Advantage in Bright-blood and Black-blood Magnetic Resonance Imaging with High-resolution for Analysis of Carotid Atherosclerotic Plaques

Background： About 50% of the cerebral ischemia events are induced by intracranial and extracranial atheroscterosis. This study aimed to evaluate the feasibility and accuracy for displaying atherosclerotic plaques in carotid arteries and analyzing their ingredients by using high-resolution new magnetic resonance imaging （MRI） techniques. Methods： Totally, 49 patients suspected ofextracranial carotid artery stenosis were subjected to cranial MRI scan and magnetic resonance angiography （MRA） examination on carotid arteries, and high-resolution bright-blood and black-blood MRI analysis was carried out within 1 week. Digital subtraction angiography （DSA） examination was carried out for 16 patients within I month. Results： Totally, 103 plaques were detected in the 49 patients, which were characterized by localized or diffusive thickening of the vessel wall, with the intrusion of crescent-shaped abnormal signal into lumens. Fibrous cap was displayed as isointensity in T I -weighted image （T I WI） and hyperintensities in proton density weighted image （PDWI） and T2-weighted image （T2WI）, lipid core was displayed as isointensity or slight hyperintensities in T1WI, isointensity, hyperintensities or hypointensity in PDWI, and hypointensity in T2WI. Calcification in plaques was detected in 11 patients. Eight patients were detected with irregular plaque surface or ulcerative plaques, which were characterized by irregular intravascular space surface in the black-blood sequences, black hypointensity band was not detected in three-dimensional time-of-flight, or the hypointensity band was not continuous, and intrusion of hyperintensities into plaques can be detected. Bright-blood and black-blood techniques were highly correlated with the diagnosis of contrast-enhanced MRA in angiostenosis degree, Rs 0.97, P 〈 0.001. In comparison to DSA, the sensitivity, specificity, and accuracy of MRI diagnosis of stenosis for ≥50% were 88.9%. 100%, and 97.9%, respectively. Conclusions： High-resolution bright-blood and black-blood sequential MRI analysis can accurately analyze ingredients in atherosclerotic plaques, Determined by DSA, MRI diagnosis of stenosis can correctly evaluate the serious degree of arteriostenosis.

Targeted molecular imaging of head and neck squamous cell carcinoma:a window into precision medicine

Tumor biomarkers play important roles in tumor growth,invasion,and metastasis.Imaging of specific biomarkers will help to understand different biological activities,thereby achieving precise medicine for each head and neck squamous cell carcinoma(HNSCC)patient.Here,we describe various molecular targets and molecular imaging modalities for HNSCC imaging.An extensive search was undertaken in the PubMed database with the keywords including"HNSCC,""molecular imaging,""biomarker,"and"multimodal imaging."Imaging targets in HNSCC consist of the epidermal growth factor receptor,cluster of differentiation 44 variant 6(CD44v6),and mesenchymal-epithelial transition factor and integrins.Targeted molecular imaging modalities in HNSCC include optical imaging,ultrasound,magnetic resonance imaging,positron emission tomography,and single-photon emission computed tomography.Making the most of each single imaging method,targeted multimodal imaging has a great potential in the accurate diagnosis and therapy of HNSCC.By visualizing tumor biomarkers at cellular and molecular levels in vivo,targeted molecular imaging can be used to identify specific genetic and metabolic aberrations,thereby accelerating personalized treatment development for HNSCC patients.