Purpose: Prompt and reliable detection of intracranial hemorrhage (ICH) has substantial clinical impact in diagnosis
and treatment of stroke and traumatic brain injury. This paper describes the design, development, and preliminary
performance characterization of a dedicated cone-beam CT (CBCT) head scanner prototype for imaging of acute
Methods: A task-based image quality model was used to analyze the detectability index as a function of system
configuration, and hardware design was guided by the results of this model-based optimization. A robust artifact
correction pipeline was developed using GPU-accelerated Monte Carlo (MC) scatter simulation, beam hardening
corrections, detector veiling glare, and lag deconvolution. An iterative penalized weighted least-squares (PWLS)
reconstruction framework with weights adjusted for artifact-corrected projections was developed. Various bowtie
filters were investigated for potential dose and image quality benefits, with a MC-based tool providing estimates of
spatial dose distribution.
Results: The initial prototype will feature a source-detector distance of 1000 mm and source-axis distance of 550
mm, a 43x43 cm2 flat panel detector, and a 15° rotating anode x-ray source with 15 kW power and 0.6 focal spot
size. Artifact correction reduced image nonuniformity by ~250 HU, and PWLS reconstruction with modified
weights improved the contrast to noise ratio by 20%. Inclusion of a bowtie filter can potentially reduce dose by 50%
and improve CNR by 25%.
Conclusions: A dedicated CBCT system capable of imaging millimeter-scale acute ICH was designed. Preliminary
findings support feasibility of point-of-care applications in TBI and stroke imaging, with clinical studies beginning
on a prototype.