From the Guidelines
A CT chest is being ordered to evaluate for underlying lung pathology not visible on the chest X-ray in a patient with COPD who continues to experience shortness of breath despite recent increase in Trelegy and inconsistent use of prescribed supplemental oxygen. The patient's persistent symptoms, despite medication adjustment, suggest either COPD progression or an alternative/additional diagnosis that requires identification for appropriate management. According to the American College of Radiology 1, chest radiographs can help exclude alternative diagnoses and evaluate for comorbidities and complications in COPD patients, and it is reported that 14% of chest radiographs ordered during COPD evaluation detected potentially treatable causes of dyspnea other than COPD and lung cancer. The CT scan can detect subtle lung abnormalities such as early emphysematous changes, bronchiectasis, interstitial lung disease, small pulmonary nodules, or pulmonary embolism that may be contributing to the patient's persistent symptoms. Some key points to consider when ordering the CT chest include:
- Evaluating for underlying lung pathology not visible on the chest X-ray
- Identifying potential comorbidities or complications that may be contributing to the patient's symptoms
- Guiding treatment decisions, potentially including medication adjustments or further diagnostic testing
- Advising the patient to use their supplemental oxygen as prescribed while awaiting the CT results, as intermittent use may be contributing to symptom persistence.
From the Research
Reason for Ordering a CT Chest
- The patient has COPD and a negative chest X-ray (CXR), but continues to experience shortness of breath (SOB) despite recent increases in treatment and prescribed supplemental oxygen therapy that is not being used consistently.
- A CT chest may be necessary to rule out other potential causes of SOB, such as pulmonary embolism (PE), which can be diagnosed using contrast-enhanced CT scans 2, 3, 4.
- The use of contrast-enhanced CT scans has been shown to be effective in diagnosing PE, with studies demonstrating high sensitivity and specificity 2, 4.
- Additionally, CT chest scans can provide more detailed information about the lungs and surrounding tissues than CXR, which can help identify other potential causes of SOB.
- The choice of CT chest protocol, including the use of contrast medium, can affect image quality and diagnostic accuracy, highlighting the need for standardized protocols and guidelines 5.
- The use of venous-phase CT chest protocols has been shown to be effective in diagnosing PE and other pulmonary diseases, and may be a useful approach in this patient's case 3.