CPO FREE CPO Tonometry Principles and Procedures Questions and Answers 3

Question 1

Which of the following tonometry methods is specifically designed to be LEAST affected by corneal biomechanical properties such as thickness and rigidity?

Accepted Answer

Dynamic contour tonometry (DCT)

Answer

Goldmann applanation tonometry (GAT)

Answer

Non-contact (air-puff) tonometry (NCT)

Answer

Schiotz indentation tonometry

Question 2

A patient with significant nystagmus requires an IOP check. Which of the following tonometers would be most challenging to use and likely yield an inaccurate measurement for this specific patient?

Accepted Answer

Goldmann applanation tonometer

Answer

Tono-Pen

Answer

Pneumatonometer

Answer

Rebound tonometer

Question 3

When performing a calibration check on a Goldmann tonometer, the feeler arm is tested at positions 0, 2, and 6 on the measurement drum. What does the '2' setting correspond to in mmHg?

Accepted Answer

20 mmHg

Answer

2 mmHg

Answer

10 mmHg

Answer

It corresponds to the second hash mark, not a specific pressure.

Question 4

A paraoptometric is preparing to measure IOP on a patient who had myopic LASIK surgery two years ago. Compared to the patient's true IOP, a Goldmann applanation tonometer (GAT) reading is most likely to be:

Accepted Answer

Artificially low due to the altered corneal thickness and biomechanics.

Answer

Artificially elevated due to increased corneal rigidity.

Answer

Accurate, as the cornea has stabilized post-surgery.

Answer

Variable and unpredictable, requiring multiple measurements.

Question 5

A patient presents with advanced keratoconus. When using a Goldmann tonometer, the paraoptometric notes that obtaining a clear mire endpoint is difficult due to the irregular corneal shape. The resulting IOP measurement is likely to be:

Accepted Answer

An underestimation of the true IOP.

Answer

Significantly overestimated.

Answer

Highly accurate despite the difficulty.

Answer

Accurate only if taken on the peripheral cornea.

Question 6

During a calibration check of a Goldmann tonometer at the '2' setting (20 mmHg), the technician turns the dial to 2.05. According to standard procedure, how should the feeler arm respond if the tonometer is accurate?

Accepted Answer

It should fall toward the patient.

Answer

It should remain perfectly still.

Answer

It should fall toward the examiner.

Answer

It should oscillate between the patient and examiner.