Multispectral Light Source for Retinal Surgery

Project Goals

Egg Membrane Illuminated by Light Source It has been shown that retinal surgical procedures often incur phototoxicity trauma of the retina as a result of illuminators used in surgery. In answer to this problem, we have developed a computer-controlled multispectral light source that drastically reduces retinal exposure to toxic white light during surgery.


Multispectral Light Source Fundamentally, our system achieves low phototoxic illumination by rapid illumination switching and by biasing illumination intensity towards low-phototoxic regions of the visible spectrum. To support these behaviors, we developed a light source employing red, green, yellow, and blue high-intensity LEDs for illumination. Combining independent control of each LED provides a highly tunable white light source with good color rendition. Other components of the illumination system include a microscope outfitted with stereo video cameras, a 3D display, a computer for video processing and light source control, and an optical channel for delivering illumination to the retina. The use of synchronized video capture to perform surgery is necessary to our approach. Video capture enables removal of illumination flicker and facilitates video processing algorithms that transform biased or incomplete color information in the raw video to a balanced and complete color video stream for display.


We have completed an In-Vitro study of cell cultures that compares the phototoxicity of a Xenon medical light source to the phototoxicity of our light source under various illumination configurations. The results of this study will be published soon. We are currently in-process of beginning an In-Vivo study with mice to determine the phototoxicity benefit of our light source.

Future Plans

Patents for our illumination system have been filed, and we are seeking an industry partner to commercialize our system for medical use. We are also working to improve the coupling of LED light into small fiber-optic light pipes as used in retinal surgery.

Project Personnel

JHU, Whiting School of Engineering


  • Dr. Russell H. Taylor
  • Dr. Greg Hager
  • Dr. Jin Kang

Staff Engineers

  • Balazs Vagvolgyi

Graduate Students

  • Raphael Sznitman
  • Seth Billings
  • Yi Yang
  • Diego Rother
  • Daniel Mirota

Undergraduate Students

  • Anshuman Gupta
  • Bao Luo Sun
JHU Hospital, Wilmer Eye Institute

Retinal Surgeons

  • Dr. Jim Handa
  • Dr. Peter Gehlbach

Retinal Surgery Residents

  • Ala Moshiri
  • Khoi-Nguyen Ha
JHU School of Medicine


  • Dr. Marisol Cano


  • Equinox Corporation
  • NIH grant EB007969
  • NIH grant EB006839
  • NSF Cooperative Agreement EEC9731478
  • Unrestricted grant from RBP (Wilmer)
  • Robert Bond Welch Professorship (JTH)
  • JHU Internal Funds

Affiliated labs


Raphael Sznitman, Seth Billings, Diego Rother, Daniel Mirotam, Yi Yang, James Handa, Peter Gehlbach, Jin U. Kang, Gregory D. Hager, Russell H. Taylor. Active Multispectral Illumination and Image Fusion for Retinal Microsurgery. IPCAI 2010, pp. 12-22.,

* Here put bibliographic references for this project; eventually will link to bibliographic data base * Also, you will (for now) need to populate the publications page on CIIS * In both cases, upload pdf files and make links to pdf papers

research.multispectral_light_source.txt · Last modified: 2019/08/07 16:01 by