Use of Crossed Polarizers to Enhance Images of the Eyelids

Abstract

Purpose To describe imaging the external eye with crossed polarizers to enhance clinically important features in digital photographs of the eyelids. Methods External photographs with and without crossed polarizing filters were taken of patients with blepharitis and controls with no clinical eye pathology. Results Photographing eyelid skin through crossed polarizers decreased reflections on the skin surface and improved visualization of eyelid telangiectasias and blood vessels in patients with a broad range of skin pigmentation and ethnicities. Conclusions The use of crossed polarizers in imaging the external eye reduces reflections and glare from the eyelid skin and margins, thereby allowing for a more detailed evaluation of underlying structures and analysis of images. These findings suggest that including crossed polarizers in clinical photography has informative applications for assessing eyelid disease.

Standardized clinical photography considerations in patients across skin tones

“…Cross‐polarized photos can be obtained using a circular polarizer on the DSLR camera lens and a linear polarizer on the flash oriented downwards at 45°, as previously reported by O’Sullivan et al 4 . Use of smartphones for mobile and inexpensive cross‐polarized capture has also been reported 5 .…”

“…Cross‐polarized light photography is performed using two polarizers placed perpendicularly, one on the lens and another on the light source, eliminating specular reflections from the skin. Whereas nonpolarized (white) light enhances superficial skin texture and structures, cross‐polarized light allows back‐scattered light from deeper levels of the skin to reach the eye or camera, thereby enhancing visualization of subsurface structures including underlying blood vessels and chromophores 2,4 . Cross‐polarized light enables more objective characterization of skin colour and has been utilized to assess colour changes in various conditions including inflammatory dermatoses, ecchymosis and acne 2,4 …”

“…2,4 Cross-polarized light enables more objective characterization of skin colour and has been utilized to assess colour changes in various conditions including inflammatory dermatoses, ecchymosis and acne. 2,4 In dermatology, cross-polarization is the primary technique behind polarized dermoscopy to visualize deeper dermal structures and birefringent structures such as collagen (white streaks). 2 Outside of dermatology, its applications span diverse fields including dentistry, forensics and astronomy.…”

“… 2 , 4 Cross‐polarized light enables more objective characterization of skin colour and has been utilized to assess colour changes in various conditions including inflammatory dermatoses, ecchymosis and acne. 2 , 4 …”

“…Cross‐polarized photos can be obtained using a circular polarizer on the DSLR camera lens and a linear polarizer on the flash oriented downwards at 45°, as previously reported by O’Sullivan et al . 4 Use of smartphones for mobile and inexpensive cross‐polarized capture has also been reported. 5 When available, authors recommend use of cross‐polarized photos to complement standard clinical photography when documenting erythematous lesions in patients with SOC.…”