QUANTITATIVE ESTIMATION OF METABOLIC TRANSPORT OF SUBRETINAL FLUID

  • 1 November 1986
    • journal article
    • research article
    • Vol. 27  (11) , 1564-1568
Abstract
A new technique to measure the ongoing rate of subretinal fluid resorption inside the living eye is described. Experimental non-rhegmatogenous detachments (blebs) were made in the posterior pole of rabbit eyes by injecting fluid directly into the subretinal space, and the height of these blebs was measured with a YAG laser focusing system utilizing dual He-Ne beams. The resorption rate for Hanks'' balanced salt solution was relatively constant during the initial 2.5 hr, and averaged 0.12 .+-. 0.04 .mu.l/mm2/hr. The resorption rate for blebs made with non-ionic solution (isotonic sucrose) was only 0.03 .mu.l/mm2/hr. The resorption rate for blebs made with Hanks'' solution plus 1 mM DNP was 0.04 .mu.l/mm2/hr. These data support the concept that subretinal fluid is resorbed primarily across the retinal pigment epithelium, and suggests that 70% of this absorption is dependent upon active ionic transport. The remaining 30% is probably driven by the higher oncotic pressure of the choroid.