title: C-arm cone beam computed tomography needle path overlay for image-guided procedures of the spine and pelvis.
abstract: BACKGROUND
  The aim of this study is to report our early clinical experience using C-arm cone beam computed tomography with fluoroscopic overlay for image guidance during percutaneous needle procedures of the spine and pelvis.
  
  
  METHODS
  Twelve consecutive patients (four female and eight male patients; mean age, 64 years; range, 47-74 years; SD ± 7.6 years) who underwent percutaneous biopsy of the spine and pelvis for suspected metastasis (n = 12), spondylodiscitis (n = 6), abscess (n = 5) or bone tumour (n = 1) were prospectively included between March 2009 and November 2010. The procedures were performed on the Allura Xper FD20/20 (Philips, Best, the Netherlands) using cone beam computed tomography (XperCT) with the C-arm combined with fluoroscopic overlay for needle guidance. Based on an initial XperCT, entry and target points were defined using dedicated guidance software (XperGuide). The needle path was visualised in various reconstructed planes and could be adjusted when considered necessary. For percutaneous interventions, the entry view (overlay of entry and target point in the bull's eye fashion), the progression view (perpendicular to the entry view) as well as two additional views could automatically be piloted to with the C-arm system. Needle navigation was supported by a biopsy guidance device (Seestar, Radi, Uppsala, Sweden). Correct needle positioning was confirmed with a second XperCT acquisition. Technical success was defined as any target point reached via the planned needle trajectory with a distance of final needle tip within 5 mm of the planned target point in any direction.
  
  
  RESULTS
  In all 12 patients, target areas could be defined based on XperCT data. In 11 of 12 (92%) cases, the target point was successfully reached on the planned trajectory with a mean error of 2.8 mm (range, 0.5-9.4 mm; SD, 2.4 mm). No peri- or post-interventional complications occurred.
  
  
  CONCLUSIONS
  XperCT-guided interventions with the XperGuide system seem a safe and reliable tool for percutaneous needle interventions of the spine and pelvis. The advantage of the technique when compared to CT- or fluoroscopy-guided interventions needs to be determined in a comparative study of a larger scale.
authors.affiliation: Department of Neuroradiology, Neurocentre, University Hospital Freiburg, Breisgauer Strasse 64, 79106, Freiburg, Germany.
authors.forename: Simon C
authors.initials: SC
authors.lastname: Leschka
authors.forename: Drazenko
authors.initials: D
authors.lastname: Babic
authors.forename: Samer
authors.initials: S
authors.lastname: El Shikh
authors.forename: Christine
authors.initials: C
authors.lastname: Wossmann
authors.forename: Martin
authors.initials: M
authors.lastname: Schumacher
authors.forename: Christian A
authors.initials: CA
authors.lastname: Taschner
mesh_terms: D000038:Abscess / Q000000981:diagnostic imaging / Q000473:pathology*; D000368:Aged; D001707:Biopsy, Needle / Q000379:methods*; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D003287:Contrast Media; D015299:Discitis / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D011860:Radiography, Abdominal / Q000379:methods*; D015641:Radiography, Interventional / Q000379:methods*
chemical_list: D003287:Contrast Media