PRM/NIR sensor for brain hematoma detection and oxygenation monitoring

Liu Zheng, H. Sang Lee, Sandor Lokos, Jin Kim, Daniel F. Hanley, David A. Wilson

Research output: Contribution to journalConference articlepeer-review


The pseudo-random modulation/near infrared sensor (PRM/NIR Sensor) is a low cost portable system designed for time-resolved tissue diagnosis, especially hematoma detection in the emergency care facility. The sensor consists of a personal computer and a hardware unit enclosed in a box of size 37 × 37 × 31 cm3 and of weight less than 10 kg. Two pseudo-random modulated diode lasers emitting at 670 nm and 810 nm are used in the sensor as light sources. The sensor can be operated either in a single wavelength mode or a true differential mode. Optical fiber bundles are used for convenient light delivery and color filters are used to reject room light. Based on a proprietary resolution-enhancement correlation technique, the system achieves a time resolution better than 40 ps with a PRM modulation speed of 200 MHz and a sampling rate of 1-10 Gs/s. Using the prototype sensor, phantom experiments have been conducted to study the feasibility of the sensor. Brain's optical properties are simulated with solutions of intralipid and ink. Hematomas are simulated with bags of paint and hemoglobin immersed in the solution of varies sizes, depths, and orientations. Effects of human skull and hair are studied experimentally. In animal experiment, the sensor was used to monitor the cerebral oxygenation change due to hypercapnia, hypoxia, and hyperventilation. Good correlations were found between NIR measurement parameters and physiological changes induced to the animals.

Original languageEnglish (US)
Pages (from-to)281-290
Number of pages10
JournalProceedings of SPIE - The International Society for Optical Engineering
StatePublished - Dec 1 1997
Externally publishedYes
EventProceedings of Biomedical Sensing, Imaging and Tracking Technologies II - San Jose, CA, United States
Duration: Feb 11 1997Feb 13 1997


  • Brain hematoma detection
  • Cerebral oxygenation monitoring
  • Low cost
  • Noninvasive
  • Portable
  • PRM/NIR Sensor

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'PRM/NIR sensor for brain hematoma detection and oxygenation monitoring'. Together they form a unique fingerprint.

Cite this