[Posterior YAG capsulotomy: selection of the application pattern].

Abstract

Background: The posterior neodymium-yttrium-aluminum-garnet laser capsulotomy is an established and simple method with a low complication rate for the treatment of secondary cataracts; however, the risk of intraocular pressure elevation, pit marks of the intraocular lens (IOL), anterior hyaloid damage, cystoid macular edema and retinal detachment may increase with high pulse number, pulse energy, and total energy.

Purpose: The optimization potential of the method through a rational choice of the laser pattern and the strategy, taking into account the mechanical properties of the posterior capsule and the anatomical features of the retrolental region, is shown.

Material and methods: The article provides a literature review with own clinical observations and a geometric representation.

Results: The efficiency of a laser pattern is examined with a constant capsulotomy length: The largest opening can be reached with the U‑pattern, which is followed by the +, T, H, V, O and spiral patterns in decreasing order. When estimating the size of the opening, its incircle is of particular functional importance. If the ability of the posterior capsule to tear spontaneously, which is predetermined by its anatomical and mechanical properties, is taken into account when choosing the application pattern and the laser strategy, the efficiency of the method increases.

Conclusion: An efficient technique is not only determined by an adapted defocusing and a minimum possible individual pulse energy setting but also characterized by the lowest possible total energy consumption if the necessary opening size is achieved by the smallest number of pulses. Taking into account the individual retrolental anatomical conditions and the mechanical properties of the NS membrane can contribute to the gentle implementation of a YAG capsulotomy.