EyeWorld India March 2016 Issue

39 EWAP Cataract/IOL March 2016 patient has greater than 3 or 4 D of astigmatism, the uncorrected visual acuity will not allow them to see well and even corrected will not match that attained with a toric lens. “As we know, the quality of vision above 1.5 D is just not as good when trying to spectacle correct as compared to being able to do it in an intraocular lens format,” Dr. Yeu said. Dr. Berdahl cautioned that putting in a toric lens in some of these patients can do more harm than good. For example, if you think that the patient will need a specialty contact lens afterward, you do not want to use a toric lens, he said. “You can’t just put a toric lens in an irregular astigmatism patient and think if it doesn’t work, they’ll wear a gas permeable contact lens; now that gas permeable contact lens becomes more expensive and harder to fit because it’s a toric gas permeable contact lens,” Dr. Berdahl said. Overall, Dr. Yeu is very optimistic about the success in treating the irregular astigmatism patient these days. “I think that we’re blessed to be in a stage where refractive cataract surgery has opened up all of these technology options to improve patient visual acuity,” she said, adding that with 50% of patients saddled with visually significant corneal astigmatism, she is looking forward to seeing what other platforms can do in the future. EWAP Editors’ note: Drs. Berdahl and Yeu have financial interests with Abbott Medical Optics (Abbott Park, Ill.), Alcon (Fort Worth, Texas), and Bausch + Lomb (Bridgewater, NJ). Contact information Berdahl: john.berdahl@vancethompsonvision.com Yeu: eyeulin@gmail.com Views from Asia-Pacific Johan A. Hutauruk, MD Director, Jakarta Eye Center Jl. Cik Ditiro 46, Menteng, Jakarta 10310, Indonesian Tel. no. +62-21-2922-1000 Fax no. +62-21-2569-6099 johan.hutauruk@jec.co.id O n ‘When the bowtie is askew’ Most of our patients who have cataract are elderly people and some of them already have tear deficiency problems. LASIK touch-up after cataract surgery is not an option for this group of patients, although this approach will give the best results for patients with normal corneas but have irregular astigmatism. My personal approach to assess the problem is using Scheimpflug tomography of the cornea to perform a precise and complete measurement and analysis of the cornea. This examination is certainly helpful to determine the diagnosis or to exclude any other cornea pathology such as forme fruste keratoconus, mild corneal scars, and irregularities. This will also be helpful in giving the patients an explanation to manage their expectations after cataract surgery. Toric IOLs or Limbal Relaxing Incisions? In my experience, for cataract patients with astigmatism my first option is to offer them toric IOLs. The higher the degree of astigmatism, the higher the chance for the patient to get better uncorrected vision after surgery compared to non-toric IOLs. Even for patients with asymmetric bowtie we can still place the axis of the IOL according to the topography findings and will result in lower residual astigmatism after surgery. For lower astigmatism of less than 1.0 D, my approach is using femtosecond cataract surgery, always placing a pair of limbal relaxing incisions in as peripherally on the cornea as possible. The length and depth of LRI using the femtosecond laser is more predictable compared to manual incisions using blades. For all cases, I don’t use the femtosecond laser to create the main incision and secondary incision while performing the cataract surgery for two reasons: (1) it is faster and easier to create an incision with diamond blades, and (2) the location of the incision sometimes coincides with the steeper axis of the astigmatism, making it more difficult to place the limbal relaxing incisions correctly. But of course this approach must be confirmed with Scheimplfug tomography to exclude any signs of keratoconus or other corneal degenerations. On ‘Cataract surgery in eyes with compromised corneas’ I will never put any kind of multifocal IOL in a patient with compromised corneas, since those kinds of lenses somehow reduce the maximum energy of light reaching the macula. The unhealthy cornea itself already reduces some of the energy, so certainly monofocal IOLs will help patients see better at least for distance vision. It is important to measure the asphericity of the cornea; then we can choose the type of lens with an asphericity number to match the cornea, and this can be done with a corneal topography device. The most common patients with compromised corneas in my practice are patients with low endothelial counts due to conditions such as Fuchs’ dystrophy. The availability of femtosecond laser cataract surgery is most useful for this type of patient, helping surgeons reduce the ultrasound energy needed to perform safe phacoemulsification. I also avoid the use of toric IOLs in this kind of patient; in case we need to perform a lamellar keratoplasty procedure in the future such as DSAEK, it will be difficult to correct the astigmatism. The second most common cases are patients with pterygium, which is not so difficult to manage as long as we encourage the patient to remove the pterygium and wait for 3 months before cataract surgery. The remaining corneal astigmatism should be easy to manage. It is my routine to give artificial tears to all patients with compromised corneas after cataract surgery since elderly patients almost always have tear deficiency problems compared to younger individuals. These artificial tears will help improve vision in patients with corneal irregularity and also help reduce the burning sensation while using antibiotic + steroid eye drops for postoperative care. Preoperative preparation For patients with compromised corneas, it is very important to avoid unnecessary difficulties or complications during cataract surgery. So for each patient, I always give nonsteroidal anti-inflammatory eye drops to be used at least 3 days before surgery. This will help maintain the dilated pupil and we all know that smaller pupils will be more challenging and take more time to complete the surgery. Editors’ note: Dr. Hutauruk declared no relevant financial interests.