Cytopathology
Palpation guided fine needle aspiration
Fine needle biopsy technique

Author: Joe D. Jakowski, M.D. (see Authors page)

Revised: 6 February 2018, last major update August 2013

Copyright: (c) 2002-2018, PathologyOutlines.com, Inc.

PubMed Search: Fine needle biopsy [title] technique

Cite this page: Jakowski, J. D. Fine needle biopsy technique. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/cytopathologypgfnatechnique.html. Accessed June 19th, 2018.
Definition / general
  • Personal preference and teaching exposure will probably influence the FNA technique of choice; however, it is advantageous to be familiar and proficient in both techniques
  • The most important part of the performance of any fine needle biopsy regardless of the particular technique is:
    • The needle gets into the target (and preferable stays within it throughout the biopsy)
    • Performing the CUTTING action with the needle tip (back and forth excursions within the target) which is key to obtaining an adequate sample
  • Other very key elements of the FNA technique include:
    • Use of long amplitude excursion
    • Performing 2 - 3 excursions per second
    • Changing the needle path during the excursions to "fan out" in a cone shaped sampling area
      • Important: redirect the needle only when at the top of the cone / when the needle is almost withdrawn from the target
      • Attempting to redirect the needle when it is at the base of the cone / deep within the target is difficult and may lacerate the tissue
    • Limit the time of the biopsy to less than 5 - 10 seconds
Fine needle biopsy techniques
  1. Fine needle aspiration biopsy (also known as traditional FNA, suction or aspiration biopsy):
    • Needle biopsy using suction (negative pressure) by attached syringe
      • Syringe may be directly attached to needle OR
      • IV tubing may be placed between needle and syringe
    • Steady suction during the needle excursion is recommended (DO NOT pump the syringe)
  2. Capillary action needle biopsy (also known as the French, Zajdela, needle only or non aspiration technique):
Comparison of the capillary (non aspiration technique) to traditional (suction) FNA
  • The literature is conflicted regarding the superiority of one technique over the other; they may be used consecutively during a single procedure if needed

  • Capillary (non aspiration technique)
    • Reduces trauma to cells and tissues
    • Less hemorrhage / bloody specimens and higher concentration of cells in the specimen
    • Less "scary" to the patient as this small needle only technique may be concealed within your biopsy hand
    • Increased fine motor coordination of the needle tip and thus increased sampling precision (using fingers to control sampling)
      • May be more useful for very small targets
    • Better tactile sense to "feel" the consistency of the target (fingers are closer to the needle)
    • May yield fewer cells but provides sufficient material for diagnosis
    • However, cannot drain cystic lesions or perform therapeutic decompression of a target if needed

  • Traditional (suction) FNA
    • May provide larger yield of cells
    • Less fine motor coordination of the needle tip (uses wrist, arm and shoulders to control sampling)
    • Less tactile sense to "feel" the consistency of the target (fingers are farther away from the needle)
    • Equipment may be more alarming to the patient because of the addition of the large syringe and syringe holder
    • Can be used to drain cystic lesions or perform therapeutic decompression of a target if needed (Acta Cytol 1989;33:809, Acta Cytol 2002;46:30, Acta Cytol 1998;42:679)
Amount of specimen collected from an FNA
  • Mean sample weight of material obtained from FNA increases with experience of aspirator (4.6 mg in the least experienced [50 - 100 biopsies performed] to 17 mg in experienced practitioners [> 200 biopsies performed]
  • Variables that influence amount of specimen collected include:
    • Suction (force, duration and rate of increase)
    • Needle movement (number, frequency and amplitude of passes, angle between the passes, acceleration of movement)
    • Needle (size, content, tip configuration)
    • Type of target tissue (Br J Surg 1989;76:1270)