How does Chiari cause downbeat nystagmus?

Cerebellar tonsils. This is due to involvement of the central vestibular pathways, particularly at the level of the cerebellar tonsils, usually herniating at the foramen magnum in a Chiari (I) malformation.

Related Questions

Can Chiari cause positional downbeat nystagmus? Vestibular PT it's definitely not BPPV I also have DBN intermittently in all directions of gaze

Comments. Downbeat nystagmus is a sign of cerebellar/ brainstem connection pathology, and may or may not relate to an effect of the Chiari malformation. This needs further evaluation by a neuro-ophthalmologist, and perhaps a neurosurgeon who has prior EXPERTISE in Chiari, as can be associated with other problems. Read more...

If downbeat nystagmus causes stationary objects to move up/down & back/forth and slide would this be considered oscillopsia?

Possibly. Oscillopsia is The illusion of oscillation of the visual surroundings and is associated with certain neurological processes, most commonly meningitis. Nystagmus is a physical finding on examination. A person with nystagmus from birth would not be aware of oscillopsia whereas someone with acquired nystagmus might. . Read more...

Can migraine or vestibular migraine cause intermittent downbeat nystagmus in all directions of gaze?

Yes. Yes, and the problem is likely to have strong psychological cause. I suggest a review of the website www.stii.us. If what you learn there makes sense to you, look (on the website) for a clinician near you who is familiar with the method called Subliminal Therapy to determine if the problem is psychogenic. Read more...

What conditions cause downbeat nystagmus in all direction of gaze? The DBN cause my vision to "slip" and see stationary objects slide.

Jerk nystagmus . The four most frequent identifiable causes of downbeat nystagmus are cervico-medullary junction anomalies (Chiari malformation), cerebellar degenerations, multiple sclerosis, and vertebrobasilar infarction. Medications and alcohol are other relatively common causes. Uncommon causes include B12 deficiency and familial. An MRI should be done if you have not had one yet. Treatment is dalfampridine. Read more...

What conditions cause constant downbeat nystagmus? Brain herniation & tonsillar descent on brain & IAC MR dizzy headaches pressure induced symptoms

Disturbing signs... What you are describing are symptoms and signs of increased intracranial pressure from brain tumor or intracranial hypotension from spontaneous cerebrospinal fluid leak or Chiari Malformation. In other words, could be a lot of different things. You need to see a Neurosurgeon as the findings on your MRI are serious and may need surgery. Go and get a good and thorough and consultation. Read more...

What can cause positional downbeat nystagmus besides BPPV? 5mm tonsillar descent noted on MRI Headaches pulsatile tinnitus dizzy worse with pressure

Some possibilities. The list of possible causes of downbeat nystagmus that the neurologists and neuroophthalmologists think about include: Arnold-Chiari type I malformation, tumors (meningioma, cerebellar hemangioma) at the foramen magnum, demyelination, stroke, cranial trauma, drugs (alcohol, lithium, anticonvulsants), spinocerebellar degenerations, syrinx of the brainstem or upper cervical spinal cord, etc... Read more...

What is exophoria? Does it have any correlation with downbeat nystagmus?

Exophoria. is a tendency for the eyes to turn away from each other. It usually does not require treatment, unless there is eye strain with reading. It has no relationship to downbeat nystagmus which is a much more serious problem. Read more...