2020–2021 BCSC Basic and Clinical Science Course™
11 Lens and Cataract
Chapter 12: Preparing for Cataract Surgery in Special Situations
Cataract Following Pars Plana Vitrectomy
Nuclear cataract formation is common after pars plana vitrectomy, especially in patients older than 50 years. The use of silicone oil during retinal surgery typically yields posterior subcapsular opacification. Posterior plaque may also be seen after pars plana vitrectomy. In the absence of a vitreous cushion, the posterior capsule becomes more mobile. Thus, careful attention to fluctuations in AC depth is important, to avoid a surge upon breaking vacuum when a piece of lens is aspirated (see Chapters 8 and 10). Lowering the irrigation bottle and decreasing the fluid flow rate prior to placing the phaco tip inside the eye are helpful. These maneuvers are also recommended when zonular integrity is altered as a result of prior retinal surgery or preexisting ocular disease. Note that overfilling the anterior chamber with OVDs can cause zonular stretch and breakage. Extra caution is also necessary to prevent pieces of the lens from being lost during hydrodissection in case an inadvertent capsular break had occurred during the retinal surgery. A large capsulorrhexis allows prolapse of the nucleus during hydrodissection for an iris-plane phaco chop. If the surgeon selects an extracapsular surgical technique instead of phacoemulsification, the absence of vitreous reduces posterior pressure to aid lens expression. Alternatively, after capsulorrhexis and hydrodissection of the nucleus from its cortical attachments, the nucleus can be removed using a lens loop or irrigating vectis. Patients who receive intravitreal injections also may have an inadvertent opening of the posterior capsule; these patients may be treated similarly to postvitrectomy patients (described previously).
Excerpted from BCSC 2020-2021 series: Section 11 - Lens and Cataract. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.