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SPECIAL REPORT Comprehensive Clinical Commitee report Special equipment There are no special pre-operative instruments or equipment needed to im- plant premium IOLs. As long as the ability to obtain accurate biometry is available, it is not necessary to use optical coherence methods. It is necessary to have a technician who will take careful measurements, whatever instru- ment is used. Surgical equipment that may be needed include markers for toric lens placement, LRI equipment, and IOL injectors. ASCs and hospitals should provide these. Additionally, manufacturers' representatives may have them available. However, if they are not available, they can be obtained from many of the instrument manufacturers. The astigmatism correction for presbyopia-correcting premium lenses can be accomplished by: • Corneal or limbal relaxing incisions • PRK/LASIK If an excimer laser is not available, many ophthalmologists have part- nered with an ophthalmologist who does have access to laser correction. Surgical techniques The same techniques that lead to successful standard cataract surgery lead to successful premium IOL surgery. Surgical and refractive outcomes are improved by standardizing the size and centration of the capsulorhexis. Some surgeons achieve this by feel, while others use optical zone markers on the cornea or even intraocular to help size the capsule opening. In the future, femtosecond lasers may be a great help with this. Those using accommodating IOLs will need to seek training on capsu- lorhexis sizing goals and how to achieve more consistent vaulting. Success with astigmatism reduction requires accurate determination of the axis. Most surgeons advocate marking either the axis of treatment or the cardinal meridian with the patient seated so that if the eye rotates as the pa- tient lies back, the correct location for astigmatism management can be de- termined. Some use standard surgical marking pens for this task while others use toric marking instruments or systems. Taking vector analysis into account augments success with astigmatism management. There are websites available to help with this process. Intra-op- eratively the surgeon should aim to create a consistent, clear corneal incision so that its astigmatic effect can be incorporated into the refractive planning. A consistent capsulorhexis is important to keep the premium IOL in its cor- rect position. Phaco power modulations should be used during ultrasound delivery in order to minimize the amount of energy placed into the eye. Thorough cleanup of cortical material is desirable to help prevent posterior capsule opacification and capsular fibrosis, particularly with accommodating IOLs. Incisions should have watertight closures to keep the IOLs in their cor- rect position during the post-operative period. Toric IOLs must be placed at the correct alignment and centered with the corneal astigmatism. The viscoelastic should be removed from behind the IOL in order for the optic to have direct contact with the posterior cap- sule. A watertight enclosure of the incision helps to keep the IOL in the cor- rect position. Multifocal IOLs work best when the diffractive rings of the multifocal IOL are lined up with the pupil, or even better, the visual axis. Since this tends to be nasal to the center of the cornea and capsular bag, orienting the multifocal IOL in a vertical position (12 o'clock to 6 o'clock) allows it to be nudged into proper centration. Again, viscoelastic should be removed from behind the IOL and the incision should be watertight. Accommodating IOLs require thorough cortical cleanup, which is thought to aid in the prevention of posterior capsule fibrosis that can alter the IOL's position. The currently FDA-approved accommodating IOL must have a posterior vault in the capsular bag, and care must be taken to ensure that all four haptic arms are completely with the capsular bag. This can be confirmed by rotating the IOL, with any resistance to rotation indicating ei- ther a misplaced haptic arm or significant capsular weakness. The correct po- sition of this lens is the haptic arms at the capsular bag equator and the IOL optic vaulted posteriorly against the posterior capsule. It is critical to have a completely watertight closure in order to keep the IOL in this correct orienta- tion. Any leaking from an incision should be addressed by suture closure. Post-operative care In many ways, post-operative care is similar to cataract surgery with a tradi- tional, monofocal IOL. There are special considerations for these premium lenses, particularly the accommodating IOLs, but this information is best ob- tained by consulting with the clinical specialist available for consultation from each of the lens manufacturers. Presbyopia-correcting lenses may require correction for residual astigma- tism. This can be accomplished either with excimer laser correction or corneal/peripheral corneal incisions. It should not prove to be an obstacle to using premium lenses. Symptomatic spherical errors can be corrected with the excimer laser or with "piggyback" lenses. Patients with multifocal IOLs tend to be very sensitive to secondary membranes and residual astigmatism. However, it is best to postpone YAG capsulotomy until all other means of im- provement have been exhausted. It is important to make sure that patients do not have tear film or ocular surface problems. Just as with refractive surgery, ocular surface problems can adversely affect an otherwise successful surgical procedure. IOL measurements Patient satisfaction is highly correlated with the accuracy of the lens power choice. Attention to pre-operative measurements and calcula- tions will improve your success with premium IOLs. Surgeons should track their results in order to personalize their A-constant for each specific IOL and hone their IOL calculations. Ad- ditionally, surgeons should know the astigmatic effect of their typical clear corneal cataract incision so that they can incorporate this into their astigmatic planning. Additional assistance in calculating lens power can be obtained on the following websites: • www.ascrs.org • www.ascan.net/utility/site_map.htm Post-operative patient concerns Depending on the lens selected, patients may complain of: • Ghosting • Halos • Glare • Distance blur • Inadequate spectacle independence for intermediate or near vision These problems are frequently corrected or minimized by treating ocular surface problems or residual refractive errors. They often im- prove with time, which may take as long as 6 months, as "neuroadap- tation" occurs. Rarely, an IOL must be exchanged to obtain greater patient satisfaction. This rare intervention is within the skill set of the comprehensive ophthalmologist, and if needed should be performed prior to YAG capsulotomy. 36 • May 2011

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