What is the pen top test?
In this test, the optician will ask you to hold your head still while staring at an object such as a pen top.
The optician will then move the object in different directions and observes whether both eyes are able to follow the target freely.
From their knowledge of the position and muscles in the eye the optician is able to determine whether all are working correctly, and if not, which muscle(s) are affected.
You should seek professional advice if you are concerned about your eye health.Book an eye test