Patients who have myopia in the left eye and a normal right eye, i.e., refractive parametrization, may be due to congenital developmental abnormalities, poor eye habits, and other causes. The refractive state of one eye of the patient is completely normal, while the other eye, in the case of abnormal development, may form myopia due to the excessive length of the eye axis or excessive refractive power of the cornea and lens. In addition to this, the condition may also be triggered if the patient has bad eye habits, such as always using one eye to see or shading one eye. When the difference in myopia between the two eyes is less than 300 diopters, the patient can still be corrected by wearing ordinary frames. Once the difference in myopia exceeds 300 diopters, patients may experience discomfort such as double vision when wearing frames, and can improve their vision through corneal contact lenses or laser surgery. It is recommended that patients with refractive error should consult a doctor in a timely manner to assess their condition and follow the doctor’s instructions for treatment.