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VEP interpretation 1
Visual evoked potential interpretation 1
| Question | Answer |
|---|---|
| Binocular absence of VEPs | Technical problems; ocular abnormalities; lack of fixation or acuity; severe bilateral optic nerve defects |
| Monocular absence of VEPs | Optic neuropathy, ocular diosrders |
| Prolonged VEP latency | optic nerve lesion |
| Increased VEP latency | Optic nerve lesion |
| Increased interocular VEP latency difference | Optic nerve lesion |
| Monocular decreased VEP amplitude | Ocular lesion |
| Binocular decreased VEP amplitude | Ocular lesions or chiasmal lesion, any bilateral prechiasmal or chiasmal lesion; low amplitude with normal latencies may be normal |
| Abnormal bilateral temporal VEPs | lesion at or near the optic chiasm |
| Abnormal corresponding field VEPS | Lesion of the posterior visual pathways, the optic radiations or visual cortex |
| Abnormal monocular hemifield VEP | Incomplete optic nerve lesion |
| Pattern reversal VEP abnormalities with neurologic lesions in the ocular region | Absence of VEP, low amplitude VEP |
| Pattern reversal VEP abnormalities with neurologic lesions in the optic nerve region | Absence of VEP, increased full field VEP latency, increased interside VEP latency difference |
| Pattern reversal VEP abnormalities with neurologic lesions in the optic chiasm region | Abnormal bilateral full field VEP, bilateral temporal half-field VEP |
| Pattern reversal VEP abnormalities with neurologic lesions in the optic tract | Abnormal bilateral corresponding half-field VEP; full field VEP may be normal |
| Pattern reversal VEP abnormalities with neurologic lesions in the occipital cortex | Abnormal bilateral corresponding half field VEP; full field VEP may be normal |