Multi-Exposure Speckle Imaging

Speckle contrast images acquired at different exposures

Multi-exposure speckle imaging (MESI) is an advanced form of laser speckle contrast imaging that offers more robust estimates of flow across a wider range of flow speeds. By revisiting the underlying physics behind LSCI to better account for the presence of static scatterers and capturing imagery at multiple exposure times, MESI enables the chronic tracking of cerebral blood flow. These improvements have allowed us to study the hemodynamics of ischemic stroke across timescales spanning seconds to months after the infarct.

**Chronic imaging of perfusion after ischemic stroke:** MESI used to track cerebral perfusion following an induced photothrombotic stroke. Green denotes areas with moderate flow deficit, while blue denotes areas with severe flow deficit ([Schrandt, 2015](/publication/schrandt-2015/)).
Chronic imaging of perfusion after ischemic stroke: MESI used to track cerebral perfusion following an induced photothrombotic stroke. Green denotes areas with moderate flow deficit, while blue denotes areas with severe flow deficit (Schrandt, 2015).
Imaging the effects of general anesthesia: Isoflurane anesthesia causes significant vasodilation and increases in cerebral blood flow as imaged with MESI (Sullender, 2022).