Operative difficulties in removal of retained intraocular foreign bodies by vitreous surgery

The presentation deals with operative difficulties during vitreous surgery for the removal of long-retained intraocular foreign bodies (IOFBs). The cases described and the problems discussed are: (1) IOFBs embedded deeply in dense fibrous tissue which cannot be exposed and removed, (2) IOFBs located in a 'dead space' at the anterior pars plana and ciliary body regions, (3) readherence of a residual stump causing traction retinal detachment, and (4) abnormal hyperviscosity of the vitreous in perforation injuries with long-standing retained IOFBs, without vitreous hemorrhage. The presentation shows that an envelope of dense fibrous tissue does not prevent the spread of metallic ions. It emphasizes that an early surgery, before fibrous organization develops, is imperative.