TY - JOUR T1 - Deep-Inspiration Breath-Hold PET/CT of the Thorax JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 22 LP - 26 VL - 48 IS - 1 AU - Sadek A. Nehmeh AU - Yusuf E. Erdi AU - Gustavo S.P. Meirelles AU - Olivia Squire AU - Steven M. Larson AU - John L. Humm AU - Heiko Schöder Y1 - 2007/01/01 UR - http://jnm.snmjournals.org/content/48/1/22.abstract N2 - The goal of this study was to describe our initial experience with the deep-inspiration breath-hold (DIBH) technique in combined PET/CT of the thorax. This article presents particular emphasis on the technical aspects required for clinical implementation. Methods: In the DIBH technique, the patient is verbally coached and brought to a reproducible deep inspiration breath-hold level. The first “Hold” period, which refers to the CT session, is considered as the reference. This is followed by 9- to 20-s independent breath-hold PET acquisitions. The goal is to correct for respiratory motion artifacts and, consequently, improve the tumor quantitation and localization on the PET/CT images and inflate the lungs for possible improvement in the detection of subcentimeter pulmonary nodules. A physicist monitors and records patient breathing during PET/CT acquisition using a motion tracker. Patient breathing traces obtained during acquisition are examined on the fly to assess the reproducibility of the technique. Results: Data from 8 patients, encompassing 10 lesions, were analyzed. Visual inspection of fused PET/CT images showed improved spatial matching between the 2 modalities, reduced motion artifacts especially in the diaphragm, and increased the measured standardized uptake value (SUV) attributed to reduced motion blurring, as compared with the standard clinical PET/CT images. Conclusion: The practice of DIBH PET/CT is feasible in a clinical setting. With this technique, consistent lung inflation levels are achieved during PET/CT sessions, as judged by both motion tracker and verification of spatial matching between PET and CT images. Breathing-induced motion artifacts are significantly reduced using DIBH compared with free breathing, enabling better target localization and quantitation. The DIBH technique showed an increase in the median SUV by 32.46%, with a range from 4% to 83%, compared with SUVs measured on the clinical images. The median percentage reduction in the PET-to-CT lesions' centroids was 26.6% (range, 3%–50%). ER -