Extended depth of focus lens implantation after radial keratotomy

Cataract surgery after corneal refractive surgery: preoperative considerations and management

PURPOSE OF REVIEW

Corneal refractive surgery (CRS) is one of the most popular eye procedures, with more than 40 million cases performed globally. As CRS-treated patients age and develop cataract, the number of cases that require additional preoperative considerations and management will increase around the world. Thus, we provide an up-to-date, concise overview of the considerations and outcomes of cataract surgery in eyes with previous CRS, including surface ablation, laser in-situ keratomileusis (LASIK), and small-incision lenticule extraction (SMILE).

RECENT FINDINGS

Challenges associated with accurate biometry in eyes with CRS have been mitigated recently through total keratometry, ray tracing, intraoperative aberrometry, and machine learning assisted intraocular lens (IOL) power calculation formulas to improve prediction. Emerging studies have highlighted the superior performance of ray tracing and/or total keratometry-based formulas for IOL power calculation in eyes with previous SMILE. Dry eye remains a common side effect after cataract surgery, especially in eyes with CRS, though the risk appears to be lower after SMILE than LASIK (in the short-term). Recent presbyopia-correcting IOL designs such as extended depth of focus (EDOF) IOLs may be suitable in carefully selected eyes with previous CRS.

SUMMARY

Ophthalmologists will increasingly face challenges associated with the surgical management of cataract in patients with prior CRS. Careful preoperative assessment of the ocular surface, appropriate use of IOL power calculation formulas, and strategies for presbyopia correction are key to achieve good clinical and refractive outcomes and patient satisfaction. Recent advances in CRS techniques, such as SMILE, may pose new challenges for such eyes in the future.

Clinical Outcomes with Extended Depth of Focus Intraocular Lenses in Cases in Which Multifocal Lenses Are Not Primarily Recommended

Purpose

The purpose of the study is to evaluate the visual and patient-reported outcomes of patients undergoing cataract surgery with implantation of an extended depth of focus (EDOF) intraocular lens (IOL) who were not primarily good candidates for multifocal IOL implantation.

Methods

Retrospective analysis of data from 30 eyes (23 patients) undergoing cataract surgery with implantation of one of two EDOF IOLs (follow-up: 37.9 ± 16.2 months) and prospective observational study including 106 eyes (78 patients) implanted with one of 6 different EDOF models (follow-up: 8.0 ± 7.7 months). Patients recruited had one of the following conditions: monofocal IOL implanted in the fellow eye, previous corneal refractive surgery, mild and nonprogressive maculopathy or glaucoma, age > 75 years, amblyopia, or previous vitrectomy.

Results

In the retrospective phase, significant improvements were found in uncorrected distance (UDVA), corrected distance (CDVA), and corrected near visual acuity (CNVA) (p ≤ 0.013), with a nonsignificant trend to improvement in uncorrected near visual acuity (UNVA). A total of 90% of patients were completely to moderately satisfied with the outcome achieved. In the prospective phase, significant improvements were found in UDVA, CDVA, UNVA, and CNVA (p ≤ 0.032), with a total of 85.5% of patients being completely to moderately satisfied (dissatisfaction 3.3%). In both phases, extreme difficulties were only reported by a limited percentage of patients for performing some near vision activities.

Conclusions

EDOF IOLs seem to be a viable option for providing an efficient visual rehabilitation with good levels of patient satisfaction and spectacle independence associated in patients that are not primarily good candidates for multifocal IOL implantation.

Clinical Outcomes of a Non-Diffractive Extended Depth-of-Focus IOL in Eyes with Mild Glaucoma

Purpose

To evaluate the clinical outcomes of a non-diffractive, wavefront-shaping extended depth-of-focus (EDOF) intraocular lens (IOL) in eyes with mild open-angle glaucoma (OAG).

Setting

Private practice; Sioux Falls, South Dakota.

Design

Prospective, open-label, interventional study.

Methods

In total, 52 eyes of 26 patients with mild OAG were enrolled and completed the study. All patients were bilaterally implanted with a non-diffractive, wavefront-shaping EDOF IOL. Seventy-seven percent of the patients were implanted with a trabecular microbypass stent at the time of surgery. Primary outcome measures included binocular corrected and uncorrected distance visual acuity (CDVA and UDVA), uncorrected intermediate and near visual acuity (UIVA and UNVA) and contrast sensitivity as measured by a Pelli-Robson chart. A subjective questionnaire was also administered to patients.

Results

At 4 months postoperative, the mean binocular UDVA and CDVA was 0.03 ± 0.12 and -0.06 ± 0.07, respectively. The mean UIVA and UNVA were 0.18 ± 0.12 and 0.31 ± 0.18, respectively. Eighty-five percent of the subjects achieved ≥20/25 UDVA and 77% of the subjects achieved ≥20/32 UIVA at 4 months postoperative. The mean binocular mesopic contrast sensitivity was 1.76 ± 0.16 at a spatial frequency of 1 cycle-per-degree (cpd). Eighty-five percent of the subjects reported they would choose the same lens and 1 subject reported they would choose a different IOL if it meant reduced spectacle independence.

Conclusion

The non-diffractive, wavefront-shaping EDOF IOL can be safely implanted in eyes with mild, pre-perimetric open-angle glaucoma with favorable uncorrected distance and intermediate visual acuity. The contrast sensitivity measurements were favorable and the subjective questionnaire revealed satisfactory spectacle independence and patient satisfaction.

Visual Outcomes after Implantation of Lucidis EDOF IOL

Purpose. To evaluate the visual performance and clinical outcomes after implantation of Lucidis EDOF IOL following cataract surgery. Design. In this retrospective study, medical records from all enrolled patients were analyzed, and the following information was extracted retrospectively over 3 months following surgery. Materials and Methods. We reviewed retrospectively 181 eyes of 98 patients, who underwent cataract surgery with Lucidis extended depth of focus IOL. Results. 44 patients were males (45%) and 54 were females (55%). The average age of the study population was 68 ± 11 years. The mean preoperative BCVA (logMAR) was 0.19 ± 0.18. The mean root mean square (RMS) high order aberration (HOA) was 0.18 ± 0.1. Monocular BCVA results were 0.02 ± 0.04 (logMAR) and 0.028 ± 0.04 (logMAR) 1 month and 3 months postoperatively, respectively. Between the baseline and 1-month measures, monocular distance BCVA improved by an average of 0.17 ± 0.14 logMAR ( $p$  = 0.0001). Between the baseline and 3-month postoperative measures, monocular distance BCVA improved by an average of 0.16 ± 0.13 logMAR ( $p$  = 0.0001). Monocular UDVA 1 and 3 months postoperatively was 0.08 ± 0.1 logMAR and 0.067 ± 0.08 logMAR, respectively. 1-Month postoperative binocular UDVA was 0.036 ± 0.05 logMAR, binocular UIVA was 0.1 ± 0.08 logMAR, and binocular UNVA was 0.12 ± 0.14 logMAR. 3-Month postoperative binocular UDVA was 0.038 ± 0.05 logMAR, binocular UIVA was 0.09 ± 0.1 logMAR, and binocular UNVA was 0.16 ± 0.14 logMAR. Conclusions. Lucidis EDOF IOL achieves good visual performances in all distances.

Cataract Surgery after Radial Keratotomy with Non-Diffractive Extended Depth of Focus Lens Implantation

Radial keratotomy was a popular surgical procedure used to treat myopia. Patients who underwent radial keratotomy several years ago, are currently reporting to the ophthalmologist due to worsening of vision associated with age-related cataracts. In this case report we present a case of a 60-year-old woman who underwent radial keratotomy with 16 incisions in the right eye and 12 incisions in the left eye. The patient reported to an ophthalmologist due to a deterioration of vision caused by a cataract. We described, in detail, the difficulties encountered during the diagnostic procedures, differences in the calculation of intraocular lens, and intraoperative difficulties as compared to patients who had not undergone radial keratotomy. We also present the obtained postoperative results.

Accuracy and safety of partial thickness femtosecond laser radial and arcuate keratotomy incisions in porcine eyes

Background

To evaluate the accuracy and safety of micro radial and arcuate keratotomy incisions constructed by a femtosecond laser system with a curved contact patient interface in porcine eyes.

Methods

Partial thickness micro radial and arcuate keratotomy incisions were constructed in porcine eyes with a femtosecond laser system and evaluated for precision of depth, quality, and consistency. Optical coherence tomography was used to determine the accuracy and precision of incision depth. Corneal endothelial safety was assessed by a fluorescent live/dead cell viability assay to demonstrate laser-induced endothelial cell loss. Quality was evaluated by ease of opening and examination of interfaces.

Results

In two micro radial incision groups, intended incision depths of 50% and 80% resulted in mean achieved depths of 50.01% and 77.69%, respectively. In three arcuate incision groups, intended incision depths of 80%, 600 μm or 100 μm residual uncut bed thickness resulted in mean achieved depths of 80.16%, 603.03 μm and residual bed of 115 μm, respectively. No loss of endothelial cell density occurred when the residual corneal bed was maintained at a minimum of 85–116 µm. The incisions were easy to open, and interfaces were smooth.

Conclusions

A femtosecond laser system with curved contact interface created precise and reproducible micro radial and arcuate keratotomy incisions. Accuracy and precision of the incision depth and preservation of endothelial cell density demonstrated the effectiveness and safety of the system.

Matching the Patient to the Intraocular Lens: Preoperative Considerations to Optimize Surgical Outcomes

The intraocular lens (IOL) selection process for patients requires a complex and objective assessment of patient-specific ocular characteristics, including the quality and quantity of corneal astigmatism, health of the ocular surface, and other ocular comorbidities. Potential issues that could be considered complications after surgery, including dry eye disease, anterior or epithelial basement membrane dystrophy, Salzmann nodular degeneration, and pterygium, should be addressed proactively. Aspheric IOLs are designed to eliminate the positive spherical aberration added by traditional IOLs to the pseudophakic visual axis. Spherical aberration may be a consideration with patient selection. Patient desire for increased spectacle independence after surgery is one of the main drivers for the development of multifocal IOLs and extended depth-of-focus (EDOF) IOLs. However, no one single multifocal or EDOF IOL suits all patients' needs. The wide variety of multifocal and EDOF IOLs, their optics, and their respective impact on patient quality of vision have to be understood fully to choose the appropriate IOL for each individual, and surgery has to be customized. Patients who have undergone previous LASIK or who have radial keratotomy and ocular pathologic features, including glaucoma, age-related macular degeneration, and epiretinal membrane, require specific considerations for IOL selection. Subjectively, patient-centered considerations, including visual goals, lifestyle, personality, profession, and hobbies, are key elements for the surgeon to assess and factor into an IOL recommendation. This holistic approach will help surgeons to achieve optimal surgical outcomes and to meet (and exceed) the high expectations of patients.

A pinhole implant to correct postoperative residual refractive error in an RK cataract patient

Purpose

To report the clinical outcomes after implantation of a pinhole supplementary implant (Xtrafocus, Morcher GmbH, Stuttgart, Germany) to correct fluctuating residual refraction after cataract surgery in a patient with a history of radial keratotomy (RK).

Observations

A 62-year-old patient who had radial keratotomy 22 years earlier, underwent uneventful bilateral cataract surgery using the ASCRS IOL-Calculator for post-RK. Postoperatively, the patient showed fluctuating subjective manifest refraction (MR) on both eyes. To correct the large fluctuating residual refractive error and subjectively worse visual acuity, Xtrafocus IOL was implanted in the right eye. One week later, the uncorrected distance visual acuity (UDVA) was already 0.1 logMAR and the patient stated to have stable vision. Three months after Xtrafocus implantation, the UDVA was −0.04 logMAR which did not improve with MR and the patient expressed high satisfaction, good subjective binocular contrast sensitivity, comparable visual field outcomes, and an elongated depth of focus.

Conclusions and Importance

The pinhole sulcus implant not only helped eliminate the fluctuation in residual refraction after cataract surgery, but also provided an elongated depth of focus without greatly affecting the visual field. The supplementary implantation of the Xtrafocus lens can offer an effective option for the treatment of instable refractive errors after cataract surgery in patients with a history of corneal surgery.