Intraocular fluid dynamics. Measurements following vitrectomy and intraocular sulfur hexafluoride administration
F. P. Killey, H. F. Edelhauser and T. A. Aaberg
Partial vitrectomies were performed in rabbits, replacing 40% of initial
vitreous volume with 100% sulfur hexafluoride, and concentrations of
sodium, potassium, calcium, magnesium, ascorbate, and protein were
determined in aqueous and vitreous at 10, 14, 21, 28, 56, and 110 days.
There were significant increases of potassium, calcium, magnesium, and
protein above control values at varying times throughout the study.
Vitreous potassium concentration was decreased at 14 and 21 days. All other
measurements were similar to control values. Results of studies indicate
that, following vitrectomy in rabbits, the blood-retinal barrier can
re-form in 14 days and blood-aqueous barrier in ten days. However, a
greater than normal exchange diffusion of these measured substances occurs
between aqueous and vitreous through 21 days. Four eyes with cataracts,
vitreous membranes, and/or detached retinas demonstrated elevated aqueous
and vitreous protein concentrations through 110 days, although other
measurements returned to normal levels.
