AESTHESIOMETERY USES IN OPHTHALMIC PRACTICE
This is a procedure by which we check the corneal sensitivity. Sensitivity of cornea is decreased markedly in viral corneal ulcers, neuroparalytic keratitis.
It is decreased to some extent in all types of affections of cornea. So testing of corneal sensitivity is very important for diagnosis of corneal diseases.
It is done by two methods:
1. Make the patient sit on a stool comfortably. Ask him to keep looking straight with wide open eyes.
Take sterile cotton and make it into a wick with very fine tip. Bring the cotton wick from behind the patient and touch the cornea at various points.
Note down the blinking. Compare it with other eye using a different wick. Normally when cornea is touched with a cotton wick; patient blinks.
However if corneal sensitivity is decreased then blinking is also decreased proportionately.
This is the most common method employed clinically to test the sensitivity of cornea.
2. An aesthesiometer is an instrument with a fine nylon tip. Instead of cotton wick this is used to test the corneal sensitivity.
Different amount of pressure can be used to touch the cornea and notice blink reflex.
Accordingly more is the pressure required to elicit blink reflex, lesser is the sensitivity of cornea.