Image processing and automated cell analysis.

Illustration of the individual steps from image acquisition to cell analysis performed for each muscle section. A, B) Single fluorescent microscopic images were merged to obtain a full-scale image of the entire muscle section at an appropriate magnification to see individual muscle fiber outlines. C) The contrast of the overall images was enhanced by edge detection. D, E) A commercial histogram based segmentation algorithm automatically performed measurements of cross sectional area (CSA) and minimal Feret’s diameter for each detected object. Objects not fulfilling certain criteria (area >250 μm2, perimeter < 430 μm, roundness < 2) were considered artefacts and excluded from further analysis. F) shows distributions of Minimum Feret’s diameter from a typical control and a stimulated muscle.