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Summary: An astigmatism is a condition in which the cornea of the eye is not spherical, but instead more like the shape of a football. Discover how astigmatisms can be caused by an altered curvature on the cornea, or in the lens with help from an optometrist in this free video on optical astigmatisms.
Dr. Raj Patel is an optometrist at Vancouver Vision Center in Vancouver, Wash.read more
"Hi, I'm Doctor Raj Patel at Vancouver Vision Clinic here in Vancouver, Washington. And I'm here to talk to you a little bit about what is optical astigmatism. And so you may have heard as astigmatism being described as a condition where the front of the eye in the cornea here resembles the shape of a football more so than the shape of a basketball. And so when that occurs the cornea is not completely round or spherical. So as a result when light passes through there and focuses on the back of the eye it's out of focus and that in general is a simplistic view of astigmatism, when the surface of the eye isn't completely spherical isn't completely smooth and round like a basketball. And so astigmatism can happen in one or two places. We can get that altered curvature on the cornea right here or we can also get it on the inside the in the structure called the lens. So when it happens inside the eye on the lens, it's the same concept which is that the lens isn't completely round and instead is a little football shaped. So either if the lens is a little football shaped or the cornea is a little bit football shaped or oblong, we call that either corneal astigmatism or lenticular astigmatism. And so in fact it's really rare to find somebody that has completely round eyes, completely spherical corneas or spherical lenses. And it's a really rate individual. Most individuals actually have some small amount of astigmatism on the cornea or on the lens. And so when you have that condition, when the light passes through the eye, it makes two focal points instead of one. And as a result we have to correct that using a variety of lenses or contact lenses or even surgically you can correct astigmatism. Astigmatism might slowly worsen over time and it occasionally runs in families and so if somebody in the family has a large amount of astigmatism it's most likely the case that others will as well. So that's kind of an overview of how astigmatism works, and until we meet again next time."
eHow Article: What Is an Optical Astigmatism?
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