Secondary Intraocular Lens Implantation After Simultaneous Penetrating Keratoplasty and Cataract Extraction for Coexisting Corneal and Lens Opacities

Management of post-keratoplasty ametropia

Even after a successful corneal transplant, patients experience severe refractive errors, impeding their rehabilitation and satisfaction. Refractive errors can be caused by recipient pathology and corneal thickness, as well as intraoperative factors such as donor-host discrepancy, recipient's eccentric trephination, vitreous length, wound apposition, technique of suturing, and suture material. Also, wound healing and the interim between keratoplasty and suture removal contribute to astigmatism. Lamellar keratoplasty outperforms penetrating keratoplasty in terms of endothelial cell loss and endothelial graft rejection, yet the risk of developing refractive errors is comparable. Nonsurgical interventions such as spectacles and lenses fail to provide desirable vision in cases with high astigmatism and corneal irregularity. When these limitations are encountered, surgical interventions including incisional keratotomy, wedge resection, laser refractive surgeries, intracorneal segments, and intraocular lens implantation are employed. However, occasionally, none of these approaches deliver the desired effects, leading to the need for a repeat keratoplasty.

Long-Term Results and Refractive Error After Cataract Surgery With a Scleral Incision in Eyes With Deep Anterior Lamellar Keratoplasty

PURPOSE

Phacoemulsification in eyes with deep anterior lamellar keratoplasty (DALK) is associated with possible decreased graft survival and difficult IOL power calculation. We assessed cataract surgery in eyes with previous DALK.

METHODS

Thirty-three consecutive eyes with DALK and further phacoemulsification with scleral incision were included in this retrospective study. At each postoperative visit, eyes were assessed with manifest refraction, optical coherence tomography, specular corneal topography, and noncontact wide-field specular microscopy.

RESULTS

The average postkeratoplasty follow-up time was 102 months [95%-CI, (85-119)]. Cataract surgery was performed on average 43 months (30-56) after DALK. The average postphacoemulsification follow-up time was 58 months [42-74]. All grafts remained clear during follow-up. The best spectacle-corrected logarithm of the minimum angle of resolution visual acuity improved by 2.5 lines [1.8-3.1] on average after cataract surgery from 0.58 (20/77) to 0.34 (20/44) (P < 0.001). The spherical equivalent and intraocular pressure significantly improved from -4.1 D to -1.7 D and from 15.9 to 14.0 mm Hg, respectively. The corneal central thickness was not significantly modified, and the endothelial density decreased by 5.3% from 2081 to 1970 cells/mm2 (P = 0.003). The minimal difference between the achieved and predicted spherical equivalents [-0.05 D, (-2.33; +2.21)] was obtained with the Hoffer Q formula using the IOLMaster axial length and the Orbscan keratometry.

CONCLUSIONS

Patients with DALK who underwent phacoemulsification with a scleral incision had a satisfying residual refractive error, very high graft survival, and very few complications. The Hoffer Q formula with the IOLMaster axial length and the specular corneal topography keratometry seems to be the most accurate for IOL calculation.