Brown Adipose Tissue Uptake Comparison Between Pharmacological and Environmental Control in a Pediatric PET Facility
S Brady*, W Davis, T Holman, S Minderman, L Davis, B Shulkin, St. Jude Children's Research Hospital, Memphis, TNMO-D-141-4 Monday 2:00PM - 3:50PM Room: 141
Purpose: Compare analgesic pharmacology vs. environmental means for controlling FDG uptake in brown adipose tissue (BAT) in a pediatric population with neoplasms.
Methods: For two years (2009-2011) patients were sorted into two groups. (1) patients that required relaxation (Versed) or general anesthesia (Propofol); group one received ~1 hour for uptake in a temperature controlled room before drug administration/scanning. (2) patients were warmed in a temperature controlled room for ~1 hour prior to FDG injection and for ~1 hour after injection. Patient images were evaluated for the presence of BAT: (0) no BAT uptake, (1) Less than uptake in the liver, (2) equal to uptake in the liver, and (3) greater than uptake in the liver. BAT uptake was investigated in the: neck (left and right), axilla (left and right), diaphragm, mediastinum, posterior thorax, and abdomen/pelvis. BAT uptake was considered in a patient with at least one anatomical region with a score > 0. Point biserial correlation, assuming dichotomous data, was calculated to determine statistical significance using a one-sided t-test.
Results: Room temperatures for 623 patients were collected. Mean room temperature over the two years was 74.5° ± 1.3°. A total of 361 patients received sedation/anesthesia drugs. 129 patients were randomly selected; 114 patients (88%) had no BAT uptake and 15 (12%) demonstrated uptake. For group two, 143 patients were randomly selected from the 623. Room temperature for patients with BAT uptake (41%) was 74.4° ± 1.4°, and without BAT uptake (59%) was 75.0° ± 1.1°; a statistically significant difference (t-value was 1.9, critical number was 1.7).
Conclusion: A statistically significant improvement in BAT uptake was found for patients held for one hour in rooms with mean temperatures of 75° prior to FDG injection. BAT was not fully controlled using environmental controls as compared to patients that received analgesic pharmacology.