敢试试吗？20秒激光手术给你蓝眼睛

For the majority of us, blue eyes have been attainable only with the aid of colored contact lenses or artificial iris implants. But that will soon change with the introduction of a new medical procedure pioneered by California company Stroma Medical that can turn brown eyes blue.

The laser procedure works by eliminating the melanin from the surface of the iris, which then allows light to enter and scatter in the stroma. The effect is similar to Rayleigh scattering, in which wavelengths of sunlight hit much smaller molecules in the air and then scatter, which makes the atmosphere appear blue.

“The fundamental principle is that under every brown eye is a blue eye,” Dr. Gregg Homer told CNN, adding that there is no actual blue pigmentation in the eye. “The only difference between a brown eye and a blue eye is this very thin layer of pigment on the surface.

“If you take that pigment away, then the light can enter the stroma — the little fibers that look like bicycle spokes in a light eye – and when the light scatters it only reflects back the shortest wavelengths, and that’s the blue end of the spectrum.”

The laser treatment disrupts the fragile layer of pigment on the iris, which causes the body to start removing the tissue naturally. While the procedure itself only takes around 20 seconds, the blue eyes do not emerge for several weeks, as the body can only gradually release the pigment.

Stroma Medical has yet to gain approval from the regulatory bodies in the United States. The company’s medical board has stated that preliminary studies show that the surgery is safe, but so far only 37 patients have undergone the treatment — including 17 patients in Mexico and another 20 in Costa Rica. Currently, the price to change brown eyes blue stands at a hefty US$5,000.

The medical industry, ophthalmologists in particular, has not been particularly receptive to the procedure. The skepticism is based on the fact that eyes are one of the most sensitive organs in the human body, and that the procedure is irreversible.Words to Learn

相关词汇

【基质】jīzhì

stroma the tissue forming the ground substance, framework, or matrix of an organ

【色素】sèsù

pigment any coloring matter of the body

对大多数人而言，蓝色眼睛只能靠佩戴有色隐形眼镜或植入人工虹膜来实现。不过，这一切很快就要改变了。美国加州基质医学公司率先引进的一项新手术可以让棕色眼睛变成蓝色。

这项激光手术通过消除虹膜表面的黑色素，让光线得以进入虹膜，分散在基质层上，从而让眼睛呈现出蓝色。这一过程和瑞利散射的原理类似，当阳光的波长触及空气中的分子散射开来，天空就会呈现蓝色。

格雷格•荷马医生告诉CNN说：“基本原理是，每只棕色眼睛的后面都是一只蓝色眼睛。”他补充说，其实眼睛里并没有蓝色的色素。棕色眼睛和蓝色眼睛的唯一区别就在于虹膜表面的这层极薄的色素。“如果你把这层色素移去，光线就可以进入到基质层 —— 这层纤维肌在浅色眼睛中看起来就像自行车辐条 —— 当光线分散到基质层

上，只有波长最短的光线会反射回去，也就是光谱中的蓝光。”

激光手术会破坏虹膜表面这层脆弱的色素，促使人体自然地移除相关组织。尽管手术本身只需20秒钟，但是要过上数周，眼睛才能变成蓝色，因为人体只能逐渐地释放色素。

基质医学公司尚未获得美国监管机构的许可。该公司的医务委员会声称，前期研究显示，手术是安全的，但到目前为止总共只有37位患者接受了这种手术。17位患者在墨西哥，其余20位在哥斯达黎加。当前把棕色眼睛变成蓝色眼睛的手术费用较高，需5000美元。

医疗界尤其是眼科医生对这种手术的接受度不是特别高。他们质疑的依据是，眼睛是人体最敏感的器官之一，而这种手术是不可逆的。(Chinadaily.com.cn)