Neuroimaging in Dementia: A Brief Review

Abstract

Dementia is a clinical syndrome that manifests itself with impairment in cognitive functions owing to various neurodegenerative etiologies causing severe disability in the older population. Although the diagnosis is largely dependent on clinical examination, biomarkers can significantly aid in early diagnosis of dementia, especially in those without any clinical evidence of neurocognitive impairment. These biomarkers can be discovered in cerebrospinal fluid (CSF) or can be assessed by neuroimaging. Our goal was to discuss and assess the role of different neuroimaging techniques in the early diagnosis of relatively common etiologies of dementia. We used PubMed as search engines to look for helpful articles; most of the sources used were peer reviewed. We discussed the utility of various neuroimaging techniques, such CT, MRI, positron emission tomography (PET) scan, and single-photon emission computed tomography (SPECT), in the diagnosis of dementia. We concluded that various modern neuroimaging techniques prove to be very helpful in early identification, diagnosis, and differentiation between subtypes. However, the actual clinical utility of these tests in terms of their cost-effectivity and availability remains to be seen. Ongoing research is required to further develop biomarkers for early identification and monitor the progression of different etiologies of dementia.

Susceptibility‐Weighted Imaging in Neurodegenerative Disorders: A Review

“…Vascular dementia (as a solitary disease or concurrent with other causes of dementia) is the most common cause of cognitive decline after AD. Vascular dementia often presents with the stepwise cognitive decline with intervening periods of stability and acute deterioration 17 . Cognitive decline of vascular dementia is because of either large vessel strokes, small vessel disease/microangiopathy, and microhemorrhages.…”

“…LBD is one of the α‐synucleinopathies caused by the production and accumulation of abnormal α‐synuclein Lewy bodies in the brainstem, limbic system, and cortical areas. Clinical symptoms of LBD are fluctuating cognition, visual hallucinations, parkinsonism, repeated falls, syncope, transient loss of consciousness, and delusions 17 . Differentiating between LBD and AD can be complicated.…”

“…The pathogenesis in AD is attributed to the accumulation of intracellular amyloid‐beta and the development of extra‐cellular neurofibrillary tangles. The process progresses over the decades before the onset of dementia 17 . Patients with AD have increased prevalence rates of microhemorrhages compared to healthy controls and those with subjective cognitive impairment.…”

Neuroimaging in Dementia With Lewy Bodies

“…Hence, the most crucial hurdle to overcome in the management of DLB lies in making an early diagnosis and accurately ruling out other possible differentials [5]. Biomarkers are defined as substances in the body that can be objectively measured and able to signify an underlying disease process, preferably at an early stage of the disease [6]. Neuroimaging plays an integral role in the identification of these biomarkers and in this article, we aim to provide a brief review of imaging modalities contributing towards early diagnosis of DLB.…”

The Role of 18F-Flortaucipir (AV-1451) in the Diagnosis of Neurodegenerative Disorders

“…This is followed by vascular dementia (VaD), which is considered the second most common cause of dementia [ 4 ]. Other causes of dementia include frontotemporal dementia (FTD), dementia with Lewy bodies (DLB), Parkinson’s disease with dementia (PDD) [ 5 , 6 ]. In both the central and peripheral nervous system, microtubule assembly (MT) is promoted by a microtubule assembly protein (MAP), also known as Tau protein.…”