title: Breast ultrasound tomography versus MRI for clinical display of anatomy and tumor rendering: preliminary results.
abstract: OBJECTIVE
  The objective of our study was to determine the clinical display thresholds of an ultrasound tomography prototype relative to MRI for comparable visualization of breast anatomy and tumor rendering.
  
  
  METHODS
  Thirty-six women were imaged with MRI and our ultrasound tomography prototype. The ultrasound tomography scan generated reflection, sound-speed, and attenuation images. The reflection images were fused with the components of the sound-speed and attenuation images that achieved thresholds to represent parenchyma or solid masses using an image arithmetic process. Qualitative and quantitative comparisons of MRI and ultrasound tomography clinical images were used to identify anatomic similarities and optimized thresholds for tumor shapes and volumes.
  
  
  RESULTS
  Thresholding techniques generated ultrasound tomography images comparable to MR images for visualizing fibrous stroma, parenchyma, fatty tissues, and tumors. In 25 patients, tumors were cancerous and in 11, benign. Optimized sound-speed thresholds of 1.46±0.1 and 1.52±0.03 km/s were identified to best represent the extent of fibroglandular tissue and solid masses, respectively. An arithmetic combination of attenuation images using a threshold of 0.16±0.04 dB/cm (mean±SD) further characterized benign from malignant masses. No significant difference in tumor volume was noted between benign or malignant masses by ultrasound tomography or MRI (p>0.1) using these universal thresholds.
  
  
  CONCLUSIONS
  Ultrasound tomography is able to image and render breast tissues in a manner comparable to MRI. Using universal ultrasound tomography threshold values for rendering the size and distribution of benign and malignant tissues appears feasible without IV contrast material.
authors.affiliation: Karmanos Cancer Institute, 3990 John R Rd, Harper Professional Bldg, Ste 710, Detroit, MI 48201, USA.
authors.forename: Bryan
authors.initials: B
authors.lastname: Ranger
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Littrup
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Duric
authors.forename: Priti
authors.initials: P
authors.lastname: Chandiwala-Mody
authors.forename: Cuiping
authors.initials: C
authors.lastname: Li
authors.forename: Steven
authors.initials: S
authors.lastname: Schmidt
authors.forename: Jessica
authors.initials: J
authors.lastname: Lupinacci
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000473:pathology; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D016217:Ultrasonography, Mammary / Q000379:methods*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA