A pre exam can include:

  • NCT (Non-Contact Tonometer): This device uses a gentle puff of air to measure the pressure inside the eye. This is usually done as a glaucoma screening test.
  • Pachymetry: The pachymeter uses ultrasound to measure the thickness of the cornea (clear tissue in front of the colored iris). This measurement enables greater accuracy when measuring the pressure inside the eye. Corneal thickness measurements are also used to help determine if a patient is a candidate for laser vision correction.
  • Auto-Refractor: This instrument estimates the patients prescription. This can be used by the doctor as a starting point in the eye exam.