Department of Ophthalmology, Gavin Hebert Eye Institute, University of California, Irvine, CA, USA.
Department of Biomedical Engineering, University of California, Irvine, CA, USA.
Transl Vis Sci Technol. 2024 Oct 1;13(10):9. doi: 10.1167/tvst.13.10.9.
This study assessed the safety and efficacy of transepithelial crosslinking (CXL) using femtosecond (FS) laser-machined epithelial microchannels (MCs) followed by UVA CXL compared to FS laser (NLO CXL) in rabbits.
The epithelium of 36 rabbits was machined to create 2- by 25-µm MCs at 400 MCs/mm2. Eyes were treated with 1% riboflavin (Rf) solution for 30 minutes, rinsed, and then crosslinked using UVA or NLO CXL. Rabbits were monitored by epithelial staining, optical coherence tomography (OCT) imaging, and esthesiometry. After sacrifice at 2, 4, or 8 weeks, corneas were examined for collagen autofluorescence and immunohistochemistry.
NLO CXL showed no epithelial damage compared to UVA CXL, which produced on average 23.89 ± 5.6 mm2 epithelial defects that healed by day 3. UVA CXL also produced loss of corneal sensitivity averaging 0.83 ± 0.24 cm force to elicit a blink response that persisted for 28 days and remained significantly lower than control or NLO CXL. OCT imaging detected the presence of a demarcation line only following UVA CXL but not NLO CXL.
Even with improved transepithelial Rf penetration, UVA CXL resulted in severe epithelial damage, loss of corneal sensitivity, and delayed wound healing persisting for a month. When MCs were paired with NLO CXL, however, these issues were mostly negated. This suggests that MC NLO CXL can achieve a faster visual recovery without postoperative pain or risk of infection.
UVA CXL is a successful procedure, but there is a need for a transepithelial protocol. The combination of MCs and NLO CXL is able to keep the benefits of UVA CXL without causing epithelial damage.
本研究评估了使用飞秒（FS）激光制造的上皮微通道（MCs）进行经上皮交联（CXL）的安全性和有效性，然后与 UVA CXL 进行比较，与 FS 激光（NLO CXL）相比，在兔子中。
将 36 只兔子的上皮细胞加工成 2 乘以 25 微米的 MCs，MCs 密度为 400 MCs/mm2。用 1%核黄素（Rf）溶液处理眼睛 30 分钟，冲洗，然后用 UVA 或 NLO CXL 交联。通过上皮染色、光学相干断层扫描（OCT）成像和触觉测定监测兔子。在 2、4 或 8 周后处死，检查角膜胶原自发荧光和免疫组织化学。
与产生平均 23.89 ± 5.6 mm2 上皮缺损的 UVA CXL 相比，NLO CXL 显示无上皮损伤，上皮缺损在第 3 天愈合。UVA CXL 还导致角膜敏感性丧失，平均 0.83 ± 0.24 cm 力引起眨眼反应，持续 28 天，仍明显低于对照或 NLO CXL。OCT 成像仅在 UVA CXL 后检测到分界线，但不在 NLO CXL 后检测到。
即使 Rf 经上皮渗透得到改善，UVA CXL 仍会导致严重的上皮损伤、角膜敏感性丧失和持续一个月的延迟伤口愈合。然而，当 MCs 与 NLO CXL 结合使用时，这些问题大多被消除。这表明 MC NLO CXL 可以在没有术后疼痛或感染风险的情况下更快地恢复视力。
张锐
