Identification of high-risk plaque features in intracranial atherosclerosis: initial experience using a radiomic approach

Eur Radiol. 2018 Sep;28(9):3912-3921. doi: 10.1007/s00330-018-5395-1. Epub 2018 Apr 9.

Abstract

Objectives: To evaluate a quantitative radiomic approach based on high-resolution magnetic resonance imaging (HR-MRI) to differentiate acute/sub-acute symptomatic basilar artery plaque from asymptomatic plaque.

Methods: Ninety-six patients with basilar artery stenosis underwent HR-MRI between January 2014 and December 2016. Patients were scanned with T1- and T2-weighted imaging, as well as T1 imaging following gadolinium-contrast injection (CE-T1). The stenosis value, plaque area/burden, lumen area, minimal luminal area (MLA), intraplaque haemorrhage (IPH), contrast enhancement ratio and 94 quantitative radiomic features were extracted and compared between acute/sub-acute and asymptomatic patients. Multi-variate logistic analysis and a random forest model were used to evaluate the diagnostic performance.

Results: IPH, MLA and enhancement ratio were independently associated with acute/subacute symptoms. Radiomic features in T1 and CE-T1 images were associated with acute/subacute symptoms, but the features from T2 images were not. The combined IPH, MLA and enhancement ratio had an area under the curve (AUC) of 0.833 for identifying acute/sub-acute symptomatic plaques, and the combined T1 and CE-T1 radiomic approach had a significantly higher AUC of 0.936 (p = 0.01). Combining all features achieved an AUC of 0.974 and accuracy of 90.5%.

Conclusions: Radiomic analysis of plaque texture on HR-MRI accurately distinguished between acutely symptomatic and asymptomatic basilar plaques.

Key points: • High-resolution magnetic resonance imaging can assess basilar artery atherosclerotic plaque. • Radiomic features in T1 and CE-T1 images are associated with acute symptoms. • Radiomic analysis can accurately distinguish between acute symptomatic and asymptomatic plaque. • The highest accuracy may be achieved by combining radiomic and conventional features.

Keywords: Atherosclerotic plaques; Basilar artery; Intracranial arteriosclerosis; Magnetic resonance imaging; Stroke.

MeSH terms

  • Aged
  • Basilar Artery / diagnostic imaging*
  • Basilar Artery / pathology*
  • Contrast Media
  • Female
  • Gadolinium
  • Humans
  • Intracranial Arteriosclerosis / diagnostic imaging*
  • Intracranial Arteriosclerosis / pathology*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Plaque, Atherosclerotic / diagnostic imaging*
  • Plaque, Atherosclerotic / pathology*

Substances

  • Contrast Media
  • Gadolinium