Pseudobuphthalmos is a relatively well-known ailment that has been reported in captive geckos worldwide, including several New Zealand species.
Geckos have eyes that are structurally different from many lizards i.e., geckos do not have complete eyelids, and instead have a transparent scale (spectacle) covering the eye. The spectacle forms a seal over the eye, creating a sub-spectacular space between the spectacle and the eyeball. Within this space is a tear-like secretion produced by the Harderian gland, which allows for free movement of the eye under the spectacle. When functioning correctly, nasolacrimal ducts (tear ducts) drain the excess fluid into the mouth. However, pseudobuphthalmos (meaning ‘false enlargement of the eyeball’) occurs due to blockage of the tear-duct, resulting in accumulation of this fluid behind the spectacle and ‘bulging’ of the eye.
In captivity, the condition can often present as a secondary symptom to stomatitis (inflammation of the mouth) or alimentary tract infections. In particularly bad cases, geckos may experience loss of vision in the affected eye due to the spectacle becoming opaque.
The condition may resolve itself, or require surgical draining of the sub-spectacular space by a veterinarian, and can re-occur regardless.