NEONATAL EYE REFLEXES

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BLINK REFLEXES

Visuopalperbral reflex or Dazzle reflex:

Immediate blinking of eyes when a bright light is shown to the eyes.


Cochleopalpebral reflex:

Sudden blinking of eye due to a loud sound or tensing of eyelids if eyelids are closed.

Cutaneopalpebral reflex:

Immediate blinking of eyes in response to painful touch.

Nasopalpebral reflex:

Blinking when nasal bridge is tapped.

Peiper's optic reflex:

Opisthotonus when a bright light shines the eyes.

Ciliary reflex is blinking on stroking the eyelashes.

Corneal reflex is blinking of eyes whrn cornea is touched.

McCarthy's reflex:

Homolateral blinking on tapping the supraorbital area. In abnormal cases, the blinkin occurs when tapped at a distant area from supraorbital area. e.g. vertex of skull.

If the reflex is difficult to elicit in case of closed eyes, stimulation of perioral area can stimulate the baby to open the eyes thus the test can be done easily.

The satisfactory demonstration of blink reflex indicate that cerebral depression is unlikely and the appropriate muscles can contract.



DOLL'S EYE RESPONSE

The delay in the movement of eyes after the head has been turned. That is if the head is turned to the right the eyes do not point to the right.

This reflex is present in first 10 days of life and then disappears as fixation develops.

It can persist for longer duration in case of abnormal babies.

Image result for funny baby clipart
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RESPONSE TO ROTATION
Peiper first decribed the idea of rotational nystagmus.

The examiner holds the baby  facing him and tilted at 30 degrees. He then spins 2 or 3 times. During the rotation the eyes deviate in the direction of movement; on stopping they deviate in reverse direction and coarse nystagmus occurs.

This test depens on vestibular function and helps in identifying ocular palsies.

PUPIL REFLEX:

The pupils react to light, but in preterm and some full term babies the duration of exposure to light is prolonged to elicit the reflex.

The light shouldn't be very bright as it may close the eyes.

Photic sneeze reflex:

A sneeze when bright light is shone into the eyes.

Resistance to passive opening of eyes is present since birth.




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