LO4 - Biopsy Technique Flashcards
What is/are the most common US guided biopsy for soft tissue?
FNA biopsy
Core biopsy
FNA uses what gauge needle
20-25 gauge
Technique rad uses to collect cells into cannula during FNA
Back and forth motion
When is FNA indicated (3)
Nodules/masses
Enlarged LN
Inflamed tissue
What are common sites for FNA (3)
Breast
Thyroid
LN in neck, groin, axilla
What is cytopathology/cytology
Diagnoses malignant/premalignant cells and diseases on microscopic level
Gauge level for core biopsy
14-19 gauge needle
Between FNA and core biopsy, which collects a larger sample?
Core
When is a core biopsy indicated
Abnormal imaging (CT, US, mammogram) Abnormal biochemistry (proteinuria, elevated LFTs/enlarged liver)
Obtains abnormal soft tissue sample / sample in organ
what is the most common core biopsy needle mechanism
Re-usable (ProMag) - punch
Disposable (super core/Trucut) - controlled click
What happens to samples after collected from core biopsy
Tissues are preserved in formaldehyde then sent to SURGICAL PATHOLOGY/HISTOLOGY
Biopsy techniques (2)
Free hand
Needle guided
At what angle is the needle inserted when sampling superficial structures versus deeper structures. Describe the orientation relative to the transducer
Superficial = shallow angle, needle hub away from the transducer Deep = steep angle, needle hub close to transducer
Describe some pros to the free-hand technique
Easy skill to replicate once mastered
Costs less, does not need needle guide
Most institutions have needles & syringes Less administrative work to order right needle
Can easily avoid nearby structure/can reach hard to biopsy area because angle is not controlled by guide
What are some cons to the free-hand technique
User-dependent
Potential tissue damage
Needle angle not controlled
Big learning curve
What are some pros for needle guided technique?
Controlled needle insert angle, needle tracks closer to each other
Less tissue damage
Less learning curve
Decreased procedure time
what are some cons to guided biopsy technique?
Expensive
Specific guides for specific machines/transducers - pt scheduling
Difficult to manipulate guide near rib spaces or lesions closer to diaphragm due to set angles
Liver biopsy contraindications
Uncooperative pt Extrahepatic biliary obstruction Bacterial cholangitis Abnormal coagulation indices As cites Cystic lesions Amyloidosis Pt body habitus/poor penetration of sound through soft tissue
Coagulopathy suggested threshold INR liver biopsy
<1.4-1.5
PTT suggested threshold liver biopsy
<45-50 s
PLT suggested threshold liver biopsy
> 50 000 - 70 000
What is used to correct clotting abnormalities (2)
Vitamin k or FFP (fresh frozen plasma)
Pre liver biopsy (6)
Requisition: history & bloodwork Visibility Access Ascites Smaller intrahepatic vessels Target: peripherally located lesions with normal parenchyma
Liver biopsy patient position
Supine / left lateral deuce
how many samples are obtained for liver biopsy
2-6
In what time frame will most complications occur after liver biopsy
First 3 hrs
Liver biopsy complications (8)
Abdo/shoulder pain Hematoma Hemobilia Hemo- or pneumothorax Vasovagal rx Puncture to adj organs Peritonitis Mortality
Where is the selected choice for a renal biopsy
Renal parenchyma in lower pole left kidney
Renal biopsy contraindications
Bleeding diathesis Severe hypertension Seeding RCC Hydronephrosis Infection Pt unable to lie prone Obesity
renal biopsy complications
Pain Hematuria Bleeding/hematoma Tract seeding Infection Mortality
When do most complications occur after a renal biopsy
80-100% <12 hours
40-50% <4 hrs
BP after renal biopsy should be taken when and what should the diastolic reading be under?
Within 24 hours
<90 mmHg
For LN biopsy, where are FNA samples sent and where are core samples sent?
FNA=cytology
Core=histology
what are symptoms enough to indicate a LN biopsy? (3)
Ongoing fever, night sweats weight loss
LN biopsy diagnosis normal result (3)
Normal # LN
Structure/appearance LN normal
No signs of infection
Abnormal LN biopsy result (4)
Sign of infection (mono/TB)
Cancer cells present
HIV
Inflammatory disease (sarcoidosis)
Contraindications to LN biopsy (3)
Uncooperative pt
Allergies
Blood thinners
Complications LN biopsy (6)
Pain Bruising Bleeding Infection Allergic rx Lymphedema
