title: Experimental study of intracranial hematoma detection with flat panel detector C-arm CT.
abstract: OBJECTIVE
  Intracranial hemorrhage is a commonly acknowledged complication of interventional neuroradiology procedures, and the ability to image hemorrhage at the time of the procedure would be very beneficial. A new C-arm system with 3D functionality extends the capability of C-arm imaging to include soft-tissue applications by facilitating the detection of low-contrast objects. We evaluated its ability to detect small intracranial hematomas in a swine model.
  
  
  METHODS
  Intracranial hematomas were created in 7 swine by autologous blood injection of various hematocrits (19%-37%) and volumes (1.5-5 mL). Four animals received intravascular contrast before obtaining autologous blood (group 1), and 3 did not (group 2). We scanned each animal by using the C-arm CT system, acquiring more than 500 images during a 20-second rotation through more than 200 degrees . Multiplanar reformatted images with isotropic resolution were reconstructed on the workstation by using product truncation, scatter, beam-hardening, and ring-artifact correction algorithms. The brains were harvested and sliced for hematoma measurement and compared with imaging findings.
  
  
  RESULTS
  Five intracranial hematomas were created in group 1 animals, and all were visualized. Six were created in group 2, and 3 were visualized. One nonvisualized hematoma was not confirmed at necropsy. All the others in both groups were confirmed. In group 1 (with contrast), small hematomas were detectable even when the hematocrit was 19%-20%. In group 2 (without contrast) C-arm CT was able to detect small hematomas (<1.0 cm(2)) created with hematocrits of 29%-37%. The area of hematoma measured from the C-arm CT data was, on average, within 15% of the area measured from harvested brain.
  
  
  CONCLUSIONS
  The image quality obtained with this implementation of C-arm CT was sufficient to detect experimentally created small intracranial hematomas. This capability should provide earlier detection of hemorrhagic complications that may occur during neurointerventional procedures.
authors.affiliation: Department of Radiology, Stanford University Medical Center, 300 Pasteur Dr, Stanford, CA 94305-5105, USA.
authors.forename: H
authors.initials: H
authors.lastname: Arakawa
authors.forename: M P
authors.initials: MP
authors.lastname: Marks
authors.forename: H M
authors.initials: HM
authors.lastname: Do
authors.forename: D M
authors.initials: DM
authors.lastname: Bouley
authors.forename: N
authors.initials: N
authors.lastname: Strobel
authors.forename: T
authors.initials: T
authors.lastname: Moore
authors.forename: R
authors.initials: R
authors.lastname: Fahrig
mesh_terms: D000818:Animals; D001777:Blood Coagulation; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging*; D003287:Contrast Media; D006400:Hematocrit; D006406:Hematoma / Q000000981:diagnostic imaging*; D007482:Iothalamate Meglumine; D034421:Sus scrofa; D015898:Tomography Scanners, X-Ray Computed; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D007482:Iothalamate Meglumine