retraction nystagmus meaning
Involuntary movements of the eye that are divided into two types,jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction,and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al.,Principles of Neurology,6th ed,p272)
- Retraction nystagmus and convergence movement are usually improved with this procedure as well.
- Frequently, paralysis of upward gaze along with several ocular findings such as convergence retraction nystagmus and eyelid retraction also known as Collier's sign and Light Near Dissociation ( pupil accommodates but doesn't react to light ) are known collectively as Parinaud's syndrome or Dorsal Mid-brain syndrome, are the only physical symptoms seen.