Why is trichiasis dangerous?
With trichiasis, the eyelashes grow inward and constantly scratch the cornea. The patient feels a speck in the eye, the eye waters and turns red, and erosions form on the cornea, which can turn into an ulcer and leave cloudiness. The doctor removes abnormally growing eyelashes with tweezers under slit lamp control after drip anesthesia. The procedure provides quick relief, but the eyelash grows back in 4–8 weeks, so for persistent trichiasis, radical methods are considered - destruction of the hair follicle or eyelid surgery.
Why is the drug injected into the eye?
The eye is separated from the general bloodstream by a blood-ophthalmic barrier: the medicine taken in tablets reaches the retina in a negligible concentration. Therefore, local administration is widely used in ophthalmology - drops, injections under the conjunctiva, parabulbar, retrobulbar and directly into the vitreous body.
The deeper the drug is injected, the higher the concentration in the desired area, but the stricter the requirements for sterility and technique.
Types of drug administration
- subconjunctival - under the mucous membrane of the eye
- parabulbar - in the tissue around the eyeball
- retrobulbar - behind the eyeball, closer to the optic nerve
- intravitreal - directly into the vitreous body
What is important for the patient to know
Injections are performed after instillation of anesthetic drops, so pain is minimal. A slight hemorrhage under the conjunctiva after an injection is a common and safe occurrence; it resolves in 1–2 weeks. You should consult a doctor if pain increases, vision decreases, and redness increases a day after the procedure.