Abstract
Purpose:
To analyze the choroidal thickness in relation with the variability of ambulatory blood pressure(BP) in normal subjects and open angle glaucoma(OAG) patients.
Methods:
12 normal subjects and 36 OAG patients were enrolled in this study. The thickness of ganglion cell complex(GCC), retinal nerve fiber layer(RNFL) and choroid were measured at three macular area & five peripapillary area with Fourier-domain optical coherence tomography(FD-OCT, RTVue-100). Blood pressure(BP), heart rate and mean arterial pressure were measured in all subjects using a 24 hours ambulatory BP monitoring device. The variability parameters were demonstrated as weighted fashion standard deviation(wSD) of ambulatory BP. Visual field(VF) parameters, axial length(AL) and spherical equivalent(SE) were measured in all subjects. Mann-Whitney analysis was conducted to compare the choroidal thickness and the GCC & RNFL thickness between normal subjects and OAG patients. Spearman’s correlation analysis was performed to correlate the choroidal thickness with mean deviation(MD) of VF, AL, SE, and the GCC & RNFL thickness.
Results:
The mean GCC, RNFL and macular & peripapillary choroidal thickness measurements were 95.87±4.78μm, 107.21±10.49μm and 283.63±57.90μm & 209.88±49.57μm in normal subjects, 82.93±13.06μm, 89.32±17.12μm and 177.98±48.81μm & 117.46±45.90μm in OAG patients, respectively. The GCC, RNFL and choroidal thickness was thinner in OAG patients than normal subjects at all areas significantly(p<0.001). MD, SE, AL, GCC, RNFL and wSD were associated with the choroidal thickness significantly in OAG patients(MD; p=0.045, r=0.266, SE; p=0.022, r=0.310, A/L; p=0.028, r=-0.252, GCC; p=0.028, r=0.457, RNFL; p=0.009, r=0.347, wSD; p=0.032, r=-0.298). However, there was no correlation between the choroid thickness and all measurements in normal subjects. In OAG patients with nocturnal dip over 10%, the choriodal thickness was positively correlated with the RNFL thickness(p=0.027, r=0.404).
Conclusions:
The choroid thickness at macular & peripapillary areas in OAG patients is significantly thinner in normal subjects. The choroidal thickness in OAG patients is correlated the variability of ambulatory BP significantly. Thus, the choroidal thinning & the variability of ambulatory BP is somehow related with OAG and may be a useful diagnostic parameter for OAG.
Keywords: 452 choroid •
436 blood supply •
531 ganglion cells