The use of air from the infusion line to confirm infusion tip positioning in vitreous surgery for eyes with media opacities

To demonstrate the use of an air bubble in infusion to ascertain infusion tip (IT) positioning before commencing vitreoretinal surgery (VRS) in eyes with media opacities. Methods: Twenty-four eyes were studied. An air bubble was introduced into the IT by manually expelling fluid from the distal end of the IT. Passage of this air bubble into the vitreous cavity immediately on opening the infusion line confirmed IT position and VRS was commenced only after this event. Results: The air bubble was seen within the eye in 18/24 eyes immediately on opening the infusion line. In 6 eyes, the air bubble did not exit the infusion line, and VRS was commenced only after IT position was confirmed by other methods. In all 24 eyes, no untoward effect attributable to the air bubble was noticed during subsequent VRS. Conclusions: An air bubble introduced into the IT helps to quickly confirm IT position when direct visualization of the IT is difficult. There were no untoward events in eyes where the air bubble could not enter the vitreous cavity.