Ch 4 TIRADS + Biopsies Flashcards
What does TIRADS stand for?
Thyroid imaging reporting + data system
What is TIRADS?
-A 5 point classification system that uses u/s characteristics to determine the risk + suspicion for malignancy in thyroid nodules
-Developed TIRADS to help reduce the amount of biopsies being done
List the 5 TIRAD classifications?
TR 1: benign (no FNA, 0 points)
TR 2: not suspicious (no FNA, 2 points)
TR 3: mildly suspicious
(FNA if >2.5cm, follow up if >1.5cm, 3 points)
TR 4: moderately suspicious
(FNA if >1.5cm, follow up if >1cm, 4-6 points)
TR 5: highly suspicious - some exceptions here
(FNA if >1cm, follow up if >0.5cm, >7 points)
When would we not use TIRADS?
When a lesion is under 5mm or 0.5cm
What size must a lesion be to have a biopsy done?
> 1cm
What are the 4 composition options?
-Cystic or almost completely cystic (0 points)
-Spongiform (0)
-Mixed cystic + solid (1)
-Solid or almost completely solid (2)
If composition can’t be determined, which option do we choose?
Solid
What is spongiform composition?
When at least 50% of the nodule is comprised of tiny cysts
(if there are other features present like peripheral or macro calcs, do NOT classify as spongiform)
What are the 4 echogenicity options?
-Anechoic (0 points)
-Hyperechoic/isoechoic (1)
-Hypoechoic (2)
-Very hypoechoic (3)
(all echogenicity is compared to thyroid, except very hypoechoic is compared to surrounding neck muscles)
If the echogenicity can’t be determined, which option do we choose?
Isoechoic
What are the 2 shape options?
-Wider than tall (0 points)
-Taller than wide (3 points)
(measured in TRV)
What are the 4 margin options?
-smooth (0 points)
-ill defined (0)
-lobulated or irregular (2)
-extra thyroidal extension (3)
If the margin can’t be determined, which option do we choose?
ill-defined
What are the 4 echogenic foci options?
-None or large comet tail artifact (0 points)
-Macrocalcifications, large enough to produce shadowing (1)
-Peripheral rim calcifications (2)
-Punctate echogenic foci (3)
What defines a large comet tail?
When the tail is >1mm + is V shaped
(this is a non-suspicious finding)
Peripheral rim calcifications can be dense enough to obscure the internal components of the nodule, how would we describe the composition + echogenicity of it now?
Composition: solid
Echogenicity: isoechoic
Do punctate echogenic foci have comet tails?
Foci <1mm sometimes can have a small comet tail
Mixed cystic + solid lesions should be characterized by what?
The soft tissue component
No further characterization is required for what type of nodule?
A spongiform nodule that is identified as TR 1
What is a fine needle aspiration (FNA)?
-Cytological evaluation used to test for malignancy, confirm benignity or determine the nature of other lesions
-Considered minimally invasive
-Is an outpatient procedure
-Uses a smaller needle than a core biopsy
What are complications with FNA?
-Risk of bleeding or infection (m/c)
-Voice hoarseness
-Seeding/spreading of cancer (rare)
Does FNA or a core biopsy use a smaller needle?
FNA
What is a core needle biopsy?
-Biopsy gun with a hollow core needle
-Obtains a larger amount of tissue
-Uses a larger needle than FNA
-Associated with more complications than FNA
(less repeat biopsies are needed b/c they are taking a greater sample, but this increases risk of complications)
Explain how an u/s guided FNA procedure works?
-Sterile technique, local anesthetic + 25g needle used
-Same pt set up as for a thyroid u/s
-U/s guides the needle into the lesion of interest
-Multiple samples obtained from the lesion, placed into cytology fluid + sent to lab for testing
What are limitations of an FNA?
-Inconclusive results or repeat biopsies needed (2/10)
-Lacks specificity for certain cancers (follicular carcinoma, hurthle cell carcinoma + lymphomas)
How can we reduce the repeat rate of FNA’s?
-Can use u/s guidance
-By having an onsite tech to check the cells right away once they are drawn to ensure they will work for testing
