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BACKGROUND The clinical utility of fatty meal stimulated cholescintigraphy particularly using a standardized formulation in patients with suspected functional gallbladder disorder has not been extensively studied. We present our seven-year clinical experience using an Ensure plus protocol. METHODS A retrospective study was performed on patients undergoing stimulated cholescintigraphy using Ensure Plus for evaluation of suspected functional gallbladder disorder. A gallbladder ejection fraction (GBEF) of

Introduction Suppression of physiological myocardial FDG activity is vital in patients undergoing PET/CT for assessment of known or suspected cardiac sarcoidosis. This study aims to evaluate the efficacy of physiological myocardial FDG suppression following a protocol change to a 24-h high fat very low carbohydrate (HFVLC) diet and prolonged fast. Methods A retrospective review of patients undergoing FDG PET/CT for the evaluation of cardiac sarcoidosis was performed. Prior to June-2018, patients were prepared with a single very high-fat low carbohydrate meal followed by a 12-18 h fast (group 1). After June-2018, a protocol change was initiated with patients prepared with a HFVLC diet for 24-h followed by a 12-18 h fast (group 2). Focal myocardial activity was classified as positive, absent activity as negative and diffuse/focal on diffuse activity as indeterminate. Results A total of 94 FDG PET/CT scans were included with 46 scans in group 1 and 48 scans in group 2. Studies were classified as positive, negative or indeterminate in 25 (54%), 7 (15%) and 14 (30%) scans in group 1 and in 13 (27%), 33 (69%) and 2 (4%) scans in group 2, respectively. In scans classified as negative, myocardial FDG activity was less than mediastinal blood pool activity in 5/7 (71%) scans in group 1 and 33/33 (100%) scans in group 2. Conclusion Excellent myocardial FDG suppression can be achieved using a 24-h HFVLC diet and prolonged fast, resulting in a very low indeterminate scan rate in patients with known or suspected cardiac sarcoidosis.

We report an unusual case of a 59-year-old man with recurrent right ear melanoma resulting in perineural spread to the right greater auricular nerve. Direct perineural spread to the greater auricular nerve is not commonly reported in melanoma. Our case demonstrates perineural spread along the greater auricular nerve on 18F-FDG PET/CT and MRI. This finding was supported by intraneural invasion noted at the surgical margin of the wide local excision of the right helix melanoma. Resolution of FDG activity and improved MRI appearances of the right greater auricular nerve were seen after immunotherapy treatment.

Lu-177-labeled prostate-specific membrane antigen (PSMA) radioligand therapy using PSMA-617 and PSMA-I&T ligands (Lu-177-PRLT) is an emerging treatment in metastatic castration-resistant prostate cancer (mCRPC). This retrospective study evaluates clinical outcomes of Lu-177-PRLT in earlier and later phases of mCRPC grouped by previous taxane chemotherapy. Methods: A retrospective analysis was performed on 167 patients with mCRPC who underwent Lu-177-PRLT between March 2013 and December 2016. Patients were classified as either taxane chemotherapy pretreated (T-pretreated) or naive (T-naive) depending on whether they had received taxane-based chemotherapy prior to Lu-177-PRLT. Clinical outcome for T-pretreated and T-naive patients was assessed by overall survival (OS), radiographic progression-free survival, and prostate-specific antigen (PSA) response rate. Univariate and multivariable analyses were performed for both T-pretreated and T-naive patients to determine predictors of outcome. Toxicity was categorized by the Common Terminology Criteria for Adverse Events (version 4.03). Results: Of the 167 patients treated with Lu-177-PRLT, 83 were T-pretreated and 84 were T-naive. At baseline, T-pretreated patients had overall poorer performance status, a higher prevalence of bone metastases, higher PSA levels, lower hemoglobin levels, higher alkaline phosphatase (ALP) levels and had received more additional therapies compared with T-naive patients. Median OS was 10.7 mo for T-pretreated patients and 27.1 mo for T-naive patients. Median radiographic progression-free survival was 6.0 mo for T-pretreated patients and 8.8 mo for T-naive patients. PSA response assessment was evaluable in 132 patients and seen in 25 of 62 (40%) T-pretreated patients and 40 of 70 (57%) T-naive patients. Significant determinates of inferior OS in multivariable analysis for T-pretreated patients were poorer performance status, lower cumulative administered activity, and lower baseline hemoglobin. Higher baseline alkaline phosphatase was the only significant determinate of inferior OS in multivariable analysis for T-naive patients. Overall Lu-177-PRLT was safe, with minimal adverse effects evident during follow-up in both T-pretreated and T-naive patients. Conclusion: Lu-177-PRLT is a promising therapy in mCRPC, with encouraging outcomes and minimal associated toxicity seen in both our T-naive and heavily pretreated patient cohorts.

The aim was to investigate normal patterns of brain metabolism determined by F-fluorodeoxyglucose positron emission tomography (FDG PET)/MRI during childhood and adolescence.A retrospective analysis was carried out on all paediatric patients who underwent FDG PET/MRI at our institution between March 2016 and August 2017. Exclusion criteria were neurological disease, central nervous system metastases, previous chemotherapy/radiotherapy, general anaesthesia/sedation and medications suspected to affect cerebral metabolism. Standardized uptake value (SUV)mean and SUVmax were calculated for 12 brain grey matter regions. Subgroup analysis of childhood (≤10 years old) and adolescence (≥11 years old) was also carried out.From 492 PET/MRI scans, 28 patients (11 children, 17 adolescents) were deemed representative of normal brain metabolism. SUVmean and SUVmax increased with age in all regions. The highest rates of increasing SUVmean were in the thalamus, basal ganglia, frontal lobes, insula and occipital lobes. Higher SUVmean was found in the right frontal, right lateral temporal, right temporal pole, right cingulate/paracingulate, right thalamus, left occipital, left basal ganglia, left insula and left cerebellum compared with the contralateral side. This SUVmean asymmetry was present in both childhood and adolescence in the majority of regions. The highest rates of increasing SUVmax with age were in the occipital lobes, frontal lobes, thalamus and central region. There was no asymmetry in SUVmax in the majority of regions.This FDG PET/MRI study shows that normal brain metabolism measured by SUVmean and SUVmax increases with age in all regions, proceeding at different rates between distinct anatomical sites. Our results suggest that there is mild asymmetry in SUVmean, but mostly symmetric SUVmax during normal development.

Increasing brown adipose tissue (BAT) activity is a possible therapeutic strategy to increase energy expenditure and glucose and lipid clearance to ameliorate obesity and associated comorbidities. The thiazolidinedione (TZD) class of glucose-lowering drugs increase BAT browning in preclinical experimental models but whether these actions extend to humans in vivo is unknown. The aim of this study was to determine the effect of pioglitazone treatment on adipocyte browning and adaptive thermogenesis in humans.We first examined whether pioglitazone treatment of cultured human primary subacromioclavicular-derived adipocytes induced browning. Then, in a blinded, placebo-controlled, parallel trial, conducted within the Baker Institute clinical research laboratories, 14 lean male participants who were free of cardiometabolic disease were randomised to receive either placebo (lactose; n = 7, age 22 ± 1 years) or pioglitazone (45 mg/day, n = 7, age 21 ± 1 years) for 28 days. Participants were allocated to treatments by Alfred Hospital staff independent from the study via electronic generation of a random number sequence. Researchers conducting trials and analysing data were blind to treatment allocation. The change in cold-stimulated BAT activity, assessed before and after the intervention by [Pioglitazone significantly increased in vitro browning and adipogenesis of adipocytes. In the clinical trial, cold-induced BAT maximum standardised uptake value was significantly reduced after pioglitazone compared with placebo (-57 ± 6% vs -12 ± 18%, respectively; p 0.05). BAT total glucose uptake followed a similar but non-significant trend (-50 ± 10% vs -6 ± 24%, respectively; p = 0.097). Pioglitazone increased total and lean body mass compared with placebo (p 0.05). No other changes between groups were detected.The disparity in the actions of pioglitazone on BAT between preclinical experimental models and our in vivo human trial highlight the imperative to conduct human proof-of-concept studies as early as possible in BAT research programmes aimed at therapeutic development. Our clinical trial findings suggest that reduced BAT activity may contribute to weight gain associated with pioglitazone and other TZDs.ClinicalTrials.gov NCT02236962 FUNDING: This work was supported by the Diabetes Australia Research Program and OIS scheme from the Victorian State Government.

Background There has been limited examination of the performance of glomerular filtration rate estimation (eGFR) equations in lung transplant populations. This study aimed to compare the performance of serum creatinine and cystatin C based eGFR equations with Tc-99m diethylenetriaminepentaacetic acid (DTPA) GFR measurements in individuals with end-stage lung disease, either prior to, or following, lung transplantation. Methods In this prospective observational study, participants underwent GFR measurements with Tc-99m Pentetate. Measured results were compared with GFR estimates derived from estimation equations [4-variable Modification of Diet in Renal Disease, Cockcroft-Gault, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine, cystatin C and creatinine-cystatin C combined equations]. Results Ninety-seven individuals were studied (77 post- and 20 wait-listed for transplantation). Median (range) radionucleotide GFR was 56.7 ml/min/1.73 m2 (22.8–109.2 ml/min/1.73 m2). In the study cohort as a whole, the CKD-EPI creatinine-cystatin C combined equation showed the highest performance, but was only slightly superior to the CKD-EPI creatinine equation. However, in individuals with cystic fibrosis, low arm muscle mass and/or low body mass index, all of the creatinine-based equations showed unacceptable performance. In these subgroups, improved GFR estimation was seen with the CKD-EPI cystatin C equation, and predictions were better still using the CKD-EPI creatinine-cystatin C combined equation. Conclusions This study shows adequate predictive ability of CKD-EPI creatinine in the cohort as a whole, but unacceptable performance in patients with cystic fibrosis, low arm muscle mass and/or low body mass index. Our findings demonstrate that cystatin C may be a preferable filtration marker in these subgroups.

Background Macrophage migration inhibitory factor ( MIF ) is a key regulator of inflammatory responses, including in the heart. Plasma MIF is elevated early in the course of acute myocardial infarction. In this study, we hypothesized that plasma MIF may also be increased in acute myocardial ischemia. Methods and Results Patients undergoing cardiac stress test (stress nuclear myocardial perfusion scan or stress echocardiography) were recruited. Twenty‐two patients had a stress test indicative of myocardial ischemia and were compared with 62 patients who had a negative stress test. Plasma MIF was measured by ELISA before and after the stress test. MIF was also measured in patients with peripheral arterial occlusive disease before and after exercise causing claudication. Gene and protein expression of MIF was measured in mouse cardiac and skeletal muscle tissue by real‐time polymerase chain reaction and western blot, respectively. Plasma MIF was elevated at 5 and 15 minutes after stress (relative to before stress) in patients with a positive test, compared with those with a negative test. In contrast, high‐sensitivity troponin T and C‐reactive protein were not altered after stress in either group. MIF was not altered after exercise in PAOD patients, despite the occurrence of claudication, suggesting that plasma MIF is not a marker for skeletal muscle ischemia. This may be explained by a lower gene and protein expression of MIF in skeletal muscle than the heart. Conclusions Our results suggest that plasma MIF is an early marker for acute myocardial ischemia.

Background It is unclear how to predict which patients will respond to Y-90 radiosynoviorthesis. The aim of this study is to correlate clinical outcomes following Y-90 radiosynoviorthesis with bremsstrahlung and Y-90 PET/CT imaging findings. Methods Fifty-one joints underwent bremsstrahlung planar and Y-90 PET/CT imaging following Y-90 radiosynoviorthesis. The Y-90 distribution pattern on bremsstrahlung planar imaging was classified as diffuse or non-diffuse and compared with the intra or extra-articular location of activity on Y-90 PET/CT. Treatment response was assessed by patients and clinicians at 6 months. In patients who underwent bremsstrahlung SPECT, side-by-side comparison with PET was performed with image quality/resolution scored using a five-point-scale. Findings Bremsstrahlung planar images were classified as diffuse in 33/51 (65 %) and non-diffuse in 18/51 (35 %) scans. There was no association between treatment response and the bremsstrahlung planar imaging pattern. PET/CT confirmed an intra-articular location in all 33/33 (100 %) diffuse scans and an extra-articular location in 3/18 (17 %) non-diffuse scans. Of the three joints with extra-articular activity, none had any treatment response. Excluding these three joints, there remained no association between the bremsstrahlung planar imaging pattern and treatment response. Of the 42 joints imaged with SPECT, PET image quality/resolution was classified as superior in 40 (95 %). In one patient with extra-articular activity on PET/CT, SPECT/CT was unable to definitively localise the activity to the intra or extra-articular space. Conclusions The distribution pattern on bremsstrahlung planar imaging did not correlate with clinical outcome following Y-90 radiosynoviorthesis in our study population. However, in patients with non-diffuse planar imaging patterns, Y-90 PET/CT should be considered to exclude extra-articular activity with PET providing superior image quality compared to SPECT.

The baseline insulin data given in Table 1 for the placebo group were incorrectly reported as 51 ± 10 pmol/l instead of 48 ± 10 pmol/l. This mistake also impacts on data reported in Table 4. The authors also note an error in the reported change in noradrenaline levels, from pre- to post-pioglitazone treatment (Table 4). The relevant rows from Tables 1 and 4 are reproduced here, with corrected data shown in bold. These corrections do not change the statistical significance of any comparison. (Table presented.).

Intrapancreatic accessory spleens are relatively uncommon and can be difficult to distinguish from neuroendocrine tumours on CT, MRI and somatostatin receptor scintigraphy. We present the case of a 26-year-old woman with an incidentally diagnosed pancreatic lesion confirmed to be an intrapancreatic accessory spleen on Tc-99m heat-denatured red blood cell single photon emission computed tomography/CT.