Astigmatism – Causes, Symptoms & Types

For starters, Astigmatism is probably the most misunderstood vision problem. This is not an eye disease but a refractive error, meaning it’s simply a problem with how the eye focuses light. In an eye with astigmatism, light fails to come to a single focus on the retina to produce clear vision. Instead, multiple focus points occur, either in front of the retina or behind it or sometimes both.

Causes of Astigmatism:

Astigmatism usually is caused by an irregularly shaped cornea. Instead of the cornea having a symmetrically round shape (like a baseball), it is shaped more like a football, with one meridian being significantly more curved than the meridian perpendicular to it. In some cases, astigmatism is caused by the shape of the lens inside the eye. This is called lenticular astigmatism, to differentiate it from the more common corneal astigmatism.

Symptoms of Astigmatism:

Astigmatism usually causes vision to be blurred or distorted to some degree at all distances. Symptoms of astigmatism include eye strain and headaches, especially after reading or other prolonged visual tasks. Squinting also is a very common symptom.

Types of Astigmatism:

There are three primary types of astigmatism:
•    Myopic astigmatism: One or both principal meridians of the eye are nearsighted.
•    Hyperopic astigmatism: One or both principal meridians are farsighted.
•    Mixed astigmatism: One principal meridian is nearsighted, and the other is farsighted.

Astigmatism can also be classified as regular or irregular. In regular astigmatism, the principal meridians are 90 degrees apart (perpendicular to each other). In irregular astigmatism, the principal meridians are not perpendicular. Most astigmatism is regular corneal astigmatism, which gives the front surface of the eye a football shape.
Irregular astigmatism can result from an eye injury that has caused scarring on the cornea, from certain types of eye surgery or from keratoconus, a disease that causes a gradual thinning of the cornea.

Like most disorders concerning the eyes, this one also needs to be corrected as early as possible, delaying which can even lead to permanent blindness. Ayurveda has corrective therapies that can heal astigmatism and leading Ayurvedic Hospitals in Kerala conduct regular clinics to detect and correct this disorder.