Why do we blink?
Blinking is a normal reflex that protects the eye from dryness, bright light, and fingers or other objects coming towards it. Blinking also regulates tears, which nourish and cleanse the surface of the eye The blinking rate in newborns is only 2 times per minute. This increases to 14-17 times per minute in adolescence and remains at this rate through the remainder of life. Blinking can also increase in response to pain, bright light, changes in temperature and humidity, and conversation.
What is excessive blinking?
Excessive blinking is blinking that seems more frequent than typical. It can involve one or both eyes. It may seem more forceful than normal. It may also be associated with other movements (tics) of the face, head or neck.
What causes excessive blinking?
Excessive blinking can be caused by problems with the eyelids or anterior segment (front surface of the eye), habitual tics, refractive error (need for glasses), intermittent exotropia or turning out of the eye, and stress. It is very rare for excessive blinking to be a sign of an undiagnosed neurologic disorder.
How should excessive blinking be evaluated?
A pediatric ophthalmologist will be able to diagnose the cause of the symptoms. A thorough exam will be performed. If there is a problem such as an ingrown eyelash, corneal abrasion (scratch on the front surface of the eye), conjunctivitis (pink eye), foreign body in the eye, or eye dryness, this can easily be diagnosed by performing an examination with an instrument called a slit lamp. This is a special microscope used to magnify the eye. If glasses are needed, this can also be easily detected. Any strabismus (in turning or out turning of the eye) will be diagnosed when the ophthalmologist examines the eye movements.
How is excessive blinking treated?
If an abrasion or conjunctivitis is diagnosed, eye drops or ointment may be given. Glasses may be prescribed if the excessive blinking is caused by blurry vision.
What is a habitual tic?
A habitual tic is a small, voluntary body movement. It may be caused by, among other things, stress, fatigue or boredom. It usually affects both eyes at the same time. It affects boys twice as often as girls, with the average age of 5 years when it first appears. It is a benign condition that will resolve without treatment, usually within weeks to years, often recurring intermittently. There is no neurologic cause, and further evaluation and brain scans are not necessary. If the child displays multiple tics and/or auditory (vocal) tics, an appointment with a Neurologist is indicated.
Credits: Journal of American Association for Pediatric Ophthalmology and Strabismus