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

Late-onset decentration of iris-fixated phakic intraocular lenses: a case series

PURPOSE

To investigate late-onset downward decentration of iris-fixated phakic intraocular lenses (pIOL) resulting from progressive shifting of the haptics through the iris and its influence on the position of the pIOL and the amount of enclavated iris tissue.

DESIGN

Institutional, prospective, observational case series.

METHODS

Six patients (9 eyes) from among 368 eyes had 1 shifted haptic during long-term follow-up. Anterior segment optical coherence tomography (AS-OCT) was used to measure the distance between the edges of the pIOL and the corneal endothelium. Slit-lamp photography imaged the pIOL after implantation and after decentration. The images were analyzed to determine decentration and amount of iris tissue at the enclavation sites.

RESULTS

Shifting of the haptics occurred in 2.4% and was discovered at a mean follow-up of 4.8 years (range, 3 to 7 years). Mean downward decentration was 0.28 +/- 0.15 mm. Mean edge-distances on the nasal, temporal, superior, and inferior side were 1.71 +/- 0.30 mm, 1.86 +/- 0.31 mm, 1.86 +/- 0.31 mm, and 1.58 +/- 0.34 mm, respectively. Mean enclavated iris tissue on the nasal and temporal side was smaller after decentration when compared with that directly after surgery (P = .033 and P = .017, respectively). Shifting of the haptics did not result in a decreased uncorrected and best-corrected visual acuity.

CONCLUSIONS

Late-onset downward decentration resulting from progressive shifting of the haptics occurred in 2.4% and was associated with a decrease in enclavated iris tissue. AS-OCT showed a mean distance between the edge of the pIOL and the endothelium greater than the advised safety distance of 1.5 mm.

Case of late-onset corneal decompensation after iris-fixated phakic intraocular lens implantation

A 48-year-old myopic patient with bilateral anterior chamber depth of 3.1 mm and endothelial cell density (ECD) of 2525 cells/mm(2) and 2638 cells/mm(2) preoperatively had bilateral implantation of an Artisan iris-fixated phakic intraocular lens (pIOL). Five years postoperatively, unilateral corneal stromal edema was seen in a circumscribed area overlying the temporal ridge of the pIOL in the right eye; the ECD was 1631 cells/mm(2) and the pachymetry, 586 microm. Explantation of the pIOL was refused by the patient. Seven years postoperatively, the ECD was 413 cells/mm(2) in the right eye and corneal decompensation occurred. The progressive unilateral endothelial loss was explained by excessive rubbing of the eyes because of chronic itching and an anterior shift of the pIOL over the 7 years as demonstrated by anterior optical coherence tomography.

Influence of anterior chamber morphometrics on endothelial cell changes after phakic intraocular lens implantation

PURPOSE

To analyze the position of iris-fixated phakic intraocular lenses (pIOLs) using anterior segment optical coherence tomography (AS-OCT) and evaluate the effect of anterior chamber morphometrics on endothelial cell changes.

SETTING

Department of Ophthalmology, Academic Hospital Maastricht, The Netherlands.

METHODS

In this cross-sectional study, AS-OCT was used to measure the distances from the center and the edges of the pIOL to the corneal endothelium in 242 eyes with various models of myopic pIOLs. Endothelial cell measurements were performed preoperatively and at each follow-up examination.

RESULTS

The mean follow-up was 34.1 months+/-24.7 (SD) (range 3 months to 7 years). The mean distance between the edge of the pIOL and the endothelium was 1.37+/-0.22 mm. Although this distance was smaller than the safety value of 1.50 mm in 68.6% of the eyes, no eye developed corneal decompensation. There was a significant endothelial cell density (ECD) loss of 1.28%+/-8.46%, 3.25%+/-8.24%, and 5.02%+/-10.40% at 2 years, 5 years, and 7 years, respectively. Linear mixed-model analysis predicted a yearly ECD loss of 0.98% for a mean edge distance of 1.37 mm, 0.15% for an edge distance of 1.59 mm (mean plus 1 SD), and 1.80% for an edge distance of 1.15 mm (mean minus 1 SD).

CONCLUSIONS

A shorter distance between the edge of the pIOL and the endothelium was significantly associated with higher ECD loss. For safety reasons, the postoperative examination should include long-term evaluation of the anterior chamber morphometrics in addition to ECD counts.

Long-term endothelial cell loss after traumatic dislocation and repositioning of Artisan phakic IOL

PURPOSE

To evaluate long-term endothelial cell loss after traumatic dislocation and repositioning of an Artisan phakic intraocular lens (PIOL).

METHODS

Traumatic PIOL dislocation occurred in the patient's left eye 4 months after uneventful implantation for unilateral congenital myopia. Using the Konan semi-automated analysis method, endothelial cell density was measured preoperatively, before Artisan repositioning, and 1, 2, and 4 years after primary implantation.

RESULTS

Endothelial cell density was 2770 cells/mm2 preoperatively and 2634 cells/mm2 before Artisan repositioning. After successful repositioning, endothelial cell density progressively decreased--1, 2, and 4 years from primary implantation, endothelial cell density was 2582, 2524, and 2538 cells/mm2, respectively, corresponding to losses of 6.8%, 8.9%, and 8.4%, respectively.

CONCLUSIONS

Progressive and long-term endothelial loss after traumatic dislocation and repositioning of the Artisan PIOL may be comparable to that reported after uneventful implantation.

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.

Behaviour of the phakic iris-claw intraocular lens (Artisan /Verisyse) during accommodation: an optical coherence biometry study

PURPOSE

To evaluate variations in the position of the phakic iris claw lens (Artisan, Verisyse) and the natural crystalline lens during the accommodation process.

METHODS

We measured changes in position of the iris claw lens and the crystalline lens during the accommodation using optical coherence biometry (AC Master/Carl Zeiss Meditec, Germany) in 17 patients (28 eyes) with a phakic iris claw lens implanted for high myopia and/or myopic astigmatism. Accommodative effort was obtained using an internal optical target within the measuring device.

RESULTS

There was a forward shift of the phakic iris claw lens with a mean of 70 microm (8-178 microm) of the optical path length (OPL). At the same time the anterior pole of the natural lens showed a forward mean movement of 85 microm (4- 260 microm).

CONCLUSIONS

An anterior displacement of the iris-claw phakic lens was shown in a series of eyes during the accommodation process. As this displacement goes along with the forward displacement of the anterior pole of the crystalline lens, the preoperative measurement of the latter might provide some additional information about the position of the iris claw lens in the accommodative state after implantation.

Reliability of a video-based noncontact specular microscope for assessing the corneal endothelium

PURPOSE

To assess the within- and between-examiner reliability of corneal endothelial cell density (ECD) measurements with 2 noncontact specular microscopes: a video-based system (SeaEagle) and a photographic system (Noncon Robo).

METHODS

In 57 eyes of 57 subjects, 47 healthy subjects and 10 patients with corneal disease, ECD was measured in the center and at 4 paracentral areas with the video-based system (SeaEagle) and in the center with a photographic system (Noncon Robo). For the between-examiner reliability, a second examiner measured the central ECD with the SeaEagle device in 12 healthy subjects. The video-based system was also used to evaluate the agreement between the automated and the manually corrected (semiautomated) modes of repeated measurements.

RESULTS

For central ECD in all eyes, the test-retest reliability assessed by the intraclass correlation coefficient was 0.77, 0.99, and 0.91 for the automated SeaEagle, semiautomated SeaEagle, and Noncon Robo, respectively. Correlation was poor to good between the 3 measurement methods (range, 0.61-0.84). For between-examiner reliability, the upper (lower) limits of agreement were 200 (-384) and 149 (-92) cell/mm for the automated and semiautomated SeaEagle, respectively.

CONCLUSIONS

The best reliability of repeated measurements was found for the semiautomated SeaEagle. However, the semiautomated method showed significantly higher ECD values than the Noncon Robo, and this difference was highly dependent on ECD. Thus, we suggest that these methods should not be used interchangeably. The fully automated mode may need a further refinement of the cell detection algorithm.

[Toric phakic intraocular lenses]

After more than 3 years of follow-up, the satisfactory results achieved with the toric iris-fixated phakic intraocular lens (IOL) mean we can regard implantation of this lens as a procedure with the potential to provide safe, predictable, effective and stable correction of astigmatic errors, providing patients are carefully selected and receive adequate preparation for surgery. The iris-fixated toric phakic IOL (Verisyse, Advanced Medical Optics; Artisan, Ophtec) is a PMMA lens with a total diameter of 8.5 mm and an optic diameter of 5 mm. It has a spherical anterior and a toric posterior surface. Its refractive power ranges from -2 dpt to -21 dpt for myopia and from +2 dpt to +12.5 dpt for the correction of hyperopia. Cylindrical correction is available from 2 dpt to 7.5 dpt. The Visian toric implantable Collamer lens (Staar) differs in that it is foldable and can be inserted through a very small incision of about 2.8 mm. It is placed in front of the natural lens in the ciliary sulcus. The aim of implanting these phakic IOLs is to correct the entire refractive error, meaning both the spherical and the astigmatic error, in a single step. Different lens models are available, and the selection depends on the direction of the cylinder axis and the anatomical situation, among other things.

Posterior iris fixation of the iris-claw intraocular lens implantation through a scleral tunnel incision

PURPOSE

To evaluate the technique, efficacy, and safety of posterior iris fixation of iris-claw intraocular lens (IOLs) implantation through a scleral tunnel incision for aphakia correction.

DESIGN

Noncomparative, interventional case series.

METHODS

A secondary posterior iris fixation of the Artisan iris-claw IOL (Ophthec BV, Groningen, The Netherlands) was implanted for aphakia correction in the authors' clinical practice. Uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), astigmatism, manifest refraction, lens position, pigment dispersion, and intraocular pressure (IOP) were evaluated in 32 consecutive eyes of 32 patients.

RESULTS

BSCVA was 20/40 or better in 28 eyes (87.50%) during the mean follow-up time (nine months). Mean postoperative spherical equivalent was -0.70 diopters (D; standard deviation [SD], 0.47 D) at six months after surgery. Mean prediction error was -0.13 D (SD, 0.28 D), and mean absolute prediction error was 0.26 D (SD, 0.15 D). Preoperative mean astigmatism was -1.08 D (SD, 0.55 D; range, 0.0 to -2.0 D). At six months after surgery, mean astigmatism was -2.1 D (SD, 0.81 D; range, -0.75 to -3.75 D). There was no significant postoperative IOP increase. Lens position, evaluated by Oculus Pentacam (Pentacam 70700: Oculus, Wetzlar, Germany) and ultrasound biomicroscopy [UBM] (Ophthalmic Technologies Inc, Toronto, Ontario, Canada), was parallel to the iris plane.

CONCLUSIONS

Posterior iris fixation of the iris-claw IOL implantation through a scleral tunnel incision is a safe procedure and an effective option for aphakic eyes without capsule support.

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

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

Evaluation of Verisyse and Artiflex phakic intraocular lenses during accommodation using Visante optical coherence tomography

PURPOSE

To perform a dynamic study of the relationship between Verisyse (AMO) and Artiflex (Ophtec B.V.) phakic intraocular lenses (pIOLs) and anterior chamber structures during accommodation using optical coherence tomography (OCT) (Visante, Carl Zeiss Meditec, Inc.)

SETTING

Institutional practice.

METHODS

Eleven myopic patients were randomly selected to have implantation of a Verisyse pIOL in 1 eye and an Artiflex pIOL in the other. Using a 2-dimensional image, dynamic measurements of the relationship between the anterior surface of the pIOL and the corneal endothelium, the posterior surface of the pIOL and the anterior surface of the crystalline lens, and the pupil diameter were performed using Visante OCT. Physiological accommodation was stimulated by adding lenses in 1.00 diopter (D) steps from +1.00 to -7.00 D.

RESULTS

Both groups had a significant decrease in pupil diameter (P<.0001, generalized linear model [GLM]) and in the distance between the anterior surface of the pIOL and the corneal endothelium (P<.0001, GLM) with accommodation. There were no statistically significant changes in the distance between the posterior surface of either pIOL and the anterior surface of the crystalline lens (P = .2845, GLM). There were no statistically significant differences between the 2 pIOLs in any measurement (P>.05, GLM).

CONCLUSIONS

The results fit with Helmholtz' theory of accommodation as forward movement of the diaphragm iris-crystalline lens was seen. There was a decrease in the distance between the pIOL and corneal endothelium and in the pupil diameter, whereas the distance between both pIOLs and the crystalline lens remained constant throughout the accommodation examination. This suggests that the risk for cataract from intermittent contact between the crystalline lens and IOL from accommodative effort is unlikely.

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.

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.

Calculating the power of toric phakic intraocular lenses

BACKGROUND AND PURPOSE

A toric phakic intraocular lens (IOL) implanted in the anterior or posterior chamber of the eye has the potential to correct high or excessive ametropia and astigmatism with high predictability of the postoperative refraction and preservation of phakic accommodation. The calculation of spherical phakic lenses has been described previously, but a formalism for estimating the power of toric phakic lenses has not yet been published. The purpose of this study is to describe a mathematical strategy for calculating toric phakic IOLs.

METHODS

The method presented in this paper is based on vergence transformation in the paraxial Gaussian space. Parameters used for the calculations are the spherocylindrical spectacle refraction before implantation, corneal power (sphere and astigmatism) and (spherocylindrical) target refraction, together with the vertex distance and the predicted position of the phakic IOL. The lens power is determined as the difference in vergences between the spectacle-corrected eye and the uncorrected eye at the reference plane of the predicted lens position. The axes of the preoperative refraction, the target refraction and the corneal astigmatism are at random (not necessarily aligned).

RESULTS

The method was applied to two clinical examples. In example 1 we calculate the power of a phakic lens for the simple case, when the target refraction is plano and the axis of the preoperative refraction is aligned to the axis of the corneal astigmatism. In example 2, the cylindrical axis of the preoperative refraction is not aligned to the corneal astigmatism and the target refraction is spherocylindrical (and the axis of the target refraction is not aligned to the preoperative refractive cylinder or the corneal astigmatism). The calculations for both examples are described step-by-step and illustrated in a table.

CONCLUSIONS

The calculation scheme can be generalized to an unlimited number of crossed cylinders in the optical pathway. Based on paraxial raytracing, the spherical and cylindrical power as well as the orientation of the cylinder are determined from the preoperative refraction (including vertex distance), the corneal power, the intended target refraction (including vertex distance) and the predicted position of the phakic lens implant provided by the lens manufacturer. This calculation scheme can be easily implemented in a simple computer program (i.e. in Microsoft excel or matlab).

Long-term Study of Artisan Phakic Intraocular Lens Implantation for the Correction of Moderate to High Myopia

PURPOSE

To determine the long-term performance of the Artisan phakic intraocular lens (PIOL) for the correction of myopia.

DESIGN

Long-term (10 years) retrospective follow-up study.

PARTICIPANTS

Eighty-nine eyes of 49 patients who underwent Artisan PIOL implantation for the correction of myopia.

METHODS

Comparisons were made between preoperative clinical data and the clinical data at 1, 6, and 10 years after surgery.

MAIN OUTCOME MEASURES

Refractive stability, refractive predictability, safety, efficacy, best-corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), intraocular pressure, intraoperative problems, corneal endothelial cell density, corneal endothelial cell loss, and glare levels were evaluated.

RESULTS

The mean spherical equivalent (SE) after 10 years was -0.70+/-1.00 diopters (D; range, -4.00 to 2.00 D), with no significant change in mean SE between 1, 6, and 10 years. At 10 years, 68.8% of all eyes were within 1.0 D of the intended correction. At 10 years, 31.2% (n = 24) gained 1 or more Snellen lines of BCVA and 2.6% (n = 2) lost more than 2 Snellen lines of BCVA; 93.3% reached a BCVA of 20/40 or better, and 82.0% reached a UCVA of 20/40 or better. The mean intraocular pressure remained stable and was 15.5+/-3.5 mmHg (range, 7-25 mmHg) at 10 years. The mean endothelial cell loss was -8.86+/-16.01% (range, -51.69% to 34.43%) at 10 years.

CONCLUSIONS

Long-term results demonstrate that the implantation of an Artisan PIOL for the correction of moderate to high myopia is a stable, predictable, and safe method when strict inclusion criteria for surgery are applied. There was no significant loss of corneal endothelial cells and no reports of long-term glare.

Magnification and accommodation with phakic intraocular lenses

BACKGROUND AND PURPOSE

The calculation of phakic lenses (PL) was described by van der Heijde et al. [Klin. Monatsbl. Augenheilkd (1988) Vol. 193, pp. 99-102], but a formalism for estimating relative magnification compared with spectacle correction and accommodation effects are not yet published. The purpose of this study was to describe a mathematical strategy for calculating PL and relative magnification as a function of object vergence (phakic accommodation).

METHODS

Parameters used for the calculations are the spectacle refraction before and after (target refraction) surgery, the vertex distance, corneal refraction, and the predicted position of the phakic intraocular lens. The lens power is determined as the difference in vergences between the spectacle-corrected eye and the uncorrected eye at the reference plane of the predicted lens position. If we simplify the crystalline lens to a single refracting surface located at the principal plane of the crystalline lens, the vergence of the eye with spectacle correction and with PL is determined as a function of object distance [object vergence 0 D (infinity) to 10 D (object at a distance of 10 cm)] to evaluate accommodation effects of the crystalline lens.

RESULTS

The method was applied to two clinical examples. In example 1 we calculated the power of a PL for correction of a 10-D myopia and determined the relative magnification and the vergence at the principal plane of the crystalline lens as a function of object vergence. Magnification gain increases with objects at near from 17% to 26%, whereas the vergence at the principal plane of the crystalline lens changes by 3.04 D less than in the spectacle-corrected eye. In example 2, a 20-D myopia was corrected with a PL. The gain in magnification changed from 33% to 58% with nearer objects. The change in vergence at the principal plane of the crystalline lens with objects at near was much higher with the PL compared with the spectacle correction, which implies that the refractive change necessary for focusing objects at near distance is much higher in the PL correction.

CONCLUSIONS

Even if the predictability of postoperative refraction with PL is comparable or better than in other methods of correcting high or excessive ametropia, the effects of lateral magnification change and accommodation have to be considered to avoid image-size disparities (aniseikonia) and to maintain binocular vision, especially with monocular PL implantation and anisometropia.

Position of myopic iris-claw phakic intraocular lens by Scheimpflug photography and ultrasound biomicroscopy

PURPOSE

To evaluate the position of iris-claw phakic intraocular lens (ICPIOL) in highly myopic eyes by Scheimpflug photography (SP) and ultrasound biomicroscopy (UBM).

METHODS

Nine eyes of five patients aged 31+/-10 years with average spherical equivalent of -16.04+/-5.46 D (range -7.88 to - 22.88 D) were enrolled in this prospective study and implanted with Verisyse ICPIOLs (AMO). The anterior segment was evaluated by SP and UBM preoperatively and for at least 1 month postoperatively. The statistical significance may be questionable due to the limited number (nine) of eyes.

RESULTS

By SP and UBM, the distance between corneal endothelium and lens (anterior chamber depth) preoperatively was 3.10+/-0.14 and 3.07+/-0.11 mm, respectively; between ICPIOL and corneal endothelium (pseudo-anterior chamber depth), 1.88+/-0.09 and 1.99+/-0.12 mm, respectively; between lens and posterior surface of ICPIOL (IL), 0.76+/-0.13 and 0.67+/-0.06 mm, respectively; between superior optic edge and iris (SOEI), 0.23+/-0.23 and 0.58+/-0.24 mm, respectively; between inferior optic edge and iris (IOEI), 0.07+/-0.13 and 0.41+/-0.22 mm, respectively; between ICPIOL haptics and the angle of anterior chamber (HA), 0.90+/-0.17 and 1.45+/-0.13 mm, respectively. ACD was well correlated between the two methods, but PACD, IL, OEI, HA were not. The postoperative measures, except IL, were significantly different between the two methods.

CONCLUSION

The differences between measurements by SP and UBM reveal the ICPIOL's position variations with change of body position. Nevertheless, it seems adequate that space is maintained between ICPIOL and corneal endothelium, angle, and crystalline lens. The ICPIOL implanted in phakic eyes seems a safe alternative for treatment of high myopia.

Efficacité réfractive et tolérance de l’implant phaque myopique souple à fixation irienne Artiflex® dans la correction chirurgicale de la myopie forte : résultats à deux ans

INTRODUCTION

A new foldable version of an anterior chamber phakic lens designed to surgically correct high myopia was evaluated.

PATIENTS AND METHODS

A prospective study on the efficacy and tolerance of a foldable phakic intraocular iris-supported lens, designed to correct moderately high myopia, is presented in this article. Twenty-five eyes of 25 patients were implanted uneventfully using this lens, newly designed and called the Artiflex lens. This phakic intraocular lens is an upgraded foldable version of the Artisan (or Verisyse) lens. The follow-up was complete (24 months) for all Artiflex-treated eyes and the targeted postoperative refraction was emmetropia. Inclusion criteria were moderately high myopia ranging from -8 to -14 D, unchanged refraction for 2 years, total contact lenses wearing intolerance, refractive cylinder power no greater than 1.5 D, anterior chamber depth greater than 3 mm, and endothelial cell count greater than 2,200 cells/mm2.

RESULTS

The preoperative spherical equivalent was -9.70+/-2.37 D. The spherical equivalent was -1.07+/-0.84 D at 2 years postoperatively. The surgically induced astigmatism was 0.42 D x 67.4-degree axis. The percentage of eyes with an uncorrected visual acuity greater than or equal to 0.5 and 0.8 was 66.6% and 33.3%, respectively. Neither intra- nor postoperative complications were noted during the entire follow-up period. The mean endothelial cell count value was 2267+/-352 at 2 years postoperatively. The objective and subjective quality of vision was acceptable, associated with a high level of patient satisfaction.

DISCUSSION

The refractive results and tolerance of the Artiflex lens are satisfactory and seem to be as good as other phakic intraocular lens outcomes.

CONCLUSION

To correct moderately high myopia, the Artiflex lens seems to provide a suitable refractive efficacy and a quick visual recovery, secondary to a lowering of induced astigmatism. Furthermore, this phakic intraocular lens is associated with satisfactory safety and quality of vision at each milestone of the entire follow-up period.

Artisan iris-fixated toric phakic and aphakic intraocular lens implantation for the correction of astigmatic refractive error after radial keratotomy

We report 2 patients who had radial keratotomy (RK) to correct myopia. The first patient developed a postoperative hyperopic shift and cataract. Nine years post RK, she had intracapsular cataract extraction and implantation of an Artisan aphakic intraocular lens (IOL). Twenty years post RK, hyperopia and astigmatism progressed to +7.0 -5.75 x 100 with a best corrected visual acuity (BCVA) of 20/20. Due to contact lens intolerance, the Artisan aphakic IOL was exchanged for an Artisan toric aphakic IOL. Three months later, the BCVA was 20/20 with +1.0 -0.50 x 130. The second patient demonstrated residual myopic astigmatism 6 years after bilateral RK and had become contact-lens intolerant. An Artisan toric phakic IOL was implanted in both eyes. Four months later, the BCVA was 20/25 with a refraction of +0.25 -1.0 x 135 and 20/20 with a refraction of -1.0 x 40. Both patients were satisfied with the visual outcomes.

Ultrasound biomicroscopy study of the Verisyse aphakic intraocular lens combined with penetrating keratoplasty in pseudophakic bullous keratopathy

PURPOSE

To evaluate anterior segment modifications after penetrating keratoplasty (PKP), previous anterior chamber intraocular lens (IOL) removal, and Verisyse IOL (AMO) implantation over the iris or under the iris for the treatment of pseudophakic bullous keratopathy (PBK) using ultrasound biomicroscopy.

SETTING

Department of Ophthalmology, Poitiers University Hospital, Poitiers, France.

METHODS

A prospective randomized comparative case series included 27 patients (27 eyes) with PBK who had PKP and implantation of a Verisyse VRSA54 aphakic IOL. The IOL was implanted over the iris in 13 patients (Group A) and under the iris in a reversed position in 14 patients (Group B). Ultrasound biomicroscopy scans 6 months after surgery measured central anterior chamber depth (ACD), iris thickness (IT), distance of the haptics from the corneal endothelium (CED), distance of the haptics from the ciliary body (CBD), angle opening distance (AOD) 500 mum from the scleral spur (AOD500) and the iridocorneal angle theta on the 4 o'clock meridian lines (AOD3; AOD9; AOD12; AOD6/theta12, theta6, theta3, theta9).

RESULTS

No significant difference was found in IT, CBD, or AOD12 between Group A and Group B (P >.05). In Group B, the mean ACD was deeper by approximately 55% (P = .008); CED3 was larger by 69% (P = .0162), CED9 by 80% (P = .0128), AOD3 by 57% (P = .0309), AOD9 by 140% (P = .0057), and AOD6 by 44% (P = .0399); and theta3 was wider by 52% (P = .046), theta9 by 123% (P = .0068), theta12 by 50% (P = .0492), and theta6 by 81% (P = .0237).

CONCLUSION

Ultrasound biomicroscopy showed that in eyes that had PKP with Verisyse IOL enclavation to the posterior plane of the iris, which involved posterior translation of the iridal plane, the ACD was significantly deeper and the CED and AOD were significantly larger than in eyes with anterior enclavation of the IOL.

Endothelial Cell Loss After Toric Iris-fixated Phakic Intraocular Lens Implantation: Three-year Follow-up

PURPOSE

To study quantitative changes in endothelial cell count after implantation of the toric iris-fixated phakic intraocular lens.

METHODS

A prospective, non-randomized, self-controlled clinical trial was conducted of 40 eyes (28 myopic, 12 hyperopic) of 23 patients with high ametropia and astigmatism. Non-contact computer-assisted endothelial microscopy was performed before and 1, 2, and 3 years after surgery.

RESULTS

In the myopic group, mean preoperative endothelial cell count was 3179 +/- 531 cells/mm2 (range: 1800 to 3900 cells/mm2). The mean intra-individual endothelial cell loss was -1.83 +/- 2.25% (range: -9.09% to 0%) in the first year; -1.83 +/- 2.95% (range: -7.74% to 3.80%) in the second year; and -3.20 +/- 4.43% (range: -14.25% to 1.91%) three years after surgery, compared to preoperative values. In the hyperopic group, mean preoperative endothelial cell count was 3107 +/- 125 cells/mm2 (range: 2932 to 3300 cells/mm2). The mean endothelial cell loss was -1.63 +/- 1.76% (range: -3.23% to 1.67%) in the first year; -0.05 +/- 1.25% (range: -1.65% to 1.75%) in the second year; and -2.88 +/- 2.03% (range: -5.33% to -0.13%) three years after surgery, compared to preoperative values.

CONCLUSIONS

Annual cumulative cell loss was -1.9% for the myopic group and -1.6% for the hyperopic group, which is two to three times greater than physiological annual cell loss in normal eyes without surgery. An annual endothelial cell count analysis is highly recommended in every patient after iris-claw lens implantation to detect potential progressive cell loss at an early stage.

Use of Verisyse iris-supported phakic intraocular lens for myopia in keratoconic patients

We report 2 patients with stable keratoconus and high myopia who benefited from implantation of an iris-supported phakic intraocular lens (Verisyse, AMO) for correction of their refractive error. Both patients had a postoperative uncorrected visual acuity of 20/40. Endothelial cell density showed at most a 4% decrease, and no evidence of keratoconus progression was witnessed. The use of the Verisyse lens may be beneficial for certain keratoconic patients as an alternative step between rigid gas-permeable lenses and penetrating keratoplasty.

Iris-fixated toric phakic intraocular lens: Three-year follow-up

PURPOSE

To evaluate the 3-year safety, efficacy, predictability, and stability of iris-fixated toric phakic intraocular lens (pIOL) implantation for the correction of myopia or hyperopia with astigmatism.

SETTING

Department of Ophthalmology, Johannes Gutenberg University, Mainz, and Department of Ophthalmology, University Clinic, Bochum, Germany.

METHODS

A prospective clinical trial of 40 eyes of 23 patients with high ametropia and astigmatism was conducted. Best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity, refraction, astigmatism, intraocular pressure, slitlamp biomicroscopy, and indirect ophthalmoscopy were measured preoperatively and postoperatively.

RESULTS

Of the 40 eyes, 28 were myopic and 12 were hyperopic. Three years postoperatively, 70% of eyes were within +/-1.00 diopter (D) of the targeted refraction. In the myopic group, mean preoperative BSCVA was 20/40 and improved postoperatively to 20/25. Sixty-six percent of eyes gained 1 or more lines from the preoperative BSCVA. The mean cylinder decreased from -3.58 D +/- 1.26 (SD) preoperatively to -1.15 +/- 1.01 D postoperatively. In the hyperopic group, preoperative BSCVA was 20/25 and improved to 20/20 postoperatively. Thirty-six percent of eyes gained 1 or more lines from the preoperative BSCVA. The mean cylinder decreased from -3.37 +/- 0.88 D to -1.53 +/- 0.69 D postoperatively. The correction was stable in all eyes 3 years after surgery. No potentially sight-threatening complications occurred.

CONCLUSION

The 3-year follow-up showed the iris-fixated toric pIOL was effective in correcting high ametropia and astigmatism.

Long-Term Complications of Iris-Claw Phakic Intraocular Lens Implantation in Weill-Marchesani Syndrome

PURPOSE

This study was designed to report the long-term complications of iris-claw phakic intraocular lens implantation in a patient with Weill-Marchesani syndrome.

METHODS

Case report and literature review.

RESULTS

A 26-year-old man with a history of glaucoma had bilateral phakic lens implantation for high myopia 10 years previously. Two years later, the left implant dislocated and was repositioned. Slit-lamp examination of both eyes revealed phakic implants of the iris-claw variety. There were moderate iridocorneal adhesions in the areas in which the lens haptics pinched the iris in both eyes and moderate epithelial and stromal edema over the temporal one-third of the left cornea. The crystalline lenses were clear with 3+phacodonesis OU. Dilated fundus examinations revealed bilateral severe optic nerve cupping. Crystalline lens diameters were measured at 7.5mm in the right eye and 8 mm in the left. Anterior chamber depths were 2.63 mm OD and 2.40 mm OS. Specular microscopy revealed central endothelial cell counts of 1133 and 587 cells/mm OD and OS, respectively. Axial lengths were 23.3 mm OD and 25 mm OS. Gonioscopic examination revealed bilateral angle closure with marked peripheral anterior synechiae. Based on our findings of short stature, shortened and thickened fingers, relatively normal axial length, microspherophakia, high myopia, and glaucoma, we diagnosed the patient with Weill-Marchesani syndrome.

CONCLUSION

Iris claw-lens phakic lenses may be an effective surgical alternative to correct high myopia in select patients; however, it may produce long-term complications in eyes with specific features.

Scheimpflug Biometry of the Anterior Segment After Implantation of Foldable Iris-fixated Lenses

PURPOSE

To evaluate intraocular dimensions of the anterior segment of myopic phakic eyes after implantation of foldable iris-fixated lenses.

METHODS

Seventeen myopic eyes that received a foldable iris-fixated phakic intraocular lens (PIOL) were assessed. Distances between the cornea and the IOL-optic edge and between the IOL optic and the crystalline lens were evaluated using Scheimpflug photography 3 months postoperatively.

RESULTS

The average postoperative distance between the central corneal endothelium and the anterior surface of the IOL was 2.01 +/- 0.26 mm. The distance between the corneal endothelium and the peripheral edge of the IOL averaged 1.32 +/- 0.18 mm at the 12 o'clock position and 1.34 +/- 0.21 mm at the 6 o'clock position. The distance between the crystalline lens and the posterior surface of the IOL averaged 0.73 +/- 0.09 mm.

CONCLUSIONS

The high quality of the three-dimensional Scheimpflug images allowed measurements of intraocular distances in PIOL implanted eyes. Distances between the foldable iris-fixated IOL and crucial surrounding tissues could be determined 3 months postoperatively.

Toric phakic intraocular lens for the correction of hyperopia and astigmatism

PURPOSE

To evaluate the Artisan toric phakic intraocular lens (pIOL) for the correction of hyperopia and astigmatism.

SETTING

Department of Ophthalmology, Erasmus MC, Rotterdam, The Netherlands, and Department of Ophthalmology, Sint Truiden, Belgium.

METHODS

In this prospective study of 47 eyes of 28 patients with hyperopia and astigmatism, Artisan toric pIOLs were implanted between April 1999 and June 2004. Uncorrected visual acuity (UCVA), best corrected visual acuity, refraction, astigmatism, safety, and predictability were analyzed. Change in astigmatism was analyzed with vector analysis. Refractive cylinders are expressed in minus form.

RESULTS

Mean preoperative spherical equivalent was +4.33 diopters (D) +/- 2.26 (SD). Mean follow-up was 11.1 months (range 6 to 36 months). A gain of 1 or more lines in best spectacle-corrected visual acuity (BSCVA) was seen in 36.2%. Safety index and efficacy index after 6 months were 1.06 and 0.87, respectively. The mean postoperative astigmatism at 6 months was 0.19 D at an axis of 144 degrees. At 6 months, about three quarters (76.6%) of the eyes had a UCVA of 20/40 or better. One eye lost 2 lines of BSCVA. In 1 eye, the lens position had to be changed because of a large axis misalignment. No serious complications developed in any of the treated eyes during follow-up.

CONCLUSIONS

Artisan toric pIOLs can correct moderate to high hyperopia combined with astigmatism with good refractive results. In this study, there were no serious complications. However, the predictability of the refractive results appeared to be lower than those in the correction of myopia and astigmatism with toric Artisan lenses.

The "Sandwich Technique" for Iris-fixated Phakic Intraocular Lens Implantation

PURPOSE

To describe a new technique of implantation of the Artisan/Verisyse phakic intraocular lens (PIOL).

METHODS

After PIOL insertion into the anterior chamber, a bolus of a high viscosity ophthalmic viscosurgical device (OVD) is placed over the optic, separating it widely from the endothelium.

RESULTS

The technique decreases the chance of endothelial damage during enclavation.

CONCLUSIONS

A bolus of a high viscosity OVD placed on the anterior surface of the Artisan/Verisyse PIOL may make enclavation safer.

Implantation of Verisyse Phakic Intraocular Lens to Correct Myopic Refractive Error After Penetrating Keratoplasty in Pseudophakic Eyes

PURPOSE

We report 2 cases in which a Verisyse phakic intraocular lens (PIOL) was used to successfully treat high myopia after penetrating keratoplasty (PK) in pseudophakic patients.

METHODS

Case 1 involved a 69-year-old pseudophakic man with a manifest refraction (MR) of -6.50 + 1.75 x 048 and a best spectacle corrected visual acuity (BSCVA) of 20/40 approximately 16 months after PK in the right eye. Case 2 was a 78-year-old pseudophakic man who had an MR of -9.00 + 5.75 x 132 with a BSCVA of 20/100 approximately 24 months after PK in the left eye.

RESULTS

In case 1, 10 months after Verisyse PIOL implantation, the MR was pl +2.00 x 135 with a BSCVA of 20/30. Endothelial cell density (ECD) in this patient decreased from 1926.1 to 815.3 cells/mm over 17 months. In case 2, 24 months after Verisyse PIOL implantation, the MR was -3.25 + 3.50 x 105 with a BSCVA of 20/60. ECD in this patient decreased from 2108.4 to 753.8 cells/mm in 30 months.

CONCLUSION

The Verisyse PIOL may provide an alternative method to correct high myopia for anisometropia in pseudophakic patients after PK. In this report, PIOL implantation was associated with a decrease in ECD. Further studies are required to determine the long-term effects and ultimate safety of PIOL placement on the integrity of the cornea endothelium after corneal transplant in pseudophakic patients.

Short-term Follow-up after Implantation of a Foldable Iris-Fixated Intraocular Lens in Phakic Eyes

OBJECTIVE

To evaluate efficiency, predictability, stability, complications, and patient satisfaction after implantation of a foldable iris-fixated phakic intraocular lens (PIOL) for the correction of myopia.

DESIGN

Prospective, nonrandomized, comparative (self-controlled) trial.

PARTICIPANTS

Forty-one eyes of 22 myopic patients aged 18 to 56 years (mean, 36 years) with average sphere of -8.2+/-2.01 diopters (D; range, -12.25 to -3.75 D) and average preoperative cylinder of -0.90+/-0.62 D (range, -2.50 to 0.00 D) were enrolled in this prospective study.

METHODS

All eyes underwent implantation of a foldable iris-fixated PIOL with an optical zone of 6.0 mm. The follow-up was 6 months in all cases. Phakic intraocular lenses were available in powers ranging from -2.0 D to -12.0 D.

MAIN OUTCOME MEASURES

The main parameters assessed were best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity, refraction, endothelial cell count, intraocular pressure, slit-lamp biomicroscopy, and indirect ophthalmoscopy.

RESULTS

At 6 months' follow-up, no eyes experienced a loss in BSCVA and 78% gained 1 or more lines of their preoperative BSCVA. Uncorrected visual acuity was significantly improved, with 82% of eyes reaching 20/25 or better. There was a significant reduction in spherical errors in all patients after surgery. Ninety-one percent of eyes were within +/-0.50 D of target refraction. A slight loss of endothelial cells (2.3 %) was observed 6 months after surgery. There were no intraoperative complications. In the postoperative follow-up, however, pigment precipitates were noted in 5 eyes of 4 patients.

CONCLUSIONS

At short-term follow-up, the implantation of the foldable iris-fixated PIOL proved to be effective and predictable for the correction of myopia in phakic eyes. However, longer follow-up with larger numbers of patients is necessary to evaluate long-term complications.

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.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses which are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for posterior chamber lenses these are mainly cataract formation and pigment dispersion. RLE is preferable in cases of high ametropia in which the natural lens has lost its accommodative effect. The main complications for myopic RLA include retinal detachment, while hyperopic refractive lens exchange may be associated with surgical problems in the narrower anterior eye segment.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

Artisan Phakic Intraocular Lens for Correcting High Myopia

OBJECTIVES

To evaluate the safety indexes and efficacy of Artisan phakic intraocular lens (IOL) for the correction of high myopia.

METHODS

Retrospective interventional case series reports. Thirty-one eyes (22 patients) with myopia from -5.25 to -19.00 diopters underwent implantation of an Artisan phakic IOL. Follow-up examinations were performed at 1 day, 1 week, 1 month, and 3 months. The following parameters were recorded: manifest refraction, slit-lamp examination, applanation tonometry, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), complications or adverse reactions. The primary variable was the refractive outcome at 3 months. Secondary variables were change in BSCVA, and efficacy and safety indexes.

RESULTS

At 3 months, mean spherical equivalent was -0.50 +/- 0.36 diopters (range, -1.25 - plano). In 29 eyes (93.5%) UCVA was 6/12 or better; the other three eyes had UCVA of 6/15. The difference between preoperative and 1 week postoperative BSCVA was not statistically significant (p = 0.25). Comparison of BSCVA at 1 week and at 1 month was statistically significant (p = 0.05); this difference was even more significant at 3 months (p = 0.01). The BSCVA remained the same or improved for all the eyes. BSCVA for 20 eyes (64.5%) had improved one or more lines in visual acuity. Mean endothelial cell loss at 3 months was 3.96%.

CONCLUSION

The Artisan lens is a safe, predictable, and efficacious method to correct high myopia. Postoperative gain in BSCVA was achieved for the majority of eyes. Future study to assess safety indexes and risk of complications is required with long-term follow-up.

Correction of Myopia of 7 to 24 Diopters With the Artisan Phakic Intraocular Lens: Two-year Follow-up

PURPOSE

To evaluate the safety and efficacy of the iris claw phakic intraocular lens (Artisan; Ophtec BV, Groningen, The Netherlands) in patients with high myopia.

METHODS

Between May 1999 and July 2001, 93 Artisan phakic intraocular lenses (IOLs) were implanted in 60 patients affected by high myopia. All patients underwent 24-month follow-up. The power of the lenses ranged from -7.5 to -22.0 diopters (D). Patients were divided into two groups: group 1 (68 eyes), myopia -6.75 to -15.50 D (SE), and group 2 (25 eyes), myopia -16.0 to -23.0 D (SE). Pre- and postoperative patient evaluation included manifest and cycloplegic refractions, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), endothelial cell count, intraocular pressure, complication rate, safety, and efficacy.

RESULTS

At 4 months, 83.8% (57/68) (group 1, myopia -6.75 to -15.50 D) and 68% (17/25) (group 2, myopia -16.0 to -23.0 D) of eyes achieved UCVA of > or =20/40. The BSCVA remained the same or improved in 100% of eyes. After 4 months, 69.1% (47/68) of eyes in group 1 and 52% (13/25) of eyes in group 2 were within +/-1.00 D of the desired refraction; the mean refraction was stable between 4 and 24 months. Of the intraoperative complications, 69.2% were observed in the first 25 lenses implanted; postoperative complications included iris atrophy in 11.8% (11/93), lens decentration in 5.4% (5/93), and night glare in 6.4% (6/93) of eyes. No IOLs were removed. Mean endothelial cell loss was 2.8% at 4 months, 3.9% at 12 months, and 5.4% at 24 months.

CONCLUSIONS

Our results regarding implantation of the Artisan phakic IOL confirm that these lenses are safe and effective for the correction of high myopia, with a stable refractive outcome but with a higher than normal rate of endothelial cell loss during 2-year follow-up.

Anterior chamber width measurement by high-speed optical coherence tomography

OBJECTIVE

To measure anterior chamber (AC) width and other dimensions relevant to the sizing of phakic intraocular lenses (IOLs) with a high-speed optical coherence tomography (OCT) system.

DESIGN

Cross-sectional observational study.

PARTICIPANTS

Both eyes of 20 normal volunteers.

METHODS

A novel high-speed (4000 axial scans/second) OCT prototype was developed for anterior segment scanning. The system uses long wavelength (1310 nm) for deeper angle penetration, rectangular scanning for undistorted imaging, and short image acquisition time (0.125 seconds) to reduce motion error. Three horizontal cross-sectional OCT images (15.5 mm wide and 6 mm deep) of the anterior segment were obtained from each eye with real-time image display to guide centration on the corneal apex. Image processing software was developed to correct for image warping resulting from index transitions. Anterior chamber dimensions were measured using computer calipers by 3 expert raters (ophthalmologists). Analysis of variance was used to determine interrater, interimage, right versus left eye, and intersubject standard deviation (SD) of OCT measurements.

MAIN OUTCOME MEASURES

Anterior chamber width (recess to recess), AC depth, and crystalline lens vault as measured by OCT; external white-to-white (WTW) corneal diameter (CD) as measured by Holladay-Godwin gauge.

RESULTS

The mean AC width was 12.53+/-0.47 mm (intereye SD), and the mean corneal diameter was 11.78+/-0.57 mm. Optical coherence tomography measurement of AC width has good repeatability from image to image (SD, 0.134 mm), but there was significant difference between raters (SD, 0.215 mm). Estimation of AC width from WTW CD by linear regression was relatively inaccurate (residual SD, 0.41 mm). The mean AC depth was 2.99+/-0.323 mm (intereye SD), with repeatability of less than 0.001 mm (interimage SD), and the mean crystalline lens vault was 0.39+/-0.27 mm with 0.023 mm repeatability.

CONCLUSIONS

Reproducible OCT AC biometry was demonstrated using a high-speed OCT prototype. Further improvement in reproducibility may be achieved by automating the measurements with a computer. Direct OCT AC width measurement may improve sizing of angle-supported AC IOLs over conventional estimation by WTW CD. The measurement of AC depth and lens vault also may be useful for other types of phakic AC IOLs.

Artisan iris-claw phakic intraocular lens followed by laser in situ keratomileusis for high hyperopia

PURPOSE

To evaluate safety, efficacy, predictability, stability, complications, and patient satisfaction after Artisan phakic intraocular lens (IOL) implantation followed by laser in situ keratomileusis (LASIK) for the correction of high hyperopia.

SETTING

Instituto Oftalmólogico de Alicante, Alicante, Spain.

METHODS

This prospective trial included 39 eyes with a mean preoperative spherical equivalent (SE) of 7.39 diopters (D) +/- 1.30 (SD) and a cylinder between 0 and -4.25 D. The Artisan iris-fixated phakic IOL (Ophtec) for hyperopia was implanted, and LASIK was performed 6 to 8 months later. The best corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), refraction, endothelial cell loss (ECL), endothelium morphologic analysis, and patient satisfaction were recorded. The minimum follow-up was 12 months.

RESULTS

At 1 year, 37 eyes (94.9%) were within +/-1.00 D of emmetropia and 31 eyes (79.5%) were within +/-0.50 D. Thirty-five eyes (89.7%) achieved a UCVA of 0.5 or better. There was a statistically significant decrease in BCVA after phakic IOL implantation, but this effect was corrected after LASIK. Nine eyes (23.1%) lost 1 line of BCVA; 7 eyes (17.9%) gained at least 1 line. One eye (2.6%) showed a change in SE greater than 1.0 D over the follow-up period. The mean ECL was 10.9%, but morphologic analysis suggested no additional damage caused by LASIK over that produced by phakic IOL surgery. Overall patient satisfaction was high.

CONCLUSIONS

The combination of Artisan phakic IOL implantation and LASIK safely, predictably, and effectively reduced high hyperopia. A loss of 1 line of BCVA should be expected in about one third of eyes implanted with this IOL. Halos and glare at night remain a potential problem.

Long-term results of implantation of phakic posterior chamber intraocular lenses

PURPOSE

To study the incidence and progression of lens opacification after implantation of phakic posterior chamber intraocular lenses for myopia and its correlation with vaulting and endothelial cell density (ECD).

SETTING

Department of Ophthalmology, University of Vienna Medical School, Vienna, Austria.

METHODS

An implantable contact lens (ICL V4, Staar Surgical Inc.) was inserted in 76 myopic eyes. Patients were prospectively followed preoperatively and at 1, 3, 6, 12, 24, and 36 months. The uncorrected visual acuity and best corrected visual acuity (BCVA) were determined. Vaulting was measured optically with a Jaeger II pachymeter, and the crystalline lens was examined at the slitlamp for the presence and characteristics of opacification. Endothelial cell morphometry was performed by specular microscopy, and the ECD was calculated. Eyes in which lens opacification developed were followed for at least 12 months to determine the degree and course of visual impairment.

RESULTS

Lens opacification occurred in 11 eyes (14.5%). Opacification was correlated with intraoperative trauma to the crystalline lens, age older than 50 years, and decreased ECD values throughout the observation period. Vaulting of the ICL did not correlate with the risk for lens opacification. After onset of lens opacification, 6 eyes (55%) had a stable BCVA within +/-0.5 lines and 5 eyes had progressive opacification, losing between 3.5 lines and 0.5 lines (mean 1.8 lines +/- 1.1 [SD]). Three eyes (3.9%) in the progressive group had a 1- to 2-line loss of BCVA over preoperative values and subsequently had cataract surgery.

CONCLUSIONS

Risk factors for lens opacification after implantation of the model V4 ICL included intraoperative trauma to the crystalline lens and older age. Decreased ECD in eyes with opacification suggests ongoing inflammation as a cause. Patients younger than 45 years may have a significantly lower incidence of opacification.

Phakic posterior chamber intraocular lens for high myopia

PURPOSE

To evaluate the efficacy, predictability, stability, and safety of the surgical correction of high myopia using a phakic posterior chamber intraocular lens (PPC IOL).

SETTING

Centro Oftalmológico de Valencia-CEOVAL, Valencia, Venezuela.

METHODS

A retrospective study was performed to analyze 18 eyes of 12 patients who had implantation of a modified PPC IOL, the implantable contact lens (ICL), for the treatment of high myopia. The target postoperative spherical equivalent (SE) refraction was emmetropia.

RESULTS

The mean follow-up was 26.6 months +/- 11.3 (SD) (range 12 to 36 months). The mean preoperative SE was -15.27 +/- 3.47 diopters (D) (range -10.0 to -21.25 D) and the mean postoperative SE, -0.62 +/- 0.81 D (range -2.75 to +0.75 D). Eleven eyes (61.1%) had an SE within +/-1.00 D of emmetropia. The best spectacle-corrected visual acuity was maintained or improved in all except 1 eye, which lost more than 2 lines of Snellen visual acuity. Two eyes (11.1%) developed pupillary block the first day after surgery. Four eyes (22.2%) had moderate pigmentary dispersion. Two eyes (11.1%) had lens opacification, 1 with mild peripheral anterior capsule opacification and the other eye with central anterior subcapsular opacification. One eye (5.5%) had a significant decrease in anterior chamber depth after surgery.

CONCLUSIONS

Implantation of an ICL was effective for the correction of high myopia. Predictability must be improved and the long-term safety of the ICL determined. The main concerns over potential cataract formation, pigmentary dispersion, and angle-closure glaucoma remain.

Artisan aphakic intraocular lens in children with subluxated crystalline lenses

PURPOSE

To evaluate the results of Artisan (Ophtec) aphakic intraocular lens (IOL) implantation in children with idiopathic subluxated lenses.

SETTING

Department of Ophthalmology, Soroka University Medical Center, Beer-Sheva, Israel.

METHODS

This retrospective small case series comprised 4 eyes (3 children) with idiopathic essential subluxated lenses that had lens washout, lens capsule removal, Artisan IOL implantation, and peripheral iridectomy. The indications for surgery were reduced visual acuity and monocular diplopia. The main outcome measures were postoperative refraction and change in best corrected visual acuity (BCVA).

RESULTS

The postoperative follow-up ranged from 8 to 10 months. After surgery, the BCVA was 6/12 or better in the 3 cases that could be recorded. Visual acuity improved by 2 or more Snellen lines in all 4 eyes. The postoperative spherical equivalent was within +/-1.00 diopter in all cases. No significant postoperative complications were observed.

CONCLUSIONS

In 4 eyes with a subluxated crystalline lens, implantation of an Artisan aphakic IOL improved visual acuity. Studies with a larger number of patients and longer follow-up are necessary to confirm these results.

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.