Diagnoses Rendered by Whole Slide Imaging (WSI) Alone Are Accurate for Use in a General Surgical Pathology Practice
Walter S Campbell, Subodh M Lele, William W West, Lynette M Smith, Steven H Hinrichs. University of Nebraska Medical Center, Omaha, NE; University of Nebraska Medical Center, College of Public Health, Omaha, NE
Background: Whole Slide Imaging (WSI) holds promise for supporting many of the functional requirements of a general surgical pathology service. Multiple recent studies have described applications for pathology education and training, distant consultation and general diagnostic use. Several validation studies have been conducted to date. However, their data sets have either been limited or highly focused on single organ/tissue types and have not established equivalence between WSI and light microscopy (LM) for general diagnostic purposes. The purpose of this study was to determine the diagnostic concordance between pathologic interpretations using WSI and LM in routine surgical pathology practice with a broad array of tissue types and cases.
Design: 215 consecutive previously signed out surgical pathology cases were included in the study. A broad array of case types and tissue sources was represented. All slides from each case were scanned (digitized at 20x) and presented to two senior pathologists (who had not seen any of the cases previously in any format) for diagnosis using WSI as the sole diagnostic tool. Diagnoses rendered by WSI were compared to the original LM diagnoses (recorded in archival surgical pathology reports) and concordance determined by a third senior pathologist.
Results: Concordance between WSI and LM was 98% and concordance between the two WSI pathologists was 99%. Five (5) cases were determined to have discordant diagnoses, two of which were clinically significant, between those recorded using WSI and archived LM diagnoses. Discordant cases resulted from interpretive criteria or diagnostic error whereas the WSI modality did not contribute to these diagnostic differences. Problems encountered by the pathologists were primarily related to the inability to clearly visualize microscopic details at higher power due to poor digital magnification of the 20x slide scans and difficulty in digital image navigation. Advantages of WSI noted include the ability to visualize a very low power image (lower than that provided by LM), ease of measurement using the built in scale and the comfort of viewing slides from any place.
Conclusions: This study supports the use of WSI in general surgical pathology. Improvements in image navigational ability and clarity in visualization of microscopic detail at higher power would help in further advancing the adaptability of this method to a general surgical pathology practice.
Category: Quality Assurance
Monday, March 19, 2012 1:00 PM
Poster Session II # 284, Monday Afternoon