Mid Term Revision Imaging Procedure 3 Dr Mohamed El Safwany, MD.

GOALS OF CT MINIMAL SUPERIMPOSITION IMAGE CONTRAST IMPROVEMENT SMALL TISSUE DIFFERENCE RECORDING

CT MAIN SYSTEMS IMAGING SYSTEM COMPUTER SYSTEM DISPLAY, RECORDING, STORAGE SYSTEM DATA ACQUISITION SYSTEM

COORDINATE SYSTEM IN CT X

Y

Z

ISO-CENTER

PATIENT ORIENTATION HEAD FIRST FEET FIRST

Computed tomography

Soft- tissue

Bone window Computed tomography

Unit controls: –Scanogram AP –Gantry tilt 0º –Slice thickness 7mm –Slice gap 9mm –Soft-tissue (Mediastinal) window –Lung window Computed tomography

Mediastinal window Lung window Computed tomography

Positioning: –Supine and feet first –Arms above the head –The knees flexed 30º Parameters: –Starting at xiphoid process –Ending at the level of hip joint –Respiration suspended in expiration Computed tomography

Unit controls Gantry tilt: 0º. Lateral scout view. Gantry tilt: parallel to the disc space Slice thickness: –3mm Computed tomography

air fat---70 Pure water 0 Csf+8 White matter+30 Gray matter+45 blood+70 Bone/cacification+1000

MCA INFARCT

ACA INFARCT

Old infarct

H’gic infarct

CSF Production Produced in choroid plexus in the lateral ventricles  Foramen of Monroe  IIIrd Ventricle  Acqueduct of Sylvius  IVth Ventricle  Lushka/Magendie cc/min Adult CSF volume is approx. 150 cc’s. Adult CSF production is approx cc’s per day. 25

B is for Blood 1 st decision: Is blood present? 2 nd decision: If so, where is it? 3 rd decision: If so, what effect is it having? 26

Subdural Hematoma Typically falx or sickle-shaped. Crosses sutures, but does not cross midline. Acute subdural is a marker for severe head injury. (Mortality approaches 80%) Chronic subdural usually slow venous bleed and well tolerated. 27

Andrew D. Perron, MD, FACEP CT Scan 28

Intraventricular/ Intraparenchymal Hemorrhage 29

CT Scan Andrew D. Perron, MD, FACEP 30

FRONTAL SINUS CT SINUS AXIAL 31

LENS OF EYE RETRO ORBITAL FAT ETHMOID SINUS MEDIAL RECTUS MUSCLE LATERAL RECTUS MUSCLE CT SINUS AXIAL 32

CT SINUS CORONAL VIEW MAXILLARY SINUS 33 NASAL SEPTUM

ORBIT AXIAL CT RETRORBITAL FAT MEDIAL RECTUS LENS OF EYE LATERAL RECTUS OPTIC NERVE 34

ARTERIOGRAM CAROTID SYPHON OCCIPITAL ARTERY INTERNAL CAROTID ARTERY EXTERNAL CAROTID ARTERY COMMON CAROTID ARTERY MAXILLARY ARTERY MIDDLE CEREBRAL ARTERY ANTERIOR CEREBRAL ARTERY FACIAL ARTERY 35

ANATOMY The pulmonary arteries carry blood from the heart to the lungs. They are the only arteries that carry deoxygenated blood.

INDICATION  Pulmonary embolism  Aortic dissection  Aortic overloading  Left ventricular stress  Teratology of Fallot

CONTRAST DOSAGE  1.2ml /kg (body weight) of non-ionic iodinated contrast medium is injected intravenously into the patient using a pressure injector.  Rate of injection being 4-5 ml /sec  Pressure 325 ppm

PATIENT POSITIONING  Proper breath hold instructions should be given  Ensure the patient connected IV lines, are long enough to allow full travel of the couch without being pulled or entangled while undergoing a CT

 It is a software, that allows real-time monitoring of IV Contrast enhancement in the area of interest. SMART PREP TECHNIQUE

Good Luck