Supplementary IOLs: Monofocal and Multifocal, Their Applications and Limitations

Supplemental Toric Intraocular Lenses in the Ciliary Sulcus for Correction of Residual Refractive Astigmatism: A Review

PURPOSE

This study conducted a critical review of the peer-reviewed literature on the use of supplemental toric intraocular lenses (STIOL) in the ciliary sulcus to correct residual refractive astigmatism.

METHODS

This review used PubMed as a database from 1 January 2010 to 13 March 2023. According to the inclusion and exclusion criteria defined, 14 articles were selected for the current review.

RESULTS

The data of 155 eyes were analyzed. Most of the studies reviewed had a short follow-up and poor or limited design, including case reports, case series, and retrospective cohorts. The follow-up period ranged from 43 days to 4.5 years. STIOL rotation was the most frequently described complication in the literature, with a mean rotation of 30.48 ± 19.90°. These patients required repositioning in 50 of 155 eyes (32.25%). Moreover, four eyes (2.58%) required scleral fixation sutures and two eyes (1.29%) iris fixation. Other complications were high intraocular pressure (3 eyes, 1.93%), transient corneal edema (2 eyes, 1.29%), corneal decompensation (2 eyes, 1.29%), and pigment dispersion (1 eye, 0.64%). From the total, 57.41% of eyes (89 eyes from 155) achieved within ± 0.50D of target refractive astigmatism. It is important to highlight that at least 52 eyes out of the 155 (33.54%) had an abnormal cornea with irregular astigmatism.

CONCLUSION

STIOL seem to offer good visual and refractive outcomes. However, STIOL showed variable rotational stability, especially in some platforms. Further studies with a more robust design, methodology, and standardized analysis methods are needed to confirm these trends.

Comparison of Primary Duet Lens Procedures: In-The-Bag Monofocal with Sulcus Multifocal, and Standard Single Multifocal Lens for Cataract Surgery

Purpose

To assess the safety and efficacy of primary duet intraocular lens (IOL) procedure using an in-The-bag monofocal IOL and a sulcus-based multifocal reversible platform for cataract surgery. The visual outcomes were compared with a single in-The-bag multifocal IOL.

Patients and Methods

Retrospective cohort study. Consecutive patients who underwent primary duet IOL procedures were compared with consecutive patients who underwent single multifocal IOL surgery. Primary outcomes were uncorrected distance and near visual acuities (UDVA and UNVA), refraction and spherical equivalent data. Secondary outcomes included surgical complications.

Results

The study group consisted of 32 eyes (22 toric IOLs) whilst the control group had 57 eyes (29 toric IOLs). There were no statistically significant differences between the two groups on post-operative 1-month and 1-year UDVA (p=0.1522 and 0.4926, respectively) and UNVA (p=0.1248 and 0.2738, respectively). There were no statistically significant differences in the postoperative 1-month spherical equivalent within ± 0.5 diopter (p=0.1891). Postoperative intraocular pressure spikes were observed on day-1 in both groups, with most returned to their baseline at 1-month and all were normal at 1-year post surgery. There were no statistically significant differences in intraocular pressure between the two groups on day-1, 1-month and 1-year after surgery (p=0.6421). There were no statistically significant differences in the IOL axis deviation from the intended axis in the toric subgroup analysis (p=0.5843).

Conclusion

Primary duet IOL procedure is equally effective and safe in correcting distance and near vision when compared with single multifocal IOL in the capsular bag.

Systematic Review of the Use of Supplemental Multifocal Intraocular Lenses in the Ciliary Sulcus for Presbyopia Correction

PURPOSE

To conduct a critical review of the peer-reviewed literature on the use of supplemental multifocal intraocular lenses in the ciliary sulcus.

METHODS

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement recommendations. According to the inclusion and exclusion criteria defined, 15 articles were selected for the current systematic review. Each of them was analyzed carefully and their risk of bias was assessed with the Quality Assessment Tool for Case Series Studies from the National Heart, Lung, and Blood Institute.

RESULTS

Data of 384 eyes from 227 patients were analyzed. Most of the studies reviewed had a short follow-up and poor or limited design, including case reports, case series, and clinical trials with several gaps in their methodology. Post-operative uncorrected distance and near visual acuity ranged from 20/40 to 20/20 and from 0.4 to 0.02 logMAR, respectively. Pigment dispersion (12 eyes) and deposits (13 eyes) were the most described complication. Dysphotopsia, glare, and halos were the more frequently reported visual disturbances. However, most of the patients reported a high level of satisfaction with their surgery. Most articles reviewed (13 of 15) achieved a risk of bias score between 6 and 8, representing a high level of evidence despite the study design limitations.

CONCLUSIONS

Supplemental multifocal intraocular lenses seem to offer good distance and near visual results, leading to high levels of spectacle independence and patients' satisfaction, with limited complications associated. However, more studies with a more robust design are needed to confirm these trends. [J Refract Surg. 2021;37(12):830-835.].

Reversibility of the duet procedure: Bilateral exchange of a supplementary trifocal sulcus-fixated intraocular lens for correction of a postoperative refractive error

Purpose

We present the case of a 49-year old female who underwent bilateral exchange of a supplementary trifocal sulcus-fixated intraocular lens (IOL) to correct a residual refractive error. Six months beforehand, she had been treated for hyperopia, astigmatism and presbyopia with a duet procedure to create reversible trifocality.

Observations

Refractive lens exchange with combined implantation of a monofocal toric IOL into the capsular bag and a trifocal supplementary IOL into the ciliary sulcus (duet procedure) had been performed in both eyes. Decreased uncorrected distance visual acuity due to the refractive outcome of −0.75 diopter sphere (DS)/-0.25 diopter cylinder (DC)x10° for the right eye and −1.0DS for the left eye as well as the perception of photic phenomena were inacceptable for the patient. In the second operations, we exchanged the supplementary IOLs to correct the residual refractive error and achieve the target refraction of emmetropia. UDVA increased from 0.50 logMAR in both eyes prior to the IOL exchange to −0.22 logMAR in the right eye and −0.20 logMAR in the left eye. Binocular uncorrected near and intermediate visual acuity were −0.10 logMAR and 0.00 logMAR respectively after exchanging the sulcus-fixated supplementary IOLs, allowing for complete spectacle independence.

Conclusions

This case demonstrates one of the most important benefits of the duet procedure: the possibility, if necessary, to easily remove or exchange the supplementary IOL from the ciliary sulcus. The duet procedure offers a safe treatment option in the event of postoperative complications like residual refractive error or intolerance to a multifocal optic.

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.

Spectacle Independence for Pseudophakic Patients - Experience with a Trifocal Supplementary Add-on Intraocular Lens

Purpose

To evaluate the refractive and functional outcomes of the trifocal 1stQ AddOn^® (Medicontur) supplementary intraocular lenses (IOLs) designed for implantation into the ciliary sulcus.

Patients and Methods

The study included 18 eyes of 11 pseudophakic patients with uncomplicated previous implantation of monofocal capsular bag IOLs. These patients had a desire for spectacle independence. Distance, intermediate and near visual acuities were measured, and defocus curves were plotted over a period of 6 months following implantation of the add-on IOLs. Intraocular pressure (IOP), endothelial cell density measurements and biomicroscopic evaluation were also performed.

Results

In this study, 83.3% of eyes had spherical refractions within ±0.5 D from emetropia and 100% of eyes had spherical equivalent refractions that were within ±1.0 D of the target refraction. Visual acuities and defocus curves clearly confirmed trifocal optical performance (UDVA=0.03 ±0.05; UIVA=0.21 ±0.04; UNVA=0.12 ±0.04 logMAR; expressed as mean ±SD). Depth of focus showed identical results (DOF=0.486 D) compared to a trifocal capsular bag IOL, while the defocus curve was found to be superior in the intermediate and near ranges when compared to a trifocal capsular bag IOL. All patients achieved spectacle independence at all distances. All add-on IOLs were well positioned in the ciliary sulcus. No negative changes were noted in connection with endothelial cell counts, IOPs, the angle structure during surgery and during the follow-up period.

Conclusion

The supplementary trifocal add-on IOL seems to be a safe, efficient and stable solution for achieving spectacle independence in pseudophakic patients with monofocal primary IOLs.