Purpose:
To determine if perfluoro-n-octane deflects a dropped metal foreign body from hitting a target more than balanced salt solution.
Methods:
A model of intraocular foreign body removal was constructed. Metal objects were dropped into a cylindrical plastic container filled with balanced salt solution (BSS) and/or perfluoro-n-octane. A linear portion of a steel nail (5 x 1.5 mm) and the round head of a steel screw (5 mm diameter, 2 mm thick) were grasped with intraocular forceps and dropped directly above a target. The container was filled with BSS or perfluoro-n-octane to a depth of 10 mm, and the metal object was released in air from a height of 18 mm. The test was repeated with the container completely filled with BSS or a combination of perfluoro-n-octane (10 mm deep) under BSS. Each object was then submerged in the BSS and dropped from a height of 18 mm. The test was repeated 10 times in each fluid and video recorded. The video was reviewed, and the distance from the impact site to the center of the target was measured and recorded. The mean distance from the target for the two objects in each fluid was compared using the Student t test.
Results:
The mean impact site distances from the target are shown in Table 1. Perfluoro-n-octane did not result in a statistically significant difference compared to BSS for each object. The mean distance was <1mm for each scenario, which indicates neither fluid significantly alters the impact site of a dropped metal foreign body.
Conclusions:
Perfluoro-n-octane did not deflect a dropped metal foreign body more than balanced salt solution. Neither fluid deflected the objects a clinically significant amount and neither would protect the macula if a foreign body was dropped over it during attempted removal.
Keywords: trauma • vitreoretinal surgery