[Effect of hyaluronidase on ocular circulatory changes caused by retrobulbar anesthesia]

Twenty patients had retrobulbar anesthesia with 5 ml mepivacaine (Scandicain) without or with addition of 150 units of hyaluronidase (Kinetin). Before and 15 min after injection, we determined--by means of oculo-oscillo-dynamography--the systolic retinal and ciliary perfusion pressures, the respective ocular blood pressures (intramural pressures) and the ocular pulsation volume (PVoc) as well as the intraocular pressure (Pio; hand-applanation tonometer). Without hyaluronidase, the ocular perfusion and blood pressures were lowered by 11.8 and 3.9 mmHg, respectively, and PVoc was reduced by 0,40 microliters, whereas Pio was increased by 7.9 mmHg With hyaluronidase, the ocular perfusion and blood pressures were decreased by averages of 12.7 and 6.8 mmHg, respectively, PVoc was reduced by 0.42 microliters, and Pio was increased by 6.0 mmHg. Within each group, all changes were significant. There were, however, no significant differences between the two groups, i.e., the "spreading factor" hyaluronidase does not influence the inhibitory effects of retrobulbar anesthesia on ocular circulation.