Question

pring 26 astructor Procedure 6 Testing for Astigmatism The condition called astigmatism is characterized by the faces the corn er These relaties decrease visual acuity because these serres a to focus de precio retina. You can test for astonism by w achache the sho r e 15.12. When you have med procedure, anwer Check Your Understand question p. 417 1 Hold Figure 15.12 a comfortable reading distance from your eyes, about 15 cm (14 inches 2 Cover one eye, and stare at the center of Fire 1 All lines are distinct and back. If any of the lines appear blurry or gra, astigmatism may be present 3 Cover the other eye and repeat the process 4 as asthmatisment in the eye? The par theca nucle ferio 15 AGURE 15.12 Astigmatism test chart. 402 Exploring Anatomy & Physiology in the Laboratory

Answer 1

Astigmatism is a very common visual acuity. In this problem, the shape of the cornea is irregular. Due to the irregularity of the cornea, it could not focus at a single point on the retina which causes blurry images.

The given image could be used to test astigmatism. In case, a person is having normal vision, all lines in the image will appear distinct and black. But in case, the person is having astigmatism, lines may seem blurry or indistinct or multiple lines. The procedure of this test should be done with each eye with an alternate eye closed while looking at the image. This will give an idea of whether both eyes are normal and free from astigmatism. In case, one eye is having astigmatism, the appearance of indistinct lines swill be there seeing with that eye.