Cataract Surgery Feature story

Solving Post-LASIK With an Adjustable IOL A good indication for use of the LAL.

By Guillermo Rocha, MD, FRCSC

s surgeons are discovering with increasing on implantation of the LAL, which allows IOL power frequency, calculating IOL power in post-LASIK adjustment after surgery. In eyes with previous refrac- patients is challenging. An IOL with a power tive surgery, this feature offers the ability to optimize the that can be modified following implantation is refractive result. Aone solution to achieving better visual outcomes in these eyes. Recently, I implanted the Light Adjustable (LAL; CALCULATION CHALLENGES, A SOLUTION Calhoun Vision) in a 36-year-old man with a traumatic Due to the corneal alterations induced by refractive cataract who had previously undergone bilateral LASIK.1 surgery, determining the keratometry (K) value and the effective lens position proved to be difficult in this case.2,3 A COMPLEX SITUATION Several strategies and formulas exist for calculating K Two months after undergoing bilateral LASIK in April values in post-LASIK eyes, including the clinical history, 1999, Patient A sustained a work-related injury. Hydraulic Hamed, and Feinz-Mannis methods, which use pre- and fluid entered his left eye at high force, causing the LASIK post-LASIK measurements to calculate IOL power.4-6 In flap to fall off the stromal bed and wrinkle. The original sur- some cases, however, pre-LASIK records are either unavail- geon repaired the flap, but Patient A subsequently devel- able or inaccurate.7,8 Other methods include oped high intraocular pressure, which was then also man- over-refraction, Maloney-Wang, Haigis-L, consensus K, and aged by the original surgeon. After the accident, however, Shammas; phakic autorefractometry can also be used.8-14 visual acuity in his left eye remained poor for several years. Unfortunately, no method is 100% accurate, and the tech- In February 2011, Patient A came to my clinic for a niques are often inconsistent across patients.15 second opinion. Distance UCVA in his right and left eyes I decided to implant the LAL in Patient A’s left eye was 20/25 and 20/160, respectively. The manifest refrac- because it circumvents the need to precisely predict tion in his left eye was -4.75 +1.00 X 130º, with poor IOL power before . After the LAL was pupil response. Slit-lamp examination revealed a superior implanted and the power was adjusted with ultraviolet hinged flap in both eyes and significant droplets in the (UV) light treatments, Patient A achieved a refraction interface in the left eye that were likely oil droplets from of 0.50 D and a distance UCVA of 20/20. Today, he is the hydraulic fluid. Patient A also showed evidence of one of my happiest patients. After many years of prac- an anterior subcapsular spoke-like cataract. Lifting the titioners telling him nothing could be done to improve flap and washing out the oil droplets led to a significant his vision, he was satisfied with his results with the LAL, improvement in higher-order aberrations. including reduced glare. At his next visit 3 months later, manifest refraction and For two other perspectives on Patient A’s case, see distance UCVA in the left eye declined to -5.50 -0.25 X 130º My Surgical Approach on page 41. and 20/200, respectively. Due to the presence of the trau- A few months after treating Patient A, I attended the matic cataract and subjective glare, we discussed options 2011 Canadian Society meeting and lis- for further treatment, including LASIK enhancement fol- tened to Lawrence A. Brierley, MD, of British Columbia, lowed by conventional cataract surgery. Instead, we agreed Canada, present multicenter results with the LAL in post-

40 Cataract & Today EUROPE October 2013 Cataract Surgery Feature story

MY SURGICAL APPROACH Take-Home Message Fritz H. Hengerer, MD • The clinical history, Hamed, and Feinz-Mannis In the case of Patient A, I would have chosen the methods use pre- and post-LASIK measurements proper treatment based on corneal opacity, pupil size, to calculate IOL power. and any scars resulting from the accident. In a traumatic case such as this, it is also crucial to assess the stability of • Other calculations include contact lens over- the capsular bag to provide a reliable outcome. refraction, Maloney-Wang, Haigis-L, consensus K, My first choice would be a three-piece hydrophobic and Shammas; phakic autorefractometry can also IOL because it can be implanted in the capsular bag or be used to calculate IOL power. ciliary sulcus. If I were concerned with capsular bag stabil- • Implanting a lens with a power that can be ity, I would suture the IOL to the sclera using a Cionni modified following implantation avoids the need Ring (Morcher GmbH); the LAL is not suitable for scleral to predict IOL power with pinpoint precision. fixation using sutures. In eyes with wide pupils, I would recommend implant- ing partial or complete aniridia rings such as the Morcher viously undergone LASIK. In these instances, implanting 5E or 5F (Morcher GmbH) to further reduce photic phe- the LAL avoids the need to predict IOL power with pin- nomena. These devices can be implanted intraoperatively point precision and allows me to tweak the lens power or after IOL implantation in a secondary procedure. after surgery based on the patient’s visual acuity and manifest refraction. Fritz H. Hengerer, MD, is the Senior Head This lens has the potential to shift the focus of refractive Physician and Deputy Director at the Hospital predictability from developing more accurate IOL power of the Johann Wolfgang Goethe University in formulas to customizing lens power postoperatively. n Frankfurt, Germany. Dr. Hengerer states that he has no financial interest in the products or com- Guillermo Rocha, MD, FRCSC, practices at GRMC Vision panies mentioned. He may be reached at e-mail: Centre, Brandon, Manitoba, Canada. Dr. Rocha states [email protected]. that he has no financial interests in the products or companies mentioned. He may be reached at e-mail: Tobias H. Neuhann, MD [email protected]. Dr. Rocha used the best available method to enhance Patient A’s vision after cataract surgery. The LAL is cur- 1. Rocha G, Mednick ZA. Light-adjustable intraocular lens in post-LASIK and post-traumatic cataract patient. J Cataract Refract Surg. 2012;38:1101-1104. rently the only implant that can correct miscalculated 2. Randleman JB, Loupe DN, Song CD, et al. Intraocular lens power calculations after laser in situ keratomileusis. IOL power in the postoperative period. In a case like . 2002;21:751-755. 3. Norrby S. Sources of error in intraocular lens power calculation. J Cataract Refract Surg. 2008;34:368-376. this, it is a challenge to calculate the correct power, and I 4. Naseri A, McLeod SD. Cataract surgery after refractive surgery. Current Opin Ophthalmol. 2010;21:35-38. would use a combination of ray tracing and topography. 5. Holladay JT. Consultations in refractive surgery [comment]. Refract Corneal Surg. 1989;5:203. 6. Feiz V, Mannis MJ, Garcia-Ferrer F, et al. Intraocular lens power calculation after laser in situ keratomileusis for and hyperopia: a standardized approach. Cornea. 2001;20:792-797. Tobias H. Neuhann, MD, is the Medical Director of the AaM 7. Wang L, Booth MA, Koch DD. Comparison of intraocular lens power calculation methods in eyes that have Augenklinik am Marienplatz, Munich, Germany. Dr. Neuhann undergone LASIK. Ophthalmology. 2004;111:1825-1831. states that he has no financial interest in the products or com- 8. Diehl JW, Yu F, Olson MD, et al. Intraocular lens power adjustment nomogram after laser in situ keratomileusis. J Cataract Refract Surg. 2009;35:1587-1590. panies mentioned. He may be reached at tel: +49 89 230 8890; 9. Koch DD, Wang L. IOL calculations following refractive surgery. ASCRS Symposium on Cataract, IOL and Refractive fax: +49 89 230 88910; e-mail: [email protected]. Surgery; San Diego, California; April 27-May 2, 2007. 10. Shammas HJ, Shammas MC, Garabet A, et al. Correcting the corneal power measurements for intraocular lens 16 power calculations after myopic laser in situ keratomileusis. Am J Ophthalmol. 2003;136:426-432. LASIK patients. Of 16 eyes treated at three centers, 11. Haigis W, Lege B, Miller N, et al. Comparison of immersion ultrasound biometry and partial coherence interfer- 75% achieved a refraction within ±0.25 D of intended ometry for intraocular lens calculation according to Haigis. Graefes Arch Clin Exp Ophthalmol. 2000;238:765-773. correction and 94% achieved a refraction within 12. Mackool RJ, Ko W, Mackool R. Intraocular lens power calculation after laser in situ keratomileusis: aphakic refraction technique. J Cataract Refract Surg. 2006;32:435-437. ±0.50 D. Like these multicenter study results, my own 13. Ianchulev T, Salz J, Hoffer K, et al. Intraoperative optical refractive biometry for intraocular lens power estimation experience suggests that the LAL can help post-LASIK without axial length and keratometry measurements. J Cataract Refract Surg. 2005;31:1530-1536. 14. Wang L, Booth MA, Koch DD. Comparison of intraocular lens power calculation methods in eyes that have patients achieve excellent visual outcomes after cata- undergone LASIK. Ophthalmology. 2004;111:1825-1831. ract surgery. 15. Chayet A, Sandstedt C, Chang S, et al. Correction of myopia after cataract surgery with a light-adjustable lens. Ophthalmology. 2009;116:1432-1435. 16. Brierley LA. Precision of IOL refractive power adjustment of the Light Adjustable Lens (LAL) in post-refractive DISCUSSION surgery patients. Paper presented at: the Canadian Ophthalmological Society; Vancouver, British Columbia, Canada; Approximately 10% of my cataract patients have pre- June 9-12, 2011.

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