Related Experiment Video
Updated: Jul 28, 2026
Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli
Published on: September 25, 2016
Computed tomography angiography in the diagnosis of brain death: a systematic review and meta-analysis
Andreas H Kramer1, Derek J Roberts
1Departments of Critical Care Medicine & Clinical Neurosciences, Foothills Hospital, University of Calgary, McCaig Tower, 3134 Hospital Drive N.W., Calgary, AB, T2N 2T9, Canada, andreas.kramer@calgaryhealthregion.ca.
Insights
Computed tomography angiography (CTA) shows variable accuracy for diagnosing brain death. Absence of internal cerebral vein opacification is the most promising CTA criterion, but further validation is needed before routine use.
Area of Science:
- Neurology
- Radiology
- Critical Care Medicine
Background:
- Clinical diagnosis of brain death can be challenging due to physiological instability.
- Computed tomography angiography (CTA) is a potential ancillary tool for confirming brain death.
- The diagnostic accuracy of CTA for brain death requires further clarification.
Purpose of the Study:
- To evaluate the diagnostic accuracy of CTA in confirming brain death.
- To compare CTA findings with established clinical and radiographic criteria for brain death.
Main Methods:
- Systematic review and meta-analysis of studies comparing CTA with brain death diagnostic methods.
- Searched MEDLINE, EMBASE, and CENTRAL databases.
- Calculated pooled sensitivity and performed subgroup analyses and meta-regression.
Main Results:
- Pooled sensitivity for CTA was 62% (venous phase) and 84% (arterial phase) for complete intracranial vessel opacification.
- Sensitivity reached 99% when absence of internal cerebral vein opacification was the criterion.
- CTA sensitivity was not affected by reference standards or patient diagnosis (stroke vs. trauma).
- Specificity of CTA could not be reliably determined.
Conclusions:
- Persistent opacification of proximal intracranial vessels is common in patients meeting brain death criteria.
- The specificity of CTA for brain death diagnosis remains inadequately assessed.
- Routine CTA use is not recommended until refined criteria are validated; absence of internal cerebral vein opacification is a promising criterion.
Background:
Physiological instability and confounding factors may interfere with the clinical diagnosis of brain death. Computed tomography angiography (CTA) has been suggested as a potential ancillary test for confirmation of brain death, but its diagnostic accuracy remains unclear.
Methods:
We searched MEDLINE, EMBASE, and CENTRAL for studies comparing CTA with other accepted methods of diagnosing brain death (clinical or radiographic). Summary estimates of diagnostic accuracy were computed using random effects models. Subgroup analyses and meta-regression were performed to assess associations between CTA sensitivity and study or patient characteristics.
Results:
Twelve studies, involving 541 patients, were included. If the CTA criterion for brain death was complete lack of opacification of intracranial vessels, then the pooled sensitivity was 62 % (50-74 %) for venous phase and 84 % (75-94 %) for arterial phase imaging. The sensitivity of CTA was higher when the criterion for brain death involved absence of opacification of internal cerebral veins, either alone (99 %, 97-100 %) or in combination with lack of flow to the distal middle cerebral artery branches (85 %, 77-93 %). CTA sensitivity was not influenced by different reference standards (clinical vs. radiographic) or predominant diagnostic category (stroke vs. brain trauma). Specificity of CTA could not be adequately determined from the existing data.
Conclusion:
Many patients who progress to brain death by accepted clinical or radiographic criteria have persistent opacification of proximal intracranial vessels when CTA is performed. The specificity of CTA in the diagnosis of brain death has not been adequately assessed. Routine use of CTA as an ancillary test in the diagnosis of brain death is therefore not recommended until diagnostic criteria have undergone further refinement and prospective validation. Absence of opacification of the internal cerebral veins appears to be the most promising angiographic criterion.
More Related Videos
08:12A Volumetric Method for Quantification of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage
Published on: July 28, 2018
08:36Multi-Tracer Studies of Brain Oxygen and Glucose Metabolism Using a Time-of-Flight Positron Emission Tomography-Computed Tomography Scanner
Published on: June 7, 2024
Related Concept Videos
01:10Computed Tomography
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...
01:14Brain Imaging
These technologies include computerized axial tomography (CAT or CT scans), positron-emission tomography (PET scans), magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), and Transcranial Magnetic Stimulation (TMS).
01:28Imaging Studies for Cardiovascular System V: CT