Angle-fixated Anterior Chamber Phakic Intraocular Lens for Myopia of -7 to -19 Diopters

Repeatability and Agreement of Horizontal Corneal Diameter Measurements Between Scanning-Slit Topography, Dual Rotating Scheimpflug Camera With Placido Disc Tomography, Placido Disc Topography, and Optical Coherence Tomography

PURPOSE

The purpose of this study was to assess the repeatability and agreement of horizontal white-to-white (WTW) measurements using 4 different imaging modalities including a slit-scanning elevation topographer, dual rotating Scheimpflug camera and Placido Disc tomographer, Placido Disc topographer, and anterior segment optical coherence (OCT) tomographer.

METHODS

In this prospective study, 33 eyes of 33 healthy subjects were scanned 3 times using each of the Orbscan IIz, Sirius, Nidek OPD III, and DRI OCT Triton devices and WTW measurements were recorded. Repeatability was assessed using the intraclass correlation coefficient (ICC), and agreement was analyzed using Bland-Altman plots.

RESULTS

Mean WTW values obtained from the Orbscan IIz, Sirius, Nidek, and DRI OCT Triton devices were 11.76 ± 0.41, 12.10 ± 0.45, 12.14 ± 0.41, and 12.40 ± 0.48 mm, respectively. Overall, there was high repeatability, with the ICC >0.86 for all devices. The Sirius showed the highest repeatability (ICC = 0.993), and the Nidek the lowest (ICC = 0.870). All pairwise comparison showed significant differences in the mean WTW measurements ( P < 0.01) except between Sirius and Nidek ( P = 0.27). Mean differences showed that the DRI OCT Triton had the highest WTW values, followed by Nidek, Sirius, and finally by Orbscan, which provided the lowest measurements. All pairwise comparisons had wide limits of agreements (between 0.60 and 0.80 mm).

CONCLUSIONS

In healthy subjects the 4 devices demonstrated high repeatability in WTW measurement. However, a poor agreement between the devices suggests that they should not be used interchangeably for WTW measurements in clinical practice.

PRESBYOPIA MANAGEMENT WITH DIFFRACTIVE PHAKIC POSTERIOR CHAMBER IOL

OBJECTIVE

To evaluate safety and refractive efficiency after posterior chamber diffractive implantable phakic contact lens (IPCL) surgery.

MATERIAL AND METHODS

A prospective non-randomized case-series study was performed on 54 myopic eyes of 27 patients who had undergone diffractive IPCL surgery. Corneal endothelial cell density (ECD), central corneal thickness (CCT), intra-ocular pressure (IOP), vault, uncorrected distance (UDVA), spherical equivalent (SE) and defocus curve, were all evaluated twelve months after surgery. The presence of cataracts was evaluated by slit-lamp during a postoperative follow-up.

RESULTS

Mean age was 47 ± 2.62 years-old. Mean SE decreased, from -5.95 ± 2.56 D in a pre-operative stage, to -0.25 ± 0.25 D twelve months after surgery. Achieved UDVA was 20/20 in 24.1% of all cases, 20/25 in 74.1% of them, and 20/32 in all remaining cases. No eyes suffered lost lines of vision. The binocular defocus curve was 0.06 ± 0.05 logMAR for a -3.0 D of defocus; 0.11 ± 0.04 logMAR for a -1.5 D of defocus, and 0.08 ± 0.03 logMAR for a 0 D of defocus. Twelve months after surgery, mean ECD had decreased by 1.43 %, whereas mean CCT had increased by 0.06 %, without any significant statistical difference (p = 0.28 and p = 0.93 respectively). No difference (p: 0.86) in the vault was observed at 6 months vs.12 months, as well as between IOP measurements (p = 0.22). There were no non-intra or postoperative complications, and, specifically, no cataracts developed either.

CONCLUSIONS

Diffractive IPCL was implanted safely. Corneal endothelial CD, CCT, vault, and IOP remained stable twelve months after surgery. Visual acuity for distance, intermediate and near sight were achieved without spectacles.

Bioptics by Angle-Supported Phakic Lenses and Photorefractive Keratectomy

PURPOSE

To assess efficacy and safety of the combination of angle-supported phakic intraocular lenses (IOLs) and photorefractive keratectomy (PRK) for the correction of myopia and astigmatism.

METHODS

Prospective, non-randomized single-surgeon study on 48 patients (76 eyes) undergoing angle-supported phakic IOL implantation with surgical peripheral iridectomy, followed 2 to 3 months later by PRK to correct residual refractive error. Twenty-three patients (33 eyes) achieved good uncorrected visual acuity with IOL implantation alone and did not undergo PRK. Thus, the study was completed by 25 patients (43 eyes) with preoperative mean defocus equivalent (DEQ) of 15.73 D (SD 4.67 D) and mean astigmatism of -2.87 D (SD 1.39 D).

RESULTS

Eight months after PRK, mean spherical equivalent was -0.08. Mean DEQ was 0.47 D (SD 0.37); 42/43 eyes (98%) were within +/-1 D of DEQ, and 33/43 eyes (77%) within +/-0.5 D. Mean uncorrected visual acuity was 0.7 (SD 1.9). Safety index was 1.25; efficacy index 1.11. Best-corrected visual acuity improvement (0.16) was statistically significant (95% CI: 1.1 to 2). Halos were moderate in 6/25 patients (24%); severe in 1/25 patients (4%). Endothelial cell density decreased by -6.6%. Pain after PRK was severe in 3/25 patients (12%) and moderate in 13/25 patients (52%). Complications were recurrent iridocyclitis in one eye, transient ocular hypertension in two eyes, and incomplete iridectomy in one eye.

CONCLUSIONS

Angle-supported phakic IOLs followed by adjustment by PRK offer good efficacy, predictability, and safety to manage large refractive myopic errors.

Phake Intraokularlinsen

Die Implantation von phaken Intraokularlinsen stellt eine etablierte Therapieform zur Korrektur von höhergradigen Ametropien bei Myopie und Hyperopie sowie kombinierten Refraktionszuständen mit Astigmatismen dar. Bei der Anwendung sind gewisse anatomische und refraktive Voraussetzungen zu beachten. Der Artikel beschreibt die aktuell gängigen Verfahren und Intraokularlinsensysteme unter besonderer Berücksichtigung der Möglichkeiten und Grenzen.

An angle-supported foldable phakic intraocular lens for correction of myopia: A five-year follow-up

OBJECTIVE

To evaluate the efficacy and safety of an angle-supported foldable phakic intraocular lens (pIOL) for the correction of moderate to high myopia after 5 years follow-up.

METHODS

Prospective and retrospective, observational, longitudinal, non-randomised consecutive series of cases conducted on a total of 100 eyes of 67 patients with moderate to high myopia implanted with an Acrysof Cachet pIOL (Alcon Laboratories Inc.) with the aim of minimising the refractive error. The ages ranged between 18 to 60years. Uncorrected distance visual acuity (UDVA), manifest refraction, corrected distance visual acuity (CDVA), endothelial cells density, pIOL position, intraocular pressure, and complications were recorded preoperatively and during the 5 year follow-up.

RESULTS

Five years after implantation, the mean manifest spherical equivalent refraction reduced significantly from -11.62±3.35 dioptres (D) to -0.33±0.85D. UDVA was 20/20 or better in 5 of 25 cases (20%), and 20/40 or better in 22 cases (88%). CDVA was 20/20 or better in 17 cases (68%), and 20/32 or better in 23 cases (92%) of eyes. The residual refractive error was within ±0.50D of emmetropia in 12 cases (48%), and within ±1.00D in 19 cases (76%). Mean endothelial cell loss at 5 years was 11.8% central, and 13.7% peripheral. Mean endothelium-pIOL distance was 2.11±0.18mm, and mean pIOL-crystalline distance was 0.88±0.20mm.

CONCLUSIONS

This angle supported pIOL provided a favourable refractive correction and predictability, as well as acceptable safety in patients with moderate to high myopia. Although endothelial cell density decreased over 5years, the results are within the range reported in previous studies with other pIOLs.

Asymptomatic haptic migration of phakic anterior chamber intraocular lens through the peripheral iridectomy

OBJECTIVE

Case series of haptic migration in patients with angle-supported phakic anterior chamber intraocular lens (PAC-IOL: Phakic6H) through the superior peripheral iridectomy (PI).

METHODS

Charts of 23 patients (35 eyes) with at least 6 months' postoperative follow-up were retrospectively reviewed. Evaluation included preoperative and postoperative cycloplegic and manifest refractions, uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), slit-lamp examination, fundoscopy, corneal topography, and biometry.

RESULTS

Mean UCVA was 1.67 ± 0.30 (1.17-2.00) for all 35 eyes preoperatively and 0.35 ± 0.25 (0.00-1.00) postoperatively (p < 0.001; 95% CI 1.21-1.44). BCVA had a mean of 0.31 ± 0.26 for all 35 eyes preoperatively, and a mean of 0.22 ± 0.25 postoperatively (p < 0.001; 95% CI 0.04-0.14). Haptic migration into the superior PI was noted in 8 eyes (23%). The first migration was noted 2 years postoperatively and the last 8 years after implantation (mean, 5.6 ± 2 years). There was no statistically significant difference in the BCVA and UCVA before and after haptic migration. Follow-up ranged from 8 months to 8.5 years.

CONCLUSIONS

Angle-supported PAC-IOL implantation resulted in significant improvement in both UCVA and BCVA. However, there is a 23% incidence of haptic migration in our series with no sequelae on BCVA or harmful effect on the intraocular structures. This IOL movement may be explained by changes in aqueous dynamics at the level of the PI leading to migration of the haptic into the area of least resistance.

Iris atrophy and erosion caused by an anterior-chamber angle-supported phakic intraocular lens

We report a case in which an angle-supported phakic IOL was implanted to correct high myopia. Subsequently, the patient experienced photophobia, glare, halo, and loss of visual acuity and became concerned about the cosmetically deforming aspect of her eye. Findings included endothelial cell loss, cataract, pupil ovalization, and severe iris atrophy. The pIOL was removed and cataract surgery was performed, followed by implantation of a bag-in-the-lens IOL, but successful surgical repair of the iris was not possible because of severe iris atrophy.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

[Scheimpflug photography for the examination of phakic intraocular lenses]

BACKGROUND

High myopia phakic intraocular lenses (IOL) have become an established means of surgical correction for high ametropia. Scheimpflug photography is one of the methods which are frequently applied for postoperative examination of the implants.

MATERIAL AND METHODS

Results from published studies employing Scheimpflug photography for examination of anterior chamber angle-fixated, iris-fixated and sulcus-fixated phakic IOLs were evaluated.

RESULTS

In several published studies Scheimpflug photography was used to examine the position of the implant and opacification of the crystalline lens. The results provided valuable evidence for the improvement of phakic IOL design.

CONCLUSION

Scheimpflug photography offers an easy to use, rapid non-contact examination of phakic IOLs.

Anterior segment optical coherence tomography of long-term phakic angle-supported intraocular lenses

PURPOSE

To evaluate the long-term age-related anterior chamber changes by anterior segment optical coherence tomography (OCT) and the impact of such changes on the stability and behavior of angle-supported phakic intraocular lenses (IOLs).

DESIGN

A retrospective consecutive observational cohort study.

METHODS

A total of 23 eyes with high myopia implanted with an angle-supported phakic IOL between 1990 and 1996 at Vissum Corporación Oftalmológica de Alicante were included in the study. Patients were evaluated using OCT. Anterior chamber depth, anterior chamber width, crystalline lens rise, and the distance between phakic IOL and endothelium were measured.

RESULTS

Fifteen years after implantation, anterior chamber depth was 2.9 ± 0.3 mm, crystalline lens rise 748.18 ± 393.13 μm, and phakic IOL-endothelium distance 2.1 ± 0.30 mm. The predictive model showed that 30 years after implantation, endothelial cell count was less than 600 cells/mm(2) in patients with a preoperative spherical equivalent of -25 diopters (D). Twenty years after implantation, the safety zone of 1.5 mm between endothelium and the lens will not be respected in patients with a preoperative spherical equivalent of -20 D.

CONCLUSIONS

The findings of this study could have an important influence on the decision about the indication to implant angle-supported phakic IOLs in young patients with a long postoperative life expectancy, as age-related changes in the anatomy of the anterior segment may create a long-term hazard for the implanted eye.

Intraocular optical quality of phakic intraocular lenses: comparison of angle-supported, iris-fixated, and posterior chamber lenses

PURPOSE

To evaluate internal aberrometric profiles following phakic intraocular lens (PIOL) implantation.

DESIGN

Retrospective and consecutive case series.

METHODS

One hundred and five eyes of 65 patients were included. The optical aberrations were measured with the Topcon KR-1W aberrometer. Comparisons of internal aberrations for different models were made. Comparisons at 4 and 6 mm were made also within the same model for all the lenses. Comparisons regarding the implantation site were also performed: angle-supported (AS) anterior chamber (AC) (n = 47), iris-fixated (IF) (n = 27), and posterior chamber (PC) (n = 31).

RESULTS

Root mean square (RMS) of internal optical higher-order aberrations (HOAs) changed significantly to higher values from 4-6 mm aperture diameter in each PIOL, as should be expected. However, this significant change was not detected in spherical aberration for Kelman Duet (P = .753) and in trefoil for Acrysoft (P = .059). Kelman lens showed significantly lower values of spherical aberration compared to Acrysoft at 4 mm (P = .022) and at 6 mm (P = .042). Acrysoft showed the lowest values at central zone for trefoil (P = .043) and tetrafoil (P = .002) in AC group. In the IF group, Artisan and Artiflex showed similar results for all internal aberrations. In the comparison between Visian Implantable Collamer Lens (ICL; STAAR Surgical Co, Monrovia, California, USA) and phakic refractive lens (PRL), both for posterior chamber, significantly lower values of coma were observed for ICL (P = .033). IF lenses showed clinical evidence, but not significant, of better centering capability than AS lenses (P = .096).

CONCLUSIONS

The study of intraocular aberrations is an adequate method to identify the clinical optical behavior and could help the surgeon to identify the most frequent problems related with each model.

Posterior chamber phakic intraocular lens to correct myopia: long-term follow-up

PURPOSE

To evaluate the long-term safety and efficacy of a refractive phakic intraocular lens (pIOL) (PRL) to correct moderate to high myopia.

SETTING

Department of Ophthalmology, University Medicine Charité Berlin, Berlin, Germany.

DESIGN

Retrospective cohort study.

METHODS

Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure, endothelial cell loss, and adverse events were evaluated.

RESULTS

The study enrolled 53 eyes (mean spherical equivalent [SE] -12.17 diopters [D] ± 4.12 [SD]) of 29 patients. The mean age was 34.6 ± 9.2 years and the mean follow-up, 86 ± 21.2 months. The mean UDVA improved from 1.37 ± 0.28 logMAR preoperatively to 0.14 ± 0.19 logMAR at the last postoperative visit (P<.05). The mean CDVA improved from 0.10 ± 0.18 logMAR to -0.01 ± 0.09 logMAR (P<.05). The overall mean efficacy index and mean safety index were 0.9 and 1.21, respectively, at the last follow-up visit. The mean endothelial cell loss at the last follow-up was 6.4%. The complications were slight posterior chamber (PC) pIOL decentration (5 eyes, 9.4%), severe PC pIOL decentration resulting in pIOL removal (1 eye, 1.8%), glaucoma (4 eyes, 7.5%), clinically significant cortical lens opacification resulting in cataract surgery (4 eyes, 7.5%), clinically asymptomatic anterior subcapsular cataract formation (6 eyes, 11.3%), and retinal detachment (2 eyes, 3.8%).

CONCLUSIONS

Posterior chamber phakic pIOL implantation to correct moderate to high myopia provided predictable and stable refractive results but with a high rate of serious complications over the long term.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Refractive lens exchange versus phakic intraocular lenses

PURPOSE OF REVIEW

To review the evidential basis of current practice in refractive lens exchange (RLE) vs. phakic intraocular lens (pIOL).

RECENT FINDINGS

Visual outcomes after pIOLs are better than RLE. With RLE, there still remain risks of retinal detachment, cystoid macular oedema, glare, halos and posterior capsule opacification. With pIOLs, risks include pigment dispersion, cataract formation, glaucoma and inflammation. The decision to choose between either is broadly based on age and type of refractive error, and the choice follows thorough evaluation and counselling taking into consideration patient's needs and expectations.

SUMMARY

With advancing technology, newer IOL models for RLE and phakic correction are becoming available. pIOLs provide better visual outcomes for distance correction and currently do not provide near-vision correction possible with RLE.

Intraocular stability of an angle-supported phakic intraocular lens with changes in pupil diameter

PURPOSE

To use anterior segment optical coherence tomography (AS-OCT) to evaluate the stability of a recently released angle-supported phakic intraocular lens (pIOL) in the anterior segment with changes in pupil diameter.

SETTING

Keratoconus Unit, Vissum Corporation, Alicante, Spain.

METHODS

In this observational cross-sectional study of consecutive eyes with moderate to high myopia, an AcrySof Cachet pIOL was implanted with the aim of minimizing the refractive error. An analysis of the position and stability of the pIOL before and after pharmacologic pupil dilation was performed 3 months postoperatively using the Visante AS-OCT system. A measurement protocol that included several anatomic parameters was developed and applied; the parameter values before and after dilation were compared.

RESULTS

Twenty eyes of 20 patients ranging in age from 24 to 48 years old were evaluated. The anterior chamber depth increased significantly with pupil dilation (mean change 0.06 mm +/- 0.08 [SD]) (P<.01). A significant change was also observed in the distance between the center of the cornea at the endothelial plane and the anterior surface of the pIOL (mean change 0.03 +/- 0.05 mm) (P = .01). The distances between the peripheral edges of the pIOL and the corneal endothelium and the distance between the crystalline lens and the pIOL did not change significantly (P>or=.14).

CONCLUSION

The angle-supported pIOL showed excellent intraocular behavior after pupil dilation, with no shortening of the distance between the pIOL and corneal endothelium at the center or peripheral edges of the pIOL.

Refractive stability of LASIK with the Visx 20/20 excimer laser vs ZB5m phakic iol implantation in patients with high myopia (>-10.00 d): a 10-year retrospective study

PURPOSE

To compare the long-term outcomes of LASIK and ZB5M phakic intraocular lens implantation (PIOL) (Domilens) for high myopia (>-10.00 diopters [D]).

METHODS

This long-term (10 years) follow-up retrospective interventional case series study included 126 eyes that underwent LASIK and 52 eyes that underwent ZB5M angle-supported PIOL implantation. Both groups of eyes were similar in terms of preoperative spherical equivalent refraction (SE), corrected distance visual acuity (CDVA), and age.

RESULTS

Mean preoperative SE was -14.33 D in the LASIK group and -14.84 D in the PIOL group. At 10-year follow-up, mean postoperative SE was -1.47±2.00 D in the LASIK group and -1.01±1.36 D in the PIOL group (P=.21). In the LASIK group, 67% of eyes were within ±1.00 D of emmetropia at 2 years after surgery, compared to 42% at 10 years. In the PIOL group, 68% of eyes were within ±1.00 D of emmetropia 2 years after implantation compared to 53% at 10 years. In the LASIK group, 43.5% of eyes achieved UDVA of 20/40 or better 10 years after surgery compared to 67.9% in the PIOL group (P=.02).

CONCLUSIONS

The ZB5M angle-supported PIOL was shown to have better predictability and stability compared to LASIK over 10 years. However, reductions in endothelial cell count over time were observed in eyes with PIOLs.

Spherical implantable collamer lenses for myopia and hyperopia: 126 eyes with 1-year follow up

BACKGROUND

To report on 1-year follow up of a series of 126 eyes implanted with a spherical implantable collamer lens (ICL).

METHODS

Retrospective case note review of 126 eyes (68 patients) undergoing ICL placement by a single surgeon (TG) to correct preoperative mean spherical equivalents between +8.88 and -20.50 D. Main outcome measures included uncorrected visual acuity (UCVA), refraction, best spectacle-corrected VA, unaided binocular vision, adverse events, operative/postoperative complications and patient symptoms.

RESULTS

Complete data were available at 1 year on 121 of the 126 eyes (65 out of 68 patients). At 12 months 86% (104/121) had postoperative UCVA better than or equal to preoperative best spectacle-corrected VA, and 98% (118/121) had UCVA within one line of preoperative best spectacle-corrected VA. Ninety-six per cent (116/121) had postoperative UCVA of 6/9 or better, and 100% had postoperative best-corrected visual acuity of 6/12 or better. Ninety-eight per cent (64/65) patients had unaided binocular vision at 1 year of 6/7.5 or better. Average myopia treated was -8.83 D (116 patients), and average hyperopia +7.14 D (10 patients). Two ICLs were replaced because of high vaulting; one eye had increased intraocular pressure that resolved with smaller ICL placement. Four patients had visually insignificant pigment deposits on the ICL at 3/12, but no pigmentary glaucoma. Five patients noticed haloes around lights at night, none preventing driving.

CONCLUSIONS

One-year results from this study, the largest reported clinical investigation of the use of ICLs in New Zealand, support the safety, efficacy and predictability of ICL to treat both hyperopic and myopic spherical refractive errors.

Fifteen-year follow-up after anterior chamber phakic intraocular lens implantation in one and LASIK in the fellow eye

PURPOSE

To report a patient fifteen years after anterior chamber phakic intraocular lens (AC-PIOL) implantation in one and laser in situ keratomileusis (LASIK) in the fellow eye.

METHODS

Case report.

RESULTS

A 56-year-old male underwent AC-PIOL implantation in one eye and LASIK in the fellow eye fifteen years ago. Preoperative uncorrected visual acuity (UCVA) was finger count in both eyes. Preoperative best spectacle-corrected visual acuity (BSCVA) was 20/25 (-16.75 -0.50 x 40) in the LASIK eye and 20/32 (-24.50 -0.50 x 90) in the AC-PIOL eye. Fifteen years postoperatively, UCVA was finger count in the LASIK eye and 20/200 in the AC-PIOL eye, while BSCVA was 20/32 and 20/25, respectively. Endothelial cell density (ECD) was 2020+/-47 in the LASIK eye and 945+/-22 in the AC-PIOL eye.

CONCLUSION

Both procedures had similar visual outcomes. Furthermore, lower ECD was found in the AC-PIOL eye in comparison to the LASIK eye.

Comparison of internal anterior chamber diameter imaging modalities: 35-MHz ultrasound biomicroscopy, Visante optical coherence tomography, and Pentacam

PURPOSE

To compare the internal diameter of the anterior chamber among three different imaging modalities: 35-MHz ultrasound biomicroscopy (UBM), Visante optical coherence tomography (OCT), and Pentacam, and to compare the internal diameters with white-to-white (WTW) distance measured by Orbscan.

METHODS

The internal horizontal anterior chamber diameter was measured in 20 normal eyes using 35-MHz UBM (Optikon), Visante OCT (Carl Zeiss Meditec), and Pentacam (Oculus Inc). The mean horizontal anterior chamber diameters were compared, and the correlations between each pair of two different methods were evaluated. Horizontal WTW distance was measured by Orbscan IIz (Bausch & Lomb-Orbtek Inc) and then correlated with the measurements of internal anterior chamber diameter.

RESULTS

The mean horizontal anterior chamber diameter was 10.99+/-0.47 mm with UBM, 11.70+/-0.47 mm with OCT, and 11.86+/-0.45 mm with Pentacam. Ultrasound biomicroscopy measurements were significantly different than those of OCT and Pentacam (P<.001 for both). However, no significant difference was found between OCT and Pentacam (P=.19). Regarding the correlations between each pair of two different methods, UBM and OCT showed significant correlation (r=0.848, P<.001), but there was no significant correlation between OCT and Pentacam (r=0.403, P=.078), even though the mean values were similar. In the Bland-Altman plots, the range of agreement was 0.51 mm between OCT and UBM, and 0.99 mm between Pentacam and OCT.

CONCLUSIONS

Although the internal anterior chamber diameters measured by 35-MHz UBM were significantly smaller than those measured by Visante OCT and Pentacam, the measurements of UBM and Visante OCT showed significant correlation and good agreement with each other. Pentacam showed poor correlation with other measurements.

Corneal diameter measurements by corneal topography and angle-to-angle measurements by optical coherence tomography: evaluation of equivalence

PURPOSE

To determine the equivalence of corneal white-to-white (WTW) diameter and anterior segment angle-to-angle (ATA) measurements.

SETTING

Vissum Instituto Oftalmologico de Alicante, Alicante, Spain.

METHODS

Thirty eyes of 19 patients ranging in age from 20 to 51 years old with no previous ocular surgeries were included in this study. In all cases, the horizontal WTW diameter was measured with a tool provided by the CSO corneal topography system (Costruzione Strumenti Oftalmici) and the horizontal ATA was measured using an optical coherence tomography (OCT) system (Visante, Carl Zeiss Meditec AG). All measurements were repeated 3 times to evaluate intrasession repeatability. The correlation between WTW and ATA measurements was studied, and the interchangeability of the 2 parameters was assessed using the Bland and Altman method.

RESULTS

The mean corneal WTW diameter was 12.25 mm +/- 0.49 (SD) (range 11.34 to 13.16 mm), and the mean ATA distance was 11.76 +/- 0.52 mm (range 10.03 to 12.92 mm). The difference between the 2 parameters was statistically significant (P<.01). A weak, although statistically significant, positive correlation (r = 0.39; P = .03) and a nonpredictive linear model were found. The Bland and Altman analysis showed large limits of agreement between WTW and ATA measurements that are clinically relevant (limits of agreement, -1.59 mm and 0.61 mm). The intrasession repeatability scores for the WTW and ATA measurements were good.

CONCLUSIONS

The WTW and ATA distance measurements were not equivalent and thus are not interchangeable. There was no linear model for an accurate prediction of the ATA from the WTW.

Severe endothelial cell loss following uneventful angle-supported phakic intraocular lens implantation for high myopia

Endothelial decompensation is a serious complication of phakic intraocular lens (pIOL) implantation and is a major concern during the postoperative period. We report 3 eyes in which the same foldable angle-supported pIOL was implanted to correct high myopia. Rapid and severe postoperative endothelial cell loss occurred in all 3 eyes. An over-sized pIOL that induced excessive vaulting into the anterior chamber was the main risk factor. In 2 eyes, the pIOL was explanted uneventfully; 1 eye required Descemet's stripping automated endothelial keratoplasty because of total endothelial decompensation. These cases illustrate the importance of accurate sizing of foldable angle-supported anterior chamber pIOLs to avoid excessive vaulting. They also highlight the importance of regular follow-up and preventive pIOL explantation as soon as significant endothelial cell loss is detected.

Two-year follow-up of the Artisan/Verisyse iris-supported phakic intraocular lens for the correction of high myopia

PURPOSE

To evaluate the implantation of Artisan/Verisyse phakic intraocular lenses (pIOLs) (Advanced Medical Optics) as an effective and safe method for the correction of high myopia.

SETTING

Department of Ophthalmology, John A. Moran Eye Center, University of Utah Medical Center, Salt Lake City, Utah, USA.

METHODS

This retrospective outcomes trial examined the implantation of Artisan/Verisyse pIOLs in 85 highly myopic eyes (mean spherical equivalent -12.2 diopters). Patients were followed for 2 years and examined postoperatively at 1,6,12, and 24 months. Data collected included best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), corneal endothelial cell density, and adverse events.

RESULTS

Six months postoperatively, 5 (7%) eyes lost 1 line of the BSCVA; no eye lost 2 or more lines. The UCVA was better than 20/40 in 83% of eyes and better than 20/25 in 32%. Endothelial cell density decreased by 3.3% and 6.5% over the 1-year and 2-year intervals, respectively. Glare and halos, the most common complications of surgery, were reported by 6% of patients at 1 month and by 3% at 2 years.

CONCLUSION

Implantation of the Verisyse/Artisan pIOL yielded accurate refractive results with acceptable safety in highly myopic eyes.

Outcomes of ZB5M Angle-supported Anterior Chamber Phakic Intraocular Lenses at 12 Years

PURPOSE

To evaluate the visual and refractive stability and the potential long-term risks associated with ZB5M phakic intraocular lens (PIOL) implantation.

METHODS

A retrospective, non-randomized, cumulative clinical study was performed over 12 years in a consecutive group of 225 eyes implanted with the ZB5M PIOL. The main analyzed variables were visual and refractive outcomes (best spectacle-corrected visual acuity [BSCVA], uncorrected visual acuity [UCVA], and spherical equivalent), endothelial cell density, and postoperative complications.

RESULTS

Mean preoperative spherical equivalent refraction was -17.23 +/- 7.69 diopters (D) and 12 years postoperatively it was -1.80 +/- 0.80 D. Mean BSCVA at 1- and 12-year follow-up was 0.38 +/- 0.19 and 0.57 +/- 0.18, respectively (Wilcoxon test, P < .001). At 12 years postoperatively, 3.5% of eyes lost > or = 2 lines of BSCVA. An initial 10.6% reduction in endothelial cell density was noted in the first year, followed by a mean annual rate of decrease of 1.78%. The cumulative incidence of pupil ovalization was 34.7% (78 eyes), and there was no statistical correlation with endothelial cell impairment. Bilateral hypertensive uveitis was diagnosed in 3 (1.33%) eyes.

CONCLUSIONS

The ZB5M PIOL offers good refractive outcomes and stability in the long-term; however, endothelial cell loss increases over 12 years, requiring annual endothelial cell counts.

Traumatic pupillary capture of the haptic of an angle-supported phakic intraocular lens

A 27-year-old woman had implantation of an angle-supported phakic intraocular lens (pIOL) for myopia in the left eye in 2003. Moderate iris atrophy and pupil ovalization were noted in 2005. In 2006, the eye was hit by a plastic bullet shot from a toy gun. The pupil became distorted as the inferior haptic engaged the pupil edge. Visual acuity was not affected. Surgical repositioning was uneventful, yielding a round pupil with no damage to the iris sphincter or the lens. The endothelium was not affected by the trauma or surgery. Previous iris atrophy may have facilitated pupillary capture because of reduced iris elasticity and pupil ovalization by the haptic. Blunt trauma can dislocate angle-supported pIOLs. Implantation of these IOLs should be discouraged in patients who perform activities that put them at risk for eye trauma.

Clinical Results With the Medennium Phakic Refractive Lens for the Correction of High Myopia

PURPOSE

To evaluate the predictability, safety, stability, complications, and biocompatibility of the phakic refractive lens (PRL) as a posterior chamber intraocular lens to correct high myopia.

METHODS

Fifty eyes of 31 patients who underwent posterior chamber PRL implantation were evaluated prospectively. Mean preoperative myopia was -12.54 +/- 4.22 diopters (D) (range: -4.50 to -23.50 D) and mean astigmatic refractive power was -1.38 +/- 1.24 D (range: -1.00 to -4.50 D). Surgical implantation was performed through a 3.0- to 4.0-mm clear cornea sutureless incision using parabulbar (sub-Tenon's) anesthesia. Intra- and postoperative complications were recorded.

RESULTS

Three months after surgery, the mean spherical equivalent refraction was -0.21 +/- 0.42 D (range: +1.00 to -1.75 D). At 6 and 12 months, mean spherical equivalent refraction was -0.23 +/- 0.38 D (range: 0 to -1.25 D). At the last examination, uncorrected visual acuity was > or = 20/40 in 41 (82%) eyes and > or = 20/20 in 22 (44%) eyes. Best spectacle-corrected visual acuity (BSCVA) was > or = 20/40 in 42 (84%) eyes and > or = 20/20 in 27 (54%) eyes. Comparison of pre- and postoperative BSCVA at 12 months showed that 12 (36.4%) of 33 eyes gained > or =1 lines of BSCVA and 7 (21.2%) of 33 eyes gained > or =2 lines. One (2%) eye developed anterior subcapsular cataract requiring lens exchange, and 1 (2%) eye developed acute angle closure glaucoma requiring YAG-iridotomy. One (2%) eye developed macular hemorrhage.

CONCLUSIONS

At 6 months and 1 and 2 years, PRL implantation yielded encouraging visual and refractive results with excellent biocompatibility. The efficacy, stability, and short-term safety of this lens was established. Serious complications, such as cataract and acute angle closure glaucoma, may occur, and long-term safety needs to be evaluated.

[GBR foldable anterior phakic intraocular lens with angular supports: a 3-year experience]

PURPOSE

The purpose of this study was to evaluate the efficiency, predictability, and safety of the GBR foldable anterior chamber implant with angular supports to correct high myopia after 3 years of follow-up.

MATERIAL

and methods: A GBR anterior chamber lens with angular supports was implanted in 44 eyes between November 2001 and February 2004. These eyes were highly myopic (preoperative mean of -10.65 +/- 2.62 diopters (D) (range, -6.25 to -16.50 D). Visual acuity, refraction, biomicroscopy, and quality of vision were estimated with a follow-up of 3 years. The potential complications required endothelial density, mobility of the pupil, intraocular pressure, and gonioscopy measurements.

RESULTS

No severe intra- or postoperative complications required an ablation of the lens. Increased intraocular pressure in three cases and decentration in one were the most serious side effects reported. Eighteen eyes (40.9%) presented pupil ovalization; 68.2% of the eyes reached the attempted correction +/-0.50 D. Implants seemed stable in their position and refractive results. Functional signs included night glare for eight patients (18.2%) and glare in the sun for 11 (25%). There was no significant decrease in cellular endothelial density mean during follow-up.

CONCLUSION

The GBR implant (Ioltech) is the pioneer of foldable anterior chamber implants, a concept in full expansion. Long-term satisfaction of the operated patients is encouraging. However, the medium-term anatomical modifications noted require monitoring and a search for the responsible mechanism.

Cataractous Changes due to Posterior Chamber Flattening with a Posterior Chamber Phakic Intraocular Lens Secondary to the Administration of Pilocarpine

OBJECTIVE

To present the first reported case of cataract formation as a consequence of instillation of pilocarpine in an eye with a posterior chamber phakic intraocular lens (IOL).

DESIGN

Interventional case report.

INTERVENTION

A 46-year-old man received a hyperopic implantable collamer lens (ICL) bilaterally.

MAIN OUTCOME MEASURES

Determination of best-corrected visual acuity (BCVA); contrast sensitivity testing with and without glare; and intraocular pressure (IOP), specular endothelial cell, and slit-lamp examinations were performed serially. In addition, the distance between the ICL and crystalline lens was measured with optical coherence tomography.

RESULTS

Both eyes underwent uneventful ICL implantation for the correction of a manifest spherical equivalent of +7 diopters (D) in the right eye and +7.1 D in the left eye. The left eye was followed for 2 years without developing complications. The right eye, however, showed on the first postoperative day a fleckenlike opacification on the anterior pole of the crystalline lens after instillation on the operative day of 2% pilocarpine in an attempt to accelerate recovery from unwanted pupil dilation causing patient complaints of glare disability after surgery. Optical coherence tomography demonstrated complete contact of the ICL with the natural lens 24 hours postoperatively. Serial IOP measurements were always within the normal limits. The instillation of 1% cyclopentolate resulted in an increase in the ICL vault that measured 132 mum 24 hours later. Three days after the completion of a 3-day course of topical 1% cyclopentolate, the opacification was less dense and demarcated, and a 124-mum vault was measured. Three months postoperatively, the cataract was associated with a 3-line loss of BCVA and considerable degradation of the contrast sensitivity, especially at higher spatial frequencies and with a glare source, and corneal endothelial cell changes were within normal limits. One year after ICL implantation, the right eye had to undergo phacoemulsification and IOL implantation, which were uneventful.

CONCLUSIONS

Posterior chamber flattening with resulting crystalline lens opacification can occur immediately after the instillation of pilocarpine in an eye with a hyperopic ICL. Therefore, caution should be taken with the administration of cholinergic agonists such as pilocarpine in patients with phakic IOLs, at least if they are hyperopic ICLs.

Surgical Correction of Hyperopia

Surgical attempts to correct hyperopia have yielded varying results over the last 130 years. These techniques include the reshaping of the cornea through incisions, burns, or lamellar cuts with removal of peripheral tissue; the addition of central inlays; laser ablations; and the replacement of the crystalline lens. By examining the success of each surgical technique, the refractive surgeon may be able to make an informed decision on its indications and limitations, based on the specific patient's characteristics. Reporting the outcomes and complications of hyperopic surgery will help refine our approach to the management of an increasingly hyperopic and presbyopic population.

Correction of high myopia with different phakic anterior chamber intraocular lenses: ICARE angle-supported lens and Verisyse iris-claw lens

PURPOSE

To evaluate the efficacy, predictability and safety of implanting two models of anterior chamber IOLs for high myopia. Comparison of the refractive results between two groups of patients implanted with different IOLs.

MATERIALS AND METHODS

Forty eyes were implanted with phakic IOLs. The ICARE myopia lens was implanted in 20 eyes of 12 patients with preoperative myopia that ranged from -21.875 to -10.0. The mean patients' age was 30 years. The Verisyse IOL was implanted in 20 eyes of 12 patients with spherical equivalent of the refractive error from -21.625 to -10.375D, and the mean patients' age was 32.25 years. The dioptric power of the intraocular lens was calculated by considering refraction, keratometry, and anterior chamber depth. The follow-up period was 12 months.

RESULTS

Twelve months after surgery, the mean refractive error (SE) was -0.19D (100% of eyes were within +/-1.0D of the target refraction) in the ICARE group, and -0.86D (95% of eyes were within +/-1.0D of the target refraction) in the Verisyse group. The postoperative refraction remained stable during the entire follow-up period. The mean uncorrected visual acuity was 0.7 in the ICARE group, and 0.69 in the Verisyse group 1 year postoperatively. There was no loss in visual acuity 1 year after surgery in the ICARE implanted eyes, one patient in the Verisyse group lost 1 line of BCVA as compared to the preoperative state. Mean endothelial cell density loss was 6.12% and 6.79% in the ICARE and Verisyse groups, respectively. There were no statistically significant differences regarding the analyzed outcome parameters between the two study groups.

CONCLUSION

The implantation of both anterior chamber phakic intraocular lenses to correct high myopia resulted in a stable and predictable refractive outcome. Efficacy and safety of surgery for both implanted lens models are very high.

Visual improvement in high myopic amblyopic adult eyes following phakic anterior chamber intraocular lens implantation

PURPOSE

To evaluate the efficacy and safety of angle-supported phakic anterior chamber intraocular lenses in amblyopic adult eyes with very high myopia.

METHODS

We evaluated 12 eyes in nine patients with very high myopic amblyopia who received angle-supported phakic intraocular lenses (Phakic 6H) and followed them for more than six months. Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and complications were evaluated. A satisfaction score was rated by patients using a 5-point (1-5) numeric scale.

RESULTS

The mean age of patients was 37.3 +/- 9.4 years, ranging from 29 to 59 years old. The preoperative mean refraction (spherical equivalent, SE) was -20.10 +/- 5.41 diopters (D). The postoperative mean refraction (SE) was -1.75 +/- 0.76 D at six months. The postoperative BCVA improved an average 3.92 +/- 1.24 lines over preoperative values, and mean endothelial cell loss was 8.9% at six months. Development of cataracts, glaucoma, and pupil abnormalities were not demonstrated in any case during the study. The patients were all very satisfied, as the average satisfaction score was 4.3.

CONCLUSIONS

This study indicates that angle-supported phakic anterior chamber intraocular lens implantation may be an effective surgical alternative for the correction of amblyopic adult eyes with very high myopia. However, long-term evaluation is necessary to assess possible complications and long-term safety.

Iridocyclitis associated with angle-supported phakic intraocular lenses

PURPOSE

To evaluate incidence, features, risk factors, and prognosis of iridocyclitis after angle-supported phakic intraocular lens (IOL) implantation.

SETTING

Private practice, Siena, Italy.

METHODS

This retrospective analysis comprised 356 consecutive eyes of 212 patients. In myopic eyes, the ZSAL-4 IOL (205 eyes of 125 patients) or the ZSAL-4 Plus IOL (106 eyes of 63 patients) was used. In hyperopic eyes (45 eyes of 24 patients), the Type 54 IOL was implanted. Haptic posterior angulation was 19 degrees (ZSAL-4), 23 degrees (ZSAL-4 Plus), and 14 degrees (Type 54).

RESULTS

Clinically significant iridocyclitis occurred in 11 eyes (3.1%) of 11 patients. Mean patient age was 37.3 years +/- 9.4 (SD). Sixty-four percent were male (odds ratio [OR], 3.0; 95% confidence interval [CI], 0.8 to 7.4, not statistically significant). Iridocyclitis was observed in 4.4% of hyperopic eyes (OR, 1.6; 95% CI, 0.3 to 7.4; not statistically significant) and in 2.9% of myopic eyes. In myopic eyes, it followed the implantation of ZSAL-4 IOL in 3.9% of eyes (OR, 4.1; 95% CI, 0.5 to 33.6; not statistically significant), and of ZSAL-4 Plus IOL in 1%. Mean time from surgery was 8.5 +/- 10.6 months). Presentation included aqueous flare (100%), posterior synechiae (82%), blurred vision (82%), redness (36%), pain (27%), IOL precipitates (18%), and angular synechiae (9%). Only 1 patient had recurrences, leading to IOL explantation and cataract surgery. After topical therapy, best spectacle-corrected visual acuity was fully recovered in 9 of 11 eyes.

CONCLUSION

Iridocyclitis can occur months or years after the implantation of angle-supported phakic IOLs. No statistically significant risk factors were identified. Functional prognosis is generally good.

Surgical management of presbyopia

Presbyopia is age-related reduction in amplitude of accommodation and the loss of the ability to change the eye's focus from far to near. It is the one of the most common age-related ailment. Traditional methods such as spectacle glasses or contact lenses are still the most widely used for correction of the problem. This article is an attempt to review the surgical options available for presbyopia.