THE BARRIER FUNCTION IN NEODYMIUM-YAG LASER CAPSULOTOMY

Background: Complications following neodymium (Nd)-YAG laser capsuloto my have been attributed to damage to the capsule and vitreous face. Ob jectives: To measure the disruption of the anterior-posterior extracap sular barrier complex induced by Nd-YAG laser capsulotomy and to deter mine how it might be minimized, using a fluorophotometer. Design: Pros pective study of 21 eyes undergoing Nd-YAG laser capsulotomy and cross -sectional comparison with 15 pseudophakic eyes with clear capsules. S etting: University-based clinical practice. Intervention: Neodymium-YA G laser posterior capsulotomy per study protocol. Main Outcome Measure : Change in extracapsular barrier efficiency as measured by fluorophot ometry. Results: Multivariate regression demonstrated that both anteri or vitreous disruption and absence of a posterior chamber intraocular lens (aphakia) were significantly correlated with loss of barrier effi ciency, whereas capsulotomy size was not. The anterior vitreous was ju dged to be undamaged in 67% of eyes treated by the study protocol. How ever, all myopic eyes sustained damage. Opacification of the posterior capsule itself was also associated with mild loss of barrier function even before capsulotomy, compared with the clear-capsule group. Glauc oma occurred more frequently when barrier efficiency was lost postoper atively. Conclusion: Damage to the extracapsular barrier complex by Nd -YAG laser capsulotomy is minimized when the anterior vitreous is pres erved. The study treatment protocol may be useful in limiting this dam age and in reducing complications.