Expert consensus on neuroimaging diagnosis of dementia and cognitive impairment (2023)

Abstract

For patients with cognitive impairment as the main clinical manifestation, structural MRI (or CT instead) should be performed first to clarify intracranial lesions and brain atrophy. For patients with specific clinical manifestations, specific MRI sequences is recommended to further assist diagnosis. If the patient is suspected of AD, it is recommended to perform oblique coronal T1WI for MTA grading to score medial temporal lobe atrophy. If the patient is suspected to be caused by vascular factors or special infections (prion proteins), it is recommended to perform diffusion-weighted imaging. If the patient has extrapyramidal symptoms or small vessel disease, especially cerebral amyloid angiopathy or cognitive impairment complicated by diabetes, it is recommended to perform susceptibility-weighted imaging. If a mass is suspicious on MRI, contrast-enhanced MR imaging and MR spectroscopy should be performed. If the patient has amyotrophic lateral sclerosis, it is recommended to perform diffusion tensor imaging. If the patient is suspected to be caused by neurodegenerative diseases, it is recommended to perform 18F-FDG PET and Aβ-PET or tau-PET. Aβ-PET imaging and tau-PET imaging can visualize the degree and scope of pathological protein deposition in the brain, which has important predictive and diagnostic value for dementia and can be used for the differential diagnosis of dementia and staging the disease progression. In addition, resting-state functional magnetic resonance imaging, near-infrared spectroscopy, and some emerging imaging techniques such as cine phase-contrast magnetic resonance imaging, and diffusion tensor image analysis along the perivascular space have been studied in patients with cognitive impairment. It is expected that these technologies can be used in the future to better assist the diagnosis and differential diagnosis of cognitive impairment. It should be noted that neuroimaging does not represent the complete diagnosis and clinical symptoms of the disease and must be interpreted with caution.

Keywords

• |dementia|cognitive impairment|alzheimer’s disease|neuroimaging|expert consensus