The assessment of choroidal thickness with spectral-domain optical coherence tomography during Valsalva maneuver

The purpose of the study was to evaluate the effect of Valsalva maneuver (VM) on choroidal thickness. All the volunteers underwent a detailed opthalmic examination. Third-generation Spectralis OCT device (software version 5.6.3.0; Spectralis OCT, Heidelberg Engineering, Dossenheim, Germany) was used for assessment. Subfoveal and perifoveal CT of all volunteers were measured by using EDI-OCT technology. Perifoveal CT was measured 1500 A mu m nasally and 1500 A mu m temporally apart from the foveal center. The measurements were repeated while volunteers were performing VM. Sixty-four eyes of 32 healthy volunteers were assessed. The volunteers were aged 29-50. The mean age was 32.8 +/- 6.6 years. Choroidal thickness measurements differed with statistical significance between resting position and VMin all regions (p < 0.001). While mean subfoveal CT was 350.64 +/- 87.73 A mu m during resting position, it was 369.95 +/- 90.12 A mu m during VM (p < 0.001). While mean nasal CT was 292.14 +/- 81.67 A mu m during resting position, it was 305.46 +/- 85.80 A mu m during VM (p < 0.001). While mean temporal CT was 325.93 +/- 80.91 A mu m during resting position, it was 343.21 +/- 81.53 A mu m during VM (p < 0.001). We found statistically significant increase in choroidal thickness during the VM in healthy volunteers. This result might be important for future studies researching autoregulation of choroidal and retinal blood flow in physiologic and pathologic conditions. Also, our study is noteworthy to stand out the errors in EDI-OCT measurements caused by unintentional breath holding of patients.