How to read an eyeglass prescription from a hospital

Under normal circumstances, an optometry prescription from a hospital should be interpreted by examining indicators such as eye designation, spherical power, cylindrical power, astigmatism axis, and pupillary distance. The specific details are as follows:

1. Eye designation: "R" typically represents the right eye, and "L" represents the left eye. Identifying the correct eye is essential before interpreting the subsequent data.

2. Spherical power (SPH): This indicates the degree of myopia or hyperopia and is denoted by "S". The normal range is from 0 to +50 degrees. A "+" sign usually indicates hyperopia (farsightedness), while a "-" sign indicates myopia (nearsightedness).

3. Cylindrical power (CYL): This refers to the degree of astigmatism and is represented by "C". The normal range is within 50 degrees.

4. Astigmatism axis: This indicates the direction of astigmatism and appears only when astigmatism is present. The axis ranges from 0 to 180 degrees and is denoted by "A". Common normal values are 180, 90, and 45 degrees.

5. Pupillary distance (PD): This is the distance between the centers of the pupils, indicated by "PD". The average pupillary distance is approximately 61 mm for males and 58 mm for females.

If myopia or hyperopia is present, it is recommended to seek timely medical treatment to prevent potential adverse effects.