Potential reduction in 123I-MIBG whole body scan time in neuroblastoma patients

533 Objectives 123I-MIBG scans are important for diagnosing and staging neuroblastoma. Image quality can depend on patient cooperation, which is challenging for young patients. This pilot study explored if imaging time can be shortened without loss of diagnostic quality in patients undergoing 123I-MIBG whole body scans. Methods 123I-MIBG whole body scans were acquired with an e.cam camera, medium energy collimator, and scan speed of 8 cm/min. Scans of ten patients age 7-10 y with a known or suspected diagnosis of neuroblastoma and at least 450K counts were studied retrospectively. Mean scan time and anterior counts were 20 min and 672K, respectively. Using Binomial Subsampling to replicate reduced scan time, original 100% time images were processed to 50% time and 30% time. Enhanced Planar Processing (EPP, Siemens Medical Solutions USA) was applied to produce 50% + EPP and 30% + EPP studies. Two nuclear medicine physicians simultaneously rated each of the 50 studies using a 4-point scale (1 = excellent, 4 = poor) based on 4 categories: image quality/artifacts, lesion detection, noise, and image sharpness. These 4 categories were summed for an overall quality score. Data were analyzed using ANOVA with post-hoc analysis (Bonferroni) and Dunnet T-test with 100% time as the control. Results There were no significant differences in overall quality scores with 100% time (4.8 ±0.6), 50% time (5.4 ±0.8), and 50% + EPP (5.3 ±0.9) scans. Lesion detection was consistent in all three, while noise level was less with 50% + EPP (1.1 ±0.3) than with 100% (1.5 ±0.5) or 50% (1.9 ± 0.5). Compared to other times, 30% (6.9 ±1.1), even with EPP (6.8 ±1.0), showed less overall quality (p Conclusions These preliminary results suggest that 123I-MIBG whole body imaging time can be reduced by half (average 10 minutes, scan speed 16 cm/min) without compromising diagnostic quality. Reduced imaging time can improve workflow, patient cooperation, and family satisfaction. Research Support Siemens Medical Solutions USA, Inc