青光眼病人明點及暗點視野之比較

本篇首次以暗點視標測試青光眼病人網膜中央抑制節細胞視野之變化，此觀念有別於傳統視野計以亮點視標測試中央激發節細胞之視野變化。我們以“微電腦灰度中心視野計”程式，在IBM PC/AT相容個人電腦及19吋VAG顯示器上控制背景及視標之亮度，以TITAN KD-3000數位板控制視標之位置，模擬Octopus program 32進行測試。以背景亮度4Asb，視標亮度7Asb，視標犬小0.43°，測試距離26cm及動態方式，測試病人中心30°之亮點視野。以背景亮度222Asb，視標亮度196、187及168Aob測試暗點視野。共測試10位青光眼病人。結果顯示青光眼病人之亮點及暗點視野變化並與不同。我們推論網膜中央激發及中央抑制節細胞對青光眼的感受性是一樣的。我們建議將暗點視野測試配合自動現野計之檢測策略，以更多的灰度測試各種不同青光眼的視野變化，以期早期診斷及治療。

關鍵字

無資料

並列摘要

We present the first attempt to use dark point in visual field test. Contrary to the conventional bright spot, which measures the defect of on-centered ganglion cells, dark spot detects the damage of off-centered retinal ganglion cells. We sketched and compared the visual field in glaucomatous patients by 60th methods. On IBM PC/AT and 19 inch VGA monitor, we got 64 grey levels for both test spot and background. Digitizer was used to stimulate the kinetic recording method. For bright spot test, the background was 4 asb, the target 7 asb and target size 0.43 degree. For dark spot test, the background was 222 asb. Three target luminances of 196, 187 and 168 asb were tried. We tested the central 30 degree visual field on 10 glaucomatous patients. The result showed no remarkable difference between dark and bright spot visual fields. In other word, on-center and offcenter ganglion cells were damaged equally in glaucoma. We suggest (1) the combination of the concept of dark spot with automatic strategies of computerizd visual field tester, (2) varied spot size in correspondence to the size of receptive field, (3) same background luminance for both dark spot and bright spot visual field tests, and (4) more glaucomatous cases of individual categories to find the possible value of early diagnosis and early treatment.

並列關鍵字

Glaucoma ； Receptive field ； Visual field

國際替代計量

青光眼病人明點及暗點視野之比較

全文下載

主題瀏覽