多焦點圖型角膜手術視力矯正之光學模擬

隨現代科技的進步與用眼習慣的改變，眼睛老化(老花眼)提早發生等問題日漸嚴重。老花眼則是因為隨著年紀，眼睛中的水晶體組織產生的老化變硬失去彈性現象。近年來，雷射屈光矯正技術的快速發展，進行雷射矯正屈光不正的人也越來越多，利用雷射切削取代傳統的手術刀切割角膜皮瓣的方式，不但角膜皮瓣的厚度變薄且傷口變小，術後的恢復速度也較快。所謂的老花眼，是由於眼球內部組織老化造成水晶體彈性減弱、組織變硬而喪失原先的調節功能；正常水晶體視近時舒適程度大約需要5個屈光度，而老花眼患者水晶體調節能力只剩下1個屈光度左右。老花眼的患者對於近距離事物，因為調節能力的退化而無法看清。本研究透過光學模擬的方式，以多焦點同心圓環型波浪狀的角膜切削手術，在角膜上以雷射切削燒蝕出多焦點同心圓，藉此來改善水晶體調節能力不足的問題。透過ASAP模擬發現調節能力由原本的1個屈光度提升至4個屈光度，大幅的提升調節幅度範圍。並透過光學軟體模擬治療前後在視網膜上成像清晰度的比較，可發現透過此技術大幅改善老花眼看近不清的症狀。

關鍵字

老花眼；多焦點同心圓環型波浪狀；雷射屈光手術

並列摘要

With the rapid development of vision correction techniques, increasing numbers of people have undergone laser vision corrective surgery in recent years. The use of a laser scalpel instead of a traditional surgical knife reduces the size of the wound and quickens recovery after surgery. The primary objective of this article is to examine corneal surgery for vision correction via multi-layer swim-ring- shaped wave circles of the technique through optical simulations with the use of Monte-Carlo ray tracing method. Presbyopia stems from the loss of flexibility of crystalline lens due to aging of the eyeball. Diopter adjustment of a normal crystalline lens could reach 5D; in the case of presbyopia, the adjustment was approximately 1D, which made patients unable to see objects clearly in near distance. Corneal laser surgery with multi-layer swim-ring-shaped wave circles was performed, which ablated multiple circles on the cornea to improve flexibility of the crystalline lens. Simulation results showed that the ability of the crystalline lens to adjust increased tremendously from 1D to 4D. The method was also used to compare the images displayed on the retina before and after the treatment. The results clearly indicated a significant improvement in presbyopia symptoms with the use of this technique.

並列關鍵字

Presbyopia ； Multi-layer pattern ； Laser in situ keratomileusis

參考文獻

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國際替代計量

多焦點圖型角膜手術視力矯正之光學模擬

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