Brain herniation and eye movement - Page 2Register Today!
- Oct 21, '11 by GrnTeaAnd so long as we're at it, here's one more weird eye-movement thing associated with brains, or lack thereof. Cold calorics testing-- used to do this all the time with potential organ donors. Also had the interesting experience of feeling what this is like when my doc irrigated my ear with alcohol....cooooolllldddd.... and I felt my eyes jerrk uncontrollably. Weird.
From the Wikipedia:
It is commonly used by physicians, audiologists and other trained professionals to validate a diagnosis of asymmetric function in the peripheral vestibular system. Calorics are usually a subtest of the electronystagmography (ENG) battery of tests. It is one of several tests which can be used to test for brain stem death.
One novel use of this test has been to provide temporary pain relief from phantom limb pains in amputees  and paraplegics. It can also induce a temporary remission of anosognosia, the visual and personal aspects of hemispatial neglect, hemianesthesia, and other consequences of right hemispheric damage.
 Technique and results
Cold or warm water or air is irrigated into the external auditory canal, usually using a syringe. The temperature difference between the body and the injected water creates a convective current in the endolymph of the nearby horizontal semicircular canal. Hot and cold water produce currents in opposite directions and therefore a horizontal nystagmus in opposite directions. In patients with an intact brainstem:
- If the water is warm (44°C or above) endolymph in the ipsilateral horizontal canal rises, causing an increased rate of firing in the vestibular afferent nerve. This situation mimics a head turn to the ipsilateral side. Both eyes will turn toward the contralateral ear, with horizontal nystagmus to the ipsilateral ear.
- If the water is cold, relative to body temperature (30°C or below), the endolymph falls within the semicircular canal, decreasing the rate of vestibular afferent firing. The eyes then turn toward the ipsilateral ear, with horizontal nystagmus (quick horizontal eye movements) to the contralateral ear.
- Absent reactive eye movement suggests vestibular weakness of the horizontal semicircular canal of the side being stimulated.
In comatose patients with cerebral damage, the fast phase of nystagmus will be absent as this is controlled by the cerebrum. As a result, using cold water irrigation will result in deviation of the eyes toward the ear being irrigated. If both phases are absent, this suggests the patient's brainstem reflexes are also damaged and carries a very poor prognosis.
Mnemonic One mnemonic used to remember the FAST direction of nystagmus is COWS.
COWS: Cold Opposite, Warm Same.
Cold water = FAST phase of nystagmus to the side Opposite from the cold water filled ear
Warm water = FAST phase of nystagmus to the Same side as the warm water filled ear
In other words: Contralateral when cold is applied and ipsilateral when warm is applied
- Oct 21, '11 by tewdleswow esme, that was a nice comprehensive review!
- Oct 21, '11 by TonyaM73Thank you Esme! Everyone was a little freaked out by the eye movement last night and what that meant to the nursing care. We knew what was happening, but none of us had actually seen someone's eyes do that before.
Very, Very sad case.
- Oct 21, '11 by EricJRNFor more search results, you might also look at periodic alternating gaze.
- Oct 21, '11 by Esme12Quote from tewdlesThanks....I love my critical care....wow esme, that was a nice comprehensive review!
- Oct 21, '11 by nerdtonurse?Quote from TonyaM73Approximately 20 ft fall out of deer stand and crossbow fired into the back of the pt's head. It's been a while, but what I remember now is that the cerebellum took a hit as the bolt transversed the brain. He made it to us, breathing about 4x minute, eyes going crazy, herniating, bad stuff all around, had fractured pelvis, leg, ribs, etc.. I assumed the rapid eye motions were the equivalent of a stroke victim "looking" at the stroke site, as this guy's brain was tore up. I don't remember the exact areas, but if "Oopsied beyond all repair" was a Nanda diagnosis, this guy would have gotten it.Everything that I am looking up mentions nystamus or abscent upward movement of the eye, but nothing that really describes what I was seeing.
Nerdtonurse, what was the diagnosis with your pt?
The only thing that should come out of a nose is air, snot or an NG tube.
and BTW, I wish I worked with Esme!
- Oct 22, '11 by nola1202Quote from TonyaM73oh ewwww. I think I just reached my gross out point. I have never seen anything like this, my few neuro pt's went to surg or recovered to some extent. Still glad for the info. thanks.actually her head was perfectly stationary. I thought that doll's eye reflex was only when you turned the pt's head and their eyes still looked forward rather than the normal responce which is to turn the eyes to the opposite side of the way the head is turned.
I think that I found my answer. From what I was reading it is Ping Pong gaze and when it stops is when the herniation reaches the brain stem and the pts die soon afterward.
- Oct 22, '11 by xtxrnIf I remember right, caloric testing can also induce vomiting in some folks.
- Oct 22, '11 by TonyaM73I wish I worked with Esme too!! I think I'd learn a lot!