title: Effect of needle gauge and lobe laterality on parenchymal liver biopsy outcome: a retrospective analysis.
abstract: OBJECTIVE
  To analyze the effect of lobe selection, needle gauge, and number of passes on procedure outcomes in terms of specimen length and post-procedure complications.
  
  
  METHODS
  In this HIPAA-compliant, IRB-approved retrospective study, the data from 771 ultrasound-guided adult parenchymal liver biopsies were analyzed. Post-procedure complications were assigned a 3-point rating scale. Associations between specimen length and post-procedure complications with lobe laterality, needle gauge, and number of passes were analyzed. Multivariate logistic regression models were used to analyze the likelihood for achieving a specimen length of at least 2 cm.
  
  
  RESULTS
  Post-procedure complications were not associated with lobe laterality, needle gauge, and number of passes (p > 0.3). Specimen length was associated with the number of passes dichotomized at the study mean (p = 0.007), but not with lobe laterality or needle gauge (p > 0.2). After adjusting for lobe laterality and needle gauge, procedures with 1 or 2 passes were associated with a higher likelihood of obtaining a 2 cm or longer specimen (OR 2.469; CI 1.08-5.63, p = 0.0315) than procedures with 3 or more passes, possibly due to poorer sample quality. After adjusting for lobe laterality, an 18-gauge needle was associated with higher odds of a biopsy procedure with 1 or 2 passes (OR 3.665; CI 1.93-6.95, p < 0.0001) than a 20-gauge needle.
  
  
  CONCLUSIONS
  Lobe laterality was not associated with specimen length or post-procedure complications. An 18-gauge needle compared to a 20-gauge needle could reduce the need for a procedure with more than 2 passes. There was no difference in post-procedure complications between the two needle sizes.
authors.affiliation: Department of Radiology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA, 01655, USA, gopal.vijayaraghavan@umassmemorial.org.
authors.forename: Gopal R
authors.initials: GR
authors.lastname: Vijayaraghavan
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Vedantham
authors.forename: Vikram
authors.initials: V
authors.lastname: Rangan
authors.forename: Adib
authors.initials: A
authors.lastname: Karam
authors.forename: Larry
authors.initials: L
authors.lastname: Zheng
authors.forename: Abhijit
authors.initials: A
authors.lastname: Roychowdhury
authors.forename: Sarwat
authors.initials: S
authors.lastname: Hussain
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D006801:Humans; D061705:Image-Guided Biopsy; D008099:Liver / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009339:Needles; D018579:Patient Selection; D012189:Retrospective Studies; D018084:Ultrasonography, Interventional; D055815:Young Adult