LAUSR

Hanna and Pantanowitz have presented a very wellwritten and informative summary to answer the above question. I have several comments. It is a given that image acquisition from cytopathology glass slides represents a greater challenge because of the distribution of material on multiple focal planes between the glass slide and coverslip. It may be difficult to focus into cell collections on resulting whole-slide imaging (WSI). z-stacking is an option, but can never perfectly match the infinite vertical focus provided by a traditional microscope and glass slide. In addition, the more z-stacks on WSI, the greater the file size and often the more cumbersome the viewing. However, there usually are thousands of cells on a cytology slide; it is unusual to make a diagnosis from just 1 or 2 small foci on the slide. So it may be that we need to reexamine digital cytopathology with a fresh pair of “lenses.” A different approach may be required, such as acquiring 2 separate WSI files scanned at different focal depths from the one original glass slide. Alternatively, one may crop and extract adequately scanned areas prior to diagnosis; after all, even with traditional cytopathology, there always is cellular material left behind in the preservative fluid or on the sampling utensil, which the pathologist never actually views. Others have found that digitizing less than the entire glass specimen did not compromise accuracy. Using 2-dimensional WSI to facilitate learning or the diagnosis of cytopathology cases has been found to be comparable to traditional microscopy. Cytopathology WSI with multiple focal planes may even be superior to the equivalent glass slides for diagnostic accuracy. The issue is more our perception. It is almost universally perceived that diagnostic accuracy using WSI does not match the accuracy achieved with a glass slide and a traditional microscope. It takes longer to report WSI compared with a glass slide. However, there also is a definite learning curve when using WSI: increased diagnostic accuracy and increased time efficacy come with increased WSI use and familiarity. Ergonomics for screening cytopathology slides also can be readily addressed. Becoming accustomed to an altered approach may simply be the answer. We need to try it, familiarize ourselves with it, and then validate it (case-by-case to start with). Then, if the technique is not inferior in accuracy and safety for our patients compared with traditional techniques, perhaps we should go with it.