Nice study in this month's Clinical Transplantation on light versus virtual microscopy.
Increasingly studies are showing equal or superior interobserver agreement with virtual over light microscopy.
What if we find whole slides are better than glass slides in terms of diagnostic accuracy compared with "truth" or "gold standard" diagnosis?
Clin Transplant. 2011 Sep 29. doi: 10.1111/j.1399-0012.2011.01506.x. [Epub ahead of print]
Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada Department of Pathology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey Alberta Transplant Applied Genomics Centre Department of Medicine, Division of Nephrology and Transplant Immunology, University of Alberta, Edmonton, AB, Canada.
Virtual microscopy has begun to change conventional pathology practice. We tested the reliability of this new technology in transplantation pathology. We studied 40 kidney transplant biopsies for cause and compared reproducibility of Banff scores using virtual slides versus glass slides. Three glass slides per biopsy were scanned as high-resolution digital slides using Aperio ScanScope. Three pathologists independently reviewed the biopsies: twice by glass slides and twice by virtual slides. Eleven histopathological lesions were scored and used to construct diagnosis according to Banff criteria. The intra-observer reproducibility of Banff scores was substantially good using either virtual slides or glass slides (mean κ: 0.69 vs. 0.64, p > 0.05). The inter-observer reproducibility of Banff scores was better in virtual slides than in glass slides (mean κ: 0.42 vs. 0.28, p < 0.001). Among the lesions, transplant glomerulopathy scoring by virtual slides showed the highest inter-observer reproducibility, with a similar accuracy to glass slides. The agreement for acute rejection between virtual and glass slides was not different from the agreement between two readings of glass slides. Thus, virtual microscopy is a reliable and more reproducible technology and has several advantages over glass slides, e.g., accessibility via internet, no fading. We recommend virtual microscopy for transplant diagnostics, including utilization for clinical trials.