Pulmonary Functional Imaging, Basics and Clinical Application of Nuclear Medicine and Hybrid Imaging

Ventilation/perfusion tomography (V/P SPECT) is recommended as the firsthand tool for diagnosis of pulmonary embolism (PE) based on standardized technology and new holistic interpretation criteria. Pre-test probability helps clinicians to choose the most appropriate objective test for diagnosis or exclusion of PE. Interpretation takes into account all ventilation and perfusion patterns allowing for diagnosis of other cardiopulmonary diseases than PE. In such contexts, V/P SPECT has both an excellent sensitivity and an excellent specificity for detecting PE. V/P SPECT has no contraindication; it is noninvasive and radiation exposure is low. Moreover, acquisition time for V/P SPECT is only 20 min. It allows for quantification of PE extension, which has an impact on individual treatment. It is uniquely useful for a clinical follow-up and for research. Hybrid SPECT/CT imaging is a novel technique primarily developed to improve sensitivity and specificity of oncological diseases. Hybrid SPECT/CT imaging is not recommended as the primary tool for PE diagnosis in all patients with suspected PE. SPECT/CT may be relevant in COPD patients in order to identify small lung tumors and to classify severity of COPD. This is currently under investigation. PET and PET CT or PET MRI are additional imaging techniques that are used to asses and quantify lung function and metabolic changes. Usually most explored biomarker is F-FDG used to show activity of pulmonary inflammation in a variety of respiratory diseases. (Less)