title: How often does ultrasound marking change the liver biopsy site?
abstract: OBJECTIVE
  The aim of this study was to answer the question: How often does ultrasound change the liver biopsy position, when a percussion technique is applied, because of intervening structures? A secondary objective is to compare the performance of the hepatologist to a radiology technician to demonstrate safety of a self-training technique.
  
  
  METHODS
  One hundred sixty-five consecutive outpatient liver biopsies were studied. Using a standard percussion technique, a biopsy site was chosen and marked. Ultrasound was applied to the marked site. An adequate site was determined to be one without intervening structure within 6 cm of liver depth. If an intervening structure was found, an alternative site was chosen by ultrasound. Data recorded included reason for change of position, distance of moved site from original site, and complications. The first third of liver biopsies were done with assistance of a certified radiology technician performing ultrasound, the last two-thirds were done by the hepatologist after observing the first 64 biopsies.
  
  
  RESULTS
  Ultrasound changed the position in 21 of 165 patients. The ultrasound caused an abortion of the procedure in 4 of 165 patients. Ultrasound changed management in 15.1% of patients. Reasons for change were lung (10 patients), gallbladder (6), large central vessel (4), >4-cm rim of ascites (2), colonic loop (1), slim liver edge (1), and focal liver lesions (1 patient). There was a 1.8% multiple pass rate. No serious complications occurred.
  
  
  CONCLUSIONS
  Ultrasound changed management 15.1% of patients. A hepatologist could perform ultrasound marking after a period of observation, without compromising results. A low multiple pass rate was observed when applying ultrasound and percussion. Avoided structures could explain decrease in pain when ultrasound is applied.
authors.affiliation: The Milton S. Hershey Medical Center, The Pennsylvania State University, Department of Medicine, Hershey 17033-0850, USA.
authors.forename: T R
authors.initials: TR
authors.lastname: Riley
mesh_terms: D000553:Ambulatory Care; D001201:Ascites / Q000000981:diagnostic imaging; D001706:Biopsy / Q000379:methods*; D003106:Colon / Q000000981:diagnostic imaging; D005260:Female; D005704:Gallbladder / Q000000981:diagnostic imaging; D005762:Gastroenterology / Q000193:education; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology*; D008107:Liver Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D010474:Percussion; D011446:Prospective Studies; D012449:Safety; D013679:Technology, Radiologic / Q000193:education; D018084:Ultrasonography, Interventional