Nuclear Medicine

Richard Laforest, PhD

Current Position:

Contact Information:
Washington University School of Medicine
Department of Radiology
Mallinckrodt Institute of Radiology (MIR)
MIR Tower 10th Floor
Tel: 314.362.8423
Fax: 314.362.9940

Ph.D., Experimental Nuclear Physics, Laval University, Quebec, Canada - 1994
M.S., Experimental Nuclear Physics, Laval University, Quebec, Canada - 1991
B.S., Physics, Laval University, Quebec, Canada - 1989

Richard Laforest is a researcher specializing in Clinical Nuclear Medicine, Positron Emission Tomography, and Multi-Modality Imaging, including PET/CT and PET/MR in both humans and small animals. Richard Laforest is the co-director of the small animal imaging facility of Washington University Medical School.

Research Interests:
PET is a noninvasive imaging technique that allows measurement of the concentration of radiotracers in the body of a living subject. Recent technological advances in detector design have allowed the construction of higher resolution tomographs for imaging radiopharmaceuticals in small laboratory animals, thus opening new areas of research of the brain, tumors, preclinical evaluation of new radiopharmaceuticals as well as gene expression and gene therapy.

The coregistration of functional images and anatomical images from MRI or CT allows for precise localization of activity distribution within the body of a living animal. Anatomical information, in conjunction to PET, can also be used for organ or tumor size determination. Knowing the exact size of an organ or tumor allows correction of the measured activity concentration for partial volume effects and will be used to improve the radiation dosimetry calculation. This will be especially crucial with nonstandard isotopes where partial volume effects are larger.

In addition to the common positron emitting isotopes used in nuclear medicine such as C-11, N-13, and O-15 and F-18, this laboratory is involved in the production of nonconventional radionuclides for PET imaging. Some of these isotopes are characterized by a longer half-life, allowing longitudinal studies on the same animal with a single injection of radiopharmaceuticals. Radiopharmaceutical kinetics can, thus, be studied on the same animal by successful PET imaging over several hours or days. Unfortunately, nonstandard isotopes decay with the emission of a high-energy positron and emit other concurrent gamma rays. Higher energy positron will travel longer distances from the point of emission in matter before annihilating. This will reduce the imaging performance by degrading the spatial resolution. Also, the emission of concurrent gamma rays will strongly affect the counting ability of the imaging device. Evaluation of these isotopes is thus mandatory before accurate quantitation can be achieved, both in small animal and human PET cameras. Improvement of imaging techniques is being investigated.
PET is an important noninvasive imaging technique and has become an accepted clinical tool in nuclear medicine. In particular PET imaging with [F-18]-Fluoro-2-deoxyglucose [FDG] for staging and localization of malignant cancerous tumors is now routinely performed. Nonetheless, significant advances in camera design and image reconstruction algorithms have been achieved recently, and efforts are being made to improve the overall utility of PET imaging and to develop new applications, notably in the areas of radiation treatment planning and cardiology.

Recent publications:
Cascade Removal and microPET Imaging with 76Br, R.Laforest, X.Liu, Phys. Med. Biol. 54 (2009) 1503-1531.

Quantitative Small Animal PET Imaging with non-Conventional Nuclides, X.Liu, R.Laforest. Nucl. Med. Biol. 36-5 (2009), 551-559.

Multimodal Imaging of Integrin Receptor-Positive Tumors by Bioliminescence, Fluorescence, Gamma Scintigraphy, and Single-Photon Emission Computed Tomograohy Using a Cyclic RGD Peptide Labeled with a Near-Infrared Fluorescent Dye and a Radionuclide, W. Barry Edwards, Walter J. Akers, Yunpeng Ye, Philip P. Cheney, Sharon Bloch, Baogang Xu, R. Laforest, Sam Achilefu, Mol. Imaging Vol.8-2 (2009) pp.101-110.\

Gold Nanocages as photothermal transducers for cancer treatment, Chen J., Glaus C. Laforest R., Zhang Q., Yang M., Gidding M., Welch MJ, Xia,Y, Small 2010-6(7) 811-7, PMID 20225187

Radiochemical Synthesis, Rodent Biodistribution and Tumor Uptake, and dosimetry Calculations of [(11)C] methylated LY2181308. Dence C., Laforest R., Sun X., Sharp TL, Welch MJ, Mach RH, Mol Imaging and Biol 2010-8 PMID 20376567

Exploring feature-based approaches in PET images for predicting cancer treatment outcomes, El Naqa I, Grisgby P., Apte A., Kidd E., Donnelly E., Khullar D., Chaudhari S., Yang D., Schmitt M., Laforest R., Thorstad W., Deasy JO. Pattern Recognit 2009, 42(6): 1162-1171 PMID 20161266

Generating Lung Tumor Internal Target Volumes from 4D-PET Maximum Intensity Projections, James M. Lamb, Clifford G. Robinson , Jeffrey D. Bradley , Richard Laforest , Farrokh Dehdashti , Benjamin M. White , Sara Wuenschel , Daniel A Low, Med. Phys. 38-10 (2011), 5732-5737. PMID 21992387

A scatter and randoms weighted (SRW) iterative reconstruction, J.C. Cheng, R. Laforest, J.A. O’Sollivan, Med. Phys. (2011) PMID 21815393

Quantitative Accuracy of MAP Reconstruction for Dynamic PET Imaging in Small Animals, J.C. Cheng, K. Shoghi, R.Laforest, Med. Phys. (2011) PMID22320813.

Feasibility and dosimetry studies for [18F]NOS as a potential PET radiopharmaceutical for inducible nitric oxide synthase (iNOS) in humans, Herrero P.1, Laforest R.1, Shoghi K.I.1, Zhou D.1, Ewald G.2, Pfeifer J.3, Duncavage E.4, Krupp K.1, Mach R.H.1 , Gropler R.J.1 , JNM 2012 PMID 22582045

NEMA NU4-2008 Comparison of Preclinical PET Imaging Systems A.L. Goertzen, Q. Bao, M. Bergeron, E. Blankemeyer, S. Blinder, M. Cañadas, A.F. Chatziioannou, K. Dinelle, E. Elhami, H.-S. Jans, E. Lage, R. Lecomte, V. Sossi, S. Surti, Y.-C. Tai11, J.J. Vaquero, E. Vicente, D.A. Williams and R. Laforest, JNM 2012 PMID22699999

Assessment of Progesterone Receptors in Breast Carcinoma by Positron Emission Tomography with 21-[18F]Fluoro-16α,17α-[(R)-1′-α-furylmethylidene)dioxy]-19-norpregn-4-ene-3,20-dione (FFNP), F. Dehdashti, R.Laforest, F.Gao, R.L.Aft, C.S.Dence, D.Zhou, K.I.Shoghi, B.A. Siegel, J.A. Katzenellenbogen, M. J. Welch, JNM 2012 PMID 22331216.

Book Chapters and Review Articles

Small Animal imaging: current technology and perspectives for oncological imaging, J. S. Lewis, S. Achilefu, J.R. Garbow, R. Laforest, M.J. Welch, , Eur. Jour. of Cancer 38 (2002) 2173-2188.
 Authors contributed equally to this review article.

“Micro”-Instruments for small Animal Imaging, Richard Laforest, Ph.D., Chapter 2 in Molecular Imaging of the Lungs published by Marcel Dekker Inc., Editors Daniel Schuster M.D., Timothy Blackwell M.D.,  Spring 2005.

“Animal PET” Yuan-Chuan Tai, PhD  and Richard Laforest, PhD, Annual Review of Biomedical Engineering ,7 ( 2005) 255-285.

Small Animal PET Imaging for the Study of Diseases and Drug Development, Richard Laforest, Medical Solutions, online edition, September 2005, p.19

Production of Non-Standard PET Radionuclides and the Application of Radiopharmaceuticals Labeled with these Nuclides, M.J. Welch, Richard Laforest, and Jason S. Lewis, Berlin, 2007, Ernst Scherring Res Found Workshop on Radio-nuclides Applications.