title: Iterative image reconstruction for cerebral perfusion CT using a pre-contrast scan induced edge-preserving prior.
abstract: Cerebral perfusion x-ray computed tomography (PCT) imaging, which detects and characterizes the ischemic penumbra, and assesses blood-brain barrier permeability with acute stroke or chronic cerebrovascular diseases, has been developed extensively over the past decades. However, due to its sequential scan protocol, the associated radiation dose has raised significant concerns to patients. Therefore, in this study we developed an iterative image reconstruction algorithm based on the maximum a posterior (MAP) principle to yield a clinically acceptable cerebral PCT image with lower milliampere-seconds (mA s). To preserve the edges of the reconstructed image, an edge-preserving prior was designed using a normal-dose pre-contrast unenhanced scan. For simplicity, the present algorithm was termed as 'MAP-ndiNLM'. Evaluations with the digital phantom and the simulated low-dose clinical brain PCT datasets clearly demonstrate that the MAP-ndiNLM method can achieve more significant gains than the existing FBP and MAP-Huber algorithms with better image noise reduction, low-contrast object detection and resolution preservation. More importantly, the MAP-ndiNLM method can yield more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps than the MAP-Huber method.
authors.affiliation: Department of Biomedical Engineering, Southern Medical University, Guangdong Guangzhou, People's Republic of China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Ma
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Gao
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.forename: Zhengrong
authors.initials: Z
authors.lastname: Liang
authors.forename: Qianjing
authors.initials: Q
authors.lastname: Feng
authors.forename: Wufan
authors.initials: W
authors.lastname: Chen
mesh_terms: D002560:Cerebrovascular Circulation; D003287:Contrast Media; D006439:Hemodynamics; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D012372:ROC Curve; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media