Photoacoustic and optical coherence tomography of epilepsy with high temporal and spatial resolution and dual optical contrasts.

Epilepsy mapping with high spatial and temporal resolution has great significance for both fundamental research on epileptic neurons and the clinical management of epilepsy. In this communication, we demonstrate for the first time in vivo epilepsy mapping with high spatial and temporal resolution and dual optical contrasts in an animal model. Through the variations of a depthresolved optical coherence tomography signal with optical scattering contrast, we observed that epileptic neuron activities modulated the optical refractive index of epileptic neurons and their surrounding tissue. Simultaneously, through neurovasculature coupling mechanisms and optical absorption contrast, we used photoacoustic signals to document the hemodynamic changes of the microvasculature surrounding the epileptic neurons. The epilepsy mapping results were confirmed by a simultaneously recorded electroencephalogram signal during epileptic seizure. Our new epilepsy mapping tool, with high temporal and spatial resolution and dual optical contrasts, may find many applications, such as drug development and epilepsy surgery.