Perfluorinated organic liquid as an intraocular oxygen reservoir for the ischemic retina.
OBJECTIVE
Liquid perfluorocarbons are used as temporary vitreous substitutes in the surgical management of complicated retinal detachment. The purpose of this study was to determine if physiologic benefits could also be derived from the high oxygen solubility of perfluorochemicals relative to vitreous, especially during retinal ischemia.


METHODS
The normal vitreous humor of the rabbit eye was replaced with either perfluorotributylamine (FTBA) or balanced salt solution (BSS). Retinal ischemia was then induced by increasing the intraocular pressure above the peak systolic blood pressure for intervals of 10, 30, or 90 minutes.


RESULTS
Over a 10- or 30-minute period of ischemia, during which electroretinographic (ERG) responses were recorded, FTBA-filled eyes and BSS-filled eyes showed decreases in the a- and b-wave amplitudes. However, wave amplitudes were significantly greater in FTBA-filled eyes at most times examined (P < .05). ERG responses were maintained throughout a 30-minute ischemic interval in oxygenated FTBA-filled eyes, but not in oxygenated BSS- or deoxygenated FTBA-filled eyes. When examined 1 day after a 90-minute interval of ischemia, oxygenated FTBA-filled eyes maintained 45% and 57% of the preischemic ERG a- and b-wave amplitudes, respectively, compared to a 5% and 3% retention of wave amplitudes in oxygenated BSS-filled eyes. On light microscopic examination of these eyes, FTBA-exposed retinas showed less ischemic damage than BSS-exposed retinas.


CONCLUSIONS
When used as a vitreous substitute, FTBA exerts a neuroprotective effect on the ischemic retina that appears to relate to an increased retinal oxygen supply compared to BSS.
Wilson
C A
CA
Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas 75235-9057.
Berkowitz
B A
BA
Srebro
R
R
D000818:Animals; D004337:Drug Carriers; D004596:Electroretinography; D005466:Fluorocarbons; D007511:Ischemia / Q000473:pathology / Q000503:physiopathology*; D007552:Isotonic Solutions; D008297:Male; D010100:Oxygen / Q000502:physiology*; D011817:Rabbits; D012160:Retina / Q000473:pathology / Q000502:physiology; D012171:Retinal Vessels / Q000473:pathology / Q000503:physiopathology*; D014821:Vitrectomy; D014822:Vitreous Body / Q000187:drug effects
D004337:Drug Carriers; D005466:Fluorocarbons; D007552:Isotonic Solutions; C008807:perfluorotributylamine; D010100:Oxygen