Stephen M. Moore

The Cancer Imaging Archive (TCIA): Maintaining and Operating a Public Information Repository

The National Institutes of Health have placed significant emphasis on sharing of research data to support secondary research. Investigators have been encouraged to publish their clinical and imaging data as part of fulfilling their grant obligations. Realizing it was not sufficient to merely ask investigators to publish their collection of imaging and clinical data, the National Cancer Institute (NCI) created the open source National Biomedical Image Archive software package as a mechanism for centralized hosting of cancer related imaging. NCI has contracted with Washington University in Saint Louis to create The Cancer Imaging Archive (TCIA)—an open-source, open-access information resource to support research, development, and educational initiatives utilizing advanced medical imaging of cancer. In its first year of operation, TCIA accumulated 23 collections (3.3 million images). Operating and maintaining a high-availability image archive is a complex challenge involving varied archive-specific resources and driven by the needs of both image submitters and image consumers. Quality archives of any type (traditional library, PubMed, refereed journals) require management and customer service. This paper describes the management tasks and user support model for TCIA.

IHE: a model for driving adoption of standards.

The development of communication standards in healthcare is a major ongoing engineering effort. While there is little doubt that this effort has made possible significant advances in the performance of healthcare information and imaging systems, overall levels of systems interoperability have not improved as dramatically as one might reasonably expect and the cost of implementing effectively integrated systems remains high. The lag between the development of information standards and their implementation in real systems and institutions is a genuine problem in healthcare. This paper describes an ongoing initiative that attempts to bring together healthcare professionals and industry experts to coordinate the implementation of standards in ways that enhance operational efficiency and the quality of patient care.

DICOM shareware: a public implementation of the DICOM standard

This software was designed to satisfy the requirements of the 1993 DICOM demonstration and is not intended to provide a complete system. However, this software does provide an example implementation which can be used to gain understanding about the DICOM Standard and has successfully communicated with the 20 vendors who participated in the DICOM demonstration at the 1993 RSNA. This software is written in ANSI-C and has been compiled under the following operating systems: SunOS, Solaris, Ultrix, OSF/1, Irix, NextSTEP. This poster describes the implementation of the software, how the software can be used, and how the software can be obtained.

An Evaluation of the Use of Sieves for Producing Estimates. Of Radioactivity Distributions with the EM Algorithm for PET

Reconstructions of spatial-distributions of radioactivity produced using maximum-likelihood estimation in positron-emission tomography exhibit noise-like artifacts in the form of sharp peaks and valleys located randomly throughout the image field. These become increasingly apparent with each stage of iteration when the expectation-maximization algorithm is used to produce the maximum-likelihood estimate numerically. In this paper, we present a preliminary evaluation of the use of Grenanders method of sieves to reduce these undesirable artifacts.

TCIA: An information resource to enable open science

Reusable, publicly available data is a pillar of open science. The Cancer Imaging Archive (TCIA) is an open image archive service supporting cancer research. TCIA collects, de-identifies, curates and manages rich collections of oncology image data. Image data sets have been contributed by 28 institutions and additional image collections are underway. Since June of 2011, more than 2,000 users have registered to search and access data from this freely available resource. TCIA encourages and supports cancer-related open science communities by hosting and managing the image archive, providing project wiki space and searchable metadata repositories. The success of TCIA is measured by the number of active research projects it enables (>40) and the number of scientific publications and presentations that are produced using data from TCIA collections (39).

Collecting 48,000 CT exams for the lung screening study of the National Lung Screening Trial.

From 2002–2004, the Lung Screening Study (LSS) of the National Lung Screening Trial (NLST) enrolled 34,614 participants, aged 55–74 years, at increased risk for lung cancer due to heavy cigarette smoking. Participants, randomized to standard chest X-ray (CXR) or computed tomography (CT) arms at ten screening centers, received up to three imaging screens for lung cancer at annual intervals. Participant medical histories and radiologist-interpreted screening results were transmitted to the LSS coordinating center, while all images were retained at local screening centers. From 2005–2007, all CT exams were uniformly de-identified and delivered to a central repository, the CT Image Library (CTIL), on external hard drives (94%) or CD/DVD (5.9%), or over a secure Internet connection (0.1%). Of 48,723 CT screens performed, only 176 (0.3%) were unavailable (lost, corrupted, compressed) while 48,547 (99.7%) were delivered to the CTIL. Described here is the experience organizing, implementing, and adapting the clinical-trial workflow surrounding the image retrieval, de-identification, delivery, and archiving of available LSS–NLST CT exams for the CTIL, together with the quality assurance procedures associated with those collection tasks. This collection of CT exams, obtained in a specific, well-defined participant population under a common protocol at evenly spaced intervals, and its attending demographic and clinical information, are now available to lung-disease investigators and developers of computer-aided-diagnosis algorithms. The approach to large scale, multi-center trial CT image collection detailed here may serve as a useful model, while the experience reported should be valuable in the planning and execution of future equivalent endeavors.

Considerations in moving electronic radiography into routine use

Primary diagnosis plays a central role in the establishment of electronic radiography as a trusted technology. From this technology, other applications in radiology and medicine can easily flow. The fidelity of the electronic presentation of images, the ability of the radiologist to transfer film-based reading skills to a digitally based presentation, and the achievement of improvements in diagnostic efficiency are three important steps to building confidence in electronic methods in radiology. A discussion of these issues is presented as a prelude to the description of a plan for the use of broadband technology and multimedia in electronic radiography, both within and between hospitals. >

Breast milk cellular HIV-specific interferon γ responses are associated with protection from peripartum HIV transmission.

Objective:Breast milk is a major route of infant HIV infection, yet the majority of breast-fed, HIV-exposed infants escape infection by unknown mechanisms. This study aimed to investigate the role of HIV-specific breast milk cells in preventing infant HIV infection. Design:A prospective study was designed to measure associations between maternal breast milk HIV-specific interferon-&ggr; (IFN-&ggr;) responses and infant HIV-1 detection at 1 month of age. Methods:In a Kenyan cohort of HIV-infected mothers, blood and breast milk HIV-gag IFN-&ggr; ELISpot responses were measured. Logistic regression was used to measure associations between breast milk IFN-&ggr; responses and infant HIV infection at 1 month of age. Results:IFN-&ggr; responses were detected in breast milk from 117 of 170 (69%) women. IFN-&ggr; responses were associated with breast milk viral load, levels of macrophage inflammatory protein (MIP) 1&agr;, MIP-1&bgr;, regulated upon activation, normal T-cell expressed, and secreted and stromal-cell derived factor 1 and subclinical mastitis. Univariate factors associated with infant HIV infection at 1 month postpartum included both detection and breadth of breast milk IFN-&ggr; response (P = 0.08, P = 0.04, respectively), breast milk MIP-1&bgr; detection (P = 0.05), and plasma (P = 0.004) and breast milk (P = 0.004) viral load. In multivariate analyses adjusting for breast milk viral load and MIP-1&bgr;, breast milk IFN-&ggr; responses were associated with an approximately 70% reduction in infant HIV infection [adjusted odds ratio (aOR) 0.29, 95% confidence interval (CI) 0.092–0.91], and each additional peptide pool targeted was associated with an approximately 35% reduction in infant HIV (aOR 0.65, 95% CI 0.44–0.97). Conclusion:These data show breast milk HIV-gag-specific IFN-&ggr; cellular immune responses are prevalent and may contribute to protection from early HIV transmission. More broadly, these data suggest breast milk cellular responses are potentially influential in decreasing mother-to-child transmission of viruses.

Creation of a CT Image Library for the Lung Screening Study of the National Lung Screening Trial

The CT Image Library (CTIL) of the Lung Screening Study (LSS) network of the National Lung Screening Trial (NLST) consists of up to three annual screens using CT imaging from each of 17,308 participants with a significant history of smoking but no evidence of cancer at trial enrollment (Fall 2002–Spring 2004). Screens performed at numerous medical centers associated with 10 LSS-NLST screening centers are deidentified of protected health information and delivered to the CTIL via DVD, external hard disk, or Internet/Virtual Private Network transmission. The collection will be completed in late 2006. The CTIL is of potential interest to clinical researchers and software developers of nodule detection algorithms. Its attractiveness lies in its very specific, well-defined patient population, scanned via a common CT protocol, and in its collection of evenly spaced serial screens. In this work, we describe the technical details of the CTIL collection process from screening center retrieval through library storage.

Image Quality Assurance in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Network of the National Lung Screening Trial

The National Lung Screening Trial is evaluating the effectiveness of low-dose spiral CT and conventional chest X-ray as screening tests for persons who are at high risk for developing lung cancer. This multicenter trial requires quality assurance (QA) for the image quality and technical parameters of the scans. The electronic system described here helps manage the QA process. The system includes a workstation at each screening center that de-identifies the data, a DICOM storage service at the QA Coordinating Center, and Web-based systems for presenting images and QA evaluation forms to the QA radiologists. Quality assurance data are collated and analyzed by an independent statistical organization. We describe the design and implementation of this electronic QA system, emphasizing issues relating to data security and privacy, the various obstacles encountered in the installation of a common system at different participating screening centers, and the functional success of the system deployed.