Our podcast yesterday (the top podcast in all of ophthalmology) featured Dr Robert Weinstock where he described an unusual case where his patient had a very high degree of corneal astigmatism that would be beyond the correction of the highest power toric IOLs that we have in the USA. The highest toric power that is FDA approved has 6 diopters of correction on the IOL which addresses about 4 diopters at the corneal plane. To help his patient, he decided to implant two toric IOLs in the capsular bag to achieve 8 diopters of astigmatic balancing at the corneal plane. This is the video of that case. Now you may be asking about doing a primary piggyback IOL with both IOLs in the capsular bag and whether there will be inter-lenticular accumulation of lens epithelial cells… well, you will have to listen to the podcast to get his answer.
what are thoughts of fibrosis / membrane forming between 2 iols of same material?
I would be concerned about interlenticular opacification which Johnny Gayton reported with 2 Acrysof IOLs. This has NOT been reported with other IOLs but only with 2 Acrysofs in contact and if both are in the bag it would be a very challenging problem to fix:
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