Nd:YAG Laser Induced Microfragmentation in Intraocular Lenses: A Correlative Optical and Raman Spectroscopy Study.

Abstract

Purpose: Neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy is among the most frequently performed postoperative procedures in pseudophakic patients. Despite its widespread use and generally favorable safety profile, its potential to release solid-phase polymer debris from intraocular lenses (IOLs) has not been fully characterized. In this study, we investigated whether clinically relevant laser settings can cause the liberation of detachable fragments from both hydrophobic and hydrophilic acrylic IOLs.

Methods: Six commercially available one-piece IOLs were exposed to 2.6 mJ single-pulse Nd:YAG laser shots under standardized in vitro conditions. Microscopic evaluation before and after ultrasonic cleaning was performed. Raman spectroscopy was used to identify the chemical composition of any released fragments.

Results: Fragments adjacent to YAG-induced pits were observed in all lens types. Raman spectroscopy confirmed that the fragments matched the chemical signature of the respective IOL material. After sonication and filtration, identical Raman spectra were obtained from fragments retained on gold-coated filters, confirming their origin from the lens surface. Fragment sizes ranged from 10-20 µm.

Conclusions: This study demonstrates that solid IOL-derived fragments can be released by standard laser energy levels used in posterior capsulotomy. Although conducted in vitro, the findings raise concerns about the potential clinical relevance of laser-induced material release. Free-floating debris may contribute to straylight, glare, increased intraocular pressure, or inflammatory responses. Further clinical studies are warranted to systematically assess whether such microfragments lead to postoperative complications. Optimized laser parameters and precise focusing are recommended to minimize structural damage and fragment release.