A comparison between an acetazolamide test and weight tonography in pathological and apathological circulation of the aqueous humor.

Abstract

In a total of 92 eyes in 46 individuals the outflow facilities obtained by weight tonography, Cton correlated curvilinearly with those estimated by an acetazolamide test, Cacet. The presumed apathological pairs of eyes were those with Cacet above (or equal to) 0.15 and pressure symmetry (right/left). Twenty-one patients referred for glaucoma suspicion (and three normal test persons) showed these characteristics. The eyes appeared clinically healthy even if the pressure range reached 30 mm. Hg. Here Cacet averaged 0.32 but Cton only 0.16; the discrepancy is possibly caused by the outflow obstruction brought about by the high pressures during weight tonography. The presumed pathological eyes (33 from 20 individuals referred for glaucoma suspicion or manifest glaucoma) were those with Cacet below 0.15. They generally showed pressure asymmetry and in some cases pressure values above 30 mm. Hg, and there were in several cases other glaucomatous signs. In this group Cton and Cacet were similar; both averaged 0.09. The acetazolamide test is considered more informative than weight tonography because the test provides at the same time an estimate of the outflow facilities in the normal- or low-pressure range as well as an accurate comparison between the pressures and outflow facilities of the two eyes. The test is time-consuming, however (1 to 11/2 hours).