  An optical imaging system is proposed for quantitatively assessing jugular
venous response to altered central venous pressure. The proposed system
assesses sub-surface optical absorption changes from jugular venous waveforms
with a spatial calibration procedure to normalize incident tissue illumination.
Widefield frames of the right lateral neck were captured and calibrated using a
novel flexible surface calibration method. A hemodynamic optical model was
derived to quantify jugular venous optical attenuation (JVA) signals, and
generate a spatial jugular venous pulsatility map. JVA was assessed in three
cardiovascular protocols that altered central venous pressure: acute central
hypovolemia (lower body negative pressure), venous congestion (head-down tilt),
and impaired cardiac filling (Valsalva maneuver). JVA waveforms exhibited
biphasic wave properties consistent with jugular venous pulse dynamics when
time-aligned with an electrocardiogram. JVA correlated strongly (median,
interquartile range) with invasive central venous pressure during graded
central hypovolemia (r=0.85, [0.72, 0.95]), graded venous congestion (r=0.94,
[0.84, 0.99]), and impaired cardiac filling (r=0.94, [0.85, 0.99]). Reduced JVA
during graded acute hypovolemia was strongly correlated with reductions in
stroke volume (SV) (r=0.85, [0.76, 0.92]) from baseline (SV: 79$\pm$15 mL, JVA:
0.56$\pm$0.10 a.u.) to -40 mmHg suction (SV: 59$\pm$18 mL, JVA: 0.47$\pm$0.05
a.u.; p$<$0.01). The proposed non-contact optical imaging system demonstrated
jugular venous dynamics consistent with invasive central venous monitoring
during three protocols that altered central venous pressure. This system
provides non-invasive monitoring of pressure-induced jugular venous dynamics in
clinically relevant conditions where catheterization is traditionally required,
enabling monitoring in non-surgical environments.
