HDR-Microscopy of Cell Specimens: Imaging and Image Analysis

Bright field microscopy is applied in both biomedical research and diagnostics. The cellular material is generally imaged with cameras mounted onto the microscope, allowing thus to measure cell properties. However, these cameras exhibit only a limited dynamic range, which makes the quantification of these properties difficult or even impossible. We therefore show how the dynamic range can be increased by acquiring a set of differently exposed images of a specimen. These high dynamic range (HDR) images allow to measure features, which are otherwise difficult to capture, if at all. We show that HDR-microscopy not only increases the dynamic range, but furthermore reduces noise and improves the measurements of colors. We develop HDR microscopy-based algorithms for three different applications essential for early cancer diagnostics, viz, detection of positive cells in immunocytochemical marker stained material, nuclei segmentation in low contrast morphologically stained material, and detection of certain subcellular features, so- called AgNORs, in silver (Ag) stained specimens.