緑内障チューブシャント眼に対するDSAEKにおいて空気注入後の眼圧変動を追えた1例

A case of DSAEK in an eye with glaucoma tube shunt in which intraocular pressure normalized gradually after air injection

要約　目的：緑内障術後患者に対する角膜内皮移植（DSAEK）では空気注入時に前房圧が上がりにくく，移植片の接着に苦慮することが多い。今回，チューブシャント術後眼に対するDSAEK術後の移植片接着不良において再度空気注入を行った際，注入後の眼圧変動を経時的に計測できた1症例を経験したので報告する。

症例：患者は60歳台，男性。左眼の緑内障に対して過去6回の緑内障手術（線維柱帯切除術2回，濾過胞形成術2回，チューブシャント術2回）を受けている。左眼の水疱性角膜症に対しDSAEKを施行したところ，術後に移植片接着不良を認め，角膜縫合および空気注入を施行するも接着せず，再度空気注入を行った。2度目の空気注入は処置室で行い，仰臥位のまま経時的に手持ち眼圧計（iCare^®）で眼圧を計測した。空気注入直後は27mmHgであったが，35分後には19mmHgとなり，再度空気を注入し40mmHgとなった。さらに60分後には19mmHgとなり，空気を再注入した。合計160分仰臥位を続け，帰室した。その後，移植片は接着し，視力改善がみられたものの，術後1か月時の視野検査では術前と比べて周辺視野の狭窄が認められた。

結論：緑内障術後患者に対するDSAEKでは，空気注入後の比較的早期に眼圧が低下するため注意を要する。本症例では複数回の空気注入を要し，視力は向上したが，周辺視野に影響がみられた。

Abstract　Purpose：In corneal endothelium transplantation（DSAEK）for patients after glaucoma surgery, the anterior chamber pressure does not rise easily during air injection, and it is often difficult to adhere the graft. We report a case in which the intraocular pressure fluctuation after air injection could be measured over time when the injection was performed again when the graft adhesion failed after DSAEK in an eye after tube shunt.

Case：The case describes a 60-year-old man. He has undergone six glaucoma surgeries for the left eye（two trabeculectomy, two filtration bleb plasty, and two tube shunt surgeries）. When DSAEK was performed for bullous keratopathy in the left eye, postoperative graft adhesion failure occurred. Subsequently corneal suture and air injection were performed, but the graft did not adhere following which air injection was performed again. The second injection was performed in the treatment room, and the intraocular pressure was measured with a handheld tonometer（iCare^®）over time while the patient was in a supine position. Immediately after the air injection, the intraocular pressure was 27 mmHg, but after 35 minutes, it became 19 mmHg, and after injecting air again, it became 40 mmHg. After another 60 minutes, the intraocular pressure reached 19 mmHg, following which air was reinjected. He continued to maintain the supine position for a total of 160 minutes and returned to the room. Thereafter the graft was engrafted and the visual acuity improved. However a visual field test perfomed 1 month after the operation showed narrowing of the peripheral visual field compared to that before the operation.

Conclusion：In DSAEK for patients after glaucoma surgery, caution is required because the intraocular pressure decreases relatively early after air injection. In this case, multiple air injections were required, and although the visual acuity improved, the peripheral visual field was affected.