Cataract Surgery After Refractive Surgery

Ravi H. Patel, MD; Carol L. Karp, MD; Sonia H. Yoo, MD; Guillermo Amescua, MD; Anat Galor, MD, MSPH

Disclosures

Int Ophthalmol Clin. 2016;56(2):171-182. 

In This Article

Case Presentations

The following cases highlight some of the challenges in IOL calculations when planning cataract surgery in postrefractive eyes.

Case 1

A 62-year-old white male with a history of RK many years prior presented for cataract evaluation (Fig. 1). Past ocular history was also significant for vitrectomy and scleral buckle surgery 6 months prior in the setting of a macula off retinal detachment with residual macular edema detected by OCT. Preoperative best corrected visual acuity was 20/400 with a 3+ NS and 3+ posterior subcapsular cataract. Preoperative lens calculations with the ASCRS calculator were between 17 and 21D (average 19 D), with the Pentacam (Oculus, Arlington, WA) keratometry value in the SRK/T formula 19.5 D, and with straight SRK/T 16.5 D. On the basis of this information, the preoperative plan was to place an 18.5D 1-piece acrylic lens into the capsular bag and to titrate this measurement with intraoperative wavefront aberrometry (ORA; Alcon, Fort Worth, TX). Intraoperatively, bottle height, aspiration, and vacuum setting were all lowered to decrease the risk of inadvertent opening of the RK incisions. After cataract removal, the eye was prepared for ORA use by first filling the capsular bag and then the anterior chamber with viscoelastic until a pressure of 20 to 25mm Hg was obtained. The eye was then kept well lubricated, while 2 repeat measurements were taken with the ORA (Fig. 2). The ORA suggested a 17D lens for emmetropia and based on all measurements, an 18D single-piece acrylic lens was placed in the capsular bag. To treat residual macular edema, an intravitreal triamcinolone injection was also given at the end of the procedure. Postoperative day 1, visual acuity was 20/400 due to a residual fibrotic capsule that could not be removed at the time of surgery. Postoperative month 3, after YAG capsulotomy and 2 additional triamcinolone injections, best corrected visual acuity was 20/80 with minimal refractive error (0.50+ 0.50 × 075).

Figure 1.

Posterior subcapsular cataract with radial keratotomy incisions in the cornea.

Figure 2.

Intraoperative aberrometry screen suggesting intraocular lens power of 17.0D with a refractive error of – 0.22.

Case 2

A patient with a history of RK presented to clinic for a cataract evaluation. Past ocular history was significant for a previous gasoline-related trauma to the right eye. She presented with 20/50 vision in the affected eye with a refraction of – 2.25+ 1.00 × 025. On examination, she was noted to have mild dryness of the ocular surface with 8 RK incisions and 2 astigmatic keratotomy incisions. She was also noted to have a 3+ nuclear sclerotic cataract and the retinal examination was within normal limits. The average value obtained from the automated keratometer was 41.25D and that obtained from the Pentacam (Oculus) was 41.5 D. The SRK/T formula from the biometry obtained suggested a 23.5 power acrylic lens for an approximate refractive error of – 0.5D. The decision was made to proceed with surgery with the plan to use the ORA intraoperative aberrometer to titrate the results. The main incision was made between 2 RK incisions to avoid splaying of the wound. However, intraoperatively the RK incision opened during phacoemulsification (Fig. 3). Phacoemulsification was still performed successfully; however, given the anterior chamber instability intraoperative aberrometry could not be accurately performed. Decision was made to proceed with implantation of the lens power as predicted by preoperative methodology; however, upon insertion of the lens a crack was noted just off center (Fig. 4). Given its clearance of the visual axis and the risk associated with explanation of the IOL in an eye with a splayed RK incision and reduced visualization (due to corneal edema), it was decided to leave the IOL in place (Fig. 5). In the immediate postoperative period the patient had corneal edema that ultimately resolved. The final refraction was – 0.25+ 0.50 × 180 with an uncorrected visual acuity of 20/25.

Figure 3.

Radial keratotomy incisions during phacoemulsification.

Figure 4.

Red reflex highlighting mark on intraocular lens at postoperative day 1 visit.

Figure 5.

External slit-lamp photograph with sutured main incision and radial keratotomy wound.

Case 3

A 68-year-old female presented to clinic for cataract surgery evaluation of the left eye. The patient had a history of hyperopic LASIK performed several years prior. On initial examination, her visual acuity was best corrected 20/40 in her left eye with a refraction of +2.50+ 0.50 × 010. On examination she was noted to have a well-healed LASIK flap and a 2+ nuclear sclerotic cataract with cortical changes. On the IOL master (Fig. 6), the patient's keratometry values were 44.29 and 44.94. The SRK/T formula predicted an acrylic lens power of 23.5 for a predicted refractive error of – 0.01. Given the known error of keratometry measurements post-LASIK, the decision was made to place a 24.5 power lens to err on the side of myopia. The patient underwent successful cataract extraction with posterior chamber IOL implantation. At the 1-month postoperative examination, the patient was noted to have significant myopic surprise with a refraction of – 2.00+0.50 × 125. The patient preferred distance vision and thus it was decided to proceed with advanced surface ablation to treat the residual myopia. At the 1-month postoperative period, the patient's unaided visual acuity was 20/25 with a refraction of – 0.50+ 0.25 × 105 and the patient was happy with her refractive outcome.

Figure 6.

Intraocular lens (IOL) master using SRK/T formula for lens power prediction.

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