Fig. 1. Schematic of diffusion correlation spectroscopy

Fig. 2. Comparison between tissue blood flow monitoring using fast DCS and traditional DCS^[27]. (a) Normalized intensity autocorrelation function; (b) blood flow index

Fig. 3. Schematic of noncontact DCT system with rotational scanning probe^[33]

Fig. 4. Calibration method of BFI in skeletal muscle^[23]. (a) Experimental protocol; (b) total hemoglobin concentration change; (c) BFI change

Fig. 5. Experimental protocol of the cerebral BFI calibration method^[37]

Fig. 6. Network architecture of the BFI quantification method based on LSTM^[46]

Fig. 7. Changes of cerebral blood flow (CBF) and cerebrovascular resistance (CVR) in 11 healthy subjects during cerebral autoregulation evaluation^[47]

Fig. 8. Changes of cerebral blood flow, mean arterial pressure, intracranial pressure, and cerebral oxygen tension during impaired cerebral autoregulation and intact cerebral autoregulation^[48]

Fig. 9. Cerebral blood flow images before and after mechanical thrombectomy and cerebral blood flow monitoring before, during, and after internal carotid artery recanalization^[49]

Fig. 10. Time series diagrams of cerebral blood flow under the change of intrathoracic pressure^[50]

Fig. 11. Blood flow changes of gastrocnemius muscle tissue obtained by DCS optical probe^[17]. (a)-(c) MRI images of gastrocnemius muscle; (d) diagram of DCS optical probe distance; (e) changes of blood flow in gastrocnemius muscle during cuff compression

Fig. 12. Typical muscle hemodynamic responses during bi-femoral artery bypass graft in a patient with peripheral arterial disease(PAD)^[51]. (a) rBF in left calf muscle; (b) rBF in right calf muscle

Fig. 13. Comparison results in a PAD patient before and after 3-month exercise training^[52]. (a) Changes of tissue blood flow three months ago; (b) changes of tissue blood flow under treadmill exercise load test after three months; (c) box diagram of tissue blood flow changes in exercise group and control group before and after three months

Fig. 14. Changes of gastrocnemius parameters in exercise group and control group of a PAD patient before and after three months^[53]. (a) Metabolic rate of oxygen (rMRO₂); (b) relative blood flow (rF); (c) tissue oxygen saturation (rStO₂)

Fig. 15. Changes of muscle BFI and StO₂ during the cycling exercise^[54]. (a) Schematic of riding; (b) muscle BFI and StO₂ for a representative subject during the cycling exercise

Fig. 16. Tissue blood flow monitoring of neck/head tumor^[55-56]. (a) Position diagram of hand-held detection probe; (b) average tumor rBF changes in patients with head and neck cancer after radiotherapy

Fig. 17. Box diagrams of breast tissue blood flow index changes during the neoadjuvant chemotherapy (NAC) treatment^[57]. (a) Healthy breast; (b) tumor breast

Table 1. Comparison of tissue blood flow monitoring methods^[65]