Supplementary Material for: Reversible opacification of intraocular lens in vitro: case report

Introduction: We reported a case of late-onset opacification of a hydrophilic acrylic intraocular lens (IOL) that developed years after uneventful phacoemulsification cataract surgery. Remarkably, the calcification-related opacification was successfully reversed in vitro using ethylenediaminetetraacetic acid (EDTA).
Case Presentation: An 86-year-old male presented with a two-year history of progressive visual decline in the right eye (best-corrected visual acuity: 2/200). Slit-lamp examination revealed posterior capsular opacification (PCO), and B-scan ultrasonography showed dense vitreous opacities, precluding fundus and optical coherence tomography (OCT) examinations. He had undergone cataract surgery with implantation of a Rayner monofocal IOL ten years ago. As for the treatment of vitreous opacities, PCO, as well as investigating fundus diseases, the pars plana vitrectomy was performed. After PCO removal, fundus visualization remained poor. Intraoperative inspection revealed diffuse opacification of the IOL, which was subsequently explanted. Following removal of IOL, fundus examination revealed non-proliferative diabetic retinopathy and asteroid hyalosis. In vitro, the IOL exhibited homogeneous opacification resistant to mechanical cleaning and soaking in sterile water for one week. However, immersion in 4% EDTA gradually restored full optical clarity over the course of one month. Scanning electron microscopy (SEM) demonstrated small subsurface pits suggestive of prior crystal deposition. Energy-dispersive X-ray spectroscopy (EDS) detected only carbon (C) and oxygen (O), without evidence of calcium (Ca), silicon (Si), or phosphorus (P).
Conclusions: This case highlighted the potential reversibility of hydrophilic IOL opacification through EDTA chelation, suggesting a promising direction for therapeutic management of IOL calcification in vivo in the future.