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Lesions of the deep digital flexor tendon (DDFT) are a cause for foot lameness in horses. Positron emission tomography (PET) could provide valuable information regarding the metabolic activity of these lesions. The aims of this exploratory, prospective, methods comparison study were to assess the ability of 18 fluorine-fluorodeoxyglucose (18 F-FDG) PET to detect DDFT lesions and to compare the PET findings with CT and MRI findings. Eight horses with lameness due to pain localized to the front feet were included. Both front limbs of all horses were imaged with 18 F-FDG PET, noncontrast CT, and arterial contrast-enhanced CT; 11 limbs were also assessed using MRI. Two observers graded independently 18 F-FDG PET, noncontrast CT, arterial contrast CT, T1-weighted (T1-w) MRI, and T2-weighted (T2-w)/STIR MRI. Maximal standardized uptake values were measured. Lesions were found in seven of 16 DDFT on PET, 12 of 16 DDFT on noncontrast CT, six of 15 DDFT on arterial contrast CT, eight of 11 DDFT on T1-w MRI, and six of 11 DDFT on T2-w/STIR MRI. Positron emission tomography was in better agreement with arterial contrast CT (Kappa-weighted 0.40) and T2-w/STIR MRI (0.35) than with noncontrast CT (0.28) and T1-w MRI (0.20). Maximal standardized uptake values of lesions ranged from 1.9 to 4.6 with a median of 3.1. Chronic lesions with scar tissues identified on noncontrast CT or T1-w MRI did not have increased 18 F-FDG uptake. These results demonstrated that 18 F-FDG PET agreed more closely with modalities previously used to detect active tendon lesions, i.e. arterial contrast CT and T2-w/STIR MRI. 18 Fluorine-fluorodeoxyglucose PET can be used to identify metabolically active DDFT lesions in horses.

Objectives The aim of the study was to evaluate the utility of 18fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in the diagnosis, staging, restaging, and treatment response of childhood malignancies. Methods This study included 52 patients (32 boys, 20 girls) who were referred to our clinic between November 2008 and December 2018 with the diagnosis of malignancy. The patients were evaluated retrospectively. Median age of the patients was 13 years (range 2-17). 18F-FDG was given to the patients intravenously, and time of flight with PET/16 slice CT was performed 1 hour thereafter. The lowest dose was 2 mCi (74 MBq) and the highest dose was 10 mCi (370 MBq). Fasting blood sugars of all patients were found below 200 mg/dL (11.1 mmol/L). Results 18F-FDG PET/CT was performed to evaluate the response to treatment in 38 of 52 children, staging in 11 patients (staging and evaluation of the response to treatment in nine of them), restaging in 2 patients, restaging, and evaluation of the response to treatment in 1 patient. 18F-FDG PET/CT examination was reported as normal in 13 patients (5 girls, 8 boys). The pathological 18F-FDG uptake was detected in 39 patients (14 girls, 25 boys), which indicated metastasis and/or recurrence of the primary disease. Total number of deaths was 30 (13 girls, 17 boys). Conclusion 18F-FDG PET/CT has a significant role for staging, restaging, treatment response, and detection of metastatic disease but it is limited for the early diagnosis of childhood cancers.

Background Neoadjuvant chemotherapy (NAC) is a therapeutic option for locally advanced breast cancer and is aiming to reduce tumor volume for breast conservation. Accurate assessment of residual tumor after NAC is a crucial for determining the outcome and survival of the patients. Eighteen fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has been recently used as a reliable tool to evaluate response to treatment due to combined morphologic and metabolic information. The aim of this study was to assess the value of 18F-FDG PET/CT in evaluation of response to NAC in a sample size of recently diagnosed 30 locally advanced breast cancer patients, who were referred for 18F-FDG PET/CT scanning before and after NAC. The morphologic and metabolic response was evaluated and compared to histopathologic findings. Results 18F-FDG PET/CT detected 23 responders and 7 non-responders among the examined 30 breast cancer patients, compared to 20 responders and 10 non-responders detected by CT alone. 18F-FDG PET/CT showed sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 95.5%, 75%, 91.3, 85.7, and 90%, respectively, compared to 81.8%, 75%, 90, 60, and 80%, respectively, achieved by CT alone. Conclusion 18F-FDG PET/CT is a reliable single whole body imaging tool which can be used in monitoring of NAC response in patients with locally advanced breast cancer showing higher sensitivity and accuracy compared to CT alone.

Substituted indoles can be prepared from phenylazocarboxylates through a rapid one-pot sequence featuring a microwave-assisted Fischer indole synthesis as a key step. Considering that the phenylazocarboxylates may beforehand be modified by mild nucleophilic aromatic substitution, including the introduction of [18 F]fluoride, the overall strategy offers an attractive new access to 5-[18 F]fluoroindoles.

Background: Kidneys and urinary bladder are common physiologic uptake sites of 18fluorinefluorodeoxyglucose ( 18 F-FDG) causing increased exposure of low energy ionizing radiation to these organs. Accurate measurement of organ dose is vital as 18 F-FDG is directly exposed to the organs. Organ dose from 18 F-FDG PET is calculated according to the injected 18 F-FDG activity with the application of dose coefficients established by International Commission on Radiological Protection (ICRP). But this dose calculation technique is not directly measured from these organs; rather it is calculated based on total injected activity of radiotracer prior to scanning. This study estimated the 18 F-FDG dose to the kidneys and urinary bladder in whole body positron emission tomography/computed tomography (PET/CT) examination by comparing dose from total injected activity of 18 F-FDG (calculated dose) and dose from organs activity based on the region of interest (ROI) (measured dose). Methods: Nine subjects were injected intravenously with the mean 18 F-FDG dose of 292.42 MBq prior to whole body PET/CT scanning. Kidneys and urinary bladder doses were estimated by using two approaches which are the total injected activity of 18 F-FDG and organs activity concentration of 18 F-FDG based on drawn ROI with the application of recommended dose coefficients for 18 F-FDG described in the ICRP 80 and ICRP 106. Results: The mean percentage difference between calculated dose and measured dose ranged from 98.95% to 99.29% for the kidneys based on ICRP 80 and 98.96% to 99.32% based on ICRP 106. Whilst, the mean percentage difference between calculated dose and measured dose was 97.08% and 97.27% for urinary bladder based on ICRP 80 while 96.99% and 97.28% based on ICRP 106. Whereas, the range of mean percentage difference between calculated and measured organ doses derived from ICRP 106 and ICRP 80 for kidney doses were from 17.00% to 40.00% and for urinary bladder dose was 18.46% to 18.75%. Conclusions: There is a significant difference between calculated dose and measured dose. The use of organ activity estimation based on drawn ROI and the latest version of ICRP 106 dose coefficient should be explored deeper to obtain accurate radiation dose to patients.

Aims: To investigate the effect of delayed imaging protocol and hypoglycemic agent on quantitative values obtained during myocardial viability

Hot lab dispensing of large doses of 18 fluorine fluorodeoxyglucose in master vials supplied from the cyclotrons requires high degrees of skill to handle high doses. Presently practiced conventional method of fractionating from the inverted tiltable vial pig mounted on a metal frame has its own limitations such as increasing isotope handling times and exposure to the technologist. Innovative technique devised markedly improves the fractionating efficiency along with speed, precision, and reduced dose exposure.

The detection and staging of many cancers is rapidly becoming dependent on positron emission tomography (PET) with the glucose analog 18 fluorine fluorodeoxyglucose (FDG). FDG demonstrates increased uptake in a majority of malignant lesions as well as an increasing number of benign conditions that can be confused with a malignant neoplasm. Osseous injury associated with anterior cruciate ligament (ACL) and meniscal tears have been detected with bone scanning agents.

Positron emission tomography computed tomography (PET-CT) is a combined functional and structural multi modality imaging tool that can be utilized to detect vulnerable and atherosclerotic plaques. In this study we observe the prevalence of active and calcified plaques in selected arteries during whole-body 18F-FDG PET-CT and correlate the findings with risk factors in developing coronary artery disease. There was a significant relationship between patients with high body mass index and vulnerable plaques. We concluded that 18F-FDG PET-CT can be utilized in detecting focal high FDG uptake within vascular plaque in early recognition of high risk patients having vascular accidents.Keywords: Atherosclerosis; Plaque; Computed tomography; Positron emission tomography; Fluorodeoxyglucose; Multimodality

Purpose: The role of 18 fluorodeoxyglucose positron emission tomography (PET) is limited for detection of primary hepatocellular carcinoma (HCC) due to low contrast to the tumor, and normal hepatocytes (background). The aim of the present study was to improve the contrast between the tumor and background by standardizing the input parameters of a digital contrast enhancement technique. Materials and Methods: A transverse slice of PET image was adjusted for the best possible contrast, and saved in JPEG 2000 format. We processed this image with a contrast enhancement technique using 847 possible combinations of input parameters (threshold m and slope e). The input parameters which resulted in an image having a high value of 2 nd order entropy, and edge content, and low value of absolute mean brightness error, and saturation evaluation metrics, were considered as standardized input parameters. The same process was repeated for total nine PET-computed tomography studies, thus analyzing 7623 images. Results: The selected digital contrast enhancement technique increased the contrast between the HCC tumor and background. In seven out of nine images, the standardized input parameters m had values between 150 and 160, and for other two images values were 138 and 175, respectively. The value of slope e was 4 in 4 images, 3 in 3 images and 1 in 2 images. It was found that it is important to optimize the input parameters for the best possible contrast for each image; a particular value was not sufficient for all the HCC images. Conclusion: The use of above digital contrast enhancement technique improves the tumor to background ratio in PET images of HCC and appears to be useful. Further clinical validation of this finding is warranted.

F LUORODEOXYGLUCOSE (FDG) is well established as a tumor-seeking agent that is taken up by a wide variety of malignant tumors. Several nonmalignant lesions also are FDG avid, as are normal organ systems that use glucose as part of their metabolism. Low-grade FDG uptake in muscles is part of the normal biodistribution pattern of FDG, especially during physical activity. When this uptake is symmetric and corresponds to the location of a specific group of muscles, it is easily recognizable. Accurate interpretation of asymmetric muscular activity is more difficult. Recognition of unusual patterns and the location of benign physiologic muscular uptake of FDG is important for avoiding misinterpretations of positron emission tomography (PET) images. I describe 4 cases with unusual muscular FDG uptake that was noted during whole-body FDG imaging of nondiabetic patients. CASE 2

Publisher Summary Fluorine chemistry in Japan developed without the influence of the US and European countries, as it were associated simply with basic and general scientific technologies. Scientists at the Government Industrial Research Institute of Nagoya (GIRIN) that later became the National Industrial Research Institute of Nagoya (NIRIN) in 1993, made the opening moves in 1952. An episode known as “the budding of Japan's fluorine chemicals industry” occurred in 1935 when the Daikin Company succeeded in producing CFC-12 (CF2C12). The development of a fluoropolymer industry was selected as one of the objectives after studying a 1945 US Department of Commerce report. Basic studies associated with this aim were commenced at GIRIN in 1952 under the leadership of Dr Rimpei Kojima in the inorganic chemistry section. His so-called fluorine chemistry group was soon reinforced by the arrival of new chemists, including Drs Nagase and Muramatsu. At GIRIN, the first work on fluoroorganic chemistry was conducted in parallel with experiments dealing with inorganic fluorides and centered on the preparation of chlorofluorocarbon precursors of fluoromonomers via Swarts-type reactions. The development of perfluorochemical-based oxygen carriers for use in “artificial blood” was a hot topic in the 1970s, and the Green Cross Corporation (Osaka, Japan) had introduced an emulsified mixture of PFDC (perfluorodecalin) and PFTPA (perfluorotrinpropylamine) as a blood substitute under the trade name Fluosol-DA. Improvements in Japan's economy from the 1960s onwards were reflected in the funding of GIRIN.

18-Fluorine fluorodeoxyglucose (FDG) PET-CT is a sensitive technique and hypermetabolic foci unrelated to the primary malignancy are not infrequently encountered. The aim of this study was to evaluate the clinical significance of unexpected focal FDG uptake within the breast in patients undergoing PET-CT for assessment of other malignancies.

Carcinoma of the prostate presents one of the major problems in urology. It has the highest incidence of all urogenital neoplasms in the male and is responsible for over 4000 deaths annually in the United Kingdom. Even when the diagnosis has been established there remain two important considerations in the management of these patients: (1) assessment of the extent of the disease to enable precise staging and (2) a reliable and accurate method of evaluating the progression of the disease or response to treatment in the absence of clinical symptoms and signs.

Scintigrams ( 18 -Fluorine) of the central skeleton and routine radiographic skeletal surveys have been compared in 100 patients, 50 of whom had an apparently "early" and 50 advanced mammary carcinoma. Routine scientigraphy was more sensitive and accurate than routine radiology for the detection of skeletal metastases in all regions of the central skeleton except the ischia and publis. In the routine skeletal scintigram, the ischium was the only region which was further than 6 centimeters from the collimator during the examination. The 18 Fluorine was excreted in the urine and the pubis may have been masked by its accumulation in the bladder during the examination of this region. Benign lesions which may be responsible for a localised increased uptake of isotope are usually seen on the radiograph. Routine radiographic skeletal surveys are therefore necessary to avoid scintigraphic "false" positives. With the combined reporting of radiographs and scintigrams, no false positives occurred.