A patient may be diagnosed with a<unk>  by a physician performing a number of tests to examine the patient's eye movement abilities. In most cases, the<unk>  palsy can simply be seen by inability to move both eyes in one direction. However, sometimes a patient exhibits an abduction nystagmus in both eyes, indicating evidence of a<unk> . A nystagmus is a back and forth "jerk" of the eye when attempting to hold a<unk>  in one direction. Classification<unk> es can be classified into palsies affecting horizontal<unk>  and vertical<unk> . Horizontal<unk>  palsies Horizontal<unk>  palsies affect<unk>  of both eyes either toward or away from the midline of the body. Horizontal<unk>  palsies are generally caused by a lesion in the brain stem and connecting nerves, normally in the pons. Progressive scoliosis Horizontal<unk>  palsy with progressive scoliosis (HGPPS) is a very rare form of<unk> , appearing only in a few dozen families worldwide. HGPPS prevents horizontal movement of both eyes, causing people with this condition to have to move their head to see moving objects. In addition to the eye movement impairment, HGPPS is coupled with progressive scoliosis, although eye symptoms usually appear before scoliosis. HGPPS is caused by a mutation in the ROBO3 gene, which is important in cross-over of motor and sensory signals, preventing horizontal eye movement. In addition to the mutation, lesions in the midbrain and pons are common. This can also include a complete absence of a formation in the pons, the facial colliculus, which is responsible for some facial movements. The cause of progressive scoliosisin HGPPS and why HGPPS does not affect vertical<unk>  is unclear. Progressive scoliosis is normally treated with surgery. Vertical<unk>  palsies Vertical<unk>  palsies affect movement of one or both eyes either in upward direction, up and down direction, or more rarely only downward direction. Very rarely only movement of one eye in one direction is affected, although by definition this is not a<unk> , because by definition<unk> es affect movement of both eyes. Vertical<unk>  palsies are often caused by lesions to the midbrain due to a stroke or a tumor. In the case that only downward<unk>  is affected, the cause is normally progressive supranuclear palsy.
Conjugate gaze palsy
Horizontal gaze palsy
Pendular nystagmus
Bruns nystagmus
Ocular dysmetria
Cyclotropia
Conjugate eye movement
Esotropia