PURPOSE: This study experimentally evaluated the slice sensitivity profile (SSP) and its relationship between acquisition angle, object size, and cone angle. The sensitivity profile metric was used to characterize a breast tomosynthesis system's resolution in the z-axis. The SSP was also measured on a prototype breast computed tomography (bCT) system. METHODS: The SSP was measured using brass disks placed within adipose tissue-equivalent breast phantoms. The digital tomosynthesis system (Selenia Dimensions, Hologic Corporation, Bedford, MA) acquires projection images over a 15° angular range and the bCT scanner acquires projection images over a 360° angular range. Angular ranges between 15° and 360° were studied by using a subset of the projection images acquired on the bCT scanner. The SSP was determined by measuring a background-corrected mean gray scale value as a function of the z-position (axis normal to the plane of the detector). RESULTS: The results show that SSP improves when the angular acquisition range is increased and the SSP approaches a delta function for angles greater than 180°. Smaller objects have a narrower SSP and the SSP is not significantly dependent on the cone angle. For a 2.5, 5, 10 mm disk, the full width at half maximum of the SSP was 35, 61, 115 mm, respectively, on the tomosynthesis system (at 15°) and was 0.5 mm for all disk diameters on the bCT scanner (at 360°). CONCLUSIONS: The SSP is dependent on object size and angular acquisition range. These dependencies are overcome once the angular acquisition range is increased beyond 180°.
PURPOSE: This study experimentally evaluated the slice sensitivity profile (SSP) and its relationship between acquisition angle, object size, and cone angle. The sensitivity profile metric was used to characterize a breast tomosynthesis system's resolution in the z-axis. The SSP was also measured on a prototype breast computed tomography (bCT) system. METHODS: The SSP was measured using brass disks placed within adipose tissue-equivalent breast phantoms. The digital tomosynthesis system (Selenia Dimensions, Hologic Corporation, Bedford, MA) acquires projection images over a 15° angular range and the bCT scanner acquires projection images over a 360° angular range. Angular ranges between 15° and 360° were studied by using a subset of the projection images acquired on the bCT scanner. The SSP was determined by measuring a background-corrected mean gray scale value as a function of the z-position (axis normal to the plane of the detector). RESULTS: The results show that SSP improves when the angular acquisition range is increased and the SSP approaches a delta function for angles greater than 180°. Smaller objects have a narrower SSP and the SSP is not significantly dependent on the cone angle. For a 2.5, 5, 10 mm disk, the full width at half maximum of the SSP was 35, 61, 115 mm, respectively, on the tomosynthesis system (at 15°) and was 0.5 mm for all disk diameters on the bCT scanner (at 360°). CONCLUSIONS: The SSP is dependent on object size and angular acquisition range. These dependencies are overcome once the angular acquisition range is increased beyond 180°.
Authors: S Suryanarayanan; A Karellas; S Vedantham; S J Glick; C J D'Orsi; S P Baker; R L Webber Journal: Acad Radiol Date: 2000-12 Impact factor: 3.173
Authors: Nicolas D Prionas; Karen K Lindfors; Shonket Ray; Shih-Ying Huang; Laurel A Beckett; Wayne L Monsky; John M Boone Journal: Radiology Date: 2010-09 Impact factor: 11.105
Authors: Jodie A Christner; Karl Stierstorfer; Andrew N Primak; Christian D Eusemann; Thomas G Flohr; Cynthia H McCollough Journal: Med Phys Date: 2010-02 Impact factor: 4.071
Authors: L Chen; J M Boone; C K Abbey; J Hargreaves; C Bateni; K K Lindfors; K Yang; A Nosratieh; A Hernandez; P Gazi Journal: Phys Med Biol Date: 2015-03-31 Impact factor: 3.609
Authors: Willi A Kalender; Daniel Kolditz; Christian Steiding; Veikko Ruth; Ferdinand Lück; Ann-Christin Rößler; Evelyn Wenkel Journal: Eur Radiol Date: 2016-06-15 Impact factor: 5.315