Conjunctival goblet cells (CGCs) are specialized epithelial cells secreting mucins to form the mucus layer of the tear film. The mucus layer spreads the tear film on the ocular surface for protection. The dysfunction and death of CGCs cause tear film instability and are associated with various ocular surface diseases, including dry eye disease (DED). CGC examination is essential for the precise diagnosis and effective treatment of ocular surface diseases. A research team has developed a high-performance depth of field microscopy system for non-invasive CGC examination in patients.
The high-speed extended depth of field (DOF) microscopy technique has a 1 mm DOF (25x DOF extension) and ten frames per second imaging speed. A deformable mirror was used in the system to sweep the imaging plane axially and to capture CGCs on the arbitrary tilted conjunctiva in single frames.
The acquired images contained both in-focus and out-of-focus information. The researchers used deconvolution to filter the in-focus information only.