Greater cancer detection is possible with 4-D PET image reconstruction

June 6, 2011

A study introduced at SNM's 58th Annual Meeting is advancing a positron emission tomography (PET) imaging method that uses new 4D image reconstruction to achieve the highest diagnostic capability for the detection of cancer. Mounting evidence shows that PET imaging, which provides visual representations of bodily functions, is significantly more sensitive when used with cutting-edge 4D image reconstruction technology that accounts for patient respiration and produces clearer, more easily interpreted images.

" with 4D image reconstruction could potentially help with early , which is an imperative in the field of nuclear oncology," says Si Chen, lead author of the study, Johns Hopkins School of Medicine, Baltimore, Md. "The results of this study and our other studies indicate that the sensitivity of small cancer lesion detection for patients will likely benefit from this novel image reconstruction method, which incorporates an accurate and patient-specific respiratory motion estimation algorithm we previously developed. The improved would allow physicians a more informed understanding of a patient's situation in order to provide better treatment planning for the best possible outcome."

The objective of the study was to quantify the improvement of PET image quality using the 4D PET image reconstruction method with respiratory motion compensation compared to a more conventional 3D PET image reconstruction method. The researchers evaluated the image reconstruction methods using the receiver operating characteristic (ROC) methodology, which is based on signal detection theory widely adopted in diagnostic radiology. A ROC curve is a graphical plot of the sensitivity versus specificity for lesion detection based on the reconstructed PET images. Realistically simulated PET images were employed in this evaluation study using the 4D XCAT phantom—a digital anthropomorphic phantom that realistically models a typical patient's anatomy, respiratory and cardiac motions. A total of twelve spherical tumors of 10mm diameter were planted inside the lungs and liver of the phantom, which was input to realistic simulation of PET data acquisition using another methodology called Monte-Carlo simulation. The simulated PET data were then reconstructed using both imaging reconstruction methods. The researchers used a mathematical observer, i.e., channelized hotelling observer (CHO), to mimic the interpretation of these PET images by human observers.

Using these methodologies, researchers were able to compare the sensitivity and specificity of the two image reconstruction methods and found that the 4D PET image reconstruction method with respiratory compensation improved the detection sensitivity for the cancer lesions in the liver and lungs. This indicates that evaluation of cancer for lesions smaller than 10 millimeters could be enhanced by compensating for respiratory motion with the 4D image reconstruction method.

Explore further: Coming soon: 3-D imaging that flies 'through' and 'around' cancer

More information: Scientific Paper 150: S. Chen, B.M.W. Tsui, Johns Hopkins School of Medicine, Baltimore, MD; "Evaluation of a new 4D PET image reconstruction method with respiratory motion compensation in a CHO study," SNM's 58th Annual Meeting, June 4-8, 2011, San Antonio, TX.

Related Stories

Hybrid scanner brings molecular functioning to the forefront

June 15, 2009

A major barrier to developing a hybrid positron emission tomography (PET)/magnetic resonance (MR) imaging system could be removed by using a novel approach for reconstructing data, according to researchers at SNM's 56th Annual ...

Less is more in cancer imaging

February 11, 2010

When one diagnoses a cancer patient, it's important to gather as much information about that person as possible. But who would have thought an accurate diagnosis would depend on throwing some of that information away?

Recommended for you

Oxygen can impair cancer immunotherapy in mice

August 25, 2016

Researchers have identified a mechanism in mice by which anticancer immune responses are inhibited within the lungs, a common site of metastasis for many cancers. This mechanism involves oxygen inhibition of the anticancer ...

Stem cell propagation fuels cancer risk in different organs

August 25, 2016

The idea that stem cells - special cells that divide to repair and generate tissues - might be the major determinant of cancer risk has provoked great debate in the scientific community. Some researchers maintain that environmental ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.