Distribuição de imagens médicas via web: um servidor e cliente Dicom

Objective To evaluate the teaching effects of case introduced method based on pic- ture archiving and communication system （ PACS ） system in medical imaging course. Methods Totally 148 students （ 2009 grade ） majored in five-year clinical medicine from Xiangya Medical College were divided into 10 groups; the 10 groups were taken randomly as control group （ n=75 ） and experimental group （ n=73 ）. Control group used traditional teaching methods （ film teaching ） while experimental group used case introduced method based on PACS system. Effects of teaching between were evaluated by questionnaire and test. χ^2 test was used to compare students＇ theoretical test scores, with α level = 0.05. Results Based on results of questionnaires, more students in experimental group than in control group hold that case introduced method based on PACS system can achieve the purpose of teaching, improve interests in learning, and strengthen the mastery of knowledge. Test scores showed that the percentage of students scored 90-100 and 80-89 （ respectively 14%, 75% ） in experimental group was significantly higher than that in control group （respectively 5%, 66% ） （χ^2 =17.932, P=O.O00 ）. Conclusions Application of case introduced method based on PACS system in medical imaging course not only improve students＇ motivation to learn and their clinica~ ability-, but also allow teachers to find and correct short- comings of students timely, therefore, it is worth promoting. Key words: Picture archiving and communication system; Case introduced method; Prac-tice teaching

Diagnostic tools supported by digital medical images have increasingly become an essential aid to medical decisions. However, despite its growing importance, Picture Archiving and Communication Systems (PACS) are typically oriented to support a single healthcare institution, and the sharing of medical data across institutions is still a difficult process. This paper describes a proposal to publish and control Digital Imaging Communications in Medicine (DICOM) services in a wide domain composed of several healthcare institutions. The system creates virtual bridges between intranets enabling the exchange, search and store of the medical data within the wide domain. The service provider publishes the DICOM services following a token-based strategy. The token advertisements are public and known by all system users. However, access to the DICOM service is controlled through a role association between an access key and the service. Furthermore, in medical diagnoses, time is a crucial factor. Therefore, our system is a turnkey solution, capable of exchanging medical data across firewalls and Network Address Translation (NAT), avoiding bureaucratic issues with local network security. Security is also an important concern - in any transmission across different domains, data is encrypted by Transport Layer Security (TLS).

In recent years, Picture Archiving and Communications Systems have begun to proliferate in the medical community. This is a result of technical advances that have occurred in two areas — advances in computer technology (such as storage density, processing speeds, network bandwidth, compression techniques, and so on), and the maturation of robust standards for communication and transmission of medical images and information (Standards like HL‐7, DICOM, and IHE). In parallel with these developments, the medical imaging equipment and information systems vendors have been developing robust software implementations and more advanced system architecture to take advantage of this emerging technology and these robust standards. As a result of this revolutionary change in the way we operate, it has become increasingly important that we in the Medical Physics community modify our approach to the type of support we bring to these operations accordingly. This presentation will focus on some of the issues the Medical Physicist is likely to face when supporting a clinical operation that is undergoing (or is about to undergo) a conversion from film‐screen base radiography to digitally acquired images. It will cover the educational needs of the Medical Physicist, radiologists and technical staff, how to use photostimulable phosphor imaging to introduce a radiology department to digital imaging, the importance of Modality Work List Management in the filmless radiology environment, selection of a DDR system for clinical use, weaning the referring clinicians off of film and what issues are important to achieving this, quality control programs for digital imaging systems, and finally those features of the radiology reading room environment that are important for soft‐copy interpretation.

Devices that acquire digital medical images using radiation (DR; Digital Radiography) are widely used in medical institutions to obtain information necessary for patient diagnosis, and the frequency of use is gradually increasing. By selecting 3 hospitals that perform more than 50 digital X-ray medical imaging tests per day, and by installing a glass dosimeter for environmental measurement on the outside of the examination room protection wall, entrance door, and patient viewing window, the leakage radiation dose was measured for one month from May 16, 2021 to June 21, 2021, then it was analyzed by converting into a 3-month cumulative dose. The cumulative dose equivalent of 1 cm in the glass dosimeter for 3 months outside the shielding wall at the entrance of the digital medical image acquisition radiation generating device examination room was 0.96 mSv, and the average value was 0.18 mSv. In addition, the cumulative 1 cm dose equivalent value of the glass dosimeter for 3 months outside the shielding wall on the control room side showed a maximum of 3.03 mSv and an average of 0.41 mSv. The glass dosimeter cumulative dose 1cm dose equivalent value was up to 8.31 mSv and averaged 2.09 mSv for 3 months outside the door of the patient waiting room of the digital medical image acquisition radiation generating device examination room. In addition, the glass dosimeter cumulative dose 1cm dose equivalent value for 3 months outside the control room door showed a maximum of 14.04 mSv and an average of 3.84 mSv. These research results are expected to be widely used in setting measurement methods and regulatory standards for environmental radiation safety management of medical radiation generators, and continuous research management at the national level is suggested.

At present the management of radiological information is done manually in most hospitals. Images from the digital modalities (e.g. Computer- tomography scanners, X-ray machines) are converted into films and stored in a room. These films are then distributed manually and interpretation is done by reading the films through light boxes. With the advances in semiconductor technology and digital processing techniques it is now possible to automate these operations by using a digital system for archiving and communication of images. A Picture Archiving and Communication System (PACS), is a digital system for acquiring, storing, moving and displaying picture or image information .These systems are highly dependent on the new technology for mass storage of data on optical disks. In the medical environment, the ultimate goal of using digital images and PACS is tohave a radiology department without filmjackets 2,3 A typical PACS consists of a database of medical images, display stations, acquisition systems and the communications medium. There are two possible architectures for PACS, one is the distributed PACS where all the modules are linked together through a high speed communication medium, and the other is a centralized PACS where the acquisition nodes and the display stations are part of the system which comprises the image database 4. In this paper we present analytical queueing models of distributed PACS used in the medical environments. These models are for the image database, the picture viewing stations, and the communication channels.

Medical images stored in a hospital system are generally confidential and integrated and require strict security. However, medical information stored on digital medical imaging systems, as well as picture archiving and communication systems (PACS), are vulnerable to attack when the data are transferred over wireless or wired communication networks. To solve this problem, a watermarking algorithm for medical images is proposed using a bit threshold map based on just noticeable distortion (JND) in the discrete cosine transform (DCT) method. The low-frequency component comprises a considerable amount of the signal energy for most images. As a result, it has a crucial effect on the image quality. Therefore, in this paper, the proposed algorithm embeds watermarks based on the low-frequency components of the image, such as the DC coefficient of the DCT. When watermarks are embedded in a low frequency area, the subjective image quality is often degraded. To compensate for the degradation of the imperceptibility of the watermarking system, which results from embedding watermarks in the low-frequency component, this research considers the human visual system. In addition, the embedding strength of the JND value is used to improve the watermarking imperceptibility. We applied the proposed watermarking algorithm to a variety of medical images using a computer simulation. The algorithm's performance was verified using a variety of attacks for eliminating watermarks. The simulation results show that the proposed algorithm robustly provides protection against a variety of possible attacks.

The trend in biomedical imaging is increasingly digital and multimedia oriented. Medical image management was destined to play a central role in clinical information systems design and construction. The purpose of this chapter is to introduce the field of digital medical image management and the component of picture archiving and communication systems (PACS). The development of PACS has resulted in a unified infrastructure for management of acquisition, archiving, communication, and display of multimodality image data. However, PACS has not yet provided sufficient flexibility to allow efficient sharing and utilization of image-related information. The new wave of technology, image database management, has the potential to change the practice, education, and research of biomedical imaging and to improve the efficiency of healthcare delivery in the coming decades.

Picture archiving and communication systems (PACS) is a current research topic in both the United States and Japan. During the past 6 years, our department has been working in this field very closely with our colleagues in Japan. In July 1 986, we attended the Third International Symposium on Picture Archiving and Communication Systems/Personal Health Data Recording Systems (JPACS) in conjunction with the Fifth Symposium on Medical Imaging and Technology (JAMIT) at the National Cancer Center in Tokyo. After the meeting, we visited various PACS research and development laboratories at major imaging manufacturers and hospitals. We summarized our impressions in a commentary: “Picture Archiving and Communication Systems in Japan” [1 ]. Since then, we have successfully implemented two PACS modules, one in the pediatric radiology section and one in the coronary care unit [2, 3]. More than 200 visitors from Japan have come to see our facilities. Among these visitors was Professor T. Takahasi from Kyoto University Hospital, who was the program chairman of the Eighth Symposium of JAMIT/Sixth International Symposium on PACS in July 1 989. After his visit, he extended an invitation to us to give the keynote speech, “Recent Progress in PACS” for the meeting. We took this opportunity to go back to Japan and repeat the hospital and laboratory tour in order to observe their research and development progress in PACS during the past 3 years. This paper is a summary of our opinion ofthe changes that have occurred in Japan since our last visit of the status of PACS in that country compared with that in ours. The JAMIT Meeting and the JPACS Meeting

Watermarking, as a new technology, has been applied widely in medical images field for its advantages. This paper emphasizes on these works as follows: firstly analyzes the secure requirements of medical images and watermarking functions from the practical applications view, and then reviews some typical algorithms of the existing watermarking and presents a universal evaluating scheme for medical digital images watermarking, finally, some further works are proposed. The purpose for this paper is to study the present watermarking methods and promote the new schemes emergence effectively.

PACS and Web-based image distribution and display

Medical Images has evolved from time to time and the need to protect sensitive information related to such images have also grown significantly. Nowadays data being the primary asset of an individual, protecting them has posed new challenges from time and again. With the advancement of the digital medium, the medical image has been at greater risk and there is an urgent need to protect the information and the raw pixel data of such images. This research focuses on ensuring the confidentiality of DICOM medical images and protecting the Electronic Patient Report (EPR) by applying both cryptographic and steganographic protection techniques. The encryption keys are generated using the Logistic Chaotic Map and Non-Linear Feedback Shift Register. the electronic patient report (EPR) is converted into a 9-space-format using Continued Fraction of Ramanujan conjecture and then using steganography techniques EPR is embedded into the Most Significant Bits of Medical Images. The final encrypted image contains the EPR as well as encrypted medical image. The key sequence used in order to encrypt the medical image is highly pseudo random and the Key Space Analysis depicted that the algorithm is very strong. This work has paved a better way of securely storing 16-bit DICOM medical images and EPR into the Picture Archive and Communication System repository. The proposed security model has shown promising results in comparison to other research and the various analysis did show significant improvements over past studies.

The picture archiving and communication system (PACS) originated as an image management system for improving the efficiency of radiologic practices. It has evolved into a hospital-integrated system that stores information media in many forms, including voice, text, medical records, waveform images, and video recordings. The integration of these various types of information requires the technology of multimedia, including hardware platforms, information systems and databases, communication protocols, display technology, and system interfacing and integration. The purpose of this book is to discuss the conceptual and technologic advances in PACS development for all of these previously mentioned technologies. The book also emphasizes the growing field of PACS-based imaging informatics, where existing PACS resources are used for largescale horizontal and longitudinal clinical service, research, and education applications. The book is intended for those who are involved in a health care environment that manages the everyday practical realities of PACS planning, operation, and maintenance. The book will also serve as excellent curriculum material for the training of PACS information technology personnel because the author provides comprehensive concepts that tie medical imaging, medical physics, information technology, and clinical workflow with enterprise PACS (multiple, hospital-wide PACS). The author, H. K. Huang, has been involved in PACS development since the 1980s and is a leading scientist in the field. The book is divided into five parts and 23 chapters. Part 1, titled “Medical Imaging Principles,” summarizes the history of PACS, the fundamental concepts of digital medical imaging, and the different types of modalities integrated into PACS. Part 2, titled “PACS Fundamentals,” describes in detail the PACS subsystems and industry standards (Digital Imaging and Communications in Medicine and Health Level 7) that are used to integrate PACS with the hospital information system and radiology information system. Part 3, titled “PACS Operation,” describes the practical problems encountered by PACS administrators and users and discusses different techniques to solve these problems, with many examples from installed PACS sites around the world. Because the author developed PACS at the University of California, Los Angeles, in 1991 and the University of California, San Francisco, in 1995, he is able to draw from his expertise on the subject. The author also uses his experience from developing many state-of-theart prototypes (eg, fault tolerant storage system) funded by research grants. Part 4, titled “PACS-based Imaging Informatics,” presents image-processing techniques that can be used to mine the huge image and clinical data resources stored in the PACS archive. The analysis of lung nodules by using temporal computed tomographic and contentbased image indexing are some of the examples of advanced processing applications applied to PACS data mining. Part 5, titled “Enterprise PACS,” describes different models for implementing an enterprise PACS in terms of the architectural design of the system and financial and business models. This new book builds on two previous volumes on PACS that were written by the author. The text, image collections, and schematic diagrams in this current work achieve the author’s goal of providing up-to-date material concerning the technologic advances in PACS and imaging informatics. The text serves as a guide for those who are planning an enterprise PACS and provides teaching material for training PACS developers in industry and health care. The author has used portions of this book as lecture material for graduate courses at leading universities in the United States and abroad. The author also uses many examples to emphasize that the integration of heterogeneous health care information systems is becoming more complex and that, as more radiologists and clinicians expect higher standards in the reliability of the data, a systemic understanding of Digital Imaging and Communications in Medicine, Health Level 7, and Integrating the Healthcare Enterprise becomes ever more important to optimize enterprise workflow. The strength of the book lies in the vast experience that the author, who has implemented PACS at numerous institutions in the United States and abroad, has transmitted into this new book. Huang has conducted first-hand analysis of the various systems from PACS manufacturers that are used in clinical operation at large medical institutions and has performed up-to-date research in data mining of the huge image and data resources stored in the PACS repository.

In the modern globe, digital medical image processing is a major branch to study in the fields of medical and information technology. Every medical field relies on digital medical imaging in diagnosis for most of their cases. One of the major components of medical image analysis is medical image segmentation. Medical image segmentation participates in the diagnosis process, and it aids the processes of other medical image components to increase the accuracy. In unsupervised methods, fuzzy c-means (FCM) clustering is the most accurate method for image segmentation, and it can be smooth and bear desirable outcomes. The intention of this study is to establish a strong systematic way to segment complicate medical image cases depend on the proposed method to share in the decision-making process. This study mentions medical image modalities and illustrates the steps of the FCM clustering method mathematically with example. It segments magnetic resonance imaging (MRI) of the brain to separate tumor inside the brain MRI according to four statuses.

INTRODUCTION: The Iraqi healthcare sector faces significant challenges in the management of medical images, leading to diagnostic delays and increased error rates. Picture Archiving and Communication Systems (PACS) are essential for improving workflow and patient care, yet their implementation in Iraq remains limited and underexplored.OBJECTIVES: This study aims to identify the essential user requirements and major obstacles for implementing PACS in Iraqi hospitals, and to propose solutions tailored to the local context.METHODS: A quantitative survey was conducted among 60 healthcare professionals to assess both functional and non-functional requirements for PACS. The survey also explored current usage, perceived barriers, and user expectations.RESULTS: Findings revealed that a significant proportion of respondents had never used PACS, highlighting the urgent need for comprehensive training and support. The main obstacles identified were high system upgrade costs, data security concerns, and slow image retrieval times. The study set specific goals: to improve image retrieval speed by at least 40%, ensure 95% data security, increase user satisfaction by 75%, address at least three major usability challenges, and develop and test a PACS prototype in two hospital departments.CONCLUSION: The research recommends the development of a customised PACS solution for Iraq, addressing the unique needs of the healthcare environment. These findings provide a foundation for future digital health initiatives, aiming to enhance healthcare quality, reduce diagnostic errors, and improve operational efficiency in Iraqi hospitals.

The recent introduction of the High Efficiency Video Coding (HEVC) standard provides opportunities to improve medical image compression in picture archiving and communications systems. In this paper, we propose improvements to the HEVC intra coding process for lossless compression of grayscale anatomical medical images, which are characterized by their large amount of edges. Specifically, we propose alternative angular and planar prediction modes that are based on sample-wise differential pulse code modulation (DPCM) with an increased range of directionalities. We also propose an implementation of the DPCM decoding process that maintains the block-wise coding structure of HEVC. Evaluation results on various medical images show that the proposed DPCM modes efficiently predict the large amount of edges in these images achieving bit-rate savings of up to 15%.