Image Data Transfer Research Articles

Integrating the Management of Patient Three-Dimensional Treatment Planning and Image Data.

The management of data for three-dimensional conformal radiation therapy (3D CRT) is a multifaceted enterprise that includes image data transfer and format conversion, the safeguarding and distribution of treatment planning data, and the construction of efficient and secure user environments. Because 3D radiation therapy is so closely tied to computational methods for processing and presenting images, attention to these issues is essential for developing practical systems for 3D CRT.

Commentary on “Diagnosis of Alzheimer's disease: Two decades of progress.” Central role of technology in the treatment and prevention of Alzheimer's disease

Commentary on “Diagnosis of Alzheimer's disease: Two decades of progress.” Central role of technology in the treatment and prevention of Alzheimer's disease

Initiation of a teleradiotherapeutic network for patients in German lymphoma studies

PurposeDeviations of radiation treatment portals and dose from prospective treatment plans are unfavorable prognostic factors for lymphoma patients. Therefore, an extensive radiotherapy quality assurance program is used in the ongoing German lymphoma studies. The introduction of teleradiotherapy offered the opportunity to optimize and simplify the workflow of these quality assurance programs. The purpose of this report was to evaluate the feasibility of teleradiotherapy and to describe our experiences with these innovative tools. Methods and materialsDuring this pilot phase, five radiotherapy centers were equipped with the hardware and software that guarantees a rapid and high-quality transfer of imaging data, as well as real-time teleconferences. The workstation consists of standard PCs with Windows NT as the operating system and the commercial telemedicine software Hipax. ResultsAs a first step, imaging communication between the radiotherapy reference centers in Cologne and Homburg/Saar was established. Subsequently, three additional radiotherapy departments (Universities of Berlin, Münster, and Munich) with large numbers of lymphoma patients were connected. Other study centers delivered digital imaging on mobile data carriers or via an Integrated Services Digital Network point-to-point connection. Communication units were completed for interactive teleconferences. A facility for central online documentation was installed. Telemedical functions were integrated into the ongoing radiotherapy quality assurance program. Since the introduction of a teleradiotherapeutic workstation in the radiotherapy reference center in Cologne in January 2001, the images of 10% (n = 228 patients) of all reviewed cases of the ongoing Hodgkin's disease 10–12 trials were delivered digitally. The amount of digitally available imaging is continuously increasing. ConclusionThe introduction of teleradiotherapy improved the dialog between the radiotherapy reference centers and study centers and thus contributed toward high radiotherapy quality for lymphoma patients in Germany.

라인 스캔 카메라를 위한 고속 영상 처리 시스템 설계

In this paper, we designed an image processing system for the high speed line-scan camera which adopts the new memory model we proposed. As a resolution and a data rate of the line-scan camera are becoming higher, the faster image processing systems are needed. But many conventional systems are not sufficient to process the image data from the line-scan camera during a very short time. We designed the memory controller which eliminates the time for transferring image data from the line-scan camera to the main memory with high-speed SRAM and has a dual-port configuration therefore the DSP can access the main memory even though the memory controller are writing the image data. The memory controller is implemented by VHDL and Xilinx SPARTAN-IIE FPGA.

USB 인터페이스를 이용한 LCD 구동회로의 FPGA 설계

본 논문에서는 USB(Universal Serial Bus) 인터페이스를 이용하여 Gray Mode Graphic STN LCD를 구동하는 구동회로를 제안한다. 제안된 구동회로는 사용자가 PC상에서 작업한 이미지 데이터를 USB 인터페이스를 이용하여 LCD로 전송할 수가 있다. 따라서 기존의 방식과는 달리 마이크로프로세서를 사용하지 않기 때문에 사용자가 손쉽게 LCD를 구동할 수 있는 장점이 있다. 제안한 LCD 구동회로 부분은 VHDL(VHSIC Hardware Description Language)로 설계하여 시뮬레이션을 수행하고 ALTERA사의 EPF10K10TC144-3 FPGA를 사용하여 구현하였다. USB 인터페이스 부분은 MS-Visual C++ 6.0으로 프로그래밍하였다. 한편, 제안한 구동회로를 테스트 보드를 구성한 후에 하드웨어 동작 검증을 수행하여 그 효용성을 입증하였다. 본 논문에서 제안한 구동회로를 현재 시판중인 마이크로프로세서를 사용하는 타 업체의 구동회로와 비교한 결과는 구동회로의 작동 편이성, 제작시 소요되는 비용 등에서 우수함을 나타내었다. This paper describes a Gray Mode Graphic STN LCD drive circuit using USB interface. The drive circuit using USB interface can highly transfer image data created under PC t LCD. Hence, the LCD drive circuit doesn't use microprocessor for the convenience of users. The proposed LCD drive circuit part have been verified by simulation and by ALTERA EPF10K10TC144-3 FPGA implementation in VHDL. The USB interface part have been programmed in MS-Visual C++ 6.0. The validity and efficiency of the proposed LCD drive circuit have been verified by test board. After comparing this LCD drive circuit to specify it was verified that the developed LCD drive circuit showed good performances, such as convenience of users, low cost.

Medical diagnostic ultrasound system and method

The preferred embodiments described herein provide a medical diagnostic ultrasound imaging system and method in which a non-real-time operating system is used to transfer image data. In one preferred embodiment, a medical diagnostic ultrasound imaging system includes a central processing unit (“CPU”) located outside of the received signal path to transfer image data. The non-real-time operating system can be used, for example, to transfer image data from a hard disk to system memory for display, to transfer image data from system memory to the hard disk for storage, or to scroll image data to view a loop of image data.

A JAVA-based DICOM server with integration of clinical findings and DICOM-conform data encryption

The transfer of large amounts of medical data within heterogeneous hard and software infrastructures and the exploitation of distributed resources require a fast, secure, and platform-independent data exchange. To avoid costly vendor-specific solutions, a DICOM server was implemented in JAVA. Data access was enabled via internet browser technology. Relevant patient and image acquisition information was extracted from the DICOM images and stored into a relational database. Patient information such as radiological findings were transferred from the Radiological Information System into the database. Image data were accessed either by a fast preview tool or using a JAVA-based DICOM viewer. Since data security mechanisms are not yet part of the DICOM standard, a DICOM-conform encryption of sensitive patient data was implemented. The method allowed a dynamic selection of the data to be encrypted. Integrating this module into the image server enabled the fast and secure transfer of image data across insecure networks as well as long-term storage on CD-Recordables.

Implementation of a dynamic platform-independent DICOMM-server

Hospital-wide image and patient data transfer within heterogeneous hard- and software infrastructures can be facilitated by using standardized communication protocols and data formats such as digital imaging and communications in medicine (DICOMM). Each DICOMM application entity (AE) usually provides a static and fixed set of services according to its functionality. However, certain security concepts, changing demands of medical users, or restricted hardware capabilities may be more easily addressed by applications that dynamically provide variable subsets of DICOMM services. In a new approach, an object-oriented DICOMM server framework was developed that served as a basis for assembling various DICOMM applications. These applications may be set up dynamically to offer variable subsets of services at runtime, similar to ‘plug-ins’. The framework was designed and implemented in Java in order to provide low-cost platform-independent solutions. As an example, a DICOMM server was implemented and tested in a clinical application providing access to MR and CT images through a Java/DICOMM viewer. Data retrieval was optimized by storing parts of the image acquisition and patient data into a relational database.

Frameless Stereotactic Localization in Cranial Base Surgery

Mastery of the three-dimensional anatomic relationships of the cranial base/paranasal sinuses is required to reduce the incidence of iatrogenic surgical complications, facilitate complete tumor extirpation, and enhance functional outcomes. Real-time intraoperative localization technology is one method available to assist the cranial base surgeon. We report our institutional experience with the StealthStationtrade mark treatment guidance platform. Eighty-eight consecutive patients with pathology of the cranial base/paranasal sinuses were operated on with the aid of real-time frameless stereotactic localization. Preoperative image data sets were acquired with either CT or MRI scans. Patient demographics, accuracy of the data sets, surgical approaches, pathology, complications, and further applications of this technology are presented. Procedures were performed on 47 women and 41 men ranging in age from 6 to 85 years. In these 88 procedures, 44 MRI and 44 CT scans with a mean accuracy of 1.57 and 1.23 mm, respectively, were used. Approaches to the cranial base included midface degloving (25), endoscopic (23), craniofacial (13), maxillectomy (12), rhinotomy without maxillectomy (5), transoral (5), pterional (2), transcondylar (1), and transcervical (2). Indications for surgery included severe inflammatory disease of the paranasal sinuses with epidural or subdoral abscess, or both (7), cerebrospinal fluid fistula or encephalocele, or both (11), and 40 benign and 30 malignant tumors. Complications occurred in 10 of 88 patients (11%). Real-time intraoperative localization can be applied to cranial base surgery in a variety of scenarios. The instantaneous transfer of imaging data to the surgical field is useful in localizing pathology, enhancing operative safety, and reducing morbidity, thereby improving outcomes. This technology will certainly play an integral role in minimizing complications and improving surgical outcomes as cranial base surgery moves into the next millennium.

Development of multi-mission satellite data systems at the German Remote Sensing Data Centre

This paper focuses on conceptual aspects of the access to multi-mission remote sensing data by online catalogue and information systems. The system ISIS of the German Remote Sensing Data Centre is described as an example of a user interface to earth observation data. ISIS has been designed to support international scientific research as well as operational applications by offering online access to the database via public networks. It provides catalogue retrieval, visualisation and transfer of image data, and is integrated in international activities dedicated to catalogue and archive interoperability. Finally, an outlook is given on international projects dealing with access to remote sensing data in distributed archives.

Frameless stereotactic guided neurosurgery: clinical experience with an infrared based pointer device navigation system.

An infrared based frameless stereotactic navigation device (Easy Guide Neuro) was investigated for its clinical applicability, registration/application accuracy and limitations in a standard operating room set-up. In a five-month period 40 frameless stereotactic procedures (23 female, 17 male, mean age 46.4, yrs range 10-83) including 36 craniotomies and 4 spinal surgery procedures were performed. Image registration, data transfer and operation planning using skin fixed fiducials (between 5-10, mean 6.6) and CCT in 12 patients/MRI in 28 patients, generally was done the day before surgery. Clinical applicability was proven in all procedures with an additional time for pre-operative imaging and system application in the OR of 50 min mean (35-120 range). A useful registration was achieved in 39/40 patients (97.5%) with a registration accuracy of 3.4 mm (range 1.8-6.7) for brain surgery cases and 14.4 mm (6.8-25) for spine cases. This resulted in intra-operative application accuracy values for brain surgery of 4.2 mm mean (range 1-12). Enhanced registration/application accuracy values over the test period from 4.2/3.8 mm mean (Cases 1-20) up to 3.2/2 mm mean (Cases 21-40) was observed. In spinal surgery an application accuracy of 11.3 mm mean (range 5-20) was found. An intra-operative re-calibration because of system-head drift was necessary in none of the patients, nevertheless, application accuracy degradation due to brain shift was detected in every case. In conclusion, the system allowed a time sufficient accurate frameless intra-operative localisation guidance in cavernoma, meningioma, glioma, and brain metastasis surgery. In spinal surgery, the application accuracy exceeded clinical usefulness due to high registration inaccuracy using skin markers.

Fundamentals of videogrammetry — A review

With the advent of inexpensive and powerful CCD- (‘video-’) cameras and associated image data transfer and processing hardware novel measurement systems, based on these components, are of great potential for human movement recording. This contribution gives an introduction to the fundamentals of ‘videogrammetry’, a measurement technique based on the principles of ‘photogrammetry’. We will discuss the concept of the multi-image (more than two CCD-frames) measurement mode, the bundle adjustment with its variants for point positioning, orientation and calibration, the notions of precision and reliability, system aspects including some details on CCD-cameras and image data transfer, calibration and self-calibration, algorithms for high precision image measurements, and finally show a typical application example. Besides being a highly automated measurement technique, videogrammetry provides for high accuracy (a relative accuracy of 1: 10000 can be reached in trajectory determination with standard components) and truly real-time data processing capabilities. In addition, a great number of particles (> 100) can be measured and tracked simultaneously, and surfaces and their deformation can be determined. Therefore, the videogrammetric technique is of great interest for applications in biomechanics, sport, animation, and virtual reality generation and control.

On the Way to New Horizons: Telemedicine in Oncology

On the Way to New Horizons: Telemedicine in Oncology

Preliminary experience with medical applications of rapid prototyping by selective laser sintering

Rapid prototyping techniques, originally developed for building components from computer aided designs in the motor industry, are now being applied in medicine to build models of human anatomy from high resolution multiplanar imaging data such a computed tomography (CT). The established technique of stereolithography and the more recent selective laser sintering (SLS), both build up an object layer by layer. Models have applications in surgical planning, for the design of customised implants and for training. Preliminary experience of using the SLS technique for medical applications is described, addressing questions regarding image processing, data transfer and manufacture. Pilot models, built from nylon, included two skulls (a child with craniosynostosis and an adult with hypertelorism) and a normal femur which was modelled for use in a bioengineering test of an artificial hip. The dimensions of the models were found to be in good agreement with the CT data from which they were built—for the child's skull the difference between the model and the CT data was less than 1.0±0.5 mm in each direction. Our experience showed that, with care, a combination of existing software packages may be used for data conversion. Ideally, image data of high spatial resolution should be used. The pilot models generated sufficient clinical interest for the technique to be pursued in the orthopaedic field.

Integrating the management of patient three-dimensional treatment planning and image data

The management of data for three-dimensional conformal radiation therapy (3D CRT) is a multifaceted enterprise that includes image data transfer and format conversion, the safeguarding and distribution of treatment planning data, and the construction of efficient and secure user environments. Because 3D radiation therapy is so closely tied to computational methods for processing and presenting images, attention to these issues is essential for developing practical systems for 3D CRT.

Development and operation of PACS/teleradiology in Japan

Progress of key technologies for the past 10 years and the state of realization of PACS and teleradiology in Japan are reviewed. Even though advanced electronic technologies have brought a rapid spread of PACS and teleradiology, the total number of installations is small compared with that of the hospital information system (HIS). The reason of this is a lack of economic incentives. The merits or benefits of PACS and teleradiology have to be appreciated and paid for by reimbursement of the associated costs from health insurance companies. The progress of PACS diffusion has been very rapid for these ten years in Japan, but most systems deployed are small-sized PACS. Examples of large PACS in Japan are presented and a method for integration with the HIS and RIS (radiological information system) is described. Standardization activities on PACS such as image data transfer and filing are also introduced. A unique domestic standard in Japan for IS&C (image save and carry) and electronic filing of medical images is presented. The Japanese equivalent of the American standard DICOM is also described. Technology assessment of PACS is an important theme of study and investigation. An example of the measurement of pre- and postoperation of these systems is discussed.

Computer-assisted surgery of the paranasal sinuses with an opto-electronic stereotaxic system

A basic problem common to all systems for computer-assisted surgery (CAS) is the exact registration and referencing, that is, the transfer of preoperative image data to the intraoperative pathology. A system for computer-assisted ENT surgery should provide high precision as well as noninvasive registration and referencing. We present a system designed for such use in paranasal sinus surgery that is based on optical digitizing with several custom-made self-localizing surgical instruments. The system tracks the correct alignment of the head during CT data acquisition and continuously throughout surgery. A transformation matrix and a plane equation of the CT scan are used to match points of the object space to the image space detecting fiducial markers on the CT scans by an automatic algorithm. For position measurements a special reference frame and surgical instruments were developed and equipped with infrared light-emitting diodes that could be detected in real time. Measurements for repositioning of the reference system in a model and during real operations demonstrated a mean error ranging from 0.69 to 1.01 mm and from 0.76 to 1.67 mm respectively. Clinical experience with the application of the system for 15 patients who underwent surgery for different paranasal sinus pathologies is reported. Results suggest that the non-invasive reference system and the locatable surgical tools may be effective, accurate and useful for computer-assisted identification of intranasal structures. Such systems may contribute to further improvement of minimal invasive intranasal sinus surgery.

Which media are most likely to solve the archival problem?

The clinical application of quantitative methods for coronary arteriography remains limited, due in large part to the absence of a suitable replacement for cinefilm as the procedure record. The extension to the clinical environment of the validated objective methods which have found such widespread acceptance in clinical research studies is difficult to implement if the time-consuming and variable process for digitization of selected cinefilm frames is required. In addition, the complete integration of the angiographic procedure record with other patient records and procedures stored in a digital data format requires that the angiographic data eventually be converted to a digital format as well. Replacement of cinefilm requires that the media chosen for the task provide at least the same capabilities and preferably improved functions as those provided by cinefilm as a display, transport, and archival media. The demanding set of requirements imposed on the replacement options include high capacity, high acquisition rate, high transfer rate, application in a distributed environment, portability between institutions, and low expense. A true digital solution should also provide immediate access to the results of the angiographic procedure, transfer of image data over digital networks, multiple-user viewing capability, and quantitative analysis on a routine basis for all patients. In fact, a single media may not provide all the capabilities listed above but, rather, different media may need to be used for specialized tasks, i.e. the solution for archival may not be the same that will be employed as the portable patient record. Separation of the archival function from the acquisition/display and portable transfer functions increases the likelihood that cinefilm can be replaced in the imminent future by reducing the demands on a single media. Among the archival options available today are: (1) magnetic disks; (2) analog laser optical disks; (3) digital laser optical disks; (4) digital file-based magnetic tape; (5) digital video magnetic tape. In evaluating each of these alternatives, an accounting is required of how each meets the archival requirements along with an approximate breakdown of cost and readiness for implementation as a clinical solution today.

Performance evaluation of a picture archiving and communication network using stochastic activity networks

A fiber-optic star-based picture archiving and communication system (PACS) network that is based on a multiplexed passive star local area network with wavelength-division multiplexing (WDM) to provide separate logical channels for transfer of control and image data is discussed. The system consists of an image network (INET), for image transfer at a rate of 140 Mb/s, and a control network (CNET), operating at 10 Mb/s, for mediating the flow of image transfers. INET is a circuit switched network devoted solely to image transfer, while CNET employs the CSMA/CD protocol for bus arbitration. Stochastic activity networks were used to develop a detailed model of the command and image channels. The performance of the system was then evaluated under realistic workload conditions. In particular, a number of important performance variables, including the image response time, command channel delay, and queue length at each type of node and the network supervisor, are estimated. The results (1) show that stochastic activity networks are an appropriate model type for evaluating picture archiving and communication systems, (2) delineate the workload conditions under which PACS may effectively operate, and (3) show that even when these conditions are exceeded, the command channel load remains extremely light.

Calibration of a resonance energy transfer imaging system

A quantitative technique for the nondestructive visualization of nanometer scale intermolecular separations in a living system is described. A calibration procedure for the acquisition and analysis of resonance energy transfer (RET) image data is outlined. The factors limiting RET imaging of biological samples are discussed. Measurements required for the calibration include: (a) the spectral sensitivity of the image intensifier (or camera); (b) the transmission spectra of the emission filters; and (c) the quantum distribution functions of the energy transfer pair measured in situ. Resonance energy transfer imaging is demonstrated for two DNA specific dyes. The Förster critical distance for energy transfer between Hoechst 33342 (HO) and acridine orange (AO) is 4.5 +/- 0.7 nm. This distance is slightly greater than the distance of a single turn of the DNA helix (3.5 nm or approximately 10 base pairs), and is well below the optical diffraction limit. Timed sequences of intracellular energy transfer reveal nuclear structure, strikingly similar to that observed with confocal and electron microscopy, and may show the spatial distribution of eu- and hetero- chromatin in the interphase nuclei.