Multipurpose computed tomography window for fusion display with functional imaging

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Radiology

Background:

• Current positron emission tomography/computed tomography (PET/CT) and single photon emission CT (SPECT)/CT fusion displays have limitations, showing only one tissue type at a time, leading to suboptimal visualization.
• This hinders comprehensive interpretation of fused functional and anatomical imaging data.

Purpose of the Study:

• To develop and validate a multipurpose CT level/window designed to enhance the fusion display of PET/CT and SPECT/CT images.
• The aim is to improve the visualization of multiple tissue types simultaneously within a single fused image.

Main Methods:

• A multipurpose CT level/window was developed by modifying lookup tables to optimize contrast for soft tissue, lung, and bone.
• Thirty CT examinations from PET/CT scans were used, with development utilizing open-source software (MIPAV) and manual adjustments by a nuclear medicine physician.
• The developed window was validated by two nuclear medicine physicians who scored image quality.

Main Results:

• The multipurpose CT window successfully preserves soft tissue contrast and provides satisfactory lung parenchyma visualization.
• Bone tissue contrast is improved compared to standard displays, though still suboptimal versus conventional bone windows.
• Physicians rated the window as "very useful" (median score 3) for fusion with functional imaging.

Conclusions:

• The developed multipurpose CT window significantly enhances the fusion display of PET/CT and SPECT/CT images.
• It is valuable for case review and demonstrations on various devices, improving visualization without being intended for primary diagnostic interpretation.
• The tool offers a practical solution to current limitations in fused imaging display quality.