近視眼のvitreo-retino-ciliary barrier

Vitreo-retino-ciliary barrier in myopic eyes

（1）わが国ではもちろん，近年，世界中で近視が増加している．とくに若年者に増えているのは，おそらく近業に関係があると推定される．

（2）増えているのは軽度ないし中等度の近視であって，強度近視とは別物とする意見もある．しかし今回の成績から，近視の本態を2種類に区別することは不自然であるといえる．

（3）電気生理学的ならびに病理学的に，近視の毛様体，脈絡膜の障害が示されている．

（4）近視度ともっとも密接に関係するのは，硝子体腔の延長であって，このことは強度近視のみでなく，軽度近視にもみられる事実がある．

（5） vitreous fluorophotometryによって，近視における血液毛様体柵の障害が初めて明らかにされた．これは近視の程度ときわめてよく相関し，近視の初発症状と思われる．

（6）血液毛様体柵の障害が何故起こるのか不明であるが，その引き金となるのは持続調節であることが推定される．

We made a series of investigations into the pre-valence, causative factors and pathophysiological features related with myopia.

The incidence of myopia has been found to be on the increase in recent years, particularly among the younger generation throughout the world as well asin Japan. It is postulated that this increase is proba-bly related with near accommodation.

In contrast to the theory held by some that slight and moderate myopia differs from high myopia. Our findings suggest that it is not reasonable to clas-sify myopia into two groups.

We could prove the involvement of the ciliary body and the choroid in myopia based on pathologi-cal and electro-physiological findings. We could also prove that the elongation of the vitreous cavity was most closely related with the degree of myopia ranging from slight to high myopia.

Vitreous fluorometry has shown the breakdown of the blood-ciliary barrier even in early myopic eyes. The degree of breakdown was closely correlat-ed with the degree of myopia. The breakdown seem-ed to be one of the earliest changes to occur in myopia. While the cause of this breakdown awaits further elucidation, a long-term accommodation seemed to serve as a trigger.