Normative database and determinants of macular vessel density measured by optical coherence tomography angiography.

IMPORTANCE: To provide a normative vessel density (VD) database for the macula through swept-source optical coherence tomography angiography (OCTA) and to assess the main determinants of this measurement. BACKGROUND: In contrast with dye angiography, the recently introduced OCTA technique allows for the non-invasive measurement of retinal and choroidal VD metrics. DESIGN: Cross-sectional study. PARTICIPANTS: The right eyes of 346 healthy subjects were studied. In 105 subjects both eyes were imaged. METHODS: Foveal and parafoveal macular VD measurements were obtained in the retinal superficial capillary plexus (SCP), deep capillary plexus (DCP), and in the choriocapillaris (CC) layer. Also recorded were age, sex, axial length (AL), foveal and choroidal thickness (CT). MAIN OUTCOME MEASURES: Normative database and determinants of macular VD measured by OCTA. RESULTS: Mean participant age was 38.3 ± 20.1 years (mean ± SD) (range 5-83). Foveal VDs in the different plexuses were: SCP 22.1% ± 5.0% (7.3-35.1), DCP 19.9% ± 6.3% (6.9-51.2) and CC: 52.8% ± 4.3% (40.2-62.1). Parafoveal VDs ranged from 45.4% ± 3.7% to 51.8% ± 4.6%. Positive correlation was observed between foveal VD and foveal thickness (R = .327), as well as between parafoveal DCP VD and CT (R = .250;P ≤ .006), while correlation with age was negative in the SCP and CC (R = -.283;P < .001). No associations were detected between macular VD and sex or AL (P ≥ .05). CONCLUSION AND RELEVANCE: Macular VD showed wide individual variation, was positively correlated with foveal thickness and with CT, negatively correlated with age, and showed no correlation with AL or sex.

Normative Pentacam anterior and posterior corneal elevation measurements: effects of age, sex, axial length and white-to-white.

PURPOSE: To provide normal corneal elevation data for a large Caucasian population and to determine the impacts on these data of age, sex, axial length (AXL) and horizontal white-to-white (WW). SETTING: Centro Internacional de Oftalmología Avanzada, Madrid, Spain. DESIGN: Retrospective, cross-sectional, observational. METHODS: In this retrospective, cross-sectional, observational study, anterior and posterior corneal elevations were measured in 789 right eyes of subjects with no ocular disease at the thinnest corneal location in relation to a fixed 8-mm best-fit sphere using the Pentacam, and AXL and WW were measured with the IOLMaster. A multiple linear regression model was used to assess the effects of age, sex, AXL and WW on the elevation data. RESULTS: Mean subject age was 50.5 ± 15 years (range 17-93 years); 64% were women. Mean anterior and posterior corneal elevations were 1.99 ± 1.75 µm (- 7 to 10 µm) and 7.70 ± 5.7 µm (- 6 to 28 µm). Anterior corneal elevations were higher by 0.165 µm and 0.033 µm for every mm reduction in AXL and every year reduction in age, respectively. Sex and WW were not significant predictors of anterior elevations (R2 = 7.7%). Posterior corneal elevation increased by 0.186 µm/year of age, 0.707 µm/mm reduction in WW and 0.819 µm/mm reduction in AXL. This variable was also 0.866 µm greater in men (R2 = 34.4%). CONCLUSION: Anterior corneal elevations decrease with age and are higher for shorter AXL but are not influenced by sex or WW. Posterior corneal elevations increase with age, decreasing AXL, decreasing WW and are higher in men.

Anterior Chamber Angle Tissue as an Incidental Optical Coherence Tomography Finding in a Large Healthy Caucasian Child Population.

PURPOSE: The aim of this study was to describe the presence of anterior chamber angle (ACA) tissue as an incidental optical coherence tomography (OCT) finding in healthy children. METHODS: For this cross-sectional study, we reviewed Fourier-domain OCT images obtained in 422 children, who were chosen as candidates for inclusion in a prior study, and who visited our clinic for a routine vision test. The presence of angle tissue was assessed in the nasal and temporal quadrants. On tomographies showing angle tissue, several measurements were made, including ACA width and trabecular meshwork length and size. RESULTS: Hyperreflective tissue was observed in the ACA recess in 14 eyes of 13 children subjected to OCT (3.3%). This tissue was only present in 1 quadrant. The mean age of the affected children was 10.1±2.5 years (range, 7 to 14); 69% were female patients. Spherical refractive error was -0.5 to +1.75 D. ACA width was 45.9±9.1 (24.8 to 57.9) in the nasal quadrant and 44.3±10.1 (23.9 to 60.1) in the temporal quadrant. Trabecular meshwork length and size were 494±94 µm (322 to 732) and 0.064±0.018 mm (0.03 to 0.11), respectively. In all 13 children, intraocular pressure was ≤18 mm Hg, the appearance of the optic nerve head was normal, and none had a family history of glaucoma. CONCLUSIONS: We, here, report the incidental observation of angle tissue in a small percentage of healthy Caucasian children. The follow-up of these children in future work could clarify the possible clinical implications of this observation.

Anterior Chamber Angle and Trabecular Meshwork Measurements Made by Fourier-domain Optical Coherence Tomography in Healthy White Children.

PURPOSE: To obtain anterior chamber angle and trabecular meshwork (TM) measurements by Fourier-domain optical coherence tomography (FD-OCT) in a population of healthy white children. MATERIALS AND METHODS: This was a cross-sectional study examining 409 right eyes of 409 children. Trabecular-iris angle (TIA) and TM length and area were measured by FD-OCT (RTVue 100) in the nasal and temporal quadrants to analyze correlations between angle or TM measurements and age, sex, and refractive error. RESULTS: Mean participant age was 10.5±3.4 years (range, 3 to 18 y); 51% were boys. Mean spherical error was 0.56±2.4 D (range, -9 to +7.5 D). TIA could be measured in 99%, whereas TM measurements could only be made in 83%. Mean TIA was 43.1±10.0 degrees (range, 16 to 76 degrees). No differences were observed in angle width according to sex (P=0.299; t test). TIA was correlated with age (R=0.204; P<0.001) and with spherical error (R=-0.457; P<0.001). Mean TM length was 530±106 µm (range, 299 to 891 µm) and mean TM area was 0.065±0.021 mm (range, 0.030 to 0.180 mm). No correlation was observed between TM metrics and age, sex or refractive error (R<0.08; P≥0.172). CONCLUSIONS: FD-OCT proved useful for the noninvasive measurement of TIA and TM metrics in children. Spherical error was the main determinant of TIA.

Morphometry of the trabecular meshwork in vivo in a healthy population using fourier-domain optical coherence tomography.

PURPOSE: We measured the length, thickness, and area of the trabecular meshwork (TM) in vivo using Fourier domain optical coherence tomography (FD-OCT) in a Caucasian population of healthy subjects. METHODS: A cross-sectional study was done of 1006 healthy subjects. Left eyes were randomly selected. Age, sex, IOP, and spherical refractive error were noted. The depth and volume of the anterior chamber and the central corneal thickness were measured with Pentacam, while IOL Master was used to measure the axial length. The length, thickness, and area of the TM were measured through FD-OCT RTVue. A study was done to determine the correlation between TM size, and other demographic and ocular parameters. Finally, the reproducibility of the measurements was assessed for a subgroup of 50 eyes from 50 patients. RESULTS: We were able to measure the TM in 91.1% of the total eyes studied. The mean TM length was 496.99 ± 92.77 µm (range, 275-800), TM thickness was 174.16 ± 28.14 µm (range, 100-276), and TM area was 0.069 ± 0.031 mm(2) (range, 0.023-0.133). No differences were found in terms of length and area for sex, although the TM was slightly thicker in men (P = 0.046). No correlation was observed between the TM measurements and any of the studied demographic or ocular parameters (R < 0.09, P < 0.001). Intra- and interobserver reproducibility of the measurements were good (intraclass correlation coefficient > 0.750, P < 0.001). CONCLUSIONS: The FD-OCT is an effective and reproducible examination technique to measure the length, thickness, and area of the TM in vivo.