title: Image quality and artefact generation post-cerebral aneurysm clipping using a 64-row multislice computer tomography angiography (MSCTA) technology: A retrospective study and review of the literature.
abstract: OBJECTIVE
  Computed tomography angiography (CTA) is a time and cost saving investigation for postoperative evaluation of clipped cerebral aneurysm patients. A retrospective study was conducted to analyse image quality and artefact generation due to implanted aneurysm clips using a new technology.
  
  
  METHODS
  MSCTA was performed pre- and postoperatively using a Philips Brilliance 64-detector-row CT scanner. Altogether, 32 clipping sites were analysed in 27 patients (11 female and 16 male, mean ages 52a, from 24 to 72 years). Clip number per aneurysm was 2.3 mean (from 1 to 4), 54 clips were made of titanium alloy and 5 of cobalt alloy.
  
  
  RESULTS
  Altogether, image quality was rated 1.8 mean, using a scale from 1 (very good) to 5 (unserviceable) and clip artefacts were rated 2.4 mean, using a 5 point rating scale (1 no artefacts, 5 unserviceable due to artefacts). A significant loss of image quality and rise of artefacts was found when using cobalt alloy clips (1.4 versus 4.2 and 2.1 versus 4.0). In 72% of all investigations, an excellent image quality was found. Excluding the cobalt clip group, 85% of scans showed excellent image quality. Artefacts were absent or minimal (grade 1 or 2) in 69% of all investigations and in 81% in the pure titanium clip group. In 64-row MSCTA of good image quality with low artefacts, it was possible to detect small aneurysm remnants of 2mm size in individual patients.
  
  
  CONCLUSIONS
  By using titanium alloy clips, in our study up to 85% of postoperative CTA images were of excellent quality with absent or minimal artefacts in 81% and seem adequate to detect small aneurysm remnants.
authors.affiliation: Department of Neurosurgery, Academic Teaching Hospital Feldkirch, Carinagasse 47, A-6807 Feldkirch, Austria. iris.zachenhofer@lkhf.at
authors.forename: Iris
authors.initials: I
authors.lastname: Zachenhofer
authors.forename: Manfred
authors.initials: M
authors.lastname: Cejna
authors.forename: Antonius
authors.initials: A
authors.lastname: Schuster
authors.forename: Markus
authors.initials: M
authors.lastname: Donat
authors.forename: Karl
authors.initials: K
authors.lastname: Roessler
mesh_terms: D000497:Alloys; D015901:Angiography, Digital Subtraction / Q000295:instrumentation*; D016477:Artifacts; D002533:Cerebral Angiography / Q000295:instrumentation; D004867:Equipment Design; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D019635:Neurosurgical Procedures / Q000295:instrumentation; D012189:Retrospective Studies; D013525:Surgical Instruments; D013672:Technology / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed / Q000592:standards
chemical_list: D000497:Alloys