Evaluation of CT angiography for visualisation of the lenticulostriate artery: difference between normotensive and hypertensive patients

Abstract

Objective: High-resolution CT angiography (CTA) is currently available using multidetector row CT (MDCT); however, its use for small artery visualisation has been limited. To evaluate its capability, we investigated CTA visualisation for difference in number of the lenticulostriate artery (LSA) branches between normotensive and hypertensive patients, because hypertension is a major cause of LSA damage.

Methods: This was a retrospective study evaluating cerebrovascular CTA at our hospital conducted from February 2008 to June 2009 under approval of the institutional review board. 117 patients (39 males and 78 females, 19-88 years old) were included. CTA was conducted using a 64 channel MDCT. Total numbers of LSA branches were examined for differences by age with regression analysis and the presence or absence of hypertension and/or aneurysm using two-sample t-tests. A p-value <0.016 was considered statistically significant after correction for multiple comparisons. A multiple variable analysis of three factors was also conducted.

Results: The average number of LSA branches was 3.6 [95% confidence interval (CI) 3.0-4.1] and 4.4 (95% CI 4.1-4.7), respectively, for a patient with and without history of hypertension, and the difference was statistically significant (p=0.013). The difference was approximately one branch in the multiple variable analysis. No significant correlation was observed for age and no significant difference was observed for the presence or absence of aneurysms.

Conclusions: Contrast-enhanced CTA can visualise significant differences in the number of LSA branches among patients with and without hypertension. Advances in knowledge Current high-resolution CTA can visualise LSA well, which enables finding a difference in the LSA between normotensive subjects and hypertensive patients.

Figure 1

An accepted case with an aneurysm after clipping. Clipping does not deteriorate visualisation of MCA to branches of the lenticulostriate artery.

Figure 2

Tracing a lenticulostriate artery branch using multiplaner reformatted images. Each branch visualised in maximum intensity projection images was traced in three orthogonal directions (coronal, axial and sagittal) from the origin from the middle cerebral artery (arrows).

Figure 3

Average number of lenticulostriate artery branches in patients with and without hypertension or cerebrovascular aneurysms: HTN+, HTN–, AN+ and AN–. A statistically significant decrease was observed for patients with hypertension (*p=0.013) compared with normotensive patients. No significant difference was observed for those with a cerebrovascular aneurysm. Bars indicate 95% confidence intervals. HTN, hypertension; AN, aneurysm; n.s. not significant.

Figure 4

Average number of lenticulostriate artery branches plotted against age. No significant trend was observed.

Figure 5

Illustration of differences in visualised lenticulostriate artery branches between (left) a normotensive patient (60 years old) and (right) a hypertensive patient (61 years old). Large differences were observed in these cases. These images were reconstructed from 0.5-mm original data into a 10-mm coronal slab by using maximum intensity projection.