Radiology Block 1 Flashcards
What is the sequence from highest to lowest wavelength/strength for ionizing radiation?
Gamma: Shorter, higher freq/energy Xray UV Visible Infrared Microwave Radio: longer, lower freq/energy
Define Scintigraphy
Radioactive tracer used for imaging organ function
What is the use for radionuclide Tc-99m?
Numerous
Most frequently for bone scans
What is the use for radionuclide Ga-67?
Inflammation
Infection
What is the use for radionuclide In-111?
Infection
Tumors
What is the use for radionuclide Ti-201?
Cardiac Perfusion
What are 7 variations of nuclear medicine imaging?
Bone scan Myocardial perfusion HIDA V/Q Thyroid scan PET SPECT
Define Sclerotic
Unhealthy hardeing/thickening of bone
Define Lytic
Destruction of area of bone by disease/cancerous cells
Define Osteomalacia
Bone softening due to insufficient mineralization
What are the Generalized reasons for Inc/Dec bone density?
Inc- Diffuse osteoblastic metastases, osteopetrosis
Dec- Osteoperosis, Hyperparathyroidism, Rickets/osteomalacia
What are the Focal reasons for Inc/Dec bone density?
Inc- Localized osteoblastic metastases, Avascular necrosis, Paget Disease
Dec- Localized Osteolytic metastases, Multiple Myeloma, Osteomyelitis
What are 3 pitfalls to recognizing Fx?
Sesamoids
Accessory ossicles
Unhealed Fx
What are the two types of Comminuted Fx?
Butterfly
Segmental
What are 5 types of healing fractures?
Periosteal reaction Delayed union Nonunion Malunion Pseudoarthrosis
What are the 3 classifications of arthritis?
Hypertrophic
Erosive
Infectious
What are the types of Hypertrophic arthritis?
Primary Secondary Erosive Charcot Ca Pyrophosphate Deposition Disease
How how many Hounsfield units have air, bone, fat, water and soft tissue been assigned?
Air: -1000 HU Bone: 400-600 HU Fat: -40 - -100 Water: 0 Soft tissue: 20 - 100
Radiation causes biological effects at a cellular level in what two ways?
Direct damage
Indirectly forming radicals
What are 4 examples of testing done by CT that are beneficial for provider and PT?
Virtual colon/bronchoscopy Fx Coronary angiography Abdominal pathology Trauma Cardiac calcium
What is a preferred imaging form for women of childbearing age and during pregnancy?
US
What is the imaging study of choice for imaging female pelvis and pediatric PTs?
US
What form of imaging can differentiate cystic verse solid lesions in PTs of all ages?
US
US is the image of choice for what types of PT populations?
Female pelvis Pediatrics Cystic vs solid lesions Non-invasive vasculature Fetal/placental Real-time fluid aspiration and biopsy
What are 4 common evaluation images US is used for?
Cystic vs solid breast masses
Thyroid nodules
Tendons
Newborn spine/brain/hips
What type of imaging are MRIs widely used for?
Neurological
Soft tissue
Masses
Female pelvis
What are 3 uses of interventional radiology?
Iodine contrast used to view anatomy, pathology or position of implants
How are radioisotopes artificially produced?
Neuron enrichment in nuclear reactor or cyclotron
What are two examples of naturally occurring radioisotopes?
Uranium
Thorium
Define SPECT
Single-photon Emission Computed Tomography
Gamma camera rotates around PT capturing 2D images from numerous angles and formed into 3D images by computer
What type of nuclear injection is used during PET scans?
Positron (positive electron) isotope attached to pharmaceutical
When is PET scanning most often used?
Diagnosis and treatment f/u of cancer
Locate hidden metastases
Detect recurrence
Define Flat Plate
Plain film of abdomen w/ PT lying supine
What is the systematic approach to reading abdominal scans?
1- gas pattern
2- etraluminal air
3- abnormal abdominal calcifications
4- soft tissue masses
What is the difference between distended and dilation when reading abdominal CT scans?
Distended- bowel filled w/ normal amounts of air, normal
Dilated- bowel filled with beyond normal amounts of air, abnormal
Why would an increase number of air-fluid levels be seen in a PTs colon?
Recent enema
Anti-cholinergic meds
Anti-peristaltic meds
What is being looked for with a supine abdomen view?
Bowel gas patterns
Masses
Calcifications
What is being looked for with a prone abdomen view?
Gas in retrosigmoid colon
What is being looked for with a upright abdomen view?
Air/fluid levels in bowel
What is being looked for with a upright chest view?
Air/effusions
Pneumonia
Supine view is AKA ?
Scout film
Define Organomegaly
Evaluation of soft tissue structures in abdomen
Define Riedel lobe
Right lobe of liver extending to iliac crest in women
Define FAST
Focused Abdominal Sonogram for Trauma
Portable US for unstable PTs to look for free peritoneal fluid
What is a FAST exam used in place of?
Peritoneal lavage
What are the most commonly injured solid organs from blunt trauma?
Spleen
Liver
Kidney
Bladder
What is the most frequently injured organ from blunt and penetrating trauma?
What is the preferred imaging technique to locate it?
Right lobe of liver
CT w/ contrast
Spleens are usually injured from what mechanism of injury?
What is the imagine method of choice to screen?
Deceleration of unrestrained passengers
CT due to the fact the spleen is the most highly vascular organ
What are the most common causes of kidney injuries?
What is the imaging method of choice?
Motor vehicle accidents
CT w/ contrast
What causes shock bowel injuries?
Blunt abdominal trauma w/ hypovolemia or hypotension
What is the MOA for bladder injuries?
What is the preferred imaging method to detect it?
Pelvic Fx
CT cystogram
What is the MOA of urethral injuries?
What is the imaging method of choice?
Pelvic/blunt trauma in males
Retrograde Urethrography RUG
What is the difference between luminal and mural?
Luminal- arise from mucosa, polyp/carcinoma
Mural- arise from wall, leiomyomas/lipoma
Loops of the GI system have to be in what position for accurate/effective examination?
Fully distended
What is the study of choice for diagnosing aspiration?
Esophagography
Lumen of the stomach is studied through what form of imaging?
Wall thickness and structures outside of the stomach are examined by?
Endoscopy
CT w/ contrast
What do the different colors on US mean?
Echogenic- bright/white
Sonolucent- dark/black
What is the direction orientation of images produced by US?
Sagital/longitudinal
Transverse
What effect is used by US to determine if fluids are heading towards or away from the transducer?
Doppler effect
US is the study of first choice for what abnormailities?
Biliary system
How can gallstones and biliary sludge be differentiated on an US?
Sludge doesn’t produce acoustical shadowing
PT undergoing HIDA exams will show what images if cystic duct is obstructed or if the common bile duct is obstructed?
Cystic- tracer won’t appear in gallbladder
Common bile- tracer won’t appear in small intestine
What is the screening study of choice for asymptomatic, pulsatile abdominal masses?
US
What is the imaging study of choice for evaluating pelvic masses and pelvic pain in female PTs?
US
What is the imaging study of choice for evaluating uterine fibroids?
US- transabdominal or transvaginal
When/why are MRIs used to evaluate uterine fibroids?
Complicated surgical case planning
What is the imaging study of choice for evaluating ovaries?
US
What form of imaging is used to identify the best location to perform a paracentesis to remove ascitic fluid?
US
What form of imaging is the best at identifying the presence of an intrauterine pregnancy?
US
Define Duplex Sonography
Vascular US with Doppler spectral waveform
What is the highest yielding sonographic exam for DVTs examination?
US of symptomatic PT w/ symptoms above the knee
MRI imaging is better than CT scans for what two purposes?
Soft tissue abnormalities
Changes in tissue over time
What form of imaging is preferred to study bone marrow components?
MRI
What is the prototype for generalized increase in bone density?
Carcinoma of prostate
Sclerotic lesions that affect the cortex usually cause what abnormality?
Sclerotic lesions that affect the medullary cause what abnormality?
Cortex- periosteal new bone formation
Medulla- punctate, amorphous lesions
What is the imaging method of choice for studying skeletal metastases?
Radionuclide bone scan
What is the imaging method of choice for detecting avascular necrosis?
MRI
How is Paget’s Disease diagnosed?
Conventional radiograph
What are the imaging hallmarks of Paget’s Disease?
Thickened cortex
Accentuation of trabecular pattern
Increased bone size
What is the imaging method of choice for bone mass density tests?
Dual energy x-ray absorptiometry DEXA
What is the most common primary malignancy of bone in adults?
Multiple myeloma
The most common cause of osteomyelitis is what microbe?
Staph Aureus
What is the difference between a simple and comminuted fracture?
SImple- two fragments
More than 2= comminuted
What is the most common form of arthritis and where does it show?
Primary OA
Hips, knees, hands
What is the imaging hallmark of Primary Osteoarthritis?
Marginal osteophyte formation, subchondral sclerosis, subchondral cysts, narrowing of the joint space
What bone abnormality is seen on all forms of arthritis?
Narrowing of joint space
Where is erosive osteoarthritis most common?
Proximal and distal interphalangeal joints
What is the most common cause of Charcot arthropathy and where is it seen?
Diabetes
Feet and ankles
Charcot arthropathy can mimic what other bone disorder?
Osteomyelitis
Where is CPPD commonly found in the body?
Wrists cartilage
Menisci of knee
Hook shaped formations at metacarpal heads
What are the 4 types of erosive arthritis?
RA
Gout
Psoriatic arthritis
Ankylosing spondylitis
What is the imaging hallmark for RA?
Metacarpal radial deviation
Phalangeal ulnal deviation
What type of arthritis has atlantoaxial subluxation
RA
Proximal joints
Gout is a formation of what type of crystal?
Calcium urate
Define Tophi
Skin manifestation from gout
PT presents w/ olecranon bursitis, what is first diagnosis?
Gout
What form of arthritis presents with “pencil-cup” deformity
Psoriatic arthritis