What is assessed in a chest CT scan?
A chest CT scan allows assessment of the lungs — including small changes, such as lung nodules —, the mediastinum (the central region of the chest, between the lungs), the pleura, the chest wall and the bony structures. With dedicated, high-resolution protocols, it allows a detailed study of the lung tissue — useful in interstitial lung disease.
When administered, iodinated contrast allows the mediastinum, the lymph nodes and the vessels to be studied in more detail, according to the clinical indication. The pulmonary vessels and the thoracic aorta are studied by CT angiography, with a dedicated protocol.
CRMA has advanced software for segmentation, measurement and assessment that complements the radiologist's reading: it allows pulmonary emphysema to be quantified — in support of the assessment and follow-up of COPD — and supports the identification, characterisation and follow-up over time of lung nodules, with measurements and comparison between exams. We also carry out virtual bronchoscopy — a three-dimensional reconstruction of the airways from the CT images, which allows the inside of the trachea and bronchi to be travelled through and assessed without any invasive procedure. The report is produced by a radiologist; the clinical interpretation rests with your doctor.
When it is requested
- Characterisation of changes found on a chest X-ray.
- Study and follow-up of lung nodules — with advanced segmentation and assessment software that supports measurements and comparison between exams.
- COPD and emphysema — quantification of emphysema with dedicated software, in support of assessment and follow-up.
- Persistent cough or other respiratory symptoms under investigation.
- Interstitial lung disease — with a high-resolution protocol.
- Suspected respiratory infection or assessment of its complications.
- Pleural conditions — effusion, thickening.
- Staging and follow-up in an oncology setting, according to your doctor's guidance.
- Assessment of the mediastinum and after chest trauma, according to clinical guidance.
What the exam is like
- 1Before
Reception
Arrive 15 minutes early — at least 30 minutes early if the exam includes oral contrast (we let you know when booking). If the exam is with contrast, 4 hours' fasting is required; if you have recent blood tests with kidney function (last 3 to 6 months), it's advisable to bring them.
- 2
Preparation
You remove only the metal objects from the chest area: necklaces, zips, underwired bras, piercings. As a rule, you keep your own clothes on, provided they have no metal parts in the area.
- 3
Positioning
Lying on your back on the table, usually with your arms above your head so they don't interfere with the images.
- 45–10 min
Image acquisition
The table moves through the scanner's open ring. You will be asked to hold your breath for a few seconds during each acquisition — this is the most important thing for image quality.
- 5
Contrast (when indicated)
Iodinated contrast is given intravenously — it is normal to feel a passing warmth and a metallic taste. In some studies, according to the clinical information, oral contrast may also be given — in those cases, we ask you to arrive at least 30 minutes early.
- 6
Finishing
You can leave, drive and resume your normal day. If you received contrast, we recommend drinking water throughout the day.
Preparation
- Fasting: 4 hours, only when the exam is with contrast. Without contrast, fasting is not needed.
- Kidney function: if the exam is with contrast and you have recent blood tests (last 3 to 6 months) with creatinine/kidney function, it's advisable to bring them. They are not mandatory.
- Medication: keep your regular medication — including metformin — unless your doctor advises otherwise.
- Iodinated contrast allergy: if you have had a reaction to iodinated contrast, let us know when booking. Each case is assessed individually by the radiologist.
- Metal objects: remove only those from the area being studied — necklaces, zips, underwired bras, piercings.
- Clothing: as a rule, you keep your own clothes on, provided they have no metal parts in the chest area.
- Breathing: during the exam you will be asked to hold your breath for a few seconds — the radiographer guides you at the time.
- Pregnancy: CT uses X-rays. If you are or think you may be pregnant, always let us know before the exam.
- Breastfeeding: always let us know. If the exam is with contrast, breastfeeding may continue as normal after the contrast is given (ACR/ESUR recommendation).
- Documents: referral, insurer/scheme card (if applicable), previous chest exams (X-ray/CT) and recent blood tests, if you have them.
Results
The report is produced by a radiologist from the images. The report is available as a PDF (by email or printed) and the images on CD and on CRMA's imaging platform, to take to your doctor.
