Computerized Tomographic Angiography for Detection of Cerebral Vasospasm after Ruptured Intracranial Aneurysm
Jiranan Namyong MD*, Thaweesak Aurboonyawat MD*, Ekawut Chankaew MD*, Orasa Chawalparit MD**, Sirion Tritrakarn MD**, Prajak Srirabheebhat MD*, Varisa Wongbhanuwich MD*, Dittapong Songsaeng MD**, Julalak Boonma BSc**
Affiliation : * Division of Neurosurgery, Department of Surgery, Siriraj Hospital, Bangkok, Thailand ** Department of Radiology, Siriraj Hospital, Bangkok, Thailand
Objective : Digital subtraction angiography (DSA) is the gold standard to diagnose cerebral vasospasm but it is usually not
available due to lack of expertise and proper equipment. The present study aimed to compare the diagnostic accuracy of
brain computerized tomographic angiography (CTA) in detecting cerebral vasospasm after intracranial aneurysmal rupture.
Material and Method: Between January 2011 and October 2014, 20 patients who were suspected of cerebral vasospasm
after aneurysmal subarachnoid hemorrhage (SAH) were prospectively enrolled. All patients underwent brain CTA and DSA
within 24 hours after clinical onset of vasospasm. Separate reviewers independently reviewed the CTA and DSA.
Results : Twenty patients were enrolled, including 7 males and 13 females. The patient characteristics did not have any
relationship to the incidence of cerebral vasospasm. The CTA finding of vasospasm was well correlated to the DSA finding
(Kappa 0.793). Diagnostic accuracy and false negative of the CTA were 90% and 5%, respectively. Sensitivity of the CTA
was 94% and specificity was 100%. Positive predictive value of the CTA was 100% and negative predictive value was 66%.
The vessels that showed the most correlation between the CTA and DSA findings were left A1 (Kappa 0.684) and left A2
(Kappa 0.663) segments of anterior cerebral artery, and left M1 (Kappa 0.503) segment of middle cerebral artery. Both
CTA and DSA can detect mild vasospasm (<50% luminal stenosis) located proximal to the circle of Willis.
Conclusion : Compared to the DSA, the CTA can be used for detecting cerebral vasospasm in patients with ruptured
intracranial aneurysms with high sensitivity, specificity, and diagnostic accuracy.
Keywords : Computerized tomographic angiography (CTA), Cerebral vasospasm, Intracranial aneurysmal rupture, Digital subtraction angiography (DSA)
