Clinical manifestations of posterior precortical vitreous pocket in proliferative diabetic retinopathy.

BACKGROUND: In diabetic retinopathy, fibrovascular tissue is prone to form around the macular area in a circular pattern. Posterior precortical vitreous pocket is a physiologically presented premacular liquefied lacuna of the vitreous. The authors studied how a posterior precortical vitreous pocket affects the clinical feature of proliferative diabetic retinopathy (PDR).
METHODS: The authors examined the vitreous of 148 diabetic eyes from 114 patients with a ring- or C-shaped fibrovascular tissue surrounding the posterior fundus.
RESULTS: A cone-shaped partial posterior vitreous detachment was a common feature of the vitreous. A posterior vitreous detachment was prevalent outer to the ring-shaped proliferation. In the posterior fundus inner to the ring, only the gel component of the vitreous was detached from the fundus with the cortical vitreous still attached onto the retina. The premacular liquefied lacuna was identified as the posterior precortical vitreous pocket. The profile of this pocket became obvious when vitreous hemorrhage settled within the posterior precortical vitreous pocket. The ring-shaped proliferation was formed along its the outer margin.
CONCLUSION: These results suggest that a posterior precortical vitreous pocket plays a key role in determining the pattern of proliferation in some types of diabetic retinopathy.