In our study, we evaluated the technical feasibility and diagnostic concordance of a digital histological section evaluation system and compared it with the routine OM procedure.
Low cost computational techniques were used. The scanning speed was too slow for routine applications, but there are free resources available for increasing scanning speed by several magnitudes. The digitisation card should be changed to a higher resolution and speed (×10). The computer should also be updated (×5). In addition, an automated microscope could be considered.
Image quality should be further enhanced using a digital one chip, analogue three chip camera instead of the analogue, one chip camera used at present. In this case, an increase in diagnostic accuracy would be expected.
However, these developments and results show that in the near future we can have microscope free virtual microscopy workstations with the functions of the optical microscope. One advantage would be a more comfortable working environment for histologists. In addition, it would also support quality control techniques and consultation with remote experts. The first application of digital slides and virtual microscopy should be telepathology consultation. However, later this technology could be used in the routine histology evaluation process, as was done in our study.
Remote evaluation of the slides through the Internet has the advantages of the previously used static or dynamic telepathology methods (the entire slide is available at high magnification, microscope and remote assistance free evaluation).25
We found a higher concordance with optical microscopy than previous static image based telepathology studies.13–15
This might be explained by the fact that this technology eliminates sampling error.
Time constraints and fatigue were not evaluated. We are planning to assess these factors in a larger interlaboratory study.
“In the near future we can have microscope free virtual microscopy workstations with the functions of the optical microscope”
The reasons for discordance yielded new information for future developments. In selected cases several focus planes are required for correct diagnosis. The virtual microscope cannot be used for the analysis of underlying cells. However, with further technical and mathematical developments several focus levels can be recorded, stored, and evaluated by the virtual microscope.
In his 1996 review article, O’Brien stated that the computerisation of the histology laboratory was desirable but that it would be far in the future.26
More, recently, Leong and McGee27
stated that complete automated slide digitisation has influence at all levels of clinical practice and education. They emphasised the importance of dedicated software technology. Recently, the usefulness of digital slides and virtual microscopy for quality assurance and teaching applications has been demonstrated.28,29
Our results show that digital slides and virtual microscopy technology can be used in selected cases for telepathology consultation. After the definition of the time and storage requirements the routine use of this technique could also be considered.
Take home messages
- We found diagnostic concordance between optical microscopy and virtual microscopy on gastrointestinal biopsy specimens
- Virtual microscopy has the advantage of providing a more comfortable working environment for histologists
- Virtual microscopy also supports quality control techniques and consultation with remote experts
- Initially, digital slides and virtual microscopy should be used in telepathology consultation
- After further evaluation of time and storage constraints this technology might be useful in routine histology