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EW CATARACT 33 July 2017 field. In addition, he said, reducing aperture will increase depth of field, but at the cost of light transmission. "Some microscopes have a 'depth of field' setting that optimiz- es the aperture to balance depth of field and illumination," Dr. Wade said, referencing Ophthalmic Micro- surgery: Principles, Techniques, and Applications. 2 Dr. Garg pointed out that decreased field size can lead to ocular fatigue, and operative time could be increased due to frequent adjustments. "Make sure to zoom out enough to keep enough perspec- tive," he advised. Dr. Garg said it's important to know the functionality of your microscope. "Current scopes have more buttons/functionalities than traditional scopes—make sure to use them to your advantage," he said. As a final pearl, both Dr. Garg and Dr. Wade mentioned the physi- cian's posture and ocular position. "As ophthalmologists, many of our instruments are prone to poor ergonomic use," Dr. Wade said. "Take your time to make sure the bed height, chair height, foot pedal location, and microscope oculars are all in ergonomically comfortable positions." Dr. Cionni said that he has start- ed using ocular warmers to prevent fogging. "I used to get fogging frequently and since using these devices have never had an ocular fog up while operating," he said. The warmers he uses are from Mastel Precision (Rapid City, South Dakota). EW References 1. Cionni RJ, et al. Evaluating red reflex and surgeon preference between nearly-collimat- ed and focused beam microscope illumination systems. Transl Vis Sci Technol. 2015;4:7. 2. Garg S and Steinert RF. Ophthalmic Micro- surgery: Principles, Techniques, and Applica- tions. SLACK Incorporated. 2014. Editors' note: Dr. Cionni has finan- cial interests with Alcon (Fort Worth, Texas). Dr. Garg has financial interests with Carl Zeiss Meditec. Dr. Wade has no financial interests related to his comments. Contact information Cionni: rcionni@theeyeinstitute.com Garg: gargs@uci.edu Wade: wadem@uci.edu paper showed that focused beam microscopes have a usable red reflex to be 8.7 mm. For a relatively stable patient, this is sufficient to perform a 5 mm to 5.5 mm capsulorhexis." Dr. Wade said he prefers the Lumera microscope (Carl Zeiss Meditec, Jena, Germany), which has a focused illumination beam, but "at the end of the day it comes down to surgeon (and surgical center) preference." Dr. Cionni said he finds that the focused beam of light provides for a slightly crisper, detailed focus. There is a compromise, however, with the smaller depth of focus and loss of red reflex when not centered or if the eye is tilted, he added. "The advantage of a collimated beam is a broader red reflex so that the areas outside of the center of focus are well visualized, even if at the edge of the field of view or if the eye is tilted. One small compro- mise is the possibility of glare off of instruments such as the broad blades we use for the primary incision. The detail with this style of illumination is still exceptional, and since the depth of field is better than with a focused beam, I find that my need to focus up or down is minimized," Dr. Cionni said. As for magnification for mak- ing the capsulorhexis, Dr. Garg uses 16–20x magnification, zooming in enough for focused visualization, and 8–10x magnification for nuclear fragment removal, which he finds gives enough perspective to show what is going on inside the eye. Dr. Wade's general preference is to use whatever magnification allows him to see the majority of the area exposed by the speculum. Dr. Cionni said he performs most of his surgery under low mag- nification to increase depth of field and minimize the need for focus adjustments. "In general, I like to have the magnification at a level that allows me to see the entire eye includ- ing some of the sclera all in one field. This allows me to monitor all aspects of what I'm doing. At times, I will increase the zoom in order to appreciate even finer details, for in- stance, while polishing the posterior capsule," he said. Dr. Wade offered similar thoughts regarding decreased mag- nification for increased depth of In Loving Memory Roger F. Steinert, M.D. December 8, 1950 June 6, 2017

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