SU-G-IeP4-07: Feasibility of Low Dose 18FDG PET in Pediatric Oncology Patients

• Published in: Medical physics (Lancaster) 2016-06, Vol.43 (6), p.3679-3679
• Main Authors: Zhang, J, Binzel, K, Hall, NC, Natwa, M, Knopp, MI, Knopp, MV
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; Cancer; COMPUTERIZED TOMOGRAPHY; IMAGE PROCESSING; Medical image noise; PATIENTS; PEDIATRICS; Positron emission tomography; RADIATION DOSES; RADIATION PROTECTION AND DOSIMETRY; SIMULATION; Time of flight mass spectrometry; TIME-OF-FLIGHT METHOD; Tissues
• ISSN: 0094-2405; 2473-4209
• DOI: 10.1118/1.4957102

Purpose: To evaluate and demonstrate the feasibility of low dose FDG PET in pediatric oncology patients using virtual dose reduction as well as true patients PET/CT scans. Methods: Wholebody 18F-FDG PET/CT of 39 clinical pediatric patients (0.16±0.06MBq/kg) were scanned on a Gemini TF 64 system at 75±5 min post FDG injection using 3min/bed. Based on the 180s/bed listmode PET data, subsets of total counts in 120s, 90s, 60s, 30s and 15s per bed position were extracted for PET reconstruction to simulate lower dose PET at 2/3th, 1/2th, 1/3th, 1/6th and 1/12th dose levels. PET/CT scans of Jaszczak PET phantom with 6 hot hollow spheres varying with sizes and contrast ratios were performed (real PET versus simulated PET) to validate the methodology of virtual dose PET simulation. Region of interests (ROIs) were placed on lesions and normal anatomical tissues with quantitative and qualitative assessment performed. Significant lower FDG dose PET/CT of 5 research adolescents were scanned to validate the proposal and low dose PET feasibility. Results: Although all lesions are visible on the 1/12th dose PET, overall PET image quality appears to be influenced in a multi-factorial way. 30%–60% dose reduction from current standard of care FDG PET is recommended to maintain equivalent quality and PET quantification. An optimized BMI-based FDG administration is recommended (from 1.1±0.5 mCi for BMI < 18.5 to 4.8±1.5 mCi for BMI > 30). A linear lowest “Dose-BMI” relationship is given. SUVs from 1/12th to full dose PETs were identified as consistent (R2 = 1.08, 0.99, 1.01, 1.00 and 0.98). No significant variances of count density, SUV and SNR were found across certain dose ranges (p