Thread by @theneurolander

Nystagmus series – Part VII
(seesaw & hemi-seesaw nystagmus)

“Maddox rod, double prism Maddox, red glass Maddox, Maddox cross, and Maddox wing”

British ophthalmologist Ernest Edmund Maddox (1863–1933)
(first report)

#MedTwitter #neurotwitter #EndNeurophobia #tweetorials

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Definition

“one half-cycle of elevation&intorsion of one eye
and
synchronous depression&extorsion of the other eye.
Next half-cycle,
vertical&torsional components are reversed”

- waveform: pendular (seesaw) & jerk (hemi-seesaw)
- hemi-seesaw: only one half-cycle

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Pathophysiology

Jerk (hemi-seesaw)
- lesion in the interstitial nucleus of Cajal

Pendular (seesaw)
- parasellar (midbrain compression & visual field defects)
- calibration lesion

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Fixation

Fixation in central vestibular nystagmus

“poorly suppressed by fixation of a visual target”

- abnormal smooth-pursuit system

https://twitter.com/theneurolander/status/1593997983409995776

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Associated symptoms

Hemi-seesaw nystagmus
- contralateral ocular tilt reaction
- central otolithic imbalance

Seesaw nystagmus
- visual field defect

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Considerations

Reversed congenital form
- elevation & extorsion
- dissociated vertical deviation

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Seesaw nystagmus – features

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Moran CORE

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Moran CORE

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Frederico Moura

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Raed Behbehani

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Lisa Koch

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Audiology-Vestibular Science Academy

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

youtube.com/shorts/oyuTlHw… via: Dr Pawan Prasher

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Neuroftalmologia em Foco

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Raed Behbehani

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Seesaw nystagmus

i) 🔄 elevation&intorsion w/ depression&extorsion
ii) no suppress by visual fixation

via: Dr Gamal Sobhy

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Hemi-seesaw nystagmus – features

i) elevation&intorsion w/ depression&extorsion
ii) only one half-cycle
iii) no suppress by visual fixation

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Hemi-seesaw nystagmus

i) elevation&intorsion w/ depression&extorsion
ii) only one half-cycle
iii) no suppress by visual fixation

doi.org/10.1017/cjn.20… via: Canadian Journal of Neurological Sciences

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Hemi-seesaw nystagmus

i) elevation&intorsion w/ depression&extorsion
ii) only one half-cycle
iii) no suppress by visual fixation

doi.org/10.1212/WNL.0b… via: Neurology

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Hemi-seesaw nystagmus

i) elevation&intorsion w/ depression&extorsion
ii) only one half-cycle
iii) no suppress by visual fixation

doi.org/10.1007/s00415… via: Journal of Neurology

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Hemi-seesaw nystagmus

i) elevation&intorsion w/ depression&extorsion
ii) only one half-cycle
iii) no suppress by visual fixation

doi.org/10.1016/j.jocn… via: Journal of Clinical Neuroscience

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Nystagmus general description

"Nystagmus – Moving eyes!!!"

https://twitter.com/theneurolander/status/1592278924826140672

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