Bone Scan Procedures

alkathryn's version from 2016-06-18 04:45


Question Answer
Sensitive but notspecific
Sensitive formets and other pathologies
Bone scans are more sensitive than xray
Most mets seen in axial areas
metastatic disease from breast, prostate, lung, and kidney
Main three indicationsstaging and eval of malignancies, osteomyelitis, page's disease
Cancer requiresnon-three phase, whole body
In osteomyelitis, ____ will be hotAll three
3-phase flowbolus in with 2-4 sec/frame, dynamic
In cellulitis, ____ will be coldBone
Best possible bone imaging agent currentlyF-18 Sodium Fluoride, PET
Previous pharmaceuticals for bone imagingCold PYP
Main bone agent todayTc-99m diphosphonate agents
MDP AKAMethylene disphosphonate
HDP AKAHydroxymethylene diphosphonate
MOLheterionic exchange, chemisorption, hypdroxyapatite crystal matrix
______ increases blood supply to 'hot spots'Osteoblastic activity
Advantages of Tc-99m dipiho. agentsGreater stability in-vivo, larger dose and less radiation, low cost, scan in 2-4 hours
SNMMI scan time2-4 hours
SNMMI dose20-30 mCi
Typical dose20 mCi
Patient prepID, verify, explain
Once injected,return 2-4 hours, hydrate well, void frequently, empty bladder, no metal objects
When does agent reach equilibrium10 minutes of injection
Non-targetbackground (tissue)
Three phases:Flow, Blood Pool, Bone Statics
Inject ____ of injured body partOpposite
Infiltration can causeuptake in lymph nodes
Do not inject where?On the arm where lymph nodes have been removed.
___% of rphx gets excreted through urine50
Best images occur at12 hours
Collimator for bone scanLEHR or LEAP
Possible procedures3-Phase, WB vs Limited, SPECT
3-phased performed forRSD, avascular necrosis, osteomyelitis, or fracture
A positive 3-phase =Increase blood flow
Poolstatic eval of rphx in soft tissue
Pool time500 kcts/image before 10 mins
Pool delays2-4 hours, static
WB time10-15 cm/min
Statics of WB500-1000 kcts
SPECT may be requested wheresubtle changes are seen or when detection by static is difficult
SPECT is very beneficial forribs, spine, pelvis
Normal bone studies showsymmetric uniform uptake, bladder & kidney uptake, sternoclavicular joints, acromiclavicular joints, end of long bones, sacroiliac joints, vertebae
Normal variantsepiphysial plates in children, breast blushing in young women
Attenuating artifactsmetal, jewelry, belts, ect
Pelvis lesions may obscured bybladder --- important to empty
Other artifactsurine catheters, IV infiltration, contaminated clothing, patient movement, imaging too soon or lack of hydration, degenerative joint disease/surgery/trauma
Old trauma can causefalse positive
Radiation therapy maydecrease uptake (decrease cells in the bone)
Abnormal studiesasymmetric, focal areas of increased uptake, "super scan"
Super scanbone uptake showing brightly, no kidney bladder distal extremities facial bones or soft tissue uptake
super scan caused bywidespread metastatic disease
Fractures are among themost common pathologic conditions of bone
Fractures heal byadding bone to repair the site of trauma
Fractures will show as"hot" or increased uptake
Fracture imaging done usually afterxray shows up negative

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