濾過胞感染に対する硝子体手術の臨床的特徴と術後経過

Clinical features and postoperative course of vitrectomy for bleb-related infection

要約　目的：感染が硝子体内にまで及んだ濾過胞感染ステージⅢの診断で硝子体手術を行った症例の臨床的特徴と術後経過を報告する。

対象：2018年4月1日〜2022年2月28日の期間，マイトマイシンC併用線維柱帯切除術後の濾過胞感染ステージⅢに対して北里大学病院で硝子体手術を施行した12例14眼。

方法：濾過胞感染発症までの期間，感染の自覚症状発現から硝子体手術までの期間，硝子体手術の合併症，細菌培養結果，感染前後でのlogMARおよび眼圧の推移，硝子体術後に追加した緑内障手術・処置を調べた。

結果：線維柱帯切除術から感染発症までの期間は平均4.7年，感染の自覚症状発現から硝子体手術までの期間は平均2.2日，硝子体手術の合併症はなく，細菌培養陽性であった6眼中3眼（50.0％）からStreptococcus属が検出された。logMARは感染前0.59±0.76と比較し，感染時は1.47±0.52（p＝0.005）へ低下し，最終時点で感染前よりlogMAR 0.2以上悪化した症例は6眼（42.9％）で，うち2眼が失明した。眼圧は，感染前8.5±2.1mmHg，術後1か月14.0±5.4mmHg（p＝0.002）と，術後3か月11.7±3.6mmHg（p＝0.006）で上昇した。硝子体手術後に追加の緑内障手術・処置を行ったのは5眼（35.7％）であった。

結論：硝子体手術により濾過胞感染は沈静化したが，約4割は視力が悪化した。約4割の症例で追加の緑内障手術・処置が必要となった。

Abstract　Purpose：To report the clinical characteristics and postoperative course of a case where vitrectomy was performed on patient diagnosed with stage Ⅲ bleb-related infection after trabeculectomy.

Subjects：Fourteen eyes of 12 patients underwent vitrectomy at Kitasato University Hospital for stage Ⅲ bleb-related infection after trabeculectomy with mitomycin C from April 1, 2018 to February 28, 2022.

Methods：Time points such as the period between trabeculectomy and infection, and period between onset of subjective symptoms of infection and vitrectomy were noted. Complications of vitrectomy and results of the bacterial culture were examined. Additionally, logarithmic minimum angle of resolution（logMAR）, intraocular pressure（IOP）before and after infection, and additional glaucoma surgical procedures after vitrectomy were reported.

Results：The mean time from trabeculectomy to infection was 4.7 years and the mean time from the onset subjective symptoms to vitrectomy was 2.2 days. There were no vitrectomy complications. Three eyes（50％）showed positive bacterial cultures for the genus Streptococcus. LogMAR decreased from 0.59±0.76 before infection to 1.47±0.52（P＝0.005）at the time of infection, and 6 eyes（42.8％）had a logMAR worse than 0.2 at the final time point, including 2 eyes that were blind. IOP was 8.5±2.1 mmHg pre-infection, 14.0±5.4 mmHg 1 month postoperatively（P＝0.002）and 11.7±3.6 mmHg 3 months postoperatively（P＝0.006）. Five eyes（36％）underwent additional glaucoma surgical procedure after vitrectomy.

Conclusion：Vitrectomy caused the bleb-related infection to subside, but visual acuity worsened in about 40％ of the cases. Additional glaucoma surgical procedures were required in about 40％ of cases.