title: Influence of selective photon shield combined with sinogram-affirmed iterative reconstruction on image quality and radiation dose during dual-energy CT angiography-mediated diagnosis of intracranial aneurysms.
abstract: OBJECTIVE
  To investigate the influence of a selective photon shield (SPS) combined with sinogram-affirmed iterative reconstruction (SAFIRE) on image quality and radiation dose during application of dual-energy CT angiography (CTA) for diagnosis of intracranial aneurysms.
  
  
  METHODS
  We retrospectively reviewed clinical data for 80 patients with diagnoses of spontaneous subarachnoid hemorrhage. All patients underwent three-dimensional digital subtraction angiography scans within 1 week after CTA. Data for patients in the conventional method group were subjected to filtered-back-projection reconstruction, while data for patients in the experimental method group were subjected to SAFIRE reconstruction. Image quality and scanning radiation dose were evaluated.
  
  
  RESULTS
  Background noise was significantly lower in the experimental method group than in the conventional method group, while the mean CT value did not differ between the groups. Signal-to-noise ratios were significantly higher in the experimental method group than in the conventional method group. However, the average CT value, contrast-to-noise ratio, and image quality scores did not differ between groups. All scores indicated acceptability for clinical diagnosis. The dose index of volume and effective dose were significantly lower in the experimental method group than in the conventional method group. Surgical verification showed that the detection rates in the experimental and conventional method groups were 100% (29/29) and 96% (25/26), respectively.
  
  
  CONCLUSIONS
  SPS combined with SAFIRE applied for analysis of dual-energy CTA data improved the quality of CT images, reduced the radiation dosage, and increased diagnostic accuracy.
  
  
  CONCLUSIONS
  SPS combined with SAFIRE may improve the accuracy of diagnosis of intracranial aneurysms.
authors.affiliation: a Medical Imaging Department , Kunming Medical University , Kunming , China.
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.affiliation: b Department of Cardiology, Shanghai Renji Hospital, School of Medicine , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Gao
authors.affiliation: a Medical Imaging Department , Kunming Medical University , Kunming , China.
authors.forename: Ya-Ying
authors.initials: YY
authors.lastname: Yang
authors.affiliation: a Medical Imaging Department , Kunming Medical University , Kunming , China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D000072226:Computed Tomography Angiography / Q000379:methods*; D003287:Contrast Media / Q000378:metabolism; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
chemical_list: D003287:Contrast Media
keywords: X-ray computed tomography; dosage; image quality; intracranial aneurysm; radiation; tomography