As the first provider of PET/CT in the region, East Jefferson General Hospital demonstrated its commitment to offering the most up-to-date cancer imaging technology. The recent acquisition of the GE Discovery 690 PET/CT with Time of Flight reiterates the hospital's commitment to remaining on the forefront of molecular imaging.
The new scanner features many advances compared to older generation scanners. "PET/CT couples a PET scanner and a CT scanner in the same gantry; both the PET and CT components of the Discovery 690 produce higher resolution images with lower radiation dose compared to older models," explains radiologist Dr. Puneet Singha. The PET portion of the scanner incorporates 24 rings of lutetium-based crystals (instead of the traditional BGO crystals) coupled to high-speed photomultiplier tubes, increasing count rate and boosting signal to noise ratios. This enables higher quality images to be obtained with lower tracer dose and quicker scan times, improving patient comfort and decreasing radiation dose. "Scan times have been reduced significantly," notes PET/CT technologist Denise Whelan. "Many of our patients are very ill, and it's difficult for them to lie on the scanner table for extended periods of time, so this is a significant improvement for them."
The detectability of small lesions is enhanced by "Time of Flight", a PET reconstruction technique enabling more accurate localization of tracer uptake in the body, resulting in sharper images. This algorithm is particularly helpful for improving scan quality in larger patients, who can now be accommodated due to the new scanner's weight limit of five hundred pounds.
The CT component of the Discovery 690 is a 64-slice CT with dose reduction software. The higher-slice CT not only scans faster, decreasing motion artifacts, but enables thinner image reconstruction, allowing detailed visualization of small structures and smooth multiplanar reconstructions. The option to perform a diagnostic CT with IV contrast is now be included on PET/CT order forms, as well as the option of a low-dose, nondiagnostic CT for attenuation purposes only. "These options allow us to tailor each exam to the individual patient's (and referring physician's) needs, " states Singha. For instance, an oncologist treating a patient with suspected local recurrence of head and neck carcinoma may order a thin-section, IV contrast-enhanced neck CT as the attenuation component of the PET/CT for optimal visualization of the neck anatomy, whereas a pulmonologist interested in characterizing a solitary pulmonary nodule in a patient with a recent chest CT may order a PET/CT with a low-dose nondiagnostic CT.
Although most PET/CT exams are performed with F-18 fluorodeoxyglucose (FDG) in patients with known or suspected malignancy, cardiac and neurologic applications are anticipated to increase in the future, as well as the use of PET/CT in lieu of a traditional bone scan.
To schedule a PET/CT, please contact Lori Chauvin at (504) 883-8995.