Improvised polarising light microscopy using low-cost linear polarised film sheets: An experience in a low-resource pathology laboratory setting in Nigeria

Abstract

ABSTRACT Background: Polarizing microscopy is widely used in pathology to demonstrate the deposition of endogenous materials, the presence of anisotropic exogenous in tissue samples and to evaluate materials that demonstrate optical birefringence. Polarizing microscopes are costly and can cost up to several thousands in dollars; a cheaper alternative includes using a regular light microscope with polarizer kits but this may also be out of reach in low-resourced pathology practice. Aims/Objectives The aim is to share our experience with the use of improvised polarizing film to demonstrate birefringence in tissue samples. Materials and Methods: Two films measuring 6x7cm were cut out from generic linear polarizing films procured from an online store. The cutout films were placed on each other and crossed such that their polarizing planes were at a right angle. While maintaining this polarizing plane, one of the films was placed over the light source (polarizer) and the other over the slide (analyzer). The light microscope was adjusted for desirable intensity and contrast. Results: Tissue sections of suture granuloma, gout, and medullary thyroid carcinoma were used for demonstrating birefringent suture material, brightly anisotropic urate crystals, and birefringent amyloid deposits respectively. Conclusion: We present a practical and cost-effective solution for performing polarizing microscopy in low-resource pathology laboratory settings using linear polarizing films.