Correction of Myopia of 7 to 24 Diopters with the Artisan Phakic Intraocular Lens: Two-Year Follow-Up

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

Stefano Benedetti, MD; Virna Casamenti, MD; Lucio Marcaccio, MD; Carlo Brogioni, MD; Vincenzo Assetto, MD

ore and more often people suffering from myopia, ABSTRACT especially severe myopia, have expressed the de- PURPOSE: To evaluate the safety and effi cacy of the iris M sire or need to change their refractive status. Nu- claw phakic intraocular lens (Artisan; Ophtec BV, Gronin- merous treatment options are available; however, choosing gen, The Netherlands) in patients with high myopia. the proper treatment depends on a series of factors relating to the individual characteristics of the patient’s myopia. Two METHODS: Between May 1999 and July 2001, 93 Ar- important factors to consider when choosing the correct treat- tisan phakic intraocular lenses (IOLs) were implanted in ment are the anatomical structure and function of the treat- 60 patients affected by high myopia. All p atients underwent 24-month follow-up. The power of the lenses able eye and the specifi c work and leisure requirements of the ranged from 7.5 to 22.0 diopters (D). Patients individual (eg, sports, driving, etc). were divided into two groups: group 1 (68 eyes), myo- Developments and refi nement of excimer laser technology pia 6.75 to 15.50 D (SE), and group 2 (25 eyes), have brought the corneal approach into the limelight. Howev- myopia 16.0 to 23.0 D (SE). Pre- and postoperative er, it has been found that correction instability, haze, loss of patient evaluation included manifest and cycloplegic refractions, uncorrected visual acuity (UCVA), best spec- lines of best spectacle-corrected visual acuity (BSCVA), and tacle-corrected visual acuity (BSCVA), endothelial cell corneal ectasia are potential complications that can result. count, intraocular pressure, complication rate, safety, Furthermore, current use of the confocal microscope permits and effi cacy. a close-up study of cornea tissue characteristics, which could suggest potential problems thereby contraindicating laser RESULTS: At 4 months, 83.8% (57/68) (group 1, myo- treatment. Stromal microdots, Bowman’s or epithelial altera- pia 6.75 to 15.50 D) and 68% (17/25) (group 2, myopia 16.0 to 23.0 D) of eyes achieved UCVA of tions, etc, reveal a poor cornea quality frequently observed 20/40. The BSCVA remained the same or improved in in patients with high myopia especially after many years of 100% of eyes. After 4 months, 69.1% (47/68) of eyes in contact lens use. group 1 and 52% (13/25) of eyes in group 2 were within Implanting an intraocular lens in phakic eyes is one of the 1.00 D of the desired refraction; the mean refraction most satisfactory surgical procedures for the correction of was stable between 4 and 24 months. Of the intraopera- 1,2 3 tive complications, 69.2% were observed in the fi rst 25 high myopia. In the 1950s, Strampelli and Barraquer intro- lenses implanted; postoperative complications included duced phakic intraocular lenses (PIOLs) to correct refractive iris atrophy in 11.8% (11/93), lens decentration in 5.4% errors; since then, several PIOLs have been developed. Pres- (5/93), and night glare in 6.4% (6/93) of eyes. No IOLs ently, three different major designs exist: posterior chamber were removed. Mean endothelial cell loss was 2.8% at 4 PIOLs, anterior chamber angle-supported PIOLs, and anterior months, 3.9% at 12 months, and 5.4% at 24 months. chamber iris-supported PIOLs. CONCLUSIONS: Our results regarding implantation of The fi rst iris claw lens was developed in 1978 for the cor- 4 the Artisan phakic IOL confi rm that these lenses are rection of aphakia following cataract surgery. In 1986, it was safe and effective for the correction of high myopia, with modifi ed into a biconcave design for the correction of myo- a stable refractive outcome but with a higher than normal rate of endothelial cell loss during 2-year follow-up. [J Refract Surg. 2005;21:xxx-xxx.] From Casa di Cura Villa Igea, Ancona, Italy. The authors have no proprietary interest in the materials presented herein. Correspondence: Stefano Benedetti, MD, Casa di Cura Villa Igea, via Maggini 200, 60100 Ancona, Italy. Tel: 3907155160; Fax: 3907153990, E-mail: [email protected] Received: December 15, 2003 Accepted: August 4, 2004

Journal of Refractive Surgery Volume 21 March/April 2005 1 Correction of High Myopia With the Artisan PIOL/Benedetti et al

TABLE 1 TABLE 2 Demographics of 60 Patients Who Visual Acuity and Refractive Data of Underwent Surgical Correction of Groups 1 (Myopia 6.75 to 15.5 D) High Myopia With the Iris Claw and 2 (Myopia 16.0 to 23.0 D)* Phakic Intraocular Lens Parameter Group 1 Group 2 Parameter No. Patients (%) Refraction (spherical 11.82.4 18.92.0 Bilateral cases 33 (55) equivalent) ( 6.75 to 15.5) ( 16 to 23.0) Unilateral cases 27 (45) Cylinder 1.25 0.93 1.58 0.95 (0 to 4) (0 to 3) Women 39 (65) UCVA 0.030.02 0.010.005 Men 21 (35) (0.01 to 0.075) (0.01 to 0.025) Mean age (range) (y) 35 (22 to 52) BSCVA 0.860.18 0.620.19 (0.2 to 1) (0.3 to 1) Group 1 (lens model 204) 68 eyes (73.1) (6.75 to 15.5 D myopia) UCVA = uncorrected visual acuity, BSCVA = best spectacle-corrected visual acuity Group 2 (lens model 206) 25 eyes (26.9) *Data represented as meanstandard deviation (range). (16.0 to 23.0 D myopia) pia5; in 1991, the Artisan myopia lens was redesigned Demographics and refractive data of the 60 patients are in a convex-concave conﬁ guration.6 In 1997, a new summarized in Tables 1 and 2. Inclusion criteria was age model with a 6.0-mm optic was introduced to address 21 years with high myopia (6.00 D), myopia with a potential night glare and halos. variation in spherical equivalent refraction 0.50 D in The current study evaluated our clinical and refractive the 18 months before surgery, BSCVA of at least 20/200, results of the Artisan phakic IOL (Ophtec BV, Groningen, central anterior chamber depth 3.00 mm, endothelial The Netherlands) for the correction of high myopia. cell count 2000 cells/mm2, problems with contact lens use or wearing spectacles, contraindication for PATIENTS AND METHODS laser in situ keratomileusis (LASIK) on the basis of pachymetric data or other corneal characteristics (re- PATIENTS vealed through confocal microscopy), no uveitis, and Between May 1999 and July 2001, 93 eyes of 60 pa- intraocular pressure 20 mmHg. tients (21 men and 39 women) underwent implanta- Exclusion criteria were systemic disease, previous tion of an Artisan PIOL by the same surgeon (S.B.) at corneal or intraocular surgery, anterior segment patho- Casa di Cura Villa Igea, Ancona, Italy. In 33 patients, logic condition, glaucoma, and pre-existing macular both eyes were operated on. Patient age ranged from degeneration or retinopathy. 22 to 52 years (mean: 357 years) and the preopera- The risks of this operation were explained, and writ- tive refractive error ranged from 6.75 diopters (D) to ten informed consent was obtained from all patients 23.0 D (mean: 13.73.8 D). Fifty-eight (97%) pa- before surgery. tients wore contact lenses. Patients were divided into two groups—group 1 in- PREOPERATIVE EXAMINATION cluded those patients with myopia 6.75 to 15.50 D Preoperative examination included UCVA and (SE), and group 2 included patients with myopia mea- BSCVA, manifest and cycloplegic refraction, slit-lamp suring 16.0 to 23.0 D (SE). Lens model 204 (with 6.0- examination, tonometry (Topcon CT 80 computer- mm optical zone) was implanted in group 1 and model ized tonometer, Tokyo, Japan), keratometry (Nidek 206 (with 5.00-mm optic) was implanted in group 2. ARK-700), pupil diameter under low light conditions The mean preoperative refractive error was (Colvard pupillometer), white-to-white measurement 11.82.4 D in group 1 and 18.92.0 D in group 2. of the limbus (Orbscan II, version 3.0; Bausch & Lomb, Preoperative uncorrected visual acuity (UCVA) was Rochester, NY), iris evaluation (vaulting, position, col- 20/20 in all eyes; preoperative BSCVA was 20/20 in or, and thickness), and indirect ophthalmoscopy. Best 31 (45.6%) of 68 eyes in group 1 and in 2 (8%) of 25 spectacle-corrected visual acuity was measured under eyes in group 2; the mean cylinder was 1.250.93 D standard conditions using the Snellen chart; visual and 1.580.95 D in groups 1 and 2, respectively. The acuity was computed in decimal notation. mean endothelial cell count was 2658360 cells/mm2. The following complementary examinations were

2 journalofrefractivesurgery.com Correction of High Myopia With the Artisan PIOL/Benedetti et al

Figure 1. Distribution of IOL power in 93 10 eyes of 60 patients with high myopia.

4 No. Eyes

-7 -8 -9 6 7 9 1 1 -7.5 -8.5 -9.5 -10 -11 -12 -13 -14 -15 - 6.5 -1 -18 - -20 -21 -22 -10.5 -11.5 -12.5 -13.5 -14.5 -15.5 -1 -17.5 -18.5 -19.5 -20.5 -21.5 IOL power (D)

performed: videokeratography (Keratron, Optikon, lated using van der Heijde's formula7,8 and based on Rome, Italy), elevation and curvature corneal maps the refractive power of the cornea (mean corneal cur- (Orbscan II, version 3.0), central corneal ultrasound vature, K), adjusted anterior chamber depth (ACD, 0.8 pachymetry (DGH-500), axial length and anterior mm), and the patient’s spherical equivalent refractive chamber depth with ultrasonic biometer (Humphrey, error (spectacle correction at a 12.0-mm vertex). The model 820), color and contrast sensitivity (MAV-SIFI), mean PIOL power implanted was 13.53.2 D (range: confocal microscopy (Confoscan II, Nidek Technolo- 7.5 to 22.0 D) (Fig 1). gies), and central endothelial cell count. Endothelial images were obtained using the SP8000 Noncontact SURGICAL PROCEDURE Specular Microscope (Konan, Hyogo, Japan) and the Surgery was performed by the same surgeon (S.B.), cells were analyzed using the “dot method,” mark- and the surgical protocol was the same in all cases. Two ing the centers of approximately 80 contiguous cells. days before surgery, norfl oxacin 0.3%, dexamethasone From analyzed cells, the software gave values for the 0.2%, diclofenac 0.1%, and gentamicin 0.3% were morphometric parameters including cell density, administered four times a day topically. To achieve mean cell area, coeffi cient of variation (standard de- stable intraoperative myosis, pilocarpine eye drops 2% viation of cell area/mean cell area), and the percent- were instilled twice a day the day before surgery and age of hexagonal cells. 30 minutes before surgery. All procedures were performed under periocular anesthesia (6 mL of a propor- ARTISAN MYOPIA LENS tional combination of lidocaine 2%, mepivacaine 1%, The Artisan PIOLs used in the study (models 206 and and mucopolisacaridase), except two cases performed 204) are convex-concave, iris fi xated IOLs, designed by under general anesthesia. Jan Worst, MD, and manufactured by Ophtec BV, Gron- A scleral tunnel incision was made at 12 o’clock with ingen, The Netherlands. The biomaterial of this one- a 5.5- or 6.5-mm width depending on the diameter of the piece compression molded lens is CQ-UV absorbing lens, and two lateral paracenteses in the cornea were per- polymethylmethacrylate. In both PIOL types, the over- formed at 10 o’clock and 2 o’clock with a 1.5-mm width. all length is 8.5 mm, whereas the thickness depends The anterior chamber was washed with acetylcholine of the refractive power, increasing with the negative and fi lled with a viscoelastic substance (Healon). The power of the IOL; lens model 204, available in powers lens was inserted from the 12 o’clock position and rotat- from 3.00 to 15.50 D, has a 6.0-mm diameter optic, ed into a horizontal position. The lens haptic enclavated and lens model 206, available in powers from 3.00 to a fold of midperipheral iris stroma using an enclavation 23.50 D, has a 5.0-mm diameter optic. needle at 3 and 9 o’clock meridians to achieve a perfect Lens model 204 was implanted in group 1 (myopia centration of the lens (Fig 2). A peripheral surgical iri- 6.75 to 15.50 D) and model 206 in group 2 (myo- dectomy was performed at the 12 o’clock meridian to pia 16.0 to 23.0 D). The haptics of the Artisan PIOL prevent pupillary block glaucoma. All viscoelastic mate- consist of two diametrically opposed fl exible arms, as rial was carefully removed by manual irrigation to avoid an extension of the body of the lens; the two haptics postoperative ocular hypertension and the incision was fi xate the lens on the iris by enclavation of midperiph- closed with 10/0 nylon continuous suture. eral immobile iris stroma. All patients received a subconjuntival injection of be- The power of the PIOL to be implanted was calcu- tamethasone and gentamicin at the end of the procedure.

Journal of Refractive Surgery Volume 21 March/April 2005 3 Correction of High Myopia With the Artisan PIOL/Benedetti et al

(25%) eyes achieved UCVA of 20/20 and 57 (83.8%) eyes 20/40; in group 2 (myopia 16.0 to 23.0 D), 2 (8%) eyes achieved UCVA of 20/20 and 17 (68%) eyes 20/40; none achieved UCVA 20/200. Pre- and postoperative BSCVA are shown in Figure 4. Preoperatively, 31 (45.6%) eyes in group 1 and 2 (8%) eyes in group 2 had BSCVA 20/20; at 4 months, 54 (79.4%) eyes in group 1 and 9 (36%) eyes in group 2 achieved this acuity. In group 1, after 4 months, BSCVA 20/32 was achieved in 66 (97%) eyes and 20/50 in 68 (100%) eyes; in group 2, BSCVA 20/32 was achieved in 24 (96%) eyes and 20/50 in 25 (100%) eyes; none achieved BSCVA 20/60. Postoperative BSCVA was Figure 2. Postoperative appearance of the Artisan PIOL. Enclavation of signifi cantly better than preoperative values at all ex- the iris is present at 3:30 and 9:30 positions. An iridectomy is noted aminations (t test, P.05). No signifi cant differences in at 12:00. UCVA or BSCVA were noted at any time after surgery, denoting the stability of visual acuity postoperatively. Postoperative treatment included topical betameth- Best spectacle-corrected visual acuity remained the asone 0.2% and chloramphenicol 0.5% (Betabioptal; same or improved in 100% of eyes (n=93) (Fig 5). Farmila-Thèa) every 4 hours for 1 week and tapered The effi cacy index in group 1 was 0.79 at 4 months, over 4 weeks. 0.82 at 12 months, and 0.84 at 24 months, and 0.87 at 4 and 12 months and 0.90 at 24 months in group 2. The FOLLOW-UP safety index in group 1 was 1.10 at 4 months, 1.09 at 12 All patients were examined on the fi rst postoperative months, and 1.12 at 24 months; in group 2, it was 1.40 at day, and at 1, 3, and 6 weeks after surgery; examination 4 months, 1.42 at 12 months, and 1.39 at 24 months. schedules were then continued at 4, 12, and 24 months. Each postoperative examination included visual acu- REFRACTION ity, manifest and cycloplegic refractions, tonometry, slit- The mean preoperative spherical equivalent refrac- lamp examination, endothelial specular microscopy, and tion was 11.892.4 D (range: 6.75 to 15.5 D) in indirect ophthalmoscopy. group 1 and 18.922.04 D (range: 16.5 to 23.0 D) in The visual acuity examination included the safety group 2. The mean postoperative spherical equivalent index (ratio of mean postoperative BSCVA over mean refraction was 0.800.80 at 4 months, 0.890.77 preoperative BSCVA) and the effi cacy index (ratio of at 12 months, and 0.910.77 at 24 months for group the mean postoperative UCVA to the mean preopera- 1, and 1.070.94 at 4 months, 1.141.08 at 12 tive BSCVA).9 months, and 1.201.19 at 24 months for group 2. No A questionnaire10 was used at 4 months; all patients statistically signifi cant differences were noted among were asked to answer subjectively regarding satisfac- values after surgery (ANOVA, P=.6819 and P=.9126, re- tion with visual outcome and vision characteristics. spectively), confi rming the stability of refraction in the postoperative time (Fig 6). STATISTICAL METHODS The deviation of the achieved correction from the Statistically signifi cant differences between the means intended refractive correction was calculated. In group of the data samples were determined by three tests: paired- 1, after 4 months 30 (44.1%) eyes were within 0.5 D sample Student t test, independent-sample Student t test, of the desired refraction, 47 (69.1%) eyes were within and one-way analysis of variance (ANOVA). A probabil- 1.0 D, and 63 (92.6%) eyes were within 2.0 D. In ity value .05 was considered statistically signifi cant. group 2, after 4 months 8 (32%) eyes were within 0.5 D of the desired refraction, 13 (52%) eyes were within 1.0 RESULTS D, and 22 (88%) eyes were within 2.0 D (Fig 7). The mean preoperative astigmatism was 1.250.9 VISUAL ACUITY D in group 1 and 1.580.9 D in group 2; by 2 years Postoperative UCVA of the two groups is shown in postoperatively, mean astigmatism had decreased to Figure 3. Preoperative UCVA was 20/200 in all eyes. 0.750.6 D in group 1 and 1.171.0 D in group 2. In At 4 months, in group 1 (myopia 6.75 to 15.50 D), 17 group 1, mean astigmatism increased at the fi rst postop-

4 journalofrefractivesurgery.com Correction of High Myopia With the Artisan PIOL/Benedetti et al

Figure 3. Postoperative UCVA of eyes in A) 25 group 1 (myopia 6.75 to 15.5 D) and 4 months B) group 2 (myopia 16.0 to 23.0 D). 20 1 year 15 2 years

No. Eyes 10

0 20/20 20/25 20/32 20/40 20/50 20/63 20/100 20/200 <20/200 UCVA A

10 4 months

8 1 year

6 2 years No. Eyes 4

0 20/20 20/25 20/32 20/40 20/50 20/63 20/100 20/200 <20/200 UCVA B erative visit and then decreased later in the postopera- in the fi xation area of one of the haptics (probably due tive period whereas in group 2, the surgical procedure to excessive iris manipulation to enclavate the lens). In did not signifi cantly increase the preoperative astigma- 1 (1.1%) eye, the claw haptic perforated the iris, caus- tism and no irregular astigmatism was induced (Fig 8). ing a slight decentration without subjective discomfort of the patient. A moderate IOL decentration was noted in 5 COMPLICATIONS (5.4%) eyes, and glare/halos were reported by 4 patients Intraoperative problems and postoperative complica- (6 eyes, 6.4%); of these 6 eyes, 5 had 5-mm optic diam- tions are summarized in Tables 3 and 4. In 72% of eyes eter lenses. Two eyes that had moderate preoperative lens (67/93), no intraoperative complications were noted. In opacities did not show any worsening in the postopera- 2 (2.1%) eyes, intraoperative bleeding in the anterior tive period. chamber due to the iridectomy occurred, but resolved Corneal edema, wound leakage, Urrets-Zavalia syn- the day after; in 18 (19.3%) eyes centering or enclava- drome, macular degeneration, or retinal detachment were tion of the PIOL was diffi cult, and iris prolapse occurred not observed. No eye underwent surgical reintervention. in the wound in 5 (5.4%) eyes; in 1 (1.1%) eye, the PIOL was damaged during the lens enclavation. Of the intra- ENDOTHELIAL CELL LOSS operative complications, 62.5% occurred in the fi rst 25 To evaluate the corneal endothelium, we measured operated eyes. The PIOL was not replaced in any case. the cell density. Preoperative mean endothelial cell No serious complications during follow-up were density was 2658360 cells/mm2 and postoperative found. Four (4.3%) eyes developed pigment deposits, mean cell density decreased to 2583361 cells/mm2 probably released from the iris, on the lens surface. at 4 months, 2554322 cells/mm2 at 12 months, and Mean intraocular pressure before surgery was 2514305 cells/mm2 at 24 months. Mean endothelial 14.93.7 mmHg. Elevated intraocular pressure (24 cell density postoperatively was signifi cantly lower mmHg) that needed topical treatment complicated than preoperatively (ANOVA, P=.0276); endothelial the early postoperative course in 7 (7.5%) eyes. At 4 cell loss was 2.8% at 4 months, 3.9% at 12 months, and months after surgery, mean intraocular pressure was 5.4% at 24 months (Fig 9). No signifi cant differences in 13.82.8 mmHg and was 22 mmHg in every eye. endothelial cell loss were noted among the two groups Eleven (11.8%) eyes showed a persistent iris atrophy (t test, P.05).

Journal of Refractive Surgery Volume 21 March/April 2005 5 Correction of High Myopia With the Artisan PIOL/Benedetti et al

Figure 4. Pre- and postoperative BSCVA 60 of eyes in A) group 1 (myopia 6.75 to preoperative 50 15.5 D) and B) group 2 (myopia 16.0 to 23.0 D). 40 4 months

30 1 year No. Eyes 20 2 years

0 20/20 20/25 20/32 20/40 20/50 20/63 20/100 20/200 BSCVA A

15 preoperative 12 4 months 9 1 year

No. Eyes 6 2 years 3

0 20/20 20/25 20/32 20/40 20/50 20/63 20/100 20/200 BSCVA B

Figure 5. Lines gained or lost of BSCVA at 40 4 months. 35 35 Group 1 30 Group 2 25 20

No. Eyes 15 15 11 10 6 7 5 3 4 44 00 001 02 01 0 -2 lines -1 line unchanged +1 line +2 lines +3 lines +4 lines +5 lines +6 lines Lines gained or lost

SUBJECTIVE RESPONSE rection of high refractive errors. Presently, the third- All patients were very satisﬁ ed with the results. In generation PIOL has excellent surface quality and high 95%, patients reported a better quality of life, in most biocompatibility,11,12 which provides a minimal risk of cases it was easier to read (87%), watch TV (89.2%), shop intraocular inﬂ ammation. (80.6%), and play sports (87.1%). Eighty-eight percent re- Posterior chamber PIOLs provide satisfactory refrac- ported a better day drive and 17.2% reported worse night tive results but with the potential problem of cataract driving. In 6.4% (6 of 93 eyes), patients reported halos induction,13 endothelial cell loss,14 problems due to and/or medium intensity nocturnal glare. Of the patients smaller optical zone, and centration.12 included in this study, 96.7% (58/60) would recommend The implantation of an anterior chamber iris support- the surgical procedure to a friend or relative. ed PIOL to correct severe myopia has a long history.1-6,8 It offers more advantages than other refractive techniques, DISCUSSION such as stability, surgical reproducibility, better quality The implantation of PIOLs has been shown to be an vision, accommodation preservation, absence of a clear interesting alternative to corneal surgery for the cor- lens contact, and potential reversibility.

6 journalofrefractivesurgery.com Correction of High Myopia With the Artisan PIOL/Benedetti et al

A B

Figure 6. A) Change over time of spherical equivalent manifest refraction of group 1 (myopia 15.5 D). B) Change over time of spherical equivalent manifest refraction of group 2 (myopia 16.0 to 23.0 D). Error bars indicate standard deviation.

Figure 7. Attempted versus achieved spherical equivalent refraction Figure 8. Changes in mean refractive cylinder power measured in diop- (minus power) of 93 eyes that underwent Artisan PIOL implantation. ters over time. Error bars indicate standard deviation.

Anterior chamber angle-supported PIOLs have more risk of endothelial cell damage,15 can cause pu- TABLE 3 pil ovalization,16-20 iris retraction,19-21 and atrophy17,18 Intraoperative Complications in because of ischemic iridopathy probably induced by 18 93 Eyes (60 Patients) that Underwent haptic compression of the blood vessels of the iris. Iris Claw Phakic Intraocular Lens (IOL) Other complications of angle-supported PIOLs, such as chronic elevation of intraocular pressure,18 cataract Implantation development,18 retinal detachment,18,21-23 halos and Complication No. Eyes (%) glare,18-21 and implant displacement20,21 are described Bleeding 2 (2.1) in the literature. Moreover, sizing is a crucial point for Difficult IOL centering or enclavation 18 (19.3) this type of lens because a lens with a small diameter Iris prolapse 5 (5.4) makes dislocation possible with potential endothelial IOL damage 1 (1.1) cell damage; on the other hand, a wide lens could inter- fere with iris blood circulation causing iris depigmen- tation, iris distortion, and ciliary body inﬂ ammation. Finally, angle-supported PIOLs must be placed on at night. The advantage regarding these lenses is that the geometrical center, not considering the real pupil they are easier to implant. area; this could be a limiting factor in those patients The Artisan lens offers the advantages of anterior with decentered nasal pupil and large pupil diameter chamber IOLs and can be positioned on the pupil cen-

Journal of Refractive Surgery Volume 21 March/April 2005 7 Correction of High Myopia With the Artisan PIOL/Benedetti et al

TABLE 4 Postoperative Complications in 93 Eyes (60 Patients) that Underwent Iris Claw Phakic Intraocular Lens (IOL) Implantation Complication No. Eyes (%) Iris atrophy 11 (11.8) Iris pigment precipitates 4 (4.3) Raised intraocular pressure 4 (4.3) Wound infection 1 (1.1) IOL non centered 5 (5.4) Diplopia 1 (1.1)

Glare/halos 6 (6.4) Figure 9. Mean endothelial cell density over 2 years. Error bars indicate Iris perforation 1 (1.1) standard deviation.

these data are similar to those of Budo et al27 who re- ter. The Artisan lens can be used in young patients ported a safety index of 1.31 in a multicenter study of with anisometric amblyopia with restricted treatment the Artisan PIOL. options.24,25 Our data demonstrate an increase in both UCVA As appears in Figure 1, the mean anterior chamber and BSCVA after Artisan PIOL implantation, and show iris supported PIOL power implanted was 13.63.3 D stability in visual acuity and refractive results 2 years (range: 7.5 to 22.0 D); in 24 (25.8%) eyes, we im- after surgery. planted lenses 11.0 D. In these eyes, laser treatment Concerning the endothelium, our study shows a (photorefractive keratectomy or LASIK) was contra- continual decrease in cell density after lens implanta- indicated because of corneal thickness (attempted re- tion signifi cantly greater than in unoperated eyes, with sidual stromal bed 250 µm), fi nal corneal dioptric an endothelial cell loss of 2.8% at 4 months, 3.9% at 12 power 34 to 35 D, or corneal sublayer abnormalities months, and 5.4% at 24 months. In fact, Bourne et al32 evidenced by confocal microscope examination. reported a mean cell loss of 0.6%0.5% per year over To assess the effectiveness of refractive surgery, 10 years in a longitudinal study in normal unoperated UCVA is the main criterion used.20,26 In our study, at eyes, correlating with the values found in previous 4 months, 19 (20.4%) eyes had UCVA 20/20 and 74 studies33-35 conducted over shorter periods. (79.6%) eyes had UCVA 20/40; 38 (40.9%) eyes had Several studies concerning Artisan iris claw lens im- a refraction within 0.50 D and 60 (64.5%) eyes were plantation reported endothelial damage and cell loss. within 1.00 D, and the refractive results were stable Pèrez-Santonja et al15 reported a signifi cantly greater for 2 years. These data refl ect good predictability, even endothelial cell loss than in cataract surgery36 of 13% if the refractive accuracy was slightly better for lower and 17.6% at 12 and 24 months after surgery, respec- levels of myopia, with 69.1% (group 1) and 52% (group tively. Menezo et al28 reported a mean postoperative 2) within 1.00 D at 4 months. cell loss of 3.85% at 6 months, 6.59% at 12 months, The effi cacy index (0.84 and 0.90 in the two groups, 9.22% at 2 years, 11.68% at 3 years, and 13.42% at 4 respectively, 2 years after surgery) was lower than in years. Landesz et al6 found a mean endothelial cell loss other reports, in which effi cacy index ranges between of 5.3% after 6 months and 8.9% after 12 months. 0.93 and 1.15.27-30 Our results show that the last generation of Artisan In terms of safety, BSCVA remained the same or PIOLs induces a lower mean endothelial cell loss than improved in 100% of eyes; 32.3% (group 1) and 72% previously reported; however, we believe that mean (group 2) of eyes gained 2 lines. This can be ex- endothelial cell loss alone does not refl ect the func- plained by the high optical quality of the lens and by tional damage of corneal endothelium. The coeffi cient the image magnifi cation in the retina due to myopic of variation in cell size, measure of cell size variation intraocular lens,31 especially in group 2, in which the (polymegatism), the percentage of hexagonal cells, and implanted lens had a higher dioptric power. Safety in- measure of cell pleomorphism are values independent dex was 1.12 (group 1) and 1.39 (group 2) at 2 years; of cell density, but offer a more sensitive indication of

8 journalofrefractivesurgery.com Correction of High Myopia With the Artisan PIOL/Benedetti et al

A Figure 10. Iris atrophy in the fixation area due to excessive iris manipulation. endothelial cell damage and functional reserve than cell density alone. Therefore, the corneal endothelium would be evaluated for several years, until endothelium has obtained an equilibrated level after cell loss, to de- termine the stability of endothelial cell density. Evalu- ation of the endothelium should be standardized. Despite the diffi cult surgical procedure, intraoperative complications, such as bleeding, iris prolapse, diffi cult enclavation, or IOL centering, were minimal especially when the surgical technique was improved; in no case was the IOL removed or exchanged. B Many postoperative complications have been de- Figure 11. Lens decentration due to temporal iris perforation at A) 9 scribed after iris claw lens implantation.5,6,27-34,37-45 months postoperatively and B) 15 months postoperatively. Nasal iris Fechner et al39 found no evidence of iris atrophy in atrophy due to excessive iris manipulation is also visible. the fi xation area; on the other hand, Menezo et al30 observed iris atrophy in the fi xation area of one of the haptics in 12.8% of eyes and both haptics in 10.6% of position in 18.7% of eyes; in our study, pigment depo- eyes. In our series, evident iris atrophy was found in sition was found in 4.3% of eyes and was not signifi - 11.8% of eyes in which the surgery was particularly cantly signifi cant. diffi cult and required excessive iris manipulation to Pèrez-Torregrosa et al47 performed a digital system enclavate the lens correctly (Fig 10). measurement of the iris claw decentration and reported Menezo et al30 reported an iris perforation caused by a mean decentration of the IOL from the pupil center of the lens haptic in three (3.2%) eyes, which required rein- 0.470.29 mm; in our study, a clinically insignifi cant tervention in one eye due to lens luxation. Mertens and lens decentration was measured at slit-lamp examina- Tassignon46 described a detachment of iris claw haptic. tion in fi ve (5.9%) eyes. In the present study, iris perforation was observed in one Glare/halos were found in 6.4% (6/93) of eyes; of eye, determining a slight decentration without subjec- these 6 eyes, 5 had 5-mm optic diameter lenses. Budo tive discomfort of the patient and no reintervention (Fig et al27 reported glare in 6% and halos in 8.8% of 249 11). A correct enclavation, with at least 1.5 mm of folded eyes at 3-year follow-up; they exclusively used the Ar- iris inside the claw, is important to avoid this complica- tisan model 206 with a 5.00-mm optic. El Danasoury et tion; moreover a correct surgical technique performed al48 exchanged one 5-mm Artisan lens for a 6-mm lens by expert hands is fundamental to obtain correct lens with a lower power in one patient who reported severe implantation and good centration. night glare, which affected night driving. Pèrez-Santonja et al29 reported corneal pigment de- Pèrez-Santonja et al29 observed infl ammatory reac-

Journal of Refractive Surgery Volume 21 March/April 2005 9 Correction of High Myopia With the Artisan PIOL/Benedetti et al

4. Fechner PU. Iris claw lens [German]. Klin Monatsbl Augenheilkd. tions in 9.3% of eyes; in our study, no eye examination 1987;191:26-29. by slit-lamp biomicroscopy revealed evident fl are in 5. Fechner PU, Worst JFG. A new concave intraocular lens for the the anterior chamber. In another study, the same au- correction of high myopia. Eur J Implant Ref Surg. 1989;1:41-43. 49 thors described increased fl are using cell fl are pho- 6. Landesz M, Worst JG, Siertsema JV, van Rij G. Correction of tometry in both angle-supported and iris-claw PIOLs in high myopia with the Worst myopia claw intraocular lens. eyes without clinically infl ammatory reactions. J Refract Surg. 1995;11:16-25. Menezo et al28,30 and Fechner et al39 did not describe 7. Van der Heijde GL. Some optical aspects of implantation of an IOL lens opacities after iris-claw implantation. Budo et al27 in a myopic eye. Eur J Implant Refract Surg. 1989;1:245-248. found age-related cataract in 2.4% of eyes and Pèrez- 8. Van der Heijde GL, Fechner PU, Worst JG. Optical consequenc- es of implantation of a negative intraocular lens in myopic pa- 29 Santonja et al reported cataract development in 3%. tients. Klin Monatsbl Augenheilkd. 1988;193:99-102. 50 Maloney et al described the development of nonpro- 9. Koch DD, Kohnen T, Obstbaum SA, Rosen ES. Format for report- gressive lens opacities in 3.1% as a result of surgical ing refractive surgical data. J Cataract Refract Surg. 1998;24:285- trauma. In our study, no eyes developed lens opacities. 287. The two eyes that had a moderate preoperative lens opac- 10. McGhee CN, Orr D, Kidd B, Stark C, Bryce IG, Anastas CN. Psy- chological aspects of excimer laser surgery for myopia: reasons ity did not show any progression in the postoperative pe- for seeking treatment and patient satisfaction. Br J Ophthalmol. riod, and we are following their possible evolution. 1996;80:874-879. Other complications reported in the literature such as 11. Kohnen T, Baumeister M, Magdowski G. Scanning electron corneal edema,27,34 iridocyclitis,28,29,39 wound leakage,28 microscopic characteristics of phakic intraocular lenses. cystic wounds,29,34 Urrets-Zavalia syndrome,28,37,39 reti- Ophthalmology. 2000;107:934-939. nal detachment,27,39 ischemic optic neuropathy,26 vitre- 12. Assetto V, Benedetti S, Pesando P. Collamer intraocular con- 51 52 tact lens to correct high myopia. J Cataract Refract Surg. ous hemorrhage, and choroidal neovascularization 1996;22:551-556. were not found in our study. 13. Rosen E, Gore C. Staar collamer posterior chamber phakic intra- Recently, PIOL implantation has been considered a ocular lens to correct myopia and hyperopia. J Cataract Refract satisfactory surgical procedure to correct high myopia. Surg. 1998;24:596-606. Some potential advantages include optical improve- 14. Dejaco-Ruhswurm I, Scholz U, Pieh S, Hanselmayer G, Lackner ment, preservation of accommodation, and potential B, Italon C, Ploner M, Skorpik C. Long-term endothelial changes in phakic eyes with posterior chamber intraocular lenses. reversibility; some disadvantages that could limit their J Cataract Refract Surg. 2002;28:1589-1593. use include long-term complications to the corneal en- 15. Pèrez-Santonja JJ, Iradier MT, Sanz-Iglesias L, Serrano JM, Zato dothelium and anterior chamber structures especially MA. Endothelial changes in phakic eyes with anterior cham- for angle-supported lenses or possible cataract devel- ber intraocular lenses to correct high myopia. J Cataract Refract Surg. 1996;22:1017-1022. opment for posterior chamber IOLs. 16. Baikoff G. ZB5M Multicenter Study. Phakic Lens Product Mono- Our results with Artisan PIOL implantation to cor- graph. Claremont, Calif: Chiron Vision Corporation; 1997. rect high myopia show an increase in both UCVA and 17. de Souza RF, Forseto A, Nosè R. Anterior chamber intraocular BSCVA and demonstrate stability in visual acuity and lens for high myopia: fi ve year results. J Cataract Refract Surg. refractive results 2 years after surgery. 2001;27:1248-1253. Although it is a diffi cult surgical procedure, our ex- 18. Aliò JL, de la Hoz F, Pèrez-Santonja JJ, Ruiz-Moreno JM, Que- perience over 2 years demonstrated minimal intraoper- sada JA. Phakic anterior chamber lenses for the correction of myopia: a 7-year cumulative analysis of complications in 263 ative and postoperative complications. When the proce- cases. Ophthalmology. 1999;106:458-466. dure is performed correctly by an experienced surgeon, 19. Allemann N, Chamon W, Tanaka HM, Mori ES, Campos M, it represents a safe and repeatable surgical technique. Schor P, Baikoff G. Myopic angle-supported intraocular lenses; As previously commented on by other authors,27,37 fur- two-year follow-up. Ophthalmology. 2000;107:1549-1554. ther follow-up is necessary to confi rm these data and to 20. Pèrez-Santonja JJ, Aliò JL, Jimènez-Alfaro I, Zato MA. Surgical monitor potential long-term complications. correction of severe myopia with an angle-supported phakic intraocular lens. J Cataract Refract Surg. 2000;26:1288-1302. 21. Baikoff G, Arne JL, Bokobza Y, Colin J, George JL, Lagoutte F, REFERENCES Lesure P, Montard M, Saragoussi JJ, Secheyron P. Angle-fi xated 1. Strampelli B. Anterior chamber lens. Arch Ophthalmol. anterior chamber phakic intraocular lens for myopia of -7 to -19 1954;66:12-17. diopters. J Refract Surg. 1998;14:282-293. 2. Strampelli B. Tolerance of acrylic lenses in the anterior chamber 22. Ruiz-Moreno JM, Alio JL, Perez-Santonja JJ, de la Hoz F. 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anterior chamber lenses. Am J Ophthalmol. 1993;115:145-148. 39. Fechner PU, Strobel J, Wichmann W. Correction of myopia by 24. Saxena R, van Minderhout HM, Luyten GP. Anterior chamber implantation of a concave Worst-iris claw lens into phakic eyes. iris-fi xated phakic intraocular lens for anisometropic amblyo- Refract Corneal Surg. 1991;7:286-298. pia. J Cataract Refract Surg. 2003;29:835-838. 40. Fechner PU, Haubitz I, Wichmann W, Wulff K. Worst-Fechner 25. Chipont EM, Garcìa-Hermosa P, Alio JL. Reversal of myopic an- biconcave minus power phakic iris-claw lens. J Refract Surg. isometropic amblyopia with phakic intraocular lens implanta- 1999;15:93-105. tion. J Refract Surg. 2001;17:460-462. 41. Guell JL, Vazquez M, Gris O, De Muller A, Manero F. Combined 26. Pèrez-Santonja JJ, Bueno JL, Meza J, Garcia-Sandoval B, Serrano surgery to correct high myopia: iris claw phakic intraocular lens JM, Zato MA. Ischemic optic neuropathy after intraocular lens and laser in situ keratomileusis. 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