thoracic mr imaging - ssr egyptstaging of bronchogenic carcinoma masses/ cysts lymph nodes vessels...
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Thoracic MR Imaging Technical Considerations and Clinical Applications
Mamdouh Mahfouz MD
Prof. of Radiology
Cairo University
www.ssregypt.com
CLOSED MAGNET
CLOSED MAGNET
OPEN MAGNET
EXTERMITY MAGNET
H
H
H
H
H
H
K
H
H
P C
Na
N
H
O
H
H2O
Water represents 75-80% of the human body
O H H
MR Imaging
Magnet
Radio frequency coil
Hydrogen Atom [proton]
H H H H H H H H
MR Imaging
Hydrogen Atom [proton]
H
H
H
H
H
H
H
H
MR Imaging
Hydrogen Atom [proton]
H
H
H
H
H
H
H
H
Adequate Mobile
H
SIGNAL
LOW
HIGH
INTERMEDIATE
DARK, HYPOINTENSE
BRIGHT, HYPERINTENSE
GRAY, ISOINTENSE
MR images depend on the movement of hydrogen protons in response to the applied radiofrequency
Cortical bone
Mature fibrous tissue
Calcifications
Non mobile hydrogen
AIR
Lung &
Sinuses
Minimal hydrogen
H
Amount
Motion Minimal hydrogen [air] → no signal
Non mobile hydrogen [cortical bone] → no signal Fast hydrogen [flowing blood] → no signal
The image will depend on
T2 T1
Air
Cortical bone
Fibrous tissue
Calcifications
Flowing blood
Each structure [lesion] in the human body has a characteristic signal
T2 T1 Subacute blood
Each structure [lesion] in the human body has a characteristic signal
T2 T1 Subacute blood
Each structure [lesion] in the human body has a characteristic signal
T2 T1
T2 T1
Fluid
Fat
T1
T1
T2
T2
Fat
Blood
T1 T2
Small cell lung cancer
CT versus MRI
MR imaging has dramatically changed the practice of medicine
Neurology and orthopedics
Thoracic Imaging
Chest X – ray
Screening,
Emergency medicine,
Intensive care units
CT Scan
MR imaging
Assessment of vascular abnormalities [aorta,
pulmonary arteries, veins, SVC,…]
Evaluation of mediastinal masses
Staging of bronchogenic carcinoma
Diagnosis of chest wall pathology
MAJOR CLINICAL APPLICATIONS
Aortic dissection
Vessels appear usually black due to the signal void of flowing blood
Flow sensitive techniques
Saccular aortic aneurysm
Pulmonary embolism
Bronchogenic carcinoma
chest wall invasion + nodes
Bronchogenic Carcinoma with mediastinal invasion
Bronchogenic Carcinoma , SVC invasion
Superior mediastinal lipoma
Pericardial cyst
T1 T2
Bronchiectasis
سبحانك اللهم و بحمدك نشهد ان ال اله اال انت نستغفرك و نتوب اليك
Thank you
Contrast injection
Modality Item
-
+
CT
MR > CT
Diffuse lung diseases
Focal lung diseases
Staging of bronchogenic carcinoma
Lung parenchyma
• Nodules, miliary shadows CT - • Masses, cysts CT = MR
Contrast injection
Modality Item
-
+
+
-
+ + +
CT
MR > CT
CT = MR
MR ≥ CT
CT = MR
CT≥ MR
MR≥ CT
CT = MR
Diffuse lung diseases
Focal lung diseases
Staging of bronchogenic carcinoma
Masses/ cysts
Lymph nodes
vessels
Hernia and diaphragmatic lesions
Primary lesions
Invasion by lung or mediastinal lesions
Pleural masses and effusion
Lung parenchyma
• Nodules, miliary shadows CT - • Masses, cysts CT = MR +
Mediastinum
• Aorta MR ± • Pulmonary arteries CT = MR ± • Pulmonary veins MR ≥ CT ± • peripheral vessels - (X ray) -
Pleural and chest wall
Contrast injection
Modality Item
-
+
+
-
+ + +
CT
MR > CT
CT = MR
MR ≥ CT
CT = MR
CT≥ MR
MR≥ CT
CT = MR
Diffuse lung diseases
Focal lung diseases
Staging of bronchogenic carcinoma
Masses/ cysts
Lymph nodes
vessels
Hernia and diaphragmatic lesions
Primary lesions
Invasion by lung or mediastinal lesions
Pleural masses and effusion
Lung parenchyma
• Nodules, miliary shadows CT - • Masses, cysts CT = MR +
Mediastinum
• Aorta MR ± • Pulmonary arteries CT = MR ± • Pulmonary veins MR ≥ CT ± • peripheral vessels - (X ray) -
Pleural and chest wall
Intramural hematoma in the descending aorta
MR pulse sequences
T1 weighted images
T2 weighted images
Gradient images
Spin echo images
Fast spin echo images
T1 weighted images with fat suppression
T1 weighted images with contrast [Gd- DTPA]
Molecular O2 enhanced MR imaging
?
THE END
Current applications
Lung cancer
Superior structure tumor
Invasion of vessels [No contrast material]
Mediastinum Pericardium Chest wall [90% sensitivity] Spine
Lymph node deposits
Adrenal metastases
Differentiation of tumors from obstructive atelectasis
Evaluation after surgery or radiotherapy
Aortic dissection
Tumour
Empyema
Bronchogenic carcinoma
invading the pulmonary artery
Bronchogenic carcinoma
Chondrosarcoma of the chest wall
Assessment of chest wall lesions
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