Always measure both eyes and repeat if the difference between eyes is greater than 0.3 mm, or if consecutive measurements differ by more than 0.2 mm.

When should you repeat biometry?

Purpose : It is standard practice to repeat biometry every 1-2 years prior to cataract surgery.

What is the most common error made in immersion biometry?

The most common cause is an axial length error (0.1 mm error = 0.25-0.3 D surprise). A myopic surprise occurs if the AL measurement is too short, and a hyperopic surprise occurs if the measurement is too long. Therefore, accurate biometry is essential.