Digital cytopathology: A constant evolution (Comments on Capitanio et al. Digital cytology: A short review of technical and methodological approaches and applications)

Abstract

Capitanio et al provide a succinct review of digital cytopathology technology with particularly good overviews of scanner focusing methodologies as well as explanations of deep focusing techniques. The aim of this letter to the editor is to briefly comment and expand on some of the information provided by these authors.

Whole Slide Imaging Technology and Its Applications: Current and Emerging Perspectives

“…On the other hand, air-dried Romanowsky-stained smears can be scanned with only x and y-axes, as air drying flattens the cells thus minimizing the requirement of z-stacking. 91,92 Given the ongoing need for a cytologic diagnosis, the trend of using WSI in cytopathology may possibly increase in the future as minimally invasive procedures to obtain material for genetic/molecular analysis are used. The possibility to scan whole slides and to organize them in structured databases accessible via the internet would represent a powerful educational resource.…”

“…90 Certain problems encountered while using WSI in cytology smears compared to the histology sections include (a) presence of dense overlapping tissue fragments making it difficult for scanners to focus on the cells; (b) red cell contamination of the smear and/or background acellular material(s) leading the scanner to focus on red cells and/or the background material rather than the cells of interest; (c) smears with scant cellularity making z-stacking difficult; and (d) need to remove the screening marks/dots before scanning (for which keeping a photographic record of the diagnostic screening marks is recommended). 91 Papanicolaou- and H&E-stained smears often have cells in multiple planes due to wet fixation, and thus require z-scanning to obtain a crisp, high quality image. On the other hand, air-dried Romanowsky-stained smears can be scanned with only x and y -axes, as air drying flattens the cells thus minimizing the requirement of z-stacking.…”

“…On the other hand, air-dried Romanowsky-stained smears can be scanned with only x and y -axes, as air drying flattens the cells thus minimizing the requirement of z-stacking. 91,92…”