OBJECTIVES: To assess the efficacy of fine focal spot imaging in calcification beam-hardening artefact reduction and vessel clarity on CT abdominal angiography (CTAA). METHODS: Adult patients of any age and gender who presented for CTAA were included. Thirty-nine patients were examined with a standard focal spot size (SFSS) of 1 × 1 mm in the first 3 months while 31 consecutive patients were examined with a fine focal spot size (FFSS) of 1 × 0.5 mm in the following 3 months. Vessel clarity and calcification beam-hardening artefacts of the abdominal aorta, celiac axis, superior mesenteric artery, inferior mesenteric artery, renal arteries, and iliac arteries were assessed using a 5-point grading scale by two blinded radiologists randomly. RESULTS: Cohen's Kappa test indicated that on average, there was substantial agreement among reviewers for vessel wall clarity and calcification artefact grading. Mann-Whitney test showed that there was a significant difference between the two groups, with FFSS performing significantly better for vessel clarity (U, 6481.50; p < 0.001; r, 0.73) and calcification artefact reduction (U, 1916; p < 0.001; r, 0.77). CONCLUSION: Fine focus CT angiography produces images with better vessel wall clarity and less vessel calcification beam-hardening artefact. KEY POINTS: Focal spot size affects the spatial resolution of a CT system. Fine focus CTAA produces images with improved vessel wall clarity. Fine focus CTAA is associated with fewer calcification beam-hardening artefacts. Fine focus CTAA may improve accuracy in assessment of luminal stenosis.
OBJECTIVES: To assess the efficacy of fine focal spot imaging in calcification beam-hardening artefact reduction and vessel clarity on CT abdominal angiography (CTAA). METHODS: Adult patients of any age and gender who presented for CTAA were included. Thirty-nine patients were examined with a standard focal spot size (SFSS) of 1 × 1 mm in the first 3 months while 31 consecutive patients were examined with a fine focal spot size (FFSS) of 1 × 0.5 mm in the following 3 months. Vessel clarity and calcification beam-hardening artefacts of the abdominal aorta, celiac axis, superior mesenteric artery, inferior mesenteric artery, renal arteries, and iliac arteries were assessed using a 5-point grading scale by two blinded radiologists randomly. RESULTS: Cohen's Kappa test indicated that on average, there was substantial agreement among reviewers for vessel wall clarity and calcification artefact grading. Mann-Whitney test showed that there was a significant difference between the two groups, with FFSS performing significantly better for vessel clarity (U, 6481.50; p < 0.001; r, 0.73) and calcification artefact reduction (U, 1916; p < 0.001; r, 0.77). CONCLUSION: Fine focus CT angiography produces images with better vessel wall clarity and less vessel calcification beam-hardening artefact. KEY POINTS: Focal spot size affects the spatial resolution of a CT system. Fine focus CTAA produces images with improved vessel wall clarity. Fine focus CTAA is associated with fewer calcification beam-hardening artefacts. Fine focus CTAA may improve accuracy in assessment of luminal stenosis.
Authors: Ugur Bozlar; Torel Ogur; Patrick T Norton; Minhaj S Khaja; Jaime All; Klaus D Hagspiel Journal: AJR Am J Roentgenol Date: 2013-10 Impact factor: 3.959
Authors: Rody Ouwendijk; Marc C J M Kock; Lukas C van Dijk; Marc R H M van Sambeek; Theo Stijnen; M G Myriam Hunink Journal: Radiology Date: 2006-09-11 Impact factor: 11.105
Authors: C Thomas; A Korn; B Krauss; D Ketelsen; I Tsiflikas; A Reimann; H Brodoefel; C D Claussen; A F Kopp; U Ernemann; M Heuschmid Journal: Eur J Radiol Date: 2009-06-10 Impact factor: 3.528