Global and focal cerebral perfusion after aneurysmal subarachnoid hemorrhage in relation with delayed cerebral ischemia.
BACKGROUND
The pathogenesis of delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is unclear. We assessed whether DCI relates to focal or global cerebral perfusion on admission and on follow-up imaging.


METHODS
Twenty-seven SAH patients underwent computed tomography (CT) perfusion (CTP) on admission and at clinical deterioration or 1 week after admission in clinically stable patients. We compared global and focal (least perfused territory) perfusion in patients with DCI (n = 12), clinically stable patients (n = 7), and patients with non-DCI-related deterioration (n = 8).


RESULTS
Global cerebral blood flow (CBF) increased on follow-up: 29% (95% confidence interval (CI) 15% to 43%) in patients with DCI, 12% (95%CI -1% to 25%) in stable patients, and 20% (95%CI 4% to 36%) in patients with non-DCI-related deterioration. Focal CBF decreased in patients with DCI, (-23%; 95%CI -58% to 12%) but increased in patients with non-DCI-related deterioration (23%; 95%CI -26% to 55%) and stable patients (7%; 95%CI -30% to 45%).On follow-up, global CBF was lower in patients with DCI (70.0 ml per 100 g/min) than in clinically stable patients (81.6; difference 11.6; 95%CI 0.8 to 22.5 ml per 100 g/min) but comparable to patients with non-DCI-related deterioration (67.6; difference -2.4; 95%CI -11.9 to 7.2 ml per 100 g/min). Focal CBF was lower in patients with DCI (30.7) than in clinically stable patients (53.6; difference 22.9; 95%CI 5.1 to 40.6 ml per 100 g/min) and patients with non-DCI-related deterioration (46.6; difference 15.9; 95%CI -2.6 to 28.4 ml per 100 g/min)


CONCLUSIONS
Our results suggest that DCI is more likely a focal than a global process.
Rijsdijk
M
M
Department of Radiology, University Medical Center Utrecht, GA Utrecht, The Netherlands.
van der Schaaf
I C
IC
Velthuis
B K
BK
Wermer
M J
MJ
Rinkel
G J E
GJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017542:Aneurysm, Ruptured / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D013997:Time Factors; D014057:Tomography, X-Ray Computed