Exfoliation Syndrome

Abstract

Exfoliation syndrome (XFS) is an age-related disease in which abnormal fibrillar extracellular material is produced and accumulates in many ocular tissues. Its ocular manifestations involve all of the structures of the anterior segment, as well as conjunctiva and orbital structures. Glaucoma occurs more commonly in eyes with XFS than in those without it; in fact, XFS has recently been recognized as the most common identifiable cause of glaucoma. Patients with XFS are also predisposed to develop angle-closure glaucoma, and glaucoma in XFS has a more serious clinical course and worse prognosis than primary open-angle glaucoma. There is increasing evidence for an etiological association of XFS with cataract formation, and possibly with retinal vein occlusion. XFS is now suspected to be a systemic disorder and has been associated preliminarily with transient ischemic attacks, stroke, systemic hypertension, and myocardial infarction. Further ramifications await discovery. Deposits of white material on the anterior lens surface are the most consistent and important diagnostic feature of XFS. The classic pattern consists of three distinct zones that become visible when the pupil is fully dilated. Whereas the classic picture of manifest XFS has been often described, the early stages of beginning exfoliation have not been well defined. Next to the lens, exfoliation material is most prominent at the pupillary border. Pigment loss from the iris sphincter region and its deposition on anterior chamber structures is a hallmark of XFS. Despite extensive research, the exact chemical composition of exfoliation material (XFM) remains unknown. An overproduction and abnormal metabolism of glycosaminoglycans have been suggested as one of the key changes in XFS. The protein components of XFM include both noncollagenous basement membrane components and epitopes of the elastic fiber system such as fibrillium. Regardless of etiology, typical exfoliation fibers have been demonstrated electron microscopically in close association with the pre-equatorial lens epithelium, the nonpigmented ciliary epithelium, the iris pigment epithelium, the corneal endothelium, the trabecular endothelium, and with almost all cell types of the iris stroma, such as fibrocytes, melanocytes, vascular endothelial cells, pericytes, and smooth muscle cells. The presence of XFS should alert the physician to the increased risks of intraocular surgery, most commonly zonular dehiscence, capsular rupture, and vitreous loss during cataract extraction. Heightened awareness of this condition and its associated clinical signs are important in the detection and management of glaucoma, and preoperative determination of those patients at increased risk for surgical complications.

Genome-wide association study with DNA pooling identifies variants at CNTNAP2 associated with pseudoexfoliation syndrome

“…Whitish fibrillogranular material is visible by slit-lamp microscopy on the anterior lens capsule and at the pupillary border. 2 Furthermore PEX is one of the most common causes of open-angle glaucoma accounting for about 25% of all open-angle glaucoma worldwide. 2 The etiology of PEX syndrome is still poorly understood but increased prevalence of the disease in certain populations and observed familial aggregation are compatible with PEX being a complex genetic disorder.…”

Pseudoexfoliation - A Dreaded Nightmare in Cataract Surgery

“…IOL decentration has also been reported even when the lens is entirely in the capsular bag, primarily due to decentration of the entire bag. [19], [20] In our series 1 case had decentration due to zonular dialysis where CTR was not put and a 3 piece IOL was put in the bag. This study demonstrated an increased incidence of intraoperative and post-operative complications.…”

Current Diagnosis and Management of Angle-Closure Glaucoma

“…Marfan's syndrome), trauma or even pseudoexfoliation, can also predispose to angle-closure in a previously deep anterior chamber. (Ritch & Schlötzer-Schrehardt, 2001;Dureau, 2008). Secondary causes of angle-closure, such as phacomorphic, uveitic and neovascular cases, need to be promptly identified in order to establish a specific treatment.…”

“…(George et al, 2003;Thomas et al, 2004) Some zonular diseases may be related to secondary angle-closure glaucomas, such as exfoliation syndrome, Marfan´s Syndrome and Weil-Marchesani Syndrome, among others. (Ritch & Schlötzer-Schrehardt, 2001;Dureau, 2008) 7.3 Genetic and other external factors Similarities in ocular biometry in first-degree relatives of angle-closure patients, indicates that angle-closure related anatomical characteristics are at least partially heritable. The risk of developing angle-closure glaucoma was reported to be 3.5 times higher in first degree relatives of affected Inuit patients.…”