RESUMO
Stargardt disease (STGD) is an inherited genetic eye condition involving bilateral macular dystrophy leading to progressive central vision loss. It is the most common form of autosomal recessive juvenile macular dystrophy. In this study, ELOVL4 and PRPH2 genes were analyzed in 30 STGD probands for genetic variations using next-generation sequencing. In the patient group, two genetic variants in exon 6 of ELOVL4, and three in exon 3 of PRPH2 were detected. All sequence modifications in both ELOVL4 and PRPH2 were recorded, including those of a non-pathogenic nature. In the control group, four different genetic variations were detected in ELOVL4, and five in PRPH2. STGD patients of different ethnicities may carry distinct ELOVL4 and PRPH2 sequence variants. We believe that the genetic variations identified in this study may be related to STGD etiopathogenesis.
Assuntos
Proteínas do Olho/genética , Degeneração Macular/congênito , Proteínas de Membrana/genética , Periferinas/genética , Éxons/genética , Feminino , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Degeneração Macular/genética , Degeneração Macular/patologia , Masculino , Mutação , Linhagem , Doença de Stargardt , TurquiaRESUMO
This study reports tympanic cavity (TC) volume in newborns, which was missing in the literature. Ex vivo histology and computerized tomography (CT) scans were performed on temporal bone and data were analyzed in part using software developed in house. CT images with a slice thickness of 0.5 mm were obtained from 5 newborn cadavers and analyzed independently by two expert researchers. The border of the TC was delineated manually and measurement of area of interest was calculated on masked images. Then, the area measurements from all sections were added to estimate the total volume. The agreements between the histological and CT findings were then compared for accuracy, repeatability and reliability. The Dice and Jaccard similarity coefficient measures were used as a statistical validation metric to evaluate the assessor's performance in manual volume segmentation. Good assessor agreement was observed with average Dice values above 0.8 indicating that consistent and reliable volume measurements were feasible. The proposed protocol was shown to be accurate in calculating the TC volume, and thus can be used for computer-assisted presurgical planning or for diagnosing structural alterations in TC.
El objetivo fue determinar el volumen de la cavidad timpánica (CT) en recién nacidos, información no encontrada en la literatura. Se realizaron escaners a través de tomografia computadorizada (TC) y estudios histológicos en el hueso temporal; los datos se analizaron utilizando un software desarrollado en nuestra institución. Se obtuvieron imágenes de secciones de TC, de 0,5 mm de grosor, a partir de 5 cadáveres de recién nacidos, los que fueron analizados de forma independiente por dos investigadores expertos. El margen de los cortes de TC fue delineado manualmente y la medición del área de interés se estimó sobre imágenes ocultas. Después, se añadieron las mediciones de área de todas las secciones para estimar el volumen total. Las concordancias entre el estudio histológico y los hallazgos de la TC se compararon en cuanto a precisión, repetibilidad y confiabilidad. Se utilizaron las medidas de coeficiente de similitud de Jaccard y Dice como métrica de validación estadística para evaluar el desempeño del asesor en la medición manual del volumen. Se observó una buena correlación del evaluador con los valores medios de Dice, por encima de 0,8 indicando que es factible obtener mediciones coherentes y confiables de volumen. El protocolo propuesto ha demostrado ser preciso para calcular el volumen de la CT, y por lo tanto se puede utilizar para la planificación prequirúrgica asistida o para el diagnóstico de alteraciones estructurales en la CT.