[Endocapsular Cataract Surgery Using the Excimer Laser at 308 Nm].

We present our experience with in vitro endocapsular cataract surgery ("phakoablation") using the excimer laser at a wavelength of 308 nm. The ablation threshold for human lens nuclei (0.5 J/cm2) was found to be significantly lower compared to that for the capsule (1.5 J/cm2). A total energy of 215 J (mean value) is required for endocapsular ablation of human lens nuclei. For cataract surgery the laser pulses are coupled to a quartz fiber that is integrated into an irrigation/aspiration handpiece. Using the prototype we developed, endocapsular cataract surgery on autopsy eyes with opaque lenses could be performed within about 30 min without major damage to the capsule. Initial measurements of retinal UV exposure indicate that retinal damage might be expected only if the posterior lens capsule is ruptured. Thus endocapsular cataract surgery with the excimer laser seems to be feasible.