Robust and efficient methods for proton computed tomography.

Proton computed tomography (pCT) is a recent promising imaging modality with the goal of generating accurate 3D maps of relative stopping power (RSP) with respect to water. Since the early developments of this imaging technique in 1970's, there have been significant improvements regarding the reconstruction of accurate RSP which makes pCT a reliable alternative to X-ray CT for planning proton therapy treatments. There are several conditions in pCT that can negatively affect the accuracy of pCT images. The goal of this dissertation is developing efficient image reconstruction methods generating accurate RSP values under both normal and critical conditions.