UCSF Neurological Surgery faculty since 2006
 
 
Kenneth Monson's research focuses on the role of the cerebral blood vessels in traumatic brain injury. Nearly all fatal head injuries involve damage to the cerebral vessels, but mechanisms and tolerance values for these injuries are not well understood. Similarly, little is known about the relationship between mechanical loading and the cerebrovascular biological response that invariably accompanies head trauma. In addition to their role as injured tissue, the cerebral vessels are an important structural element of the brain composite and thus influence the behavior of surrounding brain tissue to traumatic loads. Because of changes associated with development and aging, it is important that these questions be investigated across pediatric, young adult, and elderly age groups.
 
Building on work from our group characterizing the uniaxial mechanical properties of cerebral vessels and demonstrating the need to include them in head injury modeling, work in this area seeks to better define mechanical interactions between the vasculature and the surrounding brain tissues. Funded by the Centers for Disease Control and Prevention, this research is being accomplished through four objectives, the first two of which are the delineation of the multi-axial behavior of the cerebral vessels and the description of the relative response and susceptibility of branch regions. Healthy vessels obtained from temporal lobectomy surgeries are subjected to various combinations of axial stretch and pressure in vitro to define their characteristics. Properties of vessels with complex branched geometries are derived through inverse finite element reconstructions of experiments. A third area of focus is the characterization of the mechanical response of the pia-arachnoid complex. Pia-arachnoid material resected with blood vessels during temporal lobectomies are similarly tested in vitro to obtain their properties. The fourth objective in this area focuses on definition of the interactions between vessels and surrounding brain tissue and the importance of including branched vessels in models of this interaction. These issues are being addressed through physical and computational models.
 
In conjunction with efforts to describe the mechanical response of the cerebral vessels, Dr. Monson is also investigating traumatic mechanotransduction phenomena in these vessels in an effort to better understand the development of secondary injury. As funded by the National Institutes of Health, work is currently focused on relationships between mechanical loading and MMP activity. While this project is just getting underway, the temporal and spatial expression of MMPs in normal human and mouse cerebral vessels subjected to various levels of axial stretch ex vivo will be defined. Findings from the isolated vessel model will be compared against MMP measurements collected following controlled cortical impact in the normal mouse. Finally, wildtype and MMP-null mice will be subjected to CCI, and cerebrovascular permeability and MMP activity will be immuno-localized and compared with finite element model predictions of mechanical stretch in order to test the hypothesis that mechanical stretch induces breakdown of the blood-brain barrier through activation of MMPs.
 

Education, Training, and Previous Positions
 
1995: BS, Brigham Young University
1997: MS, Brigham Young University
2001: PhD, University of California, Berkeley
2001-2004: Visiting Postdoctoral Researcher, Department of Neurological Surgery, UCSF
2001-2005: Research Fellow, Department of Mechanical Engineering, UC Berkeley
2004-2006: Assistant Research Scientist, Department of Neurological Surgery, UCSF
 
Selected Honors and Awards
 
1989: Brigham Young University Trustees Scholar
1995: Magna Cum Laude, Brigham Young University
2006: National Institutes of Health Career Development Award
 
Contact
 
Kenneth Monson, PhD
University of California San Francisco
Brain and Spinal Injury Center
1001 Potrero Avenue, Bldg 1, Room 101
San Francisco, CA 94110
Phone: (415) 206-8094
E-mail: kenneth.monson@ucsf.edu
 
Selected Recent Publications
 
Goldsmith W, Monson KL. The state of head injury biomechanics: past, present, and future part 2: physical experimentation. Crit Rev Biomed Eng 2005;33(2):105-207.
 
Monson KL, Goldsmith W, Barbaro NM, Manley GT. Significance of source and size in the mechanical response of human cerebral blood vessels. J Biomech 2005;38(4):737-44.
 
Monson KL, Goldsmith W, Barbaro NM, Manley GT. Axial mechanical properties of fresh human cerebral blood vessels. J Biomech Eng 2003;125(2):288-94.
 
Zhang L, Bae J, Hardy WN, Monson KL, Manley GT, Goldsmith W, Yang KH, King AI. Computational study of the contribution of the vasculature on the dynamic response of the brain. Stapp Car Crash J 2002;46:145-64.
 
Monson KL, Goldsmith W, Barbaro NM, Manley G. Static and dynamic mechanical and failure properties of human cerebral vessels. In: Crashworthiness, Occupant Protection, and Biomechanisms in Transportation Systems. ASME. Mahmmod HF, Barbat SD, Baccouche MR (Eds.). 2000;49:255-65.