Evaluating Red Reflex and Surgeon Preference Between Nearly-Collimated and Focused Beam Microscope Illumination Systems.
OBJECTIVE
To evaluate the intensity and stability of the red reflex produced by ophthalmic surgical microscopes with nearly-collimated versus focused illumination systems and to assess surgeon preference in a simulated surgical setting.


METHODS
This two-part evaluation consisted of postproduction surgical video analysis of red reflex intensity and a microscope use and preference survey completed by 13 experienced cataract surgeons. Survey responses were based on bench testing and experience in a simulated surgical setting. A microscope with nearly-collimated beam illumination and two focused beam microscopes were assessed.


RESULTS
Red reflex intensity and stability were greater with the nearly-collimated microscope illumination system. In the bench testing survey, surgeons reported that the red reflex was maintained over significantly greater distances away from pupillary center, and depth of focus was numerically greater with nearly-collimated illumination relative to focused illumination. Most participating surgeons (≥64%) reported a preference for the microscope with nearly-collimated illumination with regard to red reflex stability, depth of focus, visualization, surgical working distance, and perceived patient comfort.


CONCLUSIONS
The microscope with nearly-collimated illumination produced a more intense and significantly more stable red reflex and was preferred overall by more surgeons.


CONCLUSIONS
This is the first report of an attempt to quantify red reflex intensity and stability and to evaluate surgically-relevant parameters between microscope systems. The data and methods presented here may provide a basis for future studies attempting to quantify differences between surgical microscopes that may affect surgeon preference and microscope use in ophthalmic surgery.
The Eye Institute of Utah, Salt Lake City, UT, USA ; John Moran Eye Center, University of Utah Department of Ophthalmology, Salt Lake City, UT, USA.
Robert J
RJ
Cionni
Global Medical Affairs, Alcon Laboratories, Fort Worth, TX, USA.
Ron
R
Pei
Global Medical Affairs, Alcon Laboratories, Fort Worth, TX, USA.
Ramon
R
Dimalanta
Arbor Centers for Eye Care, Homewood, IL, USA.
David
D
Lubeck
cataract surgery; depth of focus; illumination; red reflex; surgical microscope