Windows to the Brain: Novel concept for providing non-invasive, chronic access to neural tissues for laser-based diagnostics & therapeutics

Friday, February 21, 2014 - 11:00 p.m. to Saturday, February 22, 2014 - 10:55 p.m.
McDonnell Douglas Engineering Auditorium

ChEMS Seminar

Guillermo Aguilar

Professor and Chair

Department of Mechanical Engineering

University of California, Riverside

 

One of the recent research thrusts in my research group aims at developing a novel transparent polycrystalline Yttria-Stablized-Zirconia (YSZ) cranial implant (“window”) that enables life-long, non-invasive delivery and/or collection of laser light into and from shallow and deep brain tissue on demand. 

 

Such an implant would allow for real-time and highly precise visualization and treatment of diverse brain pathologies, such as those resulting from traumatic brain injury (TBI) or brain tumors, without the need of highly-invasive craniotomies or trepanation procedures. In an ideal scenario, an YSZ implant would allow for the delivery and/or collection of laser light to/from multiple affected areas within the brain, which must be detected and treated chronically. The window could be permanently covered with native scalp that can be rendered temporarily transparent on demand in a minimally-invasive manner using percutaneous drug delivery of optical clearing agents (OCAs) with microneedles.

 

In collaboration with other research groups at UCR, an YSZ implant has been successfully fabricated with current-activated powder-assisted densification (CAPAD) processing method. Waveguides have been written across millimeter-thick YSZ using femtosecond laser irradiation with ultralow energies. Optical coherence tomography images of YSZ implanted on a mouse model have suggested that the transparent YSZ implant improves axial and lateral resolution and penetration depth into the brain. Porcine skin samples treated with OCA using microneedles have already demonstrated significant optical clearing. All these results suggest that novel YSZ implants in conjunction with OCA can be used in delivering and/or collecting laser light to the brain for treatment and monitoring of TBI and other brain pathologies. A summary of these results as well as ongoing and future studies pertaining to this research thrust will be presented.

 

Biosketch      

Prof. Guillermo Aguilar received his B.S. in Mechanical and Electrical Engineering from the National Autonomous University of Mexico (UNAM) in 1993.  He earned his M.S. and Ph.D. also in Mechanical Engineering at the University of California Santa Barbara (UCSB) in 1995 and 1999, respectively.



Since 2003 Prof. Aguilar joined the Department of Mechanical Engineering at University of California Riverside (UCR), where he was promoted to Associate Professor in 2007, Full Professor in 2012 and currently serves as the Department Chair.  His current research interests include cryogen spray cooling, laser-tissue interactions, biomedical optics and medical lasers.