Techniques and Strategies
Dr. Steinert: With the white mature lens, for example, that is under pressure, then the 1 and one-half or so seconds of the capsulotomy, you get through fast enough that you have never seen an Argentinean flag sign?
Dr. Dick: No, and there are different approaches. Because of the high-resolution OCT, you can see whether there is a higher pressure in the lens. You see this cavitation and the pressure behind it if this is the case. Sometimes you don't see it at the slit lamp to that extent -- with the Morgagnian cataract, for example -- and in these cases, if you can't go into the eye first because the laser is outside or something like that, I would prefer to do a small capsulotomy first and then later on re-dock or do a manual capsulotomy, re-shoot, and do a rhexis shaping, for example.
Dr. Steinert: For dealing with the small pupils, what is your preferred technique now?
Dr. Dick: I have a strategy. I start with epinephrine injection. If this doesn't work I do a viscomydriasis with high-viscosity OVD. You have to increase the treatment zone of the capsulotomy a little bit because in the diagnostic pathway, as well as the laser pathway, it's a little bit changed, because the refractive index of the OVD and the anterior capsule may not be the same as the aqueous humor. So you have a little offset, but you can compensate this by elevating the treatment zone. You also have to elevate the energy if you are using OVD and viscomydriasis, because it's dampened a little bit, and the effect is reduced by the high-viscosity OVD. If this doesn't work, perhaps because a 5.5 pupil size is needed, then I inject a Malyugin ring. It's available in different sizes. Others may use an iris hook, which works very well with this interface because you can take the iris hook inside this interface.
Dr. Steinert: You anticipated what I was going to ask you.
Dr. Dick: It's better to have the OVD out for the lasing. The results were good but were even better in the prospective study if we took the OVD out.
Dr. Steinert: Is that because of the focusing and the optical breakdown?
Dr. Dick: Yes.
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