title: Subtracted 3D CT angiography for the evaluation of intracranial aneurysms in 256-slice multidetector CT: usefulness of the 80-kVp plus compact contrast medium bolus protocol.
abstract: OBJECTIVE
  To evaluate the usefulness of an 80-kVp and compact contrast material protocol for arterial phase subtracted cerebral 3D-CTA using 256-slice multidetector CT.
  
  
  METHODS
  Thirty-two patients underwent CT with 100 kVp and received a contrast dose of 370 mgI/kg body weight over 15 s (protocol A). Thirty-three patients underwent CT with 100 kVp and received a contrast dose of 296 mgI/kg body weight over 10 s (protocol B). Thirty-three other patients underwent CT with 80 kVp and received a contrast medium dose of 296 mgI/kg body weight over 10 s (protocol C). We compared the arterial attenuation and contrast noise ratio (CNR) of each protocol. Two independent readers assessed overall image quality.
  
  
  RESULTS
  Arterial attenuation was significantly higher under protocols A (418.6 ± 71.1 HU) and C (442.7 ± 79.3 HU) than under protocol B (355.8 ± 107.2 HU; P < 0.05). The CNR of protocol C (26.1 ± 6.1) was higher than that of protocol A (20.7 ± 8.4; P < 0.05). The overall image quality of protocol A was higher than that of protocol C (P < 0.01).
  
  
  CONCLUSIONS
  The 80-kVp plus compact contrast protocol is well suited to arterial phase subtracted cerebral 3D-CTA without confounding venous enhancement.
  
  
  CONCLUSIONS
  • Subtracted 3D CT angiography is useful in the evaluation of intracranial aneurysms. • A compact contrast material protocol increased arterial attenuation without venous contamination. • Low-kVp CT compensated for the decreased amount of contrast medium. • An 80-kVp CT with a compact enhancement bolus provides good intracranial 3D-CT angiography.
authors.affiliation: Diagnostic Radiology, Amakusa Medical Center, kameba 854-1, Amakusa, Kumamoto, 863-0046, Japan, masafkidoh@yahoo.co.jp.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kidoh
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakaura
authors.forename: Takaaki
authors.initials: T
authors.lastname: Ogata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Takashima
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshikawa
authors.forename: Shouzaburou
authors.initials: S
authors.lastname: Uemura
authors.forename: Kazunori
authors.initials: K
authors.lastname: Harada
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Yamashita
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D007275:Injections, Intravenous; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media