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At least 469 records · Page 26Linked to original sources

PubMed2006

Visual acuity change after intravitreal triamcinolone in various types of exudative age-related macular degeneration.

OBJECTIVE: The aim of this study was to compare the visual acuity change after an intravitreal high-dose injection of triamcinolone acetonide (TA) in various types of exudative age-related macular degeneration (AMD). PARTICIPANTS: The interventional comparative case series study included 142 patients (146 eyes) with progressive exudative AMD differentiated into the occult type (n = 78; 53.4%), minimal classic type (n = 45; 30.8%), predominantly classic type (n = 17; 11.6%), and the purely classic type (n = 6; 4.1%). Mean follow-up was 9.7 +/- 7.0 months (3-35.7 months). METHODS: Single intravitreal injection of approximately 20 mg of TA. OUTCOME MEASURES: Visual acuity, intraocular pressure (IOP). RESULTS: Gain in visual acuity measured at 1 month (P = 0.20), 2 months (P = 0.43), and at 3 months (P = 0.38) after the intravitreal injection of triamcinolone and maximal gain in visual acuity during the whole follow-up (P = 0.81) did not vary significantly between the 4 study groups. Correspondingly, the size of a retinal pigment epithelium detachment was not significantly associated with the change in visual acuity at 1 month (P = 0.62), 2 months (P = 0.24), 3 months (P = 0.96), or the maximal gain in visual acuity during follow-up (P = 0.93). The amount of rise in IOP, compared with the baseline value (6.5 +/- 7.4 mmHg), was statistically not associated with the type of subfoveal membrane (P = 0.20; 95% confidence interval: -0.52, 2.45). CONCLUSIONS: The change in visual acuity and the rise in IOP in patients with exudative AMD receiving an intravitreal triamcinolone monotherapy is statistically independent of the type of subfoveal membrane, including the size of a retinal epithelium detachment.

Aged↗

PubMed2000

Older adults, diabetes mellitus and visual acuity: a community-based case-control study.

MAIN OBJECTIVES: to screen for impaired distance visual acuity in older adults living at home, both with and without diabetes mellitus to determine whether diabetes increases the likelihood of visual impairment and to identify associated factors. DESIGN: case-control study. SETTINGS: three districts of Wales: North Clwyd, Powys and South Glamorgan, with assessments in subjects' homes. SUBJECTS: 385 with diabetes mellitus and 385 age- and sex-matched controls. MAIN OUTCOME MEASURES: visual acuity measures, short form (SF)-36 quality of life scores RESULTS: we observed impairment of visual acuity in 40% of those with diabetes mellitus and 31% of controls. Diabetes was associated with an increased risk of visual impairment [odds ratio 1.50 (95% confidence interval 1.09-2.05), P = 0.013]. The pinhole test identified uncorrected refractive error in 11% of the 63 patients with diabetes and 12% of the 49 controls who wore glasses, and in 51% of the 91 patients and 84% of the 69 controls who did not wear glasses (P < 0.001). Increasing age (P < 0.001) and female sex (P = 0.014) were significantly associated with visual impairment in both groups, whilst history of foot ulceration (P = 0.001), duration of diabetes (P = 0.018) and treatment with insulin (P < 0.001) were significantly associated with visual impairment in subjects with diabetes. We observed a significant association between impaired visual acuity and five domains of the SF-36 (physical and social functioning, mental health, vitality, and health perceptions; P < 0.01 in each case). CONCLUSION: older adults living at home have a high prevalence of uncorrected visual impairment. Diabetes mellitus is associated with significantly increased risk of visual loss. This impairment is associated with detriments in health-related quality of life. We recommend earlier use of optometry services and assessment of visual acuity by clinicians.

Aged↗

PubMedDate not supplied

Visual acuity testing in cataract--an insight (cataract classification density based).

The senile cataracts have been graded on the basis of density objectively. The letter visual acuity, laser interferometric visual acuity and pin hole visual acuity were compared in various grades of cataracts and controls (phakic and aphakic) in 140 eyes. It was found that good correlation exists in all eyes except when cataract density is grade III or IV. The laser interferometry has good prognostic value when the predictability is assessed in early stages of cataract (Grade I & II).

Cataract↗

PubMed1988

A clinical index for predicting visual acuity after cataract surgery.

We developed a clinical index for predicting postoperative visual acuity of cataract patients and cross-validated it using data from 182 patients aged 70 years and older. The index consisted of four statistically combined indicators: age, preoperative visual acuity, frequency of reading, and comorbidity. Validation of the index included comparisons to two standard technical instruments for measurement of retinal visual acuity. For the clinical index, 72% of predictions were accurate within one Snellen line of postoperative visual acuity compared to 37% using a laser interferometer and 33% using a potential acuity meter. Testing of the clinical index's external validity using data from 111 patients in a different ophthalmology clinic disclosed 61% of predictions accurate within one Snellen line.

Aged↗

PubMed2000

Dynamic visual acuity and coincidence-anticipation timing by experienced and inexperienced women players of fast pitch softball.

This study examined the relationship between dynamic visual acuity and coincidence-anticipation timing in 16 inexperienced and 16 experienced women's fast pitch softball players. Pearson-product correlations indicated a low relationship between dynamic visual acuity and coincidence-anticipation timing. The correlations for dynamic visual acuity and coincidence anticipation between experienced and inexperienced dynamic visual acuity were not significant. A significant difference was found between the mean dynamic visual acuity of the two groups, i.e., experienced players had better dynamic visual acuity than inexperienced players. Analysis of variance of constant errors, variable errors, and absolute errors of coincidence anticipation indicated no significant differences between groups or across the three accuracy scores. The interaction between experience and accuracy was not significant.

Achievement↗

PubMed2004

Test-retest reliability of swept visual evoked potential measurements of infant visual acuity and contrast sensitivity.

The aim of the study was to describe variations in swept visual evoked potential (SWEEP-VEP) assessment of visual acuity and contrast sensitivity in infants and to evaluate the best way to estimate visual performance from obtained SWEEP-VEP data. The visual performance of 92 infants (6-40 wk of age) was measured in two separate visits. Results were verified with repeated tests in seven adults. There was a strong association between the two measurements of infant visual acuity (r = 0.91, p < 0.001), with no constant bias and an inter-assay coefficient of variation of 8.4%. The intra-assay coefficient of variation was 17% and in repeated sessions all obtained acuity measures were normally distributed, indicating that the mean and not the maximum threshold best estimates visual acuity. This estimate of visual acuity also had lower test-retest variability than those calculated from the maximum threshold or threshold from the average EEG signals (p = 0.001). Test-retest measures of infant contrast sensitivity had a correlation coefficient of 0.72 (p < 0.001) and an inter-assay coefficient of variation of 23%. With the observed test-retest variability, SWEEP-VEP is less valid for estimating the visual performance of individual subjects, but it can give reliable group means. This method was well suited to describe visual development in the infants, which for acuity as well as contrast sensitivity increased by 0.64 octave per doubling in age. However, the variability of the SWEEP-VEP method can be a limiting factor, for example, in the assessment of the potential effect of dietary docosahexaenoic acid in a homogeneous group of infants.

Adult↗

PubMed2005

Relation between reduction of foveal thickness and visual acuity in diabetic macular edema treated with intravitreal triamcinolone.

PURPOSE: To evaluate the correlation between improvement in visual acuity and the reduction of foveal thickness after a single intravitreal injection of 4 mg of triamcinolone in diabetic macular edema. DESIGN: Prospective, interventional, nonrandomized clinical trial. METHOD PATIENTS: In a prospective study 24 eyes with diabetic macular edema were treated with an intravitreal injection of 4 mg of triamcinolone acetonide. MAIN OUTCOME MEASURES: Best-corrected logMAR visual acuity and optical coherence tomography were performed at baseline and 3 months after the treatment. RESULTS: At baseline the average foveal thickness was 462 +/- 154 microm (95% confidence interval, 397-527 microm) and at 3 months 257 +/-114 microm (95% confidence interval, 209-305 microm) (P < .0001). The best-corrected logMAR average visual acuity was 60.5 +/- 10.5 (95% confidence interval, 56.0-65.0) ETDRS letters at baseline compared with 65.5 +/- 11.1 (95% confidence interval, 60.8-70.1) 3 months after the injection (P = .0001). There was no correlation between the improvement in visual acuity and the reduction of foveal thickness (r = 0.054, P = .8), but there was a correlation between reduction in foveal thickness and the age of the patients (r = 0.53, P = .008). CONCLUSION: A single injection of 4 mg of intravitreal triamcinolone acetonide effectively reduces the foveal thickness in diabetic macular edema and improves visual acuity, but there does not appear to be a strong correlation between the reduction of foveal thickness and the improvement in visual acuity.

Adult↗

PubMed2002

Relationship of AcrySof acrylic and PhacoFlex silicone intraocular lenses to visual acuity and posterior capsule opacification.

PURPOSE: To compare the changes in visual acuity and the development of posterior capsule opacification (PCO) with AcrySof acrylic intraocular lenses (IOLs) (Alcon Laboratories) and second-generation PhacoFlex silicone IOLs (Allergan ). SETTING: Eye Associates of New Mexico and Southwest Colorado, Albuquerque, New Mexico, USA. METHODS: Medical charts of patients having cataract extraction with implantation of an AcrySof MA30BA or MA60BM (MA30/60) or PhacoFlex SI-30NB or SI-40NB (SI-30/40) IOL between January 1995 and June 1997 were abstracted. Analyzed were the changes in visual acuity and development of PCO 1 month postoperatively and at the last available ophthalmologist visit or the visit before neodymium:YAG (Nd:YAG) capsulotomy. RESULTS: Patients with MA30/60 acrylic IOLs were significantly older, had a worse preoperative best corrected visual acuity (BCVA), and had more concomitant ocular diseases than those with SI-30/40 silicone IOLs. The change in BCVA from preoperatively to 1 month postoperatively was equivalent in the 2 lens groups. The BCVA declined from 1 month postoperatively to the last recorded or pre-Nd:YAG visit. This decline was greater in eyes with SI-30/40 silicone IOLs than in those with MA30/60 acrylic IOLs. Although the decrease in BCVA between IOL types was not significantly different, eyes with a SI-30/40 silicone IOL were significantly more likely to develop PCO and have Nd:YAG capsulotomy. Eyes developing PCO had a statistically significant decline in BCVA from 1 month postoperatively to the last/pre-Nd:YAG visit. CONCLUSIONS: The MA30/60 acrylic lenses were associated with lower PCO and Nd:YAG capsulotomy rates than second-generation SI-30/40 silicone IOLs. Patients with MA30/60 IOLs also tended to have less of a decrease in visual acuity than patients with SI-30/40 silicone lenses, probably as a result of the difference in PCO rates between groups.

Acrylic Resins↗

PubMed2002

Ocular malingering: a surprising visual acuity test.

OBJECTIVE: To describe a visual acuity test for use in identifying psychogenic visual impairment and malingering. METHODS: The test contained 32 white plates with a black Landolt C printed in the center. The sequence of the 4 alternative directions of the C was not predictable. After plate 21, 4 circles were interspersed among the remaining plates. The test is administered at a distance from which the subject is presumed to be able to recognize the optotypes. He or she is requested to identify the direction of the C within 2 seconds, and the responses are noted. Two elements were evaluated: (1) The number of correct answers was compared with the corresponding value of the distribution function of the binomial formula that represents the probability of reaching this rate of correct answers by pure chance. (2) The response to the first circle (appearing after plate 21) was compared with the responses to the previous 19 Cs. The test was administered to 20 volunteer pseudomalingerers and 15 patients believed to be true malingerers. RESULTS: Malingering was detected in 14 (74%) of 19 volunteers included in the evaluation and in 12 (80%) of 15 patients by too many or too few correct answers to the stimuli or by their response to one of the circles. CONCLUSIONS: This test is useful in proving malingering. It may also provide evidence of a minimum visual recognition acuity within the gross dimension of the actual acuity.

Adult↗

PubMedDate not supplied

Relationships between visual acuity and anomalous head posture in patients with congenital nystagmus.

PURPOSE: To determine whether patients with congenital nystagmus and an anomalous head posture have better binocular visual acuity than such patients without an anomalous head posture. PATIENTS AND METHODS: This was an observational case series of prospectively collected data for 125 patients with clinical and oculographically confirmed congenital nystagmus. Clinical data were tabulated using computer software. Statistical analyses compared binocular visual acuity with and without the presence of a clinically evident anomalous head posture and visual acuity with and without associated sensory disease. RESULTS: The mean visual acuity was 20/42 (log of the minimal angle of resolution [MAR], 0.32) in patients with an anomalous head posture and 20/83 (logMAR, 0.62) in patients with no anomalous head posture (P < .001). Among patients with disease of the sensory system, those with an anomalous head posture had a mean visual acuity of 20/55 (logMAR, 0.44) and those without an anomalous head posture had a mean visual acuity of 20/108 (logMAR, 0.73; P < .001). CONCLUSIONS: Visual acuity was found to be significantly better in patients with congenital nystagmus who had an anomalous head posture versus those without such a head posture. Our findings indicate that the presence of an anomalous head posture in a patient with congenital nystagmus correlates with good vision and thus may be considered a positive prognostic sign in a preverbal child.

Adolescent↗

PubMed2002

[The state of diopter and visual acuity in central serous chorioretinopathy].

PURPOSE: To investigate the state of diopter and best corrected visual acuity in active central serous chorioretinopathy (CSC). METHODS: Twenty-three unilateral active CSC patients (23 eyes) were observed with Integrated Optometry Apparatus. The period of follow-up was from 3 - 12 months (mean, 7.2 months). RESULTS: Of the 23 patients, 15 eyes (65.2%) of active CSC and 5 fellow eyes (21.7%) showed hyperopic state. There were significant differences in hyperopic state between the active eyes and fellow eyes (P < 0.01). After follow-up, there were only 5 eyes of CSC (21.7%) showed slight hyperopia. There were significant differences in hyperopic state between before and after follow-up of the eyes of CSC (P < 0.01) Among the eyes of the best corrected visual acuities were increased 3 row or above, 90.9% eyes of the best corrected visual acuities were resumed to 1.0. CONCLUSION: Most of the active CSC demonstrated temporary hyperopic state due to the neuroretinal detachment of macula. The best corrected visual acuities with the Integrated Optometry Apparatus in active CSC are useful in evaluating the final visual acuities of the eyes.

Adult↗

PubMed2003

Visual acuity results in school-aged children and adults: Lea Symbols chart versus Bailey-Lovie chart.

PURPOSE: To compare visual acuity results obtained using the Lea Symbols chart with visual acuity results obtained with the Bailey-Lovie chart in school-aged children and adults using a within-subjects comparison of monocular acuity results. METHODS: Subjects were 62 individuals between 4.5 and 60 years of age, recruited from patients seen in five optometry clinics. Each subject had acuity of the right eye and the left eye tested with the Lea Symbols chart and the Bailey-Lovie chart, with order of testing varied across subjects. Outcome measures were monocular logarithm of the minimum angle of resolution (logMAR) visual acuity and inter-eye acuity difference in logMAR units for each test. RESULTS: Correlation between acuity results obtained with the two charts was high. There was no difference in absolute inter-eye acuity difference measured with the two acuity charts. However, on average, Lea Symbols acuity scores were one logMAR line better than Bailey-Lovie acuity scores, and this difference increased with worse visual acuity. CONCLUSIONS: The Lea Symbols chart provides a measure of inter-eye difference that is similar to that obtained with the Bailey-Lovie chart. However, the monocular acuity results obtained with the Lea Symbols chart differ from those obtained with the Bailey-Lovie chart, and the difference is dependent on the individual's absolute level of visual acuity.

Adolescent↗

PubMed1992

Use of 10-Hz flash visual evoked potentials in prediction of final visual acuity in diabetic eyes with vitreous hemorrhage.

In 44 diabetic eyes with vitreous hemorrhage, monocular steady-state visual evoked potentials were elicited through closed eyes by a 10-Hz flash. Visual evoked potentials were rated as normal or abnormal on the basis of amplitude and waveform. Abnormal visual evoked potentials were subdivided into mildly abnormal, markedly abnormal and nonrecordable categories. Patients with normal potentials were predicted to have visual acuities of 6/15 (20/50) or better. Patients with abnormal potentials were predicted to have visual acuities of 6/18 (20/60) or worse. Final visual acuities were the best visual acuities recorded in the 6 months after vitreous surgery (vitrectomy) or spontaneous clearing of the vitreous hemorrhage. The visual evoked potential categories and final acuities were compared with a 2 x 2 contingency table. The accuracy was 86%. The visual evoked potential categories and final acuities were associated at a statistically significant level.

Adult↗

PubMed1996

Magnification and visual acuity in highly myopic phakic eyes corrected with an anterior chamber intraocular lens versus by other methods.

PURPOSE: To calculate retinal magnification and visual acuity in highly myopic phakic eyes corrected with anterior chamber intraocular lenses (IOLs) versus correction by other methods. SETTING: Laboratory of Optics, University of Alicante, Alicante, Spain. METHODS: Relative retinal magnification (RRM) was used to study changes in retinal image size induced by different correcting systems. Relative spectacle magnification (RSM) was used to compare these systems with the emmetropic eye. The matrix method was used to calculate RRM, RSM, and visual acuity in 12 theoretical cases of myopia in eyes with axial lengths from 27.0 to 33.0 mm and corneal powers from 42.00 to 48.00 diopters. RESULTS: The RRM, RSM, and visual acuity increased as corneal power increased for a myopic eye of fixed length. Changing the plane of correction from the spectacle or cornea to the intraocular increased retinal magnification, which increased visual acuity. CONCLUSION: Visual acuity in myopic eyes corrected with an IOL will be better than that in myopic eyes corrected by other means because of the retinal magnification induced by the IOL, which increases visual acuity one line or more.

Anterior Chamber↗

PubMed2000

[Factors influencing visual acuity following vitrectomy for exudative age-related macular degeneration].

PURPOSE: We investigated the influence of various factors on visual results in patients undergoing surgical removal of choroidal neovascular membranes (CNVM) caused by age-related macular degeneration (AMD). SUBJECTS AND METHODS: This study was performed in 55 eyes of 55 patients who underwent surgical removal of CNVM for AMD and followed them for 6 months or more. The criterion for surgical eligibility was active subfoveal choroidal neovascular membrane of 0.5 or more disc diameter above the retinal pigment epithelium with visual acuity of 0.3 or worse. We investigated the influence of various factors on the logarithm of the minimum angle of resolution (log MAR) final visual acuity. The factors were age, symptom duration, preoperative log MAR visual acuity, CNVM diameter, mean deviation with visual field analyzer, previous laser treatment, posterior vitreous detachment, findings of indocyanine green angiography, operative complications, and recurrence of CNVM. RESULTS: Better preoperative visual acuity, shorter symptom duration, and smaller CNVM diameter were correlated with better postoperative final visual acuity. CONCLUSIONS: Surgical excision of subfoveal CNVM may be the better therapeutic choice in selected cases with AMD.

Aged↗

PubMed2006

Prognostic factors for visual acuity improvement after intravitreal triamcinolone injection.

PURPOSE: In some patients with macular oedema, intravitreal triamcinolone acetonide injection (IVTA) fails to improve visual acuity, although oedema shows clinical and angiographic improvement. Side effects can include increased intraocular pressure, cataract development, and (rarely) endophthalmitis. Our purpose was to identify prognostic factors for visual acuity improvement after IVTA. METHODS: Data on patients treated by IVTA for macular oedema were retrospectively reviewed. Three months postinjection, visual acuity was rated as 'improved' (two or more Snellen lines gained) or 'nonimproved' (unchanged or worsened). Comparative demographic data and pre- and post-IVTA clinical and fluorescein angiographic findings were analysed with SPSS software. RESULTS: Of 57 eyes (57 patients), 27 (47%) improved after IVTA. Initial visual acuity ('good', 'moderate', or 'poor') and aetiology of macular oedema (diabetic, venous occlusion, or pseudophakic) did not differ between the two groups. Improvement occurred in significantly more eyes with clinical or angiographic evidence of cystoid macular oedema (CME) than in those with diffuse retinal thickening (P=0.04) or diffuse leakage on fluorescein angiography (P=0.02), respectively, and in significantly more pseudophakic than phakic eyes (P=0.046). CONCLUSIONS: Pseudophakia and clinical or angiographic CME, but not aetiology or initial visual acuity, were prognostic of visual acuity improvement after IVTA for macular oedema.

Adult↗

PubMed1999

Keratoconus with good unaided visual acuities: two case reports.

BACKGROUND: Ophthalmic evaluation of patients with keratoconus (KC) often reveals highly myopic and irregular astigmatic refractive corrections. Irregular corneal astigmatism and central corneal scarring in patients with KC often result in a loss of best-corrected spectacle acuity. Rigid gaspermeable contact lenses generally optimize visual acuities for patients with KC. CASE REPORTS: Two cases are discussed of patients who manifested clinically diagnosed KC but unusually good unaided Snellen visual acuities (20/25+ or better) in both eyes. CONCLUSION: Good unaided visual acuities are not necessarily inconsistent with the diagnosis of KC.

Adult↗

PubMed2002

Visual acuity and the accuracy of the accommodative response.

Previous investigators have observed that some subjects show large amounts of accommodative lag. We hypothesized that less accurate accommodation might be associated with poorer visual acuity and/or smaller pupil sizes. Sixty subjects (30 emmetropes and 30 myopes) aged 20-30 years, participated. All had best-corrected visual acuity of 6/6 or better [mean = -0.10 +/- 0.07 logarithm of the minimum angle of resolution (logMAR)]. Subjects monocularly viewed reduced Bailey-Lovie charts through a +6.50 D Badal lens on a Canon R1 auto-refractor. Visual acuity, accommodative response and pupil diameter were measured for 0, 2 and 4 D accommodative stimuli. For accommodation measurements (N= 10) subjects were instructed to fixate the smallest letters that they could read. The mean accommodative response was +0.22 +/- 0.28, +1.83 +/- 0.23 and +3.71 +/- 0.27 D for the 0, 2 and 4 D stimuli, respectively. The mean visual acuity was -0.06 +/- 0.10, -0.11 +/- 0.07 and -0.11 +/- 0.07 logMAR for the 0, 2 and 4 D stimuli, respectively. Visual acuity for the 0 D stimulus was significantly poorer than for other conditions (p < 0.001) and associated with increased accommodative lead (p < 0.01). There was also an association between visual acuity and accommodative response (or lag) for the 4 D stimulus (p=0.002). The emmetropes showed significantly better visual acuity than the myopes (p= 0.004). No significant difference was observed in the accommodative response between emmetropes and myopes. Pupil diameter was not associated with the accuracy of the accommodative response (p > 0.17). Increased accommodative lead (0 D stimulus) and accommodative lag (4 D stimulus) are associated with decreased visual acuity. Smaller pupil diameters are not associated with increased accommodative lag.

Accommodation, Ocular↗