COA - Certified Ophthalmic Assistant Tonometry and Glaucoma Questions and Answers

Question 1

A patient's intraocular pressure (IOP) measures 28 mmHg via Goldmann applanation tonometry.
Pachymetry reveals a central corneal thickness of 610 µm.
How does the corneal thickness likely affect this IOP reading?

Accepted Answer

The true IOP is likely lower than 28 mmHg.

Answer

The true IOP is likely higher than 28 mmHg.

Answer

Corneal thickness does not affect Goldmann tonometry readings.

Answer

The IOP reading is artificially lowered by the thick cornea.

Question 2

Which of the following is considered the 'gold standard' for measuring intraocular pressure?

Accepted Answer

Goldmann applanation tonometry

Answer

Schiotz tonometry

Answer

Non-contact tonometry (NCT)

Answer

Digital palpation

Question 3

A patient presents with a sudden onset of severe eye pain, nausea, blurred vision, and halos around lights. Tonometry reveals a very high IOP. Which type of glaucoma is most likely responsible for these symptoms?

Accepted Answer

Acute angle-closure glaucoma

Answer

Primary open-angle glaucoma

Answer

Normal-tension glaucoma

Answer

Traumatic glaucoma

Question 4

During Goldmann applanation tonometry, the fluorescein mires are observed to be very thick and wide. This is most likely to cause what type of error in the IOP measurement?

Accepted Answer

A falsely high reading

Answer

No error, as mire thickness is irrelevant

Answer

A falsely low reading

Answer

An intermittent reading

Question 5

What is the generally accepted range for normal intraocular pressure (IOP) in the adult population?

Accepted Answer

10-21 mmHg

Answer

5-10 mmHg

Answer

22-30 mmHg

Answer

3-7 mmHg

Question 6

Which of the following is a key principle of applanation tonometry, based on the Imbert-Fick law?

Accepted Answer

Measuring the force required to flatten a specific area of the cornea

Answer

Measuring the depth of indentation on the sclera

Answer

Calculating the rebound speed of a probe from the cornea

Answer

Analyzing the corneal shape change in response to a puff of air

A patient's intraocular pressure (IOP) measures 28 mmHg via Goldmann applanation tonometry.Pachymetry reveals a central corneal thickness of 610 µm.How does the corneal thickness likely affect this IOP reading?

A patient's intraocular pressure (IOP) measures 28 mmHg via Goldmann applanation tonometry.
Pachymetry reveals a central corneal thickness of 610 µm.
How does the corneal thickness likely affect this IOP reading?