Dual-modality PET/CT scanning with negative oral contrast agent to avoid artifacts: introduction and evaluation

Area of Science:

• Radiology and Nuclear Medicine
• Gastrointestinal Imaging
• Medical Materials Science

Background:

• Dual-modality positron emission tomography (PET)/computed tomography (CT) is crucial for cancer staging and monitoring.
• Oral contrast agents are used to distend the bowel, improving image quality in PET/CT.
• Traditional contrast agents like barium can cause artifacts that interfere with PET data interpretation.

Purpose of the Study:

• To evaluate a novel oral contrast solution of locust bean gum (LBG) and mannitol (mannitol-LBG) for PET/CT scanning.
• To compare the efficacy of mannitol-LBG with barium and water in terms of bowel distention and PET artifact generation.
• To determine if mannitol-LBG can serve as a negative oral contrast agent in dual-modality imaging.

Main Methods:

• A prospective study involving 60 cancer patients undergoing PET/CT scans.
• Oral administration of either barium, water, or a 0.2% LBG and 2.5% mannitol solution (mannitol-LBG).
• Qualitative and quantitative assessments of intestinal distention and PET tracer uptake were performed.

Main Results:

• Mannitol-LBG demonstrated superior intestinal distention compared to both water and barium.
• Barium administration resulted in increased small bowel tracer uptake, suggesting potential PET artifacts.
• Mannitol-LBG and water showed comparable, lower tracer uptake, indicating minimal impact on PET data.

Conclusions:

• Mannitol-LBG is an effective negative oral contrast agent for PET/CT.
• It offers excellent bowel distention without inducing the PET artifacts associated with barium.
• This agent can enhance the diagnostic accuracy of PET/CT by providing clearer imaging.