How do you calibrate an applanation tonometer?

How do you calibrate an applanation tonometer?

Calibration at dial position 0

1. At dial position 0, the feeler arm should be in free movement. If the dial is turned backwards a small distance (to the equivalent of position −0.05), the arm should fall towards the examiner.
2. If the arm does not respond in the above way, the tonometer is inaccurate at dial position 0.

How often does a Goldmann tonometer need to be calibrated?

The authors recommend that GATs ≤1 year old be checked for calibration errors every 6 months, and GATs >1 year old be checked monthly.

How do you clean Applanation tonometer?

The Goldmann applanation prism tip can be wiped with gauze soaked in 70% isopropyl alcohol and then dried before use. Gonioscopes should be cleaned in running water, wiped with gauze soaked in 70% isopropyl alcohol, and then dried before use.

How do you calibrate a Goldmann tonometer?

1. Start on the ‘0’ mark. Turn the dial 0.5 mmHg downwards/anti-clockwise.
2. Now turn the dial 0.5mmHg forwards/clockwise. The tonometer probe should rock forwards, towards the patient.
3. Adjust the calibration rod to the ’20’ mark and repeat the above process either side of the mark.
4. Repeat again for the ’60’ mark.

What are the types of tonometer?

Types of tonometry

• Goldmann and Perkins applanation tonometry. The Goldmann applanation tonometer measures the force necessary to flatten a corneal area of 3.06mm diameter.
• Non-Contact Tonometry. Air Puff Tonometer.
• Schiotz Tonometer.
• Pneumotonometer.
• Tono-Pen.

How does Applanation tonometry work?

This test measures fluid pressure in your eye. The test involves using a slit lamp equipped with forehead and chin supports and a tiny, flat-tipped cone that gently comes into contact with your cornea. The test measures the amount of force needed to temporarily flatten a part of your cornea.

What is indentation tonometry?

The principle of indentation tonometry is that a force or a weight will indent or sink into a soft eye further than into a hard eye.

When should the tip of the Applanation tonometer be disinfected?

In view of the potential for transmission of viruses (e.g., herpes simplex virus [HSV], adenovirus 8, or HIV) 184 by tonometer tips, CDC recommended that the tonometer tips be wiped clean and disinfected for 5-10 minutes with either 3% hydrogen peroxide, 5000 ppm chlorine, 70% ethyl alcohol, or 70% isopropyl alcohol 95 …