Related Experiment Video
Updated: Feb 3, 2026

Preparing Porcine Eyes for Confocal Reflectance Microscopy to Visualize the Vitreous Collagen Fiber Network
Published on: October 17, 2025
Second-harmonic patterned polarization-analyzed reflection confocal microscopy of stromal collagen in benign and
Chukwuemeka Okoro1, Varun Kelkar1, Mayandi Sivaguru2
1University of Illinois at Urbana-Champaign, PROBE Lab, Department of Electrical and Computer Engineering, Urbana, Illinois, 61801, USA.
Abstract:
We present the results of polarimetric analysis of collagen on varying pathologies of breast tissues using second-harmonic patterned polarization-analyzed reflection confocal (SPPARC) microscopy. Experiments are conducted on a breast tissue microarray having benign tissues (BT), malignant invasive lobular carcinoma (ILC), and benign stroma adjacent to the malignant tissues (called the benign adjacent tissue, or BAT). Stroma in BAT and ILC exhibit the largest parameter differences. We observe that stromal collagen readings in ILC show lower depolarization, lower diattenuation and higher linear degree-of-polarization values than stromal collagen in BAT. This suggests that the optical properties of collagen change most in the vicinity of tumors. A similar trend is also exhibited in the non-collagenous extrafibrillar matrix plus cells (EFMC) region. The three highlighted parameters show greatest sensitivity to changes in the polarization response of collagen between pathologies.
Related Concept Videos
Confocal Fluorescence Microscopy
Harmonic Mean
Take the example of the speed of a car, which is the measure of the rate of distance traveled. If the vehicle traverses the same distance back-and-forth, its average speed equals the total distance traveled divided by the total time taken. However, if the car moves with varying speeds, then the arithmetic mean is more skewed...
Total Internal Reflection Fluorescence Microscopy
Group Polarization
Molecular Shape and Polarity
Simple Harmonic Motion

