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Thorax Osteology and Diagnostic

Imaging

• Thorax Osteology (Gray’s pp. 118-126; Gray’s dissector, pp. 49-54)

• Diagnostic Imaging (Gray’s pp.5-11)

-Radiography

*Plain

*Contrast

-Computerized Tomography

-Ultrasonography

-Magnetic Resonance Imaging

-Positive Emission Tomography

Moving From the Back to the Front

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Thoracic Wall

Sternum

Syllabus p. 42

Ribs

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Typical Ribs

Atypical Ribs

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Atypical Ribs

Joints of the Ribs

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Sternum

Scapula (Anterior View)

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Clavicle

Thorax Osteology and Diagnostic

Imaging

• Thorax Osteology (Gray’s pp. 118-126; Gray’s dissector, pp. 49-54)

• Diagnostic Imaging (Gray’s pp.5-11)

-Radiography

*Plain

*Contrast

-Computerized Tomography

-Ultrasonography

-Magnetic Resonance Imaging

-Positive Emission Tomography

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Anatomical position, planes, and

terms of location and orientation

Basic Principles of Radiology

Most Radiolucent -Air- Least Radiodense

-Fat-

-Water and tissue-

Least Radiolucent -Bone- Most Radiodense

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Basic Principles of Radiology

Air = black

Bone = White

Radiologic Nomenclature

• Posteroanterior (PA) radiograph is the

standard view of the thorax or chest

-X-ray’s traverse the patient from posterior

to anterior

• Anteroposterior (AP) is used more

frequently to study vertebrae

-X’ray’s traverse the patient from anterior

to posterior

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PA View

PA View

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AP View

Lateral View

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Abnormal Curvature

Contrast Radiography

• Use reagents that absorb more X-rays to

visualize structures

-Barium Sulfate Suspension – bowel

lumen

-Iodine based reagents are used for intra-

arterial and intra-venous injections

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Contrast Radiography

Contrast Radiography

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Contrast Radiography

Contrast Radiography

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Basic Principles of Computed

Tomography

• Patient lies on a bed, an X-ray tube (CT

scanner) passes around the body and a

series of images (slices) are obtained.

• CT image relates well to classic

radiography (i.e., absorption of X-ray’s)

• CT scans are always displayed as if the

viewer were standing at a supine patient’s

feet.

Computed Tomography

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Computed Tomography

CT Scan

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Basic Principles of Ultrasound

• Delineation of internal structures (i.e. organs) bymeasuring the reflection of ultrasonic waves.

-Doppler ultrasound is used to detect movementof scatters (i.e., red blood cells) by the change infrequency of returning echoes.

• The sound waves bounce back from internalorgans and are interpreted by a powerfulcomputer and a real-time image is displayed onthe panel

Ultrasound

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Ultrasound

Basic Principles of MRI

• MRI is dependent on free protons in thehydrogen molecules of water (H2O)

• Essentially the hydrogen protons serve as barmagnets

• Patient is placed in a strong magnetic field whichaligns bar magnets, radiowaves are pulsedthrough and deflected.

• The strength, frequency and time it takes for theprotons to return to their pre-excited stateproduces a signal that is interpreted by acomputer and an image is displayed

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Basic Principles of MRI

• By altering the sequences of pulses to

which the protons are subjected, the

radiologist can “weight” the scan

-T1 weighted images show dark fluid and

bright fat

-T2 weight images show bright signal from

fluid and an intermediate signal from fat

MRI

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Positive Emission Tomography

• PET is an imaging modality for detecting

positron emitting radionuclides

• FDG is most commonly used PET

radionuclide

PET Imaging

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PET Imaging