Biomedical subjects

Solange R Salomão

Publications and source records attributed to Solange R Salomão.

5 recordsLinked to original sources

PubMed2005

Chromatic and luminance contrast sensitivities in asymptomatic carriers from a large Brazilian pedigree of 11778 Leber hereditary optic neuropathy.

PURPOSE: To determine whether asymptomatic 11778 LHON carriers demonstrated impairments in (1) chromatic red/green (R/G) and blue/yellow (B/Y) contrast sensitivity functions (CSF) and in (2) luminance contrast sensitivity functions in the spatial CSF (SCSF) and temporal CSF (TCSF) domains. METHODS: Twenty-five carriers (8 male, 17 female; 34.1 +/- 15.1 years of age) of homoplasmic 11778 LHON from the same well-described family and 30 age-matched controls (17 male, 13 female; 29.2 +/- 7.1 years of age) were tested in one eye, randomly selected. Of the 25 eyes tested, 18 had normal fundus, 5 had swelling and microangiopathy, and 2 had temporal pallor. The R/G and B/Y CSFs were obtained after equiluminance correction with bichromatic horizontal sinusoidal gratings at 0.3, 0.7, and 2 cycles per degree (cpd); the SCSFs were obtained with achromatic gratings at 0.3, 2, 6, and 12 cpd; and the TCSFs were obtained at 2, 10, 20, and 33 Hz with sinusoidal modulation of a 2.7 degrees field with a superimposed spatial Gabor function. RESULTS: Differences between carriers and controls were statistically significant for all spatial frequencies of chromatic and luminance SCSFs, but not for the TCSFs. R/G equiluminance settings of carriers differed from those of controls (P < 0.001), requiring higher luminance in the green; B/Y equiluminance settings were not statistically different in carriers and controls. Fundus findings did not correlate with CS results. CONCLUSIONS: Luminance and chromatic spatial CS losses that affected all tested spatial frequencies, are reported in LHON asymptomatic carriers with the mtDNA 11778 mutation. No losses were found in the temporal CSF. An intriguing finding is that the blue system is substantially spared in this LHON family. These represent subclinical visual impairments in otherwise asymptomatic LHON carriers.

Adolescent↗

PubMed2004

Development of an instrument to assess vision-related quality of life in young children.

PURPOSE: Quality of life (QOL) instruments are increasingly utilized in ophthalmological research. Measuring vision-related QOL in young children is complicated by constantly evolving abilities related to normal growth and development. Our aim was to develop vision-related QOL instruments for children in different age ranges <==7 years, and to provide initial validation of these instruments. DESIGN: Cross-sectional study. METHODS SETTING: Multicenter. PATIENTS: 773 pediatric patients (age <==7 years) with a wide range of ophthalmological diagnoses. PROCEDURE: Questionnaire. A 61-item prototype instrument with a wide variety of items was applied to 403 consecutive patients. The usefulness of items was evaluated as a function of age in order to derive two age-group specific instruments and to find the age limit dividing the age groups. Thus, age-specific versions of a Children's Visual Function Questionnaire (CVFQ) were defined for ages <3 years and >/=3 years, and applied to a convenience sample of patients. OUTCOME: Subscale scores. Factor analysis helped identify underlying dimensions of the data, and corresponding subscales were defined. Validation was provided by examining the internal consistency reliability and by exploring the associations between scores and clinical characteristics. RESULTS: Subscales for General health, General vision, Competence, Personality, Family impact, and Treatment were defined, with internal consistency reliabilities ranging from 0.60 to 0.86. The association between subscales scores and age was weak, whereas strong correlations were found with the level of visual impairment and type of visual diagnosis. CONCLUSION: The CVFQ assesses the impact of visual impairment on children and their families, and is expected to become a useful tool for the pediatric vision research community.

Child↗

PubMed2004

Visual electrophysiologic findings in patients from an extensive Brazilian family with Leber's hereditary optic neuropathy.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited disease, associated with mitochondrial DNA (mtDNA) point mutations and characterized by bilateral, usually sequential, rapid loss of central vision. The purpose of this study was to investigate electrophysiologically a small cohort of members from an extensive Brazilian family affected by LHON. Pattern-reversal visual evoked potentials (PVEP), and full-field electroretinograms (ERG) were performed on the four index members, all carrying the 11778 homoplasmic mtDNA mutation. They were a 14-year-old recently affected male, his unaffected mother, and her two affected brothers. The three affected members all had bilateral profound visual loss with visual acuities that ranged from 20/250 to CF, cecocentral defects, and severe dyschromatopsia (by FM-100). The unaffected (carrier) female had normal visual acuities, visual fields and color discrimination. Severely prolonged P100 latencies and decreased N75-P100 peak amplitudes were found in pattern-reversal VEPs for three affected members. Normal PVEP responses were found in the carrier female. Rod and cone ERG responses were normal in two affected members, but both the carrier mother and her affected son showed reduced peak-to-peak amplitude for single-flash cone response and 30 Hz flicker, with normal b-wave implicit times. Thus, optic nerve function, evaluated by PVEP, was severely reduced in LHON affected members and normal in the carrier female. However, reduced ERG cone responses suggest that LHON can also affect retinal elements, even in the absence of fundus and other clinical changes that constitute the full and classical expression of LHON.

Adolescent↗

PubMed2002

Preschool Worth 4-Shape test: testability, reliability, and validity.

PURPOSE: The Worth 4-Dot is used to assess binocular fusion, but it is difficult to use with young children. We modified the Worth 4-Dot by replacing the circles with shapes while maintaining the same color configuration. The purpose of this study was to determine the testability, reliability, and validity of the Worth 4-Shape test. METHODS: Subjects aged 2 to 8 years and 4 patients aged over 8 years with best-corrected visual acuity of 20/40 or greater (n = 131 patients, n = 123 normals) attempted test and retest at 35 cm and 3m using the Worth 4-Shape and Worth 4-Dot. To provide a gold standard, medical history, bifoveal fixation, and stereoacuity were reviewed. RESULTS: Testability of the Worth 4-Shape was significantly higher than the Worth 4-Dot both in children aged less than 4 years (95.9% vs 79.5% at 35 cm, P <.001; 79.5% vs 55.1% at 3 m, P <.001) and older than 4 years (98.5% vs 88.6% at 35 cm, P <.001; 90.9% vs 82.4% at 3m, P =.04). Test-retest analysis found comparable concordance for the Worth 4-Shape and Worth 4-Dot tests (P >.3). The sensitivity and specificity of the Worth 4-Shape (92%, 97%) and Worth 4-Dot (90%, 94%) were comparable. Between-test analysis found 96% agreement between both tests at 35 cm and 97% agreement at 3m. CONCLUSIONS: The success rate for the Worth 4-Shape is higher than the Worth 4-Dot, especially in children aged less than 4 years, and has equivalent accuracy. The Worth 4-Shape test-retest reliability is high supporting its validity for use with young children.

Child↗

PubMedDate not supplied

Multifocal and full-field electroretinogram changes associated with color-vision loss in mercury vapor exposure.

We evaluated the color vision of mercury-contaminated patients and investigated possible retinal origins of losses using electroretinography. Participants were retired workers from a fluorescent lamp industry diagnosed with mercury contamination (n = 43) and age-matched controls (n = 21). Color discrimination was assessed with the Cambridge Colour Test (CCT). Retinal function was evaluated by using the ISCEV protocol for full-field electroretinography (full-field ERG), as well as by means of multifocal electroretinography (mfERG). Color-vision losses assessed by the CCT consisted of higher color-discrimination thresholds along the protan, deutan, and tritan axes and significantly larger discrimination ellipses in mercury-exposed patients compared to controls. Full-field ERG amplitudes from patients were smaller than those of the controls for the scotopic response b-wave, maximum response, sum of oscillatory potentials (OPs), 30-Hz flicker response, and light-adapted cone response. OP amplitudes measured in patients were smaller than those of controls for O2 and O3. Multifocal ERGs recorded from ten randomly selected patients showed smaller N1-P1 amplitudes and longer latencies throughout the 25-deg central field. Full-field ERGs showed that scotopic, photopic, peripheral, and midperipheral retinal functions were affected, and the mfERGs indicated that central retinal function was also significantly depressed. To our knowledge, this is the first demonstration of retinal involvement in visual losses caused by mercury toxicity.

Adult↗