The J. Webster Stayman Lab studies both emission tomography and transmission tomography (CT, tomosynthesis and cone-beam CT). Our research activities relate to 3-D reconstruction, including model-based statistical / iterative reconstruction, regularization methods and modeling of imaging systems. We are developing a generalized framework for penalized likelihood (PL) reconstruction combining statistical models of noise and image formation with incorporation of prior information, including patient-specific prior images, atlases and models of components / devices known to be in the field of view. Our research includes algorithm development and physical experimentation for imaging system design and optimization.