Contact lens assisted imaging with integrated flexible handheld probe for glaucoma diagnosis

• Main Authors: Hong, Jeesmond Xun Jie, Shinoj, Vengalathunadakal Kuttinarayanan, Murukeshan, Vadakke Matham, Baskaran, Mani, Aung, Tin
• Other Authors: Asundi, Anand K.
• Format: Conference or Workshop Item
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Mechanical engineering; Glaucoma; Iridocorneal Angle Imaging
• Online Access: https://hdl.handle.net/10356/81570; http://hdl.handle.net/10220/47494
• Institution: Nanyang Technological University

Angle closure glaucoma accounts for majority of the bilateral blindness in Asian countries such as Singapore, China, and India. Abnormalities in the optic nerve and aqueous outflow system are the most indicative clinical hallmarks for glaucoma of this clinical subtype. Traditional photographic imaging techniques to assess the drainage angle are contact based, and may expose patients to risk of corneal abrasion and infections. In addition, these procedures require the use of viscous ophthalmic gels as coupling medium to overcome the phenomenon of total internal reflection at the tear-air interface. In this paper, we propose an integrated flexible handheld probe consisting of a micro color CCD video camera and white light LEDs. The handheld probe is able to capture images of the fundus and opposite iridocorneal angle when placed at the central cornea or limbus respectively. Here, we propose the use of hydrogel contact lens as an index matching medium and better protective barrier, as an alternative to conventional ophthalmic gels. The proposed imaging system and methodology has been successfully tested on porcine eye samples, ex vivo. With its high repeatability, reproducibility, and a good safety profile, it is believed that the proposed imaging system and methodology will complement existing imaging modalities in the diagnosis and management of glaucoma.