ObjectivesTo evaluate the reproducibility of Heidelberg retina tomograph (HRT) macular edema module(MEM) measuring the macular retinal thickness.MethodsSixty-two healthy volunteers (9-68 years old) were examined by HRT-II procedure. The retinal signal width (SW) at macula and fovea and macular edema index (E) were recorded for t-test, Pearson linear-correlation analysis. Intra-subject variation repeatedly measured was analyzed with coefficient of variation, 95% tolerance limits of change (TC), and intraclass coefficient of correlation (ICC). ResultsIn healthy individuals, retinal SW was (0.734±0.236) mm at macula，and (0.781±0.243) mm at fovea; macular E was (1.169±0.619). The coefficient of variation repeatedly measured: retinal SW was (8.7±68)%，retinal SW at the fovea was (8.5±6.7)%, and the average was (15.6±13.9)%; 95%TC of intra-subject sequential repeated measurement was 0.131 (8.9%) of retinal SW, 0.137 (10.5%)of fovea SW，and 0.198 (7.4%) of average E. ICC of one individual repeatedly measured by one operator was 0.950 of macular SW, 0.949 of fovea SW, and 0.898 of average edema index.ConclusionsHRT-II MEM is noninvasive, fast and highly reproducible, which provides a new technique to monitor the objective quantification of macular diseases related to retinal thickness. ( Chin J Ocul Fundus Dis, 2005,21:103-105)
ObjectiveTo observe the macular morphological development and thickness of retinal layers in infants. MethodsFifty-eight infants (86 eyes) were randomly selected from neonatal intensive care unit. They were divided into 4 groups according to the corrected gestational age, including <32 weeks group (10 cases, 14 eyes), 33 to 36 weeks group (26 cases, 39 eyes), 37 to 41 weeks group (12 patients, 18 eyes) and ≥42 weeks group (10 cases,15 eyes). Twelve health adults (22 eyes) were randomly selected as adult group. All infants and adults underwent a portable optical coherence tomography (OCT) examination, focus on the macular morphology. The thickness of 9 retinal layers at fovea and parafovea (750 μm, 1500 μm from central fovea) were measured, including retinal neurepithelium layer, the inner retina, the outer retina, nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer and inner nuclear layer. The correlation between retinal thickness and corrected gestational age was analyzed. ResultsMacular fovea was shallow in early infancy, and then form a mature macular fovea finally with corrected gestational age. The outer retina structure was more mature than the inner retina of infants. With the increase of the corrected gestational age, the following structures gradually developed including the outer limiting membrane (OLM), the junction of inner and outer segment of photoreceptor (IS/OS), the outer segment of photoreceptor/retinal pigment epithelium layer (OS/RPE). The earliest corrected gestational age to detect the OLM, IS/OS, OS/RPE was 32+6, 35, 47+6 weeks respectively. The RPE and choroid layer became thicker gradually. There were no statistical differences between infants group and adults group (P>0.01) for the following thickness measurements, including inner retina at 750 μm parafovea, nerve fiber layer at 1500 μm parafovea, ganglion cell layer at central fovea and parafovea (750 μm, 1500 μm). The thickness of other retinal layers was different between different sites, between different corrected gestational ages, and between infants and adults groups (P<0.01). Correlation analysis found that, except of retinal ganglion cell layer, the thickness of other retinal layers was correlated with the corrected gestational age (P<0.05). ConclusionsMacular fovea is shallow in early infancy, and then form a mature macular fovea finally with corrected gestational age. At infant's early stage, the outer retina of macular is gradually thickening, of which the most obvious variation are the inner nuclear layer and outer nuclear layer. But the development speed of all layers is inconformity.
ObjectiveTo evaluate the repeatability and reproducibility of macular ganglion cell-inner plexiform layer (GCIPL) thickness measurement using spectral-domain optical coherence tomography (Cirrus HD-OCT). MethodOne hundred and eight eyes of 54 normal subjects (26 males and 28 females) between 19 and 75 years of age were included. Each eye underwent macular scanning using Cirrus HD-OCT Macular Cube 512×128 protocol by two operators. Three scans of each eye were obtained by each operator. For the right eye of each subject, three extra scans were obtained using Macular Cube 200×200 protocol by one operator. The average, minimum, superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal GCIPL thickness was analyzed and the repeatability of GCIPL thickness measurement was evaluated with intra-operator, inter-operator, intra-protocol, and inter-protocol intraclass correlation coefficients (ICC). Ten extra scans were obtained from the left eyes of 10 randomly selected subjects for reproducibility assessment with coefficients of variation (CV). ResultsThe intra-operator ICC of macular GCIPL measurement using Macular Cube 512×128 protocol by two operators were 0.959-0.995 and 0.954-0.997, respectively; and the inter-operator ICC were 0.944-0.993. All intra-and inter-operator ICC were > 0.800 with the highest and lowest records of the average and minimum GCIPL thickness, respectively. The intra-protocol ICC of Macular Cube 512×128 protocol and Macular Cube 200×200 protocol were 0.986-0.996 and 0.927-0.997, respectively; and the inter-protocol ICC were 0.966-0.994. All intra-and inter-protocol ICC were > 0.800. CV of GCIPL thickness measurement using Macular Cube 512×128 protocol were (0.70±0.31)%-(1.35±0.86)%. ConclusionCirrus HD-OCT can measure macular GCIPL thickness in normal eyes with excellent repeatability and reproducibility.