Association of internal carotid artery injury with carotid canal fractures in patients with head trauma.
OBJECTIVE
The purpose of our study was to determine the degree to which carotid canal fracture and other CT findings are associated with internal carotid artery (ICA) injury in patients with head trauma.


METHODS
Three neuroradiologists retrospectively evaluated CT scans and cerebral angiograms of 43 patients who underwent cerebral angiography within 7 days after blunt cranial trauma over a 5-year period. Seventeen patients underwent unilateral and 26 had bilateral carotid angiography. Angiograms were evaluated for ICA injury and CT scans were evaluated for carotid canal fracture, brain contusion, subarachnoid hemorrhage, basilar skull fracture, subdural hematoma, soft-tissue swelling, sphenoid sinus air-fluid level, and other skull fracture. We recorded the number of true-positive (+CT, +angiogram), true-negative (-CT, -angiogram), false-positive (+CT, -angiogram), and false-negative (-CT, +angiogram) studies. We determined the sensitivity, specificity, positive predictive value, and negative predictive value for each CT finding.


RESULTS
We identified 21 carotid canal fractures in 17 patients. Eleven ICA injuries were seen in 10 patients. Six patients with ICA injury had a carotid canal fracture. The presence of a carotid canal fracture had a sensitivity of 60% and specificity of 67% for detection of injury to the ICA passing through that canal. These values were similar to those for other CT findings.


CONCLUSIONS
Sensitivity, specificity, positive predictive value, and negative predictive value of carotid canal fracture were only moderately good for determining the presence of ICA injury and were similar to other CT findings not typically associated with ICA injury.
York
Gerald
G
Department of Radiology, Box 3808, Duke University Medical Center, Durham, NC 27710, USA.
Barboriak
Daniel
D
Petrella
Jeffrey
J
DeLong
David
D
Provenzale
James M
JM
D000328:Adult; D020212:Carotid Artery Injuries / Q000000981:diagnostic imaging*; D002533:Cerebral Angiography; D016009:Chi-Square Distribution; D006259:Craniocerebral Trauma / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012887:Skull Fractures / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed; D014949:Wounds, Nonpenetrating / Q000000981:diagnostic imaging*