Frequency of adequate contrast opacification of the major intracranial venous structures with CT angiography in the setting of intracerebral hemorrhage: comparison of 16- and 64-section CT angiography techniques

Internal cerebral vein asymmetry on follow-up brain computed tomography after intravenous thrombolysis in acute anterior circulation ischemic stroke is associated with poor outcome

BACKGROUND

Identifying early predictors of functional outcome after acute ischemic stroke (AIS) is important for planning rehabilitation strategies. Internal cerebral veins (ICV) drain deep parts of brain, run parallel to each other, and consistently seen on computed tomography angiography (CTA). Even minor asymmetry in their filling can be identified. We hypothesized that venous drainage would be impaired in patients with acute occlusion of internal carotid artery or middle cerebral artery. Because systemic thrombolysis can alter the vascular findings, we evaluated the relationship between ICV asymmetry on follow-up CTA and functional outcome.

METHODS

Consecutive AIS patients treated with intravenous thrombolysis between 2007 and 2010 were included. ICV asymmetry was assessed by 2 independent blinded stroke neurologists/neuroradiologists. Functional outcome was assessed by the modified Rankin Scale (mRS) at 3 months, dichotomized as good (0-1) and poor (2-6). Data were analyzed for predictors of functional outcome.

RESULTS

Of 2238 patients with AIS, 226 (10.1%) anterior circulation AIS patients received intravenous thrombolysis. The median age was 65 years (range 19-92), 44% were men, and median National Institutes of Health Stroke Scale (NIHSS) score was 16 points (range 4-32). Hypertension was the commonest risk factor in 173 (76.5%) patients, whereas 78 (34.5%) had atrial fibrillation. ICV asymmetry on follow-up CTA was assessed in 103 (45.5%) patients. Admission NIHSS score (odds ratio [OR] 1.07; 95% confidence interval [CI] 1.079-1.201, P = .046), change in NIHSS score during first 24 hours (OR .737; 95% CI .672-.807, P < .0001), and ICV asymmetry on follow-up CTA (OR 20.3; 95% CI 4.67-52.07, P < .0001) independently predicted poor outcome at 3 months.

CONCLUSIONS

ICV asymmetry on follow-up CTA after intravenous thrombolysis is an early predictor of poor functional outcome.

Effect of region-of-interest placement in bolus tracking cerebral computed tomography angiography

INTRODUCTION

Premature or delayed triggering of semiautomatic contrast tracking during intracranial computed tomographic angiography can occur due to artifact from dense contrast in the superior vena cava or brachiocephalic veins near the anterior aortic arch. We determine if placement of bolus tracking region-of-interest in the posterior thoracic aorta can prevent suboptimal intracranial arterial opacification.

METHODS

Intracranial computed tomography angiographies from 80 patients performed on the same scanner were retrospectively evaluated. Thirty-seven consecutive patients with bolus tracking region-of-interest (ROI) placed in the anterior thoracic aorta (group A) and 43 consecutive patients with ROI placed in the posterior thoracic arch (group B) were identified. Two neuroradiologists scored the quality of intracranial computed tomography angiography on a four-point scale. Quantitative measurement of intracranial arterial opacification was also performed. The proportions of patients with poorest quality score as well as the proportions of the patients with the worst degree of intracranial arterial opacification (<10th percentile) were compared between groups A and B using two-sample proportion test.

RESULTS

Qualitative evaluation of the intracranial computed tomography angiography showed 4 (11%) patients in group A with poor quality (score of 1), while all patients in group B scored 2 or higher (p = 0.028). Seven (19%) patients in group A had the lowest quantitative score (mean arterial opacification < 10th percentile) while 1 (2.5%) patient in group B had the lowest score (p = 0.018).

CONCLUSION

Bolus tracking in the posterior thoracic aorta reduces the chance of suboptimal intracranial computed tomography angiography.

Advanced CT imaging in the evaluation of hemorrhagic stroke

Multidetector computed tomographic (CT) angiography is rapidly becoming a pivotal examination in the initial evaluation of patients with hemorrhagic stroke. This article provides an update of the literature on this dynamic topic, focusing on (1) the utility of CT angiography in the identification of hemorrhagic stroke patients who harbor an underlying vascular etiology and the role of the secondary intracerebral hemorrhage score, as well as (2) the clinical value of the CT angiography spot sign and spot sign score in patients with primary intracerebral hemorrhage.