Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1988-6-2
pubmed:abstractText
The pattern electroretinogram (PERG) and visual evoked potential (PVEP) were recorded simultaneously using a 1.1 cpd pattern which was counterphase modulated at 1 Hz. The responses of ocular hypertensive (OHT) eyes (with normal visual fields) and eyes with early glaucoma (with early visual field defects and/or early cupping of the optic nervehead) were compared to age-matched normal observers. All patients (26 eyes) and normal observers (14 eyes) had normal transient flash electroretinograms. Delays were seen in mean PERG latency in both OHT and early glaucoma eyes, while mean PERG amplitude was significantly reduced only in the early glaucoma eyes. The PVEP responses were 'unmeasurable' in 11/26 patient eyes because the waveforms were grossly abnormal in shape, making it impossible to identify the N- and P-components. The data were categorized in this manner: a patient response was considered abnormal if latency or amplitude exceeded normal limits (PERG or PVEP) or if the waveform was 'unmeasurable' due to its shape (PVEP only). Of the 26 patient eyes, we found that 8 eyes had normal PERG and PVEP, 11 eyes had abnormal PERG and PVEP, one eye had an abnormal PERG and a normal PVEP, and 6 eyes (3 patients) had a normal PERG and an abnormal PVEP. These data support the proposition that foveal vision (as assessed by the PVEP) may be affected by early glaucomatous damage. The relationship between the PERG and PVEP also was evaluated using a new measurement which we call the 'latency window'. Using this measurement, 15/26 patient eyes were abnormal-9 of these had 'unmeasurable' PVEPs. This measurement could be useful in classifying 'W'-shaped PVEPs as normal or abnormal.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0012-4486
pubmed:author
pubmed:issnType
Print
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
281-301
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Electrophysiological evidence that early glaucoma affects foveal vision.
pubmed:affiliation
Department of Ophthalmology, Mount Sinai School of Medicine, New York City, NY.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Case Reports, Research Support, Non-U.S. Gov't