Biometry

Question 1

Which of the following statements BEST describe the process used to check the accuracy of the Goldmann applanation tonometer?

A. It should be calibrated daily for reliable results
B. It can be performed in the office with a calibrating rod
C. It can only be handled at the factory or instrument repair shop
D. It is accomplished with a test sphere with a standard tension of 30 mm HG

Answer 1

B. It can be performed in the office with a calibrating rod

Question 2

What is the MOST commonly used technique to perform a B-scan?

A. Slit lamp
B. Handheld probe
C. Computed topography (CT)
D. Magnetic Resonance Imaging (MRI)

Answer 2

B. Handheld probe

Question 3

In A-scan biometry, which ocular measurement provides the axial length of the globe?

A. Anterior corneal surface to anterior vitreous face
B. The distance between corneal surface and the retinal surface
C. Pre-corneal tear film to the posterior pole
D. Pre-corneal tear film to the posterior face

Answer 3

B. The distance between corneal surface and the retinal surface

Question 4

What A-scan measurement is MOST important in determining intraocular lens (IOL) power?

A. Corneal curvature
B. Anterior chamber depth
C. Lens thickness
D. Axial length

Answer 4

D. Axial length

Question 5

How are ultrasound biometric measurements obtained?

A. The anterior lens spike should be lower than posterior lens spike
B. The patient must have good vision
C. The probe should be aligned along the visual axis of the eye
D. The biometrist must press firmly on the globe

Answer 5

C. The probe should be aligned along the visual axis of the eye

Question 6

Axial length is provided by which measurement?

A. Pre-corneal tear film to the posterior vitreous face
B. Anterior corneal surface to the macula
C. Anterior corneal surface to the optic disc
D. Anterior pole to the posterior pole

Answer 6

B. Anterior corneal surface to the macula