Long-term results of surgical treatment of high myopia with Worst-Fechner intraocular lenses

A Survey of Intraocular Lens Explantation: A Retrospective Analysis of 23 IOLs Explanted during 2005

Purpose

To evaluate the indications, lens styles, perioperative findings, and results of intraocular lens (IOL) explantation or exchange performed in the authors department in 2005.

Methods

The retrospective analysis comprised 22 patients (23 eyes). Twenty-one eyes had previous phacoemulsification and IOL implantation, one eye secondary aphakic IOL, and one eye phakic IOL implantation. The indications for IOL explantation/exchange and perioperative complications were evaluated. The best-corrected visual acuity (BCVA) before and after surgery was compared.

Results

Time from initial surgery to explantation/exchange varied from 1 to 121 months, median value was 46 months. The IOLs were explanted using local anesthesia and in 21 eyes replaced with new lens. Indications for IOL removal were opacification of the IOL in 12 eyes, malposition of the IOL in 5 eyes, postoperative refractive error in 2 eyes, recurrent toxic anterior segment syndrome in 1 eye, pseudophakic dysphotopsia in 1 eye, endothelial cell loss in phakic anterior chamber IOL in 1 eye, and visual discomfort with intraocular telescopic lens in 1 eye. The mean BCVA (decimal scale) before and after IOL explantation/exchange was 0.562±0.279 and 0.627±0.276, respectively. There was no significant difference in visual acuity before and after IOL exchange (Wilcoxon test).

Conclusions

The most frequent indications for IOL explantation/exchange were opacification of the IOL and IOL malposition. Surgeries were uneventful in most cases. Final visual results have been largely good. Long-term follow-up of patients with various types of IOLs should be maintained.

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.

[Iris-fixated intraocular lenses: reinforced monitoring]

In 1986, the concept of the claw lens was applied to correct myopia in phakic patients. Since then, progress has made iris-fixated phakic intraocular lenses (IOL) relatively safe, predictable, and effective for the correction of myopia, hyperopia, and astigmatism. All these models have undergone a series of design improvements to prevent complications. Despite having excellent refractive results, the principal risk is a potential progressive endothelial cell loss. Many authors have presented encouraging results. Phakic iris-fixated IOL surgery is a potentially reversible procedure, but the surgeon cannot rule out the possibility of complications. Therefore, long-term follow-up is mandatory.

Long-term Follow-up of Endothelial Cell Change after Artisan Phakic Intraocular Lens Implantation

OBJECTIVE

To report endothelial cell densities (ECDs) and their correlation to anterior chamber depth (ACD) after implantation of the Artisan intraocular phakic lens.

DESIGN

Prospective observational case series.

PARTICIPANTS

Three hundred eighteen eyes of 173 myopic patients treated with the Artisan iris-fixated phakic intraocular lens (IOL).

METHODS

Eyes with an ACD ranging between 2.89 and 4.5 mm were implanted with the Artisan phakic IOL. Endothelial cell density measurements were performed preoperatively and at each follow-up examination using a noncontact specular microscope.

MAIN OUTCOME MEASURES

Endothelial cell density (cells per square millimeter).

RESULTS

Follow-up ranged between 1 (82 eyes) and 7 years (13 eyes) (mean, 35.3+/-20.7 [standard deviation] months per eye). After 3 years, there was a significant loss in ECD (P< or =0.03). At 5 years, mean observed endothelial cell loss was 8.3% (5.3% corrected for a natural endothelial cell loss of 0.6% a year). Endothelial cell density loss remained progressive throughout our follow-up period. After 3 years, a significant negative correlation between ACD and endothelial cell loss was revealed (P< or =0.03). Patient age, gender, refractive error, incision size, and side of the eye were not correlated to ECD loss. All corneas remained clear throughout the study.

CONCLUSION

After 3 years, a significant ECD loss was revealed. This ECD loss was significantly negatively correlated to the ACD. We therefore suggest that eyes just meeting the minimum ECD requirement have greater ACDs to compensate for possible greater endothelial cell loss and that patients with shallow anterior chambers have higher ECDs. Artisan phakic lens implantation in young eyes narrowly meeting the minimum criteria of endothelial cell density (2,000 cells/mm(2)) and ACD (2.6 mm) should perhaps be reevaluated, due to longer exposure to higher rates of endothelial cell loss.

Long-term endothelial changes in phakic eyes after Artisan intraocular lens implantation to correct myopia: five-year study

PURPOSE

To evaluate long-term endothelial cell changes in eyes that had implantation of an iris-fixated phakic Artisan intraocular lens (IOL) for moderate to high myopia.

SETTING

Casa di Cura Villa Igea, Ancona, Italy.

METHODS

Forty-nine eyes of 30 patients having implantation of Artisan IOL for moderate to high myopia were prospectively examined. Preoperative specular microscopy and serial postoperative specular microscopy (Noncon Robo SP 8000, Konan Medical) were performed to evaluate endothelial cell changes over 5 years. Endothelial cell images were collected in the central region of the cornea before surgery and 4, 12, 24, 36, 48, and 60 months after surgery. The endothelial cell density (ECD), coefficient of variation, and percentage of hexagonal cells were determined.

RESULTS

Preoperatively, the mean ECD was 2616 cells/mm(2) +/- 347 (SD), the mean coefficient of variation was 39.6% +/- 4.7%, and the mean percentage of hexagonal cells was 49.2% +/- 6.7%. The mean endothelial cell loss from preoperatively was 2.3% at 4 months, 3.5% at 12 months, 4.7% at 24 months, 6.7% at 3 years, 8.3% at 4 years, and 9.0% at 5 years. Five years after surgery, the mean coefficient of variation was 35.9% +/- 6.9% (P = .1946) and the percentage of hexagonal cells was significantly higher (mean 54.7% +/- 10.3%) (P = .087).

CONCLUSIONS

Continuous endothelial cell loss was observed after surgery during a 5-year follow-up, especially during the first 2 years. A decrease in the coefficient of variation and an increase in the percentage of hexagonal cells were observed over time, reflecting the increasing stability and remodeling of the corneal endothelial cells 5 years postoperatively.

Recurrent iritis after implantation of an iris-fixated phakic intraocular lens for the correction of myopia

The iris-claw intraocular lens (IOL) was recently approved by the U.S. Food and Drug Administration for the correction of refractive disorders. Previous reports are not uniform regarding its potential to induce inflammatory reaction. We report the case of a young healthy patient who experienced persistent and intolerable iritis after implantation of an iris-claw IOL. The iritis was resolved only after explantation of the IOL.

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.

Rate of Cataract Formation in 343 Highly Myopic Eyes After Implantation of Three Types of Phakic Intraocular Lenses

PURPOSE

To assess the feasibility of using phakic intraocular lenses (PIOL) to treat high myopia, and evaluate the incidence of cataract, comparing three different lens types.

METHODS

From 1989 to 2002, we implanted three different phakic intraocular lenses (PIOL) in 343 eyes of 232 patients; 231 eyes recieved an Ophtec (Worst-Fechner model, iris-claw), 89 an Adatomed (silicone posterior chamber), and 23 a Staar (posterior chamber, models V2, V3, V4). Average follow-up was 96.2 months for the Ophtec group, 31.5 months for the Adatomed group, and 19.3 months for Staar group. Eyes that subsequently developed cataract were studied for clinical evolution and had PIOL explantation and cataract extraction.

RESULTS

Nuclear cataract developed in 7 of 231 eyes (3.04 %) with an Ophtec lens. Anterior subcapsular cataract developed with the two types of posterior PIOLs (Adatomed group: 38/89 eyes, 42.69%; Staar group: 3/23 eyes, 13.04%). Anterior subcapsular cataract in the Adatomed group developed more rapidly compared to the Staar group. We explanted 7 lenses in the Ophtec group, 16 lenses in the Adatomed group, and 2 lenses in the Staar group (models V2 and V3 only). Patient age older than 40 years at implantation of PIOLs and axial length greater than 30 mm were factors significantly related to nuclear cataract formation and the Ophtec lens. However, these two factors had a weaker correlation with the posterior phakic lenses (Adatomed, Staar) for high myopia than with the Ophtec lens. Postoperative best spectacle-corrected visual acuity remained stable after explantation, phacoemulsification, and posterior chamber lens implantation.

CONCLUSIONS

Delayed cataract development and cataract type (nuclear) in patients with an Ophtec lens and the variables of patient age (>40 yr) and axial length (>30 mm) may considered prognostic factors. Other factors such as lens design, material, and placement probably influenced cataract formation in patients with the Adatomed and Staar PIOLs. The lens styles used in this study are no longer manufactured.

Ultrasound biomicroscopy and Scheimpflug photography of angle-supported phakic intraocular lens for high myopia

PURPOSE

To evaluate the equivalence of Scheimpflug photography (SP) and ultrasound biomicroscopy (UBM) in determining corneal epithelium-intraocular lens (IOL) and border IOL-iris distances.

SETTING

Universität Erlangen-Nuremberg, Erlangen, Germany.

METHODS

In 26 eyes of 17 patients who had a NuVita MA20 angle-supported anterior chamber intraocular lens (Chiron-Domilens), SP and UBM were used to evaluate the distance between the endothelium and the anterior IOL face in central and peripheral regions (12 o'clock and 6 o'clock positions) and between the border of the anterior IOL face and the iris. The Wilcoxon test was used for statistical analysis.

RESULTS

The mean central endothelium-anterior IOL face distance was 2.01 mm and 2.00 mm by SP and UBM, respectively. The mean peripheral endothelium-anterior IOL border distance was 1.28 mm and 1.58 mm, respectively, and the mean peripheral anterior IOL face-iris distance, 0.89 mm and 0.75 mm, respectively.

CONCLUSIONS

The difference between the 2 methods in the central endothelium-anterior IOL face distance was not significant (methods were equivalent), but the difference in the peripheral endothelium-anterior IOL face distance was. This may be the result of difficulty in obtaining the exact transition point between the IOL and the haptics by SP examination. The difference between the 2 methods in the IOL border-iris distance was also significant because of the irregularity of the iris surface; therefore, measurements were performed at different sites along this structure. The significant differences in the peripheral endothelium-IOL and IOL border-iris distances indicate that although both methods are useful, they are not equivalent.

U.S. Food and Drug Administration clinical trial of the Implantable Contact Lens for moderate to high myopia

PURPOSE

To assess the safety and efficacy of the Implantable Contact Lens (ICL) to treat moderate to high myopia.

DESIGN

Prospective nonrandomized clinical trial.

PARTICIPANTS

Five hundred twenty-three eyes of 291 patients with between 3 and 20.0 diopters (D) of myopia participating in the U. S. Food and Drug Administration clinical trial of the ICL for myopia.

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, lens opacity analysis (Lens Opacity Classification System III), subjective satisfaction, and symptoms.

RESULTS

Twelve months postoperatively, 60.1% of patients had a visual acuity of 20/20 or better, and 92.5% had an uncorrected visual acuity of 20/40 or better. Patients averaged a 10.31-line improvement in UCVA, 61.6% of patients were within 0.5 D, and 84.7% were within 1.0 D of predicted refraction. Only one case (0.2%) lost > 2 lines of BSCVA. Gains of 2 or more lines of BSCVA occurred in 55 cases (11.8%) at 6 months and 41 cases (9.6%) at 1 year after ICL surgery. Early and largely asymptomatic, presumably surgically induced anterior subcapsular (AS) opacities were seen in 11 cases (2.1%); an additional early AS opacity (0.2%) was seen because of inadvertent anterior chamber irrigation of preservative-containing solution at surgery. Two (0.4%) late (> or = 1 year postoperatively) AS opacities were observed. Two (0.4%) ICL removals with cataract extraction and intraocular lens implantation have been performed. Patient satisfaction (very/extremely satisfied) was reported by 92.4% of subjects on the subjective questionnaire; only four patients (1.0%) reported dissatisfaction. Slightly more patients reported an improvement at 1 year over baseline values for the following subjective symptoms: quality of vision, glare, double vision, and night driving difficulties. Only a 3% difference between pre-ICL and post-ICL surgery was reported for haloes.

CONCLUSIONS

The results support the safety, efficacy, and predictability of ICL implantation to treat moderate to high myopia.

Phakic posterior chamber intraocular lens pupillary block

A 49-year-old woman developed bilateral pupillary block after implantation of a phakic posterior chamber intraocular lens despite patent-appearing but nonfunctional peripheral iridotomies. This case serves as a basis to identify clinical signs that distinguish this diagnosis from other causes of elevated intraocular pressure and types of pupillary block.

Anterior chamber intraocular lens for high myopia: five year results

PURPOSE

To evaluate the effectiveness of the surgical correction of high myopia 5 years after anterior chamber intraocular lens (IOL) implantation and to analyze the lens position and related complications.

SETTING

Federal University of São Paulo-Escola Paulista de Medicina, São Paulo, Brazil.

METHODS

This prospective study comprised 26 eyes that were implanted with an anterior chamber IOL (model ZB5M) and had a minimum follow-up of 5 years. Before and after surgery, manifest and cycloplegic refractions were done; slitlamp examination was performed; anterior chamber depth was measured; and keratometry, ophthalmoscopy, and central corneal endothelial cell count were performed. At the last follow-up, computerized biomicroscopy of the anterior segment was also done.

RESULTS

The spherical equivalent decreased from -16.5 diopters (D) +/- 4.1 (SD) preoperatively to -0.9 +/- 0.9 D postoperatively. At the last examination, 57.7% of eyes had a spherical equivalent refraction within +/-1.0 D of emmetropia. Of eyes with a preoperative best spectacle-corrected visual acuity of 20/40 or better, 73.3% had an uncorrected visual acuity of 20/40 or better postoperatively. The mean tilt caused by the IOL was 4.4 +/- 2.7 degrees (range 0.5 to 12.2 degrees) and the mean IOL decentration, 0.3 +/- 0.2 mm (range 0.02 to 0.8 mm). The mean decrease in the endothelial cell count was 1.5%, with a mean cell density of 2808 +/- 305 cells/mm2 preoperatively and 2765 +/- 242 cells/mm2 postoperatively. Pupillary ovalization was observed in 12 eyes (46.1%).

CONCLUSIONS

The anterior chamber IOL safely and effectively corrected high myopia.

Adjustable refractive surgery: 6-mm Artisan lens plus laser in situ keratomileusis for the correction of high myopia

PURPOSE

To evaluate efficacy, predictability, stability and safety of adjustable refractive surgery (ARS) by combining a phakic intraocular lens (IOL) (Artisan lens 6-mm optical zone [OZ]) and laser in situ keratomileusis (LASIK) (6.5 mm OZ) for the correction of myopia greater than -15.00 diopters (D).

DESIGN

Noncomparative interventional case series.

PARTICIPANTS

Twenty-six eyes of 18 patients with a preoperative spherical equivalent between -16.00 and -23.00 D.

METHODS

First surgery: An 8.5/9.5-mm flap was created and a 6-mm optic iris claw phakic IOL of -15.00 D was inserted in the anterior chamber through a posterior corneal incision. The second surgery was performed once refraction and topography were stable, between 3 and 5 months later. Second surgery: LASIK enhancement (6.5-9.2 OZ); the flap was relifted, and the residual refractive error was corrected.

MAIN OUTCOME MEASURES

The main parameters in this study were uncorrected visual acuity, best-corrected visual acuity (BCVA), refraction, contrast sensitivity, endothelial cell count (ECC), and subjective response.

RESULTS

Twenty-eight months after both surgeries, 80.70% of the eyes were within 0.50 D of emmetropia and 100% within 1.0 D. Twenty-six percent of the eyes gained 3 or more lines from their preoperative BCVA, and 42% gained 2 or more lines. There was no visual loss in any eye from 6 weeks to 24 months after LASIK enhancement (second surgery) and refraction, and visual acuities remained stable. Two subjects (11%) had some subjective disturbances at night. There was a 0.61% mean loss of ECC during the first 12 months and a 0.60% loss during the next 16 months. No serious complications were observed.

CONCLUSIONS

ARS with the combination of a 6-mm optic, 15 D Artisan lens, and LASIK appears to be a safe and highly predictable method for the correction of myopia greater than -15.00 D. It is the best approach with the technology currently available.

Long-term Results of Correction of High Myopia With an Iris Claw Phakic Intraocular Lens

PURPOSE

Anterior chamber phakic intraocular lenses (PIOLs) are one of the modalities used to correct high myopia. We report the long-term results of our prospective study on the Artisan 5-mm optic myopia lens.

METHODS

We studied 67 eyes of 38 consecutive patients with preoperative myopia ranging from -5.38 to -28.00 D. All patients were operated by one surgeon. Mean follow-up was 35 months (24 months in 67 eyes and 36 months in 61 eyes).

RESULTS

In 45 eyes (67.2%), postoperative residual refraction was within +/- 1.00 D of emmetropia. The mean refraction was stable statistically during the entire follow-up period. Mean best spectacle-corrected visual acuity improved from 20/40 to 20/32. Mean endothelial cell loss at 6 months was 5.5% (range, -52.4% to +9.3%), at 12 months, 7.21% (range, -53.2% to +20.1%), at 24 months, 9.1% (range -43.6% to +13.6%), and at 36 months, 10.9% (range, -43.0O% to +11.4%). The majority of eyes had an increase in best spectacle-corrected visual acuity; 5 eyes lost best spectacle-corrected visual acuity. We encountered no major complications.

CONCLUSION

Implanting the Artisan 5-mm optic myopia lens in high myopic eyes resulted in a stable and accurate refractive outcome. The apparent progressive corneal endothelial cell loss remains a matter of concern.

Posterior chamber silicone intraocular lens for the correction of myopia: an experimental study in rabbits

PURPOSE

To establish whether ocular lesions arise after implantation of posterior chamber silicone intraocular lenses (IOL) for the correction of high myopia.

METHODS

Twenty-three posterior chamber silicone IOL were implanted in 23 eyes of the same number of pigmented rabbits. After different follow-up time (from one week to one year) the eyes were enucleated and processed for histopathological study after determining the protein concentration in the aqueous humor. The IOL were removed for staining and examination, and adhered cells were counted. Ten eyes analogous to those operated upon were used as controls.

RESULTS

Intense inflammation was observed in the early postoperative period in all cases. Protein concentration in the aqueous humor was initially high and decreased over time, though without reaching normal values at one year. Mono- and multinucleated cells were seen adhering to the IOL, though they decreased in number over time and were practically absent after one year. Friction between the posterior surface of the iris and the IOL had no clinical repercussions. The only pigment accumulations were in the iris and in the peritrabecular zone. There were no significant differences in the accumulation of granules in relation to IOL diameter or power. Excluding three cataracts morphologically similar to traumatic cataracts, five lens opacifications were observed: two were anterior subcapsular cataracts, and the other three were only precapsular deposits. The IOL had no synechiae to the ocular tissues.

CONCLUSIONS

Opacification of the lens is the main concern with implanted posterior chamber silicone IOL. Larger series of eyes must be analysed to establish the true incidence and reversibility of these opacities.

Pathological examination of an explanted phakic posterior chamber intraocular lens

PURPOSE

To report the clinicopathological correlation of an explanted phakic posterior chamber intraocular lens (PPC IOL) and to study the conformation of this lens implanted into human eyes obtained postmortem.

SETTING

Center for Research on Ocular Therapeutics and Biodevices, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS

Three silicone PPC IOLs were explanted. One lens, explanted from a 38-year-old woman with complicated cataract, was submitted for pathological analysis. In addition to gross and scanning electron microscopy (SEM), the lens was studied after experimental implantation in human eyes obtained postmortem using frontal, posterior, and side-view techniques.

RESULTS

Although gross and SEM showed that the IOL was well polished, examination of the lens in human cadaver eyes showed it was oversized and poorly fixated. It was relatively bulky in its anterior-posterior dimension and revealed evidence of significant contact with the iris and crystalline lens.

CONCLUSIONS

This study illustrates many pitfalls to be avoided in the design of a plate PPC IOL. The lens in this report was too large, and instead of ciliary sulcus fixation, it showed poor fixation through the zonules onto the posterior face of the pars plicata. Present and future PPC IOLs should be submitted for similar preclinical studies to clarify the type and site of fixation.

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.

Iris-claw lens in phakic eyes to correct hyperopia: preliminary study

PURPOSE

To evaluate the results of implanting convex, iris-fixated, anterior chamber intraocular lenses (IOLs) in phakic eyes to correct high hyperopia.

SETTING

Robert Koch Hospital, Hannover-Gehrden, Germany (Center A), and Dr. Daljit Singh Eye Hospital, Amritsar, India (Center B).

METHOD

Two eyes at Center A and 67 at Center B had implantation of an anterior chamber, convex, iris-fixated IOL. Follow-up of the 2 eyes at Center A was 91 months. Mean follow-up at Center B was 78 months +/- 24 (SD) (range 12 to 120 months).

RESULTS

At Center B, all eyes except two in one patient had clear corneas and no iritis or glaucoma at the last follow-up. The patient with complications (glaucoma and corneal degeneration in both eyes) did not return for follow-up until more than 4 years postoperatively and thus did not have adequate postoperative care.

CONCLUSION

Implantation of a convex iris-claw lens into the anterior chamber of phakic eyes to correct high hyperopia was successful from a refractive aspect. The clinical risks appear tolerable. However, life-long observation by endothelial microscopy is mandatory.

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.

Keratomileusis in situ for high myopia

PURPOSE

To examine the safety and efficacy of myopic keratomileusis in situ (automated lamellar keratoplasty) using an automated microkeratome.

SETTING

Jules Stein Eye Institute and the Department of Ophthalmology, UCLA School of Medicine, Los Angeles, California.

METHODS

A retrospective study was done on 135 consecutive eyes of 91 patients who had keratomileusis in situ for myopia by one surgeon between October 4, 1993, and February 23, 1995. Mean preoperative myopia was 8.30 +/- 2.50 diopters (D) (range 4.50 to 20.50). Follow-up ranged from 1 (108 eyes) to 6 months (52 eyes). No eye had enhancement surgery before 3 months; eyes were dropped from the study at the time of enhancement.

RESULTS

Three months after myopic keratomileusis in situ, the mean difference between attempted and achieved correction was an undercorrection of 0.90 +/- 1.50 D; 32 of 83 eyes were within 1.00 D of attempted correction. Forty eyes were undercorrected by more than 1.00 D, and 11 were overcorrected by more than 1.00 D. Uncorrected visual acuity improved to 20/40 or better in 42 of 83 eyes at 3 months. Best spectacle-corrected visual acuity (BSCVA) declined by two or more lines in 8 of 83 eyes at 3 months and 1 of 52 eyes at 6 months. In eyes with 6 months of follow-up, a mean myopic shift of 0.40 D occurred between 3 and 6 months. Two eyes had clinically significant ingrowth into the interface. The variability in outcome (standard deviation in achieved less attempted correction) at 3 months was 1.70 D in the first 45 cases, 1.20 D in the second 45 cases, and 1.10 D in the last 45 cases.

CONCLUSION

Myopic keratomileusis in situ is relatively effective and safe for the correction of high myopia; however, a mild loss of BSCVA is not uncommon in the early postoperative period. Surgeon experience may be important for refractive accuracy.

Iris-fixated Worst claw versus sulcus-fixated posterior chamber lenses in the absence of capsular support

PURPOSE

To evaluate visual outcomes and complications of iris-fixated intraocular lenses (IOLs) (lobster-claw) and sutured sulcus-fixated posterior chamber (PC) IOLs in primary and secondary implantation.

SETTING

Eye Department, University Hospital "La Fe", Valencia, Spain.

METHODS

This retrospective study reviewed 47 patients who had primary implantation of an iris-fixated (n = 34) or sulcus-fixated (n = 13) IOL and 54 patients who had secondary implantation of an iris-fixated (n = 41) or sulcus-fixated (n = 13) IOL.

RESULTS

Visual acuity in the primary implantation group was similar with both lens types. Overall, 54.0% had a postoperative acuity of 20/40 or better. In eyes without pre-existing pathology, 60.0% with an iris-fixated IOL and 54.6% with a sutured PC IOL had this level of postoperative acuity (P = .768). In the secondary implantation group, the percentage of patients with a postoperative visual acuity of 20/40 or better was significantly higher in iris-fixated IOL eyes (78.0%) than in sulcus-fixated PC IOL eyes (46.2%) (P < .05). In eyes without pre-existing pathology, the difference was maintained. No intraoperative complications directly associated with iris-fixated lens implantation occurred. The incidence of postoperative complications common to either IOL type in primary and secondary implantation did not differ significantly. The incidence of retinal complications was higher in eyes that had primary implantation of either lens type, although the differences between both lenses in either primary or secondary implantation were not significant.

CONCLUSION

The good visual outcomes and low incidence of intraoperative and postoperative complications in eyes with iris-fixated IOLs indicate that these lenses should be considered an alternative to sutured PC IOLs in eyes in which capsular support is inadequate or absent.