title: Vertebral Uptake of Tc-99m Macroaggregated Albumin (MAA) with SPECT/CT Occurring in Superior Vena Cava Obstruction.
abstract: A 67-year-old male presented with dyspnea for which lung scintigraphy was ordered to rule out pulmonary embolus. Planar images demonstrated abnormal midline uptake of Tc-99m macroaggregated albumin, which SPECT/CT localized to several thoracic vertebrae. Thoracic vertebral uptake on perfusion lung scintigraphy was previously described on planar imaging. Radionuclide venography and contrast-enhanced CT subsequently demonstrated superior vena cava (SVC) obstruction with collateralization through the azygous/hemiazygous system and vertebral venous plexus. SPECT/CT differentiated residual esophageal/tracheal ventilation activity, a clinically insignificant finding, from vertebral uptake indicative of SVC obstruction, a potentially life-threatening condition.
authors.affiliation: C02.8711 Nuclear Medicine Department, Royal Victoria Hospital, 1001 Decarie Boulevard, Montréal, Québec H4A 3J1 Canada.
authors.forename: Shawn
authors.initials: S
authors.lastname: Karls
authors.affiliation: C02.8711 Nuclear Medicine Department, Royal Victoria Hospital, 1001 Decarie Boulevard, Montréal, Québec H4A 3J1 Canada.
authors.forename: Hani
authors.initials: H
authors.lastname: Hassoun
authors.affiliation: C02.8711 Nuclear Medicine Department, Royal Victoria Hospital, 1001 Decarie Boulevard, Montréal, Québec H4A 3J1 Canada.
authors.forename: Vilma
authors.initials: V
authors.lastname: Derbekyan
keywords: Collateral circulation; Nuclear medicine; Pulmonary embolism; SPECT; Superior vena cava obstruction; Tc-99m-MAA