Phacoemulsification in Pseudo-exfoliation Syndrome скачать в хорошем качестве

Phacoemulsification in Pseudo-exfoliation Syndrome

Pseudoexfoliation syndrome (PXF) is an age-related systemic microfibrillopathy that targets ocular tissues through the gradual deposition of fibrillary residue from the lens and iris pigment epithelium, mainly on the lens capsule, ciliary body, zonules, corneal endothelium and iris. The diagnosis of PXF is aided by characteristic findings during the ophthalmic examination. Typically, white fibrillary residue on the anterior lens capsule and pupillary margin is observed, as are pupillary transillumination defects and pigmentation of the trabecular meshwork. PXF is a risk factor for glaucoma (most often open-angle) and has been correlated with an increased incidence of cataract formation. In PXF, the deposition of extracellular fibres results in predictable alterations of tissues of the anterior segment, making cataract operations potentially challenging. Surgeons must be aware of numerous intraoperative and post-operative issues in managing patients with PXF. Two pathological manifestations of PXF, zonular weakness and poor pupillary dilation, have been identified as the most significant risk factors for surgical complications. Zonular weakness can be attributed to the deposition of pseudoexfoliative material on the zonular fibres and ciliary processes, resulting in a proteolytic disintegration of the zonule that can lead to spontaneous fragmentation. Poor pupillary dilation results from infiltration of the iris stroma with the excessive extracellular matrix, causing mechanical obstruction during mydriasis. PXF can present some unique obstacles to successful phacoemulsification. Nonetheless, with appropriate preparation and adjunctive devices, phacoemulsification is still the preferred method of cataract extraction in this patient population.