SURGICAL DEMONSTRATION OF PRESSURE DIFFERENTIAL THROUGH AN OPTIC DISK PIT.

Purpose: To demonstrate intraoperative dynamic flow through an optic disk pit.

Methods: Retrospective interventional case report.

Results: Surgical management of an optic disk pit involved standard, 25-gauge, pars plana vitrectomy, induction of posterior hyaloid separation with triamcinolone stain, temporal peripapillary laser, and SF 6 gas. Intraoperatively, a remnant of stained vitreous at the optic disk head prolapsed into the optic disk pit with higher intraocular pressure but was drawn back into the vitreous cavity as the intraocular pressure was lowered. This clearly demonstrated a pressure differential across the pit.

Conclusion: Communication between the vitreous cavity and the perineural space of the optic nerve is described histologically. Our case demonstrated dynamic flow through the optic disk pit with intraoperative fluctuation of intraocular pressure.