Clear lens extraction for axial myopia. An appraisal

Retinal detachment after refractive lens exchange: A narrative review

Refractive lens exchange (RLE) allows to correct ametropias and presbyopia by replacing the crystalline lens with an extended depth of focus or multifocal intraocular lens (IOL). Retinal detachment (RD) is one of the most serious adverse events after RLE. This study aimed to review the evidence related to the risk of RD after RLE and clinical outcomes. A search using PubMed and a snowball search approach was conducted to identify articles and case reports. According to the literature, the risks of RD should be considered in patients <60 years old with axial lengths >23 mm. Only nine articles reported visual acuity (VA) after RD in RLE, and only 25% of eyes had a VA > 20/40. Considering that the decrease in VA might be uniform for all types of IOLs after RD, surgeons should focus on selecting the patient to prevent RD rather than on a particular IOL optical design based on the potential risk of DR.

Clinical outcomes of implantation of posterior chamber phakic intraocular lens for pathologic and non-pathologic myopia

BACKGROUND

To compare the clinical outcomes of posterior chamber phakic intraocular lens (pIOL) implantation for non-pathological myopia and pathological myopia.

METHODS

This retrospective case series study which were conducted in Beijing Tongren Eye Center between July 2017 and Oct 2021 comprised 192 eyes of 100 consecutive patients undergoing pIOL implantation. Eyes were divided into two groups based on having pathological myopia or not. Predictability, efficacy, safety, and adverse events were compared at 6 months after pIOL implantation.

RESULTS

Our study included 86 non-pathological myopes (171 eyes, group1) and 14 pathological myopes (21eyes, group2) to analysis. The average ages were 25.5 and 33.0, respectively, and the spherical equivalent (SE) were -9.31D and -17.50D pre-operation. Six months after pIOL implantation, the SE were 0.00 and -0.50, respectively, and the refraction changes were statistically significant (P ≤ 0.05). Six months after surgery, 76.92% and 80.41% were within ± 0.50 D of the target and 92.31% and 95.88% were within ± 1.00 D. All eyes had unchanged BCVA or gained 1 or more lines in both groups and mean BCVA both improved a line 6m after operation. The efficacy index in the two groups were 0.95 and 0.88 and the safety index were 1.20, 1.33, respectively which was significantly different (P ≤ 0.05). Over the 6-month follow-up, no cataract, pigment dispersion glaucoma, pupillary block, or other vision-threatening complications happened, either.

CONCLUSIONS

The pIOL performed well for the correction of both non-pathological and pathological myopia throughout the 6-month observation period. The clinical outcomes of pIOL implantation for non-pathological myopia are essentially equivalent to those for pathological myopia.

Five Years Follow-Up of Acrysof Cachet® Angle-Supported Phakic Intraocular Lens Implantation for Myopia Correction

Purpose

The Acrysof Cachet® angle-supported phakic intraocular lens (pIOL) (Alcon Laboratories, Inc., Fort Worth, TX) is designed to correct high refractive errors in human eyes. The aim of this study was to evaluate the outcome of AcrySof Cachet® angle-supported pIOL implantation with particular regard to efficacy and safety of the implant over a 60-month follow-up period.

Design

Retrospective consecutive clinical case study.

Methods

Prior to pIOL implantation, patients had a complete ophthalmologic examination including objective and subjective refraction, uncorrected visual acuity (UCVA) and corrected distance visual acuity (CDVA), endothelial cells density (ECD), slit lamp photography, optical coherence tomography (OCT), Scheimpflug digital videokeratoscopy, optical biometry, slit lamp examination, intraocular pressure (IOP) measurement, and pupillometry. Postoperatively, patients received yearly a complete eye examination.

Results

Thirty-one eyes of 16 patients were included in this study. The mean age was 36.2 ± 8.1 years. UCVA (logMAR) improved from 1.33 ± 0.20 before surgery to 0.08 ± 0.14 one year after surgery and was 0.20 ± 0.20 five years after surgery. CDVA (logMAR) improved from 0.10 ± 0.10 before surgery to 0.05 ± 0.13 one year after surgery and was 0.04 ± 0.14 five years postoperatively. The mean percentage of endothelial cells loss (ECL) was 11.51% over the first year and 15.95% five years after surgery. There were no intraoperative complications in any of the eyes.

Conclusions

Our results up to five years after implantation of the AcrySof Cachet® angle-supported pIOL demonstrated very good outcomes in all above shown measurements, including CDVA, UCVA, and ECD. However, since major endothelial cell loss may occur in some patients with this type of pIOL, regular follow-up visits are required.

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.

Clear lens extraction for patients who are unfit for laser-assisted in situ keratomileusis and implantable contact lenses in central Indian population

Purpose:

The purpose of this study is to establish the safety of clear lens extraction (CLE) for the correction of high myopia in patients unfit for implantable contact lenses (ICLs) and laser in situ keratomileusis in the central Indian population.

Methods:

In this retrospective observational study performed at a tertiary care centre, medical records of the patients who had undergone CLE with implantation of intraocular lens (IOL) to treat high myopia were retrieved. Details of the demographic profile, surgical procedure, complications, power, and type of IOLs implanted were recorded.

Results:

The average postoperative follow-up period was 64.1 ± 4.2 months. The average postoperative spherical power was −1.4 ± 0.6 D, which was much lower than the preoperative spectacle power - 15 ± 4.4 D. There was improvement in the postoperative visual acuity (0.4 ± 0.2 logMAR) from the preoperative distant uncorrected visual acuity (0.8 ± 0.2 logMAR). No significant change in intraocular pressure (IOP) was observed. The postoperative average anterior chamber depth (ACD) (2.66 ± 0.1 mm) was significantly deeper than the preoperative ACD (2.61 ± 0.1 mm) P = 0.00. Barrage laser was required for lattice degeneration in one patient before CLE and in two patients during follow-up. Two patients (8.7%) required Nd:YAG capsulotomy for posterior capsular opacification. None of the patients had corneal decompensation, retinal detachment, or endophthalmitis.

Conclusion:

CLE with implantation of IOL is the safe procedure for correcting high myopia in patients who are unfit for ICL. None of the patient had eye loss in the follow-up period of 5 years. The low incidence of complications can be attributable to the closed chamber lens removal and implantation of IOL and prophylactic retinal treatment.

Intraocular Lens Implantation in Myopic Eyes

PURPOSE

To assess the results of posterior chamber lens implantation in myopic eyes with cataract.

METHODS

Retrospective study of postoperative results ranging from 4 to 89 months (mean 35 months) in 54 myopic patients (62 eyes with axial length of 26 mm or more) who had undergone PC IOL implantation in the Department of Ophthalmology, Medical Academy of Bydgoszcz, Poland.

OUTCOME MEASURE

Best corrected distance and near visual acuity, operative complications, early and late postoperative complications.

RESULTS

in 95% of patients with eye length 26-28 mm visual acuity of 0.5 or more was achieved. The mean postoperative spherical equivalent was -0.8 D. Posterior capsule opacification which required Nd: YAG capsulotomy developed in 19% of eyes, on average after one year of follow-up. No complications such as retinal detachment, glaucoma or corneal dystrophy were observed.

CONCLUSIONS

PC IOL implantation in myopic eyes with cataract appears to be an efficacious, satisfactory and safe procedure.

Modern Phacoemulsification and Intraocular Lens Implantation (Refractive Lens Exchange) Is Safe and Effective in Treating High Myopia

Improved efficacy, predictability, and safety of modern phacoemulsification have resulted in cataract surgery being considered as a refractive procedure. Refractive lens exchange by definition is a surgery aimed at replacing the cataractous or clear crystalline lens with an intraocular lens (IOL) in cases of high ametropia. The excellent intraocular optics of this procedure provide a better visual outcome as compared with laser refractive surgery in high myopia. With advances in technology and IOL formulas, the predictability of refractive outcome after cataract surgery in high myopes has improved. The option of addressing presbyopia using multifocal/accommodating IOLs or monovision results in patients achieving reasonable spectacle independence. The most important concern with respect to phacoemulsification in high myopia is the risk of pseudophakic retinal detachment. High myopia is an independent risk factor for retinal detachment, and recent publications have reported a much lesser risk of retinal detachment specifically attributable to phacoemulsification in high myopes, especially if a thorough posterior segment evaluation is done and patients are followed up until development of complete posterior vitreous detachment. Refractive lens exchange is an effective and safe option to correct high myopia and can significantly improve quality of life in select patients.

Comparison of Visian toric collamer lens and toric acrylic intraocular lens implantation for the treatment of myopia with astigmatism

Purpose

To compare the efficacy and outcome of phakic toric implantable collamer lens (TICL) and refractive clear lens extraction with AcrySof Toric intraocular lens (TIOL) implantation for the treatment of myopic astigmatism.

Patients and methods

This study assessed eyes with myopic astigmatism >−1 D and ≤−4 D with a spherical equivalent >10 D or <10 D if the patients were unsuitable for corneal refractive surgery. These eyes were divided into group A, in which Visian Toric ICL™ Phakic TICL was implanted, and group B, which involved clear lens extraction with implantation of an AcrySof IQ toric SN60T3-9™ IOL. The outcome and complications were evaluated.

Results

This study enrolled 63 eyes of 38 patients with a follow-up period of at least 6 months. The mean postoperative spherical equivalent was −0.19±0.31 D in group A and −0.21±0.28 D in group B (P=0.69). The mean postoperative cylinder value was −0.46±0.53 D in group A and −0.32±0.41 D in group B (P=0.35). Postoperative cylinder was <1 D in 76.47% and 79.31% of eyes in groups A and B, respectively. The mean endothelial cell count was reduced by 4.32% in group A and by 5.32% in group B (P=0.003). The mean postoperative intraocular pressure increased insignificantly in group A (P=0.22) and reduced significantly in group B (P=0.004). The complication rate was 11.76% in group A and 6.90% in group B.

Conclusion

Both procedures showed predictable results and good visual results. However, the loss of accommodation and risk of retinal complications in the TIOL group suggest that the use of TICL for myopic astigmatism is a better choice in younger patients.

Retinal detachment surgery in eyes with iris-fixated phakic intraocular lenses: Short-term clinical results

PURPOSE

To evaluate the safety of retinal detachment (RD) surgery in eyes with iris-fixated phakic intraocular lenses (pIOLs) and the efficacy of the pIOLs in correcting myopia after RD surgery.

SETTING

Single university-based tertiary referral center.

DESIGN

Retrospective case series.

METHODS

Eyes that had RD surgery (RD group) and healthy fellow eyes (control group) of the same patients were evaluated over 1 year. Surgical success, corrected distance visual acuity (CDVA), anterior chamber depth (ACD), endothelial cell density (ECD), and intraocular pressure (IOP) were assessed preoperatively and postoperatively to evaluate the safety of the surgery. The uncorrected distance visual acuity (UDVA) and spherical equivalent were assessed to evaluate the efficacy of the pIOL after RD surgery.

RESULTS

Twenty-two eyes of 11 patients were assessed. Reattachment was achieved in 10 eyes (90.9%) with the first intervention. After 1 year, the mean UDVA was 0.16 ± 0.15 logMAR (SD) in the RD group and 0.09 ± 0.12 logMAR in the control group (P=.332). The mean CDVA was 0.03 ± 0.07 logMAR in the RD group. The differences in the mean postoperative ACD and ECD between the 2 groups were not significant (P=.088 and P=.270, respectively). The mean IOP in the RD group was significantly higher than in the control group up to 1 month postoperatively; thereafter, the difference was not significant.

CONCLUSIONS

Preservation of a pIOL during RD surgery did not diminish the safety of the surgery. The efficacy of the pIOL in correcting myopia was not markedly compromised.

Vincenz Fukala (1847-1911) and the early history of clear-lens operations in high myopia

Vincenz (Wincenty) Fukala, was born in 1847 in Zolkiew at Galicia in Poland, studied medicine and ophthalmology in Vienna in 1871. He was a pioneer in systematically extracting the clear crystalline lens in young patients with high myopia. He demonstrated the benefit to this group of increased visual acuity which enabled them to work and ophthalmologists gradually began to carry out surgery in high myopes worldwide. He persisted in operating despite the vigorous opposition of several authorities but, through sheer determination he convinced skeptics of the efficacy of his surgical method of lens dissection. He performed the first lens discission in 1887 and in 1894, he had successfully treated 44 patients. The late complication of retinal detachment, which was not understood until years later, eventually led surgeons to abandon the procedure until the recent improvements in both lenticular and retinal surgery techniques that led to better prognosis.

Outcome of posterior chamber phakic intraocular lens procedure to correct myopia

PURPOSE

To assess the safety and efficacy of the implantable contact lens (ICL™) to treat myopia.

DESIGN

Clinical, retrospective, single center, non-randomized case series.

PARTICIPANTS

Sixty-nine eyes of 46 patients with myopia ranging from -3.00 to 25.00 D were included in this study.

INTERVENTION

Implantation of the ICL™.

MAIN OUTCOME MEASURES

Uncorrected Visual Acuity (UCVA), refraction, best spectacle corrected visual acuity (BSCVA), adverse events, operative and postoperative complications, subjective assessment and symptoms.

RESULTS

The mean follow-up was 12.35 ± 6.13 (SD) months (range, 6 months-32 months). At the last visit, 49.20% of eyes had 20/20 or better UCVA compared to preoperative 20/20 or better BSCVA of 31.9% of eyes; 69.23% of eyes had postoperative UCVA better than or equal to preoperative BSCVA. The mean manifest refractive cylinder was 1.93 ± 1.21 D at baseline and 1.00 ± 0.92 D postoperatively. The mean manifest refraction spherical equivalent (MRSE) was -11.70 ± 4.24 D preoperatively and -0.69 ± 1.13 D postoperatively. A total of 69.8% of eyes were within ±0.5 D of the predicted MRSE; 84.1% were within ±1.0 D, and 88.90% were within ±2.0 D. BSCVA of 20/20 or better was achieved in 64.6% of eyes postoperatively, compared to 31.9% preoperatively. Mean improvement in BSCVA was 1line. One eye (1.5%) lost ⩾2 lines of BSCVA at the last visit, whereas 20% of eyes improved by ⩾2 lines. A total of 56.92% of cases gained ⩾1 line of BSCVA and 4.62% of cases lost ⩾1 line. Four ICL lenses were removed without significant loss of BSCVA, and 2 eyes with clinically significant lens opacities were observed. Four eyes (5.8%) developed a pupillary block the first day postoperatively. One eye (1.4%) developed a hypotony and AC shallowing.

CONCLUSION

Implantation of ICL for the correction of myopia was a safe procedure with good visual and refractive results from the early postoperative period to 1 year. Long-term follow-up is required to confirm the long-term safety of this implant.

Clear lens phacoemulsification combined with vitrectomy to correct high myopia: four years of follow-up

PURPOSE

To evaluate the outcome, intraoperative and postoperative complications of refractive lens exchange (RLE) by phacoemulsification with posterior chamber intraocular lens (IOL) implantation combined with simultaneous pars plana vitrectomy (PPV) in the management of high myopia.

METHODS

This prospective study consisted of 45 eyes of 26 patients with preoperative myopia greater than -12.5 dpt. Clear lens phacoemulsification with IOL implantation surgery was combined with PPV. Main outcome measures were best-corrected visual acuity (BCVA), stability of the spherical equivalent (SE) and complications at follow-up.

RESULTS

The combined procedure of clear lens phacoemulsification combined with PPV has a favorable outcome with acceptable SE predictability and improvement in BCVA. The postoperative BCVA was 0.67 ± 0.21 compared to 0.15 ± 0.10 preoperatively (p < 0.001). The mean postoperative SE was -1.6 ± 0.9 dpt, showing a significant difference when compared with a mean value of -20.0 ± 5.2 dpt before the operation (p < 0.001). During the follow-up, all IOLs were placed stably in the bag with no capsular tear occurring and only 1 case (2.2%) developed retinal detachment.

CONCLUSION

RLE and implantation of an IOL combined with simultaneous PPV is a reasonable refractive surgery option for middle-aged patients with high myopia.

Outcomes and possible risk factors associated with axis alignment and rotational stability after implantation of the Toric implantable collamer lens for high myopic astigmatism

AIM

To assess the visual outcomes and possible risk factors associated with axis alignment and rotational stability after implantation of Toric implantable collamer lens (TICL) for the correction of high myopic astigmatism.

METHODS

In this prospective, nonrandomized clinical study, 54 consecutive eyes of 29 patients with high myopic astigmatism received TICL implantation. To evaluate postoperative axis deviation from the intended axis, a digital anterior segment photograph was taken. The ultrasound biomicroscopy(UBM) was used to observe footplate-position.

RESULTS

After mean follow-up of 8.6 months, mean manifest refractive cylinder (MRC) decreased 79.3% from (-1.88±1.49)D preoperatively to (0.39±0.61)D postoperatively. MRC within 1.00 D occurred in 68.5% (37/54) of eyes, whereas 48.1% (26/54) had MRC within 0.50 D. Mean manifest refraction spherical equivalent (MRSE) changed from (-12.08±4.22)D preoperatively to (-0.41±0.61)D postoperatively. Uncorrected binocular vision of 20/20 or better occurred in 72.2% (39/54) of patients compared with binocular best-corrected visual acuity (BCVA) of 20/20 or better in 44.4% (24/54) preoperatively. The mean difference between intended and achieved TICL axes was (6.96±8.37)°. Footplates of TICLs were in the ciliary sulcus in 22 eyes (46.3%), below the ciliary sulcus in 32 eyes (53.7%). The angle of TICL rotation had significant correlation with the footplates-position (t=2.127; P=0.045) and the postoperative TICL vaulting (r=-0.516; P=0.000).

CONCLUSION

The results of our study further support the safety, efficacy and predictability of TICL for the correct high myopic astigmatism. The footplate-position of TICL and vault value should be taken into consideration as two possible risks factors for TICL rotation.

Comparison of clear lens extraction and collamer lens implantation in high myopia

Aim:

To compare the outcomes of clear lens extraction and collamer lens implantation in high myopia.

Patients and methods:

Myopic patients younger than 40 years old with more than 12 diopters of myopia or who were not fit for laser-assisted in situ keratomileusis were included. Group 1 comprised patients undergoing clear lens extraction and Group 2 patients received the Visian implantable collamer lens. Outcome and complications were evaluated.

Results:

Postoperative best corrected visual acuity was −0.61 ± 0.18 in Group 1 and 0.79 ± 0.16 in Group 2. In Group 1, 71.4% achieved a postoperative uncorrected visual acuity better than the preoperative best corrected visual acuity, while only 51.8% patients achieved this in Group 2. Intraocular pressure decreased by 12.55% in Group 1, and increased by 15.11% in Group 2. Corneal endothelial cell density decreased by 4.47% in Group 1 and decreased by 5.67% in Group 2. Posterior capsule opacification occurred in Group 1. In Group 2, lens opacification occurred in 11.11%, significant pigment dispersion in 3.7%, and pupillary block glaucoma in 3.7%.

Conclusion:

Clear lens extraction presents less of a financial load up front, and less likelihood of the need for a secondary intervention in the future. Clear lens extraction is a more viable solution in developing countries with limited financial resources.

Refractive surgery: through the looking glass

Historically, surgical procedures designed to change the refractive power of the cornea have been controversial at their inception, gaining acceptance only with time and study. From intraocular lenses to corneal remodelling with the excimer laser, and numerous procedures in between, including radial keratotomy, epikeratophakia, incisional keratotomy for astigmatism, and hydrogel and polysulfone implants, ophthalmologists have balanced the risks and benefits for their patients to produce the maximum benefit at the least cost. The present status and future potential of each of these are assessed as they appear today. There is no question that progress will continue, and that our patients will be the beneficiaries of our ongoing interest in improving older procedures and developing new techniques for the correction of refractive errors.

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.

Retinal Detachment in Myopic Eyes After Phakic Intraocular Lens Implantation

PURPOSE

To analyze the risk of retinal detachment in highly myopic patients who underwent implantation of phakic intraocular lenses (PIOLs).

METHODS

In a retrospective, non-comparative, interventional case series, the occurrence of retinal detachment was analyzed in 522 consecutive highly myopic eyes (323 patients) that underwent PIOL implantation. Treatment and results were reviewed. Parameters evaluated were best corrected visual acuity before and after retinal detachment surgery and time between refractive surgery and retinal detachment.

RESULTS

Fifteen (2.87%) eyes presented with retinal detachment after PIOL implantation, with a mean time between surgery and detachment of 24.4 +/- 24.4 months (range: 1 to 92 months). The risk of retinal detachment in patients with high myopia corrected by PIOL implantation was 0.57% at 3 months, 1.64% at 12 months, 2.73% at 36 months, and 4.06% at 92 to 145 months (Kaplan-Meier analysis). A comparative study between the group of patients with retinal detachment and the remaining patients without retinal detachment was performed. Differences were found in axial length (30.65 +/- 1.97 vs 29.51 +/- 2.02; P=.028, one factor-analysis of variance test).

CONCLUSIONS

The risk of retinal detachment in eyes implanted with phakic lenses for the correction of high myopia is higher in eyes with axial length >30.24 mm.

Phakic Intraocular Lenses

An analytical review of the data available in the field of phakic intraocular lens implantation was conducted. Particular attention was paid to the more critical issues of intraocular lens sizing and safety guidelines. A comprehensive, competitive analysis of different implantation sites, intraocular lens model designs, and safety guidelines has been included. Specialized biometry techniques, such as very high frequency ultrasound and Scheimpflug imaging, have been reviewed, and a critical review of commercial claims regarding intraocular lens technologies has been included. Clinical studies of phakic intraocular lenses demonstrate increasing promise for the correction of refractive errors not amenable to mainstream excimer laser refractive surgery. The main issues currently revolve around adequate lens design (VHF ultrasound study suggests that custom-design and sizing may be the most effective and safest approach for every phakic IOL model), because these devices will be required to remain physiologically inert and anatomically compatible with internal ocular structures and relations for several decades. The possibility of safe removing or exchanging the IOL should remain a feasible option over time. It is of utmost importance that we continue to critically evaluate current encouraging short-term outcomes, which are being extrapolated to the longer term by ongoing high resolution imaging and monitoring of the anatomical and functional relations of implanted phakic IOLs.

Artisan Toric Phakic Intraocular Lens for Correction of Astigmatism

PURPOSE

To assess the safety and efficacy of implanting Artisan toric phakic intraocular lenses (PIOLs) (Ophtec BV, Groningen, The Netherlands) in eyes with high degrees of compound myopic, hyperopic, and mixed astigmatism.

METHODS

Twenty-five eyes (20 patients) presenting with high astigmatism were implanted with Artisan toric PIOLs and followed for 1 year. Group 1 included 8 eyes (myopic astigmatism), group 2 included 9 eyes (hyperopic astigmatism), and group 3 included 8 eyes (mixed astigmatism).

RESULTS

In the myopic astigmatism group, 8 (100%) of 8 eyes had preoperative uncorrected visual acuity (UCVA) of < or = 20/50, and at 6-month follow-up, 5 (62.5%) of 8 eyes had UCVA of > or = 20/40 (P = .005). In this group, 75% of eyes were within +/- 1.00 diopter (D) of the intended correction. In the hyperopic astigmatism group, 8 (88.9%) of 9 eyes had preoperative UCVA of < or = 20/40, and at 6-month follow-up, 6 (66.6%) of 9 eyes had UCVA of > or = 20/32 (P = .199). Approximately 77.8% of eyes were within +/- 1.00 D of the intended correction. In the mixed astigmatism group, 8 (100%) of 8 eyes had preoperative UCVA of < or = 20/50, and at 6-month follow-up, 6 (87.5%) of 8 eyes had UCVA of > or = 20/40 (P = .007). In this group, 87.5% of eyes were within +/- 1.00 D of the intended correction. The safety index of the procedure was 1.6, 1.3, and 1.3 in the myopic, hyperopic, and mixed astigmatism groups, respectively. The efficacy index of the procedure was 1.2, 1.0, and 1.0 in the myopic, hyperopic, and mixed astigmatism groups, respectively.

CONCLUSIONS

Artisan toric PIOLs are safe for the correction of high degrees of astigmatism associated with myopic or hyperopic spherical refractive defect.

Refractive lens exchange combined with pars plana vitrectomy to correct high myopia

PURPOSE

To describe the results of refractive lens exchange (RLE) combined with simultaneous pars plana vitrectomy (PPV) in the management of severe myopia.

METHODS

This retrospective study comprised 14 eyes of eight patients who had RLE to treat myopia of -19.0+/-5.4 diopters (D). Phacoemulsification, posterior chamber intraocular lens (IOL) implantation, and standard three-port vitrectomy were performed. Mean postoperative follow-up time was 30 months (range 12-49).

RESULTS

The postoperative best-corrected visual acuity (BCVA) was 0.68+/-0.23 compared to 0.37+/-0.24 preoperatively. There was no postoperative decrease in visual acuity in any eye. Mean postoperative spherical equivalent was -0.7 D (+/-1.6). At 30 months mean follow-up time, the spherical equivalents of nine eyes (64.3%) were within +/-1 D of emmetropia. There was no significant change in astigmatism due to operative procedures. During the 30 months follow-up period three eyes (21.4%) required neodymium : yttrium-aluminium-garnet (Nd : YAG) capsulotomy for posterior capsule opacification. No retinal detachments or cases of cystoid macular oedema (CME) were observed during the follow-up.

CONCLUSION

RLE was effective in correcting severe myopia. The simultaneously performed PPV may reduce the risk of postoperative retinal detachment. This was a pilot study, to draw definitive conclusions a prospective study has to be initiated.

Phakic refractive lens implantation in high myopic patients: one-year results

PURPOSE

To evaluate the efficacy and safety of implantation of a new posterior chamber phakic refractive lens (PRL, Ciba Vision Surgical) in highly myopic eyes.

SETTING

Department of Ophthalmology, Medical School, University of Crete, Vardinoyannion Eye Institute of Crete, Crete, Greece.

METHODS

Thirty-four myopic eyes of 19 patients were treated for high myopia with implantation of a silicone PRL in the posterior chamber. Mean patient age was 29.0 years +/- 7.9 (SD) (range 18 to 44 years). Manifest refraction in spherical equivalent (MR), uncorrected (UCVA) and best corrected (BCVA) visual acuity (decimal scale), intraocular pressure, higher-order aberrations (root-mean-square [RMS] wavefront error measured with a Shack-Hartmann wavefront sensor WASCA analyzer [Carl Zeiss, Meditec]), possible complications, and subjective symptoms were evaluated.

RESULTS

Phakic refractive lenses were successfully implanted in all eyes. Mean follow-up was 17.17 +/- 3.76 months (range 12 to 24 months). There was a statistically significant reduction in the MR (from -14.70 D +/- 2.65 D [range -20.75 D to -10.50 D] to -0.61 D +/- 0.89 D [range -2.25 D to 1.00 D]) (P<.001). Twenty-seven (79%) and 15 eyes (44%) were within +/-1.00 D and +/-0.50 D of target refraction, respectively. Mean UCVA significantly improved (from counting fingers to 0.62 +/- 0.28 (range 0.08 to 1.20) (P<.001). Mean BCVA also improved from 0.70 +/- 0.24 (range 0.10 to 1.00) to 0.85 +/- 0.24 (range 0.10 to 1.20) (P<0.001). Overall, there was a mean increase in BCVA of 1.5 +/- 1.5 lines (range loss of 2 lines to gain of 5 lines). There was no statistically significant difference in higher-order aberrations after PRL implantation (pre-PRL RMS: 0.18 microm +/- 0.08 microm [range 0.09 microm to 0.38 microm]; post-PRL RMS: 0.21 microm +/- 0.08 microm; [range 0.05 microm to 0.38 microm]) (P =.12).

CONCLUSION

The PRL showed encouraging results in treating high myopia. Additional patients and longer follow-up period are needed to detect the long-term efficacy and safety of this refractive lens.

Phakic intraocular lenses to correct high myopia

PURPOSE

To evaluate the feasibility and safety of using phakic intraocular lenses (IOLs) to correct high myopia by comparing 3 IOL models: Adatomed, Staar, and Artisan.

SETTING

La Fe University Hospital, Department of Ophthalmology, and the Fundación Oftalmológica del Mediterráneo, Valencia, Spain.

METHODS

In this prospective comparative study, a phakic IOL was implanted in 217 highly myopic eyes (118 patients). Fifty-nine eyes received an Adatomed IOL, 21 eyes a Staar IOL, and 137 eyes an Artisan IOL. The mean preoperative spherical equivalent was -15.39 diopters (D) +/- 2.83 (SD), -16.00 +/- 5.05 D, and -16.17 +/- 2.75 D in the Adatomed, Staar, and Artisan groups, respectively. The mean follow-up was 32.4 months (range 19 to 46 months) in the Adatomed group, 18.3 months (range 11 to 21 months) in the Staar group, and 121.4 months (range 38.4 to 154.3 months) in the Artisan group. At the follow-up examinations, intraocular pressure (IOP), IOL pigment deposits, cataract formation, and visual acuity were evaluated.

RESULTS

The best corrected and uncorrected visual acuities improved in all eyes. No significant differences in visual acuity improvement were observed with the 3 materials, although the improvement was somewhat greater in eyes with the Artisan and Staar IOLs. The difference in mean IOP between preoperatively and the last follow-up examination was 1.5 mm Hg in the Staar group, 1.3 mm Hg in the Adatomed group, and 1.7 mm Hg in the Artisan group (P =.36, P =.26, and P =.32, respectively). The incidence of pigment deposits was similar in the Adatomed and Staar groups, with deposits in 32 eyes (54.23%) and 8 eyes (38.1%), respectively. Anterior cataract formation was higher in the Adatomed group (44.06%) than in the Staar group (9.52%); nuclear cataract developed in 2 Adatomed eyes (1.46%) only.

CONCLUSIONS

There was a higher incidence of anterior subcapsular cataract formation in the Adatomed group than in the Staar group. Delayed cataract development and the cataract type in patients with Artisan IOLs indicate that age and axial length may be prognostic factors. Factors such as IOL design, material, and placement probably affect cataract formation in eyes with posterior chamber IOLs for high myopia, particularly the Adatomed IOL.

Clear lens extraction for the correction of high myopia

OBJECTIVE

To evaluate the postoperative outcomes and intraoperative and postoperative complications of clear lens extraction (CLE) with posterior chamber intraocular lens (IOL) implantation in highly myopic eyes.

DESIGN

Retrospective case series.

PARTICIPANTS

One hundred seven patients (190 eyes) who had undergone CLE with posterior chamber IOL implantation and who had been observed for at least 3 years after surgery.

METHODS

Medical records of patients who had undergone CLE with posterior chamber IOL implantation to treat high myopia (axial length >26.00 mm) over 7 years (January 1990 to December 1996) were reviewed. Visual acuity and refractive error were assessed before and after surgery, and perioperative, intraoperative, and postoperative complications were recorded.

MAIN OUTCOME MEASURES

Axial length, preoperative and final best spectacle-corrected visual acuity (BSCVA), preoperative and postoperative spherical equivalent (SE), argon laser treatments, surgical complications, neodymium:yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy, retinal detachment (RD), time from surgery or Nd:YAG capsulotomy to RD, subfoveal choroidal neovascularization (CNV), and follow-up period.

RESULTS

The mean postoperative follow-up period was 4.78 years (range, 3.10-8.03 years). Final BSCVA was better than preoperative BSCVA in 159 eyes (83.68%), equal in 24 eyes (12.63%), and worse in 7 eyes (3.68%). Postoperative BSCVA was 20/40 or better in 136 eyes (71.60%) vs. 52 eyes (27.36%) before surgery (P<0.001). The mean final postoperative SE was -1.22 diopters. The risk of Nd:YAG laser capsulotomy was 77.89%. The incidence of RD was 2.10%; retinal reattachment was achieved in all cases, and none of these eyes had worse final BSCVA than before surgery. Subfoveal CNV developed in 4 eyes (2.10%) of 3 patients; all of these eyes presented with a macular lacquer crack.

CONCLUSIONS

Clear lens extraction with posterior chamber IOL implantation has good outcomes with acceptable predictability and improvement in best-corrected visual acuity. During follow-up, patients tended to remain stable, and the risk of retinal detachment was low. We attribute our favorable results to careful patient selection and follow-up.

Cataract surgery as a risk factor for retinal detachment in very highly myopic eyes

PURPOSE

To evaluate the incidence of retinal detachment (RD) after cataract surgery performed by phacoemulsification in very highly myopic eyes.

DESIGN

Retrospective, paired-eye, case-control trial.

PARTICIPANTS AND INTERVENTION

We assessed the development of RD in 930 eyes from 930 subjects (mean age = 62.5 +/- 8.5 years) affected by very high myopia (between -15 and -30 diopters) undergoing cataract surgery after uncomplicated phacoemulsification (cataract-subjected [CS] eyes). Fellow eyes served as controls. Follow-up was 36 months.

MAIN OUTCOME MEASURE

Detachment of the retina.

RESULTS

Retinal detachment was observed in 8.0% of CS eyes compared with 1.2% of control eyes (P<0.01, chi-square test). In CS eyes, posterior RD was most common (52.7% of eyes with RD). In control eyes, peripheral detachments with or without macular involvement were most common (47.3% of eyes with RD).

CONCLUSION

Cataract surgery, despite the use of a safe technique such as phacoemulsification, increases the risk of RD development in very highly myopic eyes.

Outcome after treatment of ametropia with implantable contact lenses

OBJECTIVE

To evaluate long-term results after insertion of implantable contact lenses (ICLs) in phakic eyes.

DESIGN

Prospective, noncomparative, interventional case series.

PARTICIPANTS

Seventy-five phakic eyes (65 myopic, 10 hyperopic eyes) of 45 patients aged 21.7 to 60.6 years were included.

INTERVENTION

STAAR Collamer Implantable Contact Lenses (STAAR Surgical Inc., Nidau, Switzerland) were implanted for correction of high myopia and hyperopia.

MAIN OUTCOME MEASURES

Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and intraocular pressure (IOP) were determined. Presence of lens opacification and the distance between the ICL and the crystalline lens were assessed by slit-lamp examination before surgery and at 1, 3, 6 months, and yearly after lens implantation.

RESULTS

Preoperative mean spherical equivalent was -16.23+/-5.29 diopters (D) for myopic eyes and +7.88 +/-1.46 D for hyperopic eyes. After ICL implantation, mean residual refractive error was -1.77+/-2.17 D in myopic patients and +0.44+/-0.69 D in hyperopic patients. Preoperative mean UCVA was Snellen 0.03+/-0.03 for myopic patients and Snellen 0.12+/-0.16 for hyperopic patients. Preoperative mean BCVA was Snellen 0.49+/-0.23 for myopic patients and Snellen 0.82+/-0.23 for hyperopic patients. After ICL implantation, mean UCVA up to the end of individual observation time was Snellen 0.36+/-0.36 for myopic patients and Snellen 0.58+/-0.28 for hyperopic patients. Mean BCVA was Snellen 0.73+/-0.26 for myopic and Snellen 0.80+/-0.24 for hyperopic patients. Mean preoperative IOP was 14.2+/-2.7 mmHg, and mean postoperative IOP was 13.46+/-2.1 mmHg over all follow-up investigations. The main complication was the development of subcapsular anterior opacifications of the crystalline lens in 25 eyes (33.3%), 2 of which showed direct contact to the ICL. Eleven eyes (14.7%) were stable in opacification and 14 eyes (18.7%) had progressive opacifications. The median time to opacification was 27.1 months. In 8 patients (10.7%), the subjective visual impairment mandated cataract surgery.

CONCLUSIONS

The most significant long-term complication after ICL implantation is the formation of opacifications of the crystalline lens with the risk of the necessity of subsequent cataract surgery (10.7%). Old age, female gender, and contralateral opacification are independent significant risk factors for early formation of opacifications in this patient group.

Pseudophakic retinal detachment

Pseudophakic retinal detachment is a rare, but potentially serious, complication of cataract surgery. The incidence of pseudophakic retinal detachment following current surgical techniques of cataract extraction, including extracapsular cataract extraction by nuclear expression and phacoemulsification, is lower than that found after intracapsular cataract extraction. The risk of pseudophakic retinal detachment appears to be increased in myopic patients, in those patients in whom vitreous loss had occurred at the time of cataract surgery, and in patients undergoing Nd:YAG posterior capsulotomy. Most cases present to the clinician when the macula is already detached and the central vision is affected. When evaluating patients with pseudophakic retinal detachment, the fundal view is often impaired by anterior or posterior capsular opacification, reflections related to the intraocular lens, or poor mydriasis. Scleral buckling, pneumatic retinopexy, and primary pars plana vitrectomy, with or without combined scleral buckling, are the surgical techniques used to treat pseudophakic retinal detachment. Anatomical success rates are high after vitreo-retinal surgery for pseudophakic retinal detachment, although a smaller proportion of patients recover good vision following surgery.

Retinal detachment after cataract extraction and refractive lens exchange in highly myopic patients

PURPOSE

To assess the refractive effects and incidence of postoperative complications in patients with high myopia after cataract extraction.

SETTING

University Eye Clinic, Trieste, Italy.

METHODS

This noncomparative retrospective study comprised all eyes (N = 388) having cataract extraction and implantation of an intraocular lens with a power less than 11.0 diopters (D) between 1986 and 1999. The preoperative and postoperative refractions; preoperative, postoperative, and final best corrected visual acuity (BCVA); and postoperative complications were analyzed. The mean follow-up was 47.16 months +/- 32.83 (SD) (range 8 to 146 months).

RESULTS

Phacoemulsification was performed in 237 eyes, extracapsular cataract extraction in 147 eyes, and intracapsular cataract extraction in 4 eyes. The mean preoperative BCVA was 0.20 +/- 0.21 and the mean postoperative BCVA, 0.58 +/- 0.32. At the final evaluation, the mean BCVA was 0.50 +/- 0.33. The mean refraction was -15.95 +/- 5.86 D preoperatively and -2.00 +/- 1.62 D postoperatively. One eye (0.26%) developed a retinal detachment postoperatively. Of the 127 eyes (32.73%) having a neodymium:YAG laser capsulotomy for posterior capsule opacification, 1 had a macular retinal hole. Posterior detachment of the vitreous occurred in 78.6% of cases. Peripheral retinal photocoagulation was required in 8 cases postoperatively.

CONCLUSION

Refractive lens exchange led to good functional results and a low incidence of postoperative complications and can thus be regarded as a viable technique to correct high myopia associated with cataract. However, further study is required before it can be routinely recommended for the correction of high myopia in eyes with a transparent crystalline lens.

Phakic intraocular lenses and refractory lensectomy for myopia

Phakic intraocular lens implantation (IOLs) and clear lens extraction for high to extreme myopia have grown in popularity recently as a consequence of potentially unsatisfactory results with corneal refractive surgery in higher ranges of refractive errors. The refractive outcome of these alternative modalities has been encouraging to date, yet the potential for significant complications exists. Current evidence shows that the risk of retinal detachment after clear lens extraction for myopes is high. Trials with angle-supported phakic IOLs revealed unacceptable rates of pupillary ovalization, IOL rotation, and endothelial cell loss. Iris-fixated and posterior chamber phakic IOLs have proven sufficient safety, but long-term follow-ups of current cohorts are still to be awaited. The implantation of either of the latter two phakic IOLs followed by laser in situ keratomileusis or photorefractive keratectomy (bioptics) provides another option in refractive surgery for high ametropia.

Implantable contact lens for high myopia

PURPOSE

To evaluate the efficacy, safety, and biocompatibility of a collagen polymer implantable contact lens (ICL) (Staar Collamer) as a posterior chamber phakic intraocular lens (IOL) to correct high myopia.

SETTING

Departments of Ophthalmology, Helsinki University Central Hospital, Helsinki, and Tampere University Hospital, Tampere, Finland.

METHODS

A Staar Collamer posterior chamber phakic IOL was implanted in 38 eyes of 22 patients with a mean age of 39 years (range 24 to 54 years). The mean preoperative myopia was -15.10 diopters (D) (range -7.75 to -29.00 D). Surgical implantation was performed through a 3.0 mm clear corneal sutureless incision using paraocular anesthesia. The patients were followed clinically up to 3 years. The mean follow-up was 13.6 months (range 6 to 24 months) for refractive data and 22.3 months (range 6 to 35 months) for complications. The possible inflammatory response to the ICL was measured using a laser flare meter in 12 eyes.

RESULTS

Postoperatively, all eyes had a significant increase in uncorrected visual acuity, allowing all but 3 patients (5 eyes) to manage most activities without spectacles. The mean spherical equivalent refraction at the last examination was -2.00 D +/- 2.48 (SD) (range +0.13 to -13.00 D), within +/-1.00 D of the targeted refraction in 31 eyes (81.6%) and within +/-0.50 D in 27 eyes (71.1%). In eyes in which the preoperative myopia was less than -18.00 D (n = 28), the achieved refraction was within +/-1.00 D of the intended refraction in 27 eyes (96.4%) and within +/-0.50 D in 24 eyes (85.7%). The refraction remained stable with a statistically insignificant change (P >.05) at each interval during the follow-up. The best corrected visual acuity (BCVA) improved by 1 or more lines in 23 of 32 eyes (71.9%) at 1 year. Two eyes (6.3%) lost 1 line of BCVA. Laser flare photometry showed normal aqueous flare values (11.71 +/- 6.61 photon counts/ms) in the 12 eyes measured at least 6 months after ICL implantation. Pupillary block glaucoma requiring surgical intervention occurred in 3 patients (7.9%). One patient (2.6%) developed cataract 1.5 years after ICL implantation; both ICLs were removed, and the refractive errors were corrected by lensectomy and implantation of low-power posterior chamber IOLs. One patient (2.6%) showed progression of dry macular degeneration at 17 months.

CONCLUSION

At 1 year, ICL implantation had good visual and refractive results with excellent biocompatibility. Long-term follow-up is required to confirm that significant complications do not occur in most patients over time.

Piggyback implantation using the AMO array multifocal intraocular lens

Piggyback intraocular lens (IOL) implantation allows refractive correction in cases in which the IOL power requirement exceeds that of the available lenses. By combining a piggyback technique with the use of a multifocal IOL, one can obtain the optical advantages of both, achieving high-quality visual acuity for distance and near vision and reducing the optical aberrations of extremely high-powered single IOLs. We report 5 hyperopic patients (6 eyes) who had phacoemulsification and in-the-bag implantation of 2 foldable IOLs in the bag, a silicone multifocal IOL placed in front of a silicone monofocal IOL. Good results were obtained in near and distance uncorrected visual acuities, and patient satisfaction was excellent in all cases. However, in 2 cases, the anteriorly placed IOL was exchanged because of incorrect power calculation. Piggyback IOL implantation with a multifocal lens appears to be a safe, efficient procedure and a good refractive solution.

Early Rhegmatogenous Retinal Detachment Following Laser in situ Keratomileusis for High Myopia

PURPOSE

Four eyes had early rhegmatogenous retinal detachment within 3 months of laser in situ keratomileusis (LASIK) for correction of high myopia using the microkeratome, Clear Corneal Molder.

METHODS

In two eyes, retinal detachment resulted from horseshoe tears, one occurring in an otherwise normal region of the retina and the other at the margin of an area of lattice degeneration detected during preoperative examination. The first eye was treated with retinopexy using a 287 encircling scleral exoplant, drainage of subretinal fluid, and laser photocoagulation by indirect ophthalmoscopy. The other eye was treated with pneumatic retinopexy and cryotherapy. In the other eyes, retinal detachment was the result of giant tears with no evidence of prior retinal degeneration. These eyes were treated with pars plana vitrectomy, fluid-gas exchange with 15% perfluoropropane (C3F8), endolaser photocoagulation, and a 42 encircling scleral exoplant.

RESULTS

After treatment, the first two eyes achieved spectacle-corrected visual acuity of 20/40. In the last two eyes, final spectacle-corrected visual acuity was 20/400 in one eye and light perception in the other.

CONCLUSIONS

Although no cause-effect relationship between LASIK and retinal detachment can be stated, these cases suggest that LASIK may be associated with retinal detachment, particularly in highly myopic eyes. Further studies are necessary to determine high-risk patient characteristics.

Retinal detachment after clear lens extraction for high myopia: seven-year follow-up

OBJECTIVE

To prospectively evaluate the incidence of complications, particularly retinal detachment, 7 years after clear lens extraction (CLE) for myopia greater than -12 diopters (D).

DESIGN

Extended follow-up of noncomparative case series.

PARTICIPANTS

Fifty-two eyes of 30 patients with preoperative myopia greater than -12 D, best-corrected visual acuity (BCVA) of 20/100 or better, and intolerance of contact lenses.

INTERVENTION

Patients with lattice degeneration, retinal tear, or hole underwent photocoagulation before CLE. The authors performed phacoemulsification through a 3.2-mm-wide incision using primary irrigation and aspiration, widened the incision to 6.5 mm, and implanted a one-piece polymethyl methacrylate intraocular lens (IOL).

MAIN OUTCOME MEASURES

The BCVA, uncorrected visual acuity (UCVA), stability of spherical equivalent (SE), neodymium:YAG (Nd:YAG) capsulotomy rate, and complications (especially retinal detachment).

RESULTS

At 7 years, the SEs of 29 eyes (59.1%) were within +/-1.0 D of emmetropia and 42 eyes (85.7%) were within +/-2.0 D. Mean SE was -1.01 D (+/-0.94). At 7 years, mean UCVA was 20/80 compared with 20/66 at 1 year. BCVA and UCVA were better in eyes with open capsules versus intact capsules. During the 7 years, 30 eyes (61.2%) required capsulotomy for opacification. Mean time for capsulotomy was 48.4 months after CLE. The authors performed ten argon laser retinal treatments after surgery, with all but one in the first postoperative year. The overall incidence of posterior vitreous detachment was 16.3%. The incidence of retinal detachment during the 7 years was 4 of 49 eyes, or 8.1% (vs. 2.0% at 4 years). One patient had bilateral retinal detachments.

CONCLUSION

Despite advances in surgical technique, retinal detachment remains a major concern after CLE for high myopia. In the authors' series, the incidence of retinal detachment after CLE was nearly double that estimated for persons with myopia greater than -10 D who do not undergo surgery. Although CLE has advantages, including rapid and predictable visual rehabilitation, stable refraction, the ability to replace the IOL, and often superb optical quality with no irregular astigmatism, it is invasive and can result in severe vision loss. Long and continuous follow-up of the outcomes of CLE for high myopia is absolutely necessary before the authors can consider CLE as a routine option for patients with high myopia.

Phacoemulsification and modern cataract surgery

The techniques and results of cataract surgery have changed dramatically during the past three decades. In the USA, we have moved from intracapsular cataract extraction as the preferred technique to almost exclusively extracapsular techniques. Smaller incisions have become the standard, with phacoemulsification now being the method of choice for most surgeons. Along with these advances have come improved intraocular lens materials and designs, especially well suited for use with smaller incisions. Phacoemulsification as a method to remove the cataractous lens was first proposed more than 20 years ago. Advances in techniques and equipment have led to a dramatic increase in the popularity of phacoemulsification with increased safety and efficiency. Viscoelastic agents have been developed synchronously with modern phacoemulsification techniques, playing an integral role in the success of this new technology. Improved surgical techniques for removing the anterior lens capsule have decreased the incidence of both intraoperative and postoperative capsular complications. Nucleus removal, formerly performed primarily in the anterior chamber, is now performed in the posterior chamber, decreasing damage to the corneal endothelium. Improved wound construction allows many wounds to be left unsutured, and smaller wounds allow shorter recovery time and greater intraoperative control and safety. Intraocular lenses can have smaller optic sizes and still maintain accurate centration. Foldable intraocular lenses can take advantage of the smaller incision, even further shortening the time to visual recovery. Continual evolution of this technology promises to further improve patient outcomes after cataract surgery.

Endothelial study of iris-claw phakic lens: four year follow-up

PURPOSE

To study quantitative and morphometric endothelial changes in phakic eyes implanted with the Worst iris-claw lens to correct high myopia.

SETTING

Department of Ophthalmology, University Hospital "La Fe", Valencia, Spain.

MATERIAL AND METHODS

This retrospective study involved 111 phakic eyes (73 patients) implanted with the Worst iris-claw lens. Noncontact specular microscopy and computer-assisted analysis was performed preoperatively and 6 months and 1, 2, 3, and 4 years postoperatively.

RESULTS

The mean cell loss was 3.85% at 6 months, 6.59% at 1 year, 9.22% at 2 years, 11.68% at 3 years, and 13.42% at 4 years. At 2 years, the hexagonality and coefficient variation in cell size were close to the preoperative levels. No major complications were seen; early postoperative corneal touch required intraocular lens (IOL) removal in 1 case (0.9%). Four eyes (3.6%) needed a reoperation because of poor IOL fixation (2 eyes), traumatic subluxation of the IOL (1 eye), and miscalculation of the IOL power (1 eye).

CONCLUSIONS

Although there was a slight progressive cell loss after IOL implantation, the morphometric changes recovered and were close to the preoperative levels. This suggests that endothelial damage occurred primarily during the surgical procedure.

Staar Collamer posterior chamber phakic intraocular lens to correct myopia and hyperopia

PURPOSE

To evaluate the efficacy, safety, stability, and predictability of implanting a collagen polymer (Staar Collamer), posterior chamber phakic intraocular lens (IOL) to correct myopia and hyperopia.

SETTING

Centre for Advanced Refractive Eye Surgery at the BMI Alexandra Hospital, Cheadle, Manchester, United Kingdom.

METHODS

A Staar Collamer posterior chamber phakic IOL was implanted in 25 eyes of 14 patients with a mean age of 37.9 years (range 20 to 50 years). Seven patients were men and seven, women. Sixteen were myopic and 9, hyperopic. Before treatment, each patient had a thorough evaluation including refractive, general, ocular, and social and personal histories. The examination included visual acuity, refraction, tonometry, topography, biometry, biomicroscopy, pupil size in dim illumination, and posterior segment evaluation by a vitreoretinal specialist. Patients were informed about the surgical process and expected outcome, their own expectations were discussed, and their consent to surgery was obtained. Surgical implantation was performed through a less than 3.0 mm clear corneal sutureless incision using brief general anesthesia on a day-case surgical basis.

RESULTS

At 3 months postoperatively, all eyes had a significant increase in uncorrected visual acuity, allowing all but two patients (three eyes) to manage most activities without spectacles. Adjustment by incisional corneal surgery was planned for undercorrected myopic eyes (n = 3). Pupil block glaucoma and pigment deposits occurred in one patient each.

CONCLUSION

In this short-term study, the posterior chamber phakic IOL was predictable, safe, and efficacious in the correction of myopic and hyperopic refractive errors, with good refractive stability. Long-term follow-up is required to validate that the absence of significant complications in most patients is a lasting phenomenon.

Posterior Chamber Phakic Intraocular Lens for Myopia of -8 to -19 Diopters

PURPOSE

To examine the efficacy, predictability, stability, and safety of posterior chamber phakic intraocular lens (IOL) implantation in patients with extreme myopia.

METHODS

We analyzed the results of 124 eyes that received a posterior chamber hydrogel collagen plate phakic IOL (Staar Collamer Implantable Contact Lens, ICL) for the correction of their myopia. The target postoperative spherical equivalent refraction was emmetropia. Mean follow-up was 11 months (range 1 to 36 mo).

RESULTS

The mean preoperative spherical equivalent refraction was -13.38 +/- 2.23 D (range, -8.50 to -18.63 D). Mean postoperative spherical equivalent refraction at last examination was -0.78 +/- 0.87 D (range, +1.63 to -3.50 D), with 69% (86 eyes) within +/-1.00 D and 44% (55 eyes) within +/-0.50 D of emmetropia. The refraction remained stable with a statistically insignificant change (p > 0.05 at each interval) during follow-up. A gain of two or more lines of spectacle-corrected visual acuity was seen in 36% (45 eyes) at last examination. One eye (0.8%) lost two or more lines of spectacle-corrected visual acuity from a retinal detachment.

CONCLUSION

Posterior chamber phakic IOL implantation with the Staar Collamer plate lens is an effective and safe method for reducing or correcting myopia between -8 and -19 D. Gains in spectacle-corrected visual acuity were common, and results suggested good refractive stability. Improvements in phakic IOL power calculation formulas are needed to improve the predictability of refractive outcome.

Clear Lensectomy and Intraocular Lens Implantation for Hyperopia from +7 to +14 Diopters

BACKGROUND

Our results of clear lens extraction and intraocular lens implantation to correct hyperopia from +6.75 to +13.75 D are presented, as well as evaluation of two intraocular lens calculation formulae.

METHODS

Clear lens extraction and posterior chamber intraocular lens implantation was performed in 35 normally sighted eyes of 21 patients with a mean baseline hyperopic spherical equivalent refraction of +9.19 +/- 0.34 D (range +6.75 to +13.75 D). The refractive goal was -1.50 D, using the SRK II formula in 17 eyes and the SRK-T formula in 18 eyes. Follow-up was up to 5 years.

RESULTS

Mean uncorrected visual acuity after surgery was 0.8 (range 0.5 to 1.0). Stability of refraction was noted from the second month after surgery. No eyes lost any lines of spectacle-corrected visual acuity. Using the SRK II formula, 100% of eyes were within +/-1.00 D of emmetropia and with the SRK-T formula, 83.3% for a combined 91.4% of eyes within +/-1.00 D of emmetropia. One eye required intraocular lens exchange and another eye required photorefractive keratectomy for myopia. Both procedures were necessitated by an intraocular lens miscalculation of more than +/-2.00 D. Nineteen eyes (54.2%) developed posterior capsular opacification and were treated with Nd:YAG laser capsulotomy.

CONCLUSION

Clear lens extraction is a safe, effective, and predictable procedure for the treatment of hyperopia from +6.75 to +13.75 D. The SRK II formula proved slightly superior to the SRK-T in intraocular lens calculation when using the "-1.50 D rule."

Iris Claw Phakic Intraocular Lens for High Myopia

BACKGROUND

The implantation of a Worst-Fechner iris claw intraocular lens (IOL) is one of the surgical procedures used for the correction of high myopia. This technique reduces myopia with stable refractive results; however, its potential long-term risks have not been evaluated. We report results in 94 eyes with a minimum follow-up of 3 years.

METHODS

We studied 94 eyes of 62 patients with myopia > or = -7.00 diopters (D) who underwent Worst-Fechner IOL implantation. Lens decentration, permeability of the blood-aqueous barrier by iris angiography, and changes in corneal endothelial density were analyzed.

RESULTS

Mean follow-up time was 48.9 months (range 36 to 72 mo). Three years after surgery, 58 eyes (61%) had an uncorrected visual acuity > or = 20/40, and 77 eyes (82%) gained two or more lines of spectacle-corrected visual acuity with respect to the preoperative value; 75 eyes (79%) were within +/- 1.00 D of emmetropia and 46 eyes (48%) were within +/- 0.50 D of emmetropia. The mean endothelial cell loss was 17.9% at 5 years after surgery, while the percentage of hexagonality and the coefficient of cell variation tended toward preoperative levels. No vision threatening complications were seen.

CONCLUSIONS

The implantation of a Worst-Fechner iris claw phakic IOL reduced high myopia with a stable refractive outcome. Endothelial cell damage was within acceptable limits. The absence of major complications makes this procedure an acceptable method for correcting high myopia.