Name: 眼睛雷射手術是怎麼運作的？ (How does laser eye surgery work? - Dan Reinstein)
Uploaded: 2020-01-06T21:01:20.000Z
Duration: 5 min 37 s

In 1948, Spanish ophthalmologist Jose Ignacio Barraquer Moner was fed up with glasses.

1948 年，西班牙眼科醫生荷西伊納西歐 · 巴拉凱爾莫尼爾受夠了眼鏡。

關係子句

He wanted a solution for blurry vision that fixed the eye itself, without relying on external aids.

他希望能找到以修復眼睛本身的辦法來解決視力模糊的問題，不要再仰賴外部的協助。

But the surgery he eventually devised was not for the faint of heart.

但，他最終設計出來的手術完全不適合膽小的人。

Barraquer began by slicing off the front of a patient's cornea and dunking it in liquid nitrogen.

巴拉凱爾一開始先把病人的角膜前側切下來，把它泡在液態氮中。

Using a miniature lathe, he ground the frozen cornea into the precise shape necessary to focus the patient's vision.

他用一個迷你車床， 將冰凍的角膜磨成能夠讓病人視力聚焦的精確形狀。

Then he thawed the disc, and sewed it back on.

接著，他把這個圓盤解凍後再縫回去。

Barraquer called this procedure keratomileusis, from the Greek words for "carving" and "cornea."

巴拉凱爾把這種手術稱為「角膜重塑術」，是用希臘字「切刻」和「角膜」組成的。

And though it might sound grisly, his technique produced reliable results.

雖然他的技術聽起來很可怕，結果卻很可靠。

所以，巴拉凱爾的手術是怎麼一回事？

Keratomileusis corrects what are called refractive errors: imperfections in the way the eye focuses incoming light.

角膜重塑術會修正所謂的折射錯誤：眼睛無法完美地將射入的光線進行對焦。

Ideally, the cornea and lens work together to focus light on the surface of the retina, but several kinds of refractive errors can impair this delicate system.

理想上，角膜和晶體會合作將光線聚焦在視網膜表面上，但好幾種折射錯誤都可能妨礙這個脆弱的系統。

In people with myopia, or short-sightedness, a steep cornea focuses light just short of the retina.

就有近視眼的人來說，比較陡的角膜會讓光線的聚焦點無法抵達視網膜。

Those with hyperopia, or far-sightedness, have the opposite problem:

Light is focused too far beyond the retina.

光線被聚焦的點遠超過了視網膜。

And in people with astigmatism, the cornea has two different curvatures which focus light at two distances and produce blurry vision.

至於亂視的人，角膜則有兩種不同的曲度，會造成兩種光線聚焦的距離，導致視力模糊。

Even those with perfect vision will eventually suffer from presbyopia, or "aging eyes."

即使視力完美的人，將來也會有老花眼，即眼睛老化。

As the proteins in the lens age, they slowly increase its size.

水晶體內的蛋白質老化之後，會慢慢變大。

By an adult's mid-40s, the lens is too large to easily change shape and shift focus.

成人到了四十五歲左右，水晶體就會太大，無法輕易改變形狀和轉換焦點。

Glasses and contact lenses bend light to compensate for these refractive errors.

眼鏡和隱形眼鏡會改變光線方向來補償這些折射錯誤。

But, as Barraquer's procedure shows, we can also alter the shape of the cornea itself; moving the focal point backwards, forwards, or pulling a divided image together.

但，巴拉凱爾的手術證明，我們也能改變角膜本身的形狀；將焦點向前或向後移動，或者將分開的影像拉疊回來。

And thankfully, modern eye surgeons can sculpt the cornea with far less invasive tools.

謝天謝地，現代的眼睛外科醫生不需要用這麼入侵性的工具就可以雕塑角膜。

In corrective laser eye surgery, surgeons rely on excimer lasers.

做雷射眼睛矯正手術時，外科醫生要仰賴準分子雷射。

These tools are accurate enough to etch words into a human hair.

這些工具精確到能在人類頭髮上刻字。

To safely accomplish these ultra-fine incisions, they use a technique called photoablation.

為了要能安全完成這些極細緻的切割，他們會用一種叫做光剝離的技術。

This allows the lasers to essentially evaporate organic tissue without overheating surrounding eye tissue.

基本上，這種技術讓雷射能夠將有機組織蒸發，且不會讓周圍的眼睛組織過熱。

So how does laser eye surgery  actually work?

所以，眼睛雷射手術是怎麼做的？

The first step is to separate a thin layer from the front of the cornea.

第一步是從角膜前側分離出薄薄的一層。

This can be done with either a flat, wide blade, or a femto-second laser that produces millions of tiny plasma bubbles to create a plane beneath the corneal surface.

要做到這一點，可以使用平寬的刀片，或者飛秒雷射，它可以產生出數百萬個微小的電漿泡，在角膜表面底下創造出一個平面。

Surgeons then lift the flap to expose the inside of the cornea.

接著，外科醫生會將這蓋層掀起，露出角膜的內部。

Guided by the refractive error and the  shape of the cornea, the excimer laser robotically sculpts the exposed corneal bed into the correct shape.

根據折射錯誤及角膜的形狀來計算，準分子雷射會機械式地雕塑出露出來的角膜床，雕成正確的形狀。

This process usually takes less than 30 seconds for each eye.

這個過程通常每隻眼睛只要花不到三十秒的時間。

Finally, the flap is closed, and its edges reseal themselves in just a few hours.

最後，再將蓋層闔上，幾個小時內，它的邊緣會自行重新封上。

Because the lasering is done on the eyeball itself, it's described as "in situ," or "on site."

因為雷射手術是在眼球上進行，這手術會被描述為是「原位」的。

Its complete name is "laser in-situ keratomileusis," but you probably know it as LASIK.

它的全名叫做「準分子雷射原位層狀角膜塑形術」，但大家比較熟的可能是它的縮寫 LASIK。

Essentially, this technique carves a patient's contact lens prescription onto their cornea.

基本上，這種技術是將病人的隱形眼鏡處方直接刻在他們的角膜上。

Like any surgical procedure, LASIK comes with certain risks.

和任何外科手術一樣， LASIK 也會有風險。

Some patients experience slightly blurred vision that can't be corrected by glasses.

有些病人會發生輕微的視線模糊，且無法用眼鏡校正。

But the technique is currently about as likely to damage your eyes as wearing daily disposable contact lenses for one year.

但目前這項技術對眼睛的損害差不多等同於配戴拋棄式隱形眼鏡一年。

Today, a technique called SMILE enables surgeons to sculpt the cornea through even smaller incisions – further reducing recovery time.

現今，外科醫生會用一種叫 SMILE 的技術來雕塑角膜，手術的切口會更小，讓恢復時間更短。

And lasers aren't just correcting the three types of refractive errors. This technology can also restore aging eyes.

而且，雷射不僅能修正三種折射錯誤—— 這項技術也能恢復老化的眼睛。

In a technique called Laser Blended Vision, surgeons adjust one eye to be slightly better at distance vision and the other to be better at close range vision.

有一種叫雷射融合校視的技術，外科醫生能用它來做微調，讓一隻眼睛的遠距離視線更好，另一隻眼睛則是近距離視線更好。

The difference between the two eyes is small enough that most patients can merge their vision, allowing both eyes to work together at all distances.

兩眼之間的差距小到讓大部分的病人可以合併他們的視線，讓雙眼一起看各種不同的距離。

Advances in laser technology continue to make vision correction surgery more effective and accessible.

雷射技術的持續進步，讓視力矯正手術變得越來越有效，也越容易接受治療。

One day soon, Barraquer's vision of a world without glasses may finally come true.

在不久的將來，可能就能實現巴拉凱爾的遠景，一個沒有眼鏡的世界。