Choroidal thickness change during standardized Valsalva maneuver.

<p>Enhanced depth imaging (EDI) scan aligned to axis connecting fovea and center of optic disc in 22-year-old male. Note that adaptive compensation was performed to enhance choroid visibility. Choroidal thickness was defined as the vertical distance between the outer border of the retinal pigment epithelium and the inner surface of the sclera. The peripapillary chorodidal thickness was measured at the point 250 μm temporally from the termination of the Bruch’s membrane openings (BMO). The subfoveal choroidal thickness (A) was 336 μm at baseline and 324 μm during the standardized Valsalva maneuver. The peripapillary choroidal thickness (B) was 154 μm at baseline and 146 μm during the standardized Valsalva maneuver.</p

Anterior lamina cribrosa depth, neural canal opening diameter, and choroidal thickness change during standardized Valsalva maneuver.

<p>Anterior lamina cribrosa depth, neural canal opening diameter, and choroidal thickness change during standardized Valsalva maneuver.</p

Demographics of the subjects.

<p>Demographics of the subjects.</p

Optic nerve head parameters change during standardized Valsalva maneuver.

<p>Optic nerve head parameters change during standardized Valsalva maneuver.</p

Distribution of anterior lamina cribrosa depth change during standardized Valsalva maneuver.

<p>The histogram presents the distribution of the anterior LC depth change during the standardized Valsalva maneuver. Twenty-nine eyes (60.4%) showed significant anterior displacement of the LC during the standardized Valsalva maneuver. Only three eyes (6.3%) showed posterior displacement (10.0–17.0 μm). The vertical red dotted line depicts the 1.96-times intersession SD of the OCT measurements (22.5 μm).</p

Anterior displacement of lamina cribrosa (LC) during standardized Valsalva maneuver.

<p>Enhanced depth imaging (EDI) optic disc scan of 26-year-old healthy male (A) at baseline and (B) during standardized Valsalva maneuver. Note that adaptive compensation was performed to enhance lamina cribrosa (LC) visibility. The anterior LC depth (LCD) was defined as the maximal distance between the reference plane connecting the Bruch’s membrane openings (BMO) and the anterior LC surface. The LCD decreased from 607 μm at baseline to 563 μm during the Valsalva maneuver, while the intraocular pressure (IOP) increased from 14 mmHg at baseline to 17 mmHg.</p

Patient demographics.

<p>Patient demographics.</p

Factors associated with increased vertical-horizontal ALID difference.

<p>Factors associated with increased vertical-horizontal ALID difference.</p

Comparison of LC structure in HTG, NTG and Healthy eyes.

<p>Comparison of LC structure in HTG, NTG and Healthy eyes.</p

Schematic diagram showing LC-structural differences among HTG, NTG and healthy eyes.

<p>In healthy eyes, the anterior laminar insertion locates more posteriorly in superior and inferior axis compared to nasal and temporal axis, which results in vertical-horizontal ALID difference (small red arrow in the first line). In NTG eye, the vertical (superior-inferior) LC insertion locates much deeper than horizontal (nasal-temporal) LC insertion, which lead to increased vertical-horizontal ALID difference (large, thicker red arrow in the second line). The laminar curvature is increased in both meridians (yellow shaded area). In HTG eye, the horizontal anterior laminar insertion further locates posteriorly, which results in decreased vertical-horizontal ALID difference. The laminar curvature is much increased, so that the ‘w-shape’ contour changes to ‘u-shape’ contour in vertical meridian. The green points indicate Bruch’s membrane opening, and the thin green dotted-line corresponds to the reference plane connecting the BMO. The thicker green (healthy), yellow (NTG), and orange (HTG) dotted-lines indicate the anterior LC.</p