Guidance for CT Departments Desiring to Optimize Protocols for Multiple Scanner Architectures
T Szczykutowicz1*, F Ranallo2, (1) University Wisconsin-Madison, Madison, WI, (2) University of Wisconsin, Madison, WISU-C-134-6 Sunday 1:00PM - 1:55PM Room: 134
Purpose: Clinical protocol development must consider a CT scanners architecture both in hardware and software. Differences in tube output, beam collimation, availability of iterative reconstruction, etc., may only allow some protocols to be properly performed on higher end scanners due to clinical constraints like breath hold duration and contrast dynamics. This study presents an overview of techniques for translating and optimizing a protocol from one scanner to another. Cases in which protocols are not compatible with a given scanner architecture are also discussed.
Methods: At our institution, intensive protocol optimization is performed for each protocol using a single scanner architecture. Once a protocol is optimized in both technical and clinical parameters, the protocol can be translated to other scanner architectures (both older and newer). Essential restraints on the translation process include the maximum clinically allowable scan time and the maximum tube output of the scanner. Successful translation can be done if scan parameters can be modified within these essential constraints. If this is not possible then compromises have to be made that can affect clinical performance. Mathematical relationships related to tube output and clinical considerations will be discussed that guide the transformation and any needed compromises.
Results: Several test cases are presented providing details of translating optimized protocols to an older and newer CT scanner architecture. Cases in which older scanners cannot provide the required performance are common for angiography exams that require high spatial resolution, thin reconstructed slice thickness, low noise, and fast scan times due to breath hold and contrast dynamic constraints.
Conclusion: Understanding the limitations of older generation CT scanners and the benefits of newer CT architectures is critical for maintaining a uniquely optimized set of CT protocols across a wide range of CT architectures.
Funding Support, Disclosures, and Conflict of Interest: Equipment grant from GE healthcare.