TY - JOUR T1 - Impaired Lung <sup>123</sup>I-MIBG Uptake on SPECT in Pulmonary Emphysema JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1378 LP - 1384 DO - 10.2967/jnumed.111.090076 VL - 52 IS - 9 AU - Kazuyoshi Suga AU - Munemasa Okada AU - Mitsue Kunihiro AU - Osamu Tokuda AU - Hideyuki Iwanaga AU - Naofumi Matsunaga Y1 - 2011/09/01 UR - http://jnm.snmjournals.org/content/52/9/1378.abstract N2 - The aim of this study was to evaluate impaired lung uptake of 123I-metaiodobenzylguanidine (123I-MIBG) on SPECT, compared with perfusion SPECT and morphologic CT, in patients with pulmonary emphysema (PE). Methods: 123I-MIBG SPECT was performed at 15 min and 4 h after intravenous injection of 123I-MIBG in 36 PE patients with a history of smoking and variable-extent low-attenuation areas on CT, indicative of emphysematous changes, and in 16 controls with no history of smoking and no noticeable low-attenuation areas. The distribution of 123I-MIBG was compared with that of low-attenuation areas on CT and perfusion on SPECT at the base of the 180 lung lobes of the PE patients. Total-lung 123I-MIBG kinetics were calculated, including early and delayed lung-to-mediastinum uptake ratios and washout rate. Results: The controls showed a fairly uniform lung 123I-MIBG distribution nearly consistent with perfusion. PE patients had heterogeneous 123I-MIBG defects showing frequent discordance with low-attenuation areas or perfusion distribution; 123I-MIBG defects were more extensive than low-attenuation areas in 76 lobes (42.2%) of 31 patients (86%) and more extensive than perfusion defects in 44 lobes (24.4%) of 22 patients (61%). 123I-MIBG defects were seen regardless of the absence of noticeable low-attenuation areas and perfusion defects in 19 lobes (10.5%) of 16 patients (44%). All total-lung 123I-MIBG kinetic parameters in PE patients were significantly lower than the control values (P &lt; 0.0001), with significant correlation with alveolar–arterial oxygen tension gradient but without correlation with the extent of perfusion defects or low-attenuation areas. Conclusion: 123I-MIBG SPECT allows evaluation of lung pathophysiology in PE independently of perfusion SPECT or morphologic CT, and impairment of lung 123I-MIBG uptake may be more extensive than perfusion or morphologic abnormalities in PE. ER -