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CT Angiography in the Diagnosis of Brain Death.

Sawicki M, Bohatyrewicz R, Walecka A, Sołek-Pastuszka J, Rowiński O, Walecki J - Pol J Radiol (2014)

Bottom Line: In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful.Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death.Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada).

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Imaging and Interventional Radiology, Pomeranian Medical University in Szczecin, Szczecin, Poland.

ABSTRACT
Summary Brain death is defined as the irreversible cessation of functioning of the entire brain, including the brainstem. Brain death is principally established using clinical criteria including coma, absence of brainstem reflexes and loss of central drive to breathe assessed with apnea test. In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful. The objective of ancillary tests in the diagnosis of brain death is to demonstrate the absence of cerebral electrical activity (EEG and evoked potentials) or cerebral circulatory arrest. In clinical practice catheter cerebral angiography, perfusion scintigraphy, transcranial Doppler sonography, CT angiography and MR angiography are used. Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death. CT angiography has recently attracted attention as a promising alternative to catheter angiography - a reference test in the diagnosis of brain death. Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada). This paper reviews technique, characteristic findings and criteria for the diagnosis of cerebral circulatory arrest in CT angiography.

No MeSH data available.


Related in: MedlinePlus

Positive results of CTA in the diagnosis of BD: (A) – 10-mm MIP in the coronal plane shows stasis filling with delayed opacification of proximal MCAs (white arrows); please note the simultaneous opacification of the superficial temporal arteries (black arrows) (B) – 10-mm MIP in the coronal plane shows no intracranial filling; these findings confirm the diagnosis of BD.
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f2-poljradiol-79-417: Positive results of CTA in the diagnosis of BD: (A) – 10-mm MIP in the coronal plane shows stasis filling with delayed opacification of proximal MCAs (white arrows); please note the simultaneous opacification of the superficial temporal arteries (black arrows) (B) – 10-mm MIP in the coronal plane shows no intracranial filling; these findings confirm the diagnosis of BD.

Mentions: Unfortunately, CTA findings have not been studied in non-brain-dead patients with intracranial hypertension yet. The earliest sign of cerebral circulatory arrest in CTA is a lack of opacification of the deep veins – the internal cerebral veins (ICV) and the great cerebral vein (GCV, vein of Galen). The sensitivity of this finding in the diagnosis of cerebral circulatory arrest in CTA is 98–100% [4,6–8]. A lack of opacification of cortical branches of the middle cerebral arteries (MCA-M4) is a slightly less sensitive indicator of cerebral circulatory arrest with a sensitivity of 86–100% [6,7]. The basilar artery (BA) and cortical branches of the posterior cerebral arteries (PCA-P2) are more frequently opacified in cerebral circulatory arrest than MCA-M4. Their sensitivities are 83–94% and 79%, respectively [4,6,9]. The least sensitive finding of cerebral circulatory arrest is a lack of opacification of cortical branches of the anterior cerebral artery (ACA-A3, pericallosal artery) with a sensitivity of 64% [6]. Such a sequence is explained by the highest susceptibility of cortical branches of the MCA to the intracranial hypertension and the lowest cerebral perfusion pressure (CPP) in these arteries – see Figure 1. In the course of cerebral circulatory arrest, proximal segments of the cerebral arteries may show opacification for some time – Figure 2A. These arteries appear as thin and their filling is delayed and weak [10]. Intracranial stasis of contrast is observed with its extremely slow elimination through arteriovenous shunts and extravasation due to the interrupted blood-brain barrier. The last sign of cerebral circulatory arrest is intracranial non-filling – see Figure 2B.


CT Angiography in the Diagnosis of Brain Death.

Sawicki M, Bohatyrewicz R, Walecka A, Sołek-Pastuszka J, Rowiński O, Walecki J - Pol J Radiol (2014)

Positive results of CTA in the diagnosis of BD: (A) – 10-mm MIP in the coronal plane shows stasis filling with delayed opacification of proximal MCAs (white arrows); please note the simultaneous opacification of the superficial temporal arteries (black arrows) (B) – 10-mm MIP in the coronal plane shows no intracranial filling; these findings confirm the diagnosis of BD.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4237071&req=5

f2-poljradiol-79-417: Positive results of CTA in the diagnosis of BD: (A) – 10-mm MIP in the coronal plane shows stasis filling with delayed opacification of proximal MCAs (white arrows); please note the simultaneous opacification of the superficial temporal arteries (black arrows) (B) – 10-mm MIP in the coronal plane shows no intracranial filling; these findings confirm the diagnosis of BD.
Mentions: Unfortunately, CTA findings have not been studied in non-brain-dead patients with intracranial hypertension yet. The earliest sign of cerebral circulatory arrest in CTA is a lack of opacification of the deep veins – the internal cerebral veins (ICV) and the great cerebral vein (GCV, vein of Galen). The sensitivity of this finding in the diagnosis of cerebral circulatory arrest in CTA is 98–100% [4,6–8]. A lack of opacification of cortical branches of the middle cerebral arteries (MCA-M4) is a slightly less sensitive indicator of cerebral circulatory arrest with a sensitivity of 86–100% [6,7]. The basilar artery (BA) and cortical branches of the posterior cerebral arteries (PCA-P2) are more frequently opacified in cerebral circulatory arrest than MCA-M4. Their sensitivities are 83–94% and 79%, respectively [4,6,9]. The least sensitive finding of cerebral circulatory arrest is a lack of opacification of cortical branches of the anterior cerebral artery (ACA-A3, pericallosal artery) with a sensitivity of 64% [6]. Such a sequence is explained by the highest susceptibility of cortical branches of the MCA to the intracranial hypertension and the lowest cerebral perfusion pressure (CPP) in these arteries – see Figure 1. In the course of cerebral circulatory arrest, proximal segments of the cerebral arteries may show opacification for some time – Figure 2A. These arteries appear as thin and their filling is delayed and weak [10]. Intracranial stasis of contrast is observed with its extremely slow elimination through arteriovenous shunts and extravasation due to the interrupted blood-brain barrier. The last sign of cerebral circulatory arrest is intracranial non-filling – see Figure 2B.

Bottom Line: In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful.Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death.Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada).

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Imaging and Interventional Radiology, Pomeranian Medical University in Szczecin, Szczecin, Poland.

ABSTRACT
Summary Brain death is defined as the irreversible cessation of functioning of the entire brain, including the brainstem. Brain death is principally established using clinical criteria including coma, absence of brainstem reflexes and loss of central drive to breathe assessed with apnea test. In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful. The objective of ancillary tests in the diagnosis of brain death is to demonstrate the absence of cerebral electrical activity (EEG and evoked potentials) or cerebral circulatory arrest. In clinical practice catheter cerebral angiography, perfusion scintigraphy, transcranial Doppler sonography, CT angiography and MR angiography are used. Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death. CT angiography has recently attracted attention as a promising alternative to catheter angiography - a reference test in the diagnosis of brain death. Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada). This paper reviews technique, characteristic findings and criteria for the diagnosis of cerebral circulatory arrest in CT angiography.

No MeSH data available.


Related in: MedlinePlus