A strong beam of light (laser) is used to seal off bleeding blood vessels in the eye and to burn away extra blood vessels that should not have grown there.

• 激光凝固治疗是用强的激光束使眼底病变部位出血的血管封闭，它能减轻视网膜水肿、改善循环及消灭新生血管，起到阻止病变发展的作用。