黄斑部脈絡膜循環の日内変動

Diurnal variations of submacular choroidal circulation

（17-D-16）　広角レーザースペックルフローグラフイを用いて，正常人6例6眼の黄斑部と視神経乳頭周囲の脈絡膜の血流速度の日内変動を測定した。血流速度の相対値としてSBR値（square blur rate）を用いた。測定は4時間おきに6回行った。血圧，眼圧，脈拍を同時に測定し，それら相互の相関を求めた。黄斑部には29.1％，乳頭周囲には19.0％の日内変動があった。各部位でのSBR値は，平均血圧および眼灌流圧と有意な相関があり，相関係数は，黄斑部でそれぞれ0.53と0.56，乳頭周囲で0.44と0.36であつた。各部位でのSBR値と眼圧，脈拍との間には相関はなかった。これらの結果から，脈絡膜循環には日内変動があることが証明された。

We quantitated the circulation in the submacular and juxtapapillary choroid in 6 eyes of 6 healthy volunteers using a laser speckle flowgraphy. The square blur rate (SBR) value served as index of blood flow velocity. Measurement was made every 4 hours over a 24-hour period in each eye. We also monitored the systemic blood pressure, intraocular pressure and the heart rate. The diurnal variation in the submacular and juxtapapillary choroid averaged 29.1% and 19.0% respectively. The SBR value was positively correlated with the average systemic blood pressure and the ocular perfusion pressure at the correlation coefficient of 0.53 and 0.56 respectively in the submacular choroid and of 0.44 and 0.36 respectively in the juxtapapillary choroid. The SBR value was independent of the intraocular pressure or the heart rate. The findings show the presence of diurnal variation in the choroidal circulation in human eyes.