Octafluorocyclobutane in vitreous and aqueous humor replacement
G. A. Peyman, C. M. Vygantas, T. O. Bennett, A. M. Vygantas and S. Brubaker
Vitreous replacement with air, pure octafluorocyclobutane (C4F8), and
mixtures of 40% C4F8 and 60% air was done in owl monkeys to determine
ocular toxicity and duration of gas within the vitreous compartment. Large
volumes of gas mixture and pure C4F8 caused posterior subcapsular cataract
formation. Pure C4F8 expands in the vitreous within 24 to 48 hours. A
1.0-ml mixture of 40% C4F8 and 60% air lasted 12.7 days and did not cause
ocular changes. However, anterior chamber aqueous replacement with pure
C4F8 or gas mixture resulted in cataract production. Twenty-four and
fourty-eight hours after injection of 0.1-ml pure C4F8 in the vitreous of
experimental rabbits, presence of oxygen, nitrogen, and carbon dioxide was
shown by gas chromatographic analysis. This finding supports the hypothesis
of volume expansion secondary to diffusion of above-mentioned gases inside
the C4F8 gas bubble.