Myopia is a highly frequent ocular disorder worldwide and pathologic myopia is the 4th most common cause of irreversible blindness in developed countries. Pathologic myopia is especially common in East Asian countries. Ocular alterations associated with pathologic myopia, especially those involving the macular area-defined as myopic maculopathy-are the leading causes of vision loss in patients with pathologic myopia. High myopia is defined as the presence of a highly negative refractive error (>-6 to -8 diopters) in the context of eye elongation (26-26.5 mm). Although the terms high myopia and pathologic myopia are often used interchangeably, they do not refer to the same eye disease. The two key factors driving the development of pathologic myopia are: 1) elongation of the axial length and 2) posterior staphyloma. The presence of posterior staphyloma, which is the most common finding in patients with pathologic myopia, is the key differentiating factor between high and pathologic myopia. The occurrence of staphyloma will, in most cases, eventually lead to other conditions such as atrophic, traction, or neovascular maculopathy. Posterior staphyloma is for instance, responsible for the differences between a myopic macular hole (MH)-with and without retinal detachment-and idiopathic MH. Posterior staphyloma typically induces retinal layer splitting, leading to foveoschisis in myopic MH, an important differentiating factor between myopic and emmetropic MH. Myopic maculopathy is a highly complex disease and current classification systems do not fully account for the numerous changes that occur in the macula of these patients. Therefore, a more comprehensive classification system is needed, for several important reasons. First, to more precisely define the disease stage to improve follow-up by enabling clinicians to more accurately monitor changes over time, which is essential given the progressive nature of this condition. Second, unification of the currently-available classification systems would establish standardized classification criteria that could be used to compare the findings from international multicentric studies. Finally, a more comprehensive classification system could help to improve our understanding of the genetic origins of this disease, which is clearly relevant given the interchangeable-but erroneous-use of the terms high and pathologic myopia in genetic research.

Purpose. To evaluate choroidal thickness in healthy pediatric population by swept-source longer-wavelength optical coherence tomography (SS-OCT). Methods. This was a cross-sectional comparative, noninterventional study. The macular area of 83 eyes from 43 pediatric patients (<18 years) was studied with an SS-OCT prototype system. Macular choroidal thickness was manually determined at 750-μm intervals by measuring the perpendicular distance from the posterior edge of the RPE to the choroid/sclera junction, along a horizontal 4500-μm line centered in the fovea. Three observers independently determined choroidal thickness. Pediatric choroidal thickness was compared with choroidal thickness from 75 eyes from 50 normal healthy adult volunteers (18 years or older). Results. Mean age was 10 ± 3 years (3–17) in the pediatric population versus 53 ± 16 (25–85) in the adult population (P < 0.001). Mean spherical equivalent was not different (P = 0.06) between both groups. Mean subfoveal choroidal thickness was 312.9 ± 65.3 μm in the pediatric versus 305.6 ± 102.6 μm in the adult population (P = 0.19). Mean macular choroidal thickness was 285.2 ± 56.7 μm in the pediatric versus 275.2 ± 92.7 μm in the adult population (P = 0.08). The distribution of choroidal thickness along the horizontal line was different for both populations; the temporal choroid was thicker in the pediatric population (320, 322, and 324 μm; P = 0.002, 0.001, and 0.06, respectively), followed by the subfoveal (312 μm) and nasal choroid (281, 239, and 195 μm). Conclusions. Macular choroidal thickness in the pediatric population is not significantly thicker than that of healthy adults. Differences are more remarkable in the temporal side of the fovea.

To determine choroidal thickness (CT) profile in a healthy population using swept-source optical coherence tomography (SS-OCT). This was a cross-sectional, noninterventional study. A total of 276 eyes (spherical equivalent ± 3 diopters [D]) were scanned with SS-OCT. Horizontal CT profile of the macula was created measuring subfoveal choroidal thickness (SFCT) from the posterior edge of retinal pigment epithelium (RPE) to the choroid-sclera junction. Three determinations were performed at successive points 1000 μm nasal and five more temporal to the fovea. Subjects were divided into five age groups. The mean SFCT was 301.89 ± 80.53 μm (95% confidence interval: 292.34-311.43). The mean horizontal macular choroidal thickness (MCT) was 258.69 ± 64.59 μm (95% confidence interval: 251.04-266.35). No difference in CT was found between men and women. Mean SFCT of the different study groups was 325.6 ± 51.1 (0-10 years), 316.7 ± 90.1 (11-20 years), 313.9 ± 80.3 (21-40 years), 264.6 ± 79.3 (41-60 years), and 276.3 ± 88.8 μm in subjects older than 60 years (P < 0.001; ANOVA test). Mean horizontal MCT was 286.0 ± 43.5, 277.7 ± 68.2, 264.0 ± 61.9, 223.4 ± 62.2, and 229.7 ± 66.1 μm, respectively (P < 0.001; ANOVA test). The CT profile was different for each age group. To our knowledge, this is the first population study of CT of healthy eyes across a broad range of age groups using SS-OCT. As has been determined using spectral-domain OCT, CT decreases with advancing age, especially after age 40. There were no differences due to sex. The greatest CT variation takes place in temporal sectors.

Background/aims To correlate visual acuity in highly myopic eyes without macular disease with retinal and choroidal thickness as measured by spectral-domain optical coherence tomography (OCT). Methods 60 eyes of 46 highly myopic patients (spherical equivalent ≥−6 D or axial length ≥26 mm) were studied in a clinical setting. Eyes with any clinical evidence of maculopathy or amblyopia were excluded. Eyes were imaged using the 3D-2000 OCT (Topcon Corporation, Tokyo, Japan). Two independent investigators manually measured: choroidal thickness at 500-μm intervals up to 2500-μm nasal and temporal to the fovea, subfoveal choroidal thickness, foveal thickness, outer nuclear layer and photoreceptors in addition to retinal pigment epithelium (RPE). Statistical analysis was performed. Results Mean age was 45.9±17.9 years (range 18–99), mean best-corrected visual acuity (BCVA) LogMAR was 0.11±0.19 (range 0–1), mean axial length was 28.2±2.4 mm (range 26–35.3) and mean spherical equivalent was −12.05±5.02 D (range −6 to −26). Mean macular choroidal thickness was 157±84.6 μm (range 16.7–426.5), mean subfoveal choroidal thickness was 166±88.7 μm (range 13.5–486.5), mean foveal thickness was 221.1±30.3 μm (range 157.5–296), mean outer nuclear layer was 121.3±22.6 μm (range 74–191.5) and mean photoreceptors in addition to RPE was 99.5±10.8 μm (range 71.5–115.5). BCVA (LogMAR) negatively correlated with macular choroidal thickness (r=−0.371, p=0.003), subfoveal choroidal thickness (r=−0.358, p=0.004) and photoreceptors and RPE aggregate (r=−0.346, p=0.006). Conclusions Subfoveal choroidal thickness, mean macular choroidal thickness and outer retinal thickness are the most important predictive factors of visual acuity in highly myopic eyes without macular pathology. Outer nuclear layer and foveal thickness are not related to visual acuity.

Purpose: To analyze the vascular density of the choroid in a healthy population using swept-source optical coherence tomography. Methods: A cross-sectional, noninterventional study. Inclusion criteria: best-corrected visual acuity between 20/20 and 20/25, spherical equivalent between ±3 diopters, no systemic or ocular diseases, and ages ranging between 3 and 85 years. One hundred and thirty-six eyes from 136 subjects were analyzed, 86 eyes (63.2%) were from male and 50 eyes (36.8%) from female subjects. The eyes were divided into different age groups to analyze the possible age-related changes. Twelve-millimeter horizontal, fovea-centered B-scans were used. Choroidal stroma and vessel area analysis involved automated segmentation and binarization using validated algorithms. Results: Mean age was 33.1 ± 24.5 years. Mean choroidal area was 0.5554 ± 0.1377 mm². Mean stromal area was 0.2524 ± 0.0762 mm², and mean vascular region area was 0.3029 ± 0.0893 mm². The percentage of choroidal vascularity (vascular area/total area) was 54.40 ± 8.35%. Choroid area, vascular region, and percentage of choroidal vascular density were statistically higher in the 18-year-old group (P < 0.001). The stromal region was not different (P = 0.46). In the same way, choroid area, vascular region, and percentage of choroidal vascular density between the 5 age groups were statistically different (P < 0.001), showing larger figures in the 0 to 10-year-old group, but not stromal region (P = 0.71). There were no gender-related differences. Conclusion: The luminal area and the percentage of vascular/total area decrease with increasing age, while the stromal area remains stable.