It's possible that you are seeing an eye worm, which can be common in tropical areas. I would seek a vet if possible, in case it is scar tissue, or something else. Oxyspirura Mansoni isthe name of the eye worm in chickens, and it can be treated off-label with Valbazen 1/2 ml given orally, Valbazen and water in equal parts applied into the eye, and then repeat both of these with 10-14 days. Other products recommended online are 5% cresol solution (the active ingredient in Lysol, which should be immediately rinsed out of the eye afterward) and levamisole, another type of dewormer. A vet may also remove it directly from the eye under anesthesia. There is not a lot of information about dealing with this problem, and although products such as VetRX claim to treat it, I am doubtful that it works. Here is some reading about eye worm:
http://parasitipedia.net/index.php?option=com_content&view=article&id=2654&Itemid=2943
From THE MERCK VETERINARY MANUAL:
Eggs of
Oxyspirura mansoni, Manson eyeworm, are deposited in the eye, reach the pharynx via the nasolacrimal duct, are swallowed, passed in the feces, and ingested by the Surinam cockroach,
Pycnoscelus surinamensis. Larvae reach the infective stage in the cockroach. When infected intermediate hosts are eaten, liberated larvae migrate up the esophagus to the mouth and then through the nasolacrimal duct to the eye, where the cycle is completed. Other insect species may also serve as the intermediate host.
Oxyspirura mansoni is a slender nematode, 12–18 mm long, found beneath the nictitating membrane of chickens and other fowl in tropical and subtropical regions. The parasite causes various degrees of inflammation, lacrimation, corneal opacity, and disturbed vision.
As a treatment for Manson eyeworm, a local anesthetic can be applied to the eye, and the worms in the lacrimal sac exposed by lifting the nictitating membrane. A 5% cresol solution (1–2 drops) placed in the lacrimal sac kills the worms immediately. The eye should be irrigated with sterile water immediately to wash out the debris and excess solution. The eyes improve within 48–72 hr and gradually become clear if the destructive process caused by the parasite is not too far advanced.
