Lightweight sCMOS-based high-density diffuse optical tomography

Research output: Contribution to journalArticlepeer-review

Authors

  • Karla M Bergonzi
  • Tracy M Burns-Yocum
  • Jonathan R Bumstead
  • Elise M Buckley
  • Patrick C Mannion
  • Christopher H Tracy
  • Eli Mennerick
  • Silvina L Ferradal
  • Adam T Eggebrecht
  • Joseph P Culver

External organisations

  • Washington University in St. Louis
  • Washington University School of Medicine
  • Fetal-Neonatal Neuroimaging and Developmental Science Center
  • School of Computer Science

Abstract

Though optical imaging of human brain function is gaining momentum, widespread adoption is restricted in part by a tradeoff among cap wearability, field of view, and resolution. To increase coverage while maintaining functional magnetic resonance imaging (fMRI)-comparable image quality, optical systems require more fibers. However, these modifications drastically reduce the wearability of the imaging cap. The primary obstacle to optimizing wearability is cap weight, which is largely determined by fiber diameter. Smaller fibers collect less light and lead to challenges in obtaining adequate signal-to-noise ratio. Here, we report on a design that leverages the exquisite sensitivity of scientific CMOS cameras to use fibers with ∼ 30 × smaller cross-sectional area than current high-density diffuse optical tomography (HD-DOT) systems. This superpixel sCMOS DOT (SP-DOT) system uses 200 - μ m -diameter fibers that facilitate a lightweight, wearable cap. We developed a superpixel algorithm with pixel binning and electronic noise subtraction to provide high dynamic range ( > 10 5 ), high frame rate ( > 6    Hz ), and a low effective detectivity threshold ( ∼ 200    fW / Hz 1 / 2 - mm 2 ), each comparable with previous HD-DOT systems. To assess system performance, we present retinotopic mapping of the visual cortex ( n = 5 subjects). SP-DOT offers a practical solution to providing a wearable, large field-of-view, and high-resolution optical neuroimaging system.

Details

Original languageEnglish
Pages (from-to)035006
JournalNeurophotonics
Volume5
Issue number3
Publication statusPublished - Jul 2018