Interlenticular opacification (ILO) is a recognised complication of piggyback intraocular lenses (IOLs). The aetiology, histopathology, and treatment are not clearly defined, however.Two pairs of AcrySof IOLs were explanted from a patient with bilateral ILO. The explantation technique and surgical challenges of IOL exchanges are described. The explanted IOL complexes and a sample of the anterior capsule were examined by phase, polarising, and immunofluorescence microscopy.A 50 year old man developed ILO bilaterally after piggyback AcrySof IOL implantation. A central contact zone was surrounded by a homogeneous paracentral opacity possibly consisting of extracellular matrix previously laid down by proliferating lens epithelial cells (LECs). These opacities were in turn surrounded by interlenticular Elschnig pearl-type opacities contiguous 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 separated with the help of high viscosity viscoelastic before a single one piece PMMA IOL implantation via large limbal incisions. The sample of anterior capsule showed a ridge configuration from the piling of LECs in the site of apposition with the anterior capsule and cells showing different characteristics on either side of the ridge.Cellular proliferation, deposition of ECM from proliferating LECs, and capsular changes induced by cell metaplasia may lead to ILO formation in piggyback AcrySof IOLs. Careful separation of the AcrySof IOL complex from the capsule, meticulous clean up of the proliferating material, and implantation of single or dual in the bag PMMA IOLs through a large incision with capsulorrhexis enlargement may help in the prevention of recurrence of interface opacification.