Cristina Peris-Martínez

Phakic intraocular lenses to correct high myopia: Adatomed, Staar, and Artisan

Purpose: To evaluate the feasibility and safety of using phakic intraocular lenses (IOLs) to correct high myopia by comparing 3 IOL models: Adatomed, Staar, and Artisan. Setting: La Fe University Hospital, Department of Ophthalmology, and the Fundación Oftalmológica del Mediterráneo, Valencia, Spain. Methods: In this prospective comparative study, a phakic IOL was implanted in 217 highly myopic eyes (118 patients). Fifty‐nine eyes received an Adatomed IOL, 21 eyes a Staar IOL, and 137 eyes an Artisan IOL. The mean preoperative spherical equivalent was −15.39 diopters (D) ± 2.83 (SD), −16.00 ± 5.05 D, and −16.17 ± 2.75 D in the Adatomed, Staar, and Artisan groups, respectively. The mean follow‐up was 32.4 months (range 19 to 46 months) in the Adatomed group, 18.3 months (range 11 to 21 months) in the Staar group, and 121.4 months (range 38.4 to 154.3 months) in the Artisan group. At the follow‐up examinations, intraocular pressure (IOP), IOL pigment deposits, cataract formation, and visual acuity were evaluated. Results: The best corrected and uncorrected visual acuities improved in all eyes. No significant differences in visual acuity improvement were observed with the 3 materials, although the improvement was somewhat greater in eyes with the Artisan and Staar IOLs. The difference in mean IOP between preoperatively and the last follow‐up examination was 1.5 mm Hg in the Staar group, 1.3 mm Hg in the Adatomed group, and 1.7 mm Hg in the Artisan group (P = .36, P = .26, and P = .32, respectively). The incidence of pigment deposits was similar in the Adatomed and Staar groups, with deposits in 32 eyes (54.23%) and 8 eyes (38.1%), respectively. Anterior cataract formation was higher in the Adatomed group (44.06%) than in the Staar group (9.52%); nuclear cataract developed in 2 Adatomed eyes (1.46%) only. Conclusions: There was a higher incidence of anterior subcapsular cataract formation in the Adatomed group than in the Staar group. Delayed cataract development and the cataract type in patients with Artisan IOLs indicate that age and axial length may be prognostic factors. Factors such as IOL design, material, and placement probably affect cataract formation in eyes with posterior chamber IOLs for high myopia, particularly the Adatomed IOL.

Oxidative Stress in Keratoconus

PURPOSE The purpose of this study was to establish the alterations of oxidative stress-related markers in keratoconus (KC) corneas. METHODS A total of 6 healthy and 11 ectatic corneas (7 KC and 4 post-LASIK) were studied. Different oxidative stress-related markers were determined to assess their implication in the KC pathophysiology. Total antioxidant capacity and total nitrites present in the samples were assayed. Furthermore, lipid peroxidation products and the glutathione contents were determined, together with 4-hydroxynonenal (4-HNE) immunohistochemistry, to establish the relationship between KC and oxidative stress. RESULTS The antioxidant capacity and glutathione content in KC corneas were decreased significantly when compared with healthy corneas. Moreover, the total nitrites and lipid peroxidation were significantly elevated in the corneas with KC when compared with the controls. There was a statistically significant difference in the amount of HNE-positive cells in KC corneas when compared with healthy corneas by immunohistochemistry. Post-LASIK ectatic corneas and KC corneas showed similar results. CONCLUSIONS The increased levels of oxidative stress markers and the decreased antioxidant capacity and antioxidant defenses in KC corneas, as well as in the post-LASIK ectatic corneas, indicate that oxidative stress might be involved in the development of this disease and may provide new insights for its prevention and treatment in the future.

Posterior chamber phakic intraocular lenses to correct high myopia: a comparative study between Staar and Adatomed models.

PURPOSE To determine the feasibility of using posterior chamber phakic intraocular lenses (PIOLs) to treat high myopia, comparing two different models, Staar and Adatomed. METHODS Twenty-four eyes from 12 patients were studied prospectively. A phakic Staar IOL was implanted in one eye of each patient, and the other eye received a phakic Adatomed IOL. Patients with uveitis or ocular trauma prior to ocular surgery, diabetic retinopathy, or capsular pseudoexfoliation were excluded. The mean preoperative spherical equivalent refraction was -16.00 +/- 5.05 D for the Staar group and -15.39 +/- 2.83 D for the Adatomed group. Average follow-up was 32.4 months (range, 19 to 46 mo) for the Adatomed group and 18.3 months (range, 11 to 21 mo) for the Staar group and included evaluation of intraocular pressure, intraocular lens pigment deposits, lens decentration, anterior subcapsular cataract, and visual acuity. RESULTS Spectacle-corrected and uncorrected visual acuity improved in all eyes in both groups. No statistically significant differences in visual acuity gain were observed with the two materials (Student t-test, P = .08 for the Staar group and P = .6 for the Adatomed group), although the gain in visual acuity was somewhat greater with the Staar PIOLs. The difference in mean intraocular pressure before surgery and at last follow-up was 1.5 mmHg for the Staar group and 2.3 mmHg for the Adatomed group (P = .36). The incidence of lens pigment deposits was the same in both groups (41.66%), with deposits in 5 of the 12 eyes in both groups. The incidence of lens decentration was higher in the Adatomed group (5/12; 41.66%) than in the Staar group (2/12; 16.7%). Anterior subcapsular cataract was higher in the Adatomed group (4/12; 33.3%) than in the Staar group (3/12; 25%). CONCLUSIONS There was a higher incidence of lens decentration and anterior subcapsular cataract in the Adatomed group than in the Staar group.

Rate of cataract formation in 343 highly myopic eyes after implantation of three types of phakic intraocular lenses.

PURPOSE To assess the feasibility of using phakic intraocular lenses (PIOL) to treat high myopia, and evaluate the incidence of cataract, comparing three different lens types. METHODS From 1989 to 2002, we implanted three different phakic intraocular lenses (PIOL) in 343 eyes of 232 patients; 231 eyes recieved an Ophtec (Worst-Fechner model, iris-claw), 89 an Adatomed (silicone posterior chamber), and 23 a Staar (posterior chamber, models V2, V3, V4). Average follow-up was 96.2 months for the Ophtec group, 31.5 months for the Adatomed group, and 19.3 months for Staar group. Eyes that subsequently developed cataract were studied for clinical evolution and had PIOL explantation and cataract extraction. RESULTS Nuclear cataract developed in 7 of 231 eyes (3.04 %) with an Ophtec lens. Anterior subcapsular cataract developed with the two types of posterior PIOLs (Adatomed group: 38/89 eyes, 42.69%; Staar group: 3/23 eyes, 13.04%). Anterior subcapsular cataract in the Adatomed group developed more rapidly compared to the Staar group. We explanted 7 lenses in the Ophtec group, 16 lenses in the Adatomed group, and 2 lenses in the Staar group (models V2 and V3 only). Patient age older than 40 years at implantation of PIOLs and axial length greater than 30 mm were factors significantly related to nuclear cataract formation and the Ophtec lens. However, these two factors had a weaker correlation with the posterior phakic lenses (Adatomed, Staar) for high myopia than with the Ophtec lens. Postoperative best spectacle-corrected visual acuity remained stable after explantation, phacoemulsification, and posterior chamber lens implantation. CONCLUSIONS Delayed cataract development and cataract type (nuclear) in patients with an Ophtec lens and the variables of patient age (>40 yr) and axial length (>30 mm) may considered prognostic factors. Other factors such as lens design, material, and placement probably influenced cataract formation in patients with the Adatomed and Staar PIOLs. The lens styles used in this study are no longer manufactured.

CYP2E1 in the Human Retinal Pigment Epithelium: Expression, Activity, and Induction by Ethanol.

PURPOSE Cytochrome p450 2E1 (CYP2E1) is a detoxifying enzyme with particular affinity for ethanol (EtOH) expressed in several tissues. Although CYP2E1 has been identified in human RPE, nothing is known about its metabolic activity. Expression of CYP2E1 and activity after EtOH exposure have been studied in human RPE and ARPE-19 cells. METHODS Ethanol-induced CYP2E1 mRNA expression was analyzed by RT-PCR and quantitative PCR (qPCR) from human donor RPE as well as from ARPE-19 cells. Expression of CYP2E1 protein was determined by Western blot. Cytoplasmic CYP2E1 location also was demonstrated by immunocytochemistry. Cell viability was studied by the colorimetric assay XTT after EtOH treatment. Diallyl sulfide (DAS) was used to inhibit CYP2E1 activity. The microsomal CYP2E1 activity assay was determined by quantification of 4-nitrocatechol (4NC) formation through HPLC. RESULTS Relevant CYP2E1 mRNA levels are present in human RPE. Ethanol augmented the formation of reactive oxygen species (ROS) in ARPE-19 cells. Expression of CYP2E1 mRNA, CYP2E1 protein activity, and ROS production were induced by ethanol in a concentration-dependent manner. Interestingly, the treatment with DAS reduced all the aforementioned increased values. The presence of CYP2E1 in both hRPE and ARPE-19 cells reinforces the protective role of the RPE and strongly suggests additional roles for CYP2E1 related to vision.

Visual Outcomes After Cataract Surgery: Multifocal Versus Monofocal Intraocular Lenses

PURPOSE To evaluate visual outcomes, spectacle independence, and quality of life among nonastigmatic and astigmatic patients who received AcrySof IQ ReSTOR toric or nontoric multifocal intraocular lenses (IOLs) (Alcon Laboratories, Fort Worth, TX) compared with those who received commercially available nontoric monofocal IOLs after bilateral cataract removal. METHODS This randomized, patient- and observer-technician-masked study was conducted at 20 sites in Europe. Patients were randomized to receive monofocal (nontoric only) or multifocal (nontoric or toric, as needed) IOLs. Primary efficacy endpoints included percentage of patients achieving binocular uncorrected distance and near acuity of 0.1 logMAR or better (20/25 Snellen), spectacle independence, and scores on the National Eye Institute Refractive Error and Quality of Life questionnaire domains. Safety endpoints included adverse events and refractive error within 0.5 and 1.0 diopters. RESULTS In the multifocal group (n = 108) versus the monofocal group (n = 100), significantly more patients achieved uncorrected distance and near acuity of 0.1 logMAR or better (45.7% vs 2.1%; P < .0001) and spectacle independence (73.3% vs 25.3%; P < .0001) at 6 months. The percentage of patients who achieved uncorrected distance visual acuity of 20/40 or better at 6 months was 92% in the multifocal group and 97% in the monofocal group. National Eye Institute Refractive Error and Quality of Life scores were significantly better for dependence on correction in the multifocal group (P < .0001) and for glare in the monofocal group (P = .0157); other domain scores were similar between groups. No significant trends in study device-related adverse events were observed. CONCLUSIONS Monofocal and multifocal IOLs provided good clinical outcomes. More patients receiving multifocal IOLs attained better uncorrected visual acuity at a range of distances and spectacle independence compared with patients who received monofocal IOLs. Monofocal IOLs were associated with better patient-reported scores for glare compared with multifocal IOLs; however, scores for patient satisfaction were significantly better in the multifocal group.

Image quality comparison of two multifocal IOLs: influence of the pupil.

PURPOSE To evaluate the effect of pupil size on image quality of a sectorial multifocal intraocular lens (IOL), the Lentis Mplus (Oculentis GmbH, Berlin, Germany), and the Acri.LISA IOL (Carl Zeiss Meditec, Jena, Germany). METHODS The authors measured the MTFs of the Lentis Mplus LS-312 IOL and the Acri.LISA 366D IOL with three different sizes of pupil diameters: 3, 4, and 5 mm. The MTF was calculated from the cross-line spread function recorded with the OPAL Vector System (Image Science Ltd., Oxford, UK) by using fast Fourier-transform techniques. RESULTS In distance focus, the image quality provided by the Lentis Mplus IOL was better than that of the Acri. LISA IOL with all pupil diameters. In near focus, the MTF of the Acri.LISA IOL was better with a 3-mm pupil, but poor with larger pupils. The aberration effect was equal in both IOLs in distance focus, but in near focus and with a 3-mm pupil, the Acri.LISA IOL was less affected by the aberration than the Lentis Mplus IOL. CONCLUSION The Lentis Mplus IOL provides better distance image quality than the Acri.LISA IOL, whereas the near image quality of the Acri.LISA IOL is better with small-pupil diameter. The sectorial design makes this IOL more suitable for patients with a pupil diameter greater than 3 mm.

New Trends in Anterior Segment Diseases of the Eye

Disorders of the anterior segment of the eye are leading causes of ocular morbidity. Such conditions include dry eye conditions, infections, traumas of various types, inflammatory reactions, hereditary disorders, and cataract. For a number of these patients, the rule is a continuous progression and aggravation of symptoms. The end stage is varying degrees of visual loss with or without pain. Despite continuous advances in ophthalmology, a number of these patients represent a challenge even in highly specialized clinics in western countries. On a worldwide basis, such conditions represent a significant public health problem. Cataract and loss of corneal transparency are still two of the most common causes of blindness worldwide [1]. While cataract is a disorder of the adult and aged population, blindness due to corneal opacities is observed in all age groups. In children, loss of corneal transparency represents the third most common cause of blindness. During the past two decades, translational research has increased our ability to understand the pathogenesis of, and also to treat, selected disorders of the ocular surface and cornea. Although still in their shaping and improved by continuous translational and clinical research, procedures for ex vivo production of corneal and conjunctival epithelial tissue allow treatment of patients with previously untreatable corneal disorders [2, 3]. Refinement of corneal transplant procedures permits targeted intervention and replacement of opaque and nonfunctioning tissues with lamellar donor tissue [4, 5]. By such techniques, the volume of foreign tissue with a potential for stimulation of immunoreactions is reduced as is the trauma induced by the surgical intervention. However, there is a pronounced lack of donor corneas. In western countries, one main indication for corneal transplantation is loss of endothelial function. Ongoing research within the field of tissue engineering will provide procedures for production of transplantable layers of corneal endothelium and thereby add a new and significant tool to our treatment options [6]. Procedures for cataract surgery are continuously being advanced, accompanied by a decline in the rate of complications such as astigmatism and corneal endothelial loss with subsequent corneal hydration [7, 8]. Due to the complexity of challenges within these areas, further progress relies to a significant extent on interaction between clinical and basic research environments. In translational research projects, extraction of information is facilitated by cooperation between clinical and basic research environments [9, 10]. The intent is to warrant that advances in basic and clinical knowledge may serve a purpose: a better understanding of the disease pathophysiology to ensure a better disease prevention, new diagnostic procedures, and novel types of treatment including drugs, whose final end point may be preclinical or clinical testing. Francisco Javier Romero Bjorn Nicolaissen Cristina Peris-Martinez

Lens opacities in Valencia, Spain.

Purpose. To evaluate the most common lens opacities in Valencia (Spain), analyzed by gender, grade, and type of cataracts. The results are compared with other studies performed at other geographical latitudes and on different races. Methods. A total of 1951 eyes of patients diagnosed with cataracts, aged between 30 and 96 years, were evaluated in accordance with age, gender, type and degree of the cataract, bilaterality and symmetry of this disease. Lens Opacities Classification System III was used to classify the cataract and the degree was graded as mild or moderate to advanced. Results. The most common type of cataract is corticonuclear in the elderly and subcapsular in younger subjects. The most common are nuclear (28.4%) followed by cortical (6.2%), if combined cataracts are ruled out. There is a greater incidence of cortical cataracts in women (70%) and subcapsular cataracts in men (70%). Conclusions. The results suggest the existence of a gender factor in cataract formation and coincide with those obtained in similar studies performed in areas at a similar latitude (40° N) and with different race population. The geographical location (intensity and length of exposure to solar radiation) seems to be a determining factor in the formation of a specific type of cataract, more than race, although there are other factors that contribute in the formation of a specific type of cataract.

A rapid method for measuring intraocular lens power in vitro with a focimeter

In this paper we describe a new method for measuring the intraocular lens (IOL) power using a focimeter, a negative ophthalmic lens and a saline solution (0.9% NaCl). To test this we measured the power of 58 different IOLs and we compared them with the power stated by the manufacturer. Despite the limitations, the results show a good correlation.