OphthalmologyWeb Daily Coverage of the AAO Meeting
David Goldman, MD
Refractive editor
The first of day of the refractive subspecialty meeting was full of great presentations. Though presenters disclosed their respective financial relationships, some presentations still appeared biased. Two hot topics for the day were Sub-Bowman Keratomielieusis (SBK) and the correction of presbyopia with intracorneal inlays.
SBK involves the creation of a thin flap (approximately 100 um) with a femtosecond laser. Excimer laser is then performed on the stromal bed in the same manner as traditional LASIK. Many physicians feel that this may represent the “best of both worlds” by combining the quick rehabilitation of LASIK with the safety of surface ablation. Dr. Durrie presented research showing roughly equivalent corneal hysteresis values between eyes treated with SBK and those treated with surface ablation.
My impression: SBK is a fancy term for thin flap LASIK. Most would agree that the more residual stromal thickness left, the more stable the cornea is. On that note, SBK is certainly preferable to thicker flap LASIK. However, it is very possible that surface ablation weakens the cornea less than SBK. Dr. Durrie corroborated this point by urging physicians to still perform surface ablation over SBK in cases of unusual topographies.
The afternoon session focused on new treatments for presbyopia. One such treatment is the AcuFocus ACI 7000 corneal inlay. This is essentially a disc with a 1.6 mm pinhole in the center engineered to be placed over the pupil under a 160-170 um flap. Initial study results were very exciting, and the technology itself has the advantage that the inlay can be replaced with stronger powers over time as the patient’s accommodative demands increase.
My impression: The device has a lot of promise. While the inlay did not appear to affect OCT measurements of the macula, I am concerned that retina surgeons may have compromised peripheral views of the retina. Furthermore, cataract surgery itself may be more cumbersome to perform with these lenses in place.