Owing to the use of wide-angle observation systems1,2 the lens can be preserved during the vast majority of pars plana vitrectomies. When such lenses later develop cataracts, they frequently exhibit nuclear sclerosis of such a degree that phacoemulsification would no longer be a safe procedure, even for experienced anterior-segment surgeons who are more and more comfortable emulsifying denser and denser lenses. The vitreous cavity of these eyes is filled with aqueous or silicone oil. This fact renders standard extracapsular cataract extraction with expression of the lens nucleus potentially hazardous because pressure on the globe may lead to collapse of the posterior segment in eyes filled with aqueous or to a localized rupture of the zonule and subsequent formation of a persistent pathway through which silicone oil can pass from the vitreous cavity into the anterior chamber.
To avoid such complications, extracapsular cryoextraction, followed by an irrigation-aspiration procedure, has proven
Spitznas M. Extracapsular Cryoextraction and Irrigation-Aspiration Procedure for Removal of Nuclear Sclerotic Lenses From Vitrectomized Eyes. Arch Ophthalmol. 1993;111(7):900. doi:10.1001/archopht.1993.01090070018003