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Visual field mean deviation and relevant factors in 928 Chinese retinitis pigmentosa patients
1Department of Ophthalmology, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
Aim:
To investigate the associations between demographic and clinical factors with the rate of visual field mean derivation (MD) decline in retinitis pigmentosa (RP) patients.
Methods:
Correlations of MDs with the visual acuity and retinal pigmentation were analyzed in 928 RP patients. MD decreasing rate in 10y and potential influences of gender, age, family history and retinal pigmentation on the rate were explored in 201 RP patients.
Results:
In the 928 patients, average MD and visual acuity were -14.44±8.61 dB and 0.79±0.35 respectively and when MD was lower than -9.18 dB the visual acuity would be below 1.0 (20/20). The average MD medium between eyes with or without retinal pigmentation was -14.82 dB. In 123 non-pigmented eyes, the average MD were lower than the medium but in 153 pigmented eyes it was higher than that. In the 201 patients, the average decreasing value of MD in 10 years' period was -8.01±3.66 dB and the value were correlated to retinal pigmentation but not to gender, age or RP family history.
Conclusion:
The rate of MD decline in RP eyes is significantly related to retinal pigmentation. Our study demonstrates the quantitative rate of MD decline in RP patients and the value of MD could well reflect the severity of RP.
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