Scanning electron microscope study on the biodegradation of IOL and suturing materials.

The biodegradation of the IOLs (27 cases: mainly prepupillary lens with pupillary fixation, irido-capsular and angle supported lens and a J loop lens for posterior chamber lens) and suturing materials of four cases have been studied by Scanning Electron Microscope (SEM). The longest duration in the eye was 7.5 years and the shortest 0.3 year. The materials used for optics were PMMA with the exception of one case of glass. The materials for haptics were Nylon 6, Isot.PP, PMMA, PVDF, Polyimid and Pt-Ir. The suturing materials were Nylon 6 and Isot.PP. Nylon 6 degraded in the eye and Isot.PP degraded in the corneal tissue. But no biodegradation was observed in Isot.PP, PMMA, PVDF and Pt-Ir in the eye. In our investigations, biodegradation has some relationship to age (over 50 years old), duration (within 7.5 years) and inflammation of the eye, but ultimately biodegradation will depend on the individual situation. Degradation occurs most easily in the curved portion of Nylon 6.