Whether or not to add astigmatism when fitting glasses for highly nearsighted patients has a bearing on whether or not the patient has astigmatism themselves. If astigmatism is present, astigmatism should be added. High myopia is defined as myopia of more than 600 degrees, which is a type of refractive error, while astigmatism is also a refractive error, and the two can be combined. If a patient with high myopia has astigmatism, the number of astigmatism should be added to the glasses, which can improve the corrected visual acuity and visual quality. If a patient with high myopia does not have astigmatism, the number of astigmatism does not need to be added to the glasses. The patient needs to go to the ophthalmology department of the hospital to determine whether there is astigmatism through the optometry examination, and then the doctor can review it through the use of a comprehensive optometry instrument, and finally issue a prescription for glasses.