Density Assessment of Intracranial Arteriosclerosis via CT Imaging in a Population Cohort

Overview

This study evaluated intracranial artery calcification (IAC) density using non-contrast MDCT imaging in a large population-based cohort. It identified key determinants of IAC density and explored differences between medial and intimal calcification subtypes, providing novel insights into intracranial arteriosclerosis characteristics.

Background

Intracranial artery calcification (IAC) is a hallmark of intracranial arteriosclerosis and a known risk factor for stroke and dementia. Prior research has focused primarily on the prevalence and volume of IAC, while the density of calcifications—an important factor in coronary artery disease—remains understudied in intracranial vessels. Distinct morphological subtypes of IAC, medial and intimal, differ in their clinical associations and may also differ in calcification density, which could improve subtype differentiation and risk stratification.

Data Highlights

A total of 2464 participants aged ≥55 years from the Rotterdam Study underwent non-contrast-enhanced MDCT imaging to assess intracranial artery calcification density. Imaging was performed using 16-slice or 64-slice scanners optimized for intracranial arteries. Cardiovascular risk factors and medical history were comprehensively collected through interviews, physical exams, and medical registries. The IAC assessment method demonstrated excellent inter-rater reliability with an intraclass correlation coefficient of 0.99.

Key Findings

• IAC density was quantified in a large, population-based cohort using non-contrast MDCT imaging, enabling detection of low-density calcifications.
• Distinct morphological subtypes of IAC—medial and intimal—have differing clinical associations and potentially different calcification densities.
• Medial subtype calcifications are linked to diabetes, vascular disease, and worse outcomes in stroke, whereas intimal subtype is associated with smoking, hypertension, and better collateral status.
• Cardiovascular risk factors were systematically evaluated to determine their influence on IAC density.
• The study methodology for IAC density assessment is validated and highly reproducible, supporting its use in future research and clinical settings.

Clinical Implications

Assessing IAC density provides additional information beyond calcification volume and may improve differentiation between medial and intimal calcification subtypes. This could enhance risk stratification for stroke and dementia in clinical practice. Non-contrast MDCT imaging is a feasible and reliable method for evaluating IAC density in older adults, facilitating broader implementation in population screening and research.

Conclusion

This population-based study advances understanding of intracranial arteriosclerosis by characterizing IAC density and its determinants. The findings support the potential clinical value of incorporating calcification density assessment into cerebrovascular risk evaluation.

References

1. Rotterdam Study Group/2000 -- Population-based cohort study design
2. Various Authors/2000-2020 -- Intracranial artery calcification and stroke/dementia risk
3. Coronary Artery Calcification Research/2010-2015 -- Density as marker of plaque stability
4. Imaging Methodology Validation Studies/2010-2020 -- IAC assessment reliability