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

Xiao Zhang, Muhammad S. Noor, Clinton B. McCracken, Zelma H.T. Kiss, Orly Yadid-Pecht, Kartikeya Murari

Research output: Contribution to journalArticlepeer-review

12 Scopus citations


Deep brain stimulation (DBS) is a therapeutic intervention used for a variety of neurological and psychiatric disorders, but its mechanism of action is not well understood. It is known that DBS modulates neural activity which changes metabolic demands and thus the cerebral circulation state. However, it is unclear whether there are correlations between electrophysiological, hemodynamic and behavioral changes and whether they have any implications for clinical benefits. In order to investigate these questions, we present a miniaturized system for spectroscopic imaging of brain hemodynamics. The system consists of a 144 × 144, 9.5-μ m pixel pitch, high-sensitivity, analog-output CMOS imager fabricated in a standard 0.35~ μ m CMOS process, along with a miniaturized imaging system comprising illumination, focusing, analog-to-digital conversion and μ SD card based data storage. This enables stand alone operation without a computer, nor electrical or fiberoptic tethers. To achieve high sensitivity, the pixel uses a capacitive transimpedance amplifier (CTIA). The nMOS transistors are in the pixel while pMOS transistors are column-parallel, resulting in a fill factor (FF) of 26%. Running at 60 fps and exposed to 470 nm light, the CMOS imager has a minimum detectable intensity of 2.3~ nW}/cm}2, a maximum signal-to-noise ratio (SNR) of 49 dB at 2.45 μ W}/cm}2 leading to a dynamic range (DR) of 61 dB while consuming 167~ μ A from a 3.3 V supply. In anesthetized rats, the system was able to detect temporal, spatial and spectral hemodynamic changes in response to DBS.

Original languageEnglish
Article number7247774
Pages (from-to)632-642
Number of pages11
JournalIEEE Transactions on Biomedical Circuits and Systems
Issue number3
StatePublished - 1 Jun 2016
Externally publishedYes


  • Biomedical optical imaging
  • CMOS image sensors
  • brain stimulation

ASJC Scopus subject areas

  • Biomedical Engineering
  • Electrical and Electronic Engineering


Dive into the research topics of 'CMOS Image Sensor and System for Imaging Hemodynamic Changes in Response to Deep Brain Stimulation'. Together they form a unique fingerprint.

Cite this