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Updated: Jun 13, 2025

Retrograde Perfusion and Filling of Mouse Coronary Vasculature as Preparation for Micro Computed Tomography Imaging
Published on: February 10, 2012
To PE or Not to PE: Perfusion SPECT/CT Avoids Overdiagnosis
Aamir Ali, Akilan Gopal, Yang Lu1
1From the Department of Nuclear Medicine, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center.
Abstract:
A 41-year-old woman with metastatic breast cancer presented with dyspnea, hypoxia, and elevated d -dimer. Perfusion planar imaging followed by SPECT/CT of the chest was performed due to the patient's iodinated contrast allergy. Planar images showed multiple pleural-based wedge-shaped defects concerning for bilateral pulmonary embolism (PE). Perfusion SPECT/CT of the chest confirmed multiple areas of perfusion defects but was considered negative for PE and attributed the perfusion defects to the compressing of pulmonary vasculature from metastatic lymph nodes and pulmonary masses. Given the high pretest probability of PE, a CT pulmonary angiogram was performed after premedication for contrast allergy confirming absence of PE.
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