Exercise Induced Acute Changes In Systemic Blood Pressure Do Not Alter Choroidal Thickness

Abstract

Purpose: : This study was designed to measure choroidal thickness in patients manifesting an acute change in systemic arterial blood pressure using a portable spectral-domain optical coherence tomography device (iVue).

Methods: : Fifteen patients (15 eyes) undergoing cardiac exercise stress testing were scanned using a portable SD-OCT system (iVue). Two scan protocols were used: cross line scan for measuring choroidal thickness and the retina map scan to measure retinal thickness. Each patient was scanned before and within three minutes after the stress test. Blood pressure was measured at the same time as the acquisition of scans. Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroid/sclera junction at 500 um intervals up to 1000um temporal and nasal to the fovea. Retinal thickness was measured by the automated software. All choroidal thickness measurements were performed by 2 independent observers.

Results: : Fifteen patients (15 eyes) with a mean age of 60.6 (±10.4 years) were scanned. There was a significant increase in systolic but not diastolic pressure post stress testing (P<0.00000007). The mean choroidal thickness measurements showed no significant difference before and after the stress test (P>0.7). In addition, there was no significant difference in retinal thickness in the pre and post stress testing measurements (P>0.3).

Conclusions: : Choroidal thickness can be measured using a portable SD-OCT in the majority of eyes. There was no change in choroidal thickness or retinal thickness despite an acute change in the systemic systolic blood pressure induced by exercise.

Keywords: choroid • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)