Robust, transportable retinal arterial velocity waveform-shape metrics from beat-resolved laser Doppler holography for functional microvascular bed characterization

Beat-resolved retinal arterial velocity waveforms measured by laser Doppler holography (LDH) encode pulsatility, vascular loading, and the cumulative functional state of the downstream microvascular bed. For clinical translation, these waveforms must be summarized by descriptors that remain interpretable and transportable when absolute velocity calibration is uncertain. We present a clinician-oriented library of beat-wise arterial waveform-shape metrics computed from a nonnegative velocity waveform $v(t)\ge 0$ over one cardiac period $T$. The endpoint set spans timing, cumulative-distance geometry, pulsatility, crest morphology, temporal concentration, slope kinetics, late-cycle persistence, and compact spectral or representation-fidelity descriptors. All definitions are explicit, auditable, and computable from either raw or band-limited waveforms, enabling automated beat-by-beat reporting from short acquisitions. By construction, the library emphasizes gain-invariant or gain-robust descriptors suited to longitudinal, multisite, and calibration-light studies of retinal microvascular function.