Computerized Quantitation of Gastric Ulcers
We have developed a computer method for quantitation of gastric lesions. The technique of direct scanning of stomach samples sandwiched in a transparent plastic folder has been introduced for simple, rapid, cost-effective and efficient morphological evaluation of gastric lesions .
The conventional photography-based methods for quantitation of gastric lesions tend to be highly subjective, error-prone, and tedious. This study reports a simple and novel method for visualization of experimental gastric lesions by direct scanning of stomach samples and their quantitation by using computer-assisted image analysis. Gastric mucosal lesions were produced by indomethacin or ethanol in rats. The stomachs were removed, opened along the greater curvature, and washed. The flattened stomach samples were sandwiched within a transparent plastic folder and scanned. The captured image was saved and subjected to lesion quantitation using a freely accessible image analysis program, Scion Image. A macro subroutine was optimized for automation of the entire procedure for ease in frequent applications. The images obtained by direct scanning of stomach samples showed excellent morphologic visualization of gastric lesions. The standard spots having variable areas of same density, or same areas of variable densities, showed a direct relation with signal intensity (pixels). A linear correlation was observed between measured and actual values of the known standard areas.
Figure. Scanned images of indomethacin-induced (top left) and ethanol-induced (top right) gastric lesions in rats. Middle panel shows the same images after optimized background subtraction (125 for indomethacin- and 150 for ethanol-induced lesions). The line graphs (lower panel) show the profiles of gastric lesions along the planar axis.
The representative samples of indomethacin- and ethanol-induced gastric ulcers showed the total lesion areas of 4.62+/-0.74 and 169.26+/-13.23 mm2, respectively. Direct scanning of stomach samples is a simple, cost-effective, rapid, and efficient procedure for morphologic evaluation of experimental gastric lesions. The output images of scanned stomach samples are superior to scanned photographs, and can be instantly used for quantitative assessment of mucosal injury using the image analysis program.
Khan HA. Computer-assisted visualization and quantitation of experimental gastric lesions in rats. J Pharmacol Toxicol Method 2004; 49: 89-95.