Digital images produced in the pathology laboratory today are most commonly used for education, consultation and quality assurance purposes. This will soon change as newer technologies - for both acquiring and managing the images - are welcomed into pathology. Clinicians forecast that the adoption of digital imaging will not only improve diagnosis and patient care, but facilitate the integration of images in pathology reports and electronic medical records as well as advance telepathology.
Digital imaging in anatomic pathology and the clinical lab is becoming more widespread as community hospitals, academic medical centers and industrial laboratories move to incorporate the technology into their pathology practice. The benefits include instant online access to images, telepathology and the integration of images into pathology reports and electronic medical records (EMRs). The new systems also reduce costs and improve the efficiency of departmental workflow.
But there have been and remain a few bridges to cross on the road to digital conversion. Before pathology information system (PIS) vendors began offering add-on imaging modules, many digital imaging efforts in pathology grew out of customized solutions. Additionally, pathology cases are not digital from their inception. Scanning entire microscopic slides - similar to digitizing x-rays in radiology - is not a mature technology. Pathologists today produce images of gross specimens and microscopic slides using a digital camera. The images are loaded onto a PC, stored on a hard drive and usually discarded after a certain period of time.
But once a healthcare organization decides to utilize digital imaging in pathology, it's a whole different ballgame. A number of issues and questions must be addressed from the start:
- How will this change workflow?
- At a departmental level, how much storage will be devoted to the system?
- Will the digital image of the slide become a permanent part of the patient's record?
- How much integration will be involved between pathology and other departments?
ACQUIRING THE IMAGE
When a digital image is captured in pathology using a camera on a microscope, it is saved temporarily as a data file. The static image is usually JPEG compressed and on average between 150 and 250 kilobytes. Static images can be transferred within a department to specialists and consultants for secondary review. With the appropriate equipment and credentialing, the images also can be sent via the internet to a remote viewing station for consultation for telepathology.
Capturing a digital image can be a rather laborious process. "It is up to the pathologist to choose the field that represents the pathologic findings," says Walter Henricks, MD, director of laboratory information services at the Cleveland Clinic and president of the Association for Pathology Informatics (API). "Someone has to take the time to select the field and capture the image. That's not part of routine microscopic work right now. Typical workflow includes looking at the slide, dictating the report and moving on to the next case. To get that into a digital image, I need to find the field that represents what I want to show, select the correct focus, select the correct magnification and select the correct picture and do something with that picture."
Virtual microscopy - a new technology - automatically converts entire glass slides into a series of digital images. Whole slide images are in the range of megabytes and gigabytes, says Michael Becich, MD, PhD, professor of pathology at the UPMC Health System-Shadyside, part of the University of Pittsburgh Medical System, and founder of InterScope Technologies, Wexford, Pa., a provider of high-speed automated digital imaging systems.
The goal of virtual microscopy is to scan every slide and present the pathologist the image on a computer monitor rather than have him or her manipulate glass slides. While the slide is still produced in the regular laboratory, it gets loaded onto an imaging robot (such as InterScope's new Xcellascan Slide Scanning Station that can automatically load 500 slides at a time). Using an optical light source and a robotic device that scans the anatomic pathology slide, a digital image is produced (at roughly five minutes per one square centimeter of material on a slide). That time will be reduced to under a minute, Becich says, which will facilitate virtual microscopy's ability to handle the clinical workload of a pathology department.