電子眼研究有新的突破,，使失明人士有可能重見光明。南加州大學(xué)Doheny眼科研究所的研究人員在視網(wǎng)膜色素變性（ Retinitis Pigmentosa ）患者的視網(wǎng)膜植入人造視網(wǎng)膜,，讓他們感應(yīng)到光和分辨對象,，若進(jìn)一步測試取得成功，人造視網(wǎng)膜植入系統(tǒng)將于兩年內(nèi)推出市場,，造福全球數(shù)以百萬名患者,。
這項裝置第一代已經(jīng)于2002年進(jìn)行臨床實驗。第一代人造視網(wǎng)膜植入六名病人的視網(wǎng)膜上,。這些病人患有視網(wǎng)膜色素變性,，這是一種無法可治的退化病，每三千五百人中有一人罹患此癥,。研究人員原本預(yù)計他們植入人造視網(wǎng)膜后只能看見光,，想不到效果更為理想,，可看見大型字母,，分辨杯、刀和碟等物體,，而且看得見動作,。
新儀器名為「 Argus II 人造視網(wǎng)膜系統(tǒng)」，美國當(dāng)局最近批準(zhǔn)南加州大學(xué)對五十至七十五名眼疾病人進(jìn)行臨床測試,。該校多希尼眼科學(xué)院的眼科學(xué)授Mark Humayun表示,，若研究進(jìn)度理想，這個電子眼儀器將于2009年初推出市面,。
將進(jìn)行測試的第二代人造視網(wǎng)膜將提供更佳視力,，它有六十個感光電極，遠(yuǎn)較之前的十六個為多,。Humayun預(yù)測,，未來五至七年內(nèi)人造視網(wǎng)膜將有更大進(jìn)展,，電極數(shù)目達(dá)千個，可讓失明人士能夠辨認(rèn)面孔,。研究人員的最終目標(biāo)是讓人們可以辨認(rèn)面孔,，讓完全失明的人可以照顧自己。
(資料來源 : Bio.com)
英文原文：
03/21/07 -- Patients who have gone blind are a step closer to perhaps one day regaining some of their sight. Researchers at the University of Southern California (USC), Doheny Eye Institute, announced today the next step in their efforts to advance technology that will hopefully help patients with retinitis pigmentosa and macular degeneration regain some vision using an implanted artificial retina.
The announcement by Mark Humayun, M.D., Ph.D., professor of ophthalmology at the Doheny Eye Institute, Keck School of Medicine of USC came at a press conference at the American Association for the Advancement of Science (AAAS) annual meeting in San Francisco.
The Food and Drug Administration (FDA) recently approved an Investigational Device Exemption (IDE) to conduct a clinical study of the new device- dubbed the Argus II Retinal Prosthesis System.
The implantable technology is a collaborative effort between USC and Second Sight Medical Products, which manufactures the implant. The Argus II is the second generation of an electronic retinal implant designed for the treatment of blindness due to retinitis pigmentosa (RP), a group of inherited eye diseases that affect the retina. RP causes the degeneration of photoreceptor cells in the retina, which capture and process light helping individuals to see. As these cells degenerate, patients experience progressive vision loss. The Argus device is essentially designed to take the place of the photoreceptors.
"The first phase of our implant work began in 2002," says Humayun. "We have successfully implanted six patients in the trial and we have found that the devices are indeed electrically conducting and can be used by patients to detect light or even to distinguish between objects such as a cup or plate."
While the first generation of implants contained 16 electrodes laid out on an array, the Argus II is designed with 60 electrodes, which is intended to allow for higher resolution images.
The new device is also approximately one quarter the size of the original, reducing surgery and recovery times.
The array is attached to the retina and used in conjunction with an external camera and video processing system to provide a rudimentary form of sight to implanted subjects.
The clinical trial of the first generation of implants continues at the Doheny Eye Institute at USC. All six previously blind patients in the first trial have been able to detect light, identify objects in their environment and even perceive motion after implantation with the first generation device.
The device, ultimately, may be used for the millions of people suffering from age-related macular degeneration, or AMD. In fact, Humayun says, there are 25 million people around the world, including 6 million in the United States alone, who have been blinded, or are severely visually impaired, due to diseases like RP and AMD.
By 2020, that figure is expected to double, creating a virtual vision-loss epidemic.
Both AMD and RP destroy vision by annihilating the retinal cells that allow light to be translated into recognizable images.
"Perhaps what we're most excited about in this next study," says Humayun, "is, similar to the first generation Second Sight device, we will be able to test the new device with patients at their homes, churches, schools and similar locations. The importance of this work is going to be reflected in how well this helps them regain some of their lost vision."
The current study will include patients over 50 years of age who have RP or AMD and who have had previous functional vision.
Source: University of Southern California
