Axial length changes in highly myopic eyes and influence of myopic macular complications in Japanese adults.

PURPOSE: To investigate changes of the axial length in normal eyes and highly myopic eyes and influence of myopic macular complications in Japanese adults. STUDY DESIGN: Retrospective longitudinal case series. METHODS: The changes in the axial length of 316 eyes from 316 patients (mean age, 63.8 ± 9.0 years; range, 34-82; 240 females) examined using IOLMaster with a follow-up period of at least 1 year were studied. This study included 85 non-highly myopic eyes (|refractive error| ≤ 5 diopters; 63 females; non-highly myopic group), 165 highly myopic eyes (refractive error ≤ -6 diopters or axial length ≥ 26 mm; 124 females) without macular complications (no complications group), 32 eyes (25 females) with myopic traction maculopathy (MTM group), and 34 eyes (28 females) with myopic choroidal neovascularization (CNV group). RESULTS: All groups showed a significant increase in the axial length during the follow-up period (mean follow-up, 28.7 ± 16.8 months; range, 12-78) (P < 0.01). Changes in the axial length/year in the no complications group (0.041 ± 0.05 mm) were significantly greater than those in the non-highly myopic group (0.007 ± 0.02 mm) (P < 0.0001). Furthermore, changes in the CNV group (0.081 ± 0.04 mm) were significantly greater than those in the no complications (P < 0.0001) and MTM (0.040 ± 0.05 mm) (P = 0.0059) groups, whereas no significant difference was found between the changes in the MTM and no complications groups (P = 0.91). Multiple regression analyses indicated that CNV eyes (P < 0.0001) and female patients' eyes (P = 0.04) showed greater changes in the axial length/year. CONCLUSIONS: All groups showed an increase in the axial length, which was greater for highly myopic eyes. In particular, CNV eyes showed greater increases, indicating that larger changes in the axial length may require careful follow-up.

Morphologic characteristics of macular complications of a dome-shaped macula determined by swept-source optical coherence tomography.

PURPOSE: To investigate the morphologic characteristics of macular complications of dome-shaped maculas using swept-source optical coherence tomography (OCT). DESIGN: Retrospective observational case series. METHODS: Axial length measurements and swept-source OCT were performed in 49 highly myopic eyes (in 5 male and 30 female subjects) with dome-shaped maculas. We classified the dome patterns and measured the central retinal thickness, central choroidal thickness, central scleral thickness, and the macular bulge height, and assessed the associations of these parameters with macular complications. RESULTS: The central scleral thickness was significantly negatively correlated with age and the axial length. We classified the eyes into 3 groups: 6 with choroidal neovascularization (CNV group), 8 with retinal pigment epithelial detachment (PED group; 5 with serous retinal detachment), and 35 with no complications (no complications group). Nine eyes had a round dome and 40 had horizontally oriented oval-shaped domes. There were no significant differences in the frequency of macular complications between these patterns. The CNV group was significantly older and had a longer axial length than the other groups. The PED group had significantly larger values for both the central scleral thickness and bulge height than the other groups. The central choroidal thickness was significantly thinner in the CNV group than in the no complications group. CONCLUSION: A dome-shaped macula results from relative thickening of the macular sclera, and this may lead to PED. Thinning of the sclera owing to long-term changes and elongation of the axis may develop CNV and cause visual impairment.

3-D choroidal thickness maps from EDI-OCT in highly myopic eyes.

PURPOSE: Myopic chorioretinal atrophy is a debilitating condition that causes severe loss of primary vision. However, its mechanisms and pathologic course are not well understood. We performed volumetric measurements of the posterior choroid via three-dimensional analysis of the choroid in patients with high myopia to understand its structure, and we compared the measurements with those of normal subjects. METHODS: Twenty-five highly myopic but otherwise normal eyes and 25 nonmyopic eyes were evaluated. Enhanced depth imaging optical coherence tomography (EDI-OCT) was performed using 20 × 20-degree raster scans consisting of 25 high-speed line scans. Three-dimensional retinal and choroidal thickness maps were produced from the EDI-OCT data. For the quantitative analyses, the macula was divided into nine regions, as defined by the Early Treatment Diabetic Retinopathy Study (ETDRS) layout, and the mean retinal and choroidal thicknesses of each region were obtained. RESULTS: The choroidal thicknesses at all regions in the high-myopia group were significantly smaller than those in the normal refractive group (p < 0.0001). The foveal choroidal thickness was the greatest in the normal group but not in the high-myopia group. In the high-myopia group, the choroidal thickness at the fovea was significantly greater than that at the outer nasal quadrants (p < 0.0001) but significantly smaller than that at the outer superior (p < 0.0001) quadrants. CONCLUSIONS: Three-dimensional choroidal thickness maps obtained via EDI-OCT are useful for quantifying choroid thickness in subjects with high myopia more accurately.