What the student is his health Size

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Updated December 16, 2014.

Written or reviewed by a board-certified physician. See About.com Examination Council.

Question: student Size

Why pupil size is important?

Answer: The size of the pupil, a physician can tell a lot about your health. The size of the student press is an important tool for unlocking potential medical problems in your body.

What is the student?

The pupil is the black circle in the center circle of the iris, the colored part of the eye. The pupil is actually a hole, sensitive to light passing through the light onto the retina at the back of the eye layer.

The student is similar to an opening in the machine to be controlled as much light you want in the camera.

The student can develop greater (dilate) or small contract (narrowing). His iris contains muscles which respond to external stimuli to control the amount of light on the retina. In bright light, the pupil constricts to reduce the amount of light in the eye. In the dark or low light conditions, the pupil dilates to more light into the eye allows to improve visibility. Normal pupil size tends to between 2.0 and 5.0 mm, depending on illumination. Pupil size is usually larger in younger people.

What is the size of the pupil can reveal?

When the doctor examined her students, he or she should seek anisocoria first. Anisocoria is a condition in which the size of the pupils are uneven. Twenty percent of the population is anisocoria normally and shows nothing unusual. In some cases, however, the extent of unequal pupils may be a sign for the disease.

Your doctor examines the size and shape of the pupil both light and darkness. Aware of the speed and quality of pupillary response to stimuli has also been noted.

Your doctor may also test your pupillary response to stimuli, such as small print next. All differences between the students is also observed.

The pupil is controlled by a very long nerve pathway in the body. The nerves that begins to control the students in the brain, and then moves down into the spinal cord above the upper lung, below the subclavian artery, neck and brain enhancements and finally moves close to the optic nerve and then to the students , Any disruption along this route could potentially cause effects on the nervous and changes in the response of the student.

What conditions can affect the size of the pupil?

abnormal pupil size can sometimes be a sign of illness. The following conditions may affect the size of the pupil:

• Glaucoma: A student in the medium may be a sign of glaucoma long.
• Aneurysm: An aneurysm is growing in certain blood vessels in the brain and dilated pupils cause other symptoms.
• Lung cancer: Lung cancer, which affects the upper lungs may affect students nerve fibers.
• Brain tumor: When a tumor or mass near the origin of nerve fibers student, it can cause problems in the pupil.
• Recreational use of drugs: Certain drugs can dilate the pupils or contract abnormally.
• Drugs: glaucoma and antihistamines can sometimes cause dilated pupils.
• Head injury: head injury or concussion may cause unequal pupils.
• Horton headache: Cluster headaches can cause constricted pupil.
• AVC: Sometimes a stroke can cause changes in pupil size.
• Syphilis: Syphilis can Argyll-Robertson pupil lead. Argyll-Robertson pupils are not responding small, misshapen unequal pupils contract with a certain emphasis, but usually on light.

How does pupil size measured?

Pupillometer Ophthalmologists use infrared to measure the size of the pupil. The device consists of a chamber in line for infrared detection and two infrared lamps to illuminate the student side.

How does pupil size affect LASIK?

People with large pupils are usually good candidates for LASIK and other refractive procedures. Naturally expands have pupils or pupils who could expand much in low light to increase the occurrence of glare and halos after Lasik. Measurement of pupil size is in deciding whether LASIK is right for you step important.

_Source:

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