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E Leite

Publications and source records attributed to E Leite.

At least 19 recordsLinked to original sources
PubMed2001

1998 European Cataract Outcome Study: report from the European Cataract Outcome Study Group.

PURPOSE: To collect clinical data on cataract surgery to allow participating surgeons to compare their performance with that of their colleagues in an anonymous manner. SETTING: Surgeons from 31 surgical units providing cataract surgery in 13 European countries. METHODS: Every patient at each participating unit having surgery during 1 study month was evaluated. Data were reported to the coordinating center at the time of surgery and at the final examination. When the study was closed 6 months after surgery, all participants were provided with the outcomes from their own patients so they could compare them with outcomes from other centers. RESULTS: The study included preoperative and intraoperative data on 2950 patients. Complete follow-up data were available for 2731 patients. The surgical audit included surgically induced astigmatism, proximity of target refraction, and the frequency of major complications. For each variable, a large variation in outcome between participating centers was found. Most centers had results both above and below average for different variables. CONCLUSION: Cataract surgery data collected from 31 units in 13 European countries allowed participants to compare their performance with that of their colleagues in an anonymous manner. Significant variation was found in the outcomes among the units, with many units reporting results above and below the averages.

Aged↗
PubMed1998

Progression of retinopathy and alteration of the blood-retinal barrier in patients with type 2 diabetes: a 7-year prospective follow-up study.

BACKGROUND: The study was carried out to evaluate the correlation between blood-retinal barrier (BRB) permeability and the progression of diabetic retinopathy (DR), defined by development of "need for photocoagulation", over a 7-year period by means of vitreous fluorometry (VF). METHODS: Forty type 2 diabetic patients with minimal or no retinopathy, aged 40-65 years (mean 53.9 + 7.3 years), were followed up prospectively for 7 years. Investigations including standard ophthalmological examination, fundus photography, fluorescein angiography and VF were performed at entry and 1, 4, 5 and 7 years later. Only one eye per patient was included in the study. Need for photocoagulation was based on Early Treatment Diabetic Retinopathy Study protocols and decided by the attending ophthalmologist. RESULTS: After 7 years of follow-up a total of 22 of the 40 eyes had received photocoagulation. The eyes that needed photocoagulation were those that had higher VF values at the entry of the study and showed higher rates of deterioration (initial values 5.1 + 1.9 vs 2.8 + 1.5 x 10(-6) min-1, P < 0.001; annual increase in leakage for the first year, 1.5 + 0.8 vs 0.5 + 1.0 x 10(-6) min-1, P < 0.001,). The eyes that did not need photocoagulation during the 7 years of follow-up showed stable VF readings (-0.1 + 1.2 x 10(-6) min-1, difference between initial values and 7 years later). CONCLUSIONS: Abnormally high VF values and their rapid increase over time are good indicators of progression and worsening of the retinopathy in diabetes type 2.

Adult↗
PubMed1998

Contrast sensitivity after implantation of diffractive bifocal and monofocal intraocular lenses.

PURPOSE: To compare contrast sensitivity (CS) after implantation of a diffractive bifocal intraocular lens (IOL) and a monofocal IOL of similar design. SETTING: Seven European centers. METHODS: In this randomized, prospective study, CS was tested 5 months after cataract and IOL implantation surgery in 115 patients with a diffractive bifocal IOL and 106 patients with a monofocal IOL. It was also tested in a subgroup of 38 patients who had bilateral implantation of a diffractive bifocal IOL. Contrast sensitivity was tested using the Vision Contrast Test System (VCTS). RESULTS: In patients with a best corrected visual acuity (BCVA) of 1.0 or better, the CS at all spatial frequencies (1.5 to 18 cycles/degree), both at distance and near, was slightly lower in the bifocal IOL group than in the monofocal group. Mean values were within the normal range. In patients with a BCVA of less than 1.0, the CS was lower and the difference between the bifocal and monofocal groups was less. In patients with bilateral bifocal IOLs, CS was better when tested bilaterally than when testing the better eye alone. Pupil size affected the results to a small degree. Contrast sensitivity appeared to improve over time after implantation of a diffractive bifocal IOL. CONCLUSIONS: In patients with cataract and no other eye pathology, the diffractive bifocal IOL with slightly reduce the CS at all spatial frequencies. In those with reduced visual acuity after cataract surgery, CS will be reduced accordingly. In this situation, the reduction from the diffractive bifocal optic would be minor.

Aged↗
PubMed1997

Permeability of the blood-retinal barrier in healthy humans. European Concerted Action on Ocular Fluorometry.

BACKGROUND: The aim of this study was to compare the inward permeability of the blood-retinal barrier in healthy subjects from six European cities. METHODS: Seventy-two healthy subjects (age 20-70 years) were selected. At 30 min and 60 min after fluorescein injection, fluorescein mass in vitreous was calculated from the concentrations measured along the optical axis of the eye. Non-protein-bound fluorescein (NPBF) concentrations were measured in plasma prepared from blood samples taken 7, 15 and 55 min after injection. Blood-retinal barrier permeability (PBRB) was calculated from the vitreous fluorescein mass and the time integral of NPBF and was corrected for the autofluorescence of ocular tissue and for lenticular light transmittance. RESULTS: Mean PBRB values +/- SD (nm.s-1) were 2.07 +/- 0.54 (Coimbra), 2.01 +/- 0.43 (Frankfurt), 2.24 +/- 0.50 (Ghent), 2.37 +/- 0.56 (Herlev), 1.89 +/- 0.44 (Leiden) and 1.74 +/- 0.38 (Porto). Differences between centers were not significant (P > 0.35). Measurements were reproducible and independent of the time after fluorescein injection (P > 0.50). A PBRB higher than 3.16 nm.s-1 or a value which had increased by 32% was considered abnormal (P < 0.05). CONCLUSION: PBRB values were similar in all centers. The results demonstrate that this is a highly sensitive and reliable method for measuring the permeability of the blood-retinal barrier.

Adult↗
PubMed1996

Comparison of a diffractive bifocal and a monofocal intraocular lens.

PURPOSE: To compare a Pharmacia diffractive bifocal intraocular lens (IOL) with a monofocal lens of the same design without the diffractive grating. SETTING: Multicenter study. METHODS: This randomized, prospective study comprised 70 patients with a monofocal IOL and 79 with a diffractive bifocal IOL. Follow-up was 5 to 6 months. Near and distance visual acuities, contract sensitivity, patient satisfaction, and spectacle use were evaluated. RESULTS: All patients achieved a best corrected visual acuity of 0.5 or better; 80% in the monofocal and 71% in the bifocal group had a best corrected visual acuity of 1.0 or better. Without correction, 93% of the bifocal and 9% of the monofocal group could read J3 or better. With distance correction, 99% and 4%, respectively, could read J3 or better. Contrast sensitivity was slightly lower in the bifocal group at distance and near for all spatial frequencies. In the bifocal group, 46% never used spectacles for near tasks. Overall satisfaction was rated good by 86% of the monofocal and 85% of the bifocal group. CONCLUSIONS: The diffractive bifocal IOL performed well at distance and near. Patients who no longer require spectacles will benefit significantly from a bifocal IOL, but many with a bifocal IOL in one eye will require spectacles for the fellow eye.

Aged↗
PubMed1996

Prevalence and surgical complications of pseudoexfoliation syndrome in Portuguese patients with senile cataract.

PURPOSE: To determine the prevalence and surgical complications of pseudoexfoliation syndrome (PES) in a Portuguese population of patients with senile cataract. SETTING: Department of Ophthalmology, Coimbra University Hospitals, Coimbra, Portugal. METHODS: In a prospective study, 183 consecutive patients with senile cataract referred to the Implant and Refractive Surgery Section of the Department of Ophthalmology were examined for PES. To determine the occurrence of intraoperative and postoperative complication of extracapsular extraction with posterior chamber intraocular lens implantation in patients with PES, two groups of similar age were compared: one with PES (n = 31) and a control group without PES (n = 31). RESULTS: The prevalence of PES in the 183 Portuguese patients with senile cataract was 23.5%. There was statistically significant difference between the two groups in the presence of phacodonesis (P < .05), insufficient intraoperative mydriasis (P < .001), need to perform sphincterotomies to facilitate nucleus expression (P < .01), and formation of pupillary fibrin membranes in the postoperative period (P < .01). These complication were more frequent in the PES group. Zonular breaks also occurred more often in patients with PES, although this was not statistically significant. CONCLUSIONS: Pseudoexfoliation syndrome was a common condition in patients with senile cataract having surgery in Portugal. Inadequate mydriasis was the major intraoperative difficulty; a pupil enlargement procedure should be performed in these cases. In the first days postoperatively, therapy with topical, subconjunctival, and systemic corticosteroids is recommended to reduce the inflammatory reaction in the anterior chamber.

Aged↗
PubMed1996

Diffusion coefficient through the blood-aqueous barrier using a standard protocol.

AIMS/BACKGROUND: Comparison of the diffusion coefficient through the blood-aqueous barrier of healthy volunteers measured in different cities with identical fluorophotometers using a standardised protocol. METHODS: Healthy volunteers aged between 20 and 70 years were studied in seven European cities. The fluorescein concentration in the anterior segment of each eye was measured with a commercial scanning fluorophotometer 30 and 40 minutes after intravenous fluorescein. The decay of non-protein bound fluorescein concentration in blood plasma was determined with the use of three blood samples taken at 7, 15, and 55 minutes after injection. The diffusion coefficient through the blood-aqueous barrier was calculated from the ratio between the fluorescein concentration in the anterior chamber and the time integral of non-protein bound fluorescein concentration in plasma using specially developed software. RESULTS: The mean values of the diffusion coefficient (SD) (X10(-4) min-1) were 4.76 (1.51) (n = 20, Brussels), 5.48 (2.33) (n = 17, Coimbra), 3.47 (2.09) (n = 12, Cologne), 6.09 (2.77) (n = 21, Frankfurt), 3.85 (1.59) (n = 11, Ghent), 4.99 (1.69) (n = 23, Leiden), and 4.87 (1.05) (n = 20, Madrid). The values between centres were similar (Kruskal-Wallis test p > 0.05) except for Cologne and Frankfurt (p = 0.013). No differences were found when repeating measurements (four centres, interval time 1-8 months, Wilcoxon paired test p > 0.39). CONCLUSION: The diffusion coefficients had similar values and standard deviations. The concerted action demonstrated the usefulness of a standardised protocol.

Adult↗
PubMed1995

Corneal endothelial permeability and aqueous humor flow using a standard protocol.

BACKGROUND: The study was carried out to compare corneal endothelial permeability and aqueous flow values of healthy volunteers measured in different countries with identical fluorophotometers using a standardized protocol. METHOD: Healthy volunteers aged between 20 and 70 years were studied in five European cities. Fluorescence scans of the anterior segment of both eyes were made using a commercial fluorophotometer. Beginning 4 h after instillation of four drops of fluorescein 10%, 12 scans of the anterior segment of each eye were performed in 2 h. The values of corneal endothelial permeability and aqueous flow were calculated with standardized software from the decay of the fluorescein concentration in the cornea and anterior chamber. RESULTS: The mean permeability values (x 10(-4) cm.min-1) +/- SD were 3.7 +/- 1.6 (n = 19; Coimbra, Portugal), 4.3 +/- 1.1 (n = 19; Frankfurt, Germany), 3.9 +/- 0.9 (n = 19; Leiden, The Netherlands) and 5.4 +/- 1.2 (n = 10; Milan, Italy). The values were not significantly different (ANOVA, P > 0.3), except those in Milan. The mean flow values (microliters.min-1) +/- SD were 2.3 +/- 0.9 (n = 17; Coimbra), 1.9 +/- 0.7 (n = 10; Cologne, Germany), 2.6 +/- 1.2 (n = 19; Frankfurt), 2.0 +/- 0.6 (n = 19; Leiden) and 1.7 +/- 0.8 (n = 10; Milan). The values were not significantly different (Kruskal-Wallis test, P > 0.1). CONCLUSIONS: Permeability and flow values in the different cities had similar values and standard deviations. The Concerted Action demonstrated the usefulness of a standardized protocol.

Adult↗
PubMed1993

Blood-retinal barrier permeability and its relation to progression of retinopathy in patients with type 2 diabetes. A four-year follow-up study.

Forty patients with late-onset diabetes (age at diagnosis 30 years or more) and minimal retinopathy as found by fundus photography were followed prospectively by repeated examination (baseline, 1 year, and 4 years). The study shows that early retinopathy changes are not permanent or invariably progressive. In the 1st year of follow-up microaneurysms worsened in 25%, improved in 10%, and remained stabilized in 65%. Vitreous fluorometry was able to detect an overall increase of 0.84 +/- 1.06 x 10(-6) min-1 in blood-retinal barrier (BRB) penetration ratios. After 4 years, 16 of the 40 patients had undergone photocoagulation (focal photo-coagulation in 11 and pan retinal photocoagulation in 5). The eyes that needed photocoagulation were the eyes that had higher fluorometry penetration ratios at the patient's entry into the study and showed a higher rate of deterioration during the 1st year of the study (5.54 +/- 1.97 vs 3.11 +/- 1.22 x 10(-6) min-1, P < 0.001, initial values; 1.52 +/- 0.76 vs 0.45 +/- 0.99 x 10(-6) min-1, P < 0.001, annual increase in leakage). The eyes that did not need photocoagulation, 24 out of 40, showed stable fluorometry readings within the 4-year period of follow-up (+0.02 +/- 0.98 10(-6) min-1). Abnormally high vitreous fluorometry values and their rapid increase over time appear to be good indicators of rapid progression and worsening of the retinopathy.

Adult↗
PubMed1993

Morphological and/or functional imagiology diagnosis of epiphora.

Several tests and examinations are necessary for an accurate diagnosis of disorders of the lacrimal drainage system. The AA studied 100 patients with epiphora, divided in two groups. Forty patients, first group (I), aged between 4 and 78 years old (mean age 47.8 +/- 9.6 years), were examined using the classical tests for the study of epiphora, sequential dacryoscintigraphy (SD) and conventional subtraction macrodacryocystrography (CSMD). In the second group (II), 60 patients (aged 45.5 +/- 8.7 years) were studied using the classical tests and by digital subtraction macrodacryocystography (DSMD). The results showed that when functional epiphora is present, there is no difference between a simple clinical approach and sequential dacryoscintigraphy. However, when information is needed regarding choice of surgical approach, DSMD appears to give the best results.

Adolescent↗
PubMed1992

Digital subtraction macrodacryocystography by videotechnique.

Digital subtraction macrodacryocystography (DSMD) has proved to be the best imaging method for diagnosing situations of stenosis of the lacrimal system. The examination is performed with a computer-controlled X-ray unit with a C-arc coupled to an image intensifier TV system with a fluoroscopic control. All the findings were recorded on videotape thus allowing good dynamic flow documentation and contributing to improved scientific analysis.

Adolescent↗
PubMed1991

Spectrophotometric analysis of sodium fluorescein aqueous solutions. Determination of molar absorption coefficient.

The usefulness of sodium fluorescein (SF) and related physical parameters were analysed. Two factors that may affect the molar absorption coefficient (epsilon) of this compound were the presence of impurities and the pH of the solution. As discrepant values can be found in the literature for that coefficient, a purification technique was used and SF quantification was performed according to sodium concentration determined by atomic absorption spectrophotometry. The molar absorption coefficient of the SF solution in phosphate buffer pH 7.4 was determined. To study the influence of pH on epsilon determination, absorption spectra at pH1, 3, 5, and 10 were also analysed.

Absorption↗
PubMed1989

[Follow-up of early diabetic maculopathy by angiography and fluorophotometry].

We evaluated prospectively for 12 months 22 patients with late-onset diabetes mellitus and minimal retinopathy by fluorescein angiography and fluorophotometry. The study showed that early retinopathy changes were not permanent or invariably progressive, but may regress. Microaneurysm gradings worsened in 24%, improved in 14% and remained stabilized in 62%. Capillary closure worsened in 33%, improved in 10% and remained stabilized in 57%. The evolution of early diabetic maculopathy is slow and irregular, and this study has shown that vitreous fluorophotometry must be included when short follow-up periods of up to 12 months are considered. Finally, eyes with higher fluorophotometry values at entry showed significantly more deterioration during the 12-months follow-up period (p less than 0.05).

Diabetes Mellitus, Type 2↗
PubMed1989

[Quantification of the foveolar zone in normal and diabetic patients].

The AA studied the foveolar avascular zone (FAZ) in diabetic patients using digital image processing (512 x 521) and comparing different methods of measurements. The results obtained from eighteen diabetic patients and twelve healthy nondiabetic controls were compared. Each patient was submitted to fluorescein angiography. The foveal avascular zone was quantified both, digitalized or by manual procedure. The different methods of analysis are compared and the results presented.

Adult↗
PubMed1988

Lens transmission and autofluorescence in renal disease.

Autofluorescence and transmission values of the lens for blue-green light were determined at two locations with the use of identical fluorophotometers: in Coimbra, Portugal, in 44 healthy controls, 15 haemodialysis and 11 renal failure patients, and in Leiden, The Netherlands, in 57 healthy controls, 23 haemodialysis and 47 renal transplant patients. The increase in lens autofluorescence as a function of age was 42% higher in the Portuguese controls than that in the Dutch controls (p less than 0.001), but the lens transmission did not differ significantly (p = 0.21). Significant differences were found between the autofluorescence values of the Portuguese haemodialysis and renal failure patients and those of age-matched local controls (+18%, p = 0.009, and +26%, p = 0.03, respectively), as well as between the lens transmission values of the Portuguese renal failure patients and those of age-matched local controls (-2%, p = 0.03). In the renal transplant patients the average autofluorescence and lens transmission values were equal to those of the local controls (within 3%) and independent of the number of anti-rejection treatments administered.

Fluorescence↗
PubMed1987

Effect of cyclospasmol on early diabetic retinopathy.

A randomized, double-blind, placebo controlled study to investigate the long-term effect of Cyclospasmol (cyclandelate) on the abnormal permeability of the blood-retinal barrier was performed in 26 patients with insulin-dependent diabetes mellitus for at least 1 year and minimal retinopathy. Cyclospasmol 400 mg or placebo capsules were taken 4 times daily for 12 months by equal numbers in both groups. Each patient underwent a routine ophthalmoscopic examination, retinal fluorescein angiography and quantitative vitreous fluorophotometry to assess the permeability of the blood-retinal barrier just before the trial and following 6 and 12 months of therapy. Laboratory tests for determining blood and urine glucose levels and blood HbA1-levels were also carried out at these assessments. Statistically significant changes in diabetic control, in HbA1-levels or in the frequency of retinal microaneurysms could not be shown in either treatment group during the trial, nor were there any significant differences in these parameters between the two groups. Analysis of fluorophotometric data on fluorescein penetration into the left posterior vitreous demonstrated significant reductions in this parameter during the trial compared to the pretreatment level in Cyclospasmol treated diabetics. These changes in the pretreatment level after 6 and 12 months also differed significantly between the two groups. However, this statistically significant beneficial reduction in fluorescein penetration into the left posterior vitreous did not occur in the right eye in the Cyclospasmol group. In placebo treated patients a consistently deleterious trend for this parameter was observed for both eyes during the one year study.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

Characterization of the early stages of diabetic retinopathy by vitreous fluorophotometry.

We compared insulin-dependent diabetic patients with minimal (16 eyes of 9 patients) or no retinopathy (45 eyes of 27 patients) to normal volunteers (20 eyes of 12 subjects) using a commercial vitreous fluorophotometer and different procedures for artifact correction. The influence of background autofluorescence was minimized through the use of a software program that subtracted a fluorophotometric scan obtained before administration of fluorescein from that obtained after its injection. We also compared two programs designed to minimize the contribution of the chorioretinal peak spread function to the readings in the vitreous. The fluorescein concentration in the posterior vitreous was then averaged within two different regions. We then assessed the influence of these data-processing methods on the spread of the results of the different groups. The clinical study showed that only the posterior vitreous concentration of fluorescein is relevant in the evaluation of the blood-retinal barrier. However, since there is a gradient of fluorescein concentration in the posterior vitreous, one needs a scanning device so that one can measure at a precise location in front of the retina. The posterior vitreous concentration of fluorescein was significantly increased in diabetic subjects with one or no aneurysms as compared with normals. Moreover, the eyes with minimal retinopathy, as judged by the presence of microaneurysms, had higher values than those without retinopathy. The clear differences among these three groups were not present when the midvitreous values were used.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗