scholarly journals Synthesis and biological evaluation of novel technetium-99m-labeled phenylquinoxaline derivatives as single photon emission computed tomography imaging probes targeting β-amyloid plaques in Alzheimer's disease

RSC Advances ◽  
2017 ◽  
Vol 7 (33) ◽  
pp. 20582-20590 ◽  
Author(s):  
Shimpei Iikuni ◽  
Masahiro Ono ◽  
Keiichi Tanimura ◽  
Hiroyuki Watanabe ◽  
Masashi Yoshimura ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Single Photon ◽  
Photon Emission ◽  
Biological Evaluation ◽  
Emission Computed Tomography ◽  
Technetium 99M ◽  
Imaging Probes ◽  
Clinical Diagnoses ◽  
Β Amyloid

The development of an imaging probe targeting β-amyloid (Aβ) plaques in Alzheimer's disease labeled with technetium-99m, the most commonly used radioisotope for clinical diagnoses, has been strongly anticipated.

Synthesis and biological evaluation of 123I-labeled pyridyl benzoxazole derivatives: novel β-amyloid imaging probes for single-photon emission computed tomography

RSC Advances ◽  
2015 ◽  
Vol 5 (2) ◽  
pp. 1009-1015 ◽  
Author(s):  
Hiroyuki Watanabe ◽  
Masahiro Ono ◽  
Shimpei Iikuni ◽  
Hiroyuki Kimura ◽  
Yoko Okamoto ◽  
...  
Keyword(s):  
Single Photon ◽  
Photon Emission ◽  
Biological Evaluation ◽  
Emission Computed Tomography ◽  
Single Photon Emission ◽  
Imaging Probes ◽  
Β Amyloid ◽  
Single Photon Emission Computed ◽  
Synthesis And Biological Evaluation ◽  
Photon Emission Computed Tomography

The result in the present study suggested that [123I]9 may be a potential SPECT probe for imaging β-amyloid plaques in the brains of patient with Alzheimer's disease.

scholarly journals Efficacy and Limitations of rCBF-SPECT in the Diagnosis of Alzheimer’s Disease With Amyloid-PET

2019 ◽  
Vol 34 (5) ◽  
pp. 314-321
Author(s):  
Miwako Takahashi ◽  
Tomoko Tada ◽  
Tomomi Nakamura ◽  
Keitaro Koyama ◽  
Toshimitsu Momose
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Rating Scale ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Amyloid Pet ◽  
Clinical Dementia Rating ◽  
Positron Emission ◽  
Rcbf Spect

This study aimed to assess efficacy and limitations of regional cerebral blood flow imaging using single-photon emission computed tomography (rCBF-SPECT) in the diagnosis of Alzheimer’s disease (AD) with amyloid-positron emission tomography (amyloid-PET). Thirteen patients, who underwent both rCBF-SPECT and amyloid-PET after clinical diagnosis of AD or mild cognitive impairment, were retrospectively identified. The rCBF-SPECTs were classified into 4 grades, from typical AD pattern to no AD pattern of hypoperfusion; amyloid-beta (Aβ) positivity was assessed by amyloid-PET. Four patients were categorized into a typical AD pattern on rCBF-SPECT, and all were Aβ+. The other 9 patients did not exhibit a typical AD pattern; however, 4 were Aβ+. The Mini-Mental State Examination score and Clinical Dementia Rating scale were not significantly different between Aβ+ and Aβ– patients. A typical AD pattern on rCBF-SPECT can reflect Aβ+; however, if not, rCBF-SPECT has a limitation to predict amyloid pathology.

Sensitivity, Specificity, and Positive Predictive Value of Technetium 99-HMPAO SPECT in Discriminating Alzheimer's Disease from other Dementias

1997 ◽  
Vol 10 (1) ◽  
pp. 15-21 ◽  
Author(s):  
Donna L. Masterman ◽  
Mario F. Mendez ◽  
Lynn A. Fairbanks ◽  
Jeffrey L. Cummings
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positive Predictive Value ◽  
Predictive Value ◽  
Single Photon ◽  
Photon Emission ◽  
High Sensitivity ◽  
Hmpao Spect ◽  
Clinical Diagnoses ◽  
Sensitivity Specificity

Investigators have reported high sensitivity and specificity values for single photon emission computerized tomography (SPECT) when distinguishing Alzheimer's disease (AD) patients from normal elderly controls or from selected patient groups. The role of SPECT in identifying AD among unselected patients with memory complaints requires investigation. We examined 139 consecutive patients with 99Tc-HMPAO SPECT. NINCDS-ADRDA diagnoses were determined blind to SPECT results, and scans were read and classified by visual inspection blind to clinical diagnoses. Bilateral temporoparietal hypoperfusion (TP) occurred in 75% of probable, 65% of possible, and 45% of unlikely AD patients, yielding a sensitivity of 75% and a specificity of 52% when comparing probable AD versus unlikely AD groups. A positive predictive value of 78% was obtained based on a 69% prevalence of AD in our total clinic population. Patients with false-positive results included a variety of dementing illnesses; all patients with bilateral hypoperfusion had dementia. A pattern of TP on SPECT scans is seen in most patients with AD, but could be found in other dementias as well and cannot be regarded as specific to AD. Reduced TP perfusion discriminated between demented and nondemented individuals. Further strategies for SPECT interpretation that improve diagnostic specificity should be sought.

scholarly journals The Use of [99mTc]-HM-PAO in the Diagnosis of Primary Degenerative Dementia

1988 ◽  
Vol 8 (1_suppl) ◽  
pp. S123-S126 ◽  
Author(s):  
H. J. Testa ◽  
J. S. Snowden ◽  
D. Neary ◽  
R. A. Shields ◽  
A. W. I. Burjan ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Progressive Supranuclear Palsy ◽  
Frontal Lobe ◽  
Single Photon ◽  
Photon Emission ◽  
Cerebral Atrophy ◽  
Emission Computed Tomography ◽  
Clinical Value ◽  
Diagnosis Of Dementia

The clinical value of single photon emission computed tomography (SPECT) in the differential diagnosis of dementia due to cerebral atrophy was evaluated by comparing the pattern of distribution [99mTc]–HM-PAO in three dementing conditions. Imaging was carried out in 26 patients with suspected Alzheimer's disease, 14 with dementia of the frontal-lobe type, and 13 with progressive supranuclear palsy. Images were evaluated and reported without knowledge of clinical diagnosis with respect to regions of reduced uptake of tracer. Reduced uptake in the posterior cerebral hemispheres was characteristic of Alzheimer's disease, while selective anterior hemisphere abnormalities characterized both dementia of the frontal-lobe type and progressive supranuclear palsy. The latter conditions could be distinguished on the basis of the appearance of integrity of the rim of the frontal cortex. The technique has an important role in the differentiation of degenerative dementias.

scholarly journals Case Report: Usefulness of Biomarkers for Alzheimer's Disease in Two Cases With Very-Late-Onset Schizophrenia-Like Psychosis

2021 ◽  
Vol 12 ◽  
Author(s):  
Yuto Satake ◽  
Hideki Kanemoto ◽  
Kenji Yoshiyama ◽  
Ryoko Nakahama ◽  
Keiko Matsunaga ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Psychotic Disorders ◽  
Late Onset ◽  
Single Photon ◽  
Photon Emission ◽  
Brain Magnetic Resonance Imaging ◽  
Later Life ◽  
Emission Computed Tomography ◽  
Amyloid Pet

The association between primary psychotic disorders emerging in later life and neurodegenerative diseases, including Alzheimer's disease (AD), is controversial. We present two female non-demented cases of psychosis with onset above the age of 60 years. Cases 1 and 2 were aged was 68 and 81 years, respectively. They suffered from persecutory delusions and scored 28 on the Mini-Mental State Examination (MMSE) at the first examination. Although detailed neuropsychological tests detected amnesia, they had preserved daily life function. Brain magnetic resonance imaging, N-isopropyl-p-[123I] iodoamphetamine (123I-IMP) single-photon emission computed tomography, and cardiac [123I]-metaiodobenzylguanidine (123I-MIBG) scintigraphy showed no specific abnormalities in either case. We diagnosed them with very-late-onset schizophrenia-like psychosis (VLOSLP) because there was no evidence that their psychoses were derived from organic diseases or affective disorders. Upon close inspection, the AD biomarkers, cerebrospinal fluid (CSF) testing and Florbetapir F 18 positron emission tomography (PET), were positive in Case 1 and negative in Case 2. Case 1 scored 25 1 year later and 23 2 years later on the MMSE and was finally diagnosed as AD dementia. These two cases suggest that some clinically diagnosed VLOSLPs may be a prodromal AD. Although VLOSLP is a disease entity supposed to be a primary psychotic disorder, some are probably secondary psychosis with insidious neurodegeneration. Advanced biomarkers such as amyloid PET and CSF may contribute to the detection of secondary psychosis from clinically diagnosed VLOSLP.

scholarly journals Novel PET/SPECT Probes for Imaging of Tau in Alzheimer’s Disease

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Hiroyuki Watanabe ◽  
Masahiro Ono ◽  
Hideo Saji
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Current State ◽  
Positron Emission ◽  
Number Of Patients ◽  
State Of Research ◽  
Presymptomatic Diagnosis

As the world’s population ages, the number of patients with Alzheimer’s disease (AD) is predicted to increase rapidly. The presence of neurofibrillary tangles (NFTs), composed of hyperphosphorylated tau protein, is one of the neuropathological hallmarks of AD brain. Since the presence of NFTs is well correlated with neurodegeneration and cognitive decline in AD, imaging of tau using positron emission tomography (PET) and single-photon emission computed tomography (SPECT) is useful for presymptomatic diagnosis and monitoring of the progression of AD. Therefore, novel PET/SPECT probes for the imaging of tau have been developed. More recently, several probes were tested clinically and evaluated for their utility. This paper reviews the current state of research on the development and evaluation of PET/SPECT probes for the imaging of tau in AD brain.

Vascular risk factors and the relationships between cognitive impairment and hypoperfusion in late-onset Alzheimer’s disease

2018 ◽  
Vol 30 (6) ◽  
pp. 350-358 ◽  
Author(s):  
Michio Takahashi ◽  
Yasunori Oda ◽  
Koichi Sato ◽  
Yukihiko Shirayama
Keyword(s):  
Diabetes Mellitus ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Late Onset ◽  
Single Photon ◽  
Photon Emission ◽  
Disease Assessment ◽  
Emission Computed Tomography ◽  
Vascular Risk ◽  
Risk Patients

AbstractObjectiveOur recent single-photon emission computed tomography (SPECT) study of patients with late-onset Alzheimer’s disease (AD) revealed that regional cerebral blood flow (rCBF) was reduced in the frontal, temporal, and limbic lobes, and to a lesser degree in the parietal and occipital lobes. Moreover, these patients’ scores on the Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog) were significantly correlated with rCBF in some gyri of the frontal, parietal, and limbic lobes. Our present study aimed to understand how vascular factors and metabolic disease influenced the relationship between rCBF and ADAS-cog scores.MethodsWe divided late-onset AD patients into two groups according to their Hachinski Ischemic Score (HIS), low vascular risk patients had values of ≤4 (n=25) and high vascular risk patients had scores ≥5 (n=15). We examined rCBF using brain perfusion SPECT data.ResultsThe degrees and patterns of reduced rCBF were largely similar between late-onset AD patients in both groups, regardless of HIS values. Cognitive function was significantly associated with rCBF among late-onset AD patients with low vascular risk (HIS≤4), but not among those with high vascular risk (HIS≥5). Furthermore, metabolic diseases, such as hypertension and diabetes mellitus, disrupted the relationships between hypoperfusion and cognitive impairments in late-onset AD patients.ConclusionFactors other than hypoperfusion, such as hypertension and diabetes mellitus, could be involved in the cognitive dysfunction of late-onset AD patients with high vascular risk.

scholarly journals Single Photon Emission Computed Tomography Using 99mTc-HM-PAO in the Routine Evaluation of Alzheimer's Disease

1991 ◽  
Vol 18 (1) ◽  
pp. 59-62 ◽  
Author(s):  
T.A. Hurwitz ◽  
W. Ammann ◽  
D. Chu ◽  
C. Clark ◽  
J. Holden ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Parietal Lobe ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Severe Dementia ◽  
Non Invasive ◽  
The One ◽  
Photon Emission Computed Tomography

ABSTRACT:Regional cerebral blood flow was studied in 7 patients with clinically suspected Alzheimer's disease and 10 normal controls by single photon computed emission tomography (SPECT) using HM-PAO. All patients with Alzheimer's disease and no controls had parietal lobe hypoperfusion which was usually bilateral. In patients with more severe dementia hypoperfusion extended into the frontal lobes. Parietal lobe hypoperfusion corresponds to parietal lobe degeneration which is the one of the first neocortical regions to show the typical degenerative changes of Alzheimer's disease. SPECT with HM-PAO is a non-invasive investigation available in most nuclear medicine departments and complements existing tests in the routine evaluation of patients presenting with dementia.

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