格子状変性のある裂孔原性網膜剥離と後部硝子体剥離

Incidence of posterior vitreous detachment in rhegmatogenous retinal detachment associated with lattice degeneration

　格子状変性を有する裂孔原性網膜剥離422眼について，裂孔の形態と後部硝子体剥離との関係を検索した。年齢分布は，20代に小さな山と60代に大きな山のある2峰性を示した。30歳以下（67眼）では，硝子体は87％で未剥離で，ほとんどが萎縮円孔であった。屈折は近視（平均−7D）傾向を示した。剥離の高さは一般に低かった。51歳以上（239眼）では，硝子体は90％で剥離していた。原因病巣は，弁状裂孔が多く，正視で，剥離が高いことを特徴とした。31〜50歳では両者の中間に位置した。網膜剥離は，高齢者では硝子体剥離に伴う網膜裂孔から生じること，若年者では硝子体が未剥離の状態で発症することが明らかになった。後者の場合，網膜下液の供給源は液化硝子体であり，格子状変性前方の硝子体液化腔が，それが萎縮円孔に達する通路となると推測された。

We evaluated 422 eyes of 404 patients with rhegmatogenous retinal detachment associated with lattice degeneration. We paid particular attention to the shape of retinal breaks as related to posterior vitreous detachment (PVD). The age distribution showed two peaks: a small peak in the twenties and a big peak in the sixties. Retinal detachment in patients younger than 30 years were frequently due to atrophic holes. PVD was present in only 9 of 67 eyes (13%) in this group. Myopia was prevalent, average diopters. Retinal detachment in patients older than 51 years was usually bullous and was frequently due to retinal tears. PVD was present in 216 of 239 eyes (90% ) . The majority was emmetropic. Patients between 31 and 50 years showed mixed characteristics. The findings show that PVD is frequently present in retinal detachment in aged patients and absent in younger patients. Locally liquefied vitreous lacuna seemed to be the source of subretinal fluid through atrophic holes in the latter.