Dosimetry and efficacy of a tau PET tracer [F]MK-6240 in Japanese healthy elderly and patients with Alzheimer's disease.

Objective: A new tau PET tracer [F]MK-6240 has been developed; however, its dosimetry and pharmacokinetics have been published only for a European population. This study investigated the safety, radiation dosimetry, pharmacokinetics and biodistribution of [F]MK-6240 in Japanese elderly subjects. Also, the pattern and extent of brain retention of [F]MK-6240 in Japanese healthy elderly subjects and patients with Alzheimer's disease (AD) were investigated.

PET imaging of C-labeled thiamine tetrahydrofurfuryl disulfide, vitamin B derivative: First-in-human study.

Unlabelled: Vitamine B thiamine is an essential component for glucose metabolism and energy production. The disulfide derivative, thiamine tetrahydrofurfuryl disulfide (TTFD), is more absorbent compared to readily-available water-soluble thiamine salts since it does not require the rate-limiting transport system required for thiamine absorption. However, the detailed pharmacokinetics of thiamine and TTFD under normal and pathological conditions were not clarified yet.

Physiological skin FDG uptake: A quantitative and regional distribution assessment using PET/MRI.

Purpose: To retrospectively assess the repeatability of physiological F-18 labeled fluorodeoxyglucose (FDG) uptake in the skin on positron emission tomography/magnetic resonance imaging (PET/MRI) and explore its regional distribution and relationship with sex and age.

Methods: Out of 562 examinations with normal FDG distribution on whole-body PET/MRI, 74 repeated examinations were evaluated to assess the repeatability and regional distribution of physiological skin uptake. Furthermore, 224 examinations were evaluated to compare differences in the uptake due to sex and age.

Quantitative investigation of hepatobiliary transport of [C]telmisartan in humans by PET imaging.

The pharmacokinetics of telmisartan are nonlinear within the clinical dose range. To identify the underlying mechanism of this nonlinearity, we conducted a PET study in healthy subjects using [C]telmisartan. Eight healthy male subjects were enrolled in a 2-way crossover study.

Voxel-based statistical analysis and quantification of amyloid PET in the Japanese Alzheimer's disease neuroimaging initiative (J-ADNI) multi-center study.

Background: Amyloid PET plays a vital role in detecting the accumulation of in vivo amyloid-β (Aβ). The quantification of Aβ accumulation has been widely performed using the region of interest (ROI)-based mean cortical standardized uptake value ratio (mcSUVR). However, voxel-based statistical analysis has not been well studied.

[Technical Considerations on Scanning and Image Analysis for Amyloid PET in Dementia].

Brain imaging techniques, such as computed tomography (CT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and positron emission tomography (PET), can provide essential and objective information for the early and differential diagnosis of dementia. Amyloid PET is especially useful to evaluate the amyloid-β pathological process as a biomarker of Alzheimer's disease. This article reviews critical points about technical considerations on the scanning and image analysis methods for amyloid PET.

A revisit to quantitative PET with F-FDOPA of high specific activity using a high-resolution condition in view of application to regenerative therapy.

Objective: With the advent of regenerative/cell therapy for Parkinson's disease (PD), F-FDOPA has drawn new attention as a biomarker of the therapeutic that cannot be evaluated with radiopharmaceuticals for dopamine transporter. Since most previous F-FDOPA PET studies were carried out many years ago with a PET scanner of lower resolution and with F-FDOPA of low specific activity synthesized from F-F, we used a newer PET/CT scanner with a high-resolution condition and F-FDOPA synthesized from F-F to re-evaluate this technique on normal subjects and patients with PD, together with D receptor imaging with C-raclopride (RAC).

Methods: PET scans were carried out with F-FDOPA for 120 min and with C-RAC for 60 min on 10 patients clinically diagnosed with PD and on 10 normal control subjects.

Exploratory human PET study of the effectiveness of (11)C-ketoprofen methyl ester, a potential biomarker of neuroinflammatory processes in Alzheimer's disease.

Introduction: Neuroinflammatory processes play an important role in the pathogenesis of Alzheimer's disease (AD). As a biomarker of neuroinflammatory processes, we designed (11)C-labeled ketoprofen methyl ester ([(11)C]KTP-Me) to increase the blood-brain barrier permeability of ketoprofen (KTP), a selective cyclooxygenase-1 (COX-1) inhibitor. Animal studies indicated that [(11)C]KTP-Me enters the brain and accumulates in activated microglia of inflammatory lesions.

[Harmonization of Standardized Uptake Value among Different Generation PET/ CT Cameras Based on a Phantom Experiment -Utility of SUV(peak)].

Standardized uptake value (SUV) has been widely used as a semi-quantitative metric of uptake in FDGPET/ CT for diagnosis of malignant tumors and evaluation of tumor therapies. However, the SUV depends on various factors including PET/CT scanner specifications and reconstruction parameters. The purpose of this study is to harmonize the SUV among two PET/CT models of different generation: two units of Discovery ST Elite Performance(DSTEP) and Discovery 690 (D690) PET/CT scanners.

Optimization of image reconstruction conditions with phantoms for brain FDG and amyloid PET imaging.

Objectives: The purpose of this study was to optimize image reconstruction conditions for brain (18)F-FDG, (11)C-PiB, (18)F-florbetapir and (18)F-flutemetamol PET imaging with Discovery-690 PET/CT for diagnosis and research on Alzheimer's disease (AD) based on the standard imaging protocols and phantom test procedures and criteria published by the Japanese society of nuclear medicine (JSNM).

Methods: A Hoffman 3D brain phantom and a cylindrical pool phantom were scanned according to the JSNM procedure, and the reconstruction conditions (iteration, subset, post-filter) were optimized so that the images satisfy the JSNM criteria regarding spatial resolution (FWHM ≤ 8 mm) and gray/white matter contrast (%contrast ≥ 55%) on the Hoffman phantom and uniformity (SD of small ROIs ≤ 0.0249) and image noise (coefficient of variation ≤ 15 %) on the pool phantom.

Influence of Statistical Fluctuation on Reproducibility and Accuracy of SUVmax and SUVpeak: A Phantom Study.

Unlabelled: Standardized uptake values (SUVs) have been widely used in the diagnosis of malignant tumors and in clinical trials of tumor therapies as semiquantitative metrics of tumor (18)F-FDG uptake. However, SUVs for small lesions are liable to errors due to partial-volume effect and statistical noise. The purpose of this study was to evaluate the reproducibility and accuracy of maximum and peak SUV (SUVmax and SUVpeak, respectively) of small lesions in phantom experiments.

Human whole-body biodistribution and dosimetry of a new PET tracer, [(11)C]ketoprofen methyl ester, for imagings of neuroinflammation.

Introduction: Neuroinflammatory processes play an important role in the pathogenesis of Alzheimer's disease and other brain disorders, and nonsteroidal anti-inflammatory drugs (NSAIDs) are considered therapeutic candidates. As a biomarker of neuroinflammatory processes, (11)C-labeled ketoprofen methyl ester ([(11)C]KTP-Me) was designed to allow cerebral penetration of ketoprofen (KTP), an active form of a selective cyclooxygenase-1 inhibitor that acts as an NSAID. Rat neuroinflammation models indicate that [(11)C]KTP-Me enters the brain and is retained in inflammatory lesions, accumulating in activated microglia.