Vertebral artery hypoplasia influences age-related differences in blood flow of the large intracranial arteries

Kathleen B Miller, Samuel J Gallo, Leonardo A Rivera-Rivera, Adam T Corkery, Anna J Howery, Sterling C Johnson, Howard A Rowley, Oliver Wieben, Jill N Barnes, Kathleen B Miller, Samuel J Gallo, Leonardo A Rivera-Rivera, Adam T Corkery, Anna J Howery, Sterling C Johnson, Howard A Rowley, Oliver Wieben, Jill N Barnes

Abstract

Our purpose was to compare cerebral blood flow in the large intracranial vessels between healthy adults with (VAH+) and without (No VAH) vertebral artery hypoplasia. We also evaluated age-related differences in regional blood flow through the large cerebral arteries. Healthy young (n = 20; age = 25 ± 3 years) and older adults (n = 19; age = 61 ± 5 years) underwent 4D flow MRI scans to evaluate blood flow in the internal carotid arteries (ICA) and basilar artery (BA). VAH was determined retrospectively from 4D flow MRI using both structural (vessel diameter ≤ 2 mm) and flow criteria (flow ≤ 50 mL/min). We identified 5 young and 5 older adults with unilateral VAH (prevalence = 26%). ICA flow was lower in the VAH+ group compared with the No VAH group (367 ± 75 mL/min vs. 432 ± 92 mL/min, respectively; p < 0.05). There was no difference in BA flow between VAH+ and No VAH (110 ± 20 mL/min vs. 126 ± 40 mL/min, respectively; p = 0.24). When comparing age-related differences in blood flow in the No VAH group, older adults demonstrated lower BA flow compared with young adults (111 ± 38 mL/min vs. 140 ± 38 mL/min, respectively; p < 0.05) but not ICA flow (428 ± 89 mL/min vs. 436 ± 98 mL/min, respectively; p = 0.82). In contrast, in the VAH+ group, older adults had lower ICA flow compared with young adults (312 ± 65 mL/min vs. 421 ± 35 mL/min, respectively; p < 0.01), but not BA flow (104 ± 16 mL/min vs. 117 ± 23 mL/min, respectively; p = 0.32). Our results suggest that the presence of VAH is associated with lower ICA blood flow. Furthermore, VAH may contribute to the variability in the age-related differences in cerebral blood flow in healthy adults.

Keywords: Aging; Brain blood flow; Cerebral anatomy; Posterior circulation; Stroke risk.

Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

© 2021 The Author(s).

Figures

Fig. 1
Fig. 1
These are example images of the large intracranial arteries from the 4D flow MRI scan. Fig. 1A shows an example of a participant without vertebral artery hypoplasia (No VAH). Fig. 1B shows an example of a participant with VAH on the right side (VAH+). VAH was determined using both structural (hypoplastic vessel diameter less than or equal to 2.0 mm) and flow criteria (hypoplastic vessel flow less than or equal to 50 mL/min). Warmer colors reflect higher blood velocity. BA, basilar artery, L, left, R, right, VA, vertebral artery, VAH, vertebral artery hypoplasia.
Fig. 2
Fig. 2
Blood flow (A, B, C) and pulsatility index (D, E) data from the large intracranial arteries in participants with (VAH+) and without vertebral artery hypoplasia (No VAH) are shown here. A shows global blood flow, B shows internal carotid artery (ICA) blood flow and C shows basilar artery (BA) blood flow. D shows ICA pulsatility index and E shows BA pulsatility index. Bar graphs demonstrate group means ± standard deviation. Group means of No VAH are shown in black and individual data are shown in white circles (n = 29). Group means of VAH+ are shown in white and individual data are shown in white triangles (n = 10). *p 

Fig. 3

Blood flow of the large…

Fig. 3

Blood flow of the large intracranial arteries in young and older participants without…

Fig. 3
Blood flow of the large intracranial arteries in young and older participants without (No VAH; A) and with vertebral artery hypoplasia (VAH+; B) are shown here. In the top panels, group means of young No VAH are shown in grey and individual data is shown in grey circles (n = 15). Group means of older No VAH are shown in white and individual data is shown in white circles (n = 14). In the bottom panels, group means of young VAH+ are shown in grey and individual data is shown in grey triangles (n = 5). Group means of older VAH+ are shown in white and individual data is shown in white triangles (n = 5). BA, basilar artery, ICA, internal carotid arteries. *p 

Fig. 4

Pulsatility index of large intracranial…

Fig. 4

Pulsatility index of large intracranial arteries in young and older participants without (No…

Fig. 4
Pulsatility index of large intracranial arteries in young and older participants without (No VAH; A) and with vertebral artery hypoplasia (VAH+; B) are shown here. In the top panels, group means of young No VAH are shown in grey and individual data is shown in grey circles (n = 15). Group means of older No VAH are shown in white and individual data is shown in white circles (n = 14). In the bottom panels, group means of young VAH+ are shown in grey and individual data is shown in grey triangles (n = 5). Group means of older VAH+ are shown in white and individual data is shown in white triangles (n = 5). BA, basilar artery, ICA, internal carotid arteries. *p 

Supplementary figure 1

Supplementary figure 1

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References
    1. Acar M., Degirmenci B., Yucel A., Albayrak R., Haktanir A., Yaman M. Comparison of vertebral artery velocity and flow volume measurements for diagnosis of vertebrobasilar insufficiency using color duplex sonography. Eur J Radiol Postoperative Knee-Joint. 2005;54:221–224. doi: 10.1016/j.ejrad.2004.06.017. - DOI - PubMed
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Fig. 3
Fig. 3
Blood flow of the large intracranial arteries in young and older participants without (No VAH; A) and with vertebral artery hypoplasia (VAH+; B) are shown here. In the top panels, group means of young No VAH are shown in grey and individual data is shown in grey circles (n = 15). Group means of older No VAH are shown in white and individual data is shown in white circles (n = 14). In the bottom panels, group means of young VAH+ are shown in grey and individual data is shown in grey triangles (n = 5). Group means of older VAH+ are shown in white and individual data is shown in white triangles (n = 5). BA, basilar artery, ICA, internal carotid arteries. *p 

Fig. 4

Pulsatility index of large intracranial…

Fig. 4

Pulsatility index of large intracranial arteries in young and older participants without (No…

Fig. 4
Pulsatility index of large intracranial arteries in young and older participants without (No VAH; A) and with vertebral artery hypoplasia (VAH+; B) are shown here. In the top panels, group means of young No VAH are shown in grey and individual data is shown in grey circles (n = 15). Group means of older No VAH are shown in white and individual data is shown in white circles (n = 14). In the bottom panels, group means of young VAH+ are shown in grey and individual data is shown in grey triangles (n = 5). Group means of older VAH+ are shown in white and individual data is shown in white triangles (n = 5). BA, basilar artery, ICA, internal carotid arteries. *p 

Supplementary figure 1

Supplementary figure 1

Supplementary figure 1
Similar articles
References
    1. Acar M., Degirmenci B., Yucel A., Albayrak R., Haktanir A., Yaman M. Comparison of vertebral artery velocity and flow volume measurements for diagnosis of vertebrobasilar insufficiency using color duplex sonography. Eur J Radiol Postoperative Knee-Joint. 2005;54:221–224. doi: 10.1016/j.ejrad.2004.06.017. - DOI - PubMed
    1. Ainslie P.N., Cotter J.D., George K.P., Lucas S., Murrell C., Shave R., et al. Elevation in cerebral blood flow velocity with aerobic fitness throughout healthy human ageing. J Physiol. 2008;586:4005–4010. doi: 10.1113/jphysiol.2008.158279. - DOI - PMC - PubMed
    1. Albayrak R., Degırmencı B., Acar M., Haktanır A., Colbay M., Yaman M. Doppler sonography evaluation of flow velocity and volume of the extracranial internal carotid and vertebral arteries in healthy adults. J Clin Ultrasound JCU. 2007;35:27–33. doi: 10.1002/jcu.20301. - DOI - PubMed
    1. Bakker S.L.M., de Leeuw F.-E., den Heijer T., Koudstaal P.J., Hofman A., Breteler M.M.B. Cerebral haemodynamics in the elderly: The Rotterdam Study. Neuroepidemiology. 2004;23:178–184. doi: 10.1159/000078503. - DOI - PubMed
    1. Barnes J.N., Schmidt J.E., Nicholson W.T., Joyner M.J. Cyclooxygenase inhibition abolishes age-related differences in cerebral vasodilator responses to hypercapnia. J Appl Physiol. 2012;112:1884–1890. doi: 10.1152/japplphysiol.01270.2011. - DOI - PMC - PubMed
Show all 54 references
Related information
LinkOut - more resources
[x]
Cite
Copy Download .nbib
Format: AMA APA MLA NLM
Fig. 4
Fig. 4
Pulsatility index of large intracranial arteries in young and older participants without (No VAH; A) and with vertebral artery hypoplasia (VAH+; B) are shown here. In the top panels, group means of young No VAH are shown in grey and individual data is shown in grey circles (n = 15). Group means of older No VAH are shown in white and individual data is shown in white circles (n = 14). In the bottom panels, group means of young VAH+ are shown in grey and individual data is shown in grey triangles (n = 5). Group means of older VAH+ are shown in white and individual data is shown in white triangles (n = 5). BA, basilar artery, ICA, internal carotid arteries. *p 

Supplementary figure 1

Supplementary figure 1

Supplementary figure 1
Supplementary figure 1
Supplementary figure 1

References

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