Diagnosing brain death by CT perfusion and multislice CT angiography.
BACKGROUND
Although the diagnosis of brain death (BD) is usually based on clinical criteria, in sedated patients, ancillary techniques are needed. This study was designed to assess the accuracy of cerebral multislice computed tomographic angiography (CTA) and CT perfusion (CTP) in diagnosing BD.


METHODS
Prospective observational study in 27 BD patients.


RESULTS
All patients were diagnosed as BD based on clinical and electroencephalogram findings. After BD diagnosis, CTP was performed followed by 64-detector multislice CTA from the aortic arch to the vertex. Images were reconstructed from 0.5 mm sections. In 24 patients, a lack of cerebral blood flow (CBF) was detected by CTP, and CTA revealed luminal narrowing of the internal carotid artery in the neck and absence of anterior and posterior intracranial circulation (sensitivity 89%). CTA detected CBF exclusively in extracranial portions of the internal carotid and vertebral arteries. Two patients with anoxic brain injury and decompressive craniectomy showed CBF in the CTA such that the CTP results were considered false negatives, given BD had been confirmed by clinical and EEG findings, along with evoked potentials. In one clinically BD patient, in whom an alpha rhythm was detected in the electroencephalogram, CBF was only observed in the intracranial internal carotid with no posterior circulation noted. This patient was therefore considered exclusively brain stem dead.


CONCLUSIONS
The radiological protocol used shows a high sensitivity and excellent specificity for detecting the cerebral circulatory arrest that accompanies BD. As a rapid, non-invasive, and widely available technique it is a promising alternative to conventional 4-vessel angiography.
Escudero
Dolores
D
Department of Intensive Care Medicine, Hospital Universitario Central de Asturias, C/Celestino Villamil s/n, 33006 Oviedo, Spain. dolores.escudero@sespa.princast.es
Otero
Jesús
J
Marqués
Lara
L
Parra
Diego
D
Gonzalo
José Antonio
JA
Albaiceta
Guillermo M
GM
Cofiño
Luis
L
Blanco
Armando
A
Vega
Pedro
P
Murias
Eduardo
E
Meilan
Angela
A
Roger
Ricardo López
RL
Taboada
Francisco
F
D000328:Adult; D000368:Aged; D000513:Alpha Rhythm; D001783:Blood Flow Velocity; D001921:Brain / Q000000981:diagnostic imaging*; D001926:Brain Death / Q000175:diagnosis*; D002533:Cerebral Angiography / Q000379:methods; D002560:Cerebrovascular Circulation; D004569:Electroencephalography; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods; D055815:Young Adult