Mydriasis

Mydriasis is a harmless condition characterized by the dilation of pupils. The black opening occurring in the middle of the eye is known as the pupil. It allows light that arrives at the eye to pass through to the retina which is located behind the eyeball. This process permits us to see everything that is around us. Dilated pupils or mydriasis is defined as a condition wherein the pupils have widened or expanded beyond its original size.

People who remain in a dark environment for prolonged periods will commonly experience dilated pupils. However, the pupils will become normal again after exposure to normal light. Dilation of pupils is a natural reaction of the eyes towards less or dim light. The pupils stretch under dark conditions so as to permit more light to enter the eyes and thus increase the visibility. Individuals who experience dilated pupils even under normal light conditions are probably suffering from an underlying disorder.

Causes of mydriasis

There are many reasons why a person may suffer from mydriasis or dilated pupils. A few of the causes may be serious while others are harmless or temporary. The most common causes of mydriasis are discussed below:

• Mydriatics: They are medicinal eye drops. They are usually administered by an ophthalmologist or an eye doctor before examining the eye. Use of mydriatics allow doctors to properly inspect the structure of the eyes. Its use can result in dilated pupils or mydriasis.
• Trauma or injury to the head: Dilated pupils or mydriasis is also noticeable after a stroke, head concussion, or epilepsy. Patients affected by these conditions not only elicit dilated pupils, but also do not experience any reaction to light.
• Side effects of medications: Individuals may also experience mydriasis or dilated pupils after consumption of certain prescription or illegal drugs. Muscle relaxants, antidepressants and other prescription medications can result in widened pupils. Also, users of marijuana, cocaine, and hallucinogenic drugs also tend to have dilated pupils.
• Contact with toxic chemicals or poison: When the eyes are exposed to harmful chemical or poisonous plants, then there may be enlargement of the pupils.
• Psychological stimuli: It may be noted that movement of the iris muscles which are located around the pupils are regulated by the central nervous system. Hence, any form of psychological stimuli such as excitement, sexual arousal, fear, etc. can result in contraction of these muscles, leading to mydriasis or dilated pupils.

Treatment of mydriasis

Treatment of mydriasis is focused at finding the underlying cause and then treating it.

• Mydriasis which is caused due to head trauma or injury needs immediate medical attention. Patients who suffer from dilated pupils due to injuries to the head are usually treated in the emergency room. An MRI scan is used to detect the seriousness of the brain injury, after which a suitable course of treatment is taken up.  A few patients may also require surgical intervention.
• Mydriasis or dilated pupils caused as a side effect of medications requires consultation with a doctor. The drug may need to be changed. Addicts of illegal drugs can resolve mydriasis by joining a rehab center.
• People who have suffered a stroke are given life support measures. Further medical treatment is given so to as to reduce the risk to additional brain damage.
• It may be noted that chronic irritation of the eyes along with dilated pupils may be an indication of ocular infections. Prescription eye drops can be used to treat such infections.
• Meningitis is a kind of bacterial infection which affects the spinal cord and brain. This disease is cured with antibiotics. Cortisone injections are also administered to reduce the swelling in the brain.
• Some individuals may suffer from mydriasis without any underlying cause. In such cases, doctors may recommend specific eye drops which help in constriction the enlarged pupils.

Self-care and prevention of mydriasis

• People generally tend to rub their eyes intensely when some foreign substances enter the eyes and cause irritation. This can then lead to dilated pupils or mydriasis. The irritation in the eyes can be eased with the use of over-the-counter moisturizing eye drops
• Dilated pupils or mydriasis caused due to psychological stimuli such as excitement or fear can be alleviated by engaging in relaxation techniques. After you have relaxed completely, the pupils return to their normal size. It is believed that tension in the stomach muscles is a major cause of psychologically induced cases of mydriasis. Hence, patients should try relaxing the stomach muscles.
• People with dilated pupils can aggravate the condition when they focus on distant items. Instead, patients should try to concentrate on nearby objects to reduce the strain on the eyes. This can also aid in the constriction of the enlarged pupils.
• Moving to a well-lit area can prevent further dilation of the pupils. Avoid dimly-lit rooms till mydriasis is completely resolved.
• Cover the eyes with sunglasses when outdoors. It will protect the eyes from the harmful rays of the sun