Tecnis Z9000 Intraocular Lens Research Articles

Comparative study of aspheric intraocular lenses with negative spherical aberration or no aberration

To compare the quality of vision with an aspheric intraocular lens (IOL) with no aberration and an IOL with negative spherical aberration. Bretonneau University Hospital, Tours, France. Patients scheduled for cataract surgery were randomly chosen to bilaterally receive a SofPort Advanced Optics IOL with no aberration (no-aberration IOL group) or a Tecnis Z9000 IOL with negative spherical aberration (negative-aberration IOL group). Six-month postoperative outcomes included patient-centered visual disability assessed with the Activities of Daily Vision Scale (ADVS), contrast sensitivity testing, and wavefront aberration analysis. There was no difference in the overall ADVS score between the 2 groups (P = 0.07); however, the negative-aberration IOL group had a better night-driving score (mean 82.7 +/- 15.1 [SD] versus 66.4 +/- 7.6) (P<.001) and the no-aberration IOL group had a better corrected near-vision score (mean 96.5 +/- 6.2 versus 86.2 +/- 13.2) (P<.001). Mesopic contrast sensitivity was significantly better in the negative-aberration IOL group at intermediate and high frequencies; the no-aberration IOL group performed better under photopic conditions at intermediate frequencies. There was significantly higher spherical aberration (mean 0.11 +/- 0.05 microm versus 0.01 +/- 0.06 microm; P = .001) and lower 3rd-order coma (mean 0.09 +/- 0.06 microm versus 0.15 +/- 0.06 microm; P<.001) in the no-aberration IOL group than in the negative-aberration IOL group, which had better MTF. Bilateral implantation of an IOL with no aberration resulted in better quality of near vision. A negative spherical aberration IOL provided better night-driving vision and improvements in mesopic contrast sensitivity and MTF.

Binocular implantation of the Tecnis Z9000 or AcrySof MA60AC intraocular lens in routine cataract surgery: Prospective randomized controlled trial comparing VF-14 scores

To compare vision-related quality of life after binocular implantation of the Tecnis Z9000 intraocular lens (IOL) (Advanced Medical Optics) or the AcrySof MA60AC IOL (Alcon). Moorfields Eye Hospital, London, United Kingdom. The study was a double-masked prospective randomized controlled trial. The main outcome measure was the percentage of patients achieving a Visual Function-14 (VF-14) score of 90 or higher. Additional outcome measures were dysphotopsia symptom scores, a 5-point subjective grading of overall satisfaction, refraction, photopic and mesopic best corrected visual acuities, uncorrected visual acuity, Pelli-Robson contrast sensitivity, aberrometry, infrared pupillometry, and evaluation of posterior capsule opacification scores. Seventy-nine patients who had bilateral implantation of the Z9000 IOL and 100 patients who had bilateral implantation of the MA60AC IOL were assessed a mean of 7.9 months +/- 2.9 (SD) (range 4 to 16 months) after second-eye surgery. Spherical aberration (mean: Z9000, 0.00 microm +/- 0.06 [SD]; MA60AC, +0.14 +/- 0.09 microm) and root mean square scores for higher-order aberrations combined (mean: Z9000, 0.26 +/- 0.11 microm; MA60AC, 0.32 +/- 0.14 microm) were significantly lower in patients with the Z9000 IOL (P<.001 and P = .007, respectively). The VF-14 scores were 90 or higher in 96.2% of Z9000 patients and 90.0% of MA60AC patients (P = .15). It is unlikely that this weak trend in favor of the Z9000 IOL was clinically significant. The VF-14 scores were heavily skewed toward a perfect outcome and similarly distributed in both groups (median 100; interquartile range 98 to 100). Results for all other outcomes, including measures of acuity, were similarly distributed in Z9000 patients and MA60AC patients. The Z9000 IOL reduced spherical aberration compared with the MA60AC IOL. No improvement in subjective visual function using the VF-14 questionnaire was detected.

Quality of vision after cataract surgery after Tecnis Z9000 intraocular lens implantation: Effect of contrast sensitivity and wavefront aberration improvements on the quality of daily vision

To compare ocular performance and quality of vision in pseudophakic eyes with an aspherical intraocular lens (IOL) or a conventional spherical IOL. Bretonneau University Hospital, Tours, France. Twenty patients (40 eyes) were randomly divided in 2 equal groups to bilaterally receive the aspherical Tecnis Z9000 IOL (AMO) or the spherical CeeOn Edge 911 IOL (AMO). Contrast sensitivity was measured and ocular wavefront analysis performed before surgery and 6 months after. Patients completed the Activities of Daily Vision Scale (ADVS) to evaluate patient-centered visual outcomes. Other examinations included refraction before and after mydriasis and pupil diameter. The mean postoperative best corrected visual acuity (logMAR) was 0.03 +/- 0.05 (SD) in the Tecnis group and 0.01 +/- 0.05 in the CeeOn Edge group (P = .41). Refractive evaluation with mydriasis showed a mean myopic shift as low as -0.02 +/- 0.36 diopter (D) in the Tecnis group and -0.51 +/- 0.37 D in the CeeOn Edge group (P = .001). Mesopic contrast sensitivity at high spatial frequencies was significantly better in the Tecnis group (P<.001), while contrast sensitivity under photopic and glare conditions was not different between the 2 groups. Spherical aberration was significantly lower in the Tecnis group, which had a mean Z(4)(0) of 0.01 +/- 0.06 microm, than in the CeeOn Edge group, which had a mean Z(4)(0) of 0.16 +/- 0.12 microm (P<.001). The global score on the ADVS was not statistically different between groups; however, quality of distance vision was better in the Tecnis group than in the CeeOn Edge group (mean 99.0 +/- 2.0 versus 89.2 +/- 3.4) (P<.001). Implantation of an aspherical IOL with a negative spherical aberration resulted in reduced ocular spherical aberration and improved mesopic contrast sensitivity and led to better subjective quality of vision.

Spherical aberration and coma with an aspherical and a spherical intraocular lens in normal age-matched eyes

To study optical aberrations in eyes having uneventful cataract surgery and in-the-bag implantation of an aspherical Tecnis Z9000 intraocular lens (IOL) (AMO) or a spherical CeeOn Edge 911 IOL (Pharmacia) and compare the results with those in a group of phakic age-matched eyes. Ophthalmic Unit, Hospital and University of Verona, Verona, Italy. Three groups, each with 30 patients (30 eyes), were examined with the Topcon KR-9000PW topographer/aberrometer. Spherical aberration and coma were analyzed in detail for 4.0 mm optical zone. Internal values were obtained by subtracting corneal aberrations from ocular aberrations. Point spread function and modulation transfer function (MTF) were considered for optical quality. The mean internal spherical aberration Z(4)(0) was -0.048 microm +/- 0.017 (SD) in the Tecnis group, +0.033 +/- 0.026 microm in the 911 Edge group (P<.001), and -0.013 +/- 0.056 microm in the phakic group (P = .149). The mean internal vertical coma Z(3)(-1) was 0.087 +/- 0.056 microm, 0.054 +/- 0.043 microm (P = .005), and 0.044 +/- 0.044 microm (P<.001), respectively. The internal horizontal coma Z(3)(+1) showed a similar pattern; however, total resulting coma was similar in the 3 groups. The mean Strehl ratio was 0.284 +/- 0.166 in the Tecnis group, 0.145 +/- 0.077 in the 911 Edge group (P<.01), and 0.164 +/- 0.097 in the phakic group (P<.01). The MTF curve was better in the Tecnis group (P<.001). After uneventful implantation, the aspherical IOL yielded better ocular aberration and optical quality results than the spherical IOL. Induced coma was somewhat higher in the Tecnis group; however, the overall results were not affected. Physiologic IOL decentration after correct in-the-bag implantation did not negate the advantages of asphericity.

Spherical aberration and contrast sensitivity after cataract surgery with the Tecnis Z9000 intraocular lens

To determine whether implantation of an intraocular lens (IOL) with a modified prolate anterior surface (Tecnis Z9000, AMO) results in reduced spherical aberration and improved contrast sensitivity after cataract surgery. Hospital NISA Virgen del Consuelo, Valencia, Spain. In an intraindividual randomized prospective study of 30 patients with bilateral cataract, the Tecnis Z9000 IOL was compared with 2 IOLs with spherical surfaces, the AR40e (AMO) and the Stabibag (Ioltech). Ocular aberrations for a 4.0 mm pupil and 6.0 mm pupil were measured with a Hartmann-Shack aberrometer. Quality of vision was measured by visual acuity and contrast sensitivity under mesopic and photopic conditions. Eyes with the Tecnis Z9000 IOL had significantly less spherical aberration and a greater Strehl ratio after surgery. Significant reduction in coma aberration was also found in some cases. Refraction, visual acuity, and contrast sensitivity were not significantly different between the 3 IOL groups. A significant reduction in spherical aberration after Tecnis Z9000 IOL implantation was achieved, but visual acuity and contrast sensitivity were not affected by the aspheric silicone IOL compared to spherical acrylic IOLs.

Negative dysphotopsia associated with implantation of the Z9000 intraocular lens

Uneventful small-incision cataract surgery was performed in a 70-year-old man and a 62-year-old woman with implantation of a Tecnis Z9000 intraocular lens (IOL) (Pharmacia). No ocular pathology was present in the patients preoperatively. Unsolicited complaints of negative dysphotopsia were made postoperatively, and the symptoms have persisted for more than 1 year in both patients. Symptomatic negative dysphotopsia may be seen in association with the Z9000 IOL.

Optical performance of 3 intraocular lens designs in the presence of decentration

To study the theoretical optical performance of 3 intraocular lens (IOL) designs in the presence of IOL decentration. Optics Center, Bausch & Lomb, Rochester, New York, USA. A ray-tracing program was used to evaluate the effect of IOL decentration on the optical performance of 3 silicone IOLs (LI61U, Bausch & Lomb; Tecnis Z9000, Advanced Medical Optics; and a new aberration-free IOL [SofPort AO, Bausch & Lomb]) in an experimental model eye. The study was done using pupil diameters of 3.0 mm, 4.0 mm, and 5.0 mm and IOL decentrations of 0 mm, 0.25 mm, 0.50 mm, 0.75 mm, and 1.00 mm. The modulation transfer functions were computed and plotted. A Monte Carlo simulation analysis with 1000 trials with IOL decentration randomly varying for each pupil size was performed. Decentration of LI61U and Tecnis Z9000 IOLs led to asymmetrical higher-order aberrations that adversely affected the optical performance of the model eye; performance was not affected with the aberration-free IOL because it lacks inherent spherical aberration. Optical performance with the aberration-free IOL was better than with the LI61U IOL as the former has less spherical aberration and did not introduce other aberrations when decentered. Performance with the aberration-free IOL was better than with the Tecnis Z9000 IOL for 3.0 mm, 4.0 mm, and 5.0 mm pupils when decentration exceeded 0.15 mm, 0.30 mm, and 0.38 mm, respectively. Performance with the LI61U IOL was better than with the Tecnis Z9000 IOL for 3.0 mm, 4.0 mm, and 5.0 mm pupils when decentration exceeded 0.3 mm, 0.5 mm, and 0.5 mm, respectively. Monte Carlo simulations showed the expected postoperative results of the LI61U IOL and aberration-free IOL would be repeatable and predictable, whereas the outcomes with the Tecnis Z9000 IOL would vary widely. The optical performance of the model eye was not affected by decentration of an aspheric IOL designed to have no inherent spherical aberration. With decentration, the performance with the new IOL was better than with a conventional spherical IOL and an aspheric IOL designed to offset the spherical aberration of an average cornea.

Influencia de la aberración esférica en la función visual tras cirugía de catarata: ensayo prospectivo aleatorio

We compare the contrast sensitivity and visual acuity obtained with an anterior surface modified prolate intraocular lens (Tecnis Z9000) with the contrast sensitivity and visual acuity obtained with a standard acrylic foldable intraocular lens (Acrysof SA60 AT). In this prospective trial, 64 patients presenting for cataract surgery were randomized to receive in both eyes either the Tecnis Z9000 intraocular lens or the the Acrysof SA60AT intraocular lens: 32 Tecnis Z9000 and 32 Acrysof SA60AT. Visual acuity and contrast sensitivity were monocular and binocularly tested in all of them preoperatively and three months after surgery. The Tecnis Z9000 intraocular lens provided statistically significantly better monocular (Tecnis group: 0.85; Acrysof group: 0.78; p < 0.01) and binocular (Tecnis group: 0.95; Acrysof group: 0.86; p < 0.02) visual acuity. The contrast sensitivity mean was also greater in Tecnis group in monocular and binocular conditions, but without statistical signification. Visual acuity and contrast sensitivity after cataract surgery improved in both groups. But monocular and binocular visual acuity was statistically significantly better only in Tecnis group. The contrast sensitivity mean values were greater in Tecnis group but without statistically significant differences.

Wavefront-customized intraocular lenses.

Recent advances in ocular wavefront measurement and in intraocular lens materials and manufacturing methods have brought cataract surgery to the brink of a period in which customized correction of higher-order aberrations with intraocular lenses may become standard practice. Retinal image quality in pseudophakic eyes is limited by the wavefront aberrations of the cornea and the intraocular lens. The Tecnis Z9000 is the first commercially available intraocular lens designed to account for the wavefront aberrations of the cornea, specifically spherical aberration. Clinical findings with the Tecnis Z9000 intraocular lens show improved contrast sensitivity at low and mid spatial frequencies. However, if the lens decenters or tilts modestly, higher-order aberrations are created, and the lens may underperform relative to standard intraocular lenses. At present, one firm is developing an intraocular lens that may be modified in vivo with near ultraviolet energy. Such a technology offers tremendous potential for a fully customized intraocular lens. Wavefront-customized intraocular lenses offer the promise of near perfect retinal image quality, such that only diffraction, chromatic aberration, retinal sampling and neural factors will limit vision in pseudophakic eyes.

Improved functional vision with a modified prolate intraocular lens

Purpose: To evaluate whether the Tecnis Z9000 intraocular lens (IOL) (Pfizer) with a modified prolate anterior surface provides better quality of vision than a conventional spherical IOL. Setting: Oregon Eye Institute, Eugene, Oregon, USA. Methods: Patients presenting for cataract surgery who were randomly assigned to receive a Tecnis Z9000 IOL (Pfizer) or a Sensar® OptiEdge AR40e IOL (AMO) in 1 eye were followed for 3 months postoperatively. The patient could elect to have the same type of IOL implanted in the fellow eye. The results of sine-wave grating contrast sensitivity testing under mesopic and photopic conditions were compared interindividually. Results: Monocular comparison was made between the 2 IOL groups, which comprised 15 patients each. The Tecnis IOL provided significantly better contrast sensitivity at 6 cycles per degree (cpd) under photopic conditions and at 1.5 and 3 cpd under mesopic conditions. Seven patients with a Tecnis IOL and 9 patients with an AR40e IOL had subsequent implantation in the fellow eye. In all eyes, including fellow eyes, having IOL implantation, the Tecnis provided significantly better contrast sensitivity at 3 and 6 cpd under photopic conditions and at 1.5, 3, and 6 cpd under mesopic conditions. The mean contrast sensitivity in fellow eyes showed that the Tecnis IOL produced significantly better results at some spatial frequencies. Conclusions: Results show the Tecnis IOL with a modified prolate anterior surface may produce better contrast sensitivity than a standard spherical IOL under mesopic and photopic conditions. Because contrast sensitivity testing correlates well with functional vision, a goal of future research should be to evaluate patient performance using functional tests such as driving simulation.

Wavefront technology in cataract surgery.

As advances in technology allow cataract surgeons to address higher order optical aberrations, the measurement of functional vision becomes increasingly critical. Contrast sensitivity testing is assuming a prominent place in our evaluation of surgical modalities because it reflects functional vision and correlates with visual performance. The Tecnis Z9000 intraocular lens (IOL) (Pfizer, New York) is the first foldable IOL designed to correct higher order optical aberrations and represents a first step toward the integration of wavefront technology and cataract surgery. Contrast sensitivity declines with age, even in the absence of ocular pathology. Wavefront science demonstrates that the youthful crystalline lens compensates for aberrations in the cornea. The aging lens loses its balance with the cornea, as both the magnitude and the sign of its spherical aberration change. Older pseudophakic patients have generally the same contrast sensitivity as their age-matched counterparts without cataract. The Tecnis Z9000 IOL (Pfizer, New York) has been designed with a modified prolate anterior surface to compensate for the spherical aberration of the cornea, thus eliminating total ocular spherical aberration. Clinical data demonstrate that this modified prolate IOL provides superior functional vision, similar to that of younger people, and hence improves visual performance when compared with conventional spherical IOLs. It appears likely that the decline in functional vision with age involves changes in the spherical aberration of the crystalline lens. The integration of wave-front technology and lens-based surgery represents a step toward improving functional vision and quality of life for cataract patients.