Interlenticular opacification in piggyback AcrySof intraocular lenses: explantation technique and laboratory investigations

Background/aims-Interlenticular opacification (ILO) is a recognised complic ation of piggyback intraocular lenses (IOLs). The aetiology, histopathology , and treatment are not clearly defined, however. Methods-Two pairs of AcrySof IOLs were explanted from a patient with bilate ral ILO. The explantation technique and surgical challenges of IOL exchange s are described. The explanted IOL complexes and a sample of the anterior c apsule were examined by phase, polarising, and immunofluorescence microscop y. Results-A 50 year old man developed ILO bilaterally after piggyback AcrySof IOL implantation. A central contact zone was surrounded by a homogeneous p aracentral opacity possibly consisting of extracellular matrix previously l aid down by proliferating lens epithelial cells (LECs). These opacities wer e in turn surrounded by interlenticular Elschnig pearl-type opacities conti guous with the same material filling the periphery of the capsular bag. The IOL complexes were very adherent to the capsular bag and they had to be se parated with the help of high viscosity viscoelastic before a single one pi ece PMMA IOL implantation via large limbal incisions. The sample of anterio r capsule showed a ridge configuration from the piling of LECs in the site of apposition with the anterior capsule and cells showing different charact eristics on either side of the ridge. Conclusion-Cellular proliferation, deposition of ECM from proliferating LEC s, and capsular changes induced by cell metaplasia may lead to ILO formatio n in piggyback AcrySof IOLs. Careful separation of the AcrySof IOL complex from the capsule, meticulous clean up of the proliferating material, and im plantation of single or dual in the bag PMMA IOLs through a large incision with capsulor-rhexis enlargement may help in the prevention of recurrence o f interface opacification.