Biodistribution, toxicity and radiation dosimetry studies of the serotonin transporter radioligand 4-[18F]-ADAM in rats and monkeys

Purpose  

4-[¹⁸F]-ADAM is a potent serotonin transport imaging agent. We studied its toxicity in rats and radiation dosimetry in monkeys before human studies are undertaken.     

Synthesis and biological evaluation of [18F]tetrafluoroborate: a PET imaging agent for thyroid disease and reporter gene imaging of the sodium/iodide symporter

Purpose

The human sodium/iodide symporter (hNIS) is a well-established target in thyroid disease and reporter gene imaging using gamma emitters ¹²³I-iodide, ¹³¹I-iodide and ^99mTc-pertechnetate. However, no PET imaging agent is routinely available. The aim of this study was to prepare and evaluate ¹⁸F-labelled tetrafluoroborate ([¹⁸F]TFB) for PET imaging of hNIS.

Methods

[¹⁸F]TFB was prepared by isotopic exchange of BF ₄ ^? with [¹⁸F]fluoride in hot hydrochloric acid and purified using an alumina column. Its identity, purity and stability in serum were determined by HPLC, thin-layer chromatography (TLC) and mass spectrometry. Its interaction with NIS was assessed in vitro using FRTL-5 rat thyroid cells, with and without stimulation by thyroid-stimulating hormone (TSH), in the presence and absence of perchlorate. Biodistribution and PET imaging studies were performed using BALB/c mice, with and without perchlorate inhibition.

Results

[¹⁸F]TFB was readily prepared with specific activity of 10 GBq/mg. It showed rapid accumulation in FRTL-5 cells that was stimulated by TSH and inhibited by perchlorate, and rapid specific accumulation in vivo in thyroid (SUV?=?72 after 1 h) and stomach that was inhibited 95% by perchlorate.

Conclusion

[¹⁸F]TFB is an easily prepared PET imaging agent for rodent NIS and should be evaluated for hNIS PET imaging in humans.     

Preclinical characterization of <Superscript>18</Superscript>F-D-FPHCys,a new amino acid-based PET tracer

Purpose  

The imaging potential of a new ¹⁸F-labelled methionine derivative, S-(3-[¹⁸F]fluoropropyl)-d-homocysteine (¹⁸F-D-FPHCys), and its selectivity for amino acid transporter subtypes were investigated in vitro and by imaging of human tumour xenografts.     

Impact of carbohydrate restriction with and without fatty acid loading on myocardial <Superscript>18</Superscript>F-FDG uptake during PET: A randomized controlled trial

Background  

Low-carbohydrate (LC) and high-fat, low-carbohydrate (HFLC) dietary preparations may enhance ¹⁸F-FDG-PET-based imaging of small, inflamed structures near the heart by suppressing myocardial FDG signal. We compared myocardial ¹⁸F-FDG uptake in patients randomized to LC, HFLC, and unrestricted (UR) preparations prior to ¹⁸F-FDG-PET.     

Clearance of the high intestinal 18F-FDG uptake associated with metformin after stopping the drug

Purpose  

This study was done to determine whether interruption of metformin before ¹⁸F-FDG PET/CT imaging could prevent the increased ¹⁸F-FDG uptake in the intestine caused by this drug.     

Therapeutic impact of [18F]fluoride positron-emission tomography/computed tomography on patients with unclear foot pain

Purpose  

To evaluate the therapeutic impact of [¹⁸F]fluoride positron-emission tomography/computed tomography ([¹⁸F]fluoride PET/CT) imaging on patients with unclear foot pain.     

PET imaging of inflammation and adenocarcinoma xenografts using vascular adhesion protein 1 targeting peptide 68Ga-DOTAVAP-P1: comparison with 18F-FDG

Purpose  

The aim of this study was to evaluate inflammation and tumour imaging with a vascular adhesion protein 1 (VAP-1) targeting peptide ⁶⁸Ga-DOTAVAP-P1 in comparison with ¹⁸F-FDG.     

<Superscript>123</Superscript>I-MIBG scintigraphy/SPECT versus <Superscript>18</Superscript>F-FDG PET in paediatric neuroblastoma

Purpose  

To analyse different uptake patterns in ¹²³I-MIBG scintigraphy/SPECT imaging and ¹⁸F-FDG PET in paediatric neuroblastoma patients.     

Technetium 94m-labeled methoxyisobutyl isonitrile: Dosimetry and resting cardiac imaging with positron emission tomography

Background  

Development of a positronemitting form of technetium has allowed the imaging of technetium radiopharmaceuticals with positron emission tomography (PET). We used^94mTc to compare the distribution of the myocardial perfusion agent sestamibi at rest with the conventional PET perfusion tracer¹³N-labeled ammonia (¹³N-ammonia).     

An efficient and aseptic preparation of “sodium fluoride (<Superscript>18</Superscript>F) injection” in a GMP compliant facility

Introduction  

“Sodium fluoride (¹⁸F) injection” is an isotonic NaCl solution containing [¹⁸F]NaF to be used as bone imaging agent. Although its NDA was approved by the US FDA in 1972, it has not been commercially available since 1975 due to mostly the popularity of ^99mTc-MDP. Recently, advances in PET/CT technology and the often interrupted ^99mTc supply have led to the renewed interest in the use of [¹⁸F]NaF to detect bone metastases in cancer patients. This report introduces an efficient, low-cost and aseptic preparation of “Sodium fluoride (¹⁸F) injection” for PET scan.     

PET with 18F-labelled choline-based tracers for tumour imaging: a review of the literature

Purpose  

To give an up-to-date overview of the potential clinical utility of ¹⁸F-labelled choline derivatives for tumour imaging with positron emission tomography.     

Comparison of diffusion-weighted MR imaging and FDG PET/CT to predict pathological complete response to neoadjuvant chemotherapy in patients with breast cancer

Objective  

To compare the use of diffusion-weighted MR imaging (DWI) and ¹⁸F-FDG PET/CT to predict pathological complete response (pCR) in breast cancer patients receiving neoadjuvant chemotherapy.     

99mTc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

Purpose  

^99mTc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine ^99mTc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury.     

Preoperative [18F]FDG PET/CT maximum standardized uptake value predicts recurrence of uterine cervical cancer

Purpose  

To determine if preoperative [¹⁸F]FDG-PET/CT imaging has prognostic significance in patients with uterine cervical cancer.     

Image-derived input function in dynamic human PET/CT: methodology and validation with 11C-acetate and 18F-fluorothioheptadecanoic acid in muscle and 18F-fluorodeoxyglucose in brain

Purpose  

Despite current advances in PET/CT systems, blood sampling still remains the standard method to obtain the radiotracer input function for tracer kinetic modelling. The purpose of this study was to validate the use of image-derived input functions (IDIF) of the carotid and femoral arteries to measure the arterial input function (AIF) in PET imaging. The data were obtained from two different research studies, one using ¹⁸F-FDG for brain imaging and the other using ¹¹C-acetate and ¹⁸F-fluoro-6-thioheptadecanoic acid (¹⁸F-FTHA) in femoral muscles.     

<Superscript>18</Superscript>F-FDG PET response to neoadjuvant chemotherapy for Ewing sarcoma and osteosarcoma are different

Objective  

Ewing sarcoma (ES) and osteosarcoma (OS) have different biological characteristics and respond differently to chemotherapy. We reviewed ¹⁸F-FDG PET imaging characteristics of ES and OS patients at baseline and following treatment to determine whether this biological variation is reflected in their imaging phenotype.     

Feasibility and kinetic characteristics of 68Ga-NOTA-RGD PET for in vivo atherosclerosis imaging

Objective

In this study, the feasibility and kinetic characteristics of the ⁶⁸Ga-NOTA-RGD, a recently developed RGD peptide agent, were investigated for atherosclerosis imaging in comparison with ¹⁸FDG.

Methods

ApoE^?/? mice were fed a high-fat diet for more than 20 weeks. To evaluate the feasibility, tissue uptakes of ⁶⁸Ga-NOTA-RGD and ¹⁸FDG in the major organs were measured and compared between ApoE^?/? and control mice. Animal PET imaging was also performed and relative uptake values in the thoracic aorta were compared between ApoE^?/? and control mice. In humans, the kinetic characteristics and feasibility of ⁶⁸Ga-NOTA-RGD PET were assessed in 4 patients with known coronary artery disease.

Results

In the tissue uptake study, the thoracic aorta showed higher uptake in ApoE^?/? than in control mice with both ⁶⁸Ga-NOTA-RGD and ¹⁸FDG (P < 0.001). On PET scans, the relative uptake values of the thoracic aorta were significantly higher in ApoE^?/? with both ⁶⁸Ga-NOTA-RGD (P = 0.024) and ¹⁸FDG (P = 0.038). In human PET, the appropriateness of reversible binding model and Logan plotting was clearly demonstrated. The aorta-to-jugular ratios were measured up to 1.25 and showed a tendency to correlate with the serum high-sensitivity C-reactive protein level (r = 0.899, P = 0.102).

Conclusions

⁶⁸Ga-NOTA-RGD has potential as an in vivo atherosclerosis imaging agent. However, the lower imaging contrast and sensitivity of ⁶⁸Ga-NOTA-RGD PET compared with ¹⁸FDG PET may be a limitation for clinical application.     

Cardiac imaging and safety evaluation of BMS747158, a novel PET myocardial perfusion imaging agent,in chronic myocardial compromised rabbits

Background  

BMS747158 labeled with ¹⁸F is being developed for PET myocardial perfusion imaging. Imaging studies showed clear detection of necrotic tissue in acute myocardial infarcted (MI) animals and a good safety profile in normal animals. This study evaluated BMS747158 imaging and cardiovascular safety in a rabbit model of chronic MI with cardiac compromise.     

FDG PET/CT and diffusion-weighted imaging for breast cancer: prognostic value of maximum standardized uptake values and apparent diffusion coefficient values of the primary lesion

Purpose  

To correlate both primary lesion ¹⁸F-fluorodeoxyglucose (FDG) maximum standardized uptake value (SUVmax) and diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) with clinicopathological prognostic factors and compare the prognostic value of these indexes in breast cancer.     

A method of adjusting SUV for injection-acquisition time differences in 18 F-FDG PET Imaging

Objective  

A time normalisation method of tumour SUVs in ¹⁸ F-FDG PET imaging is proposed that has been verified in lung cancer patients.