Experimental choroidal surgery for age-related macular degeneration

黄斑变性是英国最常见的致盲原因，大多数人都有一个老年亲属在某种程度上受到这种疾病的影响。黄斑变性会导致视觉中心部分的燃烧，使患者无法阅读或识别人？的脸。视网膜是由一个薄而脆弱的感觉层组成的，它很容易被一个更坚固的被称为脉络膜的层破坏、内衬和保护。这类似于轮胎内的内胎。黄斑变性开始于脉络膜（轮胎）层，但在一段时间内逐渐侵蚀通过损害视网膜（内胎），在这一点上的视力丧失。我们研究的目的是开发一种手术，在中央视网膜受到不可逆的损伤之前，将退化的脉络膜从中央视网膜上移开。我们建议通过旋转脉络膜层的一个大碟后，解除了视网膜。这将使患病的脉络膜从中央凹（视网膜的敏感中心部分）移动到周边视网膜的另一部分，在那里视力丧失几乎不明显。因此，中央凹将具有相对健康的脉络膜，这可以使退化倒退数十年。手术是从眼睛内部进行的，非常具有挑战性，但最近开发的仪器使其变得更容易。我们已经在我们医院的患者中完成了一项试验，并表明这项技术原则上运作良好。然而，我们发现，我们需要滑动一个更大的脉络膜层，并以这样一种方式，保留下面的血管。我们已经设计了一种方法来做到这一点，但手术与我们以前做过的任何手术都大不相同，因此我们需要在进行另一项临床试验之前在动物模型中验证其效果。从伦理上讲，我们必须确保在向患者推荐手术之前没有意外的问题。

Age-related macular degeneration is the commonest cause of blindness in the UK and most people have an elderly relative who is affected by the disease to some extent. Macular degeneration leads to a burning out of the central part of the vision, leaving patients unable to read or recognise people?s faces. The retina is made up of a thin delicate sensory layer that is easily damaged, lined and protected by a more robust layer known as the choroid. This is analogous to an inner tube inside a tyre. Macular degeneration begins in the choroid (tyre) layer, but over a period of years gradually erodes through to damage the retina (inner tube), at which point vision is lost. The aim of our research is to develop an operation to move the degenerating choroid away from the central retina before it is irreversibly damaged. We propose to do this by rotating a large disc of the choroid layer after lifting up the retina. This will move the diseased choroid away from the fovea (the sensitive central part of the retina) to another part in the peripheral retina where vision loss will be barely noticeable. The fovea will thus be provided with relatively healthy choroid, which may set the degeneration back many decades. The surgery is performed from within the eye and is extremely challenging, but instruments developed recently have made it easier. We have already completed one trial with patients in our hospital and showed that this technique works well in principle. We have however discovered that we need to slide a much larger choroid layer and in such a way that preserves a blood vessel underneath. We have devised a means of doing this, but the surgery is quite different to anything we have done before and we therefore need to validate its effects in an animal model before proceeding to another clinical trial. Ethically we must be sure that there are no unexpected problems with the surgery before recommending it to our patients.