In the case of stable, but severe/irregular ectasia, it may be best to implant a monofocal (i.e., non-toric IOL), and have the patient fitted for a contact lens postoperatively topography-guided photorefractive keratectomy (PRK) may be an option in some cases as well. Alcon and Johnson & Johnson Vision toric IOLs have also been documented to give good results in these patients. Bausch and Lomb Envista IOLs come in higher toric powers, which can be very helpful in higher levels of corneal cylinder. IOL options for a cataractous eye with post-LASIK ectasia do include toric monofocal IOLs. 16,17 Once the cornea has stabilized (which can take several months), planning for cataract surgery can be performed. Additionally, in the case of progressive ectasia, corneal crosslinking should be performed to halt progression. Though it is unusual to have ectasia progression after age 40-45, it can occur. If ectasia is present, it is necessary to determine if the ectasia is stable or progressing. It is also important to examine the eyes and topography for signs of decentered ablations (Figure 1) as well as post-LASIK ectasia (Figure 2). 1-3,5,6,10,12-15Īlternatively, an extended depth of focus IOL ( Vivity, Alcon Fort Worth TX or Symfony, Johnson & Johnson Vision, Jacksonville FL) may be used with a slightly lower risk of visual aberrations, though near vision may be limited in comparison to trifocal IOLs. It is always advisable to counsel the patient of increased risk of glare, halos, and starburst as well as decreased contrast sensitivity with diffractive multifocal IOLs due to past history of laser vision correction. 1,2,13 If the patient has acceptable preoperative HOA, optimized ocular surface, and is willing to accept the risk of visual disturbance associated with multifocal IOL implantation (and has been educated that an IOL exchange can be performed, if necessary), then it may be reasonable to proceed with a presbyopia-correcting IOL. 1,13 Devices such as the Pentacam (Oculus, Arlington WA), OPD-3 (Marco, Jacksonville FL) and iTrace (Tracey Technologies, Houston TX) can be helpful for measuring HOA. In general, it is recommended for total HOA to be <0.3µm to plan for optimal results with a multifocal IOL. 1-5 Missed refractive result is also possible due to history of LASIK, and the patient should be counseled regarding this and what options are available in such an occurrence (e.g., glasses, IOL exchange, laser vision correction enhancement). 1-5Īdditionally, intraoperative aberrometry can be used to confirm the IOL at time of surgery (e.g., ORA, Alcon, Fort Worth TX). However, we do have excellent resources to get around this for example, post-refractive surgery calculators such as the ones provided by the American Society of Cataract and Refractive Surgery (ASCRS) can help best calculate the appropriate IOL power. Unfortunately, it is quite common for patients to not have access to this data. Any historical data (pre-LASIK keratometry and refraction) is important, as this can help guide IOL selection. When planning cataract surgery, especially with respect to IOL calculations, accurate axial length and keratometry readings are very important. Moreover, if the patient wishes to consider a diffractive premium IOL technology, nuanced assessment of pre-existing aberrations is necessary. With any patient who is post-LASIK, a scrutinizing examination of the ocular surface, topography, tomography, and higher order aberrations (HOA) is critical. 1,2,5 Preoperative considerations for cataract surgery after LASIK Was the patient previously diagnosed with cataracts prior to LASIK surgery? Are cataracts acute or in relation to trauma or systemic disease? These factors all play a role in surgical planning. However, if the patient is presenting for a cataract evaluation within a few months of LASIK surgery, it is important to investigate why (e.g., what are the relevant patient complaints). In general, cataract surgery is performed years after LASIK there is no time limit (short or long) for when cataract surgery can be done after a patient has had LASIK. When to consider the timing of post-LASIK cataract surgery 1-6Īlthough cataract surgery can be successfully performed after LASIK, it is important to carefully detail preoperative steps, as well as patient education, to ensure optimal visual results. 1-4 However, intraocular (IOL) calculations and meeting patient expectations can sometimes prove challenging after a patient has had laser vision correction the combination of possible inaccurate biometry, variable refractive targeting, and high patient expectations regarding visual outcome requires extra steps on the surgeons’ behalf. A growing number of patients who have had previous laser refractive surgery are presenting to our practices for cataract surgery.
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