Histology-Verified Intracranial Artery Calcification and Its Clinical Relevance With Cerebrovascular Disease

Abstract

Intracranial artery calcification (IAC) was regarded as a proxy for intracranial atherosclerosis (ICAS). IAC could be easily detected on routine computer tomography (CT), which was neglected by clinicians in the previous years. The evolution of advanced imaging technologies, especially vessel wall scanning using high resolution-magnetic resonance imaging (HR-MRI), has aroused the interest of researchers to further explore the characteristics and clinical impacts of IAC. Recent histological evidence acquired from the human cerebral artery specimens demonstrated that IAC could mainly involve two layers: the intima and the media. Accumulating evidence from histological and clinical imaging studies verified that intimal calcification is more associated with ICAS, while medial calcification, especially the internal elastic lamina, contributes to arterial stiffness rather than ICAS. Considering the highly improved abilities of novel imaging technologies in differentiating intimal and medial calcification within the large intracranial arteries, this review aimed to describe the histological and imaging features of two types of IAC, as well as the risk factors, the hemodynamic influences, and other clinical impacts of IAC occurring in intimal or media layers.

Intracranial carotid artery calcification morphology differs in patients with lacunar and nonlacunar acute ischemic strokes

“…Two distinct subtypes of ICAC have been recognized, involving respectively the intimal and medial layers of the arterial wall, with different underlying mechanisms and risk factors [5]. Intimal calcifications are linked to atherosclerotic disease, whereas medial calcifications are thought to originate from an atherosclerosis‐independent process [6, 7]. Recently, a computed tomography (CT)‐based score has been validated to distinguish ICAC subtype in vivo, allowing investigation of their clinical significance [8], which is still unclear [6]; the association of ICAC patterns and stroke subtypes also remains unclear.…”

Intracranial Artery Calcifications Profile as a Predictor of Recanalization Failure in Endovascular Stroke Treatment

“…15 No significant correlation between medial calcification and luminal stenosis has been established yet, although it is thought to affect arterial stiffening with consequent compliance deterioration and vasodilation limitation. 16,17 Furthermore, EVT in acute ischemic stroke with underlying intracranial atherosclerotic disease has been described as more complex and technically challenging, with a higher probability of recanalization failure. 18,19 Thus, the presence of intimal IAC on imaging can be considered as an adjunct biomarker in the diagnosis of intracranial atherosclerotic disease in addition to other imaging biomarkers and modalities such as the presence intracranial plaque and perfusion imaging.…”

Detecting vulnerable carotid plaque and its component characteristics: Progress in related imaging techniques

“…High-resolution magnetic resonance imaging (HRMRI) is currently considered the most competitive imaging method for examining the carotid artery wall due to an extremely high soft-tissue resolution ( 20 ). With the application of 3.0T high-field magnetic resonance instruments and the maturation of black-blood technology and multi-contrast sequence imaging technology, MRI offers further advantages to other imaging methods, providing greater aid for identifying plaque internal components and evaluation of plaque stability.…”