Nevertheless, there may be a cohort of patients with chronic cough who would benefit from earlier chest CT, potentially leap-frogging weeks of sequential Chronic Cough therapeutic trials that may in fact delay diagnosis. Future research may be needed to evaluate which patients with chronic cough would gain from earlier evaluation with CT. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of FDG-PET/CT in the evaluation of chronic cough with increased risk factors for lung cancer. FDG-PET utilizes a radiolabeled glucose analog to evaluate for upregulated metabolism in areas of infection, inflammation, and neoplasm [43]. It is often utilized in the setting of solitary pulmonary nodules to allow for risk stratification. In the setting of known malignancy, FDG-PET is suitable for staging nodal and metastatic involvement. FDG-PET provides valuable input for further noninvasive testing and operative planning. In patients with chronic cough who have elevated risk factors for lung cancer, it is unlikely that FDG- PET would significantly add value over other imaging modalities, such as chest radiography or chest CT. MRI Chest There is no relevant literature to support the use of thoracic MRI in the evaluation of patients with chronic cough who have increased risk of lung cancer. No studies specific to chronic cough distinguished between contrast- enhanced and noncontrast MRI. In the setting of neoplasm of the chest wall or mediastinum, the addition of extracellular contrast agent would allow for differentiation of cystic and solid features and may add value in planning appropriate invasive testing. Additionally, vasculature is imaged well with the addition of contrast, and contrast-enhanced MRI has been shown to be nearly equivalent to contrast-enhanced CT for the evaluation for pulmonary embolism [29]. MRI was not evaluated in the two prospective clinical series evaluating the utility of a standardized clinical protocol for the evaluation of chronic cough [7,17].
Chronic Cough. Nevertheless, there may be a cohort of patients with chronic cough who would benefit from earlier chest CT, potentially leap-frogging weeks of sequential Chronic Cough therapeutic trials that may in fact delay diagnosis. Future research may be needed to evaluate which patients with chronic cough would gain from earlier evaluation with CT. FDG-PET/CT Skull Base to Mid-Thigh There is no relevant literature to support the use of FDG-PET/CT in the evaluation of chronic cough with increased risk factors for lung cancer. FDG-PET utilizes a radiolabeled glucose analog to evaluate for upregulated metabolism in areas of infection, inflammation, and neoplasm [43]. It is often utilized in the setting of solitary pulmonary nodules to allow for risk stratification. In the setting of known malignancy, FDG-PET is suitable for staging nodal and metastatic involvement. FDG-PET provides valuable input for further noninvasive testing and operative planning. In patients with chronic cough who have elevated risk factors for lung cancer, it is unlikely that FDG- PET would significantly add value over other imaging modalities, such as chest radiography or chest CT. MRI Chest There is no relevant literature to support the use of thoracic MRI in the evaluation of patients with chronic cough who have increased risk of lung cancer. No studies specific to chronic cough distinguished between contrast- enhanced and noncontrast MRI. In the setting of neoplasm of the chest wall or mediastinum, the addition of extracellular contrast agent would allow for differentiation of cystic and solid features and may add value in planning appropriate invasive testing. Additionally, vasculature is imaged well with the addition of contrast, and contrast-enhanced MRI has been shown to be nearly equivalent to contrast-enhanced CT for the evaluation for pulmonary embolism [29]. MRI was not evaluated in the two prospective clinical series evaluating the utility of a standardized clinical protocol for the evaluation of chronic cough [7,17].