Ph.D., 1976 - Rice University
Louisiana State University
Department of Physics & Astronomy
437 Nicholson Hall, Tower Dr.
Baton Rouge, LA 70803-4001
My primary area of research has been electron beam radiotherapy (Hogstrom and Almond 2006 and Hogstrom 2003), where my research groups have contributed to improve multiple electron beam treatment techniques (e.g. total skin irradiation, total scalp irradiation, intraoperative radiotherapy, and electron arc therapy). Treatment devices (scattering foils, collimators, eyeshields, and boluses) and multiple algorithms for dose calculations and treatment planning were researched and developed at The University of Texas M D Anderson Cancer Center (1979 to 2004) and Louisiana State University and the Mary Bird Perkins Cancer Center (MBPCC) (2004 to present).
Most recently, we are developing methods that elevate electron beam therapy to an equal technological level as intensity modulated x-ray therapy (IMXT), proton therapy (IMPT), and high-dose rate (HDR) brachytherapy. In 2009, we translated bolus electron conformal therapy (ECT) with .decimal LLC, making it commercially available in the United States for the first time, and we verified its accuracy when using the pencil beam algorithm (PBA), pencil beam redefinition algorithm (PBRA), and fast Monte Carlo algorithm for dose calculation (Carver et al 2013, 2016). With adjunct assistant professor Robert Carver, MBPCC continues to develop with .decimal LLC, tools necessary for electron intensity modulation (IM), which include methods for planning and delivery of IM bolus ECT. Kudchadker et al (2002) showed that IM can significantly improve bolus ECT PTV dose homogeneity. In collaboration with assistant professor Rui Zhang, treatment plans for postmastectomy radiotherapy are being studied; we believe IM bolus ECT can provide dose plans superior to those possible with helical tomotherapy or volumetric arc therapy (VMAT), our current standard of practice, which previously had been shown superior to conventional electron therapy (Ashenafi et al 2010).
Over many years we developed multiple collimating devices, e.g. electron multi-leaf collimator (eMLC), intraoperative electron therapy cones, variable applicators, and tungsten eyeshields. With the MBPCC clinic utilizing a fleet of Elekta radiotherapy machines, recent research has shown how to reduce to approximately one-half the cumbersome weight of present Elekta electron applicators (Pitcher 2015, Pitcher et al 2016). Because of their interdependence, the dual scattering foil system is often designed at the same time as electron applicators; hence, we have developed tools and solutions for optimizing Elekta dual scattering foil system design (Carver et al 2014). Also, because Elekta standing wave linear accelerators utilize recirculated RF power, we developed a light, inexpensive permanent magnet spectrometer to measure the electron energy spectrum (McLaughlin et al 2015) and to assist in required, frequent beam tuning. Currently, associate professor Kip Matthews is supervising efforts to develop a real-time version of the spectrometer.
We have recently studied Auger electron therapy, which has the potential to target cancer with high-LET radiation at the cellular level, providing a sufficient concentration of iododeoxyuridine (IUdR) can preferentially target the cancer cells. Auger electron therapy uses monochromatic x-rays from the LSU CAMD synchrotron light source to create Auger electrons by interacting with the iodine in the IUDR, which has been incorporated into cellular DNA. We studied (1) dosimetry methods using ion chambers (Oves et al 2008 and Brown et al 2012a)and radiochromic film (Brown et al 2012b) and (2) cell survival as a function of IUdR concentration in CHO cells (Dugas et al 2011) and monochromatic x-ray energy from 25-35 keV in 9L glioma cells (Alvarez et al 2014). Present work with associate professor Kip Matthews is aimed at improving our original biomedical beam line (Dugas et al 2008) with one that uses a double bent Laue monochromator and a multipole wiggler to achieve higher x-ray energies for ongoing x-ray imaging and future therapy research.