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Corneal Reflex Test.

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Definition.

• Also known as the blink reflex, is an involuntary 

blinking of the eyelids elicited by stimulation of the

cornea (such as by touching or by a foreign body),

or bright light, though could result from any 

peripheral stimulus. Stimulation should elicit botha direct and consensual response (response of the

opposite eye). The reflex consumes a rapid rate of 

0.1 second. The evolutionary purpose of this reflex

is to protect the eyes from foreign bodies and brightlights (the latter known as the optical reflex).[1] The

blink reflex also occurs when sounds greater than

40-60 dB are made.

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Purpose.

• Reflex tests measure the presence

and strength of a number of 

reflexes. In so doing, they help toassess the integrity of the nerve

circuits involved.

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Related Disease.

• Acoustic neuroma.

• Bell's palsy.

• Brain stem infarction or injury.

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Corneal Light Reflex. 

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Definition.

•  The pupillary light reflex is a reflex that controls

the diameter of the pupil, in response to the

intensity (luminance) of light that falls on the

retina of the eye, thereby assisting in adaptation to

various levels of darkness and light, in addition toretinal sensitivity. Greater intensity light causes

the pupil to become smaller (allowing less light in),

whereas lower intensity light causes the pupil to

become larger (allowing more light in). Thus, thepupillary light reflex regulates the intensity of light

entering the eye.

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Purpose.

• Reflex tests are performed as

part of a neurological exam,

either a "mini-exam" done toquickly confirm integrity of the

spinal cord, or a more

complete exam. 

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Related Disease.

• Guillain-Barre syndrome

• Herpetic keratoconjunctivits

•

Trigeminal neuralgia• Premature birth

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Ocular Motility Test.

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Definition.

•  The ocular motility subspecialty examines

impairment of eye movements resulting from

malfunction of the sensory-motor mechanism of 

the eye which leads to faulty alignment of the

eyes and/or visual impairment. Disease may 

affect the oculomotor (CNIII), trochlear (CNIV)

and abducens (CNVI) nerves directly, the

brainstem nuclei corresponding to the nerve, or

produced by dysfunction of higher order sensory and motor systems.

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Purpose.

• Performed to diagnose the

presence and location of spinal

cord injury or neuromusculardisease. 

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Related Disease.

• The ocular motility defects seen are

defined by their abnormality of 

movement such as esotropia,

esophoria, exotropia, exophoria,hypertropia, hypotropia, or often by 

eponymous names such as Duane's or

Brown's.