Final answer:
The Maddox rod is used to detect strabismus, not amblyopia, astigmatism, or presbyopia. To diagnose astigmatism, a special chart is used to detect uneven focus in the eye, whereas the Maddox rod assesses eye alignment.
Step-by-step explanation:
The Maddox rod is a tool used in eye examinations to detect the presence of strabismus, which is an alignment disorder where the orientation of one eye differs from the other. It is not used to diagnose amblyopia (lazy eye), astigmatism (a condition where the cornea is irregularly shaped causing blurred vision), or presbyopia (age-related difficulty in focusing on close objects, often noticeable around the age of 40-45). To diagnose astigmatism, a special chart such as the one shown in Figure 26.8, which has multiple lines radiating from a center point, is used to detect uneven focus in the eye. If, when looking at the center cross of this chart without glasses, some lines appear darker or clearer than others, this indicates the presence of astigmatism.