Chest MRI
Indications for chest MRI scan
- Assess abnormal growths, including cancer of the lungs or other tissues where MRI offers a
superior alternative to other imaging techniques eg. mediastinal node - For assessment of chest wall tumours, such as sarcoma, osteochondroma, haemangioma, and metastatic tumours of the bone,
- To display lymph nodes and blood vessels, including vascular and lymphatic malformations of the chest
- For assessment of disorders of the bone marrow, such as anaemia and avascular necrosis of the bone
- For assessment of chest wall or diaphragmatic extension of intra thoracic masses
- For assessment of chest and chest wall infections
- Suspected superior sulcus tumour by chest x ray
- Lung cancer staging
- Trauma
Contraindications
- Any electrically, magnetically or mechanically activated implant (e.g. cardiac pacemaker, insulin pump biostimulator, neurostimulator, cochlear implant, and hearing aids)
- Intracranial aneurysm clips (unless made of titanium)
- Pregnancy (risk vs benefit ratio to be assessed)
- Ferromagnetic surgical clips or staples
- Metallic foreign body in the eye
- Metal shrapnel or bullet
Patient preparation for chest MRI scan
- A satisfactory written consent form must be taken from the patient before entering the scanner room
- Ask the patient to remove all metal objects including keys, coins, wallet, cards with magnetic strips, jewellery, hearing aid and hairpins
- Ask the patient to undress and change into a hospital gown
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Instruct the patient to hold their breath for the breath hold scans and breathe gently for the gated scans (it is advisable to coach the patient two to three times before starting the scan) - If possible provide a chaperone for claustrophobic patients (e.g. relative or staff )
- Offer earplugs or headphones, possibly with music for extra comfort
- Explain the procedure to the patient
- Instruct the patient to keep still
- Note down the hight and weight of the patient
Positioning for chest MRI scan
- Position the patient in supine position with head pointing towards the magnet (head first supine)
- Position the patient in the spine,head and neck coil and place the neck and body coil over the neck and chest covering from the tip of the nose down to the lower intercostal border
- Securely tighten the body coil using straps to prevent respiratory artefacts
- Give cushions under the head and legs for extra comfort
- Centre the laser beam localiser over mid chest (i.e. over the nipples)
Recommended Chest MRI Protocols, Parameters, and Planning
Chest MRI Localiser
To localize and plan the sequences, it is essential to acquire a three-plane T2 HASTE localizer initially. These fast single-shot localizers have an acquisition time of under 25 seconds and are highly effective in accurately localizing abdominal structures.
T1 DIXON 3D breath hold coronal 5mm
Plan the coronal slices on the axial localizer and position the block horizontally across the chest as shown. Verify the planning in the other two planes. Establish an appropriate angle in the sagittal plane by aligning it vertically across the chest. The slices must be sufficient to cover the entire chest from the anterior chest wall to the posterior chest wall. The phase direction should be right to left. Additionally, phase oversampling should be used to avoid wraparound artifacts. Instruct the patient to hold their breath during image acquisition. In our department, we instruct patients to breathe in and out twice before giving the ‘breathe in and hold’ instruction.
Parameters
TR 7-8 | TE 2.39 4.77 | FLIP 10 | NXA 1 | SLICE 5 MM | MATRIX 320×320 | FOV 350 | PHASE R>L | OVERSAMPLE 50% | BH YES |
T2 tse\HASTE Multiple breath-hold coronal 6mm
Plan the coronal slices on the axial localizer and position the block horizontally across the chest as shown. Verify the planning in the other two planes. Establish an appropriate angle in the sagittal plane by aligning it vertically across the chest. The slices must be sufficient to cover the entire chest from the anterior chest wall to the posterior chest wall. The phase direction should be right to left. Additionally, phase oversampling should be used to avoid wraparound artifacts. Instruct the patient to hold their breath during image acquisition. In our department, we instruct patients to breathe in and out twice before giving the ‘breathe in and hold’ instruction.
Parameters
TR 5000-7000 | TE 90 | FLIP 150 | NXA 1 | SLICE 6 MM | MATRIX 304×304 | FOV 350 | PHASE R>L | OVERSAMPLE 50% | BH YES |
T1 DIXON 3D axial breath hold 5mm
Plan the axial slices on the coronal image and position the block horizontally across the chest as shown. Verify the planning in the other two planes. Establish an appropriate angle in the sagittal plane by aligning it horizontally across the chest. The slices must cover the whole chest from the mid-neck down to the costophrenic angles (CPA). Instruct the patient to hold their breath during image acquisition. The parallel acquisition technique (IPAT/SENSE) can be used to reduce the scan time. Additionally, adding saturation bands on the top and bottom of the axial block will help reduce arterial pulsation and breathing artifacts.
Parameters
TR 7-8 | TE 2.39 4.77 | FLIP 10 | NXA 1 | SLICE 5 MM | MATRIX 320×320 | FOV 350 | PHASE A>P | OVERSAMPLE 50% | BH YES |
T2 tse\HASTE Multiple breath-hold axial 6mm
Plan the axial slices on the coronal image and position the block horizontally across the chest as shown. Verify the planning in the other two planes. Establish an appropriate angle in the sagittal plane by aligning it horizontally across the chest. The slices must cover the whole chest from the mid-neck down to the costophrenic angles (CPA). Instruct the patient to hold their breath during image acquisition. The parallel acquisition technique (IPAT/SENSE) can be used to reduce the scan time. Additionally, adding saturation bands on the top and bottom of the axial block will help reduce arterial pulsation and breathing artifacts.
Parameters
TR 5000-7000 | TE 90 | FLIP 150 | NXA 1 | SLICE 6 MM | MATRIX 256×256 | FOV 350 | PHASE A>P | OVERSAMPLE 50% | IPAT ON |
T2 tse fat sat\HASTE fat sat Multiple breath-hold axial 6mm
Plan the axial slices on the coronal image and position the block horizontally across the chest as shown. Verify the planning in the other two planes. Establish an appropriate angle in the sagittal plane by aligning it horizontally across the chest. The slices must cover the whole chest from the mid-neck down to the costophrenic angles (CPA). Instruct the patient to hold their breath during image acquisition. The parallel acquisition technique (IPAT/SENSE) can be used to reduce the scan time. Additionally, adding saturation bands on the top and bottom of the axial block will help reduce arterial pulsation and breathing artifacts.
Parameters
TR 6000-8000 | TE 90 | fatsat ON | NXA 1 | SLICE 6 MM | MATRIX 256×256 | FOV 350 | PHASE A>P | OVERSAMPLE 50% | IPAT ON |
T2 tse\HASTE Multiple breath-hold sagittal 7mm
Plan the sagittal slices on the coronal image, positioning the block vertically across the chest as shown. Verify the planning in the other two planes. Establish an appropriate angle in the axial plane by aligning it horizontally across the chest. The slices must cover the chest from right to left. Instruct the patient to hold their breath during image acquisition. The parallel acquisition technique (IPAT/SENSE) can be used to reduce the scan time. Adding saturation bands on the right and left sides of the sagittal block will help reduce arterial pulsation and breathing artifacts
Parameters
TR 6000-7000 | TE 90 | fatsat ON | NXA 1 | SLICE 6 MM | MATRIX 256×256 | FOV 350 | PHASE A>P | OVERSAMPLE 50% | IPAT ON |
For the post-contrast scans, use T1 vibe DIXON axial, sagittal and coronal sequences after the administration of IV gadolinium DTPA injection (copy the planning outlined above).The document below provides access to the recommended dosage of gadolinium DTPA injection, as advised by the manufacturer.
