Arecent review of keratorefractive and intraocular approaches to managing refractive error after cataract surgery pointed out that laser surgery yields more effective and predictable outcomes than intraocular lens (IOL) surgery.1 LASIK and photorefractive keratectomy (PRK) are reasonable approaches for the correction of astigmatic and small spherical refractive errors; however, piggyback IOLs implanted in the sulcus may represent a better solution for larger spherical and cylindrical refractive errors. Laser surgery has proved to be useful, safe, and predictable, but is not recommended in some cases (eg, in eyes with thin or irregular corneas or in severe dry eye).2 Piggyback IOLs can achieve excellent results and likely represent the best choice for correction of residual spherical ametropia in eyes with a history of prior radial keratotomy and eyes with ocular surface disease or suspicious corneal topography that are not good candidates for LASIK or PRK. Piggyback IOLs also appear to be the better option relative to IOL exchange to minimize trauma and reduce complications, and to improve the accuracy of IOL power calculation.1,3–7
The use of piggyback IOLs was originally described to provide adequate power in high ametropia8 and has more recently been suggested for the correction of postoperative residual refractive error.4 Beginning in 2010, ciliary sulcus lenses such as the Sulcoflex,9–18 Add-on HumanOptics,18–23 or A4 AddOn24 have shown good outcomes for the correction of pseudophakic refractive errors. In 2001, Chiou et al.25 were the first to propose off-label use of a Visian Implantable Collamer Lens (ICL) (STAAR Surgical, Inc., Monrovia, CA), which is specifically designed to be implanted in the ciliary sulcus to manage pseudophakic ametropia. The ICL, which was developed to correct myopic, hyperopic, and astigmatic errors in phakic eyes, and has been shown to provide excellent visual outcomes,26,27 is equally applicable to the correction of residual refractive error in pseudophakic eyes. A few small case reports28,29 and larger samples,30 including children,31 have proposed the use of the ICL to manage residual refractive errors with good visual and refractive outcomes. More studies with larger sample sizes, including eyes with a variety of clinical conditions, are necessary to provide surgeons with sufficient clinical data to evaluate the safety and effectiveness of the ICL for the correction of residual refractive error in pseudophakia.
The current study assessed the visual outcomes, predictability, and safety of the ICL for the management of residual pseudophakic refractive error in eyes with previous corneal surgery.
Patients and Methods
This was a retrospective observational study involving 49 eyes of 40 patients who underwent implantation of a myopic, hyperopic, or toric ICL (STAAR Surgical, Inc.) at the Fernández-Vega Ophthalmological Institute, Oviedo, Spain, from November 2005 to November 2017.
Inclusion criteria specified pseudophakic eyes with refractive error in the range correctable with the ICL, age older than 20 years, corrected distance visual acuity (CDVA) of 20/100 or better, stable refraction, and a clear central cornea. Exclusion criteria specified anterior chamber depth from the endothelium less than 2.8 mm, central corneal endothelial cell density (ECD) less than 750 cell/mm2, history of glaucoma, amblyopia, retinal detachment, diabetic retinopathy, macular degeneration, neuro-ophthalmic diseases, and uveitis. A written informed consent was obtained from all patients after the nature and possible consequences of the study were explained fully in accordance with the tenets of the Declaration of Helsinki.
Before surgery, patients had a full ophthalmologic examination including uncorrected distance visual acuity (UDVA) and CDVA (85 cd/m2), refraction, slit-lamp biomicroscopic evaluation, intraocular pressure (IOP) measurement, corneal topography using the Orbscan II (Bausch & Lomb, Rochester, NY), ECD (SP 3000P; Topcon Europe Medical, Capelle aan den IJssel, Netherlands), and dilated binocular indirect ophthalmoscopy. All eyes demonstrated residual refractive error after phacoemulsification and IOL implantation with a spectrum of underlying clinical conditions, including virgin cornea, history of excimer laser (LASIK or PRK), radial keratotomy, intrastromal corneal ring segments (ICRS) implantation, penetrating keratoplasty, or deep anterior lamellar keratoplasty (DALK).
The ICL is made of collamer, a proprietary hydroxyethyl methacrylate (HEMA)/porcine-collagen based bio-compatible polymer material and an ultraviolet-absorbing chromophore. It has a refractive index of 1.442 at room temperature in balanced salt solution. The ICL is designed as a plate haptic lens with a central convex-concave optical zone and incorporates a forward vault to minimize contact of the ICL with the central anterior capsule of the crystalline lens. ICL models implanted in this study include ICHV3, ICMV4, TICM, VICH, VICMO, VICM5, VTICMO, and VTICM5. The lengths of the ICLs implanted were 11.5, 11.6, 12.00, 12.1, 12.5, 12.6, and 13.2 mm, and the spherical power ranged from +9.00 to −12.00 diopters (D), with toric power up to +6.00 D at the lens plane. ICLs incorporating a central port (“hole ICL”) do not require the construction of an iridotomy or iridectomy, as do ICLs without the port (“non-hole ICL”).
The power of the ICL was calculated using the software provided by STAAR Surgical, Inc., which uses a modified vertex formula. The targeted refraction was emmetropia in all cases. The size of the ICL was also determined based the manufacturer's instructions using the horizontal white-to-white distance and anterior chamber depth measured with Orbscan II (Bausch & Lomb). Nd:YAG laser iridotomy was performed preoperatively or a surgical iridectomy was performed intraoperatively for patients implanted with non-hole ICLs. All surgeries were performed by the same experienced surgeon (JFA) through a 3- to 3.4-mm clear corneal incision on the keratometric steep meridian (3 mm for 0.75 D; 3.2 mm for 1.00 D; 3.4 mm for 1.25 D), using peribulbar anesthesia. Thirty minutes before surgery, mydriatic eye drops were applied. Five minutes before surgery, povidone-iodine 5% was applied. The anterior chamber was filled with sodium hyaluronate 1%, which was completely removed following ICL implantation. Tobramycin and dexamethasone 0.1% eye drops were used four times a day for 10 days, after which diclofenac sodium eye drops were started four times a day for 2 weeks.
Postoperative examinations included UDVA, CDVA, manifest refraction, slit-lamp biomicroscopy, and vault measured by anterior segment optical coherence tomography. The vault between the pseudophakic IOL and the ICL was measured perpendicular to the lens apex.
Assessment of outcomes was based on preoperative versus postoperative CDVA and UDVA values and the achieved versus the expected postoperative refractive outcomes (predictability). The efficacy index (defined as the ratio between the postoperative UDVA and the preoperative CDVA) and the safety index (defined as the ratio between the postoperative CDVA and the pre-operative CDVA) were calculated based on decimal visual acuity values. Manifest refractions were recorded in conventional script notation (sphere, cylinder, axis) and then combined to obtain the spherical equivalent.
A total of 49 eyes of 40 patients with a mean age at ICL surgery of 59.34 ± 11.44 years (range: 31 to 85 years) were enrolled in our study. Of the 40 patients enrolled, 22 (55%) were female. The mean time between cataract surgery and piggyback ICL implantation was 53.17 ± 67.05 months (range: 4.6 to 252.8 months). Mean follow-up after piggyback ICL implantation was 24.10 ± 25.38 months (range: 1 to 88 months). Of the 49 included eyes, 6 had residual refractive error after phacoemulsification with no corneal pathology or surgical history (virgin cornea), 12 were LASIK or PRK, 8 had radial keratotomy, 5 had ICRS implantation, 11 had penetrating keratoplasty, and 7 had DALK. Specifically, mean follow-up after piggyback ICL implantation was 42.35 ± 41.38 months (range: 3 to 88 months) for virgin corneas, 19.02 ± 22.98 months (range: 2 to 84 months) for laser treatment, 16.06 ± 9.53 months (range: 8 to 33 months) for radial keratotomy, 30.94 ± 23.73 months (range: 11 to 69 months) for ICRS implantation, 29.29 ± 28.96 months (range: 5 to 83 months) for penetrating keratoplasty, and 13.32 ± 13.57 months (range: 1 to 39 months) for DALK.
The primary IOL implanted was monofocal in 29 eyes and multifocal in 20 eyes; all IOLs were implanted in the capsular bag. The IOLs included the following: AcrySof SN60WF (n = 8; Alcon Laboratories, Inc., Fort Worth, TX), Symfony ZXR00 (n = 6; Johnson & Johnson Surgical Vision, Santa Ana, CA), AcrySof MN60MA (n = 5; Alcon Laboratories, Inc.), AcrySof ReSTOR SN60D3 +4.00D (n = 4; Alcon Laboratories, Inc.), AcrySof SN60AT (n = 3; Alcon Laboratories, Inc.), AcrySof ReSTOR IQ SN6AD1 +3.00 (n = 2; Alcon Laboratories, Inc.), AcrySof ReSTOR IQ +2.50 (n = 2; Alcon Laboratories, Inc.), AT Lisa 839MP Trifocal (n = 2; Carl Zeiss Meditec, Jena, Germany), FineVision POD-F Trifocal (n = 2; Physiol, Liège, Belgium), Acri.Tec 737 (n = 1; Acri. Tec GmbH, Berlin, Germany) AMO Array SA40N (n = 1; Allergan, Irvine, CA), and unknown monofocal (n = 13). Eighteen eyes had a history of Nd:YAG posterior capsulotomy. Table 1 provides the preoperative characteristics of eyes stratified by clinical condition. Figure A (available in the online version of this article) shows several examples of pseudophakic eyes implanted with the ICL.
Preoperative Characteristics of Eyes Stratified by Corneal Clinical Conditions
Example of different eyes implanted with an Implantable Collamer Lens (ICL) (STAAR Surgical, Inc., Monrovia, CA). (A) Virgin cornea group, (B) excimer laser group, (C) radial keratotomy group, (D) intrastromal corneal ring segments group, (E) penetrating keratoplasty group, and (F) deep anterior lamellar keratoplasty group.
Standard graphs for reporting refractive and visual acuity outcomes were constructed separately for the different clinical conditions. Figure 1 provides the cumulative preoperative Snellen CDVA and postoperative Snellen UDVA. Figure 2 shows the change in Snellen lines of CDVA. Figure 3 provides the attempted versus achieved spherical equivalent and Figure 4 provides the spherical equivalent refractive accuracy.
Cumulative Snellen preoperative corrected distance visual acuity (CDVA) and postoperative uncorrected distance visual acuity (UDVA) for the virgin cornea, excimer laser, radial keratotomy (RK), intrastromal corneal ring segments (ICRS), penetrating keratoplasty (PK), and deep anterior lamellar keratoplasty (DALK) groups.
Change in Snellen lines of corrected distance visual acuity (CDVA) for the virgin cornea, excimer laser, radial keratotomy (RK), intrastromal corneal ring segments (ICRS), penetrating keratoplasty (PK), and deep anterior lamellar keratoplasty (DALK) groups.
Attempted versus achieved spherical equivalent (SE) for the virgin cornea, excimer laser, radial keratotomy (RK), intrastromal corneal ring segments (ICRS), penetrating keratoplasty (PK), and deep anterior lamellar keratoplasty (DALK) groups. D = diopters
Spherical equivalent (SE) refractive accuracy for the virgin cornea, excimer laser, radial keratotomy (RK), intrastromal corneal ring segments (ICRS), penetrating keratoplasty (PK), and deep anterior lamellar keratoplasty (DALK) groups. D = diopters
No intraoperative or postoperative complications occurred; there were no events of pupillary block, elevated intraocular pressure requiring treatment, pigment dispersion, loss of vision due to corneal edema, secondary surgical intervention (no rotation of toric lenses requiring repositioning), or interlenticular opacification reported throughout the follow-up period. Table 2 shows the efficacy and safety indices of the different groups of eyes studied. In addition, mean ± standard deviation and range of postoperative decimal UDVA and CDVA are shown. ECD was 2,138.2 ± 711, 1,949.4 ± 486, 2,192.8 ± 823, 1,781.5 ± 695, 1,460.8 ± 960, and 1,561.1 ± 616 mm2 for the virgin cornea, excimer laser, radial keratotomy, ICRS, penetrating keratoplasty, and DALK groups, respectively. Means ± standard deviation vault values were 1,438.0 ± 356.4 (range: 882 to 1,840), 1,393.2 ± 318.6 (range: 872 to 1,842), and 1,633.2 ± 259.8 (range: 1,378 to 2,050) μm, for the virgin cornea, excimer laser, and radial keratotomy groups, respectively. Means ± standard deviation for ICRS, penetrating keratoplasty, and DALK groups were 1,486.0 ± 80.4 (range: 1,610 to 1,390), 1,335.9 ± 337.6 (range: 880 to 1,830), and 1,401.0 ± 293.6 (range: 920 to 1,650) μm, respectively.
Visual Acuity Outcomes of Eyes Stratified by Corneal Clinical Conditions
A variety of cornea- and lens-based surgical approaches for the correction of residual pseudophakic ametropia have been proposed. Advantages and drawbacks of the different techniques have been reviewed and discussed in the literature.1 In those cases where an excimer laser is contraindicated, a lens-based approach is required. Of lens-based options, IOL exchange can be challenging due to capsular fibrosis and adhesion of the primary IOL to the capsule. IOL exchange requires additional manipulation compared to placing a piggyback IOL, and increases the risk of complications such as zonular damage, vitreous loss, cystoid macular edema, retinal tears, retinal detachment, corneal endothelial damage, and capsule rupture.1,3 In addition, IOL power calculation is more complicated and less accurate in an exchange than with a piggyback IOL.4 Piggyback power IOL calculation is relatively straightforward and is primarily based on the subjective manifest refraction.32
Although the use of a piggyback IOL reduces the risk of complications compared to IOL exchange,3 IOLs originally designed to be implanted in the capsular bag may not be appropriate for the ciliary sulcus, and may predispose to complications such as pigment dispersion, iris transillumination defects, elevated IOP, hyphema, and cystoid macular edema.33,34 It is reasonable to expect that a lens specifically designed for ciliary sulcus implantation, such as the ICL, may minimize the overall incidence of complications.25,30 Several authors have suggested that placing piggyback IOLs in the sulcus prevents interlenticular opacification and the associated hyperopic shift,5–7 and no cases of interlenticular opacification have been reported with the ICL.
The use of ciliary sulcus–based IOLs for refractive error correction in pseudophakic eyes can be a good solution in many cases. The use of piggyback lenses designed to be implanted in the sulcus avoids the limitations of excimer laser procedures due to corneal thickness or irregular corneal topography. In addition, piggyback IOLs provide a wide range of refractive correction, both spherical and cylindrical, with straightforward IOL power calculations in a completely reversible procedure.
Among the different ciliary sulcus lenses commercially available today, the ICL has two important advantages: it has a wider refractive range and it is available in multiple sizes. These advantages, and the long-term studies supporting good outcomes in phakic eyes,26,27 make the ICL an excellent option for correction of residual refractive error in pseudophakic eyes. Preliminary studies25,28–31 with multiple ICL models in a spectrum of clinical conditions support this hypothesis. This study was undertaken to increase the body of evidence for ICL implantation in pseudophakia.
The results of this retrospective study of 49 eyes of 40 patients who underwent ICL implantation to correct residual ametropia after cataract surgery show good outcomes in several different clinical conditions. We observed better outcomes in terms of refractive accuracy for the virgin cornea, excimer laser, and radial keratotomy groups compared to the ICRS, penetrating keratoplasty, and DALK groups. This result may be expected, considering the pathophysiologic status of the cornea in the latter, more severely diseased groups. In relation to the safety index, all groups showed values larger than 1.0 and no eye lost one or more lines of CDVA.
Results showed good refractive predictability. The virgin cornea, excimer laser, and radial keratotomy groups showed better predictability and accuracy than the ICRS, penetrating keratoplasty, and DALK groups, with spherical equivalent in 96.2% of eyes within ±1.00 D. The ICRS, penetrating keratoplasty, and DALK groups showed approxiamtely 50% of eyes had spherical equivalent within ±1.00 D. We observed that the predictability and accuracy is lower for those groups with more severe corneal disease.
Table A (available in the online version of this article) provides a summary of studies with ciliary sulcus lenses implanted in pseudophakic eyes, including Sulcoflex, HumanOptics, A4 AddOn, and ICL. A total of 10 clinical studies have been published with the Sulcoflex lens, from case reports to larger samples with spherical, toric, and multifocal platforms. The most common adverse event reported in these studies has been increased IOP9,11,12 and mild pigment dispersion.18
Clinical Studies of Ciliary Sulcus Intraocular Lenses in Pseudophakic Eyes
The HumanOptics lens was evaluated in 5 studies with the spherical, toric, and multifocal platforms. Pigment dispersion and corneal edema requiring keratoplasty have been reported.18,20,23 Only one study has been published with the A4 AddOn lens24 with the spherical and toric platforms, and reported 1 eye requiring toric lens realignment.
Five studies have evaluated correction of pseudophakic refractive error with the ICL. The first study was reported by Chiou et al.25 in 2001 based on 2 eyes of 2 patients after unilateral phacoemulsification and IOL implantation. Postoperatively, UDVA improved from 20/400 to 20/30 in the first patient and from 20/200 to 20/40 in the second patient. There were no complications.
Hsuan et al.28 used the ICL in 6 eyes for myopic and hyperopic correction in patients with anisometropia (from +13.00 to −7.50 D ICL power). Anisometropia was reduced to asymptomatic levels (mean reduction of 3.15 D), and CDVA was unchanged or improved in all eyes except for 1 patient with preexisting macular degeneration. No adverse events were reported during the follow-up of less than 1 year. Our results agree with those reported by Chiou et al.25 and Hsuan et al.28; we also found no loss of CDVA. Note that Chiou et al.25 reported 1 eye with previous radial keratotomy, and our series of 8 eyes after radial keratotomy demonstrated a safety index of 1.11.
Kojima et al.29 evaluated the feasibility of the toric ICL for correction of pseudophakic refractive error in 8 eyes with 6 months of follow-up. They found an improvement in both UDVA and CDVA, with a safety index of 1.14 and an efficacy index of 0.86. No eye lost more than one line of Snellen CDVA. In relation to predictability, all eyes (100%) were corrected within ±0.50 D of attempted spherical equivalent and 62.5% (5 eyes) were within ±0.50 D of astigmatism (1.00 D in 87.5% [7 eyes]). The authors reported that 6 eyes showed a high vault (defined: > 150% the corneal thickness) and 2 showed a moderate vault (defined: ≥ 50% and ≤ 150% the corneal thickness), although it must be recognized that these definitions of moderate and high vault were derived from phakic eyes and may not apply in pseudophakic eyes, in which the anterior chamber depth is much greater. In cases with high vault, the angle was open and no abnormalities were apparent when examined on gonioscopy. They reported one case of pupillary block 1 day after the surgery that resolved with Nd:YAG laser iridotomy. A reduction of 4.78% in ECD was reported 6 months postoperatively (mean change from 2,809.0 to 2,674.6 cells/mm2). They concluded that the use of a toric ICL in these cases is an effective and predictable solution for refractive error correction. Although our study did not include virgin eyes requiring a toric ICL, the safety indices we found were similar to those reported by Kojima et al. (1.10 to 1.23).29
The study with the largest sample to date was reported by Eissa et al.,30 who examined 18 eyes with the toric V4c and hyperopic V4b models with 18 months of follow-up. No peripheral iridotomy was required in those eyes implanted with the V4c model, which includes the central port. Some eyes showed severe dry eye, thin cornea, previous laser ablation, or atypical topography. Preoperative mean spherical equivalent changed from −3.08 ± 2.37 to −0.44 ± 0.23 D postoperatively. UDVA improved in all eyes and CDVA improved in 13 eyes by two or more lines. A reduction of 3.19% in ECD was reported 12 months postoperatively (mean change from 2,878.57 to 2,725.71 cells/mm2, P < .01). These authors reported 2 eyes with acute IOP elevation with anterior uveitis, controlled by topical steroids and a beta-blocker, and 1 eye with high vault (1 week, 855 μm), which was reduced by rotation of the ICL to a vertical position in the sulcus (1 month, 689 μm). No cases of interlenticular opacification were reported. As with the previous authors, Eissa et al.30 concluded that sulcus implantation of the ICL lens was safe and predictable. Our results agree with this study; specifically, a high percentage of eyes gained one or more lines of visual acuity in our series.
Another study by Eissa31 included 14 eyes of pediatric patients 5 to 9 years old with anisometropic amblyopia. He found an improvement in UDVA in all cases; CDVA improved two to four lines in 11 eyes and did not change in 3 eyes. Manifest refractive spherical equivalent was reduced significantly from −5.23 ± 1.13 to −0.30 ± 0.50 D at 24 months postoperatively. A reduction of 8.09% in ECD was reported 12 months postoperatively (mean change from 2,961.57 to 2,721.71 cells/mm2, P < .001). The author reported 2 eyes with acute IOP elevation 1 day after the surgery due to retained ophthalmic viscosurgical device that was controlled by topical beta-blockers for 3 days, and 6 eyes with acute anterior uveitis and pigment deposition on the ICL that were controlled by topical steroids for 3 days. Eissa31 concluded that this technique to correct unilateral pseudophakic anisometropic amblyopia in children was safe, efficient, predictable, and well tolerated.
Advantages of using piggyback IOLs for enhancement in all cases includes fast rehabilitation, good predictability, and avoiding the limitations of excimer laser procedures.35 The use of spherical, aspheric, toric, or multifocal IOLs enables correction of spherical and astigmatic errors, as well as presbyopia. Piggyback IOLs have been used to correct postoperative residual refractive error, whereas the use of a piggyback multifocal IOL can provide patients with good visual acuity not only at distance but also at near. Taking into account the outcomes reported in the literature for in-the bag36–40 and ciliary sulcus presbyopia-correcting10,17,18,22,23 lenses, new models of the ICL with the capability to provide pseudoaccommodation may be an interesting option for surgeons to treat patients with both distance and near visual needs.
Surgeons should always remain aware of potential complications. Although the anterior chamber depth is greater and the anterior chamber angle is generally more widely open in pseudophakic eyes, the possibility of pupillary block cannot be ignored. Because of this, it is recommended that peripheral iridectomy or laser iridotomy be performed in eyes implanted with the non-hole ICL model. In contrast, the hole ICL model, with the Aquaport system, does not require preoperative laser iridotomy or surgical iridectomy. There were no cases of pupillary block in our series.
Our study supports the safety and effectiveness of the ICL to manage residual refractive error in pseudophakic eyes with a spectrum of underlying preoperative corneal conditions. Larger samples including different conditions should be evaluated in future studies.
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Preoperative Characteristics of Eyes Stratified by Corneal Clinical Conditionsa
|Parameter||Virgin Cornea (n = 6)||Excimer Laser (n = 12)||RK (n = 8)||ICRS (n = 5)||PK (n = 11)||DALK (n = 7)|
|Refraction sphere (D)||−2.33 ± 5.69 (+5.50 to −8.25)||−1.23 ± 2.18 (+2.75 to −4.00)||−1.13 ± 2.72 (+4.50 to −3.25)||−2.20 ± 3.17 (+2.50 to −6.00)||−2.45 ± 4.37 (+3.00 to −9.00)||−0.64 ± 4.00 (+4.00 to −7.00)|
|Refraction cylinder (D)||−0.83 ± 0.68 (0.00 to −1.50)||−1.02 ± 1.37 (0.00 to −4.00)||−3.16 ± 1.96 (−0.50 to −5.50)||−3.30 ± 0.91 (−2.50 to −4.50)||−5.00 ± 1.83 (−3.00 to −8.00)||−4.14 ± 2.79 (0.00 to −9.00)|
|ECC (cells/mm2)||2,216.00 ± 654.19 (1,359 to 2,895)||2,246.00 ± 653.26 (1,351 to 3,076)||2,104.00 ± 633.40 (1,339 to 2,904)||2,519.00 ± 159.90 (2,378 to 2,688)||1,094.00 ± 350.80 (750 to 1,880)||1,780.00 ± 504.20 (827 to 2,339)|
|IOP (mm Hg)||13.00 ± 2.75 (9 to 17)||11.67 ± 1.77 (9 to 15)||13.57 ± 1.13 (12 to 15)||13.4 ± 1.34 (12 to 15)||13.00 ± 2.66 (9 to 17)||15.57 ± 5.59 (10 to 24)|
|ICL sphere (D)||−3.33 ± 7.86 (+9.00 to −10.00)||−2.06 ± 3.05 (+2.50 to −5.50)||−3.19 ± 4.57 (+3.50 to −8.00)||−4.75 ± 4.48 (+2.25 to −9.00)||−6.55 ± 4.97 (+5.50 to −12.00)||−3.93 ± 5.79 (+4.50 to −10.50)|
|ICL cylinder (D)||–||+5.50||+5.10 ± 0.82 (+4.00 to +6.00)||+4.00 ± 1.41 (+3.00 to +5.00)||+5.64 ± 0.75 (+4.00 to +6.00)||+5.25 ± 1.06 (+4.50 to +6.00)|
|ICL size (mm)||12.23 ± 0.59 (11.50 to 13.20)||12.23 ± 0.42 (11.50 to 12.60)||12.83 ± 0.45 (12.00 to 13.20)||12.40 ± 0.45 (11.60 to 12.60)||12.44 ± 0.26 (12.00 to 12.60)||12.46 ± 0.24 (12.10 to 12.60)|
Visual Acuity Outcomes of Eyes Stratified by Corneal Clinical Conditionsa
|Parameter||Virgin Cornea (n = 6)||Excimer Laser (n = 12)||RK (n = 8)||ICRS (n = 5)||PK n = 11)||DALK (n = 7)|
|Postoperative Snellen decimal UDVA||0.73 ± 0.20 (0.40 to 0.90)||0.68 ± 0.23 (0.20 to 1.00)||0.73 ± 0.19 (0.50 to 1.00)||0.43 ± 0.26 (0.05 to 0.70)||0.37 ± 0.27 (0.05 to 0.80)||0.31 ± 0.21 (0.10 to 0.70)|
|Postoperative Snellen decimal CDVA||0.88 ± 0.16 (0.60 to 1.00)||0.78 ± 0.14 (0.60 to 1.00)||0.78 ± 0.16 (0.60 to 1.00)||0.54 ± 0.21 (0.20 to 0.70)||0.62 ± 0.25 (0.20 to 1.00)||0.54 ± 0.21 (0.20 to 0.80)|
Clinical Studies of Ciliary Sulcus Intraocular Lenses in Pseudophakic Eyes
|Kahraman & Amon9||Sulcoflex 653L||12||Myopic (5) and hyperopic (7)||6 to 17 months||1 eye with IOP increase (1 day postoperative) controlled by antiglaucoma therapy;1 decentration of the secondary lens (1 day postoperative) less than 0.5 mm and remained stable||Refractive error correction|
|Khan & Muhtaseb10||Sulcoflex||5||Plano (2) and hyperopic multifocal (4) and myopic toric (1)||10 weeks to 12 months||None||Presbyopia and refractive error correction|
|Falzon & Stewart11||Sulcoflex 653L and 653T||15||Aspheric (3) and toric (12)||5 to 12 months||1 eye with IOP increase (1 month postoperative) that remained stable without treatment; 3 eyes had increased anterior chamber flare (1 month postoperative)||Refractive error correction|
|Venter et al.12||Sulcoflex 653L||80||Hyperopic and myopic aspheric||12 months||3 eyes with of iritis (longer than 1-month postoperative) solved with topic steroids; 7 eyes with IOP solved within the first 6 weeks; 1 eye with slightly oval pupil (not noticeable and mobile/reactive to light); 1 patient reported reflection in vision||Refractive error correction|
|Huerva13||Sulcoflex 653F||1||Hyperopic multifocal||30 months||None||Refractive error correction|
|Makhotkina et al.14||Sulcoflex 653L||9||Hyperopic and myopic||3 to 22 months||1 eye required explantation due to increased positive dysphotopsia; 1 eye had small anterior chamber hemorrhage after peripheral iridotomy||Negative dysphotopsia resolution|
|Ferreira & Pinheiro15||Sulcoflex 653T||10||Toric myopic and toric hyperopic||6 to 18 months||None||Refractive error correction|
|Sinha et al.16||Sulcoflex||1||Myopic||4 weeks||None||Refractive error correction|
|Prager et al.17||Sulcoflex||48||Multifocal (25), aspheric (17) and toric (6)||12 to 84 months||None||Refractive error correction|
|Schrecker et al.18||Sulcoflex 653F||35||Multifocal||3 months||6 and 2 eyes with mild pigment dispersion with no need of treatment in the Sulcoflex and HumaOptics lenses, respectively||Presbyopia and refractive error correction|
|HumanOptics Add- On (MS 714 PB)||33||Multifocal|
|Basarir et al.19||HumanOptics Add-On||10||Hyperopic and myopic||6 to 15 months||None||Refractive error correction (2 children)|
|Thomas et al.20||HumanOptics Add- On (MS 614 TPB and MS 714 TPB)||21||Toric myopic and toric hyperopic||57 days to 6 years||5 eyes received secondary surgical alignment of axis; transient shortly: 2 eyes with increased IOP and 2 eyes with corneal edema; persisting changes: 1 eye with pigment dispersion and 2 corneal edema requiring keratoplasty||Refractive error correction|
|Ferreira et al.21||HumanOptics Torica-sPB||1||Toric||14 months||None||Refractive error|
|Schrecker et al.22||HumanOptics Diffractiva-sPB||29||Multifocal||12 months||None||Presbyopia and refractive error correction|