Pathology screening, in more ways than one
Two heads often are better than one, it is said. However, the old adage does not go far enough, at least when it comes to group diagnostic situations, where pathologists, radiologists and surgeons at a hospital review a case before deciding on a course of treatment. During such collaborations, two, four, six or more heads will be involved, along with twice as many eyes.
The challenge comes in presenting the complete diagnostic picture to all those viewers, noted Tedd Kelemen, clinical product manager for Olympus Canada Inc. “The pathologists are going to get their crack at it. They’re going to present data in one way, shape or form. It’s generally going to be visual data.”
Imagery of a cell is captured and displayed via an Olympus microscopy imaging system that uses a Toshiba HD camera and display.
This presentation has been handled in various ways in the past, but a new approach now is possible, thanks to technical advances. Olympus has incorporated a high-definition camera and display from Toshiba into a microscope imaging system. The system enables a group of clinicians to view a pathology slide on the screen almost as though the slide were being seen in a microscope by each group member individually.
Although pathologists often capture data using a digital camera, in the past their first option in presenting that data was a report. They would embed their images in a document and deliver the report to the tumor review board. Unfortunately, this took time and also required the pathologists to anticipate questions. If someone wanted to look at part of a slide at a magnification that differed from the one in the report, he was out of luck.
Toshiba uses a proprietary prism block technology to divide incoming light and route it to red, green and blue CCD imagers to ensure that each color is captured at full resolution.
Pathologists had another option. They could set up a microscope in the review room, hook up a video camera and feed the 30-fps images to a display. However, generally such cameras were analog, and they captured images according to the NTSC standard. As a result, the resolution and the contrast were often limited.
Connecting such a camera to a new high-definition display did not help and sometimes led to problems because the aspect ratio of new displays is 16:9, whereas the camera would be outputting 4:3 aspect ratio images. This difference could change the shape of images on the screen, a potential problem because cell shape is important in pathology.
As a final option, pathologists could elect to use a multiheaded microscope. Olympus itself makes such systems, which can have as many as 18 heads. This solution requires plenty of space, special tables and technical support, but it does have the advantage of being accepted for primary diagnosis.
Sufficient detail, contrast and color are important when viewing a slide, but these are not the only key parameters in a group diagnostic session. “Speed is very important. They need to be able to see the whole slide at all the magnifications the microscope has,” Kelemen said.
After evaluating various solutions, Olympus developed a microscopy imaging system based on a high-definition camera with a display from Toshiba. The 30-fps camera outputs data in a 1080i format. It has three CCD sensors with a prism block that ensures the right optical alignment of the sensors to one another. Because of the nature of the audience, the alignment has an offset of a half pixel of the green to the red and blue.
“The human eye sees more green, so when we do that half-pixel offset, that makes it the best possible image quality you can get to the human eye,” said Gary Pitre, Eastern regional sales manager of the Imaging Systems Div. of Toshiba America Information Systems in Irvine, Calif.
The 42-in. LCD display that presents the data has a maximum resolution of 1920 × 1080 pixels, a contrast ratio of 1000:1, brightness of 600 candelas per square meter and a viewing angle of nearly 180¼.
The product has just been released and now is undergoing initial evaluations by tumor review boards and other parties. So far, these efforts have generated a very positive response. “Everybody agrees it’s the best live visualization tool they’ve ever seen. They have no issues about being able to diagnose from what they’re seeing on the display,” Kelemen said.
In addition to clinical settings, the system could be used in a teaching environment, allowing students and instructors to see the same specimen. One possible future enhancement would be the addition of the ability to snap a picture, but Kelemen noted that this would have to be done in a simple manner so as not to interfere with the system’s primary intended use, which is visualization.
Contact: Gary Pitre, Toshiba America Information Systems Inc., Irvine, Calif.; e-mail: firstname.lastname@example.org; Tedd Kele-men, Olympus Canada Inc., Markham, Ontario, Canada; e-mail: email@example.com.
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