Certified Ophthalmic Assistant Practice Exam

What is checked during the calibration of an application tonometer?

1. Using a measured weight attached to the tonometer balancing arm

2. Using a reference standard measurement

3. Determining the diameter of the indentation

4. Measuring the intraocular pressure

The correct answer is: Using a measured weight attached to the tonometer balancing arm

During the calibration of an applanation tonometer, the process involves ensuring that the device accurately measures intraocular pressure based on a known set of parameters. Utilizing a measured weight attached to the tonometer balancing arm is a critical step in this calibration process. The weight helps to create a standard indentation on a surface that simulates the corneal surface of the eye. This allows the tonometer to be adjusted to provide precise pressure readings when measuring the actual intraocular pressure (IOP) in a patient. Getting the calibration right ensures that the device will give accurate measurements when it is used clinically, as the tonometer's readings are highly dependent on the correct application of force, which can directly affect the indentation made during the measurement. If the tonometer is not calibrated with a proper weight, it could result in inaccurate readings, potentially leading to misdiagnosis or inappropriate treatment plans for patients. The other options touch on the importance of measurements in the context of tonometry but are not directly related to the specific calibration process of an applanation tonometer. Reference standards may be significant in a broader context of ensuring precision but do not represent the immediate calibration process. Determining the diameter of the indentation and measuring intraocular pressure are outcomes of the tonometry procedure rather