If the eye was caught in a burn or scratched by tree branch or finger nail then it is very likely that it will heal nicely with minimal eye damage.
However, 10-20% of injuries could result in corneal scarring, which if central can affect eye sight and the visual acuity will be deteriorated in addition to various ocular distortions; but if peripheral to the cornea i.e. dose not involve the line of vision then the vision might be less affected.
This usually happens from the distortion of the corneal shape centrally secondary to the scarring that is affecting the periphery of the cornea. Contact lens wearers are at risk to develop contact lens related corneal infection that is uncommon but potentially devastating complication of contact lens wear.
The infection comes primarily from the bacteria present on the lids and in the tears. It is estimated that one in 2,500 daily contact lens wearers and 1 in 500 overnight wearers develop bacterial keratitis each year(the overall risk of any complication in contact lens wearers is 1/20 per year).
Treatment: Early treatment of the causative agent is crucial to minimize consequences such as residual corneal scarring. In the acute phase of eye trauma or infection, topical antibiotics, eye lubricants, and later steroids eye drops are used. Any remaining scar on the cornea could be treated if symptomatic (affecting vision or causing a lot of discomfort). Usually treatment is delayed for 6 months after initial injury to allow the body to heal itself. In our experience, many corneal scars fade out with time and vision improves gradually.
If no improvement then surgical intervention becomes indicated and this varies from laser surgery, which is simple and effective in the very superficial scars, to partial thickness corneal transplant which can be superficial in case of superficial scar in the cornea (Superficial lamellar keratoplasty) to deep lamellar keratoplasty (DALK) for deeper corneal scars. We use femtosecond laser to assist corneal transplantation. In some cases two types of lasers are used to give the best possible visual outcomes.