Purpose. Povidone iodine has been proven to be a valuable antiseptic soluti
on in preparing the eye for surgery and is an alternative to postoperative
topical antibiotics. No study has addressed the intraocular toxicity of pov
idone iodine after injection into the anterior chamber. We investigated the
potential toxicity of povidone iodine on the corneal endothelium after inj
ections into the anterior chamber in a rabbit model. Methods. In this study
we used 24 eyes of 12 albino rabbits. The eyes were divided into the follo
wing three groups according to the drugs tested: group A, 5% povidone iodin
e; group B, 10% povidone iodine; group C, balanced salt solution. The injec
ted eyes were evaluated by biomicroscopy, specular microscopy, corneal pach
ymetry, and transmission and scanning electron microscopy. Results. Corneal
edema was observed in all eyes of groups A and B. In groups A and C, the e
ndothelial cell morphology was not significantly changed and the mean endot
helial cell count of the eyes did not change significantly (p = 0.5054). Th
ere was no significant difference in corneal thickness between groups A and
C (p = 0.3823), but there was a significant difference between groups B an
d C (p = 0.0002). Transmission and scanning electron microscopy results wer
e normal in group C but not in groups A and B. Conclusion. Povidone iodine
in both 5% and 10% concentrations demonstrates severe toxicity when one dro
p of either concentration is placed directly in the anterior chamber. When
povidone iodine is used in preparing the eye for intraocular surgery and as
an alternative to postoperative antibiotics, the inadvertent leakage of po
vidone iodine into the anterior chamber must definitely be prevented.