Lens refilling (Phaco‐Ersatz)

Abstract

AbstractPurpose To demonstrate that the content of the crystalline lens can be replaced in vivo by a polymer designed to mimic the properties of the young lens to restore accommodation while maintaining ametropia, that polymer exchange can be performed anytime during follow‐up and that Phaco‐Ersatz also allows reversibility to IOL implantation in the bag.Methods A safe endolenticular surgical technique was developed to remove relatively hard nucleus via a small capsulorhexis (~1.2mm) by US phacoemulsification (0.7mm titanium tip). The rhexis is closed by a mini‐capsulorhexis valve (~2mm), the polymer injected and then cured by low intensity light delivered by a custom made handprobe. Three families of polymers were developed allowing independent adjustment of the elastic modulus and index of refraction. These polymers were tested in 2 ex‐vivo accommodation simulators (EVASI and II) on human and primate eyes and their biocompatibility assessed in monkeys and rabbits for periods up to 8 months.Results A safe endolenticular surgical technique was developed to remove relatively hard nucleus via a small capsulorhexis (~1.2mm) by US phacoemulsification (0.7mm titanium tip). The rhexis is closed by a mini‐capsulorhexis valve (~2mm), the polymer injected and then cured by low intensity light delivered by a custom made handprobe. Three families of polymers were developed allowing independent adjustment of the elastic modulus and index of refraction. These polymers were tested in 2 ex‐vivo accommodation simulators (EVASI and II) on human and primate eyes and their biocompatibility assessed in monkeys and rabbits for periods up to 8 months.Conclusion Phaco‐Ersatz can be performed safely and is an effective method to restore accommodation. Commercial interest