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Background: Acquiring well-focused digital images of cytology slides with scanners can be challenging due to the 3-dimensional nature of the slides. This study evaluates performances of whole-slide images (WSIs) obtained from 2 different cytopreparations by 2 distinct scanners with 3 focus modes. Methods: Fourteen urine specimens were collected from patients with urothelial carcinoma. Each specimen was equally divided into 2 portions, prepared with Cytospin and ThinPrep methods and scanned for WSIs using Leica (Aperio AT2) and Hamamatsu (NanoZoomer S360) scanners, respectively. The scan settings included 3 focus modes (default, semi-auto, and manual) for single-layer scanning, along with a manual focus mode for 21 Z-layers scanning. Performance metrics were evaluated including scanning success rate, artificial intelligence (AI) algorithm-inferred atypical cell numbers and coverage rate (atypical cell numbers in single or multiple Z-layers divided by the total atypical cell numbers in 21 Z-layers), scanning time, and image file size. Results: The default mode had scanning success rates of 85.7% or 92.9%, depending on the scanner used. The semi-auto mode increased success to 92.9% or 100%, and manual even further to 100%. However, these changes did not affect the standardized median atypical cell numbers and coverage rates. The selection of scanners, cytopreparations, and Z-stacking influenced standardized median atypical cell numbers and coverage rates, scanning times, and image file sizes. Discussion: Both scanners showed satisfactory scanning. We recommend using semi-auto or manual focus modes to achieve a scanning success rate of up to 100%. Additionally, a minimum of 9-layer Z-stacking at 1 µm intervals is required to cover 80% of atypical cells. These advanced focus methods do not impact the number of atypical cells or their coverage rate. While Z-stacking enhances the AI algorithm's inferred quantity and coverage rates of atypical cells, it simultaneously results in longer scanning times and larger image file sizes.

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Hydrogel-based scaffolds have been widely used to fabricate artificial tissues capable of replacing tissues and organs. However, several challenges inherent in fabricating tissues of large size and complex morphology using such scaffolds while ensuring cell viability remain. To address this problem, we synthesized gelatin methacryloyl (GelMA) based bioink with cells for fabricating a scaffold with superior characteristics. The bioink was grafted onto a Z-stacking bioprinter that maintained the cells at physiological temperature during the printing process, without exerting any physical pressure on the cells. Various parameters, such as the bioink composition and light exposure time, were optimized. The printing accuracy of the scaffolds was evaluated using photorheological studies. The internal morphology of the scaffolds at different time points was analyzed using electron microscopy. The Z-stacked scaffolds were fabricated using high-speed printing, with the conditions optimized to achieve high model reproducibility. Stable adhesion and high proliferation of cells encapsulated within the scaffold were confirmed. We introduced various strategies to improve the accuracy and reproducibility of Z-stack GelMA bioprinting while ensuring that the scaffolds facilitated cell adhesion, encapsulation, and proliferation. Our results demonstrate the potential of the present method for various applications in tissue engineering.

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INTRODUCTION: There is an emerging need for telecytology in Colombia as the demand for cytopathology has increased. However, due to economic and technological constraints telecytology services are limited. Our aim was to evaluate the diagnostic feasibility of using whole slide imaging with and without Z-stacking for telecytology in Colombia, South America. METHODS: Archival glass slides from 17 fine needle aspiration smears were digitized employing whole slide imaging (WSI) (Nanozoomer 2.0 HT, Hamamatsu) in one Z-plane at 40x, and panoramic digital imaging (Panoptiq system, ViewsIQ) combining low-magnification digital maps with embedded 40x Z-stacks of representative regions of interest. Fourteen Colombian pathologists reviewed both sets of digital images. Diagnostic concordance, time to diagnosis, image quality (scale 1-10), usefulness of Z-stacking, and technical difficulties were recorded. RESULTS: Image quality scored by pathologists was on average 8.3 for WSI and 8.7 for panoramic images with Z-stacks (P = .03). However, diagnostic concordance was not impacted by image quality ranking. In the majority of cases (72.4%) pathologists deemed Z-stacking to be diagnostically helpful. Technical issues related to Z-stack video performance constituted only a minor proportion of technical problems reported. Slow downloads and crashing of files while viewing were mostly experienced with larger WSI files. CONCLUSION: This study demonstrated that international telecytology for diagnostic purposes is feasible. Panoramic images had to be acquired manually, but were of suitable diagnostic quality and generated smaller image files associated with fewer technical errors. Z-stacking proved to be useful in the majority of cases and is thus recommended for telecytology.

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OBJECTIVE: The aim of this work was to raise awareness of problems using digital applications for examining, teaching, and applying telecytology at King Abdulaziz Medical City (KAMC), Riyadh, Saudi Arabia; University of Nebraska Medical Center (UNMC), Omaha, NE, USA; and University of Pittsburgh Medical Center (UPMC), Pittsburgh, PA, USA. The objective was to rationalize problems and propose alternative digital approaches. STUDY DESIGN: We sought to identify solutions to improve the following: (a) interpretive examination scores at KAMC for complex cytological templates (i.e., high-grade squamous intraepithelial lesions [HSIL]) when using static digital images (SDI) of cells in regions of interest (ROI); (b) visualization of cells in 3D clusters when teaching at UNMC using 2D and 3D whole-slide imaging (WSI); and (c) visualization of cells through streaming telecytology at UPMC. RESULTS: Composite SDI (CSDI) improved test scores for complex interpretations (i.e., HSIL) by converging diagnostic criteria from multiple ROI. Multiplane focusing through z-stacked WSI facilitated the teaching of cytological entities characterized by 3D cell clusters and consultative telecytology through robotic cell analysis. CONCLUSIONS: Adequately visualized cytomorphology and multiplane focusing are essential for virtual cytopathology examinations, teaching, or consultative telecytology. Visualization of diagnostic criteria through 2D or 3D imaging is critical. Panoptiq panoramic WSI with integrated z-stacked video clips enables optimal applied telecytology.

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