sentences:  Inverse hypopyon is seen after a pars plana vitrectomy with an insertion of silicone oil (as a replacement of the vitreous humour that has been removed in the operation; the silicone oil maintains internal tamponade).When the silicone oil emulsifies, it seeps into the anterior chamber and settles at the top of the anterior chamber.This is in contrast to hypopyon resulting from toxins where the leukocytes settle at the bottom of the anterior chamber.