDF) illumination, this hand held computer-controlled device was designed to address the technical limitations of

  3. Communication Modes, Persuasiveness, and Decision-Making Quality: A Comparison of Audio Conferencing, Video Conferencing, and a Virtual Environment

    Science.gov (United States)

    Lockwood, Nicholas S.

    2011-01-01

    Geographically dispersed teams rely on information and communication technologies (ICTs) to communicate and collaborate. Three ICTs that have received attention are audio conferencing (AC), video conferencing (VC), and, recently, 3D virtual environments (3D VEs). These ICTs offer modes of communication that differ primarily in the number and type…

  4. Immersive video

    Science.gov (United States)

    Moezzi, Saied; Katkere, Arun L.; Jain, Ramesh C.

    1996-03-01

    Interactive video and television viewers should have the power to control their viewing position. To make this a reality, we introduce the concept of Immersive Video, which employs computer vision and computer graphics technologies to provide remote users a sense of complete immersion when viewing an event. Immersive Video uses multiple videos of an event, captured from different perspectives, to generate a full 3D digital video of that event. That is accomplished by assimilating important information from each video stream into a comprehensive, dynamic, 3D model of the environment. Using this 3D digital video, interactive viewers can then move around the remote environment and observe the events taking place from any desired perspective. Our Immersive Video System currently provides interactive viewing and `walkthrus' of staged karate demonstrations, basketball games, dance performances, and typical campus scenes. In its full realization, Immersive Video will be a paradigm shift in visual communication which will revolutionize television and video media, and become an integral part of future telepresence and virtual reality systems.

  5. An internationally recognized quality assurance system for diagnostic parasitology in animal health and food safety, with example data on trichinellosis.

    Science.gov (United States)

    Gajadhar, Alvin A; Forbes, Lorry B

    2002-01-03

    A quality assurance (QA) system was developed for diagnostic parasitology and implemented for several diagnostic assays including fecal flotation and sedimentation assays, trichomonad culture assay, and the testing of pork and horse meat for Trichinella to facilitate consistently reliable results. The system consisted of a validated test method, procedures to confirm laboratory capability, and protocols for documentation, reporting, and monitoring. Specific system components included a quality assurance manual, training program, proficiency panels, inter-laboratory check-sample exchange program, assay critical control points, controls, and audits. The quality assurance system of the diagnostic laboratory was audited according to ISO/IEC Standard 17025 by an international third party accrediting body and accredited as a testing laboratory for the specific parasitology tests. Test results generated from the laboratory were reliable and scientifically defensible according to the defined parameters of the tests and were therefore valid for a variety of purposes, including food safety, international trade, and declaration of disease status in an animal, herd, farm, or region. The system was applicable to various test methods for the detection of parasites in feces or other samples, and a digestion test system developed for Trichinella was used as an example. A modified tissue digestion assay was developed, validated, and implemented by the Canadian Food Inspection Agency's Centre for Animal Parasitology for efficiency and quality assurance. The details of the method were properly documented for routine testing and consisted of a homogenization process, an incubation at 45+/-2 degrees C, and two sequential sedimentations in separatory funnels to concentrate and clarify final aliquots for microscopic examination. To facilitate consistently reliable test results, 14 critical control points were identified and monitored, analysts were certified, and the test system verified

  6. Overview of quality assurance in diagnostic medical x-ray examinations

    International Nuclear Information System (INIS)

    Benson, J.S.

    1975-01-01

    Quality assurance is defined as reduction of patient exposure and improvement in film quality. The history of quality assurance programs is briefly reviewed. The Dental Exposure Normalization Technique for improving dental practices and dental equipment is discussed. Data on exposure of patients to medical radiation show wide variations. Some causes of poor film quality are inconsistent machine output, poor beam alignment, timer inaccuracy, improper film-screen combination, and poor film-screen contact

  7. Quality and Safety in Health Care, Part XIV: The External Environment and Research for Diagnostic Processes.

    Science.gov (United States)

    Harolds, Jay A

    2016-09-01

    The work system in which diagnosis takes place is affected by the external environment, which includes requirements such as certification, accreditation, and regulations. How errors are reported, malpractice, and the system for payment are some other aspects of the external environment. Improving the external environment is expected to decrease errors in diagnosis. More research on improving the diagnostic process is needed.

  8. Use of a glass dosimeter for quality control in diagnostic x-ray

    International Nuclear Information System (INIS)

    Ariga, E.; Mano, A.; Niimi, T.; Hioki, T.

    2000-01-01

    were as follows: (1) estimated entrance surface doses with NDD-M about the previous experiment, (2) compared one of the data between 30 and 35 keV with the result of NDD-M and GD-403, and got the calibration factor for NDD-M(f), (3) calibrated all the results of NDD-M with each calibration factor. We compared the results of estimating entrance surface doses with the result we got before and after our calibration, as the relative ratio based on the result of the chamber. It was proved that the distribution of after calibration was shifted parallel on the calibration point and was given as less than ±10% with the result of the chamber. In conclusion, I should note that the glass dosimeter can be used for quality control in diagnostic X-ray at least 28 to 35 keV. In addition, it is possible to calibrate NDD-M with the results. (author)

  9. Asperger syndrome in males over two decades: Quality of life in relation to diagnostic stability and psychiatric comorbidity.

    Science.gov (United States)

    Helles, Adam; Gillberg, I Carina; Gillberg, Christopher; Billstedt, Eva

    2017-05-01

    This study examined objective quality of life (work, academic success, living situation, relationships, support system) and subjective quality of life (Sense of Coherence and Short-Form Health Survey-36) in an adult sample of males ( n = 50, mean age: 30 years) with Asperger syndrome diagnosed in childhood and followed prospectively over two decades. The association between long-term diagnostic stability of an autism spectrum disorder and/or comorbid psychiatric disorders with quality of life was also examined. The results showed great variability as regards quality of life. The subsample that no longer fulfilled an autism spectrum disorder had full-time jobs or studies (10/11), independent living (100%), and reported having two or more friends (100%). In the stable autism spectrum disorder group, 41% had full-time job or studies, 51% lived independently, and 33% reported two or more friends, and a significant minority had specialized employments, lived with support from the government, or had no friends. Academic success was positively correlated with IQ. A majority of the total group scored average Sense of Coherence scores, and the mean for Short-Form Health Survey-36 was above average regarding psychical health and below average regarding mental health. Stability of autism spectrum disorder diagnosis was associated with objective but not subjective quality of life, while psychiatric comorbidity was associated with subjective but not objective quality of life.

  10. Radiation protection and quality assurance in diagnostic radiology - an IAEA coordinated research project in Asia and Eastern Europe

    International Nuclear Information System (INIS)

    Oresegun, Modupe; LeHeron, J.; Maccia, C.; Padovani, R.; Vano, E.

    1999-01-01

    The International Atomic Energy Agency currently has two parallel Coordinated Research Projects (CRP) running in Asia and Eastern Europe. The main objective of the CRPs is to raise the level of awareness in participating countries about the need for radiation protection for patients undergoing diagnostic radiology procedures. This is to be achieved by first assessing the status quo in a sample of hospitals and X-ray rooms in each participating country. A program of optimization of radiation protection for patients is then introduced by means of a comprehensive quality assurance program and the implementation of appropriate dose reduction methods, taking into account clinical requirements for diagnostically acceptable images. Patient dose assessment and image quality assessment are to be performed both before and after the introduction of the quality assurance program. The CRP is divided into two phases - the first is concerned with conventional radiography, while the second involves fluoroscopy and computed tomography. The CRP is still running, restricting the scope of this paper to a discussion of the approach being taken with the project. The project will be completed in 1998, with analysis to follow

  11. Dashboard Videos

    Science.gov (United States)

    Gleue, Alan D.; Depcik, Chris; Peltier, Ted

    2012-11-01

    Last school year, I had a web link emailed to me entitled "A Dashboard Physics Lesson." The link, created and posted by Dale Basier on his Lab Out Loud blog, illustrates video of a car's speedometer synchronized with video of the road. These two separate video streams are compiled into one video that students can watch and analyze. After seeing this website and video, I decided to create my own dashboard videos to show to my high school physics students. I have produced and synchronized 12 separate dashboard videos, each about 10 minutes in length, driving around the city of Lawrence, KS, and Douglas County, and posted them to a website.2 Each video reflects different types of driving: both positive and negative accelerations and constant speeds. As shown in Fig. 1, I was able to capture speed, distance, and miles per gallon from my dashboard instrumentation. By linking this with a stopwatch, each of these quantities can be graphed with respect to time. I anticipate and hope that teachers will find these useful in their own classrooms, i.e., having physics students watch the videos and create their own motion maps (distance-time, speed-time) for study.

  12. Video games

    OpenAIRE

    Kolář, Vojtěch

    2012-01-01

    This thesis is based on a detailed analysis of various topics related to the question of whether video games can be art. In the first place it analyzes the current academic discussion on this subject and confronts different opinions of both supporters and objectors of the idea, that video games can be a full-fledged art form. The second point of this paper is to analyze the properties, that are inherent to video games, in order to find the reason, why cultural elite considers video games as i...

  13. [THE VIRTUAL CYTOLOGIC SLIDES FOR EXTERNAL EVALUATION OF QUALITY OF IMPLEMENTATION OF CYTOLOGIC ANALYSES IN CLINICAL DIAGNOSTIC LABORATORIES: POSSIBILITIES AND PERSPECTIVES].

    Science.gov (United States)

    Djangirova, T V; Shabalova, I P; Pronichev, A N; Polyakov, E V

    2015-08-01

    The article considers application of technology of analysis of cytological slides in external quality control of clinical diagnostic laboratories. The advantages of virtual slides are demonstrated against other applied technologies of external evaluation of quality i.e. slide plate and digital micro-photography. The conditions of formation of virtual slides for external evaluation of quality of clinical diagnostic laboratories. The technology of their application is described. The success of practical application of considered technology in the Federal system of external evaluation of quality is emphasized.

  14. Low-latency video transmission over high-speed WPANs based on low-power video compression

    DEFF Research Database (Denmark)

    Belyaev, Evgeny; Turlikov, Andrey; Ukhanova, Ann

    2010-01-01

    This paper presents latency-constrained video transmission over high-speed wireless personal area networks (WPANs). Low-power video compression is proposed as an alternative to uncompressed video transmission. A video source rate control based on MINMAX quality criteria is introduced. Practical r...... results for video encoder based on H.264/AVC standard are also given....

  15. Quality Control of Direct Molecular Diagnostics for Methicillin-Resistant Staphylococcus aureus▿

    Science.gov (United States)

    van Belkum, Alex; Niesters, Hubert G. M.; MacKay, William G.; van Leeuwen, Willem B.

    2007-01-01

    Ten samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Samples containing 102 to 103 MRSA cells were frequently reported to be negative. MRSE samples were scored as negative by all commercial tests but by only two out of three in-house tests. PMID:17581936

  16. Effectiveness of slow motion video compared to real time video in improving the accuracy and consistency of subjective gait analysis in dogs

    Directory of Open Access Journals (Sweden)

    D.M. Lane

    2015-11-01

    Full Text Available Objective measures of canine gait quality via force plates, pressure mats or kinematic analysis are considered superior to subjective gait assessment (SGA. Despite research demonstrating that SGA does not accurately detect subtle lameness, it remains the most commonly performed diagnostic test for detecting lameness in dogs. This is largely because the financial, temporal and spatial requirements for existing objective gait analysis equipment makes this technology impractical for use in general practice. The utility of slow motion video as a potential tool to augment SGA is currently untested. To evaluate a more accessible way to overcome the limitations of SGA, a slow motion video study was undertaken. Three experienced veterinarians reviewed video footage of 30 dogs, 15 with a diagnosis of primary limb lameness based on history and physical examination, and 15 with no indication of limb lameness based on history and physical examination. Four different videos were made for each dog, demonstrating each dog walking and trotting in real time, and then again walking and trotting in 50% slow motion. For each video, the veterinary raters assessed both the degree of lameness, and which limb(s they felt represented the source of the lameness. Spearman’s rho, Cramer’s V, and t-tests were performed to determine if slow motion video increased either the accuracy or consistency of raters’ SGA relative to real time video. Raters demonstrated no significant increase in consistency or accuracy in their SGA of slow motion video relative to real time video. Based on these findings, slow motion video does not increase the consistency or accuracy of SGA values. Further research is required to determine if slow motion video will benefit SGA in other ways.

  17. Head-camera video recordings of trauma core competency procedures can evaluate surgical resident's technical performance as well as colocated evaluators.

    Science.gov (United States)

    Mackenzie, Colin F; Pasley, Jason; Garofalo, Evan; Shackelford, Stacy; Chen, Hegang; Longinaker, Nyaradzo; Granite, Guinevere; Pugh, Kristy; Hagegeorge, George; Tisherman, Samuel A

    2017-07-01

    Unbiased evaluation of trauma core competency procedures is necessary to determine if residency and predeployment training courses are useful. We tested whether a previously validated individual procedure score (IPS) for individual procedure vascular exposure and fasciotomy (FAS) performance skills could discriminate training status by comparing IPS of evaluators colocated with surgeons to blind video evaluations. Performance of axillary artery (AA), brachial artery (BA), and femoral artery (FA) vascular exposures and lower extremity FAS on fresh cadavers by 40 PGY-2 to PGY-6 residents was video-recorded from head-mounted cameras. Two colocated trained evaluators assessed IPS before and after training. One surgeon in each pretraining tertile of IPS for each procedure was randomly identified for blind video review. The same 12 surgeons were video-recorded repeating the procedures less than 4 weeks after training. Five evaluators independently reviewed all 96 randomly arranged deidentified videos. Inter-rater reliability/consistency, intraclass correlation coefficients were compared by colocated versus video review of IPS, and errors. Study methodology and bias were judged by Medical Education Research Study Quality Instrument and the Quality Assessment of Diagnostic Accuracy Studies criteria. There were no differences (p ≥ 0.5) in IPS for AA, FA, FAS, whether evaluators were colocated or reviewed video recordings. Evaluator consistency was 0.29 (BA) - 0.77 (FA). Video and colocated evaluators were in total agreement (p = 1.0) for error recognition. Intraclass correlation coefficient was 0.73 to 0.92, dependent on procedure. Correlations video versus colocated evaluations were 0.5 to 0.9. Except for BA, blinded video evaluators discriminated (p Education Research Study Quality Instrument criteria scored 15.5/19, Quality Assessment of Diagnostic Accuracy Studies 2 showed low bias risk. Video evaluations of AA, FA, and FAS procedures with IPS are unbiased, valid, and

  18. Recombinant human G6PD for quality control and quality assurance of novel point-of-care diagnostics for G6PD deficiency

    OpenAIRE

    Kahn, Maria; LaRue, Nicole; Zhu, Changcheng; Pal, Sampa; Mo, Jack S.; Barrett, Lynn K.; Hewitt, Steve N.; Dumais, Mitchell; Hemmington, Sandra; Walker, Adrian; Joynson, Jeff; Leader, Brandon T.; Van Voorhis, Wesley C.; Domingo, Gonzalo J.

    2017-01-01

    Background A large gap for the support of point-of-care testing is the availability of reagents to support quality control (QC) of diagnostic assays along the supply chain from the manufacturer to the end user. While reagents and systems exist to support QC of laboratory screening tests for glucose-6-phosphate dehydrogenase (G6PD) deficiency, they are not configured appropriately to support point-of-care testing. The feasibility of using lyophilized recombinant human G6PD as a QC reagent in n...

  19. Routine internal- and external-quality control data in clinical laboratories for estimating measurement and diagnostic uncertainty using GUM principles.

    Science.gov (United States)

    Magnusson, Bertil; Ossowicki, Haakan; Rienitz, Olaf; Theodorsson, Elvar

    2012-05-01

    Healthcare laboratories are increasingly joining into larger laboratory organizations encompassing several physical laboratories. This caters for important new opportunities for re-defining the concept of a 'laboratory' to encompass all laboratories and measurement methods measuring the same measurand for a population of patients. In order to make measurement results, comparable bias should be minimized or eliminated and measurement uncertainty properly evaluated for all methods used for a particular patient population. The measurement as well as diagnostic uncertainty can be evaluated from internal and external quality control results using GUM principles. In this paper the uncertainty evaluations are described in detail using only two main components, within-laboratory reproducibility and uncertainty of the bias component according to a Nordtest guideline. The evaluation is exemplified for the determination of creatinine in serum for a conglomerate of laboratories both expressed in absolute units (μmol/L) and relative (%). An expanded measurement uncertainty of 12 μmol/L associated with concentrations of creatinine below 120 μmol/L and of 10% associated with concentrations above 120 μmol/L was estimated. The diagnostic uncertainty encompasses both measurement uncertainty and biological variation, and can be estimated for a single value and for a difference. This diagnostic uncertainty for the difference for two samples from the same patient was determined to be 14 μmol/L associated with concentrations of creatinine below 100 μmol/L and 14 % associated with concentrations above 100 μmol/L.

  20. Quality control assessment of diagnostic X-ray facilities in Ghana ...

    African Journals Online (AJOL)

    Twenty-three X-ray machines located at 20 different hospitals in Ghana were assessed for quality assurance and control. The radiographic parameters evaluated were tube voltage and current, tube output consistency variation with kilovoltage (kV) and current-time (mAs) factor, exposure time accuracy and beam quality as ...

  1. Quality assurance and image improvement in diagnostic radiology with X-rays

    International Nuclear Information System (INIS)

    Evans, S.H.

    1988-01-01

    Basic quality assurance tests for x-ray sets are considered (tube potential, timing, output, H-V layer, focal-spot size, alignment and perpendicularity of the light-beam diaphragm) together with more specific quality-assurance tests such as tomographic tests, image intensifier and mammographic tests. (UK)

  2. [Quality management and strategic consequences of assessing documentation and coding under the German Diagnostic Related Groups system].

    Science.gov (United States)

    Schnabel, M; Mann, D; Efe, T; Schrappe, M; V Garrel, T; Gotzen, L; Schaeg, M

    2004-10-01

    The introduction of the German Diagnostic Related Groups (D-DRG) system requires redesigning administrative patient management strategies. Wrong coding leads to inaccurate grouping and endangers the reimbursement of treatment costs. This situation emphasizes the roles of documentation and coding as factors of economical success. The aims of this study were to assess the quantity and quality of initial documentation and coding (ICD-10 and OPS-301) and find operative strategies to improve efficiency and strategic means to ensure optimal documentation and coding quality. In a prospective study, documentation and coding quality were evaluated in a standardized way by weekly assessment. Clinical data from 1385 inpatients were processed for initial correctness and quality of documentation and coding. Principal diagnoses were found to be accurate in 82.7% of cases, inexact in 7.1%, and wrong in 10.1%. Effects on financial returns occurred in 16%. Based on these findings, an optimized, interdisciplinary, and multiprofessional workflow on medical documentation, coding, and data control was developed. Workflow incorporating regular assessment of documentation and coding quality is required by the DRG system to ensure efficient accounting of hospital services. Interdisciplinary and multiprofessional cooperation is recognized to be an important factor in establishing an efficient workflow in medical documentation and coding.

  3. Guidelines for the introduction of a quality assurance programme in a diagnostic imaging department

    International Nuclear Information System (INIS)

    1992-01-01

    Radiographers, whether they practice in the National Health Service (NHS) or other health care systems, always strive to deliver a high quality service for their patients. The profession and its members work hard to maintain and improve standards of patient care and technical accuracy. Why then does the College of Radiographers feel it necessary to publish Quality Assurance Guidelines? The answer lies in the greater awareness that the best possible service provision requires every part of the whole service to be performing as well as it possibly can. To be sure these individual parts are achieving this goal requires that we set standards for them and monitor and reassess them regularly. The quality of an individual's or a system's performance cannot be defined in absolute terms, although this is how many people would see it. There are too many variables, some of which cannot be controlled. Instead, we must define quality as the ability to perform the required task to set standards, given the prevailing conditions and existing resources. In radiography we can assure quality by being sure that those factors over which we have control are optimised. The College of Radiographers Working Party on Quality Assurance was formed in response to members' concerns about the requirements of professionalism and legislation with regard to quality assurance. Members were confused by the approach to quality management issues, standard setting, monitoring, evaluation and the required record keeping. Work began on a comprehensive publication centred on the quality assurance of radiographic processes. However, the College felt there was danger in following a well trodden path, particularly as the passing months saw the release of a series of related publications from various sources pre-emptying the efforts of the Working Party. Ultimately, the original remit was considered to hold greater promise - a set of guidelines for the quality management of the whole of our service delivery

  4. Evaluation of a laboratory quality assurance pilot programme for malaria diagnostics in low-transmission areas of Kenya, 2013.

    Science.gov (United States)

    Wanja, Elizabeth; Achilla, Rachel; Obare, Peter; Adeny, Rose; Moseti, Caroline; Otieno, Victor; Morang'a, Collins; Murigi, Ephantus; Nyamuni, John; Monthei, Derek R; Ogutu, Bernhards; Buff, Ann M

    2017-05-25

    One objective of the Kenya National Malaria Strategy 2009-2017 is scaling access to prompt diagnosis and effective treatment. In 2013, a quality assurance (QA) pilot was implemented to improve accuracy of malaria diagnostics at selected health facilities in low-transmission counties of Kenya. Trends in malaria diagnostic and QA indicator performance during the pilot are described. From June to December 2013, 28 QA officers provided on-the-job training and mentoring for malaria microscopy, malaria rapid diagnostic tests and laboratory QA/quality control (QC) practices over four 1-day visits at 83 health facilities. QA officers observed and recorded laboratory conditions and practices and cross-checked blood slides for malaria parasite presence, and a portion of cross-checked slides were confirmed by reference laboratories. Eighty (96%) facilities completed the pilot. Among 315 personnel at pilot initiation, 13% (n = 40) reported malaria diagnostics training within the previous 12 months. Slide positivity ranged from 3 to 7%. Compared to the reference laboratory, microscopy sensitivity ranged from 53 to 96% and positive predictive value from 39 to 53% for facility staff and from 60 to 96% and 52 to 80%, respectively, for QA officers. Compared to reference, specificity ranged from 88 to 98% and negative predictive value from 98 to 99% for health-facility personnel and from 93 to 99% and 99%, respectively, for QA officers. The kappa value ranged from 0.48-0.66 for facility staff and 0.57-0.84 for QA officers compared to reference. The only significant test performance improvement observed for facility staff was for specificity from 88% (95% CI 85-90%) to 98% (95% CI 97-99%). QA/QC practices, including use of positive-control slides, internal and external slide cross-checking and recording of QA/QC activities, all increased significantly across the pilot (p < 0.001). Reference material availability also increased significantly; availability of six microscopy job

  5. Near-Infrared Spectroscopic Screening for Bladder Disease in Africa: Training Rural Clinic Staff to Collect Data of Diagnostic Quality

    Directory of Open Access Journals (Sweden)

    Lynn Stothers

    2016-01-01

    Full Text Available Background. While near-infrared spectroscopy (NIRS has recognized relevance for developing countries, biomedical applications are rare. This reflects the cost and complexity of NIRS and the convention of comprehensive training for accurate data collection. In an international initiative using transcutaneous NIRS to screen for bladder disease in Africa, we evaluated if interactive training enabled clinic staff to collect data accurately. Methods. Workshop training in a Ugandan medical clinic on NIRS monitoring theory; bladder physiology and chromophore changes occurring with disease; device orientation; device positioning over the bladder, monitoring subjects during voiding; and saving/uploading data. Participation in patient screening followed with observation, assistance, and then data collection. Evaluation comprised conduct of serial independent screenings with analysis if saved files were of diagnostic quality. Results. 10 individuals attended 1-hour workshops and then 0.5–3.0 hours of screening. Five then felt able to conduct screening independently and all collected data were of diagnostic quality (>5 consecutive patients; all had participated in screening for >1.5 hours (6+ subjects; less participation allowed competent assistance but not consistent adherence to the monitoring protocol. Conclusion. A simplified NIRS system, small-group theory/orientation workshops, and >I.5 hours of 1 : 1 training during screening enabled clinic staff in Africa to collect accurate NIRS data.

  6. Chromatographic quality control procedures for /sup 99m/Tc-diagnostic agents

    International Nuclear Information System (INIS)

    Marinelli, M.; Pozzato, R.; Garuti, P.; Zucchini, G.L.

    1986-01-01

    The purpose of this work was to experiment simple and rapid chromatographic systems, based on paper and thin-layer techniques, to test the radiochemical purity of some common /sup 99m/Tc diagnostic agents, and select those systems able to prevent the anomalies due to oxidation and artifact production. The agents were examined under conditions which usually bring about the above mentioned anomalies, then the results were compared with those obtained under controlled conditions. Quali- and quantitative detection of the activity present on the chromatograms was carried out using the equipment available in nuclear medicine departments

  7. Quality assurance in diagnostic radiology; Garantia de qualidade em radiologia diagnostica

    Energy Technology Data Exchange (ETDEWEB)

    Furquim, Tania A.C. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Eletrotecnica e Energia], e-mail: tfurquim@iee.usp.br; Costa, Paulo R. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Fisica

    2009-10-15

    X-ray images provide important information for the establishment of a diagnosis, treatment and follow-up procedure. Then, the necessary level of image quality for correct diagnosis has to be obtained at the lowest possible radiation dose to the patient. These benefits could be achieved by the implementation of rigorous quality assurance program. As advances in digital technology allowed the fast development of different detectors for radiological applications, the transition from a screen-film system to a digital environment became a difficult matter, and this should be accomplished with an optimization of exposures and image quality. This paper aimed to review some of the new digital detectors and describe some issues associated with a quality assurance program dedicated to technologies like digital and computed radiography, digital mammography or computed tomography multislice. Thus, it is intended to emphasize that the increasing complexity of radiological equipment demands a new technical competence and that systematic continuing education of medical physicists is necessary. (author)

  8. External quality assessment of the molecular diagnostics and genotyping of meticillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    R. te Witt (René); A.F. van Belkum (Alex); W.G. MacKay (William); P.S. Wallace; W.B. van Leeuwen (Willem)

    2010-01-01

    textabstractTwo multicentre external quality assessments (EQA) for the molecular detection and genotyping of meticillin-resistant Staphylococcus aureus (MRSA) were arranged. Firstly, 11 samples containing various amounts of inactivated MRSA strains, meticillin-susceptible S. aureus (MSSA),

  9. Understanding why an active video game intervention did not improve motor skill and physical activity in children with developmental coordination disorder: A quantity or quality issue?

    Science.gov (United States)

    Howie, Erin K; Campbell, Amity C; Abbott, Rebecca A; Straker, Leon M

    2017-01-01

    Active video games (AVGs) have been identified as a novel strategy to improve motor skill and physical activity in clinical populations. A recent cross-over randomized trial found AVGs to be ineffective at improving motor skill and physical activity in the home-environment for children with or at-risk for developmental coordination disorder (DCD). The study purpose was to better understand why the intervention had been ineffective by examining the quantity and quality of AVG play during an AVG intervention for children with or at-risk for DCD. Participants (n=21, ages 9-12) completed the 16 week AVG intervention. Detailed quantitative and qualitative data were systematically triangulated to obtain the quantity of exposure (AVG exposure over time, patterns of exposure) and quality of use (game selection, facilitators and barriers to play). The median AVG dose (range 30-35min/day) remained relatively stable across the intervention and met the prescribed dose. Play quality was impacted by game selection, difficulty playing games, lack of time, illness, technical difficulties and boredom. The ineffectiveness of a home-based AVG intervention may be due to quality of play. Strategies to improve the quality of game play may help realize the potential benefits of AVGs as a clinical tool for children with DCD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. The Extended-OPQ Method for User-Centered Quality of Experience Evaluation: A Study for Mobile 3D Video Broadcasting over DVB-H

    Directory of Open Access Journals (Sweden)

    Jumisko-Pyykkö Satu

    2011-01-01

    Full Text Available Abstract The Open Profiling of Quality (OPQ is a mixed methods approach combining a conventional quantitative psychoperceptual evaluation and qualitative descriptive quality evaluation based on naïve participants' individual vocabulary. The method targets evaluation of heterogeneous and multimodal stimulus material. The current OPQ data collection procedure provides a rich pool of data, but full benefit of it has neither been taken in the analysis to build up completeness in understanding the phenomenon under the study nor has the procedure in the analysis been probed with alternative methods. The goal of this paper is to extend the original OPQ method with advanced research methods that have become popular in related research and the component model to be able to generalize individual attributes into a terminology of Quality of Experience. We conduct an extensive subjective quality evaluation study for 3D video on mobile device with heterogeneous stimuli. We vary factors on content, media (coding, concealments, and slice modes, and transmission levels (channel loss rate. The results showed that advanced procedures in the analysis cannot only complement each other but also draw deeper understanding on Quality of Experience.

  11. Internal quality control of PCR-based genotyping methods in research studies and patient diagnostics

    DEFF Research Database (Denmark)

    Bladbjerg, Else-Marie; Gram, Jørgen; Jespersen, Jørgen

    2002-01-01

    -isolation (pre-analytical factors), DNA-amplification, digestion with restriction enzymes, electrophoresis (analytical factors), result reading and entry into a database (post-analytical factors). Furthermore, we evaluated a procedure for result confirmation. Isolated DNA was of good quality (42 microg/ml blood....... Control of data handling revealed 0.1% reading mistakes and 0.5% entry mistakes. Based on our experiences we propose an internal quality control programme for widely used PCR-based haemostasis polymorphism analyses....

  12. External quality assessment for arbovirus diagnostics in the World Health Organization Western Pacific Region, 2013–2016: improving laboratory quality over the years

    Science.gov (United States)

    Abdad, Mohammad Yazid; Squires, Raynal C; Cognat, Sebastien; Oxenford, Christopher John

    2017-01-01

    Arboviruses continue to pose serious public health threats in the World Health Organization (WHO) Western Pacific Region. As such, laboratories need to be equipped for their accurate detection. In 2011, to ensure test proficiency, the WHO Regional Office for the Western Pacific piloted an external quality assessment (EQA) programme for arbovirus diagnostics. By 2016, it had grown into a global programme with participation of 96 laboratories worldwide, including 25 laboratories from 19 countries, territories and areas in the Region. The test performance of the 25 laboratories in the Region in 2016 was high with 23 (92%) reporting correct results in all specimens for dengue and chikungunya viruses. For Zika virus, 18 (72%) of the 25 laboratories reported correct results in all specimens, while seven (28%) demonstrated at least one error. When comparing iterations of this EQA programme in the Region between 2013 and 2016, the number of participating laboratories increased from 18 to 25. The first round only included dengue virus, while the latest round additionally included chikungunya, Zika and yellow fever viruses. Proficiency for molecular detection of dengue virus remained high (83–94%) over the four-year period. The observed proficiency for arbovirus diagnostics between 2013 and 2016 is an indicator of laboratory quality improvement in the Region. PMID:29051839

  13. External quality assessment for arbovirus diagnostics in the World Health Organization Western Pacific Region, 2013–2016: improving laboratory quality over the years

    Directory of Open Access Journals (Sweden)

    Mohammad Yazid Abdad

    2017-09-01

    Full Text Available Arboviruses continue to pose serious public health threats in the World Health Organization (WHO Western Pacific Region. As such, laboratories need to be equipped for their accurate detection. In 2011, to ensure test proficiency, the WHO Regional Office for the Western Pacific piloted an external quality assessment (EQA programme for arbovirus diagnostics. By 2016, it had grown into a global programme with participation of 96 laboratories worldwide, including 25 laboratories from 19 countries, territories and areas in the Region. The test performance of the 25 laboratories in the Region in 2016 was high with 23 (92% reporting correct results in all specimens for dengue and chikungunya viruses. For Zika virus, 18 (72% of the 25 laboratories reported correct results in all specimens, while seven (28% demonstrated at least one error. When comparing iterations of this EQA programme in the Region between 2013 and 2016, the number of participating laboratories increased from 18 to 25. The first round only included dengue virus, while the latest round additionally included chikungunya, Zika and yellow fever viruses. Proficiency for molecular detection of dengue virus remained high (83–94% over the four-year period. The observed proficiency for arbovirus diagnostics between 2013 and 2016 is an indicator of laboratory quality improvement in the Region.

  14. Bronchial blocker versus left double-lumen endotracheal tube in video-assisted thoracoscopic surgery: a randomized-controlled trial examining time and quality of lung deflation.

    Science.gov (United States)

    Bussières, Jean S; Somma, Jacques; Del Castillo, José Luis Carrasco; Lemieux, Jérôme; Conti, Massimo; Ugalde, Paula A; Gagné, Nathalie; Lacasse, Yves

    2016-07-01

    Double-lumen endotracheal tubes (DL-ETT) and bronchial blockers (BB) have both been used for lung isolation in video-assisted thoracic surgery (VATS). Though not well studied, it is widely thought that a DL-ETT provides faster and better quality lung collapse. The aim of this study was to compare a BB technique vs a left-sided DL-ETT strategy with regard to the time and quality of lung collapse during one-lung ventilation (OLV) for elective VATS. Forty patients requiring OLV for VATS were randomized to receive a BB (n = 20) or a left-sided DL-ETT (n = 20). The primary endpoint was the time from pleural opening (performed by the surgeon) until complete lung collapse. The time was evaluated offline by reviewing video recorded during the VATS. The quality of lung deflation was also graded offline using a visual scale (1 = no lung collapse; 2 = partial lung collapse; and 3 = total lung collapse) and was recorded at several time points after pleural incision. The surgeon also graded the time to complete lung collapse and quality of lung deflation during the procedure. The surgeon's guess as to which device was used for lung isolation was also recorded. Of the 40 patients enrolled in the study, 20 patients in the DL-ETT group and 18 in the BB group were analyzed. There mean (standard deviation) time to complete lung collapse of the operative lung was significantly faster using the BB compared with using the DL-ETT [7.5 (3.8) min vs 36.6 (29.1) min, respectively; mean difference, 29.1 min; 95% confidence interval, 1.8 to 7.2; P < 0.001]. Overall, a higher proportion of patients in the BB group than in the DL-ETT group achieved a quality of lung collapse score of 3 at five minutes (57% vs 6%, respectively; P < 0.004), ten minutes (73% vs 14%, respectively; P = 0.005), and 20 min (100% vs 25%, respectively; P = 0.002) after opening the pleura. The surgeon incorrectly guessed the type of device used in 78% of the BB group and 50% of the DL-ETT group (P = 0.10). The time and

  15. A European Quality Control Programme as a cooperative tool between users and a diagnostic company.

    Science.gov (United States)

    Costongs, G M; Janson, P C

    1993-12-01

    Achievement of appropriate precision is a major challenge for the clinical laboratory, particularly in specialized fields such as enzymology and immunochemistry. Especially in immunochemistry, where accuracy can only poorly be checked because of a lack of reference methods and a multitude of detectable epitopes, precision remains an important index of quality. In immunochemical methods there are three main sources of variation: differences in methodology, lot-to-lot variation and performance of the assay, the latter including the skill of the technicians and instrument performance. The results of a European Quality Control Programme for the users of one type of automated immunoassay analyser were compared with a similar Italian Quality Control Programme for users of different immunometric techniques. The precisions (%CV) of the two programmes were compared, as well as the number of values lying within one half of the biological variation of the analysed serum components. Feedback between users and manufacturers leads to a clear improvement in analysis performance, so that most of the considered values come to lie within the acceptable limits of 1/2 of the biological variation. It is concluded that both national and international quality control programmes are very useful for indicating the intrinsic quality of the quantities used in the clinical laboratory.

  16. Quality control assessment of diagnostic x-ray facilities in Ghana

    International Nuclear Information System (INIS)

    Amoako, J.K.; Charles, D.F.; Oppong-Adu, C.; Schandorf, C.

    2009-01-01

    Twenty-three X-ray machines located at 20 different hospitals in Ghana were assessed for quality assurance and control. The radiographic parameters evaluated were tube voltage and current, tube output consistency variation with kilovoltage (kV) and current-time (mAs) factor, exposure time accuracy and beam quality as measured by half-value layer. The photographic parameters assessed were type of films, level of film fogging, film speed, contrast index and film processing temperature. Twenty two of the machines were ∼ 99 % output consistency with standard kVp and mAs. Twelve of the machines had output linearity deviation of less than the acceptable 5 %, while 22 machines were within the accepted kVp deviation of 5 %. The film processing temperature at most hospitals exceeded the required level, due to the absence of air conditioners in the darkrooms. The darkroom quality control at all the facilities was very high. Fogging of films was minimal as indicated by the Base + Fog value of 0.3, speed index of film was ∼ 1.65 and contrast index was comparable to the acceptable value of 1.5. The level of timer accuracy was greater than 95 % for all the X-ray machines with the exception of one. The general quality control status of all the X-ray machines and darkrooms assessed were acceptable and within the quality assurance standards. (au)

  17. Quality control: a measure for optimization of dose in diagnostic radiology

    International Nuclear Information System (INIS)

    Abd Aziz Mhd Ramli; Muhammad Jamal Md Isa; Husaini Salleh

    2002-01-01

    Patient dose should always be a factor that is taken into account when using diagnostic X-ray equipment. There is no doubt that patients receive vastly different radiation doses for same examination under different circumstances and performance as well as safety standard of X-ray generating machine is one of the possible causes for this. MINT's experience in measuring performance and safety standard of X-ray fluoroscopic equipments in the year of 2000 indicated that 70% of the irradiating apparatus tend to deliver unnecessary exposures to patients due to various causes. Improper calibration and the usage of unoptimized fluoroscopic X-ray equipment are identified as two major causes that lead to unoptimized medical exposures to patient

  18. Use of Video Podcasts to Communicate Scientific Findings to Non-Scientists— Examples from the U.S. Geological Survey National Water-Quality Assessment Program

    Science.gov (United States)

    Harned, D. A.; McMahon, G.; Capelli, K.

    2010-12-01

    The U.S Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) provides information about (1) water-quality conditions and how those conditions vary locally, regionally, and nationally, (2) water-quality trends, and (3) factors that affect those conditions. As part of the NAWQA Program, the Effects of Urbanization on Stream Ecosystems (EUSE) study examined the vulnerability and resilience of streams to urbanization. Completion of the EUSE study has resulted in over 20 scientific publications. Video podcasts are being used to communicate the relevance of these scientific findings to resource managers and the general public. Two video podcasts have been produced to date (9-1-2010). The first film “Effects of Urbanization on Stream Ecosystems” is a 3-minute summary of results of the EUSE study. The film is accessible on the USGS Corecast website (http://www.usgs.gov/corecast/details.asp?ep=127) and is available in MPG, WMV, and QuickTime formats, as an audio-only podcast, with a complete transcript of the film; and as a YouTube video (http://www.youtube.com/watch?v=BYwZiiORYG8) with subtitles. The film has been viewed over 6200 times, with most downloads occurring in the first 3 weeks after the June release. Views of the film declined to approximately 60 a week for the following 9 weeks. Most of the requests for the film have originated from U.S. domain addresses with 13 percent originating from international addresses. The film was posted on YouTube in June and has received 262 views since that time. A 15-minute version of the film with more technical content is also available for access from the EUSE website (http://water.usgs.gov/nawqa/urban/html/podcasts.html). It has been downloaded over 660 times. The bulk of the requests occurred in the first 2 weeks after release, with most requests originating from U.S. addresses and 11 percent originating internationally. In the second film “Stormwater, Impervious Surface, and Stream Health” (not

  19. Local Audit of Diagnostic Surgical Pathology as a Tool for Quality ...

    African Journals Online (AJOL)

    Background: Internal audit has been rarely done for quality assurance of histology laboratories in Nigeria. We reviewed the steps involved in the production of reports with a view to assessing the performance of the histopathology laboratory of Aminu Kano Teaching Hospital, Nigeria. Methods: A randomly selected 2 per ...

  20. Film reject analysis and image quality in diagnostic Radiology Department of a Teaching hospital in Ghana

    Directory of Open Access Journals (Sweden)

    J. Owusu-Banahene

    2014-10-01

    Full Text Available Patients usually undergo repeated X-ray examinations after their initial X-ray radiographs are rejected due to poor image quality. This subjects the patients to an excess radiation exposure and extra cost and necessitates the need to investigate the causes of reject. The use of reject analysis as part of the overall quality assurance programs in clinical radiography and radiology services is vital in the evaluation of image quality of a well-established practice. It is shown that, in spite of good quality control maintained by the Radiology Department of a Teaching hospital in Ghana, reject analysis performed on a number of radiographic films developed indicated 14.1% reject rate against 85.9% accepted films. The highest reject rate was 57.1 ± 0.7% which occurs in cervical spine and the lowest was7.7 ± 0.5% for lumbar spine. The major factors contributing to film rejection were found to be over exposure and patient positioning in cervical spine examinations. The most frequent examination was chest X-ray which accounts for about 42.2% of the total examinations. The results show low reject rates by considering the factors for radiographic rejection analysis in relation to both equipment functionality and film development in the facility.

  1. Correlation between the physical performances measured from detectors and the diagnostic image quality in digital mammography

    International Nuclear Information System (INIS)

    Perez-Ponce, H.

    2009-05-01

    In digital mammography two approaches exist to estimate image quality. In the first approach, human observer assesses the lesion detection in mammograms. Unfortunately, such quality assessment is subject to interobserver variability, and requires a large amount of time and human resources. In the second approach, objective and human-independent parameters relating to image spatial resolution and noise (MTF and NPS) are used to evaluate digital detector performance; even if these parameters are objective, they are not directly related to lesion detection. A method leading to image quality assessment which is both human independent, and directly related to lesion detection is very important for the optimal use of mammographic units. This Ph.D thesis presents the steps towards such a method: the computation of realistic virtual images using an 'X ray source/digital detector' model taking into account the physical parameters of the detector (spatial resolution and noise measurements) measured under clinical conditions. From results obtained in this work, we have contributed to establish the link between the physical characteristics of detectors and the clinical quality of the image for usual exposition conditions. Furthermore, we suggest the use of our model for the creation of virtual images, in order to rapidly determine the optimal conditions in mammography, which usually is a long and tedious experimental process. This is an essential aspect to be taken into account for radioprotection of patients, especially in the context of organized mass screening of breast cancer. (author)

  2. Internal quality assurance in diagnostic microbiology: A simple approach for insightful data.

    Science.gov (United States)

    Scherz, Valentin; Durussel, Christian; Greub, Gilbert

    2017-01-01

    Given the importance of microbiology results on patient care, high quality standards are expected. Internal quality assurance (IQA) could mitigate the limitations of internal quality control, competency assessment and external quality assurance, adding a longitudinal insight, including pre- and post-analytical steps. Here, we implemented an IQA program in our clinical microbiology facilities with blind resubmission of routine samples during 22 months. One-hundred-and-twenty-one out of 123 (98.4%) serological analyses and 112 out of 122 (91.8%) molecular analyses were concordant. Among the discordances in molecular biology analyses, 6 results were low positive samples that turned out negative, likely due to stochastic repartition of nucleic acids. Moreover, one identified retranscription error led us to implement automated results transmission from the Applied Biosystems instruments to the laboratory information system (LIS). Regarding Gram stain microscopy, 560 out of 745 (75.2%) of compared parameters were concordant. As many as 67 out of 84 (79.8%) pairs of culture results were similar, including 16 sterile pairs, 27 having identical identification or description and semi-quantification and 24 only showing variations in semi-quantification with identical description or identification of colonies. Seventeen pairs had diverging identification or description of colonies. Culture was twice only done for one member of the pairs. Regarding antibiotic susceptibility testing, a major discrepancy was observed in 5 out of 48 results (10.4%). In conclusion, serological tests were highly reproducible. Molecular diagnosis also revealed to be robust except when the amounts of nucleic acids present in the sample were close to the limits of detection. Conventional microbiology was less robust with major discrepancies reaching 39.5% of the samples for microscopy. Similarly, culture and antibiotic susceptibility testing were prone to discrepancies. This work was ground for

  3. A new perceptual difference model for diagnostically relevant quantitative image quality evaluation: a preliminary study.

    Science.gov (United States)

    Miao, Jun; Huang, Feng; Narayan, Sreenath; Wilson, David L

    2013-05-01

    Most objective image quality metrics average over a wide range of image degradations. However, human clinicians demonstrate bias toward different types of artifacts. Here, we aim to create a perceptual difference model based on Case-PDM that mimics the preference of human observers toward different artifacts. We measured artifact disturbance to observers and calibrated the novel perceptual difference model (PDM). To tune the new model, which we call Artifact-PDM, degradations were synthetically added to three healthy brain MR data sets. Four types of artifacts (noise, blur, aliasing or "oil painting" which shows up as flattened, over-smoothened regions) of standard compressed sensing (CS) reconstruction, within a reasonable range of artifact severity, as measured by both PDM and visual inspection, were considered. After the model parameters were tuned by each synthetic image, we used a functional measurement theory pair-comparison experiment to measure the disturbance of each artifact to human observers and determine the weights of each artifact's PDM score. To validate Artifact-PDM, human ratings obtained from a Double Stimulus Continuous Quality Scale experiment were compared to the model for noise, blur, aliasing, oil painting and overall qualities using a large set of CS-reconstructed MR images of varying quality. Finally, we used this new approach to compare CS to GRAPPA, a parallel MRI reconstruction algorithm. We found that, for the same Artifact-PDM score, the human observer found incoherent aliasing to be the most disturbing and noise the least. Artifact-PDM results were highly correlated to human observers in both experiments. Optimized CS reconstruction quality compared favorably to GRAPPA's for the same sampling ratio. We conclude our novel metric can faithfully represent human observer artifact evaluation and can be useful in evaluating CS and GRAPPA reconstruction algorithms, especially in studying artifact trade-offs. Copyright © 2013 Elsevier Inc

  4. Comparing apples and oranges: assessment of the relative video quality in the presence of different types of distortions

    DEFF Research Database (Denmark)

    Reiter, Ulrich; Korhonen, Jari; You, Junyong

    2011-01-01

    well different objective quality metrics estimate the relative subjective quality levels for content with different types of quality distortions. Our conclusion is that none of the studied objective metrics works reliably for assessing the co-impact of compression artifacts and transmission errors...... on the subjective quality. Nevertheless, we have observed that the objective metrics' tendency to either over- or underestimate the perceived impact of transmission errors has a high correlation with the spatial and temporal activity levels of the content. Therefore, our results can be useful for improving...

  5. Radiation safety and quality assurance in diagnostic x-ray imaging 1999

    International Nuclear Information System (INIS)

    Servonmaa, A.

    1999-04-01

    In the European Union, the Directive 97/43/Euratom concerning the medical use of radiation brings many new tasks to radiation users. Quality assurance, patient dose measurement, staff training and clinical audit are among the most essential of these tasks. The Finnish radiation legislation has been modified to comply with the Directive. Much work is still required for practical implementation of these rules. This report deals with applications of the medical radiation Directive. Most applications are still at the planning stage, and clear guidance is lacking. However, the users have to know in time about these plans and future duties concerning them. Experience on quality assurance and clinical audit in hospitals are especially valuable in providing practical information on benefits and problems of these practices. Other radiation related topics, such as radiation risks, radioactivity in foods, and use of radiation in other European countries, are also included in the report. (orig.)

  6. Radiation safety and quality in diagnostic x-ray imaging 2001; Saeteilyturvallisuus ja laatu roentgendiagnostiikassa 2001

    Energy Technology Data Exchange (ETDEWEB)

    Servomaa, A.; Parviainen, T. (eds.)

    2001-05-01

    The obligations of the medical exposure directive (97/43/Euratom) for hospitals dominate the current activities in radiation protection in medical radiology. The directive gives special emphasis to radiation exposure of children, to examinations with high radiation doses and to radiation exposure in health screening programmes. The most important examinations with high doses are radiological interventions, where even acute skin effects are possible, and the computed tomography where the number of CT examinations makes only about 5% from the total number of x-ray examinations but the collective effective dose about 40% from the combined collective effective dose of all x-ray examinations. In the research projects financed by the European Commission, radiation exposures to paediatric patients have been measured in radiography, fluoroscopy and CT, and various dose assessment methods have been compared to develop a method for national follow-up of patients' radiation dose. The newest research project is focused on dosimetry and quality assurance in interventional radiology and digital imaging. Other actual topics are the development of radiation protection regulations and quality systems, education and training programmes, and clinical audits. This report deals with new radiation protection guides and recommendations and the education and training of radiological staff in radiation protection. One important topic is the development of national follow-up method of radiation exposure to patients and comparison of various dose assessment methods. Quality assurance in health care and in paediatric radiology, and the acceptance test and quality assurance measurements of radiological equipment are also described. (orig.)

  7. Video game addiction: The push to pathologize video games

    DEFF Research Database (Denmark)

    Nielsen, Rune Kristian Lundedal; Ferguson, Christopher; Bean, Anthony

    2017-01-01

    With proposals to include “gaming disorder” in both the Diagnostic and Statistical Manual (DSM) and International Compendium of Diseases (ICD), the concept of video game addiction has gained traction. However, many aspects of this concept remain controversial. At present, little clarity has been...... achieved regarding diagnostic criteria and appropriate symptoms. It is unclear if symptoms that involve problematic video gaming behavior should be reified as a new disorder, or are the expression of underlying mental conditions. Nonetheless, the recent proposals around gaming disorder from respected...... and necessity of the overarching construct. This raises multiple concerns. First, the current approaches to understanding “gaming addiction” are rooted in substance abuse research and approaches do not necessarily translate to media consumption. Second, some research has indicated that “video game addiction...

  8. Obese patients in an open MRI at 1.0 Tesla: image quality, diagnostic impact and feasibility

    International Nuclear Information System (INIS)

    Bucourt, Maximilian de; Streitparth, Florian; Wonneberger, Uta; Rump, Jens; Teichgraeber, Ulf

    2011-01-01

    To investigate the performance of an open MRI system at its conceptual limits by examining excessively obese patients who otherwise could not receive adequate imaging examinations. Twenty-six excessively obese patients (BMI ≥ 35, average age 46) where CT, standard MR or ultrasound examinations were not possible or not conclusive were referred to an open MRI system at 1.0 Tesla. Image quality was measured by SNR and CNR with the integrated body coil for obese patients and optimal body coils for a regular weight control group (average BMI 23, average age 30). MRI findings were evaluated by a diagnostic impact matrix. SNR and CNR were generally lower in obese patients when the integrated body coil was used compared to the normal weight group with ideal body coils e.g.: For cerebral imaging T2W TSE (<5% for white matter, ca. 30% for grey matter) and T1W SE (ca. 15% for white matter, <5% for grey matter), for spinal imaging T2W TSE (ca. 35% for disc and vertebral body) and T1W SE (about 2% for disc, ca. 10% for vertebral body). Relevant new diagnoses impacting patient's therapy were identified in 30% (8/26), the particular medical question of the referring physician could be ruled out as possible reason for the medical condition in 53% (14/26). In excessively obese patients where CT, standard MR or ultrasound examination is not possible or not conclusive open MRI system have great potential in diagnostic evaluation, offering lower but sufficient image quality to impact therapy. (orig.)

  9. APPLICABILITY ANALYSIS OF THE PHASE CORRELATION ALGORITHM FOR STABILIZATION OF VIDEO FRAMES SEQUENCES FOR CAPILLARY BLOOD FLOW

    Directory of Open Access Journals (Sweden)

    K. A. Karimov

    2016-05-01

    Full Text Available Videocapillaroscopy is a convenient and non-invasive method of blood flow parameters recovery in the capillaries. Capillaries position can vary at recorded video sequences due to the registration features of capillary blood flow. Stabilization algorithm of video capillary blood flow based on phase correlation is proposed and researched. This algorithm is compared to the known algorithms of video frames stabilization with full-frame superposition and with key points. Programs, based on discussed algorithms, are compared under processing the experimentally recorded video sequences of human capillaries and under processing of computer-simulated sequences of video frames with the specified offset. The full-frame superposition algorithm provides high quality of stabilization; however, the program based on this algorithm requires significant computational resources. Software implementation of the algorithm based on the detection of the key points is characterized by good performance, but provides low quality of stabilization for video sequences capillary blood flow. Algorithm based on phase correlation method provides high quality of stabilization and program realization of this algorithm requires minimal computational resources. It is shown that the phase correlation algorithm is the most useful for stabilization of video sequences for capillaries blood flow. Obtained findings can be used in the software for biomedical diagnostics.

  10. Significant dose reduction is feasible in FDG PET/CT protocols without compromising diagnostic quality.

    Science.gov (United States)

    Prieto, Elena; García-Velloso, María José; Rodríguez-Fraile, Macarena; Morán, Verónica; García-García, Berta; Guillén, Fernando; Morales, María Isabel; Sancho, Lidia; Peñuelas, Iván; Richter, José Ángel; Martí-Climent, Josep María

    2018-02-01

    To reduce the radiation dose to patients by optimizing oncological FDG PET/CT protocols. The baseline PET/CT protocol in our institution for oncological PET/CT examinations consisted of the administration of 5.18 MBq/kg of FDG and a CT acquisition with a reference current-time product of 120 mAs. In 2016, FDG activity was reduced to 4.44 and 3.70 MBq/kg and reference CT current-time-product was reduced to 100 and 80 mAs. 322 patients scanned with different protocols were retrospectively evaluated. For each patient, effective dose was calculated. The overall image quality was subjectively rated by the referring physician on a 4-point scale (IQ score: 1 excellent, 2 good, 3 poor but interpretable, 4 poor not interpretable). Image quality was quantitatively evaluated measuring noise in the liver. CT Results: Effective dose was progressively reduced from 9.5 ± 2.8 to 8.0 ± 2.3 and 6.2 ± 1.5 mSv (p dose reduction of 34.9% was achieved. There was a significant degradation of IQ score (p 2) did not increase. PET Results: Effective dose was gradually reduced from 6.5 ± 1.4 to 5.7 ± 1.3 and 5.0 ± 1.0 mSv (p dose reduction was 23.4%. IQ score (p dose reduction of 28.7% was reached. Despite a slight reduction in image quality, the new regime was successfully implemented with readers reporting unchanged clinical confidence. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  11. Digital Subtraction Fluoroscopic System With Tandem Video Processing Units

    Science.gov (United States)

    Gould, Robert G.; Lipton, Martin J.; Mengers, Paul; Dahlberg, Roger

    1981-07-01

    A real-time digital fluoroscopic system utilizing two video processing units (Quantex) in tandem to produce continuous subtraction images of peripheral and internal vessels following intravenous contrast media injection has been inves-tigated. The first processor subtracts a mask image consisting of an exponentially weighted moving average of N1 frames (N1 = 2k where k = 0.7) from each incoming video frame, divides by N1, and outputs the resulting difference image to the second processor. The second unit continuously averages N2 incoming frames (N2 = 2k) and outputs to a video monitor and analog disc recorder. The contrast of the subtracted images can be manipulated by changing gain or by a non-linear output transform. After initial equipment adjustments, a subtraction sequence can be produced without operator interaction with the processors. Alternatively, the operator can freeze the mask and/or the subtracted output image at any time during the sequence. Raw data is preserved on a wide band video tape recorder permitting retrospective viewing of an injection sequence with different processor settings. The advantage of the tandem arrangement is that it has great flexibility in varying the duration and the time of both the mask and injection images thereby minimizing problems of registration between them. In addition, image noise is reduced by compiling video frames rather than by using a large radiation dose for a single frame, which requires a wide dynamic range video camera riot commonly available in diagnostic x-ray equipment. High quality subtraction images of arteries have been obtained in 15 anesthetized dogs using relatively low exposure rates (10-12 μR/video frame) modest volumes of contrast medium (0.5-1 ml/kg), and low injection flow rates (6-10 ml/sec). The results/ achieved so far suggest that this system has direct clinical applications.

  12. Spectra transmitted by mortar barite in X-Ray qualities applied in diagnostic radiology as shielding

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Junior, Airton T., E-mail: airton.almeida@fundacentro.gov.br [Fundacaoo Jorge Duprat Figueiredo de Seguranca e Medicina do Trabalho (FUNDACENTRO), Belo Horizonte, MG (Brazil); Araujo, F.G.S. [Universidade Federal de Ouro Preto (REDEMAT/UFOP), MG (Brazil); Nogueira, M.S., E-mail: mnogue@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Santos, M.A.P. [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2015-07-01

    Concrete which contains water, cement and aggregate, is widely used in building construction such as medical hospitals. The CdZnTe spectrometry system was used to acquire the transmitted spectra in the RQR qualities and the stripping procedure was performed by taking into account both the contributions of efficiency and x-ray escape fraction, experimentally determined. The samples were prepared in rectangular plate format with dimensions of (5 x 5) cm with thicknesses varying from 0.2cm to 2cm and exposed to x-ray beams generated. The HVL and the mean energy in this energy range was determined. (author)

  13. Diagnosing common bile duct obstruction: comparison of image quality and diagnostic performance of three-dimensional magnetic resonance cholangiopancreatography with and without compressed sensing.

    Science.gov (United States)

    Kwon, Heejin; Reid, Scott; Kim, Dongeun; Lee, Sangyun; Cho, Jinhan; Oh, Jongyeong

    2018-01-04

    This study aimed to evaluate image quality and diagnostic performance of a recently developed navigated three-dimensional magnetic resonance cholangiopancreatography (3D-MRCP) with compressed sensing (CS) based on parallel imaging (PI) and conventional 3D-MRCP with PI only in patients with abnormal bile duct dilatation. This institutional review board-approved study included 45 consecutive patients [non-malignant common bile duct lesions (n = 21) and malignant common bile duct lesions (n = 24)] who underwent MRCP of the abdomen to evaluate bile duct dilatation. All patients were imaged at 3T (MR 750, GE Healthcare, Waukesha, WI) including two kinds of 3D-MRCP using 352 × 288 matrices with and without CS based on PI. Two radiologists independently and blindly assessed randomized images. CS acceleration reduced the acquisition time on average 5 min and 6 s to a total of 2 min and 56 s. The all CS cine image quality was significantly higher than standard cine MR image for all quantitative measurements. Diagnostic accuracy for benign and malignant lesions is statistically different between standard and CS 3D-MRCP. Total image quality and diagnostic accuracy at biliary obstruction evaluation demonstrates that CS-accelerated 3D-MRCP sequences can provide superior quality of diagnostic information in 42.5% less time. This has the potential to reduce motion-related artifacts and improve diagnostic efficacy.

  14. A multiplex two-color real-time PCR method for quality-controlled molecular diagnostic testing of FFPE samples.

    Directory of Open Access Journals (Sweden)

    Jiyoun Yeo

    Full Text Available Reverse transcription quantitative real-time PCR (RT-qPCR tests support personalized cancer treatment through more clinically meaningful diagnosis. However, samples obtained through standard clinical pathology procedures are formalin-fixed, paraffin-embedded (FFPE and yield small samples with low integrity RNA containing PCR interfering substances. RT-qPCR tests able to assess FFPE samples with quality control and inter-laboratory reproducibility are needed.We developed an RT-qPCR method by which 1 each gene was measured relative to a known number of its respective competitive internal standard molecules to control for interfering substances, 2 two-color fluorometric hydrolysis probes enabled analysis on a real-time platform, 3 external standards controlled for variation in probe fluorescence intensity, and 4 pre-amplification maximized signal from FFPE RNA samples. Reagents were developed for four genes comprised by a previously reported lung cancer diagnostic test (LCDT then subjected to analytical validation using synthetic native templates as test articles to assess linearity, signal-to-analyte response, lower detection threshold, imprecision and accuracy. Fitness of this method and these reagents for clinical testing was assessed in FFPE normal (N = 10 and malignant (N = 10 lung samples.Reagents for each of four genes, MYC, E2F1, CDKN1A and ACTB comprised by the LCDT had acceptable linearity (R(2>0.99, signal-to-analyte response (slope 1.0 ± 0.05, lower detection threshold (<10 molecules and imprecision (CV <20%. Poisson analysis confirmed accuracy of internal standard concentrations. Internal standards controlled for experimentally introduced interference, prevented false-negatives and enabled pre-amplification to increase signal without altering measured values. In the fitness for purpose testing of this two-color fluorometric LCDT using surgical FFPE samples, the diagnostic accuracy was 93% which was similar to that previously reported

  15. A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: comparison of image quality and diagnostic performance.

    Science.gov (United States)

    Ahn, Hye Shin; Kim, Sun Mi; Jang, Mijung; Yun, Bo La; Kim, Bohyoung; Ko, Eun Sook; Han, Boo-Kyung; Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung; Choi, Hye Young

    2014-01-01

    To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige®), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of "Mammogram enhancement ver. 2.0"; group B (SMB), specimen mammography with application of "Mammogram enhancement ver. 2.0". Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

  16. Diagnostic yield of 335 push video-enteroscopies Rendimiento diagnóstico de 355 videoenteroscopias por pulsión

    Directory of Open Access Journals (Sweden)

    B. J. Gómez Rodríguez

    2006-02-01

    Full Text Available Background and objectives: the diagnostic yield of push enteroscopy (PE varies widely from 13 to 78% of cases, according to the various series. The aim of this retrospective cohort study was to determine the endoscopic and histological yield of PE in our health area. Patients and methods: a total of 355 consecutive patients (190 males/165 females; mean age 45 years, range 15-89 underwent PE over a 6-year period, from 1997 to 2003. PE was performed under sedation and without overtube. Small-bowel mucosa biopsies were taken in 199 explorations (56%. Clinical indications for PE included: chronic diarrhea (35%, occult digestive bleeding (ODB or iron-deficiency anemia (28%, suspected small-bowel malignancy (16%, chronic abdominal pain (28/355; 8%, follow-up of polyposis or malabsorption syndromes (7%, and abnormal radiographic findings (6%. Results: PE detected lesions in 122 cases (34%; in 6 cases (6% lesions were within the reach of esophagogastroduodenoscopy. A normal macroscopic appearance of the small intestinal mucosa with an abnormal histological study was seen in 16 patients (6%. Major findings included: malabsorptive diseases (14%, nonspecific enteropathy (5%, angiodysplasia (3,5%, lymphangiectasia (3%; jejunal polyps (2%, Crohn's disease (2%, intestinal tumors (2%, extrinsic jejunal strictures (0.5%, and other (10/355; 3%. Abnormal radiographic findings (62%, chronic diarrhea (37% and ODB (31% were the indications with a higher diagnostic yield. No major complications were seen. Conclusions: according to our experience, PE is a safe and useful tool for the evaluation of small-bowel disease, especially in some indications (abnormal radiographic findings, chronic diarrhea, and ODB. Small-bowel biopsy increases PE's diagnostic yield in patients with chronic diarrhea.Introducción y objetivos: el rendimiento diagnóstico de la enteroscopia por pulsión (EP varía ampliamente (13-78% según las series. El objetivo de este estudio retrospectivo

  17. Deep video deblurring

    KAUST Repository

    Su, Shuochen

    2016-11-25

    Motion blur from camera shake is a major problem in videos captured by hand-held devices. Unlike single-image deblurring, video-based approaches can take advantage of the abundant information that exists across neighboring frames. As a result the best performing methods rely on aligning nearby frames. However, aligning images is a computationally expensive and fragile procedure, and methods that aggregate information must therefore be able to identify which regions have been accurately aligned and which have not, a task which requires high level scene understanding. In this work, we introduce a deep learning solution to video deblurring, where a CNN is trained end-to-end to learn how to accumulate information across frames. To train this network, we collected a dataset of real videos recorded with a high framerate camera, which we use to generate synthetic motion blur for supervision. We show that the features learned from this dataset extend to deblurring motion blur that arises due to camera shake in a wide range of videos, and compare the quality of results to a number of other baselines.

  18. Evaluation of quality assurance of some diagnostic x-ray machines in Khartoum state

    International Nuclear Information System (INIS)

    Mohammed, Sirelkatim Khogali

    2013-04-01

    Availability and the use of x-ray equipment in both private and government hospitals are on the increase today in Khartoum state. Quality control of such equipment is of particular importance to prevent avoidable high doses, radiation leakages and to ensure dose optimization. The results of quality control in this study indicated that: all centers were within the k Vp reproducibility level (5%). At k Vp 50 and 60 there were 93% of centers within the limit and 7% were out. For 70, 81 and 90 k Vp all centers were within the limit. 73% of centers were within the level of HVL test, but 27% of them were out of the limit 80% of centers had a linear relationship between m As and dose, but three centers had no linear relationship. For time reproducibility 80% of centers were within the time reproducibility and 13% were out of limit. The beam on control and indicator were available and functional for all centers. The warning light was present in one center. But 93% of centers, but 20% of centers had no window lead glass. Lead aprons were available and functional in all centers. The gloves were available and functional in 33% of centers. But in 67% of centers they were not present. Gonads shields were present in 33% of centers, but not available for 67% of centers.(Author)

  19. High-resolution X-ray television and high-resolution video recorders

    International Nuclear Information System (INIS)

    Haendle, J.; Horbaschek, H.; Alexandrescu, M.

    1977-01-01

    The improved transmission properties of the high-resolution X-ray television chain described here make it possible to transmit more information per television image. The resolution in the fluoroscopic image, which is visually determined, depends on the dose rate and the inertia of the television pick-up tube. This connection is discussed. In the last few years, video recorders have been increasingly used in X-ray diagnostics. The video recorder is a further quality-limiting element in X-ray television. The development of function patterns of high-resolution magnetic video recorders shows that this quality drop may be largely overcome. The influence of electrical band width and number of lines on the resolution in the X-ray television image stored is explained in more detail. (orig.) [de

  20. Quality and Impact of Indian Doppler Weather Radar Wind Profiles: A Diagnostic Study

    Science.gov (United States)

    Sandeep, A.; Prasad, V. S.; Johny, C. J.

    2017-07-01

    In the tropics, efficient weather forecasts require high-quality vertical profiles of winds to overcome improper coupling of mass and wind fields and balance relationships in the region. The India Meteorological Department (IMD) operates the network of Doppler Weather Radar (DWR) in microwave frequencies (S-band or C-band) at various locations in India. The National Centre for Medium Range Weather Forecasting (NCMRWF) receives the volume velocity processing (VVP) wind profiles from all DWRs through the Global Telecommunication System (GTS) network in near real time. The radar VVP wind is a mean horizontal wind derived at different heights from radial velocities suitable for numerical weather prediction applications. Three numerical experiments, CNTL (without VVP winds), 3DVAR and HYBRID with the assimilation of VVP winds by means of 3-dimensional variational (3dvar) and hybrid data assimilation systems were conducted using the NCMRWF Global Forecast System (NGFS) model. This study had two objectives: (1) quality assessment of VVP winds and (2) investigation of the impact of VVP wind profiles on NGFS model forecast. The quality of VVP wind profiles was assessed against the NGFS model background and radiosonde wind profiles. The absolute values of zonal and meridional wind observation minus background (O-B) increased with the pressure for all DWRs. All radars exhibited the accepted (rejected) ratio as a decreasing (increasing) function of pressure. The resemblance between the zonal and meridional O-B statistics for 3DVAR and HYBRID experiments is apparently remarkable. The accepted VVP winds and radiosonde winds in both experiments (3DVAR and HYBRID) were consistent. The correlation coefficient ( R) was higher at Patna (Patiala) for zonal (meridional) winds in the 3DVAR experiment and at Patna (Jaipur) in the HYBRID experiment. At Chennai, the R value was lower in both the experiments for both wind components. However, because of the assimilation of VVP winds by

  1. Video Golf

    Science.gov (United States)

    1995-01-01

    George Nauck of ENCORE!!! invented and markets the Advanced Range Performance (ARPM) Video Golf System for measuring the result of a golf swing. After Nauck requested their assistance, Marshall Space Flight Center scientists suggested video and image processing/computing technology, and provided leads on commercial companies that dealt with the pertinent technologies. Nauck contracted with Applied Research Inc. to develop a prototype. The system employs an elevated camera, which sits behind the tee and follows the flight of the ball down range, catching the point of impact and subsequent roll. Instant replay of the video on a PC monitor at the tee allows measurement of the carry and roll. The unit measures distance and deviation from the target line, as well as distance from the target when one is selected. The information serves as an immediate basis for making adjustments or as a record of skill level progress for golfers.

  2. Quality and safety of integrated community case management of malaria using rapid diagnostic tests and pneumonia by community health workers.

    Science.gov (United States)

    Hamer, Davidson H; Brooks, Erin Twohig; Semrau, Katherine; Pilingana, Portipher; MacLeod, William B; Siazeele, Kazungu; Sabin, Lora L; Thea, Donald M; Yeboah-Antwi, Kojo

    2012-03-01

    To assess the quality and safety of having community health workers (CHWs) in rural Zambia use rapid diagnostic tests (RDTs) and provide integrated management of malaria and pneumonia. In the context of a cluster-randomized controlled trial of two models for community-based management of malaria and/or non-severe pneumonia in children under 5 years old, CHWs in the intervention arm were trained to use RDTs, follow a simple algorithm for classification and treat malaria with artemether-lumefantrine (AL) and pneumonia with amoxicillin. CHW records were reviewed to assess the ability of the CHWs to appropriately classify and treat malaria and pneumonia, and account for supplies. Patients were also followed up to assess treatment safety. During the 12-month study, the CHWs evaluated 1017 children with fever and/or fast/difficult breathing and performed 975 RDTs. Malaria and/or pneumonia were appropriately classified 94-100% of the time. Treatment based on disease classification was correct in 94-100% of episodes. Supply management was excellent with over 98% of RDTs, amoxicillin, and AL properly accounted for. The use of RDTs, amoxicillin, and AL was associated with few minor adverse events. Most febrile children (90%) with negative RDT results recovered after being treated with an antipyretic alone. Volunteer CHWs in rural Zambia are capable of providing integrated management of malaria and pneumonia to children safely and at high quality.

  3. SveDem, the Swedish Dementia Registry - a tool for improving the quality of diagnostics, treatment and care of dementia patients in clinical practice.

    Directory of Open Access Journals (Sweden)

    Dorota Religa

    Full Text Available The Swedish Dementia Registry (SveDem was developed with the aim to improve the quality of diagnostic work-up, treatment and care of patients with dementia disorders in Sweden.SveDem is an internet based quality registry where several indicators can be followed over time. It includes information about the diagnostic work-up, medical treatment and community support (www.svedem.se. The patients are diagnosed and followed-up yearly in specialist units, primary care centres or in nursing homes.The database was initiated in May 2007 and covers almost all of Sweden. There were 28 722 patients registered with a mean age of 79.3 years during 2007-2012. Each participating unit obtains continuous online statistics from its own registrations and they can be compared with regional and national data. A report from SveDem is published yearly to inform medical and care professionals as well as political and administrative decision-makers about the current quality of diagnostics, treatment and care of patients with dementia disorders in Sweden.SveDem provides knowledge about current dementia care in Sweden and serves as a framework for ensuring the quality of diagnostics, treatment and care across the country. It also reflects changes in quality dementia care over time. Data from SveDem can be used to further develop the national guidelines for dementia and to generate new research hypotheses.

  4. Video Analytics

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Distante, Cosimo; Hua, Gang

    2017-01-01

    This book collects the papers presented at two workshops during the 23rd International Conference on Pattern Recognition (ICPR): the Third Workshop on Video Analytics for Audience Measurement (VAAM) and the Second International Workshop on Face and Facial Expression Recognition (FFER) from Real...... World Videos. The workshops were run on December 4, 2016, in Cancun in Mexico. The two workshops together received 13 papers. Each paper was then reviewed by at least two expert reviewers in the field. In all, 11 papers were accepted to be presented at the workshops. The topics covered in the papers...

  5. Video Analytics

    DEFF Research Database (Denmark)

    This book collects the papers presented at two workshops during the 23rd International Conference on Pattern Recognition (ICPR): the Third Workshop on Video Analytics for Audience Measurement (VAAM) and the Second International Workshop on Face and Facial Expression Recognition (FFER) from Real...... World Videos. The workshops were run on December 4, 2016, in Cancun in Mexico. The two workshops together received 13 papers. Each paper was then reviewed by at least two expert reviewers in the field. In all, 11 papers were accepted to be presented at the workshops. The topics covered in the papers...

  6. [Quality assessment of microscopic examination in tuberculosis diagnostic laboratories: a preliminary study].

    Science.gov (United States)

    Simşek, Hülya; Ceyhan, Ismail; Tarhan, Gülnur; Güner, Uğur

    2010-10-01

    Recently, the diagnosis of pulmonary tuberculosis (TB) has based on smear microscopy in the Direct Observed Treatment Strategy (DOTS) programme which provides the basis of treatment worldwide. Microscopic detection of AFB (Acid-Fast Bacilli) is one of the main components in the National TB Control Programmes (NTCP). Precision level in microscopy procedures and evaluations are the most important steps for accurate diagnosis of the disease and to initiate proper treatment. Therefore, the external quality assessment (EQA) is the most important implement to provide the reliability and validity of tests. In countries where NTCP are performed, this task is fulfilled by the National Reference Laboratories (NRL) according to the guidelines of the World Health Organization (WHO). For this purpose a pilot study was initiated by the central NRL of Turkey for EQA of AFB smear microscopy as part of the NTCP on January 1, 2005. A total of 5 laboratories of which 2 were district TB laboratories (A, B), 2 were tuberculosis control dispensaries (C, D), 1 was a national reference laboratory (E), participated in this study. Blind re-checking method (re-examination of randomly selected slides) was used for the evaluation, and the slides were sent to the central NRL with 3 months interval, four times a year, selected according to LQAS (Lot Quality Assurance Sampling) guides. In the re-evaluation of the slides, false positivity (FP), false negativity (FN) and quantification errors (QE) were noted. Laboratory A, sent totally 525 slides between January 1, 2005 and April 1, 2008. In the result of re-checking, 514 (97.9%) slides were found concordant, and 11 (2.1%) were discordant (10 FP, 1 FN). Laboratory B, participated in the study between October 1, 2005 and July 1, 2006 and of the 67 re-examined slides, 60 (89.5%) were concordant and 7 (10.5%) were discordant (2 FP, 0 FN, 5 QE). Laboratory C, sent 235 slides between January 1, 2005 and April 1, 2006; of them 218 (92.8%) were detected

  7. Free magnetic energy and relative magnetic helicity diagnostics for the quality of NLFF field extrapolations

    Science.gov (United States)

    Moraitis, Kostas; Archontis, Vasilis; Tziotziou, Konstantinos; Georgoulis, Manolis K.

    We calculate the instantaneous free magnetic energy and relative magnetic helicity of solar active regions using two independent approaches: a) a non-linear force-free (NLFF) method that requires only a single photospheric vector magnetogram, and b) well known semi-analytical formulas that require the full three-dimensional (3D) magnetic field structure. The 3D field is obtained either from MHD simulations, or from observed magnetograms via respective NLFF field extrapolations. We find qualitative agreement between the two methods and, quantitatively, a discrepancy not exceeding a factor of 4. The comparison of the two methods reveals, as a byproduct, two independent tests for the quality of a given force-free field extrapolation. We find that not all extrapolations manage to achieve the force-free condition in a valid, divergence-free, magnetic configuration. This research has been co-financed by the European Union (European Social Fund - ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: Thales. Investing in knowledge society through the European Social Fund.

  8. [Video documentation in forensic practice].

    Science.gov (United States)

    Schyma, C; Schyma, P

    1995-01-01

    The authors report in part 1 about their experiences with the Canon Ex1 Hi camcorder and the possibilities of documentation with the modern video technique. Application examples in legal medicine and criminalistics are described autopsy, scene, reconstruction of crimes etc. The online video documentation of microscopic sessions makes the discussion of findings easier. The use of video films for instruction produces a good resonance. The use of the video documentation can be extended by digitizing (Part 2). Two frame grabbers are presented, with which we obtained good results in digitizing of images captured from video. The best quality of images is achieved by online use of an image analysis chain. Corel 5.0 and PicEd Cora 4.0 allow complete image processings and analysis. The digital image processing influences the objectivity of the documentation. The applicabilities of image libraries are discussed.

  9. Watermarking textures in video games

    Science.gov (United States)

    Liu, Huajian; Berchtold, Waldemar; Schäfer, Marcel; Lieb, Patrick; Steinebach, Martin

    2014-02-01

    Digital watermarking is a promising solution to video game piracy. In this paper, based on the analysis of special challenges and requirements in terms of watermarking textures in video games, a novel watermarking scheme for DDS textures in video games is proposed. To meet the performance requirements in video game applications, the proposed algorithm embeds the watermark message directly in the compressed stream in DDS files and can be straightforwardly applied in watermark container technique for real-time embedding. Furthermore, the embedding approach achieves high watermark payload to handle collusion secure fingerprinting codes with extreme length. Hence, the scheme is resistant to collusion attacks, which is indispensable in video game applications. The proposed scheme is evaluated in aspects of transparency, robustness, security and performance. Especially, in addition to classical objective evaluation, the visual quality and playing experience of watermarked games is assessed subjectively in game playing.

  10. Video Classification and Adaptive QoP/QoS Control for Multiresolution Video Applications on IPTV

    Directory of Open Access Journals (Sweden)

    Huang Shyh-Fang

    2012-01-01

    Full Text Available With the development of heterogeneous networks and video coding standards, multiresolution video applications over networks become important. It is critical to ensure the service quality of the network for time-sensitive video services. Worldwide Interoperability for Microwave Access (WIMAX is a good candidate for delivering video signals because through WIMAX the delivery quality based on the quality-of-service (QoS setting can be guaranteed. The selection of suitable QoS parameters is, however, not trivial for service users. Instead, what a video service user really concerns with is the video quality of presentation (QoP which includes the video resolution, the fidelity, and the frame rate. In this paper, we present a quality control mechanism in multiresolution video coding structures over WIMAX networks and also investigate the relationship between QoP and QoS in end-to-end connections. Consequently, the video presentation quality can be simply mapped to the network requirements by a mapping table, and then the end-to-end QoS is achieved. We performed experiments with multiresolution MPEG coding over WIMAX networks. In addition to the QoP parameters, the video characteristics, such as, the picture activity and the video mobility, also affect the QoS significantly.

  11. The role of external quality assessment in the verification of in vitro medical diagnostics in the traceability era.

    Science.gov (United States)

    Braga, Federica; Pasqualetti, Sara; Panteghini, Mauro

    2018-02-09

    Once an in-vitro diagnostic (IVD) measuring system has been marketed and introduced into daily practice, the possible sources of degradation of its performance are numerous. It is therefore essential to put in place a continuous post-market surveillance of the quality of performance of the IVD system and of the laboratories that perform measurements in clinical setting. The participation to external quality assessment (EQA) schemes that meet specific metrological criteria is central to the evaluation of performance of clinical laboratories in terms of standardization and clinical suitability of their measurements. In addition to the use of commutable materials, in this type of EQA it is necessary to assign values (and uncertainty) to them with reference procedures and to define and apply clinically permissible analytical performance specifications to substantiate the suitability of laboratory measurements in the clinical setting. Unfortunately, there are still few permanent EQA programs fully covering these requirements because some practical constraints, including technical and economic aspects, which limit their introduction. It is, however, clear that these issues should be quickly overcome, since EQA schemes are in a unique position to add substantial value to the practice of laboratory medicine, by identifying analytes that need improved harmonization and by stimulating and sustaining standardization initiatives that are needed to support clinical practice. Importantly, this will definitively help those manufacturers that produce superior products to demonstrate the superiority of those products and oblige end users (and consequently industry) to abandon assays with demonstrated insufficient quality. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  12. Impact of Periodontal Disease on the Quality of Life of Diabetics Based on Different Clinical Diagnostic Criteria

    Directory of Open Access Journals (Sweden)

    Aline Mendes Silva de Pinho

    2012-01-01

    Full Text Available The aim of this study was to determine the impact of periodontal disease on the quality of life of individuals with diabetes according to different clinical criteria (I-AAP, II-Beck, III-Machtei, IV-Lopez, V-Albandar, VI-Tonetti, and VII-CPI. This cross-sectional study sampled 300 individuals in Belo Horizonte, Brazil. The Oral Health Impact Profile was used to measure the impact of periodontal disease on quality of life. Prevalence of periodontal disease was 35.3%, 30.7%, 35.0%, 9.7%, 92.3%, 25.3%, and 75.3% using criteria I, II, III, IV, V, VI, and VII, respectively. The III-Machtei (P=0.043 and IV-Lopez (P<0.001 criteria were associated with OHIP-14; functional limitation was associated with IV-Lopez (P=0.006 and V-Albandar (P=0.018 criteria. Pain was only associated with V-Albandar criteria (P<0.001. Psychological discomfort was associated with the IV-Lopez (P=0.018 criteria. Physical disability was associated with the IV-Lopez (P=0.047 and V-Tonetti (P=0.046 criteria. Being handicapped was associated with the I-AAP (P=0.025 and II-Beck (P=0.041 criteria. Concepts of health and disease determined by clinical diagnostic criteria may influence the assessment of the impact of periodontal disease on diabetics' quality of life.

  13. Effects of music videos on sleep quality in middle-aged and older adults with chronic insomnia: a randomized controlled trial.

    Science.gov (United States)

    Lai, Hui-Ling; Chang, En-Ting; Li, Yin-Ming; Huang, Chiung-Yu; Lee, Li-Hua; Wang, Hsiu-Mei

    2015-05-01

    Listening to soothing music has been used as a complementary therapy to improve sleep quality. However, there is no empirical evidence for the effects of music videos (MVs) on sleep quality in adults with insomnia as assessed by polysomnography (PSG). In this randomized crossover controlled trial, we compared the effects of a peaceful Buddhist MV intervention to a usual-care control condition before bedtime on subjective and objective sleep quality in middle-aged and older adults with chronic insomnia. The study was conducted in a hospital's sleep laboratory. We randomly assigned 38 subjects, aged 50-75 years, to an MV/usual-care sequence or a usual-care/MV sequence. After pretest data collection, testing was held on two consecutive nights, with subjects participating in one condition each night according to their assigned sequence. Each intervention lasted 30 min. Sleep was assessed using PSG and self-report questionnaires. After controlling for baseline data, sleep-onset latency was significantly shorter by approximately 2 min in the MV condition than in the usual-care condition (p = .002). The MV intervention had no significant effects relative to the usual care on any other sleep parameters assessed by PSG or self-reported sleep quality. These results suggest that an MV intervention may be effective in promoting sleep. However, the effectiveness of a Buddhist MV on sleep needs further study to develop a culturally specific insomnia intervention. Our findings also suggest that an MV intervention can serve as another option for health care providers to improve sleep onset in people with insomnia. © The Author(s) 2014.

  14. Part Two: Learning Science Through Digital Video: Student Views on Watching and Creating Videos

    Science.gov (United States)

    Wade, P.; Courtney, A. R.

    2014-12-01

    The use of digital video for science education has become common with the wide availability of video imagery. This study continues research into aspects of using digital video as a primary teaching tool to enhance student learning in undergraduate science courses. Two survey instruments were administered to undergraduate non-science majors. Survey One focused on: a) What science is being learned from watching science videos such as a "YouTube" clip of a volcanic eruption or an informational video on geologic time and b) What are student preferences with regard to their learning (e.g. using video versus traditional modes of delivery)? Survey Two addressed students' perspectives on the storytelling aspect of the video with respect to: a) sustaining interest, b) providing science information, c) style of video and d) quality of the video. Undergraduate non-science majors were the primary focus group in this study. Students were asked to view video segments and respond to a survey focused on what they learned from the segments. The storytelling aspect of each video was also addressed by students. Students watched 15-20 shorter (3-15 minute science videos) created within the last four years. Initial results of this research support that shorter video segments were preferred and the storytelling quality of each video related to student learning.

  15. Spatial resolution measurements by Radia diagnostic software with SEDENTEXCT image quality phantom in cone beam CT for dental use.

    Science.gov (United States)

    Watanabe, Hiroshi; Nomura, Yoshikazu; Kuribayashi, Ami; Kurabayashi, Tohru

    2018-02-01

    We aimed to employ the Radia diagnostic software with the safety and efficacy of a new emerging dental X-ray modality (SEDENTEXCT) image quality (IQ) phantom in CT, and to evaluate its validity. The SEDENTEXCT IQ phantom and Radia diagnostic software were employed. The phantom was scanned using one medical full-body CT and two dentomaxillofacial cone beam CTs. The obtained images were imported to the Radia software, and the spatial resolution outputs were evaluated. The oversampling method was employed using our original wire phantom as a reference. The resultant modulation transfer function (MTF) curves were compared. The null hypothesis was that MTF curves generated using both methods would be in agreement. One-way analysis of variance tests were applied to the f50 and f10 values from the MTF curves. The f10 values were subjectively confirmed by observing the line pair modules. The Radia software reported the MTF curves on the xy-plane of the CT scans, but could not return f50 and f10 values on the z-axis. The null hypothesis concerning the reported MTF curves on the xy-plane was rejected. There were significant differences between the results of the Radia software and our reference method, except for f10 values in CS9300. These findings were consistent with our line pair observations. We evaluated the validity of the Radia software with the SEDENTEXCT IQ phantom. The data provided were semi-automatic, albeit with problems and statistically different from our reference. We hope the manufacturer will overcome these limitations.

  16. Online NIR diagnostic of laser welding processes and its potential for quality assuring sensor systems

    Science.gov (United States)

    Dorsch, Friedhelm; Braun, Holger; Keβler, Steffen; Pfitzner, Dieter; Rominger, Volker

    2014-02-01

    We have integrated an imaging thermographic sensor into commercial welding optics for observation of the weld zone. Key element of the sensor is an InGaAs-camera that detects the thermal radiation of the welding process in the wavelength range of 1,200 to 1,700 nm. This is well suited to record images of the keyhole, the melt pool and the thermal trace. The sensor was integrated to the welding heads for on-axis observation to minimize the interfering contour to ensure easy adaption to industrial processes. The welding heads used were established industrial-grade TRUMPF optics: a BEO fixed optics with 280 mm focal length, or a TRUMPF PFO-3D scanner optics with 450 mm focal length. We used a TRUMPF TruDisk 16002 16kW-thin disk laser that transmits its power through a 200 μm core diameter light cable. The images were recorded and features of the various process zones were evaluated by image processing. It turns out that almost all weld faults can be clearly detected in the NIR images. Quantitative features like the dimension of the melt pool and the thermal trace can be derived from the captured images. They are correlated to process input parameters as well as to process results. In contrast to observation in the visible spectrum the NIR camera records the melt pool without auxiliary illumination. As an unrivaled attribute of the NIR sensor it supports an online heat flow thermography of the seam and allows identifying missing fusion ("false friends") of lap joints virtually during the welding process. Automated weld fault detection and documentation is possible by online image processing which sets the basis for comprehensive data documentation for quality assurance and traceability.

  17. External Quality Assessment of MERS-CoV Molecular Diagnostics During the 2015 Korean Outbreak.

    Science.gov (United States)

    Seong, Moon Woo; Lee, Seung Jun; Cho, Sung Im; Ko, Kyungphil; Kim, Mi Na; Sung, Heungsub; Kim, Jae Seok; Ahn, Ji Soo; Yu, Byung Su; Kim, Taek Soo; Kim, Eui Chong; Park, Sung Sup

    2016-05-01

    The largest outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infection outside Middle East Asia in 2015 has necessitated the rapid expansion of laboratories that conduct MERS-CoV molecular testing in Korea, together with external quality assessment (EQA) to evaluate the assays used. The EQA program consisted of two phases; self-validation and blind assessment. For the first EQA phase, in vitro transcribed upstream region of the envelope gene (upE) and the open reading frame (ORF)1a RNAs were used at a concentration of 1,000 copies/μL. The test panel for the second EQA phase consisted of RNA extracts from three samples, which were obtained from two MERS-CoV positive patients and one MERS-CoV negative patient. The first EQA phase results for 46 participants showed a linear relationship between the threshold cycle (C(T)) values of RNA materials and the logarithmic concentrations for both upE and ORF1a gene targets (R²=0.73 and 0.75, respectively). The mean C(T) value for each concentration was different depending on which commercial kit was used for the assay. Among the three commonly used kits, PowerChek MERS Real-Time PCR kit (KogeneBiotech, Korea) showed the lowest C(T) values at all concentrations of upE and most concentrations of ORF1a. The second EQA phase results for 47 participants were 100% correct for all tested samples. This EQA survey demonstrates that the MERS-CoV molecular testing performed in Korea during the 2015 outbreak is of robust capability. However, careful establishment and validation of a cut-off value are recommended to ensure good analytical sensitivity.

  18. Akademisk video

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2017-01-01

    der dog opstået nye muligheder og udfordringer i forhold til at formidle og distribuere forskningsresultater til forskellige målgrupper via video. Samtidig er klassiske metodologiske problematikker som forskerens positionering i forhold til det undersøgte stadig aktuelle. Både klassiske og nye...

  19. Status, quality and specific needs of Zika virus (ZIKV) diagnostic capacity and capability in National Reference Laboratories for arboviruses in 30 EU/EEA countries, May 2016.

    Science.gov (United States)

    Mögling, Ramona; Zeller, Hervé; Revez, Joana; Koopmans, Marion; Reusken, Chantal

    2017-09-07

    With international travel, Zika virus (ZIKV) is introduced to Europe regularly. A country's ability to robustly detect ZIKV introduction and local transmission is important to minimise the risk for a ZIKV outbreak. Therefore, sufficient expertise and diagnostic capacity and capability are required in European laboratories. To assess the capacity, quality, operational specifics (guidelines and algorithms), technical and interpretation issues and other possible difficulties that were related to ZIKV diagnostics in European countries, a questionnaire was conducted among national reference laboratories in 30 countries in the European Union/European Economic Area (EU/EEA) in May 2016. While the coverage and capacity of ZIKV diagnostics in the EU/EEA national reference laboratories were found to be adequate, the assessment of the quality and needs indicated several crucial points of improvement that will need support at national and EU/EEA level to improve ZIKV preparedness, response and EU/EEA ZIKV surveillance activities. This article is copyright of The Authors, 2017.

  20. MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  1. MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

    International Nuclear Information System (INIS)

    2015-01-01

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  2. Intelligent network video understanding modern video surveillance systems

    CERN Document Server

    Nilsson, Fredrik

    2008-01-01

    Offering ready access to the security industry's cutting-edge digital future, Intelligent Network Video provides the first complete reference for all those involved with developing, implementing, and maintaining the latest surveillance systems. Pioneering expert Fredrik Nilsson explains how IP-based video surveillance systems provide better image quality, and a more scalable and flexible system at lower cost. A complete and practical reference for all those in the field, this volume:Describes all components relevant to modern IP video surveillance systemsProvides in-depth information about ima

  3. Learning to Swim Using Video Modelling and Video Feedback within a Self-Management Program

    Science.gov (United States)

    Lao, So-An; Furlonger, Brett E.; Moore, Dennis W.; Busacca, Margherita

    2016-01-01

    Although many adults who cannot swim are primarily interested in learning by direct coaching there are options that have a focus on self-directed learning. As an alternative a self-management program combined with video modelling, video feedback and high quality and affordable video technology was used to assess its effectiveness to assisting an…

  4. Performance Analysis of Video Transmission Using Sequential Distortion Minimization Method for Digital Video Broadcasting Terrestrial

    Directory of Open Access Journals (Sweden)

    Novita Astin

    2016-12-01

    Full Text Available This paper presents about the transmission of Digital Video Broadcasting system with streaming video resolution 640x480 on different IQ rate and modulation. In the video transmission, distortion often occurs, so the received video has bad quality. Key frames selection algorithm is flexibel on a change of video, but on these methods, the temporal information of a video sequence is omitted. To minimize distortion between the original video and received video, we aimed at adding methodology using sequential distortion minimization algorithm. Its aim was to create a new video, better than original video without significant loss of content between the original video and received video, fixed sequentially. The reliability of video transmission was observed based on a constellation diagram, with the best result on IQ rate 2 Mhz and modulation 8 QAM. The best video transmission was also investigated using SEDIM (Sequential Distortion Minimization Method and without SEDIM. The experimental result showed that the PSNR (Peak Signal to Noise Ratio average of video transmission using SEDIM was an increase from 19,855 dB to 48,386 dB and SSIM (Structural Similarity average increase 10,49%. The experimental results and comparison of proposed method obtained a good performance. USRP board was used as RF front-end on 2,2 GHz.

  5. The experiences of health-related quality of life in patients with nonspecific symptoms who undergo a diagnostic evaluation for cancer

    DEFF Research Database (Denmark)

    Moseholm, Ellen; Lindhardt, Bjarne Oerskov; Rydahl-Hansen, Susan

    2017-01-01

    of Cancer Quality of Life questionnaire (EORCT-QLQ-C30). Data analysis was based on qualitative content analysis by Krippendorff. The analysis generated six categories: symptoms, physical-, role-, emotional-, cognitive- and social functioning, and the diagnostic fast-track experience. From these categories...

  6. Digital versus traditional: are diagnostic accuracy rates similar for glass slides versus whole slide images in a non-gynaecological external quality assurance setting?

    Science.gov (United States)

    Ross, Jennifer; Greaves, Janelle; Earls, Peter; Shulruf, Boaz; Van Es, Simone L

    2018-04-17

    The Royal College of Pathologists of Australasia Quality Assurance Programs introduced virtual microscopy cases into its cytopathology non-gynaecological program after a short pilot phase, to address the challenges of providing a purely glass slide-based external quality assurance program to multiple participants both locally and internationally. The use of whole slide image (WSI) cases has facilitated a more robust program in relation to standardised material and statistical analysis, with access to a wider variety of specimen types and diagnostic entities. Diagnostic accuracy rates on 56 WSI were assessed against the reference diagnosis. A portion (12) of these WSI slides had been used in glass slide format in previous EQA surveys, and the results of these were compared to the responses received as glass slide cases. Overall diagnostic accuracy for the 56 WSI cases was acceptable in comparison to the reference diagnosis. When these 12 cases were analysed individually, for seven of the twelve cases, virtual format was found to be not inferior to glass slides for diagnostic accuracy. For one case, accuracy using WSI for diagnosis was superior to glass format. Diagnostic accuracy, using WSI for cases in our external quality assurance program is acceptable. As the use of digital microscopy in a large scale external quality assurance program (eQAP) offers extensive advantages over a glass slide-based format, our results encourage future comparison of diagnostic accuracy for virtual compared to glass slide format at a point in time where pathologists are becoming increasingly familiar with virtual microscopy in everyday practice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  7. External quality assessment of tumour marker analysis: state of the art and consequences for estimating diagnostic sensitivity and specificity

    Directory of Open Access Journals (Sweden)

    Wood, William Graham

    2005-05-01

    Full Text Available This review shows the current analytical quality for the following analytes used as tumour markers in the external quality assessment (EQA-programmes of Instand e.V., a national EQA-organiser in Germany: Corticotropin (ACTH, growth hormone (GH, hGH, prolactin (PRL, chorionic gonadotropin (CG, hCG, calcitonin (CT, hCT, thyroglobulin (Tg, carcinoembryonic antigen (CEA, CA-Antigens 125, 72-4, 15-3 and 19-9, alpha foetoprotein (AFP and prostate-specific antigen (PSA. The results from the participants show a large variation in the precision of the methods used as well as in the comparability of results between methods for the same analyte. In general, the hormones used as tumour markers show better performance than the "CA-markers", which are often inadequately standardised and defined. In the case of one CA-marker (CA 72-4/TAG 72-4, the differences between the lowest kit median concentration and highest kit median concentration for one sample pair were 440% and 580%. The corresponding figures for ACTH were 123% and 156% and for CEA 180% and 184%. The classical tumour markers such as carcinoembryonic antigen (CEA and alpha foetoprotein (AFP performed markedly better than the CA-markers and PSA with regards to both inter- and intra-method comparability. The inter-laboratory precision for a given kit and marker was acceptable in many cases. The results show that only results from the same kit/method for each tumour marker can be used for cumulative or time-dependent comparison of results - for example pre-operative and post-operative follow up. In the case of prostate specific antigen (PSA, the kits used for free and total PSA must come from the same producer, if the generally accepted ratios are to have any diagnostic value. The need for kit- and laboratory-specific reference ranges and cut-off values for setting diagnostic specificity and sensitivity is highlighted from the EQA-results. The situation for inter-method comparability for the CA

  8. Solid state video cameras

    CERN Document Server

    Cristol, Y

    2013-01-01

    Solid State Video Cameras reviews the state of the art in the field of solid-state television cameras as compiled from patent literature. Organized into 10 chapters, the book begins with the basic array types of solid-state imagers and appropriate read-out circuits and methods. Documents relating to improvement of picture quality, such as spurious signal suppression, uniformity correction, or resolution enhancement, are also cited. The last part considerssolid-state color cameras.

  9. Video compression and wireless narrowband communication

    Science.gov (United States)

    Drum, David T.; Hsu, Charles C.

    1998-03-01

    The challenge of narrow-band video transmission is to produce smooth motion and acceptable image quality. Advances in commercial video teleconferencing have produced products capable of transmitting audio, video, and control information over wired communication channels at increasingly lower bit rates. Wireless narrow-band communication channels require a portion of their bandwidth to be reserved for error resilient coding further reducing the amount of available bandwidth for video. This paper presents the results of wavelet based pre- and post- processing algorithms wrapped around an industry standard video coder/decoder. This WaveNet Wrapper provides an increase in frame rate and codec efficiency for a given bit rate.

  10. Improvement of diagnostic agreement among pathologists in resolving an "atypical glands suspicious for cancer" diagnosis in prostate biopsies using a novel "Disease-Focused Diagnostic Review" quality improvement process.

    Science.gov (United States)

    Shah, Rajal B; Leandro, Gioacchino; Romerocaces, Gloria; Bentley, James; Yoon, Jiyoon; Mendrinos, Savvas; Tadros, Yousef; Tian, Wei; Lash, Richard

    2016-10-01

    One of the major goals of an anatomic pathology laboratory quality program is to minimize unwarranted diagnostic variability and equivocal reporting. This study evaluated the utility of Miraca Life Sciences' "Disease-Focused Diagnostic Review" (DFDR) quality program in improving interobserver diagnostic reproducibility associated with classification of "atypical glands suspicious for adenocarcinoma" (ATYP) in prostate biopsies. Seventy-one selected prostate biopsies with a focus of ATYP were reviewed by 8 pathologists. Participants were blinded to the original diagnosis and were first asked to classify the ATYP as benign, atypical, or limited adenocarcinoma. DFDR comprised a "theoretical consensus" (in which pathologists first reached consensus on the morphological features they considered relevant for the diagnosis of limited prostatic adenocarcinoma), a didactic review including relevant literature, and "practical consensus" (pathologists performed joint microscopic sessions, reconciling each other's observations and positions evaluating a separate unique slide set). Participants were finally asked to reclassify the original 71 ATYP cases based on knowledge gleaned from DFDR. Pre- and post-DFDR interobserver reproducibility of overall diagnostic agreement was assessed. Interobserver reproducibility measured by Fleiss κ values of pre- and post-DFDR was 0.36 and 0.59, respectively (P=.006). Post-DFDR, there were significant improvement for "100% concordance" (P=.011) and reduction for "no consensus" (P=.0004) categories. Despite a lower pre-DFDR reproducibility for non-uropathology fellowship-trained (n=3, κ=0.38) versus uropathology fellowship-trained (n=5, κ=0.43) pathologists, both groups achieved similarly high post-DFDR κ levels (κ=0.58 and 0.56, respectively). DFDR represents an effective tool to formally achieve diagnostic consensus and reduce variability associated with critical diagnoses in an anatomic pathology practice. Copyright © 2016 Elsevier

  11. Diagnostic development

    International Nuclear Information System (INIS)

    Barnett, C.F.; Brisson, D.A.; Greco, S.E.

    1978-01-01

    During the past year the far-infrared or submillimeter diagnostic research program resulted in three major developments: (1) an optically pumped 0.385-μm D 2 O-laser oscillator-amplifier system was operated at a power level of 1 MW with a line width of less than 50 MHz; (2) a conical Pyrex submillimeter laser beam dump with a retention efficiency greater than 10 4 was developed for the ion temperature Thompson scattering experiment; and (3) a new diagnostic technique was developed that makes use of the Faraday rotation of a modulated submillimeter laser beam to determine plasma current profile. Measurements of the asymmetric distortion of the H/sub α/ (6563 A) spectral line profile show that the effective toroidal drift velocity, dv/sub two vertical bars i/dT/sub i/, may be used as an indicator of plasma quality and as a complement to other ion temperature diagnostics

  12. A new full-field digital mammography system with and without the use of an advanced post-processing algorithm: Comparison of image quality and diagnostic performance

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hye Shin; Kim, Sun Mi; Jang, Mi Jung; Yun, Bo La; Kim, Boh Young [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Ko, Eun Sook; Han, Boo Kyung [Dept. of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Chang, Jung Min; Yi, Ann; Cho, Nariya; Moon, Woo Kyung [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Choi, Hye Young [Dept. of Radiology, Gyeongsang National University Hospital, Jinju (Korea, Republic of)

    2014-06-15

    To compare new full-field digital mammography (FFDM) with and without use of an advanced post-processing algorithm to improve image quality, lesion detection, diagnostic performance, and priority rank. During a 22-month period, we prospectively enrolled 100 cases of specimen FFDM mammography (Brestige), which was performed alone or in combination with a post-processing algorithm developed by the manufacturer: group A (SMA), specimen mammography without application of {sup M}ammogram enhancement ver. 2.0{sup ;} group B (SMB), specimen mammography with application of {sup M}ammogram enhancement ver. 2.0{sup .} Two sets of specimen mammographies were randomly reviewed by five experienced radiologists. Image quality, lesion detection, diagnostic performance, and priority rank with regard to image preference were evaluated. Three aspects of image quality (overall quality, contrast, and noise) of the SMB were significantly superior to those of SMA (p < 0.05). SMB was significantly superior to SMA for visualizing calcifications (p < 0.05). Diagnostic performance, as evaluated by cancer score, was similar between SMA and SMB. SMB was preferred to SMA by four of the five reviewers. The post-processing algorithm may improve image quality with better image preference in FFDM than without use of the software.

  13. Image quality, radiation dose and diagnostic accuracy of 70 kVp whole brain volumetric CT perfusion imaging: a preliminary study

    International Nuclear Information System (INIS)

    Fang, Xiao Kun; Ni, Qian Qian; Zhou, Chang Sheng; Chen, Guo Zhong; Luo, Song; Zhang, Long Jiang; Lu, Guang Ming; Schoepf, U.J.; Fuller, Stephen R.; De Cecco, Carlo N.

    2016-01-01

    To evaluate image quality and diagnostic accuracy for acute infarct detection and radiation dose of 70 kVp whole brain CT perfusion (CTP) and CT angiography (CTA) reconstructed from CTP source data. Patients were divided into three groups (n = 50 each): group A, 80 kVp, 21 scanning time points; groups B, 70 kVp, 21 scanning time points; group C, 70 kVp, 17 scanning time points. Objective and subjective image quality of CTP and CTA were compared. Diagnostic accuracy for detecting acute infarct and cerebral artery stenosis ≥ 50 % was calculated for CTP and CTA with diffusion weighted imaging and digital subtraction angiography as reference standards. Effective radiation dose was compared. There were no differences in any perfusion parameter value between three groups (P > 0.05). No difference was found in subjective image quality between three groups (P > 0.05). Diagnostic accuracy for detecting acute infarct and vascular stenosis showed no difference between three groups (P > 0.05). Compared with group A, radiation doses of groups B and C were decreased by 28 % and 37 % (both P < 0.001), respectively. Compared with 80 kVp protocol, 70 kVp brain CTP allows comparable vascular and perfusion assessment and lower radiation dose while maintaining high diagnostic accuracy in detecting acute infarct. (orig.)

  14. Image quality, radiation dose and diagnostic accuracy of 70 kVp whole brain volumetric CT perfusion imaging: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Xiao Kun; Ni, Qian Qian; Zhou, Chang Sheng; Chen, Guo Zhong; Luo, Song; Zhang, Long Jiang; Lu, Guang Ming [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Schoepf, U.J. [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Medical University of South Carolina, Ashley River Tower, Division of Cardiovascular Imaging, Charleston, SC (United States); Fuller, Stephen R.; De Cecco, Carlo N. [Medical University of South Carolina, Ashley River Tower, Division of Cardiovascular Imaging, Charleston, SC (United States)

    2016-11-15

    To evaluate image quality and diagnostic accuracy for acute infarct detection and radiation dose of 70 kVp whole brain CT perfusion (CTP) and CT angiography (CTA) reconstructed from CTP source data. Patients were divided into three groups (n = 50 each): group A, 80 kVp, 21 scanning time points; groups B, 70 kVp, 21 scanning time points; group C, 70 kVp, 17 scanning time points. Objective and subjective image quality of CTP and CTA were compared. Diagnostic accuracy for detecting acute infarct and cerebral artery stenosis ≥ 50 % was calculated for CTP and CTA with diffusion weighted imaging and digital subtraction angiography as reference standards. Effective radiation dose was compared. There were no differences in any perfusion parameter value between three groups (P > 0.05). No difference was found in subjective image quality between three groups (P > 0.05). Diagnostic accuracy for detecting acute infarct and vascular stenosis showed no difference between three groups (P > 0.05). Compared with group A, radiation doses of groups B and C were decreased by 28 % and 37 % (both P < 0.001), respectively. Compared with 80 kVp protocol, 70 kVp brain CTP allows comparable vascular and perfusion assessment and lower radiation dose while maintaining high diagnostic accuracy in detecting acute infarct. (orig.)

  15. Feasibility of 320-row area detector CT coronary angiography using 40 mL of contrast material: assessment of image quality and diagnostic accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Rihyeon; Park, Eun-Ah; Lee, Whal; Chung, Jin Wook [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of)

    2016-11-15

    To assess the image quality and diagnostic accuracy of 320-row area detector CT (320-ADCT) coronary angiography using 40 mL of contrast material in comparison with 60-mL protocol. This retrospective study included 183 patients who underwent 320-ADCT coronary angiography using 40 mL of contrast and additional 183 sex- and body mass index-matched patients using 60 mL of contrast constituting the control group. Both groups used the same 5-mL/sec injection rate. Quantitative image quality measurements and diagnostic accuracies were calculated and compared. Mean attenuation and contrast-to-noise ratio (CNR) at the aorta and all coronary arteries were lower in the 40-mL group than in the 60-mL group (all, p < 0.05), except for the CNR at proximal coronary arteries at 100 kVp (p = 0.073). However, the proportion of coronary segments with vessel attenuation >250 HU was not different between groups (all, p > 0.05), except for distal coronary arteries at 80 kVp (p = 0.001). Furthermore, there were no differences in per-patient and per-segment diagnostic accuracies between the groups (all, p > 0.05). 320-ADCT coronary angiography using 40 mL of contrast showed image quality and diagnostic accuracy comparable to the 60-mL protocol, demonstrating the clinical feasibility of lowering the risk of contrast-induced nephropathy through contrast volume reduction. (orig.)

  16. Influence of heart rate on diagnostic accuracy and image quality of 16-slice CT coronary angiography: comparison of multisegment and halfscan reconstruction approaches

    International Nuclear Information System (INIS)

    Dewey, Marc; Teige, Florian; Hamm, Bernd; Laule, Michael

    2007-01-01

    The lower the heart rate the better image quality in multislice computed tomography (MSCT) coronary angiography. We prospectively assessed the influence of heart rate on per-patient diagnostic accuracy and image quality of MSCT coronary angiography and compared adaptive multisegment and standard halfscan reconstruction. A consecutive cohort of 126 patients scheduled to undergo conventional coronary angiography was examined with 16-slice CT. For all heart rate groups, per-patient diagnostic accuracy was significantly higher for multisegment than halfscan reconstruction with values of 95 vs. 79% (p 74 bpm, 41 patients). Differences in diagnostic accuracy between adjacent heart rate groups were only significant for halfscan reconstruction for the comparison between the 65-74 and >74 bpm group (p < 0.05). The vessel lengths free of motion artifacts were significantly longer with multisegment reconstruction in all heart rate groups and for all coronary arteries (p < 0.005). For noninvasive MSCT coronary angiography, both per-patient diagnostic accuracy and image quality decline with increasing heart rate, and multisegment reconstruction at high heart rates yields similar results as standard halfscan reconstruction at low heart rates. (orig.)

  17. Real-time video streaming system for LHD experiment using IP multicast

    International Nuclear Information System (INIS)

    Emoto, Masahiko; Yamamoto, Takashi; Yoshida, Masanobu; Nagayama, Yoshio; Hasegawa, Makoto

    2009-01-01

    In order to accomplish smooth cooperation research, remote participation plays an important role. For this purpose, the authors have been developing various applications for remote participation for the LHD (Large Helical Device) experiments, such as Web interface for visualization of acquired data. The video streaming system is one of them. It is useful to grasp the status of the ongoing experiment remotely, and we provide the video images displayed in the control room to the remote users. However, usual streaming servers cannot send video images without delay. The delay changes depending on how to send the images, but even a little delay might become critical if the researchers use the images to adjust the diagnostic devices. One of the main causes of delay is the procedure of compressing and decompressing the images. Furthermore, commonly used video compression method is lossy; it removes less important information to reduce the size. However, lossy images cannot be used for physical analysis because the original information is lost. Therefore, video images for remote participation should be sent without compression in order to minimize the delay and to supply high quality images durable for physical analysis. However, sending uncompressed video images requires large network bandwidth. For example, sending 5 frames of 16bit color SXGA images a second requires 100Mbps. Furthermore, the video images must be sent to several remote sites simultaneously. It is hard for a server PC to handle such a large data. To cope with this problem, the authors adopted IP multicast to send video images to several remote sites at once. Because IP multicast packets are sent only to the network on which the clients want the data; the load of the server does not depend on the number of clients and the network load is reduced. In this paper, the authors discuss the feasibility of high bandwidth video streaming system using IP multicast. (author)

  18. Is aspiration as detected on pretreatment video fluorography, a harbinger of poor quality of life and early mortality in cancers of the upper aerodigestive tract treated with radiotherapy?

    Directory of Open Access Journals (Sweden)

    Punita Lal

    2014-01-01

    Full Text Available Background: Patients with cancers of the upper aerodigestive tract (head and neck cancer (HNC tend to aspirate, either due to disease or treatment. The association of aspiration (documented on video fluorography (VFG with quality of life (QOL and unexpected mortality was studied prospectively in patients treated with simultaneous integrated boost technique of intensity-modulated radiotherapy (SIB-IMRT. Materials and Methods: Moderately advanced (stage III/IV HNC were treated by SIB-IMRT delivering 66 Gy/30 fr, 60 Gy/30 fr, and 54 Gy/30 fr to high, intermediate, and low risk volumes, respectively. They underwent serial VFG and QOL assessments (Quality of Life Questionnaire-Core 30 ( QLQ-C30 and head and neck-35 (HN35 European Organisation for Research and Treatment of Cancer (EORTC tools at 0, 3, and 6 months. Pharyngeal musculature (PM was additionally delineated on planning computed tomography (CT scans as potential organs at risk (OARs. Results: Between November 2009 and May 2011, 20 HNC were treated as per protocol. All patients were fit (Karnofsky performance status (KPS ≥ 80. Based on VFG findings, seven patients (4/9 oropharynx and 3/11 laryngopharynx were grouped as aspirators (A and remaining 13 as non-aspirators (NA. The QOL study showed that pretreatment coughing and swallowing difficulties were greater in group A versus NA and remained persistently higher. In group A, deaths attributable to aspiration were seen in 3/7 patients, while none occurred in the NA group (Fisher′s exact P = 0.03. The mean PM dose was 60 Gy in both the groups and mean V60 was similar at 69 and 67% in A and NA groups, respectively. Conclusions: VFG helps identify patients who aspirate and are at risk of premature death due to its complications, alerting caregivers to direct attention appropriately.

  19. Classification-based Multi-client Video Transmission over Heterogeneous Networks

    OpenAIRE

    Bo Li; Peng Wang; Yongfei Zhang

    2013-01-01

    These Real-time video streaming over networks operates under stringent network resource constraints, with multiple video clients competing for limited network resources. In this paper, we study the problem of bandwidth allocation for video transmission over heterogeneous networks, with multiple video clients connecting to the video server simultaneously and demanding for the video services, and aim to provide the best possible Quality of Service (QoS) under limited bandwidth of both the video...

  20. The effect of film and paper on quality of Cone beam CT image and their diagnostic accuracy in detection of inferior alveolar canal

    Directory of Open Access Journals (Sweden)

    Ladan Hafezi

    2017-02-01

    Full Text Available Background and Aims: According to the research background and need to print CBCT images in case of emergency, this study has been done to compare the quality and accuracy of the two methods of film and paper printing for CBCT images. Materials and Methods: The study of CBCT images taken from 5 patients was done and the cross-sectional slices on Fotolusio DNP papers and film AGFA were printed. Afterward, the images was exmined by a maxillofacial radiologist. The images’ quality were identified and recorded with anatomical, from 1 to 4 on forms. The accuracy was determined by the diagnosis of alveolar canal area and the comparison with the gold standard. Data were analyzed using independent chi-square and Fisher exact tests’. Results: The images quality in anatomical landmarks consisting PDL (P=0.02, lamina dura (P=0.006, the inferior alveolar canal (P=0.01 and the filling (P=0.006 had a significant difference. There was no significant difference. For the lower border of the mandible landmark, there was no difference between the two methods of printing. In comparing the diagnostic accuracy between the two methods (P=1. Conclusion: The results showed that the diagnostic quality in film printing is better than paper printing and the diagnostic accuracy is the same in both methods.

  1. Quality of Diagnosis and Treatment Plans After Using the 'Diagnostic Guideline for Anxiety and Challenging Behaviours' in People with Intellectual Disabilities: A Comparative Multiple Case Study Design.

    Science.gov (United States)

    Pruijssers, Addy; van Meijel, Berno; Maaskant, Marian; Keeman, Noortje; van Achterberg, Theo

    2016-07-01

    People with intellectual disabilities often have a multitude of concurrent problems due to the combination of cognitive impairments, psychiatric disorders (particularly anxiety) and related challenging behaviours. Diagnoses in people with intellectual disabilities are complicated. This study evaluates the quality of the diagnoses and treatment plans after using a guideline that was developed to support professionals in their diagnostic tasks. A comparative multiple case study with an experimental and control condition, applying deductive analyses of diagnoses and treatment plans. The analyses revealed that the number of diagnostic statements and planned treatment actions in the experimental group was significantly larger and more differentiated than in the control condition. In the control group, consequential harm and protective factors were hardly mentioned in diagnoses and treatment plans. Working with the 'Diagnostic Guideline for Anxiety and CB' leads to improved diagnoses and treatment plans compared with care as usual. © 2015 John Wiley & Sons Ltd.

  2. Prospectively ECG-Triggered Sequential Dual-Source Coronary CT Angiography in Patients with Atrial Fibrillation: Influence of Heart Rate on Image Quality and Evaluation of Diagnostic Accuracy.

    Science.gov (United States)

    Yang, Lin; Xu, Lei; Schoepf, U Joseph; Wichmann, Julian L; Fox, Mary A; Yan, Jing; Fan, Zhanming; Zhang, Zhaoqi

    2015-01-01

    To evaluate the effects of mean heart rate (HR) and heart rate variation (HRV) on image quality and diagnostic accuracy of prospectively ECG-triggered sequential dual-source coronary CT angiography (CCTA) in patients with atrial fibrillation (AF). Eighty-five patients (49 women, 36 men; mean age 62. 1 ± 9.5 years) with persistent AF underwent prospectively ECG-triggered sequential second-generation dual-source CCTA. Tube current and voltage were adjusted according to body mass index (BMI) and iterative reconstruction was used. Image quality of coronary segments (four-point scale) and presence of significant stenosis (>50%) were evaluated. Diagnostic accuracy was analyzed in 30 of the 85 patients who underwent additional invasive coronary angiography (ICA). Only 8 of 1102 (0.7%) segments demonstrated poor image quality. No significant impact on image quality was found for mean HR (94.9 ± 21.8 bpm; r=0.034, p=0.758; F=0.413, p=0.663) or HRV (67.5 ± 22.8 bpm; r=0.097, p=0.377; F=0.111, p=0.895). On per-segment analysis, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 89.7% (26/29), 99.4% (355/357), 92.9% (26/28), and 99.2% (355/358), respectively, with excellent correlation (kappa=0.91) with ICA. Mean effective dose was 3.3 ± 1.0 mSv. Prospectively ECG-triggered sequential dual-source CCTA provides diagnostic image quality and good diagnostic accuracy for detection of coronary stenosis in AF patients without significant influence by HR or HRV.

  3. Smart Video Communication for Social Groups - The Vconect Project

    NARCIS (Netherlands)

    M. Ursu; P. Stollenmayer; D. Williams; P. Torres; P.S. Cesar Garcia (Pablo Santiago); N. Farber; E. Geelhoed

    2014-01-01

    htmlabstractThis article introduces the Vconect project. Vconect (Video Communications for Networked Communities) is a collaborative European research and development project dealing with high-quality enriched video as a medium for mass communication within social communities. The technical

  4. Compliance and quality control monitoring of diagnostic X-ray facilities in Dar es Salaam city, Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Nkuba, Leonid L.; Nyanda, Pendo B., E-mail: leonid.nkuba@taec.or.tz [Tanzania Atomic Energy Commission, Radiation Control Directorate, Dar es Salaam (Tanzania, United Republic of)

    2017-09-01

    The compliance evaluation and quality control measurements on 60 diagnostic X-ray units were performed. The results on legal compliance show that 25 % of X-ray facilities operated without or with an expired license. The rest of the centers were new and had already applied for license and others had valid licenses. For basic requirements compliance, 47 % of X-ray facilities did not have the changing cubicles, 37 % of X-ray facilities did not post radiation warning sign and symbols also 46 % of units were found either without protective gear or operated by unqualified personnel. The QC test results showed that 93 % had X-ray tube voltage within the tolerance limit of 10 % and HVL ≥ 2.3 mmAl, at 80 kV was observed in 98.2 % of the units, whereas 98 % of exposure had acceptable kV reproducibility within the tolerance limit of 5 %. Of the X-ray generators assessed, 93 % had tolerable mAs linearity. 93 % and 97 % had acceptable beam alignment and light beam diaphragm. Of the assessed units, 13 (93 %) had tube leakage < 1000 μGy/hr at 1m. For shielding tests, 47 % of units had radiation levels above 0.5 μSv/hr at the main door leading to the X-ray rooms and the registration area. The dose rates > 10 μSv/hr were recorded at viewing windows, walls and doors of control cubicles and behind the doors of changing cubicles. These dose rates indicating higher health risk to workers and member of public. (author)

  5. Quality assurance in CT: implementation of the updated national diagnostic reference levels using an automated CT dose monitoring system.

    Science.gov (United States)

    Appel, E; Kröpil, P; Bethge, O T; Aissa, J; Thomas, C; Antoch, G; Boos, J

    2018-03-20

    To evaluate the implementation of the updated computed tomography (CT) diagnostic reference levels (DRLs) from the German Federal Office for Radiation Protection into clinical routine using an automatic CT dose monitoring system. CT radiation exposure was analysed before and after implementing the updated national DRLs into routine clinical work in 2016. After the implementation process, institutional CT protocols were mapped to the anatomical regions for which DRLs were provided. Systematically, protocols that exceeded the thresholds were optimised and analysed in detail. The CT radiation output parameters analysed were volumetric CT dose index (CTDIvol) and dose-length product (DLP). Three radiologists evaluated subjective image quality using a three-point Likert scale. The study included 94,258 CT series (from 27,103 CT examinations) in adult patients performed in 2016. When averaged over all body regions with available DRL, institutional CTDIvol/DLP values were always below the DRLs (65.2±32.9%/67.3±41.5% initially; 59.4±32%/60.5±39.9% after optimisation). Values exceeding the national DRLs were found for pelvis (n=268; CTDIvol 107.7±65.7%/DLP 106.3±79.3%), lumbar spine (n=91; 160.8±74.7%/175.2±104.1%), and facial bones (n=527; 108±39%/152.7±75.7%). After optimisation, CTDIvol and DLP were 87.9±73%/87.8±80.8% for the pelvis, 67.8±33.2%/74.5±50.6% for the lumbar spine and 95.1±45.8%/133.3±74.6% for the viscerocranium. An automatic CT dose monitoring system enabled not only comprehensive monitoring of a DRL implementation process but can also help to optimise radiation exposure. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  6. Validation of the Night Eating Diagnostic Questionnaire (NEDQ) and its relationship with depression, sleep quality, "food addiction", and body mass index.

    Science.gov (United States)

    Nolan, Laurence J; Geliebter, Allan

    2017-04-01

    Night eating syndrome (NES) is commonly assessed using the Night Eating Questionnaire (NEQ), a validated scale of symptom severity, which does not assess all diagnostic criteria. The Night Eating Diagnostic Questionnaire (NEDQ) assesses all diagnostic criteria, but has not been fully validated. The study purpose was to establish convergent validity for the NEDQ with the NEQ. It was also expected that higher NEDQ scores would be associated with elevated depression, poorer sleep quality, "food addiction," and BMI as in other studies of NES. Students (n = 254) and community members (n = 468) were administered the NEQ, NEDQ, Pittsburgh Sleep Quality Index, Zung Self-report Depression Scale (SDS), and the Yale Food Addiction Scale (YFAS). Convergent validity between the NEDQ and the NEQ was demonstrated; the scores were significantly positively correlated. There was good agreement between the NEDQ and the NEQ in diagnosis of NES; 56% of those diagnosed by the NEDQ met the threshold score on the NEQ, while the other 44% did not. Only 5 participants out of 33 who met the NEQ threshold score for NES did not meet the NEDQ diagnostic criteria. MANOVA revealed that higher NEDQ was associated with higher SDS and YFAS scores and poorer sleep quality. Full-syndrome NES by the NEDQ was associated with higher BMI in the community group unlike the student group. Scores on all the other questionnaires were higher in the community group. The discrepancies between NEDQ and NEQ diagnosis may be due to differences in construction of the questionnaires and specifically due to the NEDQ being designed for diagnosis. The NEQ provides a convenient global score for NES severity, whereas the NEDQ, which shows convergent validity with the NEQ, provides clinically useful diagnostic categories. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. The Educational Efficacy of Distinct Information Delivery Systems in Modified Video Games

    Science.gov (United States)

    Moshirnia, Andrew; Israel, Maya

    2010-01-01

    Despite the increasing popularity of many commercial video games, this popularity is not shared by educational video games. Modified video games, however, can bridge the gap in quality between commercial and education video games by embedding educational content into popular commercial video games. This study examined how different information…

  8. Next Generation Quality: Assessing the Physician in Clinical History Completeness and Diagnostic Interpretations Using Funnel Plots and Normalized Deviations Plots in 3,854 Prostate Biopsies.

    Science.gov (United States)

    Bonert, Michael; El-Shinnawy, Ihab; Carvalho, Michael; Williams, Phillip; Salama, Samih; Tang, Damu; Kapoor, Anil

    2017-01-01

    Observational data and funnel plots are routinely used outside of pathology to understand trends and improve performance. Extract diagnostic rate (DR) information from free text surgical pathology reports with synoptic elements and assess whether inter-rater variation and clinical history completeness information useful for continuous quality improvement (CQI) can be obtained. All in-house prostate biopsies in a 6-year period at two large teaching hospitals were extracted and then diagnostically categorized using string matching, fuzzy string matching, and hierarchical pruning. DRs were then stratified by the submitting physicians and pathologists. Funnel plots were created to assess for diagnostic bias. 3,854 prostate biopsies were found and all could be diagnostically classified. Two audits involving the review of 700 reports and a comparison of the synoptic elements with the free text interpretations suggest a categorization error rate of 40 cases and together assessed 3,690 biopsies. There was considerable inter-rater variability and a trend toward more World Health Organization/International Society of Urologic Pathology Grade 1 cancers in older pathologists. Normalized deviations plots, constructed using the median DR, and standard error can elucidate associated over- and under-calls for an individual pathologist in relation to their practice group. Clinical history completeness by submitting medical doctor varied significantly (100% to 22%). Free text data analyses have some limitations; however, they could be used for data-driven CQI in anatomical pathology, and could lead to the next generation in quality of care.

  9. Recombinant human G6PD for quality control and quality assurance of novel point-of-care diagnostics for G6PD deficiency.

    Science.gov (United States)

    Kahn, Maria; LaRue, Nicole; Zhu, Changcheng; Pal, Sampa; Mo, Jack S; Barrett, Lynn K; Hewitt, Steve N; Dumais, Mitchell; Hemmington, Sandra; Walker, Adrian; Joynson, Jeff; Leader, Brandon T; Van Voorhis, Wesley C; Domingo, Gonzalo J

    2017-01-01

    A large gap for the support of point-of-care testing is the availability of reagents to support quality control (QC) of diagnostic assays along the supply chain from the manufacturer to the end user. While reagents and systems exist to support QC of laboratory screening tests for glucose-6-phosphate dehydrogenase (G6PD) deficiency, they are not configured appropriately to support point-of-care testing. The feasibility of using lyophilized recombinant human G6PD as a QC reagent in novel point-of-care tests for G6PD deficiency is demonstrated. Human recombinant G6PD (r-G6PD) was expressed in Escherichia coli and purified. Aliquots were stored at -80°C. Prior to lyophilization, aliquots were thawed, and three concentrations of r-G6PD (representing normal, intermediate, and deficient clinical G6PD levels) were prepared and mixed with a protective formulation, which protects the enzyme activity against degradation from denaturation during the lyophilization process. Following lyophilization, individual single-use tubes of lyophilized r-G6PD were placed in individual packs with desiccants and stored at five temperatures for one year. An enzyme assay for G6PD activity was used to ascertain the stability of r-G6PD activity while stored at different temperatures. Lyophilized r-G6PD is stable and can be used as a control indicator. Results presented here show that G6PD activity is stable for at least 365 days when stored at -80°C, 4°C, 30°C, and 45°C. When stored at 55°C, enzyme activity was found to be stable only through day 28. Lyophilized r-G6PD enzyme is stable and can be used as a control for point-of-care tests for G6PD deficiency.

  10. Recombinant human G6PD for quality control and quality assurance of novel point-of-care diagnostics for G6PD deficiency.

    Directory of Open Access Journals (Sweden)

    Maria Kahn

    Full Text Available A large gap for the support of point-of-care testing is the availability of reagents to support quality control (QC of diagnostic assays along the supply chain from the manufacturer to the end user. While reagents and systems exist to support QC of laboratory screening tests for glucose-6-phosphate dehydrogenase (G6PD deficiency, they are not configured appropriately to support point-of-care testing. The feasibility of using lyophilized recombinant human G6PD as a QC reagent in novel point-of-care tests for G6PD deficiency is demonstrated.Human recombinant G6PD (r-G6PD was expressed in Escherichia coli and purified. Aliquots were stored at -80°C. Prior to lyophilization, aliquots were thawed, and three concentrations of r-G6PD (representing normal, intermediate, and deficient clinical G6PD levels were prepared and mixed with a protective formulation, which protects the enzyme activity against degradation from denaturation during the lyophilization process. Following lyophilization, individual single-use tubes of lyophilized r-G6PD were placed in individual packs with desiccants and stored at five temperatures for one year. An enzyme assay for G6PD activity was used to ascertain the stability of r-G6PD activity while stored at different temperatures.Lyophilized r-G6PD is stable and can be used as a control indicator. Results presented here show that G6PD activity is stable for at least 365 days when stored at -80°C, 4°C, 30°C, and 45°C. When stored at 55°C, enzyme activity was found to be stable only through day 28.Lyophilized r-G6PD enzyme is stable and can be used as a control for point-of-care tests for G6PD deficiency.

  11. Evaluation of Two Malaria Rapid Diagnostic Tests Quality Assurance (mRDT’s QA) Methods in Peripheral Health Facilities, Rural Tanzania.

    OpenAIRE

    Masanja, Irene; Maganga, Musa; Sumari, Debora; Lucchi, Naomi; Udhayakumar, Venkatachalam; McMorrow, Meredith; Kachur, Patrick

    2012-01-01

    WHO recommends confirming suspected malaria cases before initiation of treatment. Due to the imited availability of quality microscopy services, this recommendation has been followed with increased use of antigen-detecting malaria rapid diagnostic tests (mRDTs) in many malaria endemic countries. With the increased use of mRDTs, the need for a thorough mRDT quality assurance (RDT QA) method has become more apparent. One of the WHO recommendations for RDT QA is to monitor the tests in field use...

  12. Improved image quality and diagnostic potential using ultra-high-resolution computed tomography of the lung with small scan FOV: A prospective study.

    Science.gov (United States)

    Zhu, Huiyuan; Zhang, Lian; Wang, Yali; Hamal, Preeti; You, Xiaofang; Mao, Haixia; Li, Fei; Sun, Xiwen

    2017-01-01

    The aim of this study was to assess whether CT imaging using an ultra-high-resolution CT (UHRCT) scan with a small scan field of view (FOV) provides higher image quality and helps to reduce the follow-up period compared with a conventional high-resolution CT (CHRCT) scan. We identified patients with at least one pulmonary nodule at our hospital from July 2015 to November 2015. CHRCT and UHRCT scans were conducted in all enrolled patients. Three experienced radiologists evaluated the image quality using a 5-point score and made diagnoses. The paired images were displayed side by side in a random manner and annotations of scan information were removed. The following parameters including image quality, diagnostic confidence of radiologists, follow-up recommendations and diagnostic accuracy were assessed. A total of 52 patients (62 nodules) were included in this study. UHRCT scan provides a better image quality regarding the margin of nodules and solid internal component compared to that of CHRCT (P images than of CHRCT images (Pimages (P 0.05). These findings suggest that the UHRCT prototype scanner provides a better image quality of subsolid nodules compared to CHRCT and contributes significantly to reduce the patients' follow-up period.

  13. Improved image quality and diagnostic potential using ultra-high-resolution computed tomography of the lung with small scan FOV: A prospective study.

    Directory of Open Access Journals (Sweden)

    Huiyuan Zhu

    Full Text Available The aim of this study was to assess whether CT imaging using an ultra-high-resolution CT (UHRCT scan with a small scan field of view (FOV provides higher image quality and helps to reduce the follow-up period compared with a conventional high-resolution CT (CHRCT scan. We identified patients with at least one pulmonary nodule at our hospital from July 2015 to November 2015. CHRCT and UHRCT scans were conducted in all enrolled patients. Three experienced radiologists evaluated the image quality using a 5-point score and made diagnoses. The paired images were displayed side by side in a random manner and annotations of scan information were removed. The following parameters including image quality, diagnostic confidence of radiologists, follow-up recommendations and diagnostic accuracy were assessed. A total of 52 patients (62 nodules were included in this study. UHRCT scan provides a better image quality regarding the margin of nodules and solid internal component compared to that of CHRCT (P 0.05. These findings suggest that the UHRCT prototype scanner provides a better image quality of subsolid nodules compared to CHRCT and contributes significantly to reduce the patients' follow-up period.

  14. Diagnostic concordance of breast pathologists: lessons from the National Health Service Breast Screening Programme Pathology External Quality Assurance Scheme.

    Science.gov (United States)

    Rakha, Emad A; Ahmed, Mohamed A; Aleskandarany, Mohammed A; Hodi, Zsolt; Lee, Andrew H S; Pinder, Sarah E; Ellis, Ian O

    2017-03-01

    Previous concordance studies examining accuracy of breast diagnosis by pathologists, typically targeting difficult, histologically challenging breast lesions using artificial and restrictive environments, have reported aberrantly high levels of diagnostic discordance. The results of these studies may be misinterpreted by non-pathologists and raise concerns relating to routine practice. This study aims to assess the diagnostic agreement among UK breast pathologists. Two hundred and forty consecutive breast lesions, submitted by participants from their routine practice, included in the UK National Health Service Breast Screening Programme (NHSBSP) breast pathology EQA scheme during the last 10 years were reviewed. An average of approximately 600 participants viewed each case. Data on diagnostic categories (benign, atypical, in-situ malignant and invasive malignant) were collected. In this study, benign and atypical diagnoses were grouped together. The overall diagnostic agreement level was in the almost perfect range. Thirty-five cases (14.6%) showed diagnostic concordance of ≤95%. Reasons for discordance included one or more of: (1) scheme methodology limitations such as: (i) miscoding of certain lesions (e.g. phyllodes tumours and lobular neoplasia) (n = 7) and (ii) variable representation of the index lesion on glass slides (n = 18); and (2) diagnostically challenging cases that may be interpreted more easily using immunohistochemistry (n = 28). These latter included benign and malignant papillary lesions (n = 12), complex sclerosing lesions (n = 7), intraductal epithelial proliferative lesions (n = 6) and an unusual special tumour type (n = 1). Further review identified pathologists' misinterpretation in 13 cases (5.4%), with an average discordance rate of only 4.2%. The performance of breast pathologists is high. Exclusion of the effect of the scheme methodology limitations highlights further the high performance rate and identifies true diagnostically

  15. Holografisk Video

    OpenAIRE

    Waldemarsson, Lars-Åke

    2006-01-01

    Detta examensarbete utgår ifrån en artikel i vilken en metod för att skapa holografisk video beskrivs. Syftet med arbetet är att återskapa denna metod. Metoden bygger på projicering av hologram med hjälp av delar från en projektor, en laser och några linser. Först görs en litteraturstudie för att få förståelse över hur metoden fungerar. Här behandlas hur ögat ser djup och vilka olika typer av displayer det finns för att återge tredimensionella holografiska bilder. Vidare beskrivs skillnaden m...

  16. Video Surveillance: All Eyes Turn to IP

    Science.gov (United States)

    Raths, David

    2011-01-01

    Many university officials recognize the need to upgrade their older analog video surveillance systems. In a 2010 survey by "Campus Safety" magazine, half of university respondents expressed dissatisfaction with the quality and coverage of their current video surveillance systems. Among the limitations of analog closed-circuit television…

  17. Processing Decoded Video for Backlight Dimming

    DEFF Research Database (Denmark)

    Burini, Nino; Korhonen, Jari

    Quality of digital image and video signals on TV screens is aected by many factors, including the display technology and compression standards. An accurate knowledge of the characteristics of the display andof the video signals can be used to develop advanced algorithms that improve the visual...

  18. A Directory of English Language Teaching Videos.

    Science.gov (United States)

    Falsetti, Julie, Comp.

    This third edition of the video directory updates previous editions and alphabetically lists videos, by title. It is designed to assist in the teaching of English or the training of teachers of English. Information included are format, standard, variety, use, target, level, price, duration, quality, support materials included, distributor, year…

  19. CT enterography at 80 kVp with adaptive statistical iterative reconstruction versus at 120 kVp with standard reconstruction: image quality, diagnostic adequacy, and dose reduction.

    Science.gov (United States)

    Kaza, Ravi K; Platt, Joel F; Al-Hawary, Mahmoud M; Wasnik, Ashish; Liu, Peter S; Pandya, Amit

    2012-05-01

    The objective of our study was to evaluate the image quality and diagnostic adequacy of the following two CT enterography protocols in patients weighing less than 160 lb (72 kg): 80-kVp imaging with the adaptive statistical iterative reconstruction (ASIR) in comparison with 120-kVp imaging with the filtered back projection reconstruction. We retrospectively reviewed 133 CT enterography examinations of 127 patients weighing less than 160 lb, 64 80-kVp examinations, and 69 120-kVp examinations. Image quality for evaluation of the bowel wall, mesenteric vessels, and hepatic parenchyma and the overall image quality were graded on a scale of 1-5 (1 = poor, 2 = acceptable, 3 = good, 4 = very good, 5 = excellent). Diagnostic accuracy for the detection of inflammatory bowel disease was evaluated. The volume CT dose index (CTDI(vol)) was recorded and effective dose was calculated from scanner-generated dose-length product. There was a statistically significant decrease in the mean image quality scores for 80-kVp examinations compared with 120-kVp examinations for evaluation of the bowel wall (3.19 vs 3.70, respectively) and liver (3.12 vs 3.81) and for overall image quality (3.23 vs 3.68), but there was no significant decrease in score for evaluation of the mesenteric vessels (3.63 vs 3.67). None of the 80-kVp examinations was graded as poor, and all were considered to be of acceptable quality. Both techniques had comparable diagnostic accuracy for the detection of inflammatory bowel disease. Interobserver agreement was fair to moderate for qualitative image grading and was substantial for the detection of features of inflammatory bowel disease. The mean CTDI(vol) and effective dose for the 80-kVp examinations were 6.15 mGy and 4.60 mSv, respectively, and for the 120-kVp examinations, 20.79 mGy and 15.81 mSv. In patients weighing less than 160 lb, CT enterography examinations at 80 kVp with 30% ASIR produce diagnostically acceptable image quality with an average CTDI

  20. Video Tutorial of Continental Food

    Science.gov (United States)

    Nurani, A. S.; Juwaedah, A.; Mahmudatussa'adah, A.

    2018-02-01

    This research is motivated by the belief in the importance of media in a learning process. Media as an intermediary serves to focus on the attention of learners. Selection of appropriate learning media is very influential on the success of the delivery of information itself both in terms of cognitive, affective and skills. Continental food is a course that studies food that comes from Europe and is very complex. To reduce verbalism and provide more real learning, then the tutorial media is needed. Media tutorials that are audio visual can provide a more concrete learning experience. The purpose of this research is to develop tutorial media in the form of video. The method used is the development method with the stages of analyzing the learning objectives, creating a story board, validating the story board, revising the story board and making video tutorial media. The results show that the making of storyboards should be very thorough, and detailed in accordance with the learning objectives to reduce errors in video capture so as to save time, cost and effort. In video capturing, lighting, shooting angles, and soundproofing make an excellent contribution to the quality of tutorial video produced. In shooting should focus more on tools, materials, and processing. Video tutorials should be interactive and two-way.

  1. Health-related quality of life, anxiety and depression in the diagnostic phase of suspected cancer, and the influence of diagnosis.

    Science.gov (United States)

    Moseholm, Ellen; Rydahl-Hansen, Susan; Overgaard, Dorthe; Wengel, Hanne S; Frederiksen, Rikke; Brandt, Malene; Lindhardt, Bjarne Ø

    2016-05-20

    Undergoing diagnostic evaluation for cancer has been associated with a high prevalence of anxiety and depression and affected health-related quality of life (HRQoL). The aims of this study were to assess HRQoL, anxiety, and depression pre- and post-diagnosis in patients undergoing diagnostic evaluations for cancer due to non-specific symptoms; to examine changes over time in relation to final diagnosis (cancer yes/no); and to assess the predictive value of pre-diagnostic psychological, socio-demographic and clinical factors. A prospective, multicenter survey study of patients suspected to have cancer based on non-specific symptoms was performed. Participants completed the EORTC-QLQ-C30 quality of life scale, HADS, SOC-13 and self-rated health before and after completing diagnostic evaluations. Intra- and inter-group differences between patients diagnosed with cancer versus patients with non-cancer diagnoses were calculated. The impact of baseline psychological, socio-demographic, and medical factors on HRQoL, anxiety and depression at follow-up was explored by bootstrapped multivariate linear regression analyses and logistic regression analyses. A total of 838 patients participated in this study; 679 (81 %) completed the follow-up. Twenty-two percent of the patients received a cancer diagnosis at the end of the follow-up. Patients presented initially with a high burden of symptoms and affected role and emotional functioning and global health/QL, irrespective of diagnosis. The prevalence of clinical anxiety prior to knowledge of the diagnosis was 32 % in patients with cancer and 35 % in patients who received a non-cancer diagnosis. HRQoL and anxiety improved after diagnosis, and a larger improvement was seen in patients who received a non-cancer diagnosis. There were no intra- or inter-group differences in the depression scores. The strongest predictors of global QL, anxiety, and depression after a known diagnosis were baseline scores, co-morbidity and poor self

  2. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... YouTube Videos >> NEI YouTube Videos: Amblyopia Listen NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration ... Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: ...

  3. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... YouTube Videos > NEI YouTube Videos: Amblyopia NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia ... of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: Amblyopia ...

  4. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... NEI YouTube Videos > NEI YouTube Videos: Amblyopia NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration ... Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video for NEI YouTube Videos: ...

  5. Comparison of diagnostic quality of kidney biopsy obtained using 16g and 18g needles in patients with diffuse renal disease

    Directory of Open Access Journals (Sweden)

    Komal Arora

    2012-01-01

    Full Text Available To determine the diagnostic quality and complication rates of 16G and 18G needles in biopsy of the kidney, we performed renal biopsy using a biopsy gun under ultrasound guidance in 50 patients who were prospectively and evenly assigned to one of the two needle biopsy methods from April 2007 until May 2008. Two cores of renal biopsy specimen were obtained in each case and subjected to histopathological and immunoflourescence (IF examination. Pain associated with the procedure was assessed using a visual analog scale. The number of glomeruli retrieved using the 16G needle ranged from 0 to 30 (mean 9.42 ± 5.5 and those retrieved using 18G needle ranged from 0 to 19 (mean 7.72 ± 4.4, P <0.05. The quality of biopsy was poorer with 18G needle as compared with 16G needles because of a higher amount of fragmentation and crushing artifact. There was no difference in the compli-cation rates between the two needles (2% each. The 16G needle was associated with significantly more pain than the 18G needle. We conclude that our study demonstrates the benefit of the larger 16G needle in providing more tissue and glomeruli, which is more diagnostically useful. However, the use of 16G needle was associated with significantly more pain than the 18G needle, and may be a better compromise for diagnostic usefulness and patient acceptability.

  6. Diagnostic and therapeutic features associated with modification of quality-of-life's outcomes between one and six months after major surgery for head and neck cancer.

    Science.gov (United States)

    Gobbo, Margherita; Bullo, Federica; Perinetti, Giuseppe; Gatto, Annalisa; Ottaviani, Giulia; Biasotto, Matteo; Tirelli, Giancarlo

    2016-01-01

    Treatments used in head and neck cancer greatly impact the physical, psychological and functional state of patients. Evaluation of quality of life has become an integral part of the treatment. This retrospective study evaluates features involved in changes in quality of life after major surgery for head and neck cancer within six months, according to self-reported outcomes. One hundred and thirty patients completed the University of Washington Quality of Life questionnaire one and six months after major surgery for head and neck cancer. A multivariate model was used to evaluate which diagnostic and therapeutic features were related to improvement of quality of life within a six-month period. Significant improvement in most features related to quality of life was already recognizable at six months. Patients submitted to more invasive treatment had the biggest improvement in quality of life between time-points, as well as those patients with bigger tumors. After major surgery, patients may undergo fast recovery, with overall quality of life likely to improve in the short-term. Clinicians must be aware of the importance of dealing with treatment-related issues immediately after surgery, with hopeful possibility of on-the-upgrade results. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  7. Rheumatoid Arthritis Educational Video Series

    Medline Plus

    Full Text Available ... Rheumatoid Arthritis Educational Video Series Rheumatoid Arthritis Educational Video Series This series of five videos was designed ... Activity Role of Body Weight in Osteoarthritis Educational Videos for Patients Rheumatoid Arthritis Educational Video Series Psoriatic ...

  8. First Central and Eastern European Workshop on Quality control, patient dosimetry and radiation protection in diagnostic and interventional radiology and nuclear medicine

    International Nuclear Information System (INIS)

    National Frederic Joliot-Curie Research Institute for Radiobiology and Radiohygiene

    2007-01-01

    First Central and Eastern European Workshop on Quality Control, Patient Dosimetry and Radiation Protection in Diagnostic and Interventional Radiology and Nuclear Medicine, scientifically supported and accredited as a CPD event for medical physicists by EFOMP, National 'Frederic Joliot-Curie' Research Institute for Radiobiology and Radiohygiene (NRIRR), Budapest, Hungary, April 25-28, 2007. Topics of the meeting included all areas of medical radiation physics except radiation therapy. A unique possibility was realized by inviting four European manufacturers of quality control instrumentation, not only for exhibiting but they also had 45 minutes individual presentations about each manufacturer's product scale and conception. Further sessions dealt with dosimetry, optimization, quality control and testing, radiation protection and standardization, computed tomography and nuclear medicine, in 29 oral presentations and 1 poster of the participants. (S.I.)

  9. Robust Video Communication over an Urban VANET

    Directory of Open Access Journals (Sweden)

    N. Qadri

    2010-01-01

    Full Text Available Video communication within a Vehicular Ad Hoc Network (VANET has the potential to be of considerable benefit in an urban emergency, as it allows emergency vehicles approaching the scene to better understand the nature of the emergency. However, the lack of centralized routing and network resource management within a VANET is an impediment to video streaming. To overcome these problems the paper pioneers source-coding techniques for VANET video streaming. The paper firstly investigates two practical multiple-path schemes, Video Redundancy Coding (VRC and the H.264/AVC codec's redundant frames. The VRC scheme is reinforced by gradual decoder refresh to improve the delivered video quality. Evaluation shows that multiple-path 'redundant frames' achieves acceptable video quality at some destinations, whereas VRC is insufficient. The paper also demonstrates a third source coding scheme, single-path streaming with Flexible Macroblock Ordering, which is also capable of delivery of reasonable quality video. Therefore, video communication between vehicles is indeed shown to be feasible in an urban emergency if the suitable source coding techniques are selected.

  10. 61214++++','DOAJ-ART-EN'); return false;" href="+++++https://jual.nipissingu.ca/wp-content/uploads/sites/25/2014/06/v61214.m4v">61214++++">Jailed - Video

    Directory of Open Access Journals (Sweden)

    Cameron CULBERT

    2012-07-01

    Full Text Available As the public education system in Northern Ontario continues to take a downward spiral, a plethora of secondary school students are being placed in an alternative educational environment. Juxtaposing the two educational settings reveals very similar methods and characteristics of educating our youth as opposed to using a truly alternative approach to education. This video reviews the relationship between public education and alternative education in a remote Northern Ontario setting. It is my belief that the traditional methods of teaching are not appropriate in educating at risk students in alternative schools. Paper and pencil worksheets do not motivate these students to learn and succeed. Alternative education should emphasize experiential learning, a just in time curriculum based on every unique individual and the students true passion for everyday life. Cameron Culbert was born on February 3rd, 1977 in North Bay, Ontario. His teenage years were split between attending public school and his willed curriculum on the ski hill. Culbert spent 10 years (1996-2002 & 2006-2010 competing for Canada as an alpine ski racer. His passion for teaching and coaching began as an athlete and has now transferred into the classroom and the community. As a graduate of Nipissing University (BA, BEd, MEd. Camerons research interests are alternative education, physical education and technology in the classroom. Currently Cameron is an active educator and coach in Northern Ontario.

  11. Health-related quality of life, anxiety and depression in the diagnostic phase of suspected cancer, and the influence of diagnosis

    DEFF Research Database (Denmark)

    Larsen, Ellen Frøsig Moseholm; Rydahl Hansen, Susan; Overgaard, Dorthe

    2016-01-01

    Background Undergoing diagnostic evaluation for cancer has been associated with a high prevalence of anxiety and depression and affected health-related quality of life (HRQoL). The aims of this study were to assess HRQoL, anxiety, and depression pre- and post-diagnosis in patients undergoing...... patients with non-cancer diagnoses were calculated. The impact of baseline psychological, socio-demographic, and medical factors on HRQoL, anxiety and depression at follow-up was explored by bootstrapped multivariate linear regression analyses and logistic regression analyses. Results A total of 838....... There were no intra- or inter-group differences in the depression scores. The strongest predictors of global QL, anxiety, and depression after a known diagnosis were baseline scores, co-morbidity and poor self-rated health. Conclusions Patients undergoing diagnostic evaluations for cancer based on non...

  12. Fundamentals of quality assessment of molecular amplification methods in clinical diagnostics. International Federation of Clinical Chemistry Scientific Division Committee on Molecular Biology Techniques.

    Science.gov (United States)

    Neumaier, M; Braun, A; Wagener, C

    1998-01-01

    The increasing interest in molecular biology diagnostics is a result of the tremendous gain of scientific knowledge in genetics, made possible especially since the introduction of amplification techniques. High expectations have been placed on genetic testing, and the number of laboratories now using the relevant technology is rapidly increasing--resulting in an obvious need for standardization and definition of laboratory organization. This communication is an effort towards that end. We address aspects that should be considered when structuring a new molecular diagnostic laboratory, and we discuss individual preanalytical and analytical procedures, from sampling to evaluation of assay results. In addition, different means of controlling contamination are discussed. Because the methodology is in constant change, no general standards can be defined. Accordingly, this publication is intended to serve as a recommendation for good laboratory practice and internal quality control and as a guide to troubleshooting, primarily in amplification techniques.

  13. Assessing Visibility of Individual Transmission Errors in Networked Video

    DEFF Research Database (Denmark)

    Korhonen, Jari; Mantel, Claire

    2016-01-01

    Traditionally, subjective video quality is assessed by user experiments involving quality ratings, pairwise comparisons, or rank ordering, based on the overall impression of quality. Less attention has been paid on assessing the visibility of individual defects. However, many practical applications...

  14. Celiac Family Health Education Video Series

    Medline Plus

    Full Text Available ... Us Giving to Boston Children's Newsroom Quality and Patient Safety Research + Innovation Videos Contact Us Boston Children's Hospital 300 Longwood Avenue, Boston, MA 02115 For Patients: 617-355-6000 For Referring Providers: 844-BCH- ...

  15. Celiac Family Health Education Video Series

    Medline Plus

    Full Text Available ... Back to School Programs Healthful Living Injuries and Safety More Boston Children's Hospital #1 Ranked Children’s Hospital ... Giving to Boston Children's Newsroom Quality and Patient Safety Research + Innovation Videos Contact Us Boston Children's Hospital ...

  16. Emergency CT brain: preliminary interpretation with a tablet device: image quality and diagnostic performance of the Apple iPad.

    LENUS (Irish Health Repository)

    Mc Laughlin, Patrick

    2012-04-01

    Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.

  17. Next generation quality: Assessing the physician in clinical history completeness and diagnostic interpretations using funnel plots and normalized deviations plots in 3,854 prostate biopsies

    Directory of Open Access Journals (Sweden)

    Michael Bonert

    2017-01-01

    Full Text Available Background: Observational data and funnel plots are routinely used outside of pathology to understand trends and improve performance. Objective: Extract diagnostic rate (DR information from free text surgical pathology reports with synoptic elements and assess whether inter-rater variation and clinical history completeness information useful for continuous quality improvement (CQI can be obtained. Methods: All in-house prostate biopsies in a 6-year period at two large teaching hospitals were extracted and then diagnostically categorized using string matching, fuzzy string matching, and hierarchical pruning. DRs were then stratified by the submitting physicians and pathologists. Funnel plots were created to assess for diagnostic bias. Results: 3,854 prostate biopsies were found and all could be diagnostically classified. Two audits involving the review of 700 reports and a comparison of the synoptic elements with the free text interpretations suggest a categorization error rate of 40 cases and together assessed 3,690 biopsies. There was considerable inter-rater variability and a trend toward more World Health Organization/International Society of Urologic Pathology Grade 1 cancers in older pathologists. Normalized deviations plots, constructed using the median DR, and standard error can elucidate associated over- and under-calls for an individual pathologist in relation to their practice group. Clinical history completeness by submitting medical doctor varied significantly (100% to 22%. Conclusion: Free text data analyses have some limitations; however, they could be used for data-driven CQI in anatomical pathology, and could lead to the next generation in quality of care.

  18. Design and evaluation of a unique RT-qPCR assay for diagnostic quality control assessment that is applicable to pathogen detection in three species of salmonid fish.

    Science.gov (United States)

    Sepúlveda, Dagoberto; Bohle, Harry; Labra, Alvaro; Grothusen, Horst; Marshall, Sergio H

    2013-09-16

    The detection of pathogens at early stages of infection is a key point for disease control in aquaculture. Therefore, accurate diagnostic procedures are a must. Real-time PCR has been a mainstay in diagnostics over the years due to its speed, specificity, sensitivity, reproducibility and throughput; as such, real-time PCR is a target for improvement. Nevertheless, to validate a novel diagnostic tool, correct setup of the assay, including proper endogenous controls to evaluate the quantity and quality of the samples and to detect possible sample degradation, is compulsory. This work aims to design a unique RT-qPCR assay for pathogen detection in the three salmonid species reared in Chile. The assay uses elongation factor 1 alpha as the single endogenous control, thus avoiding the need for multiple endogenous controls, as well as multiple validations and non-comparable quality control parameters. The in vivo and in vitro analyses of samples from Salmo salar, Oncorhynchus mykiss and Oncorhynchus kisutch showed that when primers were accurately selected to target conserved regions of the elongation factor 1 alpha (ELF1α) gene, a single novel RT-qPCR assay yielding similar and reproducible Ct values between the three species could be designed. The opposite occurred when an assay originally designed for Salmo salar was tested in samples from the two species of the genus Oncorhynchus. Here, we report the design and evaluation of an accurate trans-species RT-qPCR assay that uses the elongation factor 1 alpha (ELF1α) gene as an endogenous control and is applicable for diagnostic purposes in samples obtained from the three salmonid species reared in Chile.

  19. A system for endobronchial video analysis

    Science.gov (United States)

    Byrnes, Patrick D.; Higgins, William E.

    2017-03-01

    Image-guided bronchoscopy is a critical component in the treatment of lung cancer and other pulmonary disorders. During bronchoscopy, a high-resolution endobronchial video stream facilitates guidance through the lungs and allows for visual inspection of a patient's airway mucosal surfaces. Despite the detailed information it contains, little effort has been made to incorporate recorded video into the clinical workflow. Follow-up procedures often required in cancer assessment or asthma treatment could significantly benefit from effectively parsed and summarized video. Tracking diagnostic regions of interest (ROIs) could potentially better equip physicians to detect early airway-wall cancer or improve asthma treatments, such as bronchial thermoplasty. To address this need, we have developed a system for the postoperative analysis of recorded endobronchial video. The system first parses an input video stream into endoscopic shots, derives motion information, and selects salient representative key frames. Next, a semi-automatic method for CT-video registration creates data linkages between a CT-derived airway-tree model and the input video. These data linkages then enable the construction of a CT-video chest model comprised of a bronchoscopy path history (BPH) - defining all airway locations visited during a procedure - and texture-mapping information for rendering registered video frames onto the airwaytree model. A suite of analysis tools is included to visualize and manipulate the extracted data. Video browsing and retrieval is facilitated through a video table of contents (TOC) and a search query interface. The system provides a variety of operational modes and additional functionality, including the ability to define regions of interest. We demonstrate the potential of our system using two human case study examples.

  20. Video Design Games

    DEFF Research Database (Denmark)

    Smith, Rachel Charlotte; Christensen, Kasper Skov; Iversen, Ole Sejer

    We introduce Video Design Games to train educators in teaching design. The Video Design Game is a workshop format consisting of three rounds in which participants observe, reflect and generalize based on video snippets from their own practice. The paper reports on a Video Design Game workshop...

  1. Algorithm for Video Summarization of Bronchoscopy Procedures

    OpenAIRE

    Leszczuk, Miko?aj I; Duplaga, Mariusz

    2011-01-01

    Abstract Background The duration of bronchoscopy examinations varies considerably depending on the diagnostic and therapeutic procedures used. It can last more than 20 minutes if a complex diagnostic work-up is included. With wide access to videobronchoscopy, the whole procedure can be recorded as a video sequence. Common practice relies on an active attitude of the bronchoscopist who initiates the recording process and usually chooses to archive only selected views and sequences. However, it...

  2. Digital video for the desktop

    CERN Document Server

    Pender, Ken

    1999-01-01

    Practical introduction to creating and editing high quality video on the desktop. Using examples from a variety of video applications, benefit from a professional's experience, step-by-step, through a series of workshops demonstrating a wide variety of techniques. These include producing short films, multimedia and internet presentations, animated graphics and special effects.The opportunities for the independent videomaker have never been greater - make sure you bring your understanding fully up to date with this invaluable guide.No prior knowledge of the technology is assumed, with explanati

  3. Rare Disease Video Portal

    OpenAIRE

    Sánchez Bocanegra, Carlos Luis

    2011-01-01

    Rare Disease Video Portal (RD Video) is a portal web where contains videos from Youtube including all details from 12 channels of Youtube. Rare Disease Video Portal (RD Video) es un portal web que contiene los vídeos de Youtube incluyendo todos los detalles de 12 canales de Youtube. Rare Disease Video Portal (RD Video) és un portal web que conté els vídeos de Youtube i que inclou tots els detalls de 12 Canals de Youtube.

  4. Scalable video on demand adaptive Internet-based distribution

    CERN Document Server

    Zink, Michael

    2013-01-01

    In recent years, the proliferation of available video content and the popularity of the Internet have encouraged service providers to develop new ways of distributing content to clients. Increasing video scaling ratios and advanced digital signal processing techniques have led to Internet Video-on-Demand applications, but these currently lack efficiency and quality. Scalable Video on Demand: Adaptive Internet-based Distribution examines how current video compression and streaming can be used to deliver high-quality applications over the Internet. In addition to analysing the problems

  5. Enhancement system of nighttime infrared video image and visible video image

    Science.gov (United States)

    Wang, Yue; Piao, Yan

    2016-11-01

    Visibility of Nighttime video image has a great significance for military and medicine areas, but nighttime video image has so poor quality that we can't recognize the target and background. Thus we enhance the nighttime video image by fuse infrared video image and visible video image. According to the characteristics of infrared and visible images, we proposed improved sift algorithm andαβ weighted algorithm to fuse heterologous nighttime images. We would deduced a transfer matrix from improved sift algorithm. The transfer matrix would rapid register heterologous nighttime images. And theαβ weighted algorithm can be applied in any scene. In the video image fusion system, we used the transfer matrix to register every frame and then used αβ weighted method to fuse every frame, which reached the time requirement soft video. The fused video image not only retains the clear target information of infrared video image, but also retains the detail and color information of visible video image and the fused video image can fluency play.

  6. Turning an Urban Scene Video into a Cinemagraph

    OpenAIRE

    Yan, Hang; Liu, Yebin; Furukawa, Yasutaka

    2016-01-01

    This paper proposes an algorithm that turns a regular video capturing urban scenes into a high-quality endless animation, known as a Cinemagraph. The creation of a Cinemagraph usually requires a static camera in a carefully configured scene. The task becomes challenging for a regular video with a moving camera and objects. Our approach first warps an input video into the viewpoint of a reference camera. Based on the warped video, we propose effective temporal analysis algorithms to detect reg...

  7. Quality control procedures of dental diagnostic radiology systems; Elaboracao de um procedimento para controle de qualidade em sistemas de radiodiagnostico odontologico

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Paula Serra Sasaki

    2007-07-01

    This work presents quality control reference procedures for dental diagnostic radiology systems, following the recommendations of the Publication 453 of the Brazilian Health Ministry (PF453), to be applied in dental clinics, in order to achieve an improvement in the radiological image qualities and the patient dose reduction. All tests were applied in an intraoral X rays system, following the methodology developed and the requirements of the PF 453. In order to verify the best quality of the image in relation to the smaller exposition time an object test was also developed in this work. The use of this object allowed the reduction of the exposition time of 0.5 seconds, the maximum value of the linear region of the characteristic curve, for 0.2 seconds. The tested X rays system showed a very good agreement with the applied procedures, detaching the reduction of the skin entrance dose using the film-holding devices. However, the size of the field increased and exceeded the maximum value of 6 cm recommended in the standard. The importance of the quality control in dental diagnostic radiology systems is essential due to the constant use of X radiation in dental clinics. The PF453 recommends the frequency of at least two years for the constancy tests. However, it is suggested that the professional, surgeon-dentist, should be responsible for the internal control of the image quality obtained from the X rays device. This can be done through monthly exposures of the object test developed in this work. (author)

  8. On the methods of determination of x-ray sources protection quality in x-ray diagnostic equipment

    International Nuclear Information System (INIS)

    Vladimirov, L.V.

    1973-01-01

    Existing procedures for assessing the quality of shielding of X-ray radiators are compared; these procedures are shown to have a number of shortcomings and to be very time-consuming. A procedure is offered in which shielding quality is tested in two stages: (1) X-ray tests aimed at determining the quality of protection of the X-ray tube unit; and (2) dosimeter tests proper. The results of measurements are compared with maximum permissible dosage rate

  9. Bangladesh Jobs Diagnostic

    OpenAIRE

    Farole, Thomas; Cho, Yoonyoung

    2017-01-01

    This Jobs Diagnostic presents the characteristics and constraints of the labor market in Bangladesh, identifies the objectives of the jobs agenda, and proposes a policy framework to progress toward them. This multisectoral diagnostic assesses the relationships between supply- and demand-side factors that interact to determine job creation, quality, and inclusion outcomes. Understanding the...

  10. Adaptive live multicast video streaming of SVC with UEP FEC

    Science.gov (United States)

    Lev, Avram; Lasry, Amir; Loants, Maoz; Hadar, Ofer

    2014-09-01

    Ideally, video streaming systems should provide the best quality video a user's device can handle without compromising on downloading speed. In this article, an improved video transmission system is presented which dynamically enhances the video quality based on a user's current network state and repairs errors from data lost in the video transmission. The system incorporates three main components: Scalable Video Coding (SVC) with three layers, multicast based on Receiver Layered Multicast (RLM) and an UnEqual Forward Error Correction (FEC) algorithm. The SVC provides an efficient method for providing different levels of video quality, stored as enhancement layers. In the presented system, a proportional-integral-derivative (PID) controller was implemented to dynamically adjust the video quality, adding or subtracting quality layers as appropriate. In addition, an FEC algorithm was added to compensate for data lost in transmission. A two dimensional FEC was used. The FEC algorithm came from the Pro MPEG code of practice #3 release 2. Several bit errors scenarios were tested (step function, cosine wave) with different bandwidth size and error values were simulated. The suggested scheme which includes SVC video encoding with 3 layers over IP Multicast with Unequal FEC algorithm was investigated under different channel conditions, variable bandwidths and different bit error rates. The results indicate improvement of the video quality in terms of PSNR over previous transmission schemes.

  11. Quality of referral: What information should be included in a request for diagnostic imaging when a patient is referred to a clinical radiologist?

    Science.gov (United States)

    G Pitman, Alexander

    2017-06-01

    Referral to a clinical radiologist is the prime means of communication between the referrer and the radiologist. Current Australian and New Zealand government regulations do not prescribe what clinical information should be included in a referral. This work presents a qualitative compilation of clinical radiologist opinion, relevant professional recommendations, governmental regulatory positions and prior work on diagnostic error to synthesise recommendations on what clinical information should be included in a referral. Recommended requirements on what clinical information should be included in a referral to a clinical radiologist are as follows: an unambiguous referral; identity of the patient; identity of the referrer; and sufficient clinical detail to justify performance of the diagnostic imaging examination and to confirm appropriate choice of the examination and modality. Recommended guideline on the content of clinical detail clarifies when the information provided in a referral meets these requirements. High-quality information provided in a referral allows the clinical radiologist to ensure that exposure of patients to medical radiation is justified. It also minimises the incidence of perceptual and interpretational diagnostic error. Recommended requirements and guideline on the clinical detail to be provided in a referral to a clinical radiologist have been formulated for professional debate and adoption. © 2017 The Royal Australian and New Zealand College of Radiologists.

  12. The FAO/IAEA External Quality Assurance Programme (EQAP) and movement towards a generic veterinary diagnostic testing laboratory accreditation scheme. Report of an FAO/IAEA consultants meeting

    International Nuclear Information System (INIS)

    2002-01-01

    FAO/IAEA support in the area of animal health is focused on enhancing the ability of regional reference laboratories and national veterinary authorities in developing countries to diagnose livestock diseases of major importance using nuclear and related technologies, and to help monitor the effectiveness of national and regional intervention strategies. This is done through provision of advice to the veterinary authorities concerning the development of appropriate sampling or research strategies coupled with FAO/IAEA-led collaborative development, adaptation, standardization, evaluation, and provision of quality-controlled enzyme-linked immunosorbent assay (ELISA) kits and the components necessary for diagnostic application of the polymerase chain reaction (PCR) techniques. Additional features of FAO/IAEA animal health support include provision of relevant laboratory equipment, training of counterpart scientists and technicians in the use of the equipment and standardized assays, and coordination of quality assurance (QA) programmes to monitor the proficiency of the assayists and help evaluate the impact of improved diagnostic capabilities. The current FAO/IAEA External Quality Assurance Programme (EQAP) for Animal Disease Diagnosis began as an effort to monitor the efficacy of mass vaccination programmes as part of the Pan African Rinderpest Campaign (PARC). Proficiency test panels, composed of 40 'unknown' serum samples, were sent to participating laboratories yearly to measure their abilities with ELISA in distinguishing between samples that were positive or negative for rinderpest antibodies. From this beginning, the EQAP has grown into an effort to measure general and specific components of FAO/IAEA counterparts' QA systems and provide assurance to outside observers that the use of FAO/IAEA diagnostic ELISA's are within established control limits and the test results and diagnostic interpretations are reliable. A major objective of the current EQAP is to

  13. Evaluation of the quality of the mammography study in the radio-diagnostic service of the National Cancer Institute

    International Nuclear Information System (INIS)

    Rubio Laverde, Alba Lucia; Pineros Petersen, Marion; Betancourt Gil, Claudia

    2003-01-01

    The development of mammography quality control programs at radiology services has had an important progress in the last decades, mainly in developed countries. Although breast cancer is one of the leading causes of cancer mortality and incidence in Colombia, quality control programs for mammography screening are just beginning to be considered. This article describes the results of a baseline evaluation aimed at establishing a quality control program at the Radiology Unit of the National Cancer Institute, in Colombia. The mammography equipment, the film processing, and all main physical parameters were checked and compared to international standards. Quality of the image in 301 mammographic X-ray plates was evaluated. In order to implement a good quality control program, the need for acquiring essential instruments, improving physical facilities and starting a continuous training program is imperative

  14. Computerized method for evaluating diagnostic image quality of calcified plaque images in cardiac CT: Validation on a physical dynamic cardiac phantom

    International Nuclear Information System (INIS)

    King, Martin; Rodgers, Zachary; Giger, Maryellen L.; Bardo, Dianna M. E.; Patel, Amit R.

    2010-01-01

    Purpose: In cardiac computed tomography (CT), important clinical indices, such as the coronary calcium score and the percentage of coronary artery stenosis, are often adversely affected by motion artifacts. As a result, the expert observer must decide whether or not to use these indices during image interpretation. Computerized methods potentially can be used to assist in these decisions. In a previous study, an artificial neural network (ANN) regression model provided assessability (image quality) indices of calcified plaque images from the software NCAT phantom that were highly agreeable with those provided by expert observers. The method predicted assessability indices based on computer-extracted features of the plaque. In the current study, the ANN-predicted assessability indices were used to identify calcified plaque images with diagnostic calcium scores (based on mass) from a physical dynamic cardiac phantom. The basic assumption was that better quality images were associated with more accurate calcium scores. Methods: A 64-channel CT