The purpose of the human eyes is to see. Perception or depth, color differentiation, and vision are made able by the cone and rod cells found in the retina part of the organ. Research has indicated that human eyes are capable of seeing ten million different colors. When in need of good eye care, San Antonio is a recommendable location to make a visit. San Antonio eye specialists have the right experience and qualification to handle any disease that affects eyes.
Eyes are not shaped like perfect spheres, rather, they are composed of two pieces fused together. The cornea forms the frontal part. It is transparent in color and appears curved and links to the bigger part referred to as the sclera. The radius of the cornea typically measures 8 millimeters while the sclera measures 12 mm in radius. The limbus ring connects the sclera and cornea. The pupil is surrounded by the iris.
Pupil adjustment is done by two kinds of muscles in the iris called the sphincter muscle and the dilator muscle. The cornea allows external light to pass through. Light coming in through the cornea is converted into electrical signals when it falls on light sensitive cells of the retina. The retina does the conversion of light into electrical signals. Once converted into electrical signals, the optic nerve transports the signals into the brain for processing.
The difference in eye size among adults ranges between one and two millimeters. This fact is consistent among all ethnicities. There is also an observed difference in vertical, horizontal, and sagittal measurements. Differences in these measurements are not gender-based or age-based. From birth to age three, eyes undergo rapid growth and by thirteen years, they attain maximum size.
Eyes are made up of three coats, which enclose three transparent structures. The outermost coat is referred to as the fibrous tunic. The fibrous tunic comprises of the sclera and cornea. The middle layer is called the uvea or vascular tunic. Uvea is comprised of the iris, ciliary body, and choroid. The retina forms the innermost layer. An ophthalmoscope can be used to see all the named layers.
Within the named coats are flexible lens, aqueous humour, and vitreous body. The aqueous humour exists in two places, that is, the anterior chamber the posterior chamber. The location of the anterior chamber is between iris and cornea whereas the posterior chamber is placed between the iris and lens. The lens gets suspended in place by suspensory ligaments. The vitreous body is located behind lens.
The eyes are moved through tension and torque exerted by six different muscles in the organ. The muscles are inferior oblique, medial rectus, lateral rectus, medial rectus, superior oblique, and superior rectus. The globe experiences torque exerted by the muscles and undergoes pure rotation. Less than one millimeter of translation also occurs in the process.
Eyes suffer from a large number of conditions which are caused by different causes such as disease, age, and disorder. Aging causes some changes in eyes, which result in certain medical conditions. Some conditions occur in newborns without external causes. There are many types of eye specialists including opticians, optometrists, and ophthalmologists.
Eyes are not shaped like perfect spheres, rather, they are composed of two pieces fused together. The cornea forms the frontal part. It is transparent in color and appears curved and links to the bigger part referred to as the sclera. The radius of the cornea typically measures 8 millimeters while the sclera measures 12 mm in radius. The limbus ring connects the sclera and cornea. The pupil is surrounded by the iris.
Pupil adjustment is done by two kinds of muscles in the iris called the sphincter muscle and the dilator muscle. The cornea allows external light to pass through. Light coming in through the cornea is converted into electrical signals when it falls on light sensitive cells of the retina. The retina does the conversion of light into electrical signals. Once converted into electrical signals, the optic nerve transports the signals into the brain for processing.
The difference in eye size among adults ranges between one and two millimeters. This fact is consistent among all ethnicities. There is also an observed difference in vertical, horizontal, and sagittal measurements. Differences in these measurements are not gender-based or age-based. From birth to age three, eyes undergo rapid growth and by thirteen years, they attain maximum size.
Eyes are made up of three coats, which enclose three transparent structures. The outermost coat is referred to as the fibrous tunic. The fibrous tunic comprises of the sclera and cornea. The middle layer is called the uvea or vascular tunic. Uvea is comprised of the iris, ciliary body, and choroid. The retina forms the innermost layer. An ophthalmoscope can be used to see all the named layers.
Within the named coats are flexible lens, aqueous humour, and vitreous body. The aqueous humour exists in two places, that is, the anterior chamber the posterior chamber. The location of the anterior chamber is between iris and cornea whereas the posterior chamber is placed between the iris and lens. The lens gets suspended in place by suspensory ligaments. The vitreous body is located behind lens.
The eyes are moved through tension and torque exerted by six different muscles in the organ. The muscles are inferior oblique, medial rectus, lateral rectus, medial rectus, superior oblique, and superior rectus. The globe experiences torque exerted by the muscles and undergoes pure rotation. Less than one millimeter of translation also occurs in the process.
Eyes suffer from a large number of conditions which are caused by different causes such as disease, age, and disorder. Aging causes some changes in eyes, which result in certain medical conditions. Some conditions occur in newborns without external causes. There are many types of eye specialists including opticians, optometrists, and ophthalmologists.
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