Medical imaging informatics simulators: a tutorial.

PURPOSE: A medical imaging informatics infrastructure (MIII) platform is an organized method of selecting tools and synthesizing data from HIS/RIS/PACS/ePR systems with the aim of developing an imaging-based diagnosis or treatment system. Evaluation and analysis of these systems can be made more efficient by designing and implementing imaging informatics simulators. This tutorial introduces the MIII platform and provides the definition of treatment/diagnosis systems, while primarily focusing on the development of the related simulators. METHODS: A medical imaging informatics (MII) simulator in this context is defined as a system integration of many selected imaging and data components from the MIII platform and clinical treatment protocols, which can be used to simulate patient workflow and data flow starting from diagnostic procedures to the completion of treatment. In these processes, DICOM and HL-7 standards, IHE workflow profiles, and Web-based tools are emphasized. From the information collected in the database of a specific simulator, evidence-based medicine can be hypothesized to choose and integrate optimal clinical decision support components. Other relevant, selected clinical resources in addition to data and tools from the HIS/RIS/PACS and ePRs platform may also be tailored to develop the simulator. These resources can include image content indexing, 3D rendering with visualization, data grid and cloud computing, computer-aided diagnosis (CAD) methods, specialized image-assisted surgical, and radiation therapy technologies. RESULTS: Five simulators will be discussed in this tutorial. The PACS-ePR simulator with image distribution is the cradle of the other simulators. It supplies the necessary PACS-based ingredients and data security for the development of four other simulators: the data grid simulator for molecular imaging, CAD-PACS, radiation therapy simulator, and image-assisted surgery simulator. The purpose and benefits of each simulator with respect to its clinical relevance are presented. CONCLUSION: The concept, design, and development of these five simulators have been implemented in laboratory settings for education and training. Some of them have been extended to clinical applications in hospital environments.

MIDG-Emerging grid technologies for multi-site preclinical molecular imaging research communities.

PURPOSE: Molecular imaging is the visualization and identification of specific molecules in anatomy for insight into metabolic pathways, tissue consistency, and tracing of solute transport mechanisms. This paper presents the Molecular Imaging Data Grid (MIDG) which utilizes emerging grid technologies in preclinical molecular imaging to facilitate data sharing and discovery between preclinical molecular imaging facilities and their collaborating investigator institutions to expedite translational sciences research. Grid-enabled archiving, management, and distribution of animal-model imaging datasets help preclinical investigators to monitor, access and share their imaging data remotely, and promote preclinical imaging facilities to share published imaging datasets as resources for new investigators. METHODS: The system architecture of the Molecular Imaging Data Grid is described in a four layer diagram. A data model for preclinical molecular imaging datasets is also presented based on imaging modalities currently used in a molecular imaging center. The MIDG system components and connectivity are presented. And finally, the workflow steps for grid-based archiving, management, and retrieval of preclincial molecular imaging data are described. RESULTS: Initial performance tests of the Molecular Imaging Data Grid system have been conducted at the USC IPILab using dedicated VMware servers. System connectivity, evaluated datasets, and preliminary results are presented. The results show the system's feasibility, limitations, direction of future research. CONCLUSIONS: Translational and interdisciplinary research in medicine is increasingly interested in cellular and molecular biology activity at the preclinical levels, utilizing molecular imaging methods on animal models. The task of integrated archiving, management, and distribution of these preclinical molecular imaging datasets at preclinical molecular imaging facilities is challenging due to disparate imaging systems and multiple off-site investigators. A Molecular Imaging Data Grid design, implementation, and initial evaluation is presented to demonstrate the secure and novel data grid solution for sharing preclinical molecular imaging data across the wide-area-network (WAN).

Evolving minimally invasive spine surgery: a surgeon's perspective on technological convergence and digital or control system.

Degenerated spinal disc and spinal stenosis are common problems requiring decompressive spinal surgery. Traditional open spinal discectomy is associated with significant tissue trauma, greater morbidity/complications, scarring, often longer term of convalescence, and even destabilization of the spine. Therefore, the pursuit of less traumatic minimally invasive spine surgery (MISS) began. The trend of spinal surgery is rapidly moving toward MISS. MISS is a technologically dependent surgery, and requires increased utilization of advanced endoscopic surgical instruments, imaging-video technology, and tissue modulation technology for performing spinal surgery in a digital operating room (DOR). It requires seamless connectivity and control to perform the surgical procedures in a precise and orchestrated manner. A new integrated DOR, the technological convergence and control system SurgMatix(R), was created in response to the need and to facilitate MISS with "organized control instead of organized chaos" in the endoscopic OR suite. It facilitates the performance, training, and further development of MISS.

A multimedia electronic patient record (ePR) system for image-assisted minimally invasive spinal surgery.

PURPOSE: This paper presents the concept of bridging the gap between diagnostic images and image-assisted surgical treatment through the development of a one-stop multimedia electronic patient record (ePR) system that manages and distributes the real-time multimodality imaging and informatics data that assists the surgeon during all clinical phases of the operation from planning Intra-Op to post-care follow-up. We present the concept of this multimedia ePR for surgery by first focusing on image-assisted minimally invasive spinal surgery as a clinical application. METHODS: Three clinical phases of minimally invasive spinal surgery workflow in Pre-Op, Intra-Op, and Post-Op are discussed. The ePR architecture was developed based on the three-phased workflow, which includes the Pre-Op, Intra-Op, and Post-Op modules and four components comprising of the input integration unit, fault-tolerant gateway server, fault-tolerant ePR server, and the visualization and display. A prototype was built and deployed to a minimally invasive spinal surgery clinical site with user training and support for daily use. SUMMARY: A step-by-step approach was introduced to develop a multimedia ePR system for imaging-assisted minimally invasive spinal surgery that includes images, clinical forms, waveforms, and textual data for planning the surgery, two real-time imaging techniques (digital fluoroscopic, DF) and endoscope video images (Endo), and more than half a dozen live vital signs of the patient during surgery. Clinical implementation experiences and challenges were also discussed.

Image-assisted knowledge discovery and decision support in radiation therapy planning.

The need for quantified knowledge and decision-support tools to handle complex radiation therapy (RT) imaging and informatics data is becoming steadily apparent. Lessons can be learned from current CAD applications in radiology. This paper proposes a methodology to develop this quantified knowledge and decision-support tools to facilitate RT treatment planning. The methodology is applied to cancer patient cases treated by intensity modulated radiation therapy (IMRT). The use of the "inverse treatment planning" and imaging intensive nature of IMRT allows for the development of such image-assisted tools for supporting decision-making thus providing better workflow efficiency and more precise dose predictions.

Experiences with a prototype tracking and verification system implemented within an imaging center.

RATIONALE AND OBJECTIVES: Most health care facilities currently struggle with protecting medical data privacy, misidentification of patients, and long patient waiting times. This article demonstrates a novel system for a clinical environment using wireless tracking and facial biometric technologies to automatically monitor and identify staff and patients to address these problems. MATERIALS AND METHODS: The design of the location tracking and verification system (LTVS) was based on a workflow study which was performed to observe the physical location and movement of patient and staff at the Healthcare Consultation Center II (HCC II) running hospital information systems, radiology information systems, picture archive and communication systems, and a voice recognition system. Based on the results from this workflow study, the LTVS was designed using a wireless real-time location system and a facial biometric system integrated with the radiology information system. The LTVS was tested for its functionality in a laboratory environment, then evaluated at HCC II. RESULTS: Experimental results in the laboratory and clinical environments demonstrated that patient and staff real-time location information and identity verification can be obtained from LTVS. Warning messages can immediately be sent to alert staff when patient's waiting time is over a predefined limit, and unauthorized access to a security area can be audited. Additionally, patient misidentification can be prevented during the course of examinations. CONCLUSIONS: The system enabled health care providers to streamline the patient workflow, protect against erroneous examinations and create a security zone to prevent, and audit unauthorized access to patient health care data required by the Health Insurance Portability and Accountability Act mandate.

Predicting clinical image delivery time by monitoring PACS queue behavior.

The expectation of rapid image retrieval from PACS users contributes to increased information technology (IT) infrastructure investments to increase performance as well as continuing demands upon PACS administrators to respond to "slow" system performance. The ability to provide predicted delivery times to a PACS user may curb user expectations for "fastest" response especially during peak hours. This, in turn, could result in a PACS infrastructure tailored to more realistic performance demands. A PACS with a stand-alone architecture under peak load typically holds study requests in a queue until the DICOM C-Move command can take place. We investigate the contents of a stand-alone architecture PACS RetrieveSend queue and identified parameters and behaviors that enable a more accurate prediction of delivery time. A prediction algorithm for studies delayed in a stand-alone PACS queue can be extendible to other potential bottlenecks such as long-term storage archives. Implications of a queue monitor in other PACS architectures are also discussed.

Wireless remote control of clinical image workflow: using a PDA for off-site distribution and disaster recovery.

This paper describes a picture archiving and communication system (PACS) tool based on Web technology that remotely manages medical images between a PACS archive and remote destinations. Successfully implemented in a clinical environment and also demonstrated for the past 3 years at the conferences of various organizations, including the Radiological Society of North America, this tool provides a very practical and simple way to manage a PACS, including off-site image distribution and disaster recovery. The application is robust and flexible and can be used on a standard PC workstation or a Tablet PC, but more important, it can be used with a personal digital assistant (PDA). With a PDA, the Web application becomes a powerful wireless and mobile image management tool. The application's quick and easy-to-use features allow users to perform Digital Imaging and Communications in Medicine (DICOM) queries and retrievals with a single interface, without having to worry about the underlying configuration of DICOM nodes. In addition, this frees up dedicated PACS workstations to perform their specialized roles within the PACS workflow. This tool has been used at Saint John's Health Center in Santa Monica, California, for 2 years. The average number of queries per month is 2,021, with 816 C-MOVE retrieve requests. Clinical staff members can use PDAs to manage image workflow and PACS examination distribution conveniently for off-site consultations by referring physicians and radiologists and for disaster recovery. This solution also improves radiologists' effectiveness and efficiency in health care delivery both within radiology departments and for off-site clinical coverage.