Affiliations: Address for correspondence: Peter Gombas, MD Division
of Pathology, MI Central Hospital, Varosligeti fasor 9-11, H-1071 Budapest,
Hungary Telephone : **36-3-227-620 FAX : **36-3-220-892 E-mail :
peter.gombas@bm.gov.hu
Abstract: AIMS: Although various telepathology techniques have recently been
developed globally to enable telecommunication in pathology, pathologists seem
to have reservations about implementing cyber age tools in professional
practice. Static telepathology (ST) is easy and inexpensive but most of the
methods used have been biased due to the low explicit/implicit ratio of
transferred information. Our object was to develop a method of ST, which make
the technique less biased. METHODS: Digital images of cytological and
histopathological samples were captured with a bright field transmitted light
microscope. Static images were stored on a hard disk and transferred to various
remote locations via a local network, connected to the Internet. To determine
the degree of bias of ST method, ratio of explicit/implicit information /REI/
has been calculated. RESULTS: The degree of bias of transferred digital images
strongly depends on both the size of the image and numerical aperture of the
objective lenses used to capture the image. Using images with a resolution of
800 x 800 pixels REI of small biopsies was approximately 1:1 when they were
captured with an objective lens at a magnification of X10. However, REI of a
section with an area typical of that used for pathological diagnosis (approx.
1x1 cm) captured at the same magnification proved to be only 0.01. We found
that increasing the magnification of the objective lens used to capture the
image, the REI decreased significantly. Although it is possible to increase the
resolution of digital images by capturing them with high-resolution cameras or
by the use of a slide scanner, this is not always helpful. We recommend, that
hierarchic arrangements of digital images captured in the "x, y" and "z" planes
and presented in the form of an image pyramid may ameliorate some of the
difficulties associated with static digital image transfer. CONCLUSION: Storage
and transfer of digital images enable complex information exchange using
Internet protocols. ST methods are inexpensive and broadly accessible. The use
of the image pyramid system can reduce the degree of bias significantly. It
seems to be a useful method for expert discussions, consultations, archiving
and education.
Keywords: telepathology, telemedicine, internet, image pyramid, image storage and retrieval