Grid server allows instant sharing of medical images globally

A grid computing system is providing the infrastructure for radiologists, pediatric oncologists, and other physicians at 40 hospitals across North America to quickly and securely exchange high-resolution images, providing the framework for rendering specialists' second opinions and determining whether children who have cancer are responding to therapy.

"We have broken the medical image communication barrier," said Stephan Erberich, director of Functional Imaging and Biomedical Informatics at Childrens Hospital Los Angeles.

Erberich, a computer scientist, described at the RSNA meeting the Globus Medicus system, an open-source grid collaboration software project developed at Viterbi School of Engineering's Information Sciences Institute (ISI) and Argonne National Laboratories (ANL).

Carl Kesselman and Ann Chevernak of ISI, who worked with Erberich in creating Medicus, based the system on DICOM and its potential for transparent data exchange among collaborating researchers and physicians.

According to Erberich, access to patient data has been limited to the hospital where the images were acquired and not available even to the patient's point-of-care facility, if different, unless physically carried there.

"Today if you leave the hospital, you either leave your digitized images behind or you have to carry them on a CD-ROM," Erberich said. "This is not the 21st century healthcare we need in a networked society."

But, using the DICOM Grid Interface Service (DGIS) and Medicus, DICOM records at medical facilities anywhere are now easily accessible and exchangeable, he said.

The MEDICUS project began when Erberich approached Kesselman and Chervenak and asked them "to translate DICOM into grid," Erberich said.

Kesselman had, as part of the Globus project, previously helped more than a dozen scientific communities - from high-energy physicists to geologists simulating earthquakes - share instruments and data.

"There had to be new code developed to handle the medical-specific things like DICOM translation and patient confidentiality assurance," Kesselman said, "but this leverages all of the existing underlying Globus technology that we use in many other projects."

Erberich developed the DICOM-to-grid interface and led the interdisciplinary collaboration among the engineering and clinical teams, working with Childrens Hospital radiologist in chief and chairman Dr. Marvin D. Nelson.

The system has been in place since September.

"(It's) totally transparent," Nelson said. "Each facility is now connected to the grid using its own interface. You only need one interface and that serves the whole hospital by reusing the hospital's capital investment in DICOM visualization devices."

The cost of installing a DGIS node is trivial, said Erberich, about $1000 for a grid gateway attached to a high-bandwidth net connection. The gateway provides two-way access to the grid, allowing images to be uploaded after they are stripped of patient identification. It also provides access to a catalog of archived DICOM records.

"If researchers have authorization for a specific record in the catalog, it can be downloaded for use on their own image display," Nelson said

One dramatic change in practice will be the ease of review. Researchers can look at observations made anywhere on the grid without leaving their offices.

"We store the images here in the data center," Erberich said, "but the people who have been assigned to review images can review them from virtually anywhere. Before, when we were documenting a research study, it meant that radiologists would have to physically come to a single facility and look through a file cabinet full of physical images. Now, radiologists all over the planet can look at the images in their own offices, on their own favorite commercial medical imaging system."