Features of ocular bobbing:
(1) Both eyes move in a synchronous vertical arc, which may be a few millimeters.
(2) The eyes move downward or upward, returning to the primary position.
(3) It may be associated with pontine myoclonus.
Causes of ocular bobbing include:
(1) acute organophosphate poisoning
(2) combined phenothiazine and benzodiazepine poisoning (associated with reverse bobbing)
(3) encephalitis
(4) Leigh disease (subacute necrotizing encephalomyelopathy)
(5) pontine hemorrhage secondary to hypertension
(6) ruptured distal posterior inferior cerebellar artery aneurysm
(7) posterior fossa infarcion secondary to thrombosis of basilar, vertebral and/or middle cerebral arteries
(8) locked-in syndrome
(9) embolism to the anterior spinal artery
(10) other causes of advanced damage to the pons
Differential diagnosis:
(1) vertical nystagmus (nystagmus has fast and slow components)
