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EW CATARACT 35 November 2015 by Mitch Gossman, MD utilizing a fine ray marker, with the patient in the upright posi- tion," he said. 2. Pendulum marker 3. Bubble level marker 4. Electronic level and marker 5. YAG laser marking at 3:00 and 9:00 or final desired orientation 6. Comparison to preoperative photograph or drawing 7. At slit lamp, mark at 3:00 and 9:00 A survey was performed of 55 practicing ophthalmologists who volunteered to participate from the ranks of participants of the eyeCONNECTIONS online commu- nity and volunteers around the U.S. Responses are anonymous in order to encourage candor. Y ou have identified a pa- tient with a cataract who elects to have surgery, and as happens often, he is also excited about the prospect of better uncorrected visual acuity as a bonus of undergoing medically necessary cataract surgery. His refraction clues you in that he may have significant postoperative astigmatism after cataract surgery with a conventional IOL. Sure enough, your patient's biometry discloses considerable corneal astig- matism with your favorite method of projecting postoperative refractive cylinder after taking into account the cataract surgery incision and the patient's posterior corneal astigma- tism. The patient has decided to receive a toric IOL. You plug these factors into your favored formula for projecting the magnitude and axis of astigmatism and determine the exact orientation required for your chosen toric intraocular lens. How do you implant the IOL at that exact orientation to correct for the astig- matism? Unfortunately, the rota- tional orientation of the eye changes when patients lie down, and we do not operate on them in the standing position, so we need a way to know where the horizontal is when the head is upright, somehow find this on the patient's eye before surgery, and orient the IOL with respect to this on the OR table. Some of the methods that have been described are (deliberately excluding methods such as Verion [Alcon, Fort Worth, Texas]): 1. Mark an arbitrary position on the eye when seated, e.g., 3:00 and 9:00 or 6:00 and 12:00, by hand. According to Louis "Skip" Nichamin, MD, Vail, Colo., we humans have a surprising ability to "judge" straight line align- ment, generally referred to as vernier acuity. "For this reason, my preferred manual technique is to place two radial lines on the cornea, one oriented from 6:00 to 12:00 and one from 3:00 to 9:00 How are we aligning our toric IOLs? Pendulum maker 20% Bubble marker 2% Electronic device to indicate level 2% Nd:YAG corneal stroma mark 4% Hand-mark 3:00 and 9:00 estimated by naked eye 35% Hand-mark 6:00 estimated by naked eye 15% Comparison to office photograph 5% Written or drawn existing landmarks 2% At slit lamp, mark at 3:00 and 9:00 15% Toric IOL implanted during surgery The patient's postop visit the following day Source: Mitchell Gossman, MD torque the marker so the second prong contacts the eye out of level. 2. Nd:YAG stromal markings: I have done about a dozen of these, and the method does work most of the time but not 100% of the time, and they can be difficult to see especially if not surrounded by red reflex. I found myself doing a backup marking method in case the YAG marks are not visible. 3. I have not used the "by eye" estimation and marking of level (or 6:00) for actual implantation, but I have experimented with this in conjunction with my favored method as a trial and indeed have noticed no meaningful difference, so this "guesstimate" method is potentially very precise. continued on page 36 Pulse of ophthalmology: Survey of clinical practices and opinion Mitch Gossman, MD I have personally tried several of these methods and have identified some issues with all of them. 1. Pendulum marker: Because the two inked marking prongs are held level by the weight of a plumb bob, it is possible for the first prong to touch the eye and

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