In neural tissues, the coupling between neural activity and blood flow is a physiological key principle in blood flow regulation. We used optical coherence tomography angiography to investigate stimulus-evoked hemodynamic responses in different microvascular layers of the human retina. Twenty-two healthy subjects were included. Vessel density before and during light stimulation was measured using optical coherence tomography angiography and assessed for the superficial, intermediate and deep capillary plexus of the retinal circulation. Volumetric blood flow was measured using a custom-built Doppler optical coherence tomography system. Our results show that flicker stimulation induced a significant increase in the vessel density of ...

The pathophysiology and timecourse of impairment in cutaneous microcirculatory function and structure remain poorly understood in diabetics, partly due to the lack of investigational tools capable of directly imaging and quantifying the microvasculature in vivo. We applied a new optical coherence tomography (OCT) technique, at rest and during reactive hyperemia (RH), to assess the skin microvasculature in diabetic people with foot ulcers (DFU, n=13), diabetics without ulcers (DNU, n=9) and matched healthy controls (CON, n=13). OCT images were obtained from the dorsal part of the foot, at rest and 30 seconds after deflation following 5 minutes of ...

Airway mucus obstruction is a hallmark of chronic lung diseases such as cystic fibrosis, asthma and COPD, and the development of more effective mucus mobilizing therapies remains an important unmet need for patients with these muco-obstructive lung diseases. However, methods for sensitive visualization and quantitative assessment of immediate effects of therapeutic interventions on mucus clearance in vivo are lacking. In this study, we determined if newly developed high-speed microscopic optical coherence tomography (mOCT) is sensitive to detect and compare in vivo effects of inhaled isotonic saline, hypertonic saline and bicarbonate on mucus mobilization and clearance in Scnn1b -transgenic mice with ...