Evaluation of cerebral circulation during retrograde perfusion by laser speckle flowgraphy

Laser speckle flowgraphy (LSFG) is an ophthalmologic equipment that qualitatively detects the blood flow of the optic nerve head, which is known to be related with cerebral microcirculation. LSFG can also measure the mean blur rate, which quantitatively calculates the blood flow. We aimed to assess the utility of LSFG in the evaluation of cerebral perfusion during aortic surgery under hypothermic circulatory arrest with retrograde and antegrade cerebral perfusion. Two patients underwent total arch replacement for aneurysm. The blood flow of the optic nerve head was monitored with LSFG and the mean blur rate value was measured during the surgery. The LSFG could detect the blood flow quantitatively in the optic nerve head during both retrograde and antegrade cerebral perfusion; and the value was correlated with rSO2 value.