Evaluation of seizure-induced neural injury using optical coherence microscopy

Epilepsy affects 2.2 million Americans and 65 million people worldwide.  Seizures have the potential to kill neurons and cause brain injury, leading to reorganization of neural circuits, and progressively more severe epilepsy. Our goal is to quantify neural injury caused by seizures, to provide information to physicians that will assist in selecting optimal treatments for epileptic patients. This quantification is difficult to carry out with current histopathology methods due to inability to compare pre- and post-seizure neural tissue. We plan to overcome these limitations by carrying out Optical Coherence Microscopy (OCM) imaging of an in vitro organotypic hippocampal culture model of epilepsy before, during, and after seizures. 

 

OCM is an emerging optical imaging technique that enables micron-scale, cross-sectional, and three-dimensional (3D) imaging of biological tissues in situ and in real-time. OCM functions as a type of “optical biopsy,” imaging tissue microstructure with resolutions approaching that of standard histopathology, but without the need to remove and process tissue specimens.  

 

In the summer of 2013, we designed and constructed a new spectral domain OCM capable of achieving ~2.8 um axial and ~3.2 um transverse resolution in brain tissue, and demonstrated the feasibility of using OCM to non-invasively quantify neuron numbers in organotypic hippocampal cultures.  This summer, we will design a recording chamber and integrate it with the OCM imaging system to enable simultaneous imaging and electrical recording of organotypic hippocampal cultures. We will also determine the relationship between seizure load and neural death in organotypic hippocampal cultures.

 

Results of this project will lead to a better understanding of the relationship between seizures and death of neurons, potentially leading to improved treatments for patients with epilepsy.