A new technique for separation of posterior vitreous in vitreous surgery.

To describe a new and effective technique, hydroseparation, for use in detaching the posterior cortical vitreous from the retina by the simple injection of fluid into the subhyaloid space. This technique was used in 7 eyes of 6 patients with diabetic retinopathy who had limited posterior vitreous detachment. Following core vitrectomy, a 32 gauge cannula was inserted into the subhyaloid space and a balanced salt solution (BSS) was injected. The injected fluid spread easily to the periphery, causing the vitreous cortex to be smoothly separated, except for areas with firm vitreoretinal adhesion. In those areas, we also used microscissors to separate the tissue. No iatrogenic retinal break occurred in any case. This simple technique, which exerts minimal traction force on the retina, was safe and useful for inducing posterior vitreous detachment in patients with diabetes.