分層黄斑円孔に対する硝子体術後の視力と中心網膜厚の検討

Evaluation of visual acuity and central retinal thickness after vitreous surgery for lamellar macular hole

要約　目的：分層黄斑円孔に対し硝子体手術を施行し，術後の視力と中心網膜厚の変化について検討した。

対象と方法：当院で硝子体手術を施行した分層黄斑円孔症例のうち，術後4週間以上経過観察できた46例48眼を対象とした。術前後の最高矯正視力（logMAR視力）と中心網膜厚（CRT）を比較した。さらに，牽引型・変性型・混合型の3群に分類し比較検討した。

結果：性別は男性12例，女性34例，平均年齢は68.8±8.2歳，術後平均観察期間は16.6±21.5か月であった。logMAR視力は術前0.24±0.17から術後0.06±0.14に，CRTは術前353.5±86.8μmから術後314.6±62.5μmにそれぞれ有意に改善した（各p＜0.001）。牽引型（29眼）では，logMAR視力とCRTはともに有意な改善を認めたが（各p＜0.001），変性型（16眼）では，logMAR視力に有意な改善は認めたものの（p＝0.008），CRTで有意な変化はなかった（p＝0.96）。変性型では，術前12眼にellipsoid zone（EZ）の不整を認め，術後8眼でEZが改善，2眼で悪化，2眼で不変であった。

結論：本症に対する硝子体手術は，視力改善に有効な治療法であると考えられた。牽引型ではCRTは有意に改善したが，変性型ではCRTの改善はえられなかった。

Abstract　Purpose：To investigate the effect of vitreous surgery for lamellar macular holes（LMH）.

Methods：This is a retrospective observational case series with 48 eyes of 46 patients who underwent vitreous surgery for LMH and were followed for at least four weeks. They were classified into three groups, a tractional type, a degenerative type and a mixed type. Best-corrected visual acuity（BCVA）and central retinal thickness（CRT）were evaluated before and after vitreous surgery and compared between groups.

Results：Twelve patients were male and 34 were female. The mean age was 68.8±8.2 years. The mean follow-up period after surgery was 16.6±21.5 months. The mean BCVA significantly increased after surgery from 0.24±0.17 logMAR to 0.06±0.14 logMAR at last visit（p＜0.001）. The mean CRT significantly decreased from 353.5±86.8 μm to 314.6±62.5 μm（p＜0.001）. In the tractional type group（29 eyes）, both BCVA and CRT significantly improved（p＜0.001, respectively）. In contrast, the degenerative type group（16 eyes）showed a significant improvement in BCVA（p＝0.008）but no substantial change in CRT（p＝0.96）. In the degenerative type group, ellipsoid zone（EZ）disruptions were observed in 12 eyes preoperatively；they improved in 8 eyes, did not change in 2 eyes and deteriorated in 2 eyes postoperatively.

Conclusion：Vitreous surgery for LMH may be an effective treatment for improving visual acuity in any type of LMH. CRT may not improve in the degenerative type.