Which statement about tonometry is true?

Which statement about tonometry is true?

• A. It measures intraocular pressure
• B. It measures corneal thickness
• C. It measures retinal function
• D. It measures pupil response

Answer: (A)

Tonometry measures intraocular pressure, the pressure inside the eye. This value is essential for glaucoma screening and management because higher IOP can damage the optic nerve over time. Different tonometry methods exist—applanation, non-contact (air puff), and indentation—but they all aim to quantify the pressure, not corneal thickness, retinal function, or pupil response. Be mindful that corneal thickness can affect reading accuracy: thicker corneas may yield higher readings and thinner corneas lower readings, so clinicians may consider pachymetry when interpreting IOP. Retinal function and pupil response are assessed with different tests, such as visual field testing or pupillary reflex exams. Thus, the statement that tonometry measures intraocular pressure is the true one.

Tonometry measures intraocular pressure, the pressure inside the eye. This value is essential for glaucoma screening and management because higher IOP can damage the optic nerve over time. Different tonometry methods exist—applanation, non-contact (air puff), and indentation—but they all aim to quantify the pressure, not corneal thickness, retinal function, or pupil response. Be mindful that corneal thickness can affect reading accuracy: thicker corneas may yield higher readings and thinner corneas lower readings, so clinicians may consider pachymetry when interpreting IOP. Retinal function and pupil response are assessed with different tests, such as visual field testing or pupillary reflex exams. Thus, the statement that tonometry measures intraocular pressure is the true one.