The anterior chamber (AC) and posterior chamber (PC) of the eye are connected through the pupil and are filled with aqueous humour. The aqueous flows from the posterior to the AC at an approximately constant rate, and the intraocular pressure is governed by this rate and the resistance to aqueous outflow. In some patients the iris and lens come into contact, leading to pressure build-up in the PC, peripheral axial shallowing of the AC and, possibly, to angle-closure glaucoma. This can lead to blindness, which may be prevented by surgically creating an iridotomy, that is a hole through the iris to facilitate the flow from the posterior to the AC. The problem of optimal size and location of an iridotomy is still poorly understood. In this article, we study aqueous flow in the PC and investigate how it is modified in the presence of an iridotomy. Our approach is based on the lubrication theory, which allows us to solve the problem semi-analytically. We treat the iridotomy as a point sink and assume that the flux through it is proportional to the pressure. We find that the ideal size and location of an iridotomy are influenced by various geometrical and fluid mechanical factors, the most relevant of which are the size of the hole and the length and height of the iris-lens channel. For certain iridotomy diameters, we find that the jet velocity through the iridotomy might be large enough to cause possible corneal damage.

中文翻译：

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眼后房的房水流动及其由于瞳孔阻滞和虹膜切开术而引起的改变。

眼睛的前房（AC）和后房（PC）通过瞳孔相连，并充满房水。房水以大致恒定的速率从后部流向AC，并且眼内压受该速率和对房水流出的阻力的控制。在某些患者中，虹膜和晶状体接触，导致PC中压力升高，AC周围轴向变浅，并可能导致闭角型青光眼。这可能导致失明，这可以通过手术创建虹膜切开术来预防，即通过虹膜的一个孔以促进从后眼到AC的流动。虹膜切开术的最佳尺寸和位置的问题仍然知之甚少。在本文中，我们研究了PC中的水流，并研究了在虹膜切开术存在的情况下如何对其进行修改。我们的方法基于润滑理论，这使我们可以半解析地解决问题。我们将虹膜切开术视为点沉，并假设通过它的流量与压力成正比。我们发现，虹膜切开术的理想尺寸和位置受各种几何和流体力学因素的影响，其中最相关的是孔的大小以及虹膜透镜通道的长度和高度。对于某些虹膜切开术直径，我们发现通过虹膜切开术的射流速度可能足够大，以致可能造成角膜损伤。我们发现虹膜切开术的理想尺寸和位置受各种几何和流体力学因素的影响，其中最相关的是孔的大小以及虹膜透镜通道的长度和高度。对于某些虹膜切开术直径，我们发现通过虹膜切开术的射流速度可能足够大，以致可能造成角膜损伤。我们发现，虹膜切开术的理想尺寸和位置受各种几何和流体力学因素的影响，其中最相关的是孔的大小以及虹膜透镜通道的长度和高度。对于某些虹膜切开术直径，我们发现通过虹膜切开术的射流速度可能足够大，以致可能造成角膜损伤。