Abstract
A whole‐body PET/CT scan extending from the vertex of the head to the toes of the patient is not feasible on a number of commercially available PET/CT scanners due to a limitation in the extent of bed travel on these systems. In such cases, the PET scan has to be divided into two parts: one covering the upper body segment, while the other covering the lower body segment. The aim of this paper is to describe and evaluate, using phantom and patient studies, a software tool that was developed to stitch two body segments and output a single whole‐body image set, thereby facilitating the interpretation of whole‐body PET scans. A mathematical model was first developed to stitch images from two body segments using three landmarks. The model calculates the relative positions of the landmarks on the two segments and then generates a rigid transformation that aligns these landmarks on the two segments. A software tool was written to implement this model while correcting for radioactive decay between the two body segments, and output a single DICOM whole‐body image set with all the necessary tags. One phantom, and six patient studies were conducted to evaluate the performance of the software. In these studies, six radio‐opaque markers (BBs) were used as landmarks (three on each leg). All studies were acquired in two body segments with BBs placed in the overlap region of the two segments. The PET/CT images of each segment were then stitched using the software tool to create a single DICOM whole‐body PET/CT image. Evaluation of the stitching tool was based on visual inspection, consistency of radiotracer uptake in the two segments, and ability to display the resultant DICOM image set on two independent workstations. The software tool successfully stitched the two segments of the phantom image, and generated a single whole‐body DICOM PET/ CT image set that had the correct alignment and activity concentration throughout the image. The stitched images were viewed by two independent workstations from two different manufacturers, attesting the ability of the software tool to produce a DICOM compliant image set. The study demonstrated that this software tool allows the stitching of two segments of a whole‐body PET/CT scan with minimal user interaction, thereby facilitating the interpretation of whole body PET/CT scans from a number of scanners with limited extent of bed travel.PACS number: 87.57.N, 87.57.uk
Highlights
In PET/CT imaging, some protocols require the acquisition of whole-body scans that cover the area from the top of the head to the bottom of the feet
The plot clearly shows that following decay correction, the activity concentration in the stitched slices is within 5% of the true value
This paper describes a software tool that was developed to stitch two PET/CT body segments into a single whole-body image set
Summary
In PET/CT imaging, some protocols require the acquisition of whole-body scans that cover the area from the top of the head to the bottom of the feet Such scans, are often acquired as two separate imaging sessions due to a limitation in the extent of bed travel on some commercially available PET/CT systems. The GE Discovery RX and STE scanners (GE Healthcare, Waukesha, WI) have a bed travel limited to 160 centimeters and cannot be used to image tall patients (> 160 cm) in a single imaging session In such cases, a whole-body PET/CT scan has to be divided into two acquisitions covering an upper and a lower body segment, respectively. This number is expected to increase in the future with the rising interest in PET/CT for bone imaging using NaF, since this type of scan requires an imaging extent that covers the top of the head to the bottom of the feet
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
