PURPOSE: To characterize the changes occurring in choroidal thickness (ChT) across the posterior pole during accommodation using enhanced-depth imaging optical coherence tomography (OCT). METHODS: Forty participants (mean age 21 ± 2 years) had measures of ChT and ocular biometry taken during accommodation to 0, 3, and 6 diopter (D) stimuli, with the Spectralis OCT and Lenstar biometer. A Badal optometer and cold mirror system was mounted on both instruments, allowing measurement collection while subjects viewed an external fixation target at varying accommodative demands. RESULTS: The choroid exhibited significant thinning during accommodation to the 6 D stimulus in both subfoveal (mean change, -5 ± 7 μm) and parafoveal regions (P < 0.001). The magnitude of these changes varied by parafoveal meridian, with the largest changes seen in the temporal (-9 ± 12 μm) and inferotemporal (-8 ± 8 μm) meridians (P < 0.001). Axial length increased with accommodation (mean change, +5 ± 11 μm at 3 D, +14 ± 13 μm at 6 D), and these changes were weakly negatively associated with the choroidal changes (r2 = 0.114, P < 0.05). CONCLUSIONS: A small, but significant thinning of the choroid was observed at the 6 D accommodation demand, which was greatest in the temporal and inferotemporal parafoveal choroid, and increased with increasing eccentricity from the fovea. The regional variation in the parafoveal thinning corresponds to the distribution of the nonvascular smooth muscle within the uvea, which may implicate these cells as the potential mechanism by which the choroid thins during accommodation.
PURPOSE: To characterize the changes occurring in choroidal thickness (ChT) across the posterior pole during accommodation using enhanced-depth imaging optical coherence tomography (OCT). METHODS: Forty participants (mean age 21 ± 2 years) had measures of ChT and ocular biometry taken during accommodation to 0, 3, and 6 diopter (D) stimuli, with the Spectralis OCT and Lenstar biometer. A Badal optometer and cold mirror system was mounted on both instruments, allowing measurement collection while subjects viewed an external fixation target at varying accommodative demands. RESULTS: The choroid exhibited significant thinning during accommodation to the 6 D stimulus in both subfoveal (mean change, -5 ± 7 μm) and parafoveal regions (P < 0.001). The magnitude of these changes varied by parafoveal meridian, with the largest changes seen in the temporal (-9 ± 12 μm) and inferotemporal (-8 ± 8 μm) meridians (P < 0.001). Axial length increased with accommodation (mean change, +5 ± 11 μm at 3 D, +14 ± 13 μm at 6 D), and these changes were weakly negatively associated with the choroidal changes (r2 = 0.114, P < 0.05). CONCLUSIONS: A small, but significant thinning of the choroid was observed at the 6 D accommodation demand, which was greatest in the temporal and inferotemporal parafoveal choroid, and increased with increasing eccentricity from the fovea. The regional variation in the parafoveal thinning corresponds to the distribution of the nonvascular smooth muscle within the uvea, which may implicate these cells as the potential mechanism by which the choroid thins during accommodation.
Authors: Jie Lu; Hao Zhou; Yingying Shi; James Choe; Mengxi Shen; Liang Wang; Kelly Chen; Qinqin Zhang; William J Feuer; Giovanni Gregori; Philip J Rosenfeld; Ruikang K Wang Journal: Quant Imaging Med Surg Date: 2022-01
Authors: Danyang Wang; Rachel Ka Man Chun; Manli Liu; Roger Pak Kin Lee; Yuan Sun; Ting Zhang; Chuen Lam; Quan Liu; Chi Ho To Journal: PLoS One Date: 2016-08-18 Impact factor: 3.240