CT scans of the chest are a powerful diagnostic tool for pulmonary diseases, offering high-resolution cross-sectional images that can detect abnormalities not visible on conventional chest radiographs. These scans provide detailed visualization of lung parenchyma, airways, pulmonary vessels, mediastinum, pleura, and chest wall structures, allowing clinicians to identify and characterize conditions such as pulmonary nodules, interstitial lung diseases, emphysema, bronchiectasis, pulmonary embolism, and lung cancer. Advanced techniques like high-resolution CT (HRCT) and CT angiography provide specialized applications for specific clinical questions.
| Type | Description | Clinical Applications | Radiation Dose |
|---|---|---|---|
| Standard CT | Conventional CT scan of the chest with 3 mm slice thickness | General evaluation, large masses, pleural disease | Moderate |
| High-Resolution CT (HRCT) | Thin-slice (1-2 mm) imaging optimized for lung detail | Interstitial lung disease, bronchiectasis, emphysema | Low to moderate |
| CT Pulmonary Angiography Protocol (CTPA) | Contrast-enhanced scan timed for pulmonary arterial opacification | Pulmonary embolism, pulmonary vascular disease | Moderate |
| Low-Dose CT | Reduced radiation protocols with acceptable diagnostic quality | Lung cancer screening, follow-up of nodules | Low |
| Ultra-Low-Dose CT | Further radiation reduction using iterative reconstruction | Lung cancer screening in high-risk patients | Very low |
Each type of CT chest scan offers unique advantages for specific clinical scenarios. The selection of the appropriate protocol depends on the diagnostic question, patient characteristics, and the need to balance diagnostic yield with radiation exposure. If you are uncertain, your local radiologist can help you determine the best type of scan to use.
The Atlas of Images – Interstitial Lung Diseases is an educational reference designed to help clinicians recognize, differentiate, and monitor ILDs using high-quality HRCT and radiologic images. It serves as a practical diagnostic aid, highlighting key imaging patterns to improve accuracy and support patient care decisions.
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Developed and published by a pharmaceutical company
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It can be challenging to differentiate honeycombing from bronchiectatic airway changes on CT scans, particularly in the distal lung regions. A key distinguishing feature is that honeycomb cysts maintain relatively consistent dimensions throughout sequential CT slices, whereas bronchiectatic airways demonstrate a characteristic tapering pattern as they extend laterally and peripherally.
Example, from https://radiopaedia.org/cases/cystic-bronchiectasis-10#image-1403876
he outlines of the vessels in this axial view are rearranged, and their tapering proximal-to-distal can be appreciated
This differentiation is important when differentiating ILD phenotypes.