Clinical Molecular Imaging Research Group (CMIRG)

Andrew Quon, M.D.

3D CT has been available for over 10 years and can be readily performed at many modern imaging centers. The most common viewing formats: Virtual Colonoscopy and External 3D Volume "Fly-Around".

Some issues have diminished the utility of 3D CT:

• Small and flat lesions are difficult to see/characterize
• In CT colonography, stool cannot be differentiated from polyps without very strict bowel cleansing
• Steep learning curve for radiologists

FDG PET has superior accuracy to CT for many tumors and integrated PET/CT appears to add additional value. Although fused PET/CT images for 3D volume rendering is currently undefined and undescribed, it appears to provide additional beneficial data for image interpretation and may create new areas of clinical application. A particularly promising avenue is usage in pre-surgical/pre-procedural planning. Future work includes: (1) Further development of the 3D PET/CT software tools, (2) validation of this technique in more patients, and (3) use in tracers other than FDG.

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News & Updates

April 4, 2005

Proceeds from our project have been accepted for oral presenation at the Society of Nuclear Medicine Annual Meeting in Toronto this June 2005. Entitled: "NOVEL 3-D RENDERED FDG PET-CT VIRTUAL BRONCHOSCOPY AND COLONOGRAPHY FOR IMPROVED LESION LOCALIZATION AND PRE-SURGICAL EVALUATION."

June 20, 2005

We have been awarded Image of the Year at the 2005 Society of Nuclear Medicine (SNM) Annual Meeting in Toronto.

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Imaging Examples

Schematic of 3D Volume Rendered PET/CT Fusion Imaging
The standard CT and PET images (left) are rendered into three-dimensional volumes (middle) and then fused together into a 3D PET/CT fusion volume (right). Bone, soft tissue, and airway windows can be selected when 3D rendering the CT to emphasize a particular anatomical perspective.


PET/CT Virtual Colonography - View Movie [ | | ]
(A) Fusion PET/CT virtual colonoscopy in a patient with incomplete bowel preparation. A large amount of stool can be seen that would normally be difficult to differentiate from a polyp when using standard CT colonography. The FDG PET/CT fusion colonography movie facillitates the identification of an abnormal polyp because of focally increased FDG activity (orange color). (B) Retrospectively, the polyp was identified on the conventional 2D CT and PET/CT tomographs that was missed during the original interpretation.


3D Volume Rendered PET/CT "Fly-around" - View Movie [ | | ]
In a initial staging evaluation for lung cancer, a small abnormal focus is identified on the standard 2D CT and PET/CT tomographs near the left mainstem bronchus. The 3D external rotational PET/CT "fly-around" significantly helped direct the mediastinoscopy and bronchoscopy in localizing appropriate lymph nodes for biopsy. Further, two additional lymph nodes in the left hilum are seen that were seen on PET but could not be readily localized to any specific structure on the standard 2D CT tomographs.


CT Virtual Bronchoscopy - View Movie [ | | ]
3D CT virutal bronchoscopy in a patient with a large subcarinal lesion extending to the left paratracheal and peribronchial region as seen on the standard 2D CT and PET/CT tomographs. It is difficult to identify these lesions and their spatial relationship to the patient's airway using 3D CT "fly-through" imaging without FDG PET fusion.


PET/CT Fusion Virtual Bronchoscopy - View Movie [ | | ]
Same patient as in the above example, this time using fusion PET/CT 3D rendering. This "fly-through" uses a reconstruction technique that displays the CT anatomy as partially "transparent" (brown), therefore allowing visualization of the FDG PET activity (orange). The abnormal tumor abutting the left lower trachea, subcarina, and right bronchus are now clearly depicted.


Coronal PET/CT Cut Away - View Movie [ | | ]


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