Comparative study of vitreous oxygen tension in human and rabbit eyes

For the first time, vitreous oxygen tension in the human vitreous body was measured using a polarographic oxygen electrode during vitreous surgery. The same method was used in a rabbit experimental model. In the human eye, the mean oxygen tensions of the anterior peripheral vitreous body, central vitreous body and posterior vitreous body were 16.7 +/- 3.7 mm Hg (mean +/- 1 SD), 15.9 +/- 2.8 mmHg and 19.9 +/- 4.8 mm Hg, respectively, while the preretinal oxygen tension of the detached retina was 30.0 +/- 4.8 mm Hg. In the rabbit eye, the mean oxygen tensions of the anterior peripheral vitreous body, central vitreous body and posterior vitreous body were 13.9 +/- 4.3 mm Hg, 16.0 +/- 3.5 mm Hg and 22.5 +/- 2.1 mm Hg, respectively. The preretinal oxygen tension of the attached retina in the rabbit eye was 39.5 +/- 3.4 mm Hg, while that of the detached retina decreased to 4.3 mm Hg. When comparing human with rabbit eyes, it appears that the vitreous oxygen tensions are similar, except over the detached retina, even though the ocular circulation differs. We believe that human retinal vasculature plays an important role in perfusing the detached retina with relatively high levels of oxygen.