An in vivo human demonstration of 23 gauge infusion cannula air forces striking the retina during a fluid/air exchange vitrectomy for macular hole repair.
OBJECTIVE
To demonstrate, in vivo, that infusion cannula forces of air may strike the retina and optic nerve, which may explain why some patients develop post vitrectomy scotomas.


METHODS
Case report.


METHODS
During a vitrectomy for a macular hole, following a subtotal fluid/air exchange using a 23-gauge infusion cannula and a 25-gauge chandelier light, an unusual circular light reflex was noted on the surface of the retina inferior and nasal to the optic nerve.


RESULTS
The light reflex appeared at a position opposite the infusion cannula; rotating the direction of the infusion cannula moved the reflex from an area inferior to the optic nerve to over the nerve and even on the macula. The reflex disappeared when the air infusion was stopped and reappeared when the air infusion resumed.


CONCLUSIONS
Air infusion forces are directed on to the surface of the retina and these forces might damage the retina resulting in post vitrectomy scotomas.
From Poway, California.
Paul E
PE
Tornambe