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Radiographic Procedures And Pathology. Prep Course 1 > CT Module 8 > Flashcards

CT Module 8 Flashcards

1
Q

HOUNDSFIELD UNIT

A

A CT number that represents the attenuating properties or density of each tissue.

  • Water is the reference tissue which is given a value of zero
  • Tissue it’s the highest value will be white
  • Tissue lower than the range will be black
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2
Q

WINDOW LEVEL

A

The CT # of the tissue of interest. Which CT # are displayed on the image

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3
Q

WINDOW WIDTH

A

It determines the gray levels to be displayed in the image.

This can be decreased or increased to produce an image

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4
Q

INCREASE WINDOW WIDTH

A

Wider range of values will be included into the grayscale,

  • the image will have lower contrast
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5
Q

DECREASE WINDOW WIDTH

A

Less range of values included ,

  • Image will have higher contrast
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6
Q

WIDE WINDOW WIDTH

A

More shades of gray with in the lung tissue

  • Longer gray scale

Eg- Lung window WW: 1000, WL:-700

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7
Q

NARROW WINDOW WIDTH

A

Fewer shades of gray resulting into higher contrast image

Eg. Mediastinal window, soft tissue window. WW: 529, WL : 24

Lungs are completely black

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8
Q

PATIENT PREPARATION IN CT

A
  • Verify patient -
  • Briefly explain the procedure
  • Obtain written consent for invasive procedures
  • Describe to the patient how they will be positioned and table movement
  • Provide time frame of procedure
  • Explain what is expected of the patient for the procedure- breathing , no movement etc
  • Describe the type of contrast to be used and it’s purpose
  • Check for allergies if contrast is required
  • Provide lead protection where appropriate
  • Provide post procedural instructions
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9
Q

PUPOSE OF PATIENT HISTORY SHEET

A
  • Patient safety- For contraindications
  • Protocol Selection
  • Clinical information - Help radiologist with diagnosis

-

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10
Q

BUN ( blood Urea nitrogen ) and Serum Creatinine

A

Used to measure patient kidney function

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11
Q

GFR ( glomerular filtration rate)

Normal values

A

120 ml/ min

Contrast will be given for a GFR greater than 30 ml/min

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12
Q

BUN ( blood urea nitrogen)

Normal values

A

7-21 mg/dl

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13
Q

SERUM CREATININE

NORMAL LEVEL

A

Male: 60-120 umol/L

Females: -100 umol/L

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14
Q

BLOODWORK

For Biopsy or drainage patients on warfarin

A

Prothrombin Time PT, Partial thromboplastin Time PTT and Platelet count will be viewed due to the increased risk of bleeding .

  • patients on warfarin , heparin , plavix or aspirin may be instructed to discontinue before the procedure due increased risk of bleeding
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15
Q

aPURPOSE OF CONTRAST MEDIA IN CT

A

To distinguish adjacent structures on a CT image, creating a difference in attenuation values

  • Used in CT to distinguish normal anatomy from pathology and to make various disease processes more visible
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16
Q

POSITIVE CONTRAST MEDIA

A
  • Absorbs more radiation than the surrounding tissues therefore appears white or light on images
  • Has high atomic number
  • Positive Hounsfeild unit
  • Radiopaque
  • Eg Barium #56, Iodine # 53
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17
Q

NEGATIVE CONTRAST MEDIA

A
  • Penetrated by X-rays more than surrounding tissues therefore appears black on images
  • Low atomic number
  • Radiolucent
  • Negative Hounsfeild unit
  • Eg, Air , CO2 and water
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18
Q

aGASTROINTESTINAL POSITIVE CONTRAST MEDIA IN CT

Barium Sulphate is used

A
  • Introduce orally
  • Used to distinguish the stomach, small intestine and large bowel from the surrounding soft tissue organs
  • Only 1-3 % barium suspension is needed in CT due to its greater contrast resolution
  • Patient drinks 450 ml of barium1-2 hours of scan and an addition of 100-200 ml is given just before the scan to fill the oesophagus, stomach and small bowel
  • Contra indication- PERFORATION suspicion - this may cause peritonitis
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19
Q

aGASTROINTESTINAL POSITIVE CONTRAST MEDIA IN CT

WATER SOLUBLE CONTRAST MEDIA ( Gastrografin )

A
  • Indicated for Abdo and pelvis scans when a perforation is suspected
  • Has a bitter taste, often mixed with juice for palatability
  • 2-5 % solutions is utilised in CT
  • Patient drinks 300 ml of water mixed with 25ml of gastrografin
  • Gatrografin is hypertonic thus May causes dehydration
  • very dangerous when administered to elderly, infants or patients that are dehydrated,
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20
Q

GASTROINTESTINAL NEGATIVE CONTRAST MEDIA IN CT

WATER

A
  • Negative contrast media/ enthral neutral

-Causes equal distension in the bowel as barium sulfate

  • Use in clinical practice is increasing
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21
Q

GASTROINTESTINAL NEGATIVE CONTRAST MEDIA IN CT

CO 2

A
  • Radiolucent contrast appears black on images
  • Indicated for virtual colonoscopy exams
  • Rectally administered
  • Small flexible rectal tube is inserted and CO2 is administered via an automated insufflation system
  • CO2 will distend the colon to better visualise polyps
  • CO2 is absorbed in the body and excreted via the lungs
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22
Q

IV CONTRAST MEDIA

A
  • Iodinated water soluble injectable contrast media eg omnipaque/ visipaque
  • Indications to identify tumours, vascular structures, vascular pathology, renal function
  • Two tissues must differ by at least 10 HU to be visibly different on CT scan
  • Administration of contrast media May increase the attenuation difference between adjacent structures by 40-75 HU
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23
Q

CT MEDICAL HISTORY

A

Ask for the following

  • Allergies history
  • Chronic diseases
  • Diabetes
  • Renal dysfunctions
  • Congestive heart failure
  • patient older than 60

If yes to the above questions, patient must have a recent blood test to check Serum Creatinine levels

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24
Q

CONTRASTED CT

FOR PATIENTS TAKING METFORMIN

A

Contrast can be administered

  • if eGFR is below 30mil/ min and contrast was administered, METFORMIN May be withheld 48hrs after the injection
  • If renal dysfunction occurs post contrast METFORMIN could accumulate in the bloodstream and cause lactic acidosis
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25
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

OSMOLARITY

A

The number of particles in solution, unit of liquid as compared to blood

  • Blood osmolarity is 290mOsm/kgwater
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26
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

HIGH OSMOLARITY CONTRAST MEDIA

A

Renografin. Hypaque

  • Solution has 7-8 times the OSMOLARITY of plasma
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27
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

LOW OSMOLARITY CONTRAST MEDIA

A

Omnipaque. Isovue

  • Solution that has 2-3 times the osmolarity of plasma
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28
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

ISO- OSMOLARITY

A

Solution that has equal osmolarity to plasma

Eg. Visipaque

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29
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

aVISCOSITY

A

Thickness of fluid as it flows

  • Viscosity of contrast media affects its injectability
  • Contrast agents can be placed in a warmer to reduce its viscosity making it easier to inject
  • The lose the concentration of iodine atoms within the contrast medium the less viscous the solution
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30
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

IONICITY

A
  • Ionic contrast media will dissociate into 2 charged particles when brought into solution
  • Non ionic contrast media will not dissociate into 2 charged particles when brought into solution. THESE CONTRAST MEDIUMS USUALLY RESULT IN LOWER ADVERSE REACTIONS
  • CONTRAST TODAY IS MOSTLY NON IONIC LOW OSMOLAR, DECREASING ADVERSE EFFECTS, SINCE THEY DONOT INDUCE FLUID IMBALANCE
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31
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

CLEARANCE

A
  • Iodinated contrast media is not metabolised, it is excreted by the kidneys via glomerularfiltration
  • Half life in patients with normal renal function is 2 hours, and cleared 100% in 24 hrs
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32
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

DOSE

A
  • Determined by iodine concentration and volume of solution
  • Contrast Media is measured in milligrams of iodine per lililiter
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33
Q

PROPERTIES OF IODINATED CONTRAST MEDIA

PEDIATRIC DOSE

A
  • asked on weight
  • Common formulae is 2ml per kg
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34
Q

BREASTFEEDING

CONTRAST

A

Less than 1% of contrast media given to mom will be excepted into the breast milk and absorbed by the infant

  • THerefore it is SAFE to breastfeed after receiving iodinated contrast media
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35
Q

VASCULAR ACCESS IN CT

peripheral catheter

A
  • 18-20 gauge Cather preferred
  • Antecubital vein is the preferred site
  • Patency must be confirmed with saline injection prior to hooking up IV line to the injector
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36
Q

VASCULAR ACCESS IN CT

PICC LINE

A
  • Must be a purple PICC line to with stand the injector pressure
  • Must flush with saline after injection
  • Inserted in the cephalic or basilic vein and advanced to the SVC
  • Can remain in place for weeks or months
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37
Q

INJECTOR PARAMETERS

A
  • Volume and concentration of contrast
  • Flow rate
  • Pressure limit
  • Timing between start of injection and start of scan
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38
Q

CT ARTERIAL PHASE

A
  • Arterial structures are filled with contrast
  • Begins immediately after injection
  • AVID ( arteriovenous iodine difference) greater than 30 HU
  • Application CT Angiography
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39
Q

NONEQUILIBRIUM ( Venous) Phase

A
  • Venous and arterial structures are filled with contrast
  • Begin around 60-70 sec post start of injection
  • AVID ( arterial venous iodine difference) 10-30 H
  • Application: Routine body scanning Eg appendix
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40
Q

EQUILIBRIUM ( Delayed ) PHASE

A
  • Organ parenchyma opacified with contrast
  • Begins around 2 min post start of injection
  • AVID ( arterial venous iodine difference) less than 10 HU
  • Application : kidneys
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41
Q

CONTRAST ENHANCEMENT FACTORS

A
  • Injection parameters
  • Condition of patient, particularly the patients cardiac output

NB: Injection protocols are designed by first determining the time during when the contrast material is likely to first arrive in the organ or vessel of interest

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42
Q

AUTOMATIC INJECTION TRIGGERING

A

Two methods

  • test bolus
  • Bolus triggering or tracing
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43
Q

TEST BOLUS

A
  • Obtain scout image
  • Determine target region, and obtain single slice
  • Begin trail scans 8-15 secs after start of injection, scan every 2 sec using low. Ma
  • 10-20ml of CM is injected and several trial scans are taken to determine the length of time from injection to peak contrast enhancement in the target region
  • ROI on vessel
  • Determine scan delay, peak enhancement via graph
  • Trial scan delay + 2 x image @ peak enhancement +3 sec
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44
Q

BOLUS TRIGGERING

A
  • Uses the contrast bolus itself to initiate the scan
  • Obtain scout image
  • Obtain single slice target region. ROI vessel
  • Set trigger thresh hold or watch the graph to begin scan protocol
  • Start the contrast injection, start the low radiation scans 8-10 sec later
  • When the threshold is reached, start scan, the table will move to the start position and scanning begins

NB- A drawback is that a technologist cannot stay with the patient to monitor the injection site

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45
Q

SIDE EFFECTS OF CONTRAST MEDIA ADMINISTRATION

A

Common and predictable=

  • Nausea
  • Vomitting
  • Metallic taste in the mouth
  • Feeling warmth all over
  • Feeling like you have peed your self ( especially4-5 sec post injection )
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46
Q

IDIOSYNCRATIC REACTIONS TO CONTRAST MEDIA ADMINISTRATION

A

These are not predictable, they are allergy like.

  • They present quickly, usually within the first 5-20 min,
  • High risk patients should be monitored for 1 hour after administration
  • Not related to dose, can occur in small amounts being injected
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47
Q

CONTRAST MEDIA

RISK FACTORS

A
  • Patients with multiple allergies to foods and or drugs
  • Patients with asthma
    • Patients who exhibited a reaction to previous contrast administration
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48
Q

CONTRAST MEDIA

PRE TREATMENT

A
  • Un contrasted Ct must be down if possible for high risk iodine reaction patients if possible
  • Pre treatment with Costicosteroids ( prednisone) and or Antihistamine diphenhydramine ( Benadryl) If CT with contrast is deemed necessary
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49
Q

MILD IDIOSYNCRATIC REACTIONS TO CONTRAST MEDIA

A

patient will begin to=

  • Cough
  • Sneeze
  • Nasal congestion
  • Exhibit a rash
  • Itching
  • Urticaria ( Hives)

Treatment =. Benadryl ( Diphenhydramine)

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50
Q

MODERATE TO SEVERE IDIOSYNCRATIC REACTIONS TO

CONTRAST MEDIA

A
  • Dyspnea
  • Wheezing
  • Laryngeal Edema
  • Hypertension or hypotension

Treatment =

  • Oxygen for the Dyspnea
  • Epinephrine for laryngeal Edema
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51
Q

CONTRAST INDUCED NEPHROPATHY. ( CIN)

A

Acute renal dysfunction that occurs after contrast media administration

NB: renal impairment is identified, continuance of the examination should be discussed with the radiologist

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52
Q

RISK FACTORS FOR CONTRAST INDUCED NEPHROPATHY. ( CIN)

A
  • Pre-existing Azotemia
  • Diabetic patients
  • Multiple myeloma patients
  • Patients over 60
  • Administration of more than 200 ml of contrast media in one day
  • Dehydrated patients
  • Concurrent use of nephrotoxic drugs
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53
Q

AZOTEMIA

A

A medical condition in which patient has elevated levels of urea, creatinine, relating to inadequate filtering of blood by kidney

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54
Q

PRETREATMENT/ PREVENTION OF CONTRAST INDUCED NEPHROPATHY. ( CIN)

A
  • Use low osmolar non ionic contrast media
  • Use smallest plume possible
  • Allow 48 hours between procedures requiring CM
  • Prophylactic hydration ( Saline, sodium bicarbonate )
  • Vasodilators
  • Antihistamines ( Benadryl) , Corticosteroids ( Prednisone) to prevent mild reactions
55
Q

CONTRAST MEDIA EXTRAVASATION

A

Contrast media accidentally flowing into the subcutaneous tissue surrounding the vascular system

  • Causes swelling at the site

Common risk factors =

  • Too small cannula for pressure of automatic injector
  • placement of cannula in the hand or wrist area
56
Q

REDUCE RISK OF CONTRAST MEDIA EXTRAVASATION

A
  • Use 18-20 gauge cannula
  • Monitor the injection site
    • Warm the contrast media to reduce the viscosity
  • Use Low Osmolarity Contrast Media ( LOCM)
57
Q

TREATMENT OF CONTRAST MEDIA EXTRAVASATION

A
  • Stop infusion
  • Elavate the affected extremity above the heart
  • Apply cold compress over the injection site for 20 min minimise bleeding
  • Apply warm compress to increase circulation and encourage CM uptake
58
Q

CT HEAD INDICATIONS

A
  • Tumors
  • Circulatory pathology
  • Anteriovenous malformation ( AVM)
  • Inflammatory or injection conditions. (Meningitis , abscess)
  • Degenerative disorder ( atrophy)
  • Trauma
  • Congenital abnormalities
  • Hydrocephalus
59
Q

CT HEAD PATIENT PREP

A
  • Without contrast: No prep
  • With contrast : NPO 2 hours before exam
  • pre and post contrast: NPO 2 hours before exam
60
Q

CT HEAD PRE AND POST

POSITIONING

A
  • Remove metallic items
  • Patient supine on CT bed head first in the Cradle
  • Gantry parallel or angled 15-20 deg to SOML
  • Laser light positioned on the Nasion and EAM

Scout

  • Lateral image of cranium
  • Brain scanned from base to vertex
  • Gangtry is angled so to step and shoot
61
Q

ENHANCED CT HEAD

INDICATION

A
  • Infections/ Abscess
  • Neoplasms
  • AVM ( Ateriovenous malformation)
  • Aneurysm
  • Headaches and seizures

-

62
Q

ENHANCED CT HEAD

CONTRA INDICATEIONS

A
  • Intracranial haemorrhage
  • Early infarction ( stroke)
  • Dementia
  • Hydrocephalus
  • Cerebral trauama
63
Q

CT HEAD SCANNING PARAMETERS

A
  • Small Scanning FOV
  • Display FOV 23cm

Axial slices+

  • Base to vertex
  • 5x 5 mm table increment ( thinner slices can be obtained for more detail)

Windowing =

  • Soft tissue: WW 80. WL: 40
  • Bone: WW 2000 WL 350

Helical Scanning

0,625 x 0,625 mm

IAC, mastoids, sinuses, orbits, CTA

64
Q

CT SINUSES

A

Indication- Sinusitis

  • Scout AP and lateral

Patient positioning =

  • Patient supine with head first in cradle
  • Laser light on Asian and EAM
  • No contrast

Scanning=

  • From hard palate to 1cm above frontal sinuses
  • Helical: 0,625. X 0,625 mm slices
  • Bone Window , Coronal and axial reconstruction
65
Q

CT FACIAL BONES

A

Indication:

  • Trauma

Scout:

  • AP and Lateral

Positioning

  • Patient supine, head first
  • Anatomical Landmark position on Nasion and EAM
  • No contrast

Scanning

  • Topmof frontal sinuses to bottom of mandible
  • Helical: 0,625 mm x 0, 625 mm
  • Bone window reconstruction
66
Q

CT HEAD. CTA

CIRCLE OF WILLIS

A

Indication:

  • Acute stroke
  • Carotid stenosis
  • Carotid dissection

Scout

  • AP and Lateral

Patient position

  • Patient supine, head first
  • Anatomical land mark is nasion and EAM

IV Contrast

  • Test Bolus, ROI on the carotid artery C2 level
  • 320 at 4ml/sec

Scanning

  • Just below C2 to just above vertex
  • Helical
67
Q

BASAL NUCLEI

A

This the gray matter nuclei within the white matter, located bilaterally between the Thalamus and the cortex

68
Q

CAUDATE NUCLEUS

A

C shaped masses that runs along the lateral ventricles

69
Q

LENTIFORM NUCLEUS

A

Large nucleus centrally located in each hemisphere, subdivided into lateral putamen and medial Globus Pallidus

  • Separated from the caudate nucleus by a large tract of white matter called internal capsule
70
Q

CLAUSTRUM

A

Layer of gray matter just lateral to the lentiform. Nucleus and deep to the cortex

71
Q

DIENCEPHALON

A
  • Located in the middle cranial fossa
  • Consists of the Thalamus, hypothalamus and Pineal body
72
Q

THALAMUS

A
  • An oval structure above the midbrain
73
Q

HYPOTHALAMUS

A
  • Located below the thalamus
  • Forms the floor of the third ventricle
  • Connected to the hypothalamus via the infundibulum
74
Q

PINEAL GLAND

A
  • Small gland attached to the posterior portion of the roof of the third ventricle
  • Often calcified
  • Should be seen in the midline, any deviation may indicate a mass
75
Q

MID BRAIN

A
  • Extends from the diencephalon to the pons
  • Located in the posterior cranial fossa
  • Brain stem consists of the. Midbrain, pons and medulla
  • Anterior portion - cerebral peduncles
  • Posterior portion- corpora quadrigemona
76
Q

HIND BRAIN

A
  • Located in the posterior cranial fossa
  • Consists of the pons, Medulla oblong at a and cerebellum
77
Q

PONS

A

Lies directly above the medulla and anterior to the cerebellum

78
Q

MEDULLA

A
  • Continuation of the upper portion of the spinal cord
  • Lies just superior to the foramen magnum
79
Q

CEREBELLUM

A
  • Consists of two hemispheres with the central portion called the vermis
  • Situated in the inferior and posterior portion of the crainial cavity , posterior cranial fossa
  • Separated from the cerebrum by a transverse fissure and a double layer membrane called tentorium cerebell
  • Consists of outer gray ( folia) and inner white ( arbor vita’s)
80
Q

PROTECTION OF THE BRAIN

A
  • Cranium
  • Meninges
  • Spaces( Sunderland, subarachnoid ,cisterns, ventricles)
  • Cerebrospinal fluid
81
Q

FALX CEREBRI

A
  • Extension of dura mater into the longitudinal fissures
  • Attached anteriorly to the crista Gali on the floor of the anterior cranial fossa. Posteriorly attached to the tentorium cerebeli
82
Q

FALX CEREBELLI

A
  • Extension of the dura mater between the cerebella hemispheres
  • Attached superiorly to the tentorium cerebeli and inferiorly to the foramen magnum
83
Q

TENTORIUM CEREBELI

A
  • Located in the transverse fissure, extension between the cerebrum and cerebellum
  • Extends from the occipital protuberance posteriorly to the midbrain anteriorly
84
Q

ARACHNOID VILLI

A

Micro projections in the dural venous sinuses, which returns CSF back to the bloodstream

85
Q

CSF

A
  • Clear liquid that.contains glucose, proteins, lactic acid, urea, cation, anions and lymphocytes
  • Circulates around the brain and spine
  • Volume 80-150 ml ( 3-5oz)
  • Function is protection
  • A medium of exchange of nutrients and waste products
  • Formed by choroid plexus.
86
Q

CHOROID PLEXUS

A

Capillaries in the walls of the ventricles that from CSF

Usually appear calcified on CT

87
Q

VENTRICLES OF THE BRAIN

A
  • Cavities of the brain containing CSF
  • 4 in total .two lateral, one third and one fourth
88
Q

INDICATIONS FOR NECK CT

A
  • Congenital Abnormalities
  • Trauma
  • Infection and abscess
  • Tumors of the pharynx, parotid glands and larynx
89
Q

CT NECK PREP

A
  • Unenhanced ; No prep
  • With contrast: NPO 4 hours before exam, clear fluids are encouraged

IV CONTRAST

  • Used to visualise vascular structures and soft tissue tumours within the neck

Smart prep: ROI in the carotids

ORALCONTRAST

  • maybe administered to distinguish between the oesophagus and surrounding tissue
90
Q

CT NECK POSITIONING

A
  • Patient supine head first into the gantry
  • Laser placed on the nasion and EAM
  • AP and lateral scout
  • Neck is scanned from base of skull ( mid orbit) to thoracic inlet
91
Q

CTA

A

Indications=

  • Acute stroke, carotid stenosis, carotid dissections

Patient positioning=

  • Patient supine head first
  • Landmark Nasion and EAM

Scout

  • AP and Lateral

Contrast

  • 80ml ( 320 at 4 ml/sec)
  • Timing ( test bolus): ROI on aortic arch, scan during arterial phase
92
Q

CT CHEST INDICATIONS

A
  • Mediastinum abnormalities
  • Primary lung tumours
  • Metastatic diseases to the lung
  • Aneurysms
  • Abscess or cysts
  • Cardiac and pericardial diseases
  • Dissection of the aorta
  • Pleural effusion
  • Pneumothorax
  • Pulmonary embolism
93
Q

CT CHEST PATIENT PREP

A
  • Unenhanced: No prep
  • With contrast: NPO 4 hours before exam, clear fluids are encouraged
94
Q

CT CHEST PT POSITIONING

A
  • Patient supine arms elevated feet first
  • Land mark- laser at the sternal notch and axilla

Scout

  • AP and Lateral

Contrast

  • IV contrast media is used to visualise the structures within the mediastinum

Oral

None

95
Q

CT CHEST SCANNING PARAMETERS

A

Mediastinum pathology cases:

  • Chest is scanned from Apices to diaphragm

Pulmonary Malignancies:

  • Scanned from Apices to adrenals, because a number of pulmonary malignancy’s spread to the adrenals
  • Scan FOV ; large. DFV- 38 cm
  • Helical scanning 0,625mm
  • Lung window reconstruction

Lung window

  • Wide contrast scale
  • WW 1500. WL - 700

Mediastinum window

  • Narrow contrast scale
  • WW 400 WL 40
96
Q

HR CT

A

Indication

  • Interstitial tissue. - Pulmonary fibrosis
  • Brochiectasis. - Small airway disease
  • Emphysema

Scout

  • AP and lateral

Patient positioning

  • Supine, feet first
  • No contrast

Scanning

  • Lung Apices to diaphragm on inspiration and expiration
  • Helical slice thickness 1:25mm
  • Bone window reconstruction
97
Q

CT A Chest

A

Indications

  • Dissecting aorta

Scout

  • AP and Lateral

Patient positioning

  • Patient supine, feet first
  • IV contrast

Scanning

  • Above aortic arch to below aortic bifurcation
  • Helical 0,625mm
98
Q

CT PE PROTOCOL

A

Indication

  • Pulmonary Embolism

Scout

  • AP and Lateral

Patient positioning

  • Supine , feet first
  • IV contrast

Scanning

  • Timing run ( test bolus) target slice just below the carina, ROI on pulmonary artery, calculate delay, image with maximum enhancement
  • PE chest series from Apices to diaphragm
99
Q

INTERNAL CAROTID ARTERY

A
  • ascends from the neck, almost in a vertical plane, to enter the base of skull through the carotid canal of the temporal bone
  • The internal carotid has no branches in the neck but branches are in the head to supply blood to the orbit and brain
100
Q

EXTERNAL CAROTID ARTERY

A
  • Ascends the neck , it passes through the parotid gland to the level of the TM joint, where bifurcates into its terminal branches to supply blood to the face and neck

-At it’s lower end it more anterior and medial than the internal carotid

101
Q

RIGHT COMMON CAROTID ARTERY

A

Arises from the brachiocephalic artery posterior to the SC joint

  • Lies medial to the internal jugular vein and birurcate into the internal and external carotid arteries at approximately the level of the thyroid cartilage (C3- C4 )
102
Q

LEFT COMMON CAROTID ARTERY

A

Arises directly from the aortic arch.

-Lies medial to the internal jugular vein and birurcate into the internal and external carotid arteries at approximately the level of the thyroid cartilage (C3- C4 )

103
Q

VERTEBRAL ARTERIES

A
  • Begin as a branch of the subclavian artery and ascend the neck through the transverse foramina of C6- C1, enter the foramen magnum and join to form the basilar artery
  • Vertebral and basilar artery’s supply the posterior aspect of the brain
104
Q

INTERNAL JUGULAR VEINS

A
  • Drain blood from the brain
  • Largest of the vascular structures of the neck
  • Typically runs laterally to the common carotids
  • Runs posterior to the internal carotids
105
Q

EXTERNAL JUGULAR VEINS

A
  • Begin near the angle of mandible and lateral to the Sternocleidomastoid muscle
  • Empties into the subclavian veins
106
Q

BRACHIOCEPHALIC VEINS

A
  • The internal jugular veins commence at the jugular foramen and descend the lateral portion of the neck to unite with subclavian vein to form the brachiocephalic vein
  • The left brachiocephalic vein passes anterior to the left common carotid and right brachiocephalic artery to join the right brachiocephalic vein
  • Left and right brachiocephalic veins join to form the SVC
107
Q

DIAPHRAGM

A
  • A dome shaped muscle that divides the ventral cavity into the thoracic and abdominal cavity
  • The central area is termed the central tendon, and the two halves are called right and left hemi diaphragms

Attachments- XIPHOID Process

                    - Costal cartilages of the last 6 ribs

                    - Lumber Vertebrea via. Crura
108
Q

CRURA

A
  • Tendons attached from the diaphragm to the lumber spine
  • The right crus is longer than the left, to L3. This is due to the force necessary to move the liver down during respiration
  • The shorter left crus extends to L1/ L2
109
Q

OPENINGS OF THE DIAPHRAGM

A
  • IVC - T8
  • ESOPHAGUS. - T10
  • Aotrta, Thoracic duct, Azygous veins. - T12
110
Q

COSTODIAPHRAGMATIC RECESS

A
  • Located at the base of each lung
  • Deepest posteriorly
  • Become smaller on inspiration
  • Clinical significance if patient has excess fluid in the pleural cavity, it will settle in the recess
111
Q

CT ABDOMEN INDICATIONS

A
  • Suspected lesions of the liver, pancreas, kidneys or spleen
  • Fatty liver
  • Adrenal gland pathologic processes
  • Lymph node pathologic process
  • Pancreatitis
  • Abscesses
  • Hematomas
  • Renal stones
  • Hydronephrosis
  • Colon pathologic processes, polyps, Crohn’s disease, ulcerative colitis

Pelvis

  • Prostate ,, cervix , urinarybladder and ovarian carcinomas
  • Soft tissue masses
  • Abscesses
112
Q

Ct ABDOMEN PRE AND POST PREP

A
  • NPO at least 4 hours before exam, clear fluids are encouraged
  • 2 hours before exam drink barium
113
Q

CT KIDNEYS AND PANCREAS PREP

Pre and post

A
  • NPO at least 4 hours before exam, clear fluids are encouraged
  • 1 hour before exam drink 4 cups of water
114
Q

CT KUB PREP

A

No prep

115
Q

CT COLONOGRAPHY BOWEL PREP

A
  • One 4 litre bottle of acolyte to clean out the bowel
  • Contrast is ingested to highlight any stool left in the colon on the virtual colonoscopy images
  • 250ml of Barium
  • 60 ml of Gastrografin
116
Q

BARIUM SULPHATE 1-3%

CT ABDO PREP

A
  • Patient drinks 450ml of barium 1-2 hours,prior to scan
  • An addition 100- 200 ml may be given just before scanning to fill the ESOPHAGUS, stomach and small intestine
117
Q

GASTROGRAFIN 3-5%

CT ABDO PREP

A
  • Patient drinks 300 ml of water mixed with 25 ml of Gastrografin 2 hours prior to the exam
118
Q

CT ABDO PELVIS

PATIENT POSITIONING

A
  • Patient supine, arms elevated above their head, feet fist
  • Landmark laser localiser , placed at the level of the xiphoid process and axilla

Scout

AP AND LATERAL

SCANNING

  • Scan FOV : Large. DFV: 38 cm
  • For abdomen and pelvis scan from diaphragm to symphysis pubis

-

119
Q

UNCONTRASTED CT ABDOMEN

A

Indication:

  • Suspected abdominal mass, tumor staging, abscess

Scout

  • AP and Lateral

Patient Positioning

  • Patient supine, feet first
  • Oral Contrast

Scanning

  • Diaphragm to Symphysis pubis
  • Helical : 0,625mm
  • Coronal and axial reconstruct
120
Q

ENHANCED CT ABDOMEN AND PELVIS

A

Indication:

  • Suspected abdominal mass, tumor staging, abscess

Scout

  • AP and Lateral

Patient Positioning

  • Patient supine, feet first
  • Oral Contrast and IV contrast

Scanning

  • Diaphragm to Symphysis pubis
  • Helical : 0,625mm
  • Coronal and axial reconstruct
121
Q

VIRTUAL COLONOSCOPY

A

Indication:

  • Rectal Polyps, colon cancer

Scout

-AP and lateral

Patient Positioning

  • Patient on
122
Q

INTRAPARETONEAL ORGANS

A
  • Liver
  • Spleen
  • Stomach
    • Small Bowel except Duodenum
  • Cecum, Transverse colon, sigmoid colon and rectum
123
Q

RETROPERITONEAL ORGANS

A
  • Duodenum
  • Pancreas
  • Kidneys and ureters
  • Adrenal glands
  • Descending aorta and IVC
  • 1st apart of the duodenum
  • Ascending and descending colon
124
Q

INFRAPERITONEAL ORGANS

A
  • Urinalysis bladder
  • Ureters
  • Lower part of the rectum
125
Q

MESENTERY

A

Binds the small intestine to the posterior abdominal wall

126
Q

MESOCOLON

A

Binds the large intestine to the posterior abdominal wall

127
Q

GREATER OMENTUM

A

Fatty apron attaches to the stomach and transverse colon and drapes over the small intestine

128
Q

LESSER OMENTUM

A

Fold that suspends the stomach and duodenum from the liver

129
Q

CRURA

A
  • Tendon that attach the diaphragm to the lumber spine
  • The right Crura is longer than the left, extends to L3
  • The shorter left Crura extends to the L1/L2
  • Crura to the diaphragm overlaps anterior to the aorta
  • At T12 the Crura separates to form aortic hiatus
130
Q

ESOPHAGEAL HIATUS

A

Opening in the diaphragm at T10

131
Q

CT VERTEBRAL COLUMN INDICATIONS

A
  • Tumors
  • Inflammatory conditions
  • Degenerative disorders
  • Trauma
132
Q

CT C SPINE POSITIONING

A
  • Patient supine head first
  • No rotation or head tilt
  • Laser at the level of the Nasion and EAM

Scout: AP and Lateral

Scanning:

  • Above the base ok skull to mid T1
  • FOV : Large
  • DFOV: 13 cm
  • No contrast
  • Helical scan
  • Coronal and Sagittal reconstruction

Windows:

Soft tissue : WW: 350. WL: 40. Bone Window: WW: 2000. WL 350

133
Q

CT T SPINE patient positioning

A
  • Patient supine feet first
  • Arms above the head
  • 45 deg sponge under the legs
  • Laser at the sternal notch and axilla

Scout : AP AND LATERAL

Scanning:

  • Above T1 to below T12
  • SFOV : large. DSFOV: 16 cm
  • Bone and soft tissue windows
  • No contrast administrated
  • Helical
  • Coronal and Sagittal reconstruction

Windows

  • Soft tissue: WW: 350. WL 40. Bone Window: WW 2000. WL: 350

Radiographic Procedures And Pathology. Prep Course 1 (18 decks)

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