Systematic combined noncontrast CT–CT angiography in the management of unexplained nontraumatic coma

Published:January 23, 2013DOI:



      Nontraumatic impaired consciousness is a common issue in emergency departments with a serious but widely variable prognosis.

      Study objectives

      The aim of this prospective study was to evaluate the ability of systematic combined noncontrast computed tomography (NCCT)/computed tomography angiography (CTA) imaging, firstly to provide a neurologic prognosis and secondly to ensure early detection of basilar artery occlusion (BAO), in unexplained nontraumatic impaired consciousness management.


      Combined NCCT/CTA imaging was performed on 65 patients with impaired consciousness and no history of trauma prospectively over 14 months in a single center. Images were assessed based on visual and quantitative criteria. Clinical outcome was assessed using the modified Rankin Scale at 3 months. Statistical analysis aimed to identify the prognostic value of combined NCCT/CTA imaging and its ability for early BAO detection.


      This study shows that combined NCCT/CTA imaging was a significant predictor of poor neurological outcome, with a positive predictive value of 94.6%. The combination was also crucial for early detection of BAO, given that 42.8% of cases were misdiagnosed with NCCT alone. Basilar artery occlusion represented 10.8% of all unexplained nontraumatic impaired consciousness.


      Systematic combined NCCT/CTA imaging is an efficient tool for predicting poor neurologic prognosis in cases of unexplained nontraumatic impaired consciousness and is also essential for detecting BAO.
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