CMOS Image Sensor and System for Imaging Hemodynamic Changes in Response to Deep Brain Stimulation

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Deep brain stimulation (DBS) is a treatment for neurological and psychiatric disorders, but its mechanism of action remains unclear.
• DBS influences neural activity, altering cerebral blood flow and metabolic demands.
• The relationship between electrophysiological, hemodynamic, and behavioral changes in response to DBS is not well understood.

Purpose of the Study:

• To develop and present a miniaturized system for spectroscopic imaging of brain hemodynamics.
• To investigate the correlations between electrophysiological, hemodynamic, and behavioral changes during DBS.
• To explore the implications of these correlations for clinical benefits of DBS.

Main Methods:

• A miniaturized spectroscopic imaging system was designed, featuring a 144x144 pixel, high-sensitivity CMOS imager.
• The system includes illumination, focusing, analog-to-digital conversion, and μSD card storage for standalone operation.
• Utilized a capacitive transimpedance amplifier (CTIA) for high pixel sensitivity and characterized performance metrics like SNR and dynamic range.

Main Results:

• The developed system successfully detected temporal, spatial, and spectral hemodynamic changes in anesthetized rats during DBS.
• The CMOS imager demonstrated high sensitivity (minimum detectable intensity of 2.3 nW/cm²) and a dynamic range of 61 dB.
• The system enabled tetherless, standalone operation for in-vivo hemodynamic monitoring.

Conclusions:

• The miniaturized spectroscopic imaging system provides a novel tool for studying brain hemodynamics.
• This technology can help elucidate the mechanisms of action for deep brain stimulation.
• Further research can correlate observed hemodynamic changes with clinical outcomes in DBS therapy.