Benefits Study of Respiratory-gated PET Acquisition in Lung Disease

Benefits Study of a Respiratory Gating Protocol for Positron Emission Tomography: Application on the Lungs

Fluorodeoxyglucose (FDG) positron emission tomography (PET) is now widely used for cancer imaging purpose, notably for preoperative work-up. It aims at visualizing organs metabolism. In case of cancer, metabolism is, classically, increased and some hot spots are visible on PET images. Because of respiratory motion some lung tumours (especially the smallest ones) can be falsely interpreted by the clinician.

The investigators developed a respiratory-gated PET method in order to reduce the motion issue. The investigators designed a study to investigate its effect on lung cancer (primary or metastasis) to check if it improves the sensitivity/specificity of PET imaging of the lungs.

To that aim, patients presenting a lung nodule on a CT examination can be proposed to participate this study. After the standard PET acquisition (acquired in free-breathing), an additional 10 minutes respiratory-gated PET acquisition is performed without additional injection. After that, a breath-hold (~10s) CT is performed.

Inclusion Criteria:

• patient has one or more lung lesion(s) less than 35 mm visible on a CT image
• age : over 18 years
• patients gave their written informed consent

Exclusion Criteria:

• pregnancy
• patient has at least one lesion more than 35 mm in its great axis