35. Image-guided biopsies. Cyst puncture, drainage (biliary, renal, bladder etc.)

From greek.doctor
  • Needle size
    • Measured in gauges (G)
    • More gauges -> thinner needle
    • 20G is thinner than 18G
  • Image-guided biopsies
    • Fine needle aspiration biopsy
      • Tissue loses organization
      • 20 – 22G needle
      • Indications
        • Breast biopsy
        • Thyroid biopsy
        • Lymph node biopsy
    • Core biopsy = trucut biopsy
      • Tissue maintains organization
      • Ultrasound or CT guided
      • Trucut needle is used
        • 18G needle
        • Bigger than FNAB needle
  • Drainage and puncture
    • Drainage = Long-term tube placement/emptying of fluid
    • Puncture = one-time sample acquisition
    • Can be guided by US or CT
    • Indications
      • Abscess
      • Exudate
      • Transudate
      • Haematoma
    • Can be
      • Diagnostic (determine composition of pleural effusion)
      • Therapeutic (abscess)
    • Percutaneous transhepatic cholangiography (PTC)
      • To visualize anatomy of biliary tract
    • Percutaneous transhepatic biliary drainage (PTBD)
      • To relieve pressure in bile ducts due to blockage
      • Ultrasound-guided