Floaters become more prevalent with age because of degenerative vitreous changes that occur throughout life. In youth, hyaluronan keeps collagen fibrils separated in the vitreous cavity and thus maintains transparency of the vitreous. However, with time, hyaluronan dissociates from collagen, causing cross-linking and aggregation of collagen with fibrous structures that scatter light—a process known as vitreous liquefaction.1-3
Clinically, a posterior vitreous detachment (PVD) is often marked by a degree of fibroglial tissue known as a Weiss ring that is free floating over the optic nerve. A PVD allows the vitreous body to move when the head or eye moves, and thus, the Weiss ring and vitreous opacities cast shadows onto the retina that are perceived as floaters.
A PVD is present in approximately 65% of patients reaching the age of 65 years.4,5 Although most patients grow accustomed to the visual disturbance associated with Weiss rings and other floaters, many find them bothersome.6 Floaters can reduce contrast sensitivity and quality of life.7,8
Three management options exist for symptomatic floaters: patient education and observation, pars plana vitrectomywith a 1-incision Intrector (in which a 1-incision, limited core vitrectomy is performed while visualizing through an indirect ophthalmoscope; Insight Instruments) or a standard 3-port vitrector, and YAG vitreolysis.
Existing literature assessing the effect of YAG laser on the properties of rabbit vitreous has suggested that pathologic disruption may occur with laser application in the middle or posterior vitreous.9 There are limited published studies on the effect of YAG vitreolysis for treating symptomatic floaters in humans. Small, uncontrolled cases series6,10,11 assessing YAG vitreolyisis report some symptomatic success and suggest a good safety profile. No prospective, sham-controlled trials have been performed, to our knowledge. This is particularly important because of the subjective nature of floater related visual disturbance and the potential of placebo effect confounding the efficacy of treatment. Research by Karickhoff12 showed the most robust outcomes when treating Weiss rings. Therefore, the current study evaluated YAG vitreolysis in patients with symptomatic Weiss rings.
Full Paper: YAG Laser Vitreolysis vs Sham YAG Vitreolysis for Symptomatic Vitreous Floaters
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