Richard Gary Barr MD, PhD, Presenter: Consultant, Siemens AG Consultant, Koninklijke Philips Electronics NV Research grant, Siemens AG

Joseph Rafael Grajo BS, Abstract Co-Author: Nothing to Disclose

We previously reported that cysts have a specific appearance on Elasticity Imaging (EI). We described this appearance to resemble a "bull's-eye" with a black lesion featuring a bright spot in the center and a bright posterior spot on the elastogram.  This appearance has since been determined to be an artifiact of EI.  The purpose of this study is to evaluate the sensitivity and specificity of this artifact for cysts.

A retrospective review of 383 patients having an EI for diagnostic breast ultrasound evaluation was reviewed.  There were 127 lesions that had the characteristic "bull's-eye" appearance of cysts on the elastogram.  The pathology reports of those lesions biopsied were reviewed.  The corresponding B-mode images of these lesions were reviewed to determine the number that had characteristics of a benign cyst, complicated cyst or solid lesion.  Lesions which had a solid component in the "cyst" in the EI were excluded from analysis.

The 127 lesions with the "bull's-eye" appearance varied in size from 2mm to 40mm (mean 9mm).  Of these lesions, 62 (49%) were biopsied and pathologically confirmed as simple or benign complicated cysts.  65 (51%) of the lesions were simple cysts on B-mode and were not biopsied.  59 (91%) cases had a B-mode appearance of a complicated cyst and 6 (9%) had an appearance of a solid lesion.  All of the complicated cysts and solid appearing lesions were biopsied.  The "bull's-eye" artifact had a sensitivity of 100% and a 100% positive predictive value of a benign cyst based on the biopsy results of the complicated cysts and solid lesions.  All simple cysts and complicated cysts on B-mode had the "bull's-eye" appearance on EI.  Based on the B-mode characteristics of a simple cyst or complicated cyst, the "bull's-eye" sign had a 100% specificity.  The true specificity cannot be calculated based on this study, as all solid lesions were not biopsied to determine if they were cysts or solid. 

The "bull's-eye" appearance of cysts on EI is an artifact and has a very high sensitivity and positive predictive value for determining that a lesion is a benign cyst.

Complicated cysts and cysts which appear solid lead to a large number of benign breast biopsies.  This sign may eliminate the need for a large number of these biopsies. 

Barr, R, Grajo, J, Sensitivity and Specificity of the "Bull's-eye" Artifact on Breast Elasticity Imaging to Characterize Cysts.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6014225.html