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Clinical results of AcrySof intraocular lens implantation
Clinical results of AcrySof intraocular lens implantation Encarna Mengual, MD, Juan Garda, MD, Juan Carlos Elvira, MD, Jose Ramon Hueso, MD
T
he use of flexible intraocular lenses (IOLs) in small incision cataract surgery is increasing as these lenses retain the advantages of modern cataract surgery such as less trauma, earlier recovery, and faster surgery. 1 Surgeons performing small incision cataract surgery may choose among a range of flexible lenses made of one or two-piece silicone, hydrogel, or acrylic materials. 2 For the past decade, silicone lenses have been the most frequently implanted. 3 The AcrySof IOL contains the same methacrylate polymer used in rigid poly(methyl methacrylate) (PMMA) IOLs (Figure O. This lens offers flexibility as it may be implanted in the bag or ciliary sulcus (Figure 2).
From the San Juan University Hospital, Alicante, Spain. Reprint requests to Encarna Mengual, MD, Avenida Costablanca, 80, Urbanization Porto Principe, Bloque 2, 2nd Floor, Playa de San Juan, Alicante, Spain. 114
We present the clinical results of implanting 100 AcrySof 10Ls including the functional results and the intraocular performance of the lenses.
Patients and Methods The AcrySof (model MA60BM) is a soft, posterior chamber acrylic lens consisting of three pieces. The optic is of a foldable acrylic material, more precisely acrylate copolymer. This biconvex lens has a 6.0 diameter and is 0.82 mm thick; its refractive index is 1.55. The PMMA haptics are a modified C-shape with an angulation of 10 degrees and a length of 13.0 mm. This retrospective study evaluated 100 patients (39 men, 61 women) with a mean age of 67 years, ranging from 58 to 84 years with the exception of a 5-year-old with traumatic cataract. All patients with cataract were included in the study, regardless of whether they suffered related eye pathology. Mean follow-up was 9 months.
J CATARACT REFRACT SURG-VOL 24, JANUARY 1998
CLINICAL RESULTS OF ACRYSOF IMPLANTATION \
AcrySof·
a
--T 10"
Metilo
•
-.14
Feniletilo
Figure 1. (Mengual) Composition of the AcrySof IOL.
Figure 2.
Of the 100 patients, 81 presented preoperatively without eye pathology and 19, with eye pathology. In the group with eye pathology, 7 had diabetes (1 with previous vitrectomy), 1 had traumatic cataract, 1 had central corneal leukoma, 6 had pseudoexfoliation syndrome, and 4 had glaucoma (2 with optic disc cupping greater than 0.7; 2 with laser iridectomy). For surgery, peribulbar or retrobulbar anesthesia was used, depending on patient characteristics and surgeon preference. Patients had surgery by one of four surgeons (Appendix). In all cases, phacoemulsification was used (scleral incision in 47 cases; corneal incision in 53 cases). In 4 cases, combined phacoemulsification and trabeculectomy was performed. Phacoemulsification technique (chip and flip, divide and conquer, phaco chop, or stop and chop) depended on type of cataract (mild, medium hard, or hard) and surgeon preference. The IOLs were implanted with straight pincers or with Western Medical forceps. The incision was closed with a 10-0 or 9-0 0 nylon suture depending on the type of incision. Postoperative examinations included best corrected visual acuity (BCVA); uncorrected visual acuity (UCVA); evaluation for diabetes, pseudoexfoliation, anterior synechias, corneal edema, and anterior and posterior capsule fibrosis; IOL power; type of incision; capsulorhexis size; Tyndall evaluation; intraocular pressure measurement; whether and when the patient had a neodymium:YAG (Nd:YAG) laser capsulotomy; IOL centration; and complications. In addition, endothelial
cell count was done by specular microscopy and statistically evaluated using SPSS software; whether the patient had preoperative eye pathology was not considered in this statistical analysis.
(Mengual) Dimensions of the AcrySof IOL.
Results The most common intraoperative complication was capsular rupture (seven anterior, six posterior). Of the posterior capsule ruptures, four occurred during emulsification of the crystalline lens and two during IOL implantation. In five eyes with anterior capsule rupture, the IOL could be placed in the bag; the other eye, which had traumatic cataract, required sulcus implantation. When posterior capsule rupture occurred during phacoemulsification, the lens was implanted in the sulcus and when it occurred during implantation, in the bag. Postoperative complications are shown in Table 1. The difference between the mean preoperative and mean 1 and 3 month postoperative endothelial cell
Table 1. Postoperative complications.
Marked anterior capsular fibrosis (ring> 1.0 mm)
6
IOL displacement, vertical axis not affected
2
Posterior capsule opacity requiring Nd:YAG capsulotomy Iris-IOL synechias
J CATARACT REFRACT SURG-VOL 24, JANUARY 1998
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CLINICAL RESULTS OF ACRYSOF IMPLANTATION
Table 2.
Best corrected visual acuity 9 months postoperatively.
> 20/40
2
20/20
0
(1152)
81 18
(22.22)
(5.26)
31
(38.21)
28
(34.56)
(5 .26)
4
(4.93)
7
(36.84)
0
8
(42.10)
0
20/100
(5.26)
0
20/200
(5.26)
0
20/25 20/30
0
20/40 20/50 20/60
(100.00)
counts was statistically significant (P < .001). The difference between the 1 and 3 month counts was not statistically significant. Table 2 shows the BCVA 9 months postoperatively; BCVA and UCVA were 20/40 or better in 11.52% of patients with preoperative pathology and 100% of those without pathology.
Discussion We did not observe any adverse reaction related to the AcrySofIOL in our series; we believe this is because of the lens' excellent biocompatibility. We observed no lens discoloration, significant postoperative anterior chamber inflammation, or capsule contraction. Other studies have found that anterior chamber fibrinoid reaction with silicone IOLs occurs 2.5% more than with AcrySof lenses (T. Oshika, MD, "La Transparencia de la Capsula, una de la Ventajas de la Nueva Lente," Phaco and Foldables, July 1994, page 6). Unlike silicone lenses, the AcrySof IOL has angulated haptics. Thus, it can be implanted in the bag or sulcus. In addition, its optic size leads to good lens centration. After 9 months, only 1 case of posterior capsule fibrosis requiring Nd:YAG capsulotomy occurred in our series. In a study by D.J. Spalton, FRCS, FRCOphth ("Estudio Comparativo de la Superficie de las Lentes Acrflicas, PMMA y Silicona," Phaco and Foldables, October 1995, page 4), photography and picture analy116
sis showed posterior capsules with AcrySof IOLs to be transparent, indicating that the lenses are stable, which blocks cells from entering the capsule and proliferating. Another study found that 2 years after AcrySof IOL implantation, the rate ofNd:YAG laser capsulotomy for posterior capsule fibrosis was 9.3% (D. Koch, MD, "Comportamiento de AcrySof con Laser YAG," Phaco and Foldables, October 1995, page 8). The study also found that the AcrySof IOL caused significantly less severe fibrosis than silicone and PMMA lenses. Regarding the glistenings that have been attributed to AcrySof IOLs, such phenomena are not exclusive to these lenses. Researchers, including D. Apple, MD, and coauthors (''Advances in IOL Materials and Techniques Create New Options," Ocular Surgery News, September 1995, pages 15-23), have concluded that glistenings can also appear with PMMA and silicone lenses and that these phenomena have no assessable subjective clinical effect. Another potential complication of AcrySof IOLs is cracking during insertion. This is noticed through a dilated pupil in the immediate postoperative period rather than during surgery4 (Figure 3). The cracking may result from how the lens is folded, the instrument used for insertion (e.g., Fine universal forceps), or when during surgery it is implanted. As with glistenings, the cracking does not seem to have an assessable subjective clinical effect. We conclude that the clinical results thus far indicate that AcrySof is safe and effective in small incision cataract surgery.
Figure 3. (Mengual) A cracked AcrySof IOL is seen in the immediate postoperative period.
J CATARACf REFRACT SURG-VOL 24. JANUARY 1998
CLINICAL RESULTS OF ACRYSOF IMPLANTATION
References 1. Martin RG, Sanders DR, Van der Karr MA, DeLuca M. Effect of small incision intraocular lens surgery on postoperative inflammation and astigmatism; a study of the AMO SI-18NB small incision lens. J Cataract Refract Surg 1992; 18:51-57 2. Oshika T, Suzuki Y, Kizaki H, Yaguchi S. Two year clinical study of a soft acrylic intraocular lens. J Cataract Refract Surg 1996; 22:104-109 3. Menapace R, Radax U, Vass C, et al. In the bag implantation of the PhacoFlex SI-30 high-refractive silicone lens through self-sealing sclerocorneal and clear
corneal incisions. Eur J Implant Refract Surg 1994; 6:143-152 4. Carlson KH, Johnson OW Cracking of acrylic intraocular lenses during capsular bag insertion. Ophthalmic Surg Lasers 1995; 26:572-573
Appendix Four surgeons took part in this study: Jose Ramon Hueso, MD, Jose Juan Martinez, MD, Juan Carlos Elvira, MD, and Encarna Mengual, MD.
J CATARACT REFRACT SURG-VOL 24, JANUARY 1998
117.
T
he use of flexible intraocular lenses (IOLs) in small incision cataract surgery is increasing as these lenses retain the advantages of modern cataract surgery such as less trauma, earlier recovery, and faster surgery. 1 Surgeons performing small incision cataract surgery may choose among a range of flexible lenses made of one or two-piece silicone, hydrogel, or acrylic materials. 2 For the past decade, silicone lenses have been the most frequently implanted. 3 The AcrySof IOL contains the same methacrylate polymer used in rigid poly(methyl methacrylate) (PMMA) IOLs (Figure O. This lens offers flexibility as it may be implanted in the bag or ciliary sulcus (Figure 2).
From the San Juan University Hospital, Alicante, Spain. Reprint requests to Encarna Mengual, MD, Avenida Costablanca, 80, Urbanization Porto Principe, Bloque 2, 2nd Floor, Playa de San Juan, Alicante, Spain. 114
We present the clinical results of implanting 100 AcrySof 10Ls including the functional results and the intraocular performance of the lenses.
Patients and Methods The AcrySof (model MA60BM) is a soft, posterior chamber acrylic lens consisting of three pieces. The optic is of a foldable acrylic material, more precisely acrylate copolymer. This biconvex lens has a 6.0 diameter and is 0.82 mm thick; its refractive index is 1.55. The PMMA haptics are a modified C-shape with an angulation of 10 degrees and a length of 13.0 mm. This retrospective study evaluated 100 patients (39 men, 61 women) with a mean age of 67 years, ranging from 58 to 84 years with the exception of a 5-year-old with traumatic cataract. All patients with cataract were included in the study, regardless of whether they suffered related eye pathology. Mean follow-up was 9 months.
J CATARACT REFRACT SURG-VOL 24, JANUARY 1998
CLINICAL RESULTS OF ACRYSOF IMPLANTATION \
AcrySof·
a
--T 10"
Metilo
•
-.14
Feniletilo
Figure 1. (Mengual) Composition of the AcrySof IOL.
Figure 2.
Of the 100 patients, 81 presented preoperatively without eye pathology and 19, with eye pathology. In the group with eye pathology, 7 had diabetes (1 with previous vitrectomy), 1 had traumatic cataract, 1 had central corneal leukoma, 6 had pseudoexfoliation syndrome, and 4 had glaucoma (2 with optic disc cupping greater than 0.7; 2 with laser iridectomy). For surgery, peribulbar or retrobulbar anesthesia was used, depending on patient characteristics and surgeon preference. Patients had surgery by one of four surgeons (Appendix). In all cases, phacoemulsification was used (scleral incision in 47 cases; corneal incision in 53 cases). In 4 cases, combined phacoemulsification and trabeculectomy was performed. Phacoemulsification technique (chip and flip, divide and conquer, phaco chop, or stop and chop) depended on type of cataract (mild, medium hard, or hard) and surgeon preference. The IOLs were implanted with straight pincers or with Western Medical forceps. The incision was closed with a 10-0 or 9-0 0 nylon suture depending on the type of incision. Postoperative examinations included best corrected visual acuity (BCVA); uncorrected visual acuity (UCVA); evaluation for diabetes, pseudoexfoliation, anterior synechias, corneal edema, and anterior and posterior capsule fibrosis; IOL power; type of incision; capsulorhexis size; Tyndall evaluation; intraocular pressure measurement; whether and when the patient had a neodymium:YAG (Nd:YAG) laser capsulotomy; IOL centration; and complications. In addition, endothelial
cell count was done by specular microscopy and statistically evaluated using SPSS software; whether the patient had preoperative eye pathology was not considered in this statistical analysis.
(Mengual) Dimensions of the AcrySof IOL.
Results The most common intraoperative complication was capsular rupture (seven anterior, six posterior). Of the posterior capsule ruptures, four occurred during emulsification of the crystalline lens and two during IOL implantation. In five eyes with anterior capsule rupture, the IOL could be placed in the bag; the other eye, which had traumatic cataract, required sulcus implantation. When posterior capsule rupture occurred during phacoemulsification, the lens was implanted in the sulcus and when it occurred during implantation, in the bag. Postoperative complications are shown in Table 1. The difference between the mean preoperative and mean 1 and 3 month postoperative endothelial cell
Table 1. Postoperative complications.
Marked anterior capsular fibrosis (ring> 1.0 mm)
6
IOL displacement, vertical axis not affected
2
Posterior capsule opacity requiring Nd:YAG capsulotomy Iris-IOL synechias
J CATARACT REFRACT SURG-VOL 24, JANUARY 1998
115
CLINICAL RESULTS OF ACRYSOF IMPLANTATION
Table 2.
Best corrected visual acuity 9 months postoperatively.
> 20/40
2
20/20
0
(1152)
81 18
(22.22)
(5.26)
31
(38.21)
28
(34.56)
(5 .26)
4
(4.93)
7
(36.84)
0
8
(42.10)
0
20/100
(5.26)
0
20/200
(5.26)
0
20/25 20/30
0
20/40 20/50 20/60
(100.00)
counts was statistically significant (P < .001). The difference between the 1 and 3 month counts was not statistically significant. Table 2 shows the BCVA 9 months postoperatively; BCVA and UCVA were 20/40 or better in 11.52% of patients with preoperative pathology and 100% of those without pathology.
Discussion We did not observe any adverse reaction related to the AcrySofIOL in our series; we believe this is because of the lens' excellent biocompatibility. We observed no lens discoloration, significant postoperative anterior chamber inflammation, or capsule contraction. Other studies have found that anterior chamber fibrinoid reaction with silicone IOLs occurs 2.5% more than with AcrySof lenses (T. Oshika, MD, "La Transparencia de la Capsula, una de la Ventajas de la Nueva Lente," Phaco and Foldables, July 1994, page 6). Unlike silicone lenses, the AcrySof IOL has angulated haptics. Thus, it can be implanted in the bag or sulcus. In addition, its optic size leads to good lens centration. After 9 months, only 1 case of posterior capsule fibrosis requiring Nd:YAG capsulotomy occurred in our series. In a study by D.J. Spalton, FRCS, FRCOphth ("Estudio Comparativo de la Superficie de las Lentes Acrflicas, PMMA y Silicona," Phaco and Foldables, October 1995, page 4), photography and picture analy116
sis showed posterior capsules with AcrySof IOLs to be transparent, indicating that the lenses are stable, which blocks cells from entering the capsule and proliferating. Another study found that 2 years after AcrySof IOL implantation, the rate ofNd:YAG laser capsulotomy for posterior capsule fibrosis was 9.3% (D. Koch, MD, "Comportamiento de AcrySof con Laser YAG," Phaco and Foldables, October 1995, page 8). The study also found that the AcrySof IOL caused significantly less severe fibrosis than silicone and PMMA lenses. Regarding the glistenings that have been attributed to AcrySof IOLs, such phenomena are not exclusive to these lenses. Researchers, including D. Apple, MD, and coauthors (''Advances in IOL Materials and Techniques Create New Options," Ocular Surgery News, September 1995, pages 15-23), have concluded that glistenings can also appear with PMMA and silicone lenses and that these phenomena have no assessable subjective clinical effect. Another potential complication of AcrySof IOLs is cracking during insertion. This is noticed through a dilated pupil in the immediate postoperative period rather than during surgery4 (Figure 3). The cracking may result from how the lens is folded, the instrument used for insertion (e.g., Fine universal forceps), or when during surgery it is implanted. As with glistenings, the cracking does not seem to have an assessable subjective clinical effect. We conclude that the clinical results thus far indicate that AcrySof is safe and effective in small incision cataract surgery.
Figure 3. (Mengual) A cracked AcrySof IOL is seen in the immediate postoperative period.
J CATARACf REFRACT SURG-VOL 24. JANUARY 1998
CLINICAL RESULTS OF ACRYSOF IMPLANTATION
References 1. Martin RG, Sanders DR, Van der Karr MA, DeLuca M. Effect of small incision intraocular lens surgery on postoperative inflammation and astigmatism; a study of the AMO SI-18NB small incision lens. J Cataract Refract Surg 1992; 18:51-57 2. Oshika T, Suzuki Y, Kizaki H, Yaguchi S. Two year clinical study of a soft acrylic intraocular lens. J Cataract Refract Surg 1996; 22:104-109 3. Menapace R, Radax U, Vass C, et al. In the bag implantation of the PhacoFlex SI-30 high-refractive silicone lens through self-sealing sclerocorneal and clear
corneal incisions. Eur J Implant Refract Surg 1994; 6:143-152 4. Carlson KH, Johnson OW Cracking of acrylic intraocular lenses during capsular bag insertion. Ophthalmic Surg Lasers 1995; 26:572-573
Appendix Four surgeons took part in this study: Jose Ramon Hueso, MD, Jose Juan Martinez, MD, Juan Carlos Elvira, MD, and Encarna Mengual, MD.
J CATARACT REFRACT SURG-VOL 24, JANUARY 1998
117.