Highly accurate thermal flow microsensor for continuous and quantitative measurement of cerebral blood flow

Chunyan Li, Pei ming Wu, Zhizhen Wu, Kanokwan Limnuson, Neal Mehan, Cameron Mozayan, Eugene V. Golanov, Chong H. Ahn, Jed A. Hartings, Raj K. Narayan

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Cerebral blood flow (CBF) plays a critical role in the exchange of nutrients and metabolites at the capillary level and is tightly regulated to meet the metabolic demands of the brain. After major brain injuries, CBF normally decreases and supporting the injured brain with adequate CBF is a mainstay of therapy after traumatic brain injury. Quantitative and localized measurement of CBF is therefore critically important for evaluation of treatment efficacy and also for understanding of cerebral pathophysiology. We present here an improved thermal flow microsensor and its operation which provides higher accuracy compared to existing devices. The flow microsensor consists of three components, two stacked-up thin film resistive elements serving as composite heater/temperature sensor and one remote resistive element for environmental temperature compensation. It operates in constant-temperature mode (~2 °C above the medium temperature) providing 20 ms temporal resolution. Compared to previous thermal flow microsensor based on self-heating and self-sensing design, the sensor presented provides at least two-fold improvement in accuracy in the range from 0 to 200 ml/100 g/min. This is mainly achieved by using the stacked-up structure, where the heating and sensing are separated to improve the temperature measurement accuracy by minimization of errors introduced by self-heating.

Original languageEnglish (US)
Article number87
JournalBiomedical Microdevices
Issue number5
StatePublished - Oct 11 2015


  • Cerebral blood flow
  • Self-heating error
  • Thermal flow microsensor
  • Thin-film resistive element

ASJC Scopus subject areas

  • Biomedical Engineering
  • Molecular Biology


Dive into the research topics of 'Highly accurate thermal flow microsensor for continuous and quantitative measurement of cerebral blood flow'. Together they form a unique fingerprint.

Cite this