Procedures Flashcards
- Gantry Angle For CT Brain is ______
- Is CT Brain Helical or Axial Scan? Why?
- What Causes Streak Artifacts in a CT Brain? How is this fixed/prevented?
- Parallel to Supraorbital Meante Line (SOML)
- Axial b/c Gantry can’t be tilted & scan in Helical
- Posterior Fossa typically has streak artifacts due to different attenuation between hard skull and soft brain tissue.
- Adjusted by using different slice thicknesses.
- Adjust by increasing kVp
- How is the Posterior Fossa scanned? Why?
- When would you scan a CT Brain in Helical?
- Brain Window Width & Level For:
- Soft Tissue ____ WW & ____ WL
- Posterior Fossa ____ WW & ____ WL
- Blood ____ WW & ____ WL
- 1.25mm thickness to help reduce beam hardening artifacts
- Reduce motion artifacts or 3D post processing is needed
- Brain Window Width & Level For:
- ST = 160 WW & 40 WL
- PF = 100 WW & 30 WL
- Blood = 200 WW & 60 WL
- What type of Window Width is needed for viewing CT Brain? Why?
- How will a hemorrhage appear from onset - 3 days?
- 4-10 days?
- 11 days - 6 months?
- Beyond 6 months? - Clinical Indications for Contrast in CT Brain?
- Narrow Width b/c of slight differences between gray & white matter of brain
- Onset -3 = Hyperdense
- 4-10 days = Hyperdense Center w/ hyper&hypodense surroundings
- 11 Days- 6mo = Isodense Center w/ Hyperdense surroundings
- 6mo+ = Hypodense - Infection, Neoplasm, Venous Malformation
CT BRAIN:
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Gantry to SOML
PREP= NONCON but if CON ~100ml
CLIN= w/o Hematoma, IHA, Infarction, Dementia, Hydrocephalus
- w/ = Infection or Neoplasm
SCAN= Below Skull Base - Above Vertex
ALG.= Soft Tissue & Bone
SLICE= Thin (2-5mm) For Skull Base Through Post. Fossa
- Thick (5mm+) For Post Fossa to Above Vertex
RFMT= SAG, COR, Protocol Dependent
CT FACIAL BONES
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine
PREP= NONCON
CLIN= Facial Trauma
SCAN= Frontal Sinus to below Mandible
ALG.= Soft Tissue & Bone
SLICE= 2mm - 3mm
RFMT= SAG, COR, 3D
CT ORBITS
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Gantry Parallel to IOML
PREP= NONCON, But if ~100ml
CLIN= w/o Trauma, FB
- w/ Mass, Infection, Inflammation
SCAN= Orbital Floors to Orbital Roofs
ALG.= Soft Tissue & Bone
SLICE= 2mm - 3mm
RFMT= COR & SAG
- Oblique maybe for Optic Nerve
CT SINUS’
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= SUPINE
PREP= NONCON, But If ~100ml
CLIN= w/o Sinusitis
- w/ Infection, Mass or Vascular Ab
SCAN= Maxillary & Ethmoidal Sinus through Sphenoid & Frontal
ALG.= Soft Tissue & Bone
SLICE= 2mm - 3mm
RFMT= COR & SAG
- When would Oblique Orbits be requested?
- Facial Bones may require what? (in regards to patient position)
- What reduces need for patient to be prone in CT Sinus’?
- Optic Nerve is ROI
- Open Mouth Scan & Closed Mouth Scan
- MPR removed need for prone or dropped head
- CTA of Brain images what?
- What are the Arteries of Interest in CTA Brain?
- What is typically done prior to a CTA Brain?
- What phase is CTA Brain scanned at? Why is this important?
- Arteries of Brain at peak opacification
- Basilar Artery, Middle Cerebral Artery, & Circle of Willis (COW)
- NONCON Brain CT
- Arterial Phase
- Specific Injection Rate of 4ml/s +
CTA BRAIN
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Antecubital IV
PREP= CON 60-80ml
CLIN= Cerebral Aneurysm, Arterial Stenosis, Malformation
SCAN= C2 to Top of Skull
ALG.= Soft Tissue
SLICE= 1mm-2mm
RFMT= COR, SAG, MIP, 3D
- What is typically done prior to a CT Perfusion Scan?
- What is a Perfusion scan evaluating?
- Goal of Perfusion? - 3 Key Measurements of Perfusion:
- NONCON Brain CT
- Evaluate blood flow in & out of brain tissue.
- Determine infarcted brain tissue vs viable brain tissue - Blood Volume, Blood Flow & Mean Transit Time
- Define:
- Cerebral Blood Volume
- Cerebral Blood Flow
- Mean Transit Time - Perfusion Contrast:
- Amount:
- Rate:
- Time: - What is crucial in perfusion images? Why?
- CBV= Quantity of blood in 100g tissue
- CBF= Quantity blood moves in 100g tissue in 60 seconds
- MTT= Average time takes blood pass through given area - 50 ml/s
- 5.0-7.0ml/s
- For 60 Seconds - Only ROI scanned
- Higher Dose b/c longer scan time
CT PERFUSION
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Antecubital IV
PREP= CON 50ml,
- Xenon / Xe per protocol
CLIN= Stroke, Vasoplasm, Temporary Occlusion
SCAN= Only ROI (Typically COW)
ALG.= Soft Tissue
SLICE= 3mm - 5mm
RFMT= COR, SAG, 3D, FLOW MAPS
- What type of scan is CT Neck scanned in?
- CT Neck patient positioning considerations?
- Why do you preform Valsalva & “eee” ?
- Helical
- Extend neck up
- lower shoulder much possible
- Valsalva or “eee” - Valsalva = Pyriform Sinus
- eee = Areyepiglottis & Pyriform
CT LARYNX
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Gantry Parallel Vocal Cords
PREP= CON 80-135ml @45-90sec delay
CLIN= Mass, Cyst, Infection, Vocal Cord Damage
SCAN= Mid Orbits To Clavicles
ALG.= Soft Tissue
SLICE= 1mm - 2mm
RFMT= COR & SAG
- How is the gantry positioned in CT Soft Tissue Neck? Why?
- What are typical patient instructions during CT Soft Tissue Neck? Why?
- What Organ/Anatomy is important consideration in CT STN & Why?
- Orbits to Hard Palet = Gantry parallel to hard palette
- Rest of scan = parallel to mandible body
- This prevents streak artifacts - Stop Swallowing & Breathe Softly
- Reduce patient motion - Thyroid Gland
- Hyperdense / important consideration w. contrast
CT SOFT TISSUE NECK
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine
PREP= CON 80-125ml @ 45-90sec delay
CLIN= Mass, Cyst, Infection, Swollen Glands
SCAN= Mid Orbits to Clavicles
ALG.= Soft Tissue
SLICE= 2mm - 3 mm
RFMT= SAG & COR
CTA NECK
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Antecubital Right Arm
PREP= CON 60-80ml @SP 15-18sec
CLIN= Aneurysm, Vascular Injury, Occlusion, Arterial Stenosis
SCAN= Skull Base to Aortic Arch
ALG.= Soft Tissue
SLICE= 1 - 1.5 mm
RFMT= COR, SAG & MIP
- What phase is CTA Neck scanned?
- Why is this important? - What’s done before CTA Neck?
- Contrast injection rate, amount & typical delay for CTA Neck?
- Arterial enhancement of carotid arteries
- Important for injection rate 4.0+ and time being boils tracked 13-18sec - NONCON Neck
- 60-80ml @ 4.0ml/s @ Bolus Tracking but typically 13-18 sec empiric delay
- Where is the IV best placed for CTA Neck? Why?
- Describe C-Spine Anatomy
- Where does the spinal cord begin & end? What is the name of it?
- Right Antecubital
- Reduce streak artifact from contrast entering vasculatures - Between C1 & C2 there’s no intervertebral disc space
- C2 - C7 there is - Medulla of brain to level of L1
- Tapers off into bundle nerves called Cauda Equina
- What does intervertebral disc consist of?
- What is
- Spondylosis
- Spondylolysis
- Spondylothesis - What is spinal Stenosis?
- Nucleus Pulpous - Center of disc
- Anulus Fibrosis - Outer portion of disc - Losis = Hypertophy of
- Lolysis = Damage to interarticularis
- Lothesis = Superior body slips over inferior - Narrowing of spinal cord
CT CERVICAL SPINE
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Head First,
PREP= NONCON, But if 80-100ml @1-3ml/s (Portal Venous Phase)
CLIN= Herniated Disc, Trauma, Lesion, Degeneration, Infection, Post Op
SCAN= Skull Base to T1
ALG.= Soft Tissue & Bone Window
SLICE= .5 mm - 2.0 mm
RFMT= COR, SAG, 3D
- Typical rate of contrast for CT Spine studies?
- What Phase? - What is HNP?
- What are clinical indications for CT Spines?
- 1-3ml/s
- Portal Venous Phase - Herniated Nucleus Propos. (Herniated disc / nucleus protruding)
- HNP, Trauma, Fracture, Post-Op, Degenerative Diseases (Spondies), Lesion, Infections
CT THORACIC SPINE
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Over Head
PREP= NONCON but if 80-100ml @1-3ml/s @ Portal Venous
CLIN= Trauma, Fx, Degenerative, Post Op
SCAN= C7 to L1
ALG.= Soft Tissue & Bone Window
SLICE= 2mm - 5mm
RFMT= COR, SAG, 3D
CT LUMBAR SPINE
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Over Head, Knees Bent
PREP= NONCON but if 80-100ml @1-3ml/s @ Portal Venous
CLIN= Trauma, Fx, Degenerative, Post Op
SCAN= T12 Through L5
ALG.= Soft Tissue & Bone Window
SLICE= 2mm - 5mm
RFMT= COR, SAG, 3D
- What is different about CT Lumbar positioning vs C & T Spine?
2 Why are Breath Holds used in CT Chest exams?
- Common site for Metastesses?
- C & T =. Head First
- L = Feet First & Cushion for bent knees to relieve low back pain
T & L = Arms Raised - Reduce motion artifacts
- Adrenal Glands
- How is a CT Chest typically scanned?
- Why? - Contrast rate & amount for CT Chest?
- Cardiac Exams Ideal HR?
- Inferior to Superior to reduce contrast artifacts as it is injected
- 70-120 ml @ 2-4ml/s
- Below 65 BPM
CT CHEST
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised
PREP= CON 70-120ml @ 2-4ml/s,
Breath Holds
CLIN= Mass, Infection, Emphysema, Congenital Thoracic Cond. Abnormal XRays
SCAN= Above Apices to below lung base / diaphragm
ALG.= Soft Tissue & Lung Window
SLICE= 2mm - 5mm
RFMT= COR & SAG
CT CHEST (HIGH RESOLUTION)
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine or Prone, Arms Raised
PREP= NONCON, Breathhold, Insp & Exp
CLIN= Asthma, COPD, Cystic Fibrosis, Emphysema, Bronchitis
SCAN= Above Apices through Lung Bases
ALG.= Soft Tissue & Lung Window
SLICE= .5mm - 2mm
RFMT= COR, SAG, MIP, MinIP
- What are patient instructions in High Resolution CT Chest?
- Why? - How is a CT Chest High Res. Scanned?
- What are the Recons in & Why? - What is patient position in CT Chest High Res?
- Why?
- Inspiration & Expiration
- Displace air trapped in patients - Axially w/ Thin Slices (.5-2mm)
- Recon in 10-15mm to better demonstrate interstanial lung disease - Supine & Prone
- Demonstrate Edematous Changes
- Describe Steps of Blood Flow Through Heart.
- Which Side is Oxygenated?
- Superior Vena Cava or Inferior Vena Cava -> 2. Right Atrium -> Tricuspid Valve -> Right Ventricle -> Pulmonary Artery -> Lungs -> Left Atrium -> Mitrial/Bicuspid Valve -> Left Ventricle -> Aorta -> Rest of Body
- LEFT SIDE = Oxygenated (LOX)
RIGHT SIDE = Deoxygenated
- What is commonly used in CT Cardiac Exams?
- What branches off of the RIGHT Coronary Artery?
How Remember - What about the Left?
How Remember
1 ECG Gating
- Conus Artery, Sinus Node Artery, R. Atrial & Ventricle Branches, Posterior Descending Artery
**RIGHT C.A.P = Conus, Sinus, Posterior - Left Anterior Descending Artery & Left Circumflex Artery
** LEFT LAC = Anterior & Circumflex
- What medications are used in CT Cardiacs?
- Why? - What advantages do newer CT Scanners have?
- Why are they important? - What phase of Cardiac Cycle is scanned in CT Cardiacs?
- Why?
- Beta Blockers = Lower HR
- Nitroglycerin = Dilate Vessels - Higher Temporal & Spatial Resolution
Temporal = Clearer images of object in motion
Spatial = Differentiation between structures close together - Diastolic / Rest
- Eliminate Cardiac Motion
- Temporal Resolution =
- Spatial Resolution = - What helps reduce patient dose in Cardiac Exams?
- When are images acquired for Cardiacs?
- What % ECG Interval is used for Cardiac Scan?
- Temporal = Ability produce clearer images of objects in Motion
- Spatial = Allows differentiation between structures close together - Radiation shut off when not in diastolic phase of cycle
- Images acquire through whole cycle, only portion is used for reconstruction
- 55-75% of R-R Interval
CT CARDIAC (Coronary Arteries)
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Antecub IV, ECG
PREP= CON 80-100ml @ 4-7ml/s, Breathholds & Meds
CLIN= Cardiac Abnorm, Calcification, Morphology, Myocardial Perfusion
SCAN= Carina through Apex Heart
ALG.= Soft Tissue
SLICE= 0.4mm - 0.7mm
RFMT= COR, SAG, MIP, 3D, VR, SSD
CT CARDIAC - Calcium Score
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised, ECG
PREP= NONCON
CLIN= Atherosclerotic Disease
SCAN= Carina through Apex Heart
ALG.= Soft Tissue
SLICE= 2mm - 3mm
RFMT= COR, SAG, 3D
- CT Calcium Score evaluates what?
- Why does Calcium Score use ECG?
- Is CT Calcium Score High Dose or Low Dose?
- Calcification of Coronary Arteries
- Monitor Cardiac Cycle for Diastolic phase
- reduce patient dose & limit motion artifacts - Lower Rad Dose
- What defines “Calcification” of Coronary Arteries?
- What’s the Calcium Score Measurement System Called?
- What Are The Ranges for Calcification?
- 1mm^2 with HU above 130
- Agatston Scoring System
- 1-10 Minimal
11-100 Mild
101-400 Moderate
400+ Excessive
- What Breathing Is Used for CT Pulmonary Angiography?
- Why? - How is CT Pulmonary Angiography scanned?
- Why? - Goal of CT Pulmonary Angiography?
- How is it done? - Why is Saline Flush after CTA Pulm good?
- Shallow Breathing or Hold Breath
Shallow Better b/c hold can trap non-opacified blood in arteries and dilute contrast - Caudicranial
- Reduce motion artifacts from patient breathing & reduce artifacts from contrast as it’s being administered - Image Pulmonary Arteries at Peak Opacification
- By Bolus Tracking and Rate of 4.0+ - Saline Flush after to help reduce streak artifacts in Superior Vena Cava
CT PULMONARY ANGIOGRAPHY
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Above
PREP= CON 80-130ml @4.0+, Breathhold or Shallow Breathing
CLIN= Pulmonary Embolism
SCAN= Above Apices to below Lung Bases
ALG.= Soft Tissue & Lung Window
SLICE= .5mm - 2mm
RFMT= COR, SAG, MIP, 3D
CTA AORTA
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Right Antecubital IV, (CAN be gated)
PREP= CON 80-130ml @4.0+
CLIN= Trauma, Aneurism, Dissection, Vascular Abnormal, Arterial Disease
SCAN= Above Clavicles to Below Celiac Arteries
ALG.= Soft Tissue
SLICE= .5mm - 2mm
RFMT= COR, SAG, MIP, 3D, VR
- Goal of CTA Aorta?
- How is it done? - Why should ECG be used in CTA Aorta?
- Where is IV best placed for CTA Aorta?
- Why?
- Imaging peak opacification of Thoracic Aorta
- Rate of 4.0+ - Reduce motion artifacts in aorta
- Right Antecubital
- Reduce streak artifacts appearing in branches of aortic arch
- What are the types of Dissection?
- Explain difference - What is a “Triple Rule Out” for CTA?
- A Type Dissection = Ascending Aorta
- B Type = Descending Aorta - Asses Coronary Arteries, Aorta & Pulmonary Artery
- GI Tract Consists of:
- Where is the Appendix located?
- How is the intestine wall imaged?
- Examples of?
- Esophagus, Intestine & S/L Intestine
- Extends from Cecum by ileocecal Valve
- Oral Contrast
- Water, Barium & Water Soluble Iodine
- First Part of GI Tract is:
- Connects to: - Why is imaging intestine wall important?
- Typical Oral Contrast for CT Abdomen?
1 Esophagus
- To Stomach
- Most pathology contained there
- 750-1500ml
- What determines how long after oral contrast is consumed to scan? (Delay Time)
- Common Ranges: - The Stomach Connects to ______ via ______
- Common Indications for CT of esophagus & stomach?
- Region of Interest & Department Protocol
- Immediate - 3 Hours - Small Intestine via Pyloric Sphincter & Duodbulb
- FB, Esophageal Varies, Hiatal Hernia, Cancer
- The Small Intestine consist of:
- Most Distal Part of Small Intestine is ______
- Why is this important? - Common Small Intestine Indications:
- Duodenum, Jejunum & Illeum
- Illeum
- Where connects to Large Intestine via Ileocecal Valve - Hernia, Obstruction, Intussception, Ileus, Chrohns & Cancer
- The Large intestine consist of:
- Clinical Indications for CT Large Intestine:
- What is the patient prep instructions for CT Abdomen & Pelvis?
- Cecum, Ascending Colon, Transverse Colon, Descending Colon, Sigmoid Colon & Rectum
- Diverticulitis, Inflammatory Bowel, Colitis, Appendicitis
- Some may need NPO 2-8 Hours Prior (Department Based)
- What indicates Appendicitis?
- Four Types of Hernia In Abdomen:
- What Region of Interest for Each - Why do patients fast before CT Abdomen/Pelvis with contrast?
- Inflamed & Thickened Appendix Wall or Presence of Appendicolith
- Hiatal = Esophagus
- Inguinal, Umbilical & Incisional = Small Intestine - Better evaluation of proximal GI & minimize risk of aspiration
- How much contrast is used if distal large colon is area of interest?
- Type & Route? - What can IV Contrast show in intestinal walls?
- Common injection Rate for CT Abdomen/Pelvis?
- Amount & Phase?
- 200ml Positive Contrast (Barium) via Enema
- Wall Thickening, Lesions, Inflammation & Ischemia
- 1.5 ml - 4.0 ml
- 80-120ml
- Portal Venous Phase
CT ABDOMEN / PELVIS
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised
PREP= CON 80-120ml IV &/or 750-1500ml Oral, Breathholds
CLIN= Trauma, Mass, Infection, Abscess, Inflammation, RLQ Pain
SCAN= Above Diaphragm through Public Symphysis
ALG.= Soft Tissue
SLICE= 2mm - 5mm
RFMT= COR, SAG, 3D
CT ADRENAL GLANDS
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised
PREP= CON 80-120ml via IV, Breathhold
CLIN= Mass, Lesion, Cancer Staging
SCAN= Slightly Above Diaphragm to slightly below Kidneys
ALG.= Soft Tissue
SLICE= 2mm-5mm
RFMT= COR & SAG
- How is CT Adrenal Gland Typically Scanned?
- Where are Adrenal glands found?
- Why is IV Contrast important in CT Adrenal Glands?
- 2 Aquisitions @ 2 Phases
- Portal Venous Phase
- Delay Phase (10-15 Min)
2 Superior to each kidney / can be seen on routine A/P
- Differentiate between metastatic & benign masses
- Is contrast used in CT Liver?
- Why or Why Not? - How Does Tumor Appear in Liver?
- How does contrast affect this? - How is a CT Liver scanned?
- Why?
- Usually, Based on Department Protocol
- Aids in Diagnosis & Helps Classify Tumors in Liver - Hypo or Hyper dense compared to surroundings.
- Makes them appear isodense - Triple Phase
-1. Early Arterial (15-18sec post Contrast)
-2. Arterial (25-35sec post)
-3. Portal Venous (60-70sec post)
- Properly identify pathology and tumor
- Common Pathology & Tumors of Liver Consist of:
- How is blood supplied to liver?
- Typical CT Liver rate of injection?
- Hepatic Cyst, Hepato Carcinoma, Hemagomia, Fatty Liver, Cirrohos
- Dual Source - 75% Portal & 25% Arterial
- 4.0 ml/s
- Four Phases of CT Liver, There Typical Timing & What is Imaged:
- What Determines CT Liver Delay Timing?
- How Long For Liver Reach Equilibrium?
- Early Arterial - 15 - 20 sec post inj. - Parenchyma minimally enhanced
- Arterial - 25-30sec post inj. -
- Portal Venous - 60-70sec post - Hypovascular Lesions b/c contrast has distributed
- Delayed - 5-15 Min Post - Show Hemogina becoming Isodense - Patient Cardiac Output, Rate Injection, Iodine Concentration
- 2-3 Minutes Post Inj.
- Typical CT Liver Protocol Includes:
- Billary Tract Consist of:
- What other Organ Can Be Seen on CT Liver?
- What would be diagnosed here?
- Pre
- Early / Arterial Contrast
- Portal Venous
- Delay - Common Hepatic Duct, Common Bile Duct, Intrahepatic Bile Duct
- Gallbladder
- Gallstones & Cholecystitis
CT LIVER
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= SUPINE, Arms Raised
PREP= CON 750-1500ml Oral &/or 80-135ml IV, Breathhold
CLIN= Cirrhosis, Infection, Mass, Cyst, Cancer Staging, Pre-Transplant
SCAN= Top of Diaphragm to Illiac Crest
ALG.= Soft Tissue
SLICE= 2mm - 5mm
RFMT= COR, SAG, 3D
- Typical Phase of CT Pancreas?
- Why - What are the steps of CT Pancreas?
- What may occur if CT Pancreas is positive for Pancreatic Cancer?
- Delayed Arterial (35-45sec)
- Parenchyma @ Peak Enhanced
- Allows Pancreas’s neoplasms be identified - Pre Con, Delayed Arterial & Portal Venous TRIPLE PHASE STUDY
- Whipple Reconstruction of Pancreas and Duodum
CT PANCREAS
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised, Antecubital IV
PREP= CON 80-125 ml
CLIN= Pancreatitis, Cyst, Masses/Tumor
SCAN= Diaphragm to Illiac Crest
ALG.= Soft Tissue
SLICE= 1mm - 3mm
RFMT= COR & SAG
- Structures Evaluated in CT Pelvis?
- Is CT best imaging for male & female reproductive organs?
- why/why not?
- What is shown for each? - How does Uterus appear on CT?
- Colon, Bladder, Reproductive Organs
- Not for men b/c they are external but CT can show prostate cancer
- Women yes - Fallopian, Ovaries & Uterus imaged - Homogenous mass between rectum & Bladder
- Describe Uterus location & anatomy:
- Which part(s) of uterus are affected by contrast?
- why? - What is the “Adnexa” of Uterus?
- Between Rectum & Bladder
- 3 Layers: Outer (Perimetrium), Middle (Myometeium) & Inner (Endmetrium) - Myometrium & Cervix
- b/c Vascular nature - Ovaries & Fallopian Tubes
CT PELVIS
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised
PREP= CON Oral (750-1500ml) &/or IV (80-120ml), Breathhold
CLIN= Trauma, Mass, Cancer Staging, Infection, Fibrosis, Cystic
SCAN= Top Iliac Crest Through Pubis Symph
ALG.= Soft Tissue & Bone Window
SLICE= 2mm - 3mm
RFMT= COR, SAG, 3D
- How do ovaries appear on CT Pelvis?
- Is Oral or IV Contrast used for CT Pelvis?
- Amount? - Most common organ affected from Abdomen Trauma?
- Soft Tissue or Cyst- Like Density
- Oral &/or IV or Dry depending rule out
Oral = 750-1500 ml
IV = 80-125ml - Spleen
- What Phase is CT Spleen Scanned?
- Urinary Tract Consist of:
- What is Gerota Fascia?
- Portal Venous
- Kidney, Ureter & Bladder
- Connective tissue around kidney
CT Spleen
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised
PREP= ORAL 750-1500ml &/OR IV 80-125, Breathhold
CLIN= Trauma, Mass
SCAN= Top Diaphragm to Below Pubic Symph
ALG.= Soft Tissue
SLICE= 2mm - 5mm
RFMT= COR & SAG
- Where is a common place for infection/mass/trauma in CT Urinary Tract?
- CT For Kidney Stones is Typically Contrast or No Contrast?
- What might you instruct patient to do prior to CT Urinary Tract exam?
- Calculi
- NONCONTRAST
- Hydrate before exam
- Minimize chance of hyperintensities to appear in renal pyramids
- Contrast in CT Urinary Tract is best for what pathology?
- What 3 phases can be imaged for a CT Urinary Tract exam?
- Timing / Delay?
- What Does Each Show?
- Renal Cyst, Polystic Kidney Disease, Lesions, Carcinomas & Metastasis
- Corticomedullary - 30-40sec post IV, Best for Renal Cortex & Renal Veins
- Nephrographi - 70-90sec post IV, Best for Parenychema & Liver
- Excretory - Min. 3min post IV, Best for Renal Pelvis, Ureters & Bladder
- Why may a prone scan be needed for CT Urinary Tract?
- Multiphase Scanning of Urinary Tact show pathologies such as:
- Based on protocol, what could be the 5 phases of a CT Urinary Tract exam?
- Help differentiate stones in urinary tract
- Dual Collecting System, Obstructions, Tumors & Filing Defects
- Pre Con, Arterial, Corticomedullary, Nephrographic & Excretory
CT URINARY TRACT
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised, May Need Prone
PREP= CON 80-120ml, Oral (Water), Breathhold
CLIN= Kidney Stones, Carcinoma, Cysts, Hydronephrosis, Hematuria, Cancer Staging
SCAN= Above Diaphragm to Below Pubic Symp
ALG.= Soft Tissue
SLICE= 1mm - 3mm
RFMT= COR, SAG, MIP, 3D
- What is a CT Colonography?
- Why are the done? - What is patient prep for CT Colonography?
- Why do patients receive oral Barium& Oral Iodine contrast for CT Colonography?
- Screening Exam for polyps or malignancy, or failed colonoscopy
2.Liquid Only Diet for Days prior, Bowel Emptying Medications, Oral Barium&Oral IV contrast ingested
- MAY need CO2 or Room Air
- Coats stool, fluid & polyps
- Helps differentiate between above 3
- Why is Room Air &/or CO2 Administered for CT Colonography
- How is it Administered?
- Best Way to / Why? - How is patient laying for CT Colonography scan?
- why?
- Allows for better distention
- Through catheter manually or automatic, While patient is in lateral decubitus position
- Automatic = Allows better distention & less chance for perf - Typically supine, but can be prone.
- Helps differentiate between polyps, stool & fluids.
- Prone Promotes Distention
CT COLONOGRAPHY
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine &/or Prone
PREP= ORAL CONTRAST, Rectal via Catheter, Breathhold
CLIN= Polyps, Cancer Staging, Failed Colonoscopy
SCAN= Diaphragm to Below Pubic Symph
ALG.= Lung Window
SLICE= 1mm - 2mm
RFMT= COR, SAG, 3D, “FLY THROUGH”
- What is CT Entercolysis?
- In CT Entercolysis, What’s the Type of Contrast Used, Amount & Route?
- What Phase is scanned for CT Entercolysis?
- Nasogastric Catheter placed in Duodenum using fluoro guidance to evaluate small bowels
- 1-2 liters of Enteral or Neutral Contrast, Via Nasogastric Catheter into Small Intestine
- IV Contrast, 4.0+ ml/s, 40-50 Emperic Delay - Portal Venous via IV of 4.0+ Rate & 40-50 Emperic Delay
CT ENTERCOLYSIS
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised
PREP= CON 80-120 IV & Oral via Nasogastric Catheter
CLIN= Mass, Obstruction, Chrohns
SCAN= Diaphragm to Below Pubic Symph
ALG.= Soft Tissue
SLICE= 2mm - 5mm
RFMT= COR & SAG
CT ENTEROGRAPHY
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised, Antecubital IV
PREP= Oral - 1500ml Low Density Barium & 80-120ml IV, Breathhold
CLIN= Mass, Obstruction, Chrohns
SCAN= Above Diaphragm to Below Pubic Symph
ALG.= Soft Tissue
SLICE= 2mm - 5mm
RFMT= COR & SAG
- Difference between CT Enterography & CT Entercolysis?
- How much Oral contrast is used in CT Enterography?
- Type & Delay? - How much IV Contrast used for CT Entrrography?
- Rate & Delay?
- Enterography = Oral
Entercolysis = NG TUBE - 1500ml Low Density Barium 60-90 min before scan
- 80-120 ml IV @ Rate of 4.0+
- 40-50 sec Emperic Delay for Portal Venous Phase
- Goal of CTA Abdomen & Pelvis?
- What is images - Rate & Delay for CTA Abdomen & Pelvis
- What Phase(s) are scanned in CTA ABDOMEN & PELVIS
- Image Aorta @ Peak Opacification
- Aorta & its branches though abdomen & pelvis - 4.0 + Bolus Tracking
- Pre Contrast, Arterial & Venous
CTA ABDOMEN & PELVIS
1. Renal Arteries images for:
2. Superior & Inferior Mesenteric Arteries & Veins for:
3. Other organs imaged:
- Stenosis, Aneurism & Transplant
- Mesenteric Ischemia or GI Bleed
- Left Gastric, Common Hepatic, & Splenic Arteries
CTA ABDOMEN & PELVIS
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, Arms Raised, Antecub IV
PREP= COM 80-120ml @4.0 Rate, Breathhold
CLIN= Anyuerism, Dissection, GI Bleed
SCAN= Above Diaphragm to below Pubic Symph
ALG.= Soft Tissue
SLICE= 1.5mm or less
RFMT= COR, SAG, 3D, MIP, VR
- Purpose of CTA RUNOFF?
- What are the area(s) of bifurcation important in CTA RUNOFF?
- Locations? - Major acquisition concern for CTA Runoff?
- Image Abdominal Aorta & Peripheral Arteries through feet during arterial phase
- Abdominal Aorta bifurcates into R&L Iliac Arteries @ L4
- R&L Iliac Arteries each bifurcate into internal & external iliac arteries @ L5-S1 joint - Exam will be scanned / completed before contrast reaches patients feet
- What is the rate of CTA Runoff?
- Why? - What type of slices for CTA RUNOFF?
- Why? - The Abdominal Aprta bifurcates where & into what?
- Start @ 4.0 but go lower to increase arterial phase imaging
- Thin
- Greatest details possible - R&L Common Iliac Arteries @ L4
- Positional Goal for CT Upper Extremity?
- Ideal Position if Tolerable? - Name of Ideal position?
- What is best imaged? - If patient can’t tolerate above position, What can be done?
- Why isn’t this ideal?
- Area of interest positioned away from rest of body
- “Superman” Position. = Patient Prone, Arm of Interest Raised over head & hand supinated - Superman
- Hand, Wrist, Forearm, Elbow without Head being imaged - Supine with arm neutral at side
- Streak artifact may occur from pt body
- for CT Upper Extremity, What is positioning for Shoulder, Clavicle &/or Humerus?
- Slices for CT Upper Extremity?
- Why? - Scanning axis of CT Upper Extremity?
- Why?
- Patient supine with arm at side w/ arm not of interest raised over head
- Thin
- Image best details - Perpendicular long axis of ROI
- Ensure entire ROI scanned & best detail
- How should CT Upper Extremity Reconstruction be done?
- Why? - If CT Upper Extremity use IV contrast, where is IV & What’s rate?
- Which phase scanned?
- 50% overlap
- Maximize quality of 3D Recons - 3ml/s - Portal Venous Phase
- IV in arm not of interest
CT UPPER EXTREMITY
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Lower Arm = Superman (Prone, ROI Arm Raised over head & hand supinated)
Upper Arm = Supine, Arm Neutral at side & non ROI arm raised. ** Most important is ROI away from body**
PREP= NONCON, but if 3.0ml/s @ 80-120ml
CLIN= Trauma, Cellulitis, Neoplasms, Arthritis, Multiple Myeloma, Infection, Abcess
SCAN= Entire ROI from joint above to joint below
ALG.= Soft Tissue & Bone Window
SLICE= Thin, Less than 2mm
RFMT= COR, SAG, 3D
- CT Lower Extremity general positioning?
- Why? - For Pelvis, Hip, Femur & Tib Fib, what positioning is important?
- What about knee positioning?
- Why is it different?
- Non area interest away as much possible.
- Minimize scatter in ROI - Leg straight as possible w/ unaffected side bent or out of way
- Knee bent varying degrees of flexion
- Better visualization of patella
- In regard to CT Lower Extremity of Foot, What are the regions of the foot?
- What do they each consist of - Positioning considerations for CT of Foot?
- Four imaging planes for CT Foot:
- How is each scanned
- Forefoot (Phalanges & metatarsals)
- Midfoot (Navicular, Cuneforms & Cuboid)
- Hindfoot (Talus & Calcaneus) - Midfoot = Foot interest flat on table
- Hindfoot or ankle = flat/toes up - Direct Axial = Toes pointing up
- Oblique Axial = Parallel to metatarsals
- Sagital = Medial to Lateral
- Coronal = Post to Ant
- Slices for CT Lower Extremity?
- Why? - Scan direction of CT Lower?
- Why? - How are Recons for above done?
- Why?
- Thin
- Best Detail - Perp long axis
- Ensure entire ROI & best detail - At least 50% overlap
- Most accurate
CT LOWER EXTREMITY
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine, ** Most important is ROI away from body**
PREP= NONCON, but if 3.0ml/s @ 80-120ml
CLIN= Trauma, Cellulitis, Neoplasms, Arthritis, Multiple Myeloma, Infection, Abcess
SCAN= Entire ROI from joint above to joint below
ALG.= Soft Tissue & Bone Window
SLICE= Thin, Less than 2mm
RFMT= COR, SAG, 3D
CT ARTHOGTAM
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= Supine
PREP= Iodinated Contrast direct into Joint, May also inject room air
CLIN= Degenerative Disease, Athletic Induced Trauma
SCAN= Entire Joint of Interest
ALG.= Soft Tissue & Bone Window
SLICE= Thin, Less than 2 mm
RFMT= COR, SAG, 3D
- What is CT Arthogtam?
- How is it performed?
- What is this injection called?
- Contrast injected into joint space & then imaged
- Contrast diluted with Saline before injected into joint space
- Room air may also be injected - Intra Articular Inejctopn
CT MYELOGRAM
Patient:
Prep:
Clinical Ind: (w & w/o)
Scan Range:
Algorithm:
Slice Thickness:
Reformats:
PT= SUPINE
PREP= CON via Intraethically
CLIN= Degenerative Disease, Post Op
SCAN= Entire ROI
ALG.= Soft Tissue & Bone Window
SLICE= Less than 2mm
RFMT= COR, SAG
- What part of the spine can be performed in a CT Myelography?
- Where is contrast injected?
- Name for this? - What is CT Fluoroscopy typically used for?
1 Can be C, T &/or L Spine
- Injected into subarachnoid space surrounding spinal cord
- intraethecal injection - Needle Guided procedures
- Intraethical vs Intrarticular injection?
- How to reduce exposure during CT Fluroscopy?
- Typical CT IR cases?
- Intraethical = mylogram, subarachnoid space
- Intrarticular = Arthogram, intra articular joint space - Shields Staff, Shield non ROI, Limit technical parameters to reduce dose
- Biopsy, Drain Placement, RF Ablation, Aspiration
- What determines patient positioning in CT IR cases?
- Why is a small ROI important in CT IR?
- CT PET stands for:
- What procedure, Anatomical ROI, Patient Condition
- Due to high exposure, small ROI limits dose and exposure
- CT Positron Emission Tomography
- CT PET utilizes what?
- What does it show? - Where are these typically done?
- What’s typical dose for CT PET?
- Uses Fludeoxyglucose F18 Radiopharmacuetical
- To measure amount of FDG uptake by body’s cells - Nuclear Medicine
- FDG is 10-15 cm
- In CT PET, Malignant cells will have what type uptake?
- Typical PET exams?
- How can CT aide in Radiation Therapy?
- increased
- Head Neck Lungs Breast & GI
- Determine beam arrangement to be used during