Pulse transit time (PTT) is an important physiological parameter that directly correlates with the elasticity and compliance of vascular walls and variations in blood pressure. This paper presents a PTT estimation method based on photoplethysmographic imaging (PPGi). The method utilizes two opposing cameras for simultaneous acquisition of PPGi waveform signals from the index fingertip and the f...

Among the respiratory events that may occur during nocturnal noninvasive ventilation (NIV), differentiating between central and obstructive events requires appropriate indicators of respiratory effort. The aim of the present study was to assess pulse transit time (PTT) as an indicator of respiratory effort under NIV in comparison with oesophageal pressure (P(oes)). During wakefulness, PTT was c...

OBJECTIVE Adult acquired flatfoot deformity is generally associated with a collapsing medial longitudinal arch and a progressive loss of strength of the posterior tibial tendon (PTT). This condition is commonly associated with PTT dysfunction or rupture, which can have an arthritic or a traumatic etiology. Several causes have been proposed to explain the clinical evidence of tendon degeneration...

Aortic pulse wave velocity (PWV), calculated from pulse transit time (PTT) using 2 separate pulse recordings over a known distance, is a significant biomarker of cardiovascular risk. This study evaluates a novel method of determining PTT from waveform decomposition of central aortic pressure using a single pulse measurement. Aortic pressure was estimated from a transformed radial pulse and deco...

Pulse transit time (PTT) is being widely pursued for cuff-less blood pressure (BP) monitoring. Most efforts have employed the time delay between ECG and finger photoplethysmography (PPG) waveforms as a convenient surrogate of PTT. However, these conventional pulse arrival time (PAT) measurements include the pre-ejection period (PEP) and the time delay through small, muscular arteries and may th...

Phototherapies such as photodynamic therapy (PDT) and photothermal therapy (PTT), due to their specific spatiotemporal selectivity and minimal invasiveness, have been widely investigated as alternative treatments of malignant diseases. Graphene and its derivatives not only have been used as carriers to deliver photosensitizers for PDT, but also as photothermal conversion agents (PTCAs) for PTT....