Differences Between Myopia and Astigmatism
Jun 29, 2022
Source: Cainiu Health
Dr. Chen You
Introduction
The differences between myopia and astigmatism lie in their distinct causes and symptoms. Astigmatism is related to irregular curvature of the cornea, whereas myopia results from light focusing in front of the retina. Symptoms also differ: the hallmark symptom of astigmatism is ghosting (double or blurred images), while myopia is primarily characterized by clear vision of nearby objects but blurry vision of distant objects.
When many people feel their vision is blurry, they often assume it’s simply due to myopia (nearsightedness). In such cases, if you visit an ophthalmology clinic for a vision examination, you may discover that you have some degree of astigmatism. Only by distinguishing between astigmatism and myopia can vision be corrected more effectively. So, what are the differences between myopia and astigmatism?
Differences Between Myopia and Astigmatism
The differences between myopia and astigmatism lie in their underlying causes, symptoms, and stability. Astigmatism arises from irregular curvature of the cornea (or sometimes the lens), whereas myopia results from light focusing in front of the retina rather than directly on it. Their symptoms also differ: the hallmark symptom of astigmatism is “ghosting” (i.e., seeing multiple faint duplicates or halos around objects), while myopia primarily manifests as clear near vision but blurred distance vision. Furthermore, their progression patterns differ. With astigmatism, vision gradually declines, and patients consistently experience overall blurriness—most notably, the “ghosting” phenomenon, wherein a single point appears as multiple points. This is a classic sign of astigmatism. Myopia also leads to decreased visual acuity and blurriness, but unlike astigmatism, it does not cause double or multiple images (“ghosting”). Instead, individuals with myopia can see nearby objects clearly, yet distant objects appear significantly blurred.
Astigmatism requires corrective lenses. Like myopia and hyperopia, astigmatism is a type of refractive error that impairs visual acuity. It occurs when the eye’s optical system fails to focus incoming light precisely onto the retina—typically due to an irregular shape of the cornea or lens at specific meridians. Once diagnosed via refraction testing, astigmatism can be accurately corrected with spectacles prescribed for a specific axis and power, thereby restoring normal visual acuity. Astigmatism tends to induce greater visual fatigue; therefore, wearing corrective lenses and minimizing excessive eye strain helps prevent progressive worsening. For adults with mild astigmatism (≤6 diopters) and stable refractive error, laser vision correction surgery may also be a viable option.
If you notice symptoms suggestive of either condition in daily life, seek timely medical evaluation and follow your doctor’s treatment recommendations. We hope this information has been helpful to you.
