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        1. 近视能自愈吗?

          从现有的研讨成果看,近视是不能自愈。

          无论是转眼闪现、意念冥想、阳光浴眼,还是雾视疗法、按摩穴位、近视治疗仪.....

          都不能让已经近视的眼睛,自己痊愈,恢复如初。

          来说说原因。

          眼睛是一个生物器官,也是一个光学器官,它负责把外界视觉信息聚焦到视网膜上,再传输到大脑,大脑中枢再进行处置,然后被我们感知。

          当眼睛正常时,平行光线进入眼内,经过角膜、晶状体等折射,最终会在视网膜上聚焦形成清楚的图像。

          但如果近视了,平行光线进入眼内,并没有聚焦到视网膜上,而是聚焦到视网膜前面,导致视网膜上没法显示出清楚的图像。

          虽然,直到到今天,科学界对于人为什么会患上近视(基因遗传?环境因素?)还有争议。

          但是对为什么光线没法聚焦到视网膜上,而是聚焦到视网膜前,倒是有了共鸣。

          重要原因有二:

          • 一是患者的眼轴过长。
          • 二是患者的角膜和晶状体状况产生了转变。

          先说眼轴过长。

          假设眼睛是个光学仪器,那么从眼球接收光线的表层(角膜)到最里层(视网膜)之间的中轴线距离,叫做眼轴

          正常人的眼轴长度大约是 24 mm,也就是角膜到视网膜之间的距离是 24 mm。而光线经过角膜、晶状体等折射后聚焦成像的地位,距离角膜也是 24 mm。

          也就是说,视网膜和视觉信息折射后聚焦的地位重合,这样,视觉信息完善聚焦到视网膜上。

          而近视患者的眼轴要擅长 24 mm,换句话说,视觉信息经过折射后,聚焦到眼里的地位不变,但视网膜因为眼轴变长往后退了。于是乎视觉信息没法在视网膜上感光成像,也就一片含混。

          如果不好懂得,我画个图给你说明:

          正常人的眼睛。光线从 A 进入,成像在 B 处,A 是角膜,C 是视网膜。B 和 C 是重合的。于是 B 处的聚焦完善的显示在 C 处的视网膜上。

          但是近视患者。光线从 A 进入,因为眼轴过长,C 处的视网膜往后倒退了。然而入眼的视觉信息的聚焦还停留在 B 处,B 在 C 前面,视觉信息无法清楚聚焦到视网膜上,于是一片含混。

          也许有人会问,为啥眼睛没法调节进入的光线,对于眼轴过长的人,把成像往后聚焦下?

          幻想很饱满,现实很骨感。

          光线进入眼睛,要经过一系列庞杂的折射,这个进程受到角膜和晶状体状况的影响,不是可以主动调节的。

          也就是说 A 到 B 之间的距离大部分时光是恒定的。说是聚焦到 B 上,就不会乱跑,「乱跑」的是 C 处的视网膜。

          说到底,因为眼轴过长导致的近视,就是眼睛自己的长度产生了变更。常有人说,近视患者眼睛往外凸,这个凸就是眼睛变长的表示。

          眼睛变长,眼轴就变长,成像对不上,也就近视了。

          再说说角膜和晶状体状况产生了变更。

          光线进入眼睛,要经过庞杂地折射,然后聚焦到固定的地位上,影响这个折射的器官,重要是眼睛前部的角膜和晶状体。

          有些人他的眼轴长度是正常的。但是负责折射的角膜和晶状体的状况产生了变更,把底本该聚焦在视网膜上的成像,聚焦到了视网膜前面。

          就像下图这样:

          A 是角膜和晶状体等器官,C 还是视网膜,底本光线经过 A 处的折射会直接聚焦到 C 上,但是因为角膜和晶状体状况呈现异常,折射的光往前聚焦到了 D 上。

          这个 D 成了真实的聚焦点,然而 D 还是在 C 前面,于是乎,就近视了。

          上面之所以说那么多,只想告知你,人之所以视觉正常,是因为进入眼睛的视觉信息聚焦地位和视网膜完善重合。而近视患者:

          • 大部分是因为眼轴过长,进入的视觉信息聚焦地位不变,而视网膜却往后退,聚焦地位在视网膜前面。
          • 少部分是因为角膜和晶状体的状况产生了变更,视网膜地位不变,但是折射聚焦的地位却提前了,聚焦地位还是在视网膜前面。

          想要让近视自愈,就要看过长的眼轴,能不能主动的恢复正常。或者折射出错的角膜和晶状体状况,能不能主动恢复正常。

          然而,很遗憾。

          现在的研讨成果显示,人的眼轴过长是个不可逆的进程,只要变长,就不会主动变回去。

          同样,角膜和晶状体的状况,也一样,只要产生了转变,除非是佩戴角膜塑形镜,或者一些生理性的老化,否则也不会主动变回去。

          角膜塑形镜是可以通过转变角膜的状况从而到达近视不用戴镜的后果,但这算是一种医学手腕,自然算不得是自愈。

          除此之外无论你是按摩,还是热敷,还是眺望远方,还是经常眨眼,还是放空冥想,还是什么视力训练恢复法。

          都无法通过这些按按揉揉捏捏动动眼球的方法,让变长的眼轴变短,让角膜和晶状体的状况产生转变。

          丁丁医生,那为啥一些近视按摩方式宣称,按摩后测试确切视力变好了呢?

          有两个原因。

          一. 患者是假性近视而不是真的近视。

          影响光线进入眼睛折射,重要看角膜和晶状体的状况,而晶状体的状况,重要靠睫状肌来调节。

          当眼睛长时光看近,睫状肌就一直处于压缩工作的状况,就有可能会引起疲劳痉挛,晶状体的状况产生暂时性的转变,影响了对入目光线的折射。这种睫状肌疲劳的状况就是假性近视。

          假性近视和近视的症状很像。但说到底,患者的一没有眼轴变长,二晶状体只是暂时性的状况转变。所以通过按摩放松,调节用眼方法,视力是会恢复正常的。

          究竟这个近视是「假的」,这种按摩自愈自然算不上是近视的自愈。

          二. 故意混杂概念。

          很多宣称可以按摩自愈近视的机构都爱好用视力测试的手腕来证明自己方式多么有效。

          但实际上用视力来断定近视的治疗后果本身就不客观。

          比如很多机构宣称可以训练睫状肌的调节才能,从而下降度数,但是眼睛真实的屈光度数,本身就应当是去掉了调节,检讨出来的才是正确的度数。

          还有一些会把屈光度数和裸眼视力混为一谈,按摩训练停止后,也不散瞳验光查度数,只是查下裸眼视力,然后就说视力进步,近视治好。其实基本不是一回事。裸眼视力有进步,并不代表你的真实度数降落。

          这也是为什么我在

          配眼镜,如何挑选眼镜框和镜片?有哪些常识或技能? - 知乎

          这个答复里提到的。

          验光须要去正规的医院眼科,在那里才干区分真假近视,才干验出真实的近视状态。

          如果你真的近视了,无论是眼轴变长,还是角膜晶状体状况转变,想看得清世界的花花草草,配戴眼镜是最简略的方式。

          角膜塑形镜是可以通过转变角膜的状况到达近视不用戴镜的后果,近视改正手术也能让近视患者摘下眼镜。

          但是大部分人所懂得的那种按摩、眺望、动眼、或者近视治疗仪之类的近视自愈方式,都是无效的。

          丁香医生知道你们非常想懂得角膜塑形镜和近视改正术的相干问题。

          这个,我们下次再说。

          内容参考丁香医生科普文章:

          近视通过锤炼可以自愈吗?

          作者:游玉霞 北京同仁医院验光中心 视光医师

          知乎 ID:YOYO游 - 知乎

          ▲关注它,「育On the 8th of May, 1777, Ministers moved for more money for the insatiable Landgrave of Hesse, whose troops were at this very time exhibiting the most scandalous state of defiance of discipline, of consequent inefficiency, and of plunder of the inhabitants of America. This grant, though violently opposed, was carried, but only by a majority of eight. All parties now began to denounce the shameless rapacity of these German princes. Nor did Chatham, ill as he was, allow the Session to pass without making one more energetic protest against the continuance of the war with America. On the 30th of May he moved an address to his Majesty for the immediate cessation of hostilities. Notwithstanding all that had been said on our successes over the Americans, Chatham contended as positively as ever that we could never conquer them. "You have," he said, "ransacked every corner of Lower Saxony, but forty thousand German boors never can conquer ten times the number of British freemen. You may ravage, you cannot conquer—it is impossible—you cannot conquer America. You talk of your numerous funds to annihilate the Congress, and your powerful forces to disperse their army; I might as well talk of driving them before me with my crutch! But what would you conquer? The map of America? I am ready to meet any general officer on the subject" (looking at Lord Amherst)—"What will you do out of the protection of your fleet? In the winter, if together, they are starved; and if dispersed, they are taken off in detail. I am experienced in spring hopes and vernal promises. I know what Ministers throw out; but at last will come your equinoctial disappointment. You have got nothing in America but stations. You have been three years teaching them the art of war. They are apt scholars; and I will venture to tell your lordships that the American gentry will make officers enough fit to command the troops of all the European Powers." Chatham's motion was rejected by ninety-nine votes against twenty-eight. Parliament was prorogued by the king on the 6th of June, in a speech in which he indulged the fallacious hope that the American insurrection would be terminated in the present campaign. But Chatham's prophecies were at the very time realising themselves. Had the Howes had the necessary qualities of commanders in such an important cause—had they pursued and dispersed[235] the American army, as they ought to have done on defeating it, and as they might readily have done; and had the British Government instantly, whilst in this favourable position, repealed all the obnoxious statutes, they would have thrown Congress and Washington so completely into the wrong, that it would have been impossible for them to have made head again. But neither the Generals nor the Government of that day had the capacity for such strategic and statesmanlike policy. The Generals went comfortably into winter quarters, leaving the embers of war to rekindle and spread; and Government, deaf to the warnings of Chatham, still stolidly refused justice whilst rigorously enforcing their injustice. And, indeed, when Chatham gave his last Cassandra-like remonstrance, it was already too late. We had indeed taught the Americans the art of war. Washington was no longer contented to stand on the defensive, happy if he could preserve his soldiers from running off without fighting at all. His circumstances were desperate, and the energy which springs from despair now urged him to measures of daring and wakefulness just as the English Generals, like northern bears, were entering on their winter's sleep. Benedict Arnold had paid him a visit in his wretched camp beyond the Delaware, and probably from their united counsels sprang a new style of movement, which confounded his unsuspecting enemies.儿知识大礼包」免费拿~原价169元,只需2步,0元领走!