BÀI TẬP HÔN MÊ Ocular bobbingRapid, conjugate, downward movement; slow return to primary position; reflex horizontal eye movements are usually absentPontine strokes, other brainstem or cerebellar structural causes, metabolic or toxic Term disorders Summ ary of some rare types of spontaneous eye movements Rapid upward Slow downward movement; Unreliable for localisation; follows hypoxic movement; rapid return to primary insult or metabolic disorder slow return to position primary positionUnrelia ble for localisation; may occur with metabolic disordersOcula r dipping or inverse ocular bobbingDescrip tionCauses Reverse ocular Slow upward movement; dipping or rapid return to primary converse ocular position bobbingReverse ocular bobbing Unreliable for localisation; pontine infarction and in AIDS Ping pong gaze Horizontal conjugate deviation of the eyes, alternating every few seconds Bilateral cerebral hemispheric dysfunction; rarely posterior fossa hemorrhage Periodic Horizontal conjugate alternating gaze deviation of the eyes; alternating every two minutes Hepatic encephalopathy; disorders causing periodic alternating nystagmus and unconsciousness Vertical nystagmus Pontine strokes Vertical pendular oscillations; 2-3 cycles per second Clinical approach to the comatose patient ? ... Summ ary of some rare types of spontaneous eye movements Rapid upward Slow downward movement; Unreliable for localisation; follows hypoxic movement; rapid return to primary insult or metabolic disorder... positionUnrelia ble for localisation; may occur with metabolic disordersOcula r dipping or inverse ocular bobbingDescrip tionCauses Reverse ocular Slow upward movement; dipping or rapid return to primary