RESUMO
A patient with Aicardi syndrome is presented. We report results of DNA analysis from the patient and her parents with probes mapped to Xp21.3-22.3 in an attempt to localize a deletion in this region. No signs of a microdeletion could be detected, using 5 different DNA markers. Further, it is suggested that a specific combination of cerebral abnormalities may be characteristic of the syndrome and that antenatal ultrasonographic diagnosis may be feasible.
Assuntos
Agenesia do Corpo Caloso , Cromossomos Humanos Par 21/ultraestrutura , Cromossomos Humanos Par 22/ultraestrutura , DNA/análise , Anormalidades do Olho/genética , Espasmos Infantis/genética , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Mapeamento Cromossômico , Corpo Caloso/diagnóstico por imagem , Anormalidades do Olho/diagnóstico por imagem , Feminino , Marcadores Genéticos , Humanos , Recém-Nascido , Cintilografia , Espasmos Infantis/diagnóstico por imagem , Síndrome , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
Visual evoked cortical potentials (VECP) were recorded from 10 subjects with normal visual acuity (VA) 1.0. Reversing square-wave gratings of 16 different spatial frequencies were used as stimuli. In all 10 subjects significant increase in power at the stimulation frequency was observed in the Fourier spectrum. The VA, calculated from the Fourier spectra, ranged from 0.4 to 1.0. The described method for VA measurement is entirely objective, and the examination can be performed very rapidly and conveniently with the aid of a computer. However, the results indicate that the reliability of the measurement in individual cases may be doubtful.
Assuntos
Potenciais Evocados Visuais , Acuidade Visual , Adulto , Humanos , Métodos , Estimulação LuminosaRESUMO
Divergent contrast sensitivity findings have been reported in patients with intraocular lens implants. In this study, contrast sensitivity to stationary sine-wave gratings of six spatial frequencies from 0.5 to 22.8 cycles/degree was measured psychophysically in 13 patients with posterior chamber intraocular lens implants and in 10 controls. Corrected visual acuity was 0.7 to 1.0 in the intraocular lens group and 0.9 to 1.0 in the reference group. The age, the pupil diameter and the rate of subtle age-related macular changes were equal in the two groups. No statistically significant difference in mean contrast sensitivity between the patients and the controls was observed at any spatial frequency examined.
Assuntos
Sensibilidades de Contraste , Lentes Intraoculares , Fatores Etários , Idoso , Feminino , Humanos , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Acuidade VisualRESUMO
Seventy-one children, age 4-12 years, with subnormal visual acuity (VA) in at least one eye (0.7 or less) were examined using visual evoked cortical potentials (VECPs) to pattern-reversal stimulation. Twenty-eight children with squint had mean VA 0.3 in squinting and 0.7 in non-squinting eyes. Thirty-one children had unexplained subnormal VA, mean 0.6. Twelve children with mild unclassifiable fundus abnormalities had mean VA 0.5. In the squinting eyes and the eyes with fundus abnormalities the mean latency of the VECP was significantly prolonged. In squinters the mean amplitude to stimulation of the squinting eyes and to binocular stimulation was significantly reduced. Statistically significant increase in the mean VA was observed in all groups except in the cases with visible fundus abnormalities. There was no statistically significant correlation between VECP parameters and final VA. In conclusion, VA prognosis could not be predicted from VECP data in individual cases.