Accuracy and Perception of an Origami-Based Paper Microscope When Compared to the Conventional Light Microscope in Oral Cytology.

Introduction: Foldscope is an origami-based portable paper microscope, developed in 2014, that can provide up to 2000 times magnification. It has the potential use as a low-cost diagnostic alternative in areas with limited resources. Oral cancer screening camps rely on visual examination of the patients' oral cavity. In-field diagnosis of cytological smears can be very beneficial, although it requires more resources. Therefore, we designed a study to compare the accuracy of Foldscope in the identification of features in cytology smears, when compared with light microscope. Methodology: Two examiners with adequate experience evaluated 35 oral cytology smears. The Foldscope was used twice for evaluation by each examiner, with a gap of 15 days between the two evaluations. Both examiners also evaluated the same set of slides using a light microscope. Accuracy of identification of cells using Foldscope, when compared with the light microscope was evaluated. Interobserver agreement in the identification of various features was also determined using kappa statistics, for light microscope examination, and two Foldscope examinations. Results: We found that both examiners could identify epithelial cells accurately using the Foldscope. Mucous cells, inflammatory cells, and microorganisms could also be identified, with slightly lesser accuracy. Interobserver agreement was good in the light microscope. However, with the Foldscope, especially after the second sitting, the interobserver agreement was found to be comparably good. Conclusion: With adequate training and practice, Foldscopes could be valuable tools for rapid and immediate diagnosis of exfoliative cytology smears in mass oral cancer screening camps.