These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Large phase differences between L-cone- and M-cone-driven electroretinograms in retinitis pigmentosa.
    Author: Scholl HP, Kremers J.
    Journal: Invest Ophthalmol Vis Sci; 2000 Sep; 41(10):3225-33. PubMed ID: 10967087.
    Abstract:
    PURPOSE: To study the dynamics and interactions of the signals originating in the long- (L-) and middle (M)-wavelength-sensitive cone pathways in patients with retinitis pigmentosa (RP). METHODS: Twenty-six patients with RP and 29 normal subjects participated in the study. Electroretinographic (ERG) responses were measured to stimuli that modulated exclusively the L- or the M-cones or the two simultaneously (both in-phase and in counter-phase) with varying ratios of L- to M-cone contrasts. S-cones were not modulated. RESULTS: The data of the normal subjects and of the patients can be described by a model in which the amplitudes and the phases of the signals originating in the L- and M-cones are vector summed. In the RP patients, there was a general reduction in ERG sensitivity. The L-cone-driven ERG response was significantly delayed, whereas the M-cone-driven ERG response was phase advanced. CONCLUSIONS: Large dynamic differences between L- and M-cone-driven ERGs can be detected in RP. As a result, the interaction between the L- and M-cone systems, when modulated simultaneously at 30 Hz, is subtractive in RP patients and additive in normal subjects. Our data show that the use of only a standard white flicker ERG might lead to a misinterpretation of the mechanisms involved in retinal disorders, because the phases of different cone-driven responses are not considered.
    [Abstract] [Full Text] [Related] [New Search]