Newton Kara-Junior

Microkeratome versus femtosecond flaps: accuracy and complications.

Purpose of review To update the knowledge on differences between mechanical microkeratome and femtosecond flaps for laser in-situ keratomileusis (LASIK) in terms of accuracy and complications. Recent findings Corneal flaps created with the femtosecond laser present a more planar architecture and provide greater precision in flap diameter and thickness; a more uniform flap thickness across the flap diameter and it allows the surgeon to programme the angulation of the flap periphery. Femtosecond LASIK flaps are classically related to complications derived from a more intense inflammatory response, such as diffuse lamellar keratitis and transient light-sensitivity syndrome. Newer femtosecond models allow for much lower energy delivery to cut the flap, to the point the overall inflammatory response is not significantly different from the microkeratome. The incidence of complications such as epithelial defect and flap dislocations is higher with microkeratome flaps. Summary This review examines the accuracy and complications of flaps created with femtosecond and microkeratome. Both femtosecond and microkeratome are able to create accurate LASIK flaps. Femtosecond LASIK flaps represent significant improvement in morphology and predictability with implications for safety.

Ocular findings in patients with systemic sclerosis

OBJECTIVE: To evaluate the frequency and characteristics of ocular manifestations in outpatients with systemic sclerosis. METHODS: In this cross-sectional study, 45 patients with systemic sclerosis were enrolled. Data regarding demographics, disease duration and subtype, age at diagnosis, nailfold capillaroscopic pattern and autoantibody profile were collected, and a full ophthalmic examination was conducted. Parametric (Students t-test) and nonparametric (Mann-Whitney U test) tests were used to compare continuous variables. Fishers exact test was used to compare categorical data. P values < 0.05 were considered significant. RESULTS: Twenty-three subjects (51.1%) had eyelid skin changes; 22 (48.9%) had keratoconjunctivitis sicca, 19 (42.2%) had cataracts, 13 (28.9%) had retinal microvascular abnormalities and 6 (13.3%) had glaucoma. Eyelid skin changes were more frequent in patients with the diffuse subtype of systemic sclerosis and were associated with a younger age and an earlier age at diagnosis. Cataracts were presumed to be age-related and secondary to corticosteroid treatment. There was no association between demographic, clinical or serological data and keratoconjunctivitis sicca. The retinal microvascular abnormalities were indistinguishable from those related to systemic hypertension and were associated with an older age and a severe capillaroscopic pattern. CONCLUSIONS: Eyelid skin abnormalities and keratoconjunctivitis sicca were the most common ocular findings related to systemic sclerosis. Some demographic and clinical data were associated with some ophthalmic features and not with others, showing that the ocular manifestations of systemic sclerosis are characterized by heterogeneity and reflect the differences in the implicated pathophysiological mechanisms.

Visual performance of an apodized diffractive multifocal intraocular lens with +3.00-d addition: 1-year follow-up.

PURPOSE To determine whether implantation of a multifocal intraocular lens (IOL) with a lower addition (+3.00 diopters [D]) at the lens plane results in better intermediate visual acuity 1 year after surgery compared with a multifocal IOL with higher addition (+4.00 D). METHODS This prospective, randomized, double-masked study included 80 eyes from 40 patients. Twenty patients were implanted bilaterally with the ReSTOR +3.00-D add IOL and 20 patients were implanted bilaterally with the ReSTOR +4.00-D add IOL. Primary outcome measures were distance, intermediate, and near visual acuity. Secondary outcomes were defocus curves, best reading distance, mesopic and photopic contrast sensitivity, quality of life, and spectacle independence. Monocular and binocular visual acuity were measured as uncorrected and corrected distance visual acuity at 4 m, uncorrected near and distance-corrected near visual acuity at 40 cm, and uncorrected intermediate visual acuity and distance-corrected intermediate visual acuity at 50, 60, and 70 cm. RESULTS Twelve months postoperatively, no statistically significant difference between groups in distance and near visual acuity was noted. The ReSTOR +3.00-D add group performed better than the ReSTOR +4.00-D add group at all intermediate distances studied. The ReSTOR +4.00-D group chose a reading distance 8 cm closer than the +3.00-D group. Both groups performed similarly with respect to contrast sensitivity, quality of life, and spectacle independence rates. CONCLUSIONS Patients implanted with a multifocal IOL with lower addition (ReSTOR +3.00 D) had better performance at intermediate distances compared with the ReSTOR +4.00-D add IOL with similar performance for distance and near visual acuity, contrast sensitivity, and quality of life.

Effects of blue light–filtering intraocular lenses on the macula, contrast sensitivity, and color vision after a long-term follow-up

PURPOSE: To evaluate the possible side effects and potential protection 5 years after implantation of an intraocular lens (IOL) with a blue‐light filter (yellow tinted). SETTING: Ophthalmology Department, University of São Paulo, São Paulo, Brazil. DESIGN: Prospective randomized clinical study. METHODS: Patients with bilateral visually significant cataract randomly received an ultraviolet (UV) and blue light–filtering IOL (Acrysof Natural SN60AT) in 1 eye and an acrylic UV light–filtering only IOL (Acrysof SA60AT) in the fellow eye. The primary outcome measures were contrast sensitivity, color vision, and macular findings 5 years after surgery. RESULTS: The study enrolled 60 eyes of 30 patients. There were no significant clinical or optical coherence tomography findings in terms of age‐related macular degeneration in any eye. There were no statistically significant differences in central macular thickness between the 2 IOL groups (P=.712). There were also no significant between‐group differences under photopic or scotopic conditions at any spatial frequency studied. No statistically significant differences in the color discrimination test were found between the 2 IOL groups (P=.674). CONCLUSIONS: After 5 years, there were no significant differences in color perception, scotopic contrast sensitivity, or photopic contrast sensitivity between the blue light–filtering (yellow‐tinted) IOL and the IOL with a UV‐light filter only (untinted). The potential advantage of the tinted IOL in providing protection to macular cells remains unclear. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Modulation transfer function and optical quality after bilateral implantation of a +3.00 D versus a +4.00 D multifocal intraocular lens

PURPOSE: To determine whether the improvement in intermediate vision after bilateral implantation of an aspheric multifocal intraocular lens (IOL) with a +3.00 diopter (D) addition (add) occurs at the expense of optical quality compared with the previous model with a +4.00 D add. SETTING: Department of Ophthalmology, University of São Paulo, São Paulo, Brazil. DESIGN: Prospective randomized double‐masked comparative clinical trial. METHODS: One year after bilateral implantation of Acrysof Restor SN6AD1 +3.00 D IOLs or Acrysof Restor SN6AD3 +4.00 D IOLs, optical quality was evaluated by analyzing the in vivo modulation transfer function (MTF) and point‐spread function (expressed as Strehl ratio). The Strehl ratio and MTF curve with a 4.0 pupil and a 6.0 mm pupil were measured by dynamic retinoscopy aberrometry. The uncorrected and corrected distance visual acuities at 4 m, uncorrected and distance‐corrected near visual acuities at 40 cm, and uncorrected and distance‐corrected intermediate visual acuities at 50 cm, 60 cm, and 70 cm were measured. RESULTS: Both IOL groups comprised 40 eyes of 20 patients. One year postoperatively, there were no statistically significant between‐group differences in the MTF or Strehl ratio with either pupil size. There were no statistically significant between‐group differences in distance or near visual acuity. Intermediate visual acuity was significantly better in the +3.00 D IOL group. CONCLUSION: Results indicate that the improvement in intermediate vision in eyes with the aspheric multifocal + 3.00 D add IOL occurred without decreasing optical quality over that with the previous version IOL with a +4.00 D add. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Cataract surgery: expectations of patients assisted during a community project in São Paulo, state of São Paulo, Brazil

OBJECTIVE To identify social characteristics and expectations of individuals seen during a community project for the treatment of senile cataracts. Expected results from their eye surgery and its consequences to their quality of life were studied as well. METHODOLOGY Cataract patients (visual acuity equal to or lower than 0.2 in the more superior eye) aged 50 years or over, were surveyed by means of interviews held during their visit at the Cataract Project in São Paulo city, State of São Paulo, Brazil, in 1999. RESULTS The sample was composed of 331 subjects of low socioeconomic level ranging in age from 50 to 97 years (average = 71.8 years). Expectation of total recovery from the cataract condition by means of surgery was declared by 80.0% of the respondents, with no significant differences between male and female subjects (P < 0.1723). Hope to resume manual activities was expressed by 59.8%. CONCLUSION A predominance of expectations of resuming normal activity and achieving a better quality of life after cataract surgery were identified.

Comparison of reading performance after bilateral implantation of multifocal intraocular lenses with +3.00 or +4.00 diopter addition

PURPOSE: To compare reading ability after cataract surgery and bilateral implantation of multifocal intraocular lenses (IOLs) with a +3.00 diopter (D) addition (add) or a +4.00 D add. SETTING: Department of Ophthalmology, University of São Paulo, São Paulo, Brazil. DESIGN: Prospective comparative study. METHODS: Patients scheduled for cataract surgery were randomly assigned to bilateral implantation of an aspheric AcrySof ReSTOR multifocal IOL with a +3.00 diopter (D) addition (add) or a +4.00 D add. The reading speed, critical print size, and reading acuity were measured binocularly with best correction using MNREAD acuity charts 6 months after surgery. Patients were tested with the chart at the best patient‐preferred reading distance and at 40 cm. Binocular uncorrected and best distance‐corrected visual acuities at far and near were also measured. RESULTS: The study enrolled 32 patients. At the best reading distance, the results were similar between the 2 IOL groups in all reading parameters. When tested at 40 cm, reading speed at all print sizes from 0.3 to 0.0 (all P<.001), critical print size (P<.001), and reading acuity (P = .014) were statistically significantly better in the +3.00 D IOL group than in the +4.00 D IOL group. Uncorrected and corrected visual acuities at far and near were similar between the 2 groups. CONCLUSION: Although the 2 IOL groups had similar performance in reading parameters, patients had to adjust to their best reading distance. The +3.00 D IOL performed better than the +4.00 D IOL at 40 cm. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Effect of the AcrySof Natural intraocular lens on blue–yellow perimetry

PURPOSE: To assess the differences in blue–yellow perimetry values in patients with an AcrySof Natural intraocular lens (IOL) in 1 eye and a conventional AcrySof IOL in the fellow eye. SETTING: Cataract and glaucoma clinics of a medical school associated with a public hospital in Brazil. METHODS: Forty‐six patients had bilateral phacoemulsification and implantation of an AcrySof SN60AT IOL (Alcon) in 1 eye and an MA30AC IOL (Alcon) in the fellow eye. Blue–yellow perimetry was performed in both eyes, and the data were analyzed in blinded fashion using the Mann‐Whitney U test. RESULTS: No statistically significant differences were observed in short‐wavelength automated perimetry (SWAP) values between the 2 IOLs. CONCLUSION: There was no interference by the yellow filter of the AcrySof Natural IOL in blue–yellow perception as determined by SWAP.

Wavefront Analysis, Contrast Sensitivity, and Depth of Focus After Cataract Surgery With Aspherical Intraocular Lens Implantation

PURPOSE To determine whether implantation of an aspherical intraocular lens (IOL) results in reduced ocular aberrations and improved contrast sensitivity after cataract surgery without critical reduction of depth of focus. DESIGN Double-blinded, randomized, prospective study. METHODS In an intraindividual study of 25 patients with bilateral cataract, an aspherical IOL (Akreos Advanced Optic [AO]; Bausch & Lomb, Inc., Rochester, New York, USA) was implanted in one eye and a spherical IOL (Akreos Fit; Bausch & Lomb, Inc) in the fellow eye. Higher-order aberrations with a 5- and 6-mm pupil were measured with a dynamic retinoscopy aberrometer at 1 and 3 months after surgery. Uncorrected and best-corrected visual acuity and contrast sensitivity under mesopic and photopic conditions also were measured. Distance-corrected near and intermediate visual acuity were studied as a measurement of depth of focus. RESULTS There was no statistically significant difference between eyes in uncorrected and best-corrected visual acuity at 1 and 3 months after surgery. There was a statistically significant between-group difference in contrast sensitivity under photopic conditions at 12 cycles per degree and under mesopic conditions at all spatial frequencies. The Akreos AO group obtained statistically significant lower values of higher-order aberrations and spherical aberration with 5- and 6-mm pupils compared with the Akreos Fit group (P < .05). There was no significant difference in distance-corrected near and intermediate visual acuity between both groups. CONCLUSIONS Aspherical aberration-free Akreos AO IOL induced significantly less higher-order aberrations and spherical aberration than the Akreos Fit. Contrast sensitivity was better under mesopic conditions with the Akreos AO with similar results of depth of focus.

Role of optical coherence tomography on corneal surface laser ablation.

This paper focuses on reviewing the roles of optical coherence tomography (OCT) on corneal surface laser ablation procedures. OCT is an optical imaging modality that uses low-coherence interferometry to provide noninvasive cross-sectional imaging of tissue microstructure in vivo. There are two types of OCTs, each with transverse and axial spatial resolutions of a few micrometers: the time-domain and the fourier-domain OCTs. Both have been increasingly used by refractive surgeons and have specific advantages. Which of the current imaging instruments is a better choice depends on the specific application. In laser in situ keratomileusis (LASIK) and in excimer laser phototherapeutic keratectomy (PTK), OCT can be used to assess corneal characteristics and guide treatment decisions. OCT accurately measures central corneal thickness, evaluates the regularity of LASIK flaps, and quantifies flap and residual stromal bed thickness. When evaluating the ablation depth accuracy by subtracting preoperative from postoperative measurements, OCT pachymetry correlates well with laser ablation settings. In addition, OCT can be used to provide precise information on the morphology and depth of corneal pathologic abnormalities, such as corneal degenerations, dystrophies, and opacities, correlating with histopathologic findings.