Flourodeoxyglucose Positron Emission Research Articles

Predictors of outcome in a contemporary cardiac sarcoidosis population: Role of brain natriuretic peptide, left ventricular function and myocardial inflammation.

Cardiac sarcoidosis (CS) is a potentially fatal condition that varies in its clinical presentation. Here, we describe baseline characteristics at presentation along with prognosis and predictors of outcome in a sizable and deeply phenotyped contemporary cohort of CS patients. Consecutive CS patients seen at one institution were retrospectively enrolled after undergoing laboratory testing, electrocardiogram, echocardiography, cardiac magnetic resonance (CMR) imaging and 18 F-flourodeoxyglucose positron emission tomography (FDG-PET) at baseline. The composite endpoint consisted of all-cause mortality, aborted sudden cardiac death, major ventricular arrhythmic events, heart failure hospitalization and heart transplantation. A total of 319 CS patients were studied (67% male, 55.4 ± 12 years). During a median follow-up of 2.2 years (range: 1 month-11 years), 8% of patients died, while 33% reached the composite endpoint. The annualized mortality rate was 2.7% and the 5- and 10-year mortality rates were 6.2% and 7.5%, respectively. Multivariate analysis showed serum brain natriuretic peptide (BNP) levels (hazard ratio [HR] 2.41, 95% confidence interval [CI] 1.34-4.31, p = 0.003), CMR left ventricular ejection fraction (LVEF) (HR 0.96, 95% CI 0.94-0.98, p < 0.0001) and maximum standardized uptake value of FDG-PET (HR 1.11, 95% CI 1.04-1.19, p = 0.001) to be independent predictors of outcome. These findings remained robust for different patient subgroups. Cardiac sarcoidosis is associated with significant morbidity and mortality, particularly in those with cardiac involvement as the first manifestation. Higher BNP levels, lower LVEF and more active myocardial inflammation were independent predictors of outcomes.

The Use of 18F-FDG PET/CT Metabolic Parameters in Predicting Overall Survival in Patients Undergoing Restaging for Malignant Melanoma

Malignant melanoma is one of the more aggressive cancers in the skin, with an increasing incidence every year. Melanoma has a better prognosis if diagnosed early and survival tends to decrease once the disease has metastasized. Positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) has been used extensively over the past two decades in staging and assessing responses to therapy in patients with melanoma. Metabolic PET parameters have been demonstrated to be independent prognostic factors for progression-free survival (PFS) and overall survival (OS) in different malignancies, melanoma included. In our study, we evaluated the metabolic parameters of 18F-FDG PET/CT (flourodeoxyglucose positron emission tomography/computed tomography) in predicting the overall survival in patients with malignant melanoma who presented for restaging. Metabolic PET parameters (maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG)) of the primary tumor, as well as whole-body MTV and TLG of the metastatic disease, were measured. Survival curves for OS were constructed and mortality rates were determined using the different PET variables. Forty-nine patients who presented for a PET/CT restaging in melanoma were included in this study. We found that non-survivors had significantly higher median MTV (11.86 cm3 vs. 5.68 cm3; p-value = 0.022), TLG (3125 vs. 14; p-value = 0.0357), whole-body MTV (53.9 cm3 vs. 14.4 cm3; p-value = 0.0076) and whole-body TLG (963.4 vs. 114.6; p-value = 0.0056). This demonstrated that high MTV and TLG values of the primary tumor and whole-body TLG as quantified by 18F-FDG PET/CT were prognostic factors for overall survival. The findings may potentially guide clinicians in decision making and identifying patients with a poorer prognosis.

Focal nodular marrow hyperplasia: Imaging features of 53 cases.

To describe the characteristic imaging features of focal nodular marrow hyperplasia (FNMH). Retrospective review of all patients with a diagnosis of FNMH between January 2007 and September 2019. The study included 53 patients, 7 males and 46 females with a mean age of 58 years (range 12-95 years). All had MRI with conventional spin echo sequences showing a poorly defined round/oval lesion with mild T1W iso/hyperintensity compared to skeletal muscle, low T2W turbo spin echo (TSE) signal intensity (SI) compared to marrow fat and variable SI on STIR, but never associated with reactive marrow oedema. All 53 patients had follow-up MRI, with all lesions remaining stable or partially resolving. In-phase (IP) and out-of-phase (OP) chemical shift imaging (CSI) was obtained in 31 of these, with 28 (90.3%) showing >20% SI drop on the OP sequence, while 3 (9.7%) demonstrated <20% SI drop. CT was available in 26 cases, 17 (65.4%) showing mild medullary sclerosis. Single-photon emission computed tomography CT (SPECT-CT) was available in four cases and Flourodeoxyglucose positron emission tomography CT (FDG PET-CT) in 2, all showing increased uptake. Focal uptake was also seen in three of eight patients who had undergone whole body bone scintigraphy. Only one lesion was biopsied, confirming FNMH. The imaging appearances of FNMH have been described on various modalities, particularly MRI with emphasis on the role of IP and OP CSI typically demonstrating >20% SI reduction. FNMH should be recognised and treated as a 'do not touch' lesion which does not require biopsy or prolonged follow-up. We describe and clarify the imaging characteristics of FNMH on MRI, including CSI, CT and various nuclear medicine modalities. An imaging algorithm is suggested for allowing a non-invasive diagnosis.

18FDG-PET is sensitive tool for detection of extracranial tuberculous foci in central nervous system tuberculosis – Preliminary observations from a tertiary care center in northern India

PurposeTo study the role of 18FDG- PET (Flourodeoxyglucose positron emission tomography) in a) determining the extent of cranial and extra-cranial disease and b) diagnosis as well as prognosis of CNS TB (central nervous system tuberculosis) including TBM (tuberculous meningitis). Patients and methodsThis prospective observational study (n = 70) was carried out at a tertiary care institute in Northern India from 1.1.2017 to 30.6.2018. Diagnosis of TBM was made according to modified Ahuja's criteria. All patients were evaluated in detail and treated as per standard guidelines. All patients underwent 18FDG-PET scanning of brain and whole body at baseline. ResultsMean age was 35.2 ± 14.8 years. There were 37 men. Majority of patients (n = 47; 67.1%) were below 40 years of age. 43 (61.4%) patients were in stage II TBM. The mean duration of illness was 77 ± 101.9 days. Majority of patients presented with fever (94.3%), headache (90%) and vomiting (84.3%). MRI was abnormal at baseline in 67 (95.7%) of patients, most common abnormalities being meningeal enhancement (68.6%) and tuberculomas (57.1%). PET was abnormal in 66 (95.7%) of patients. All these patients had either lung lesions (n = 62, 88.6%) or lymphadenopathy (n = 61; 87.1%). 18FDG-PET revealed evidence of brain lesions in 52 (74.3%) patients. It revealed vertebral involvement in 19 (27.1%) and genitourinary lesions in 9 (12.9%) patients. PET evidence of lymphadenopathy correlated significantly (p = .04) with good outcome in CNS TB.Conclusion18FDG-PET does seem to have a promising role in initial evaluation of patients with CNS TB.

Epilepsy and neuropsychiatric comorbidities in mice carrying a recurrent Dravet syndrome SCN1A missense mutation

Dravet Syndrome (DS) is an encephalopathy with epilepsy associated with multiple neuropsychiatric comorbidities. In up to 90% of cases, it is caused by functional happloinsufficiency of the SCN1A gene, which encodes the alpha subunit of a voltage-dependent sodium channel (Nav1.1). Preclinical development of new targeted therapies requires accessible animal models which recapitulate the disease at the genetic and clinical levels. Here we describe that a C57BL/6 J knock-in mouse strain carrying a heterozygous, clinically relevant SCN1A mutation (A1783V) presents a full spectrum of DS manifestations. This includes 70% mortality rate during the first 8 weeks of age, reduced threshold for heat-induced seizures (4.7 °C lower compared with control littermates), cognitive impairment, motor disturbances, anxiety, hyperactive behavior and defects in the interaction with the environment. In contrast, sociability was relatively preserved. Electrophysiological studies showed spontaneous interictal epileptiform discharges, which increased in a temperature-dependent manner. Seizures were multifocal, with different origins within and across individuals. They showed intra/inter-hemispheric propagation and often resulted in generalized tonic-clonic seizures. 18F-labelled flourodeoxyglucose positron emission tomography (FDG-PET) revealed a global increase in glucose uptake in the brain of Scn1aWT/A1783V mice. We conclude that the Scn1aWT/A1783V model is a robust research platform for the evaluation of new therapies against DS.

Prognostic value of fluorine18 flourodeoxyglucose positron emission tomography/computed tomography in dogs with appendicular osteosarcoma.

BackgroundFactors indicative of a negative prognosis for appendicular osteosarcoma (OSA) in dogs are visible metastatic disease, location, and size of lesion. In human medicine maximum standard uptake value (SUVmax), as measured on a fluorine18 flourodeoxyglucose positron emission tomography/computed tomography (18F‐FDG PET/CT), is prognostic for survival for several tumor types.ObjectiveDetermine if SUVmax is associated with progression‐free interval (PFI) and determination of survival in dogs with appendicular OSA.AnimalsSixty‐two dogs with untreated appendicular OSA that had been staged with 18F‐FDG PET/CT.MethodsRetrospective analysis of the 18F‐FDG PET/CT was performed. Dogs were excluded from the study if they did not receive definitive intent treatment for their primary OSA and adjuvant chemotherapy with carboplatin, or had visible metastatic disease on initial imaging. A region of interest (ROI) was created around the primary tumor to measure SUVmax. Univariable and multivariable Cox proportional hazards analysis was performed to evaluate for associations between variables including SUVmax and outcome of PFI and overall survival (OS).ResultsMaximum standard uptake value of the primary tumor was significantly associated with the OS (P = .04) with adjustment for treatment type and monocyte count. The overall median survival time (OST) was 284 days (range, 39‐1293 days) with the OST of dogs having an SUVmax of ≥7.4 of 254 days (range, 98‐428 days) and dogs with an SUVmax of <7.4 of 680 days (range, 108‐811 days, P = .01).Conclusions and Clinical ImportanceMaximum standard uptake value as measured via 18F‐FDG PET/CT is significantly associated with survival in dogs with appendicular OSA with a high SUVmax being an indicator of a negative prognosis.

Resting regional brain activity correlates of verbal learning deficit in major depressive disorder

Memory deficits are reported in major depressive disorder (MDD). Prefrontal cortical and mesiotemporal cortical (MTC)/subcortical regions are involved in the Buschke Selective Reminding Task (SRT), a verbal list-learning task. To determine whether depression-related changes in resting brain metabolism explain (in part) the deficits in SRT performance found in MDD, statistical correlation maps were calculated between SRT total recall score (TR) and relative regional cerebral metabolic rate for glucose (rCMRglu), measured by [18F]-flourodeoxyglucose (FDG) positron emission tomography (PET), in unmedicated, depressed MDD patients (N = 29). Subsequently, to explore hypothesized loss of top-down control in MDD, we compared the correlations between rCMRglu of SRT-relevant regions of the dorsolateral prefrontal cortex (dlPFC) and amygdala in a larger cohort of MDD (N = 60; 29 inclusive) versus healthy controls (HC) (N = 43). SRT performance of patients is on average 0.5 standard deviation below published normative mean. TR and rCMRglu positively correlate in bilateral dorsomedial PFC, dlPFC, dorsal anterior cingulate; negatively correlate in bilateral MTC/subcortical regions, and cerebellum. rCMRglu in dlPFC correlates negatively with that in amygdala in HC but not in MDD. Depression-related changes present in FDG-PET measured resting brain activity may be in part responsible for memory deficit found in MDD.

F-18 Flourodeoxy Glucose Positron Emission Tomography/Computed Tomography Imaging in Infection and Inflammation

F-18 Flourodeoxy Glucose Positron Emission Tomography/Computed Tomography Imaging in Infection and Inflammation

Potential clinical implication of (18) F-FDG PET/CT in diagnosis of periprosthetic infection and its comparison with (18) F-Fluoride PET/CT.

The differentiation between septic and aseptic loosening of prosthetic hip joint is a major challenge for the clinician. This study assessed and compared the diagnostic accuracy of (18) F- flouro-deoxyglucose positron emission tomography/computed tomography ((18) F-FDG PET/CT) with (18) F-fluoride PET/CT for diagnosis of infection in the painful hip prosthesis. In this prospective study, we included the patients with painful hip prostheses with radiological or clinical suspicion of loosening, those who had given the written consent and scheduled for clinical and diagnostic evaluation before revision arthroplasty. To rule out the nature of loosening (septic vs. aseptic), all the patients underwent (18) F-Fluoride PET/CT and (18) F-FDG PET/CT. The reference standard for periprosthetic infection was based on histopathology and/or microbial culture and/or intraoperative findings. We prospectively evaluated 42 patients of hip prostheses before revision arthroplasty. Visual and semi-quantitative analysis of both the positron emission tomography (PET) images was done and the results were compared with a reference standard. The sensitivity, specificity, positive predictive value (PPV), negative predictive values (NPV) and accuracy of (18) F-FDG PET/CT were 93.7%, 92.3%, 88.2%, 96% and 92.8% respectively. The sensitivity, specificity, PPV, NPV and accuracy of (18) F-fluoride PET/CT were 75%, 96.1%, 92.3%, 86% and 88.1% respectively. FDG PET/CT has higher sensitivity, NPV and accuracy as compared to compared to Fluoride PET/CT and comparable specificity and PPV. Fluoride PET/CT had shown slightly higher specificity than FDG-PET/CT, but the overall diagnostic performance of FDG-PET/CT in periprosthetic infection is optimal in routine clinical practice and better than fluoride PET/CT.

Metastasizing Primary Malignant Melanoma of the Ovary: A Diagnostic Enigma

Abstract Background: Primary melanoma of the ovary is very rare; fewer than 50 cases have been reported to date. The diagnosis is challenging and is usually one of exclusion of the more-common metastatic diseases. This article describes such a case in detail and reviews relevant literature. Case: A 58-year-old perimenopausal woman presented with a 2-month history of pain and distension of the abdomen. On evaluation, she was found to have bilateral ovarian complex cysts with ascites. In view of her elevated CA 125 level and positive ascitic fluid cytology, she underwent a staging laparotomy. The final histopathology was reported as a malignant melanoma of the left ovary within a cystic teratoma with metastatic involvement of the right ovary, peritoneum, omentum, and mesentery. Results: Following surgery, this patient was evaluated with a whole body F18 flourodeoxyglucose positron emission tomography/computed tomography scan to look for any probable site of primary or other metastatic areas that had not rev...

Estimation of patient radiation dose from whole body 18F- FDG PET/CT examination in cancer imaging: a preliminary study

This study aims to estimate the radiation effective dose resulting from whole body fluorine-18 flourodeoxyglucose Positron Emission Tomography (18F-FDG PET) scanning as compared to conservative Computed Tomography (CT) techniques in evaluating oncology patients. We reviewed 19 oncology patients who underwent 18F-FDG PET/CT at our centre for cancer staging. Internal and external doses were estimated using radioactivity of injected FDG and volume CT Dose Index (CTDIvol), respectively with employment of the published and modified dose coefficients. The median differences of dose among the conservative CT and PET protocols were determined using Kruskal Wallis test with p < 0.05 considered as significant. The median (interquartile range, IQR) effective doses of non-contrasted CT, contrasted CT and PET scanning protocols were 7.50 (9.35) mSv, 9.76 (3.67) mSv and 6.30 (1.20) mSv, respectively, resulting in the total dose of 21.46 (8.58) mSv. Statistically significant difference was observed in the median effective dose between the three protocols (p < 0.01). The effective doses of whole body 18F-FDG PET technique may be effective the lowest amongst the conventional CT imaging techniques.

Utility of [18F] flourodeoxyglucose positron emission tomography (FDG-PET) to predict resectability after neoadjuvant therapy in patients with unresectable pancreatic cancer on CT scans.

357 Background: The standard imaging approach in patients with pancreatic cancer is contrast enhanced computed tomography (CT), however, Response Evaluation Criteria in Solid Tumors (RECIST) may not be adequate in evaluating response to neoadjuvant therapy. A growing body of evidence exists to suggest that there is additional useful information to be gained from the use of FDG-PET scans in this setting. Methods: We conducted an IRB approved retrospective chart review of patients with locally advanced or borderline resectable pancreatic adenocarcinoma who underwent neoadjuvant therapy at the University of Oklahoma and who had PET/CT imaging before and/or after neoadjuvant therapy between September 2006 and September 2013. Complete remission (CR) was defined as decrease in SUV to ≤ 3.0 or background, and partial response (PR) was defined as decrease in SUV from baseline, but &gt; 3.0. Results: A total of 13 patients underwent Whipple surgery after neoadjuvant therapy at our institution. Four patients (31%) had persistent unresectable disease on CT scans post-neoadjuvant therapy, but demonstrated CR (three patients) or PR (one patient; Pre-treatment SUV: 10.1, Post Treatment: 4.6) on the PET scan. These patients underwent Whipple surgery based on PET response. All four (100%) patients underwent R0 resection. Two patients (50%) received neoadjuvant chemo-radiation in addition to chemotherapy. Conclusions: Response on FDG-PET/CT can be a predictor of R0 resection in cases with evidence of unresectable disease on conventional CT scan. A protocol to study larger number of patients prospectively is being designed.

Dual time point imaging fluorine-18 flourodeoxyglucose positron emission tomography for evaluation of large loco-regional recurrences of breast cancer treated with electrochemotherapy

BackgroundElectrochemotherapy is a local anticancer treatment very efficient for treatment of small cutaneous metastases. The method is now being investigated for large cutaneous recurrences of breast cancer that are often confluent masses of malignant tumour with various degrees of inflammation. To this end 18-Flourine-Flourodeoxyglucose-Positron Emission Tomography/Computed Tomography (FDG-PET/CT) could be a method for response evaluation. However, a standard FDG-PET/CT scan cannot differentiate inflammatory tissue from malignant tissue. Dual point time imaging (DTPI) FDG-PET has the potential of doing so. The purpose of this study was to investigate if DTPI FDG-PET/CT could assess response to electrochemotherapy and to assess the optimal timing of imaging.Patients and methodsWithin a phase II clinical trial 11 patients with cutaneous recurrences had FDG-PET/CT scans at three time points: 60 min, 120 min and 180 min after FDG injection. The scans were performed before and 3 weeks after electrochemotherapy.ResultsA significant reduction in maximum standard uptake value at 60 min post injection was seen after treatment. Furthermore a change in the FDG uptake pattern was observed; from increasing uptake in up to 180 min post injection before treatment to stabilization of FDG uptake at 120 min post injection after treatment. The change in FDG uptake pattern over time lead to change of response in three target lesions; two lesions changed from stable metabolic disease to partial metabolic response and one lesion changed from partial metabolic response to stable metabolic disease. To ensure detection of the change in uptake pattern, scanning 60 and 180 min post injection seems optimal.ConclusionsThe present study shows that FDG-PET/CT 60 and 180 min after tracer injection is a promising tool for response evaluation of cutaneous recurrences of breast cancer treated with electrochemotherapy.

Association between the Alzheimer's disease-related hypometabolic convergence index and clinical ratings in cognitively normal older adults with and without significant fibrillar amyloid burden: Findings from the Alzheimer's Disease Neuroimaging Initiative

We previously developed a voxel-based hypometabolic convergence index (HCI) to characterize, in a single measurement, the extent to which the pattern and magnitude of hypometabolism in a person's flourodeoxyglucose positron emission tomography(FDG PET) image corresponds to that in patients with the clinical diagnosis of Alzheimer's dementia (Chen and Ayutyanont et al., 2010). In this study, we characterized and compared HCIs and their relationship with poorer clinical ratings in cognitively normal “fibrillar Aβ positive and negative” older adults from the Alzheimer's disease Neuroimaging Initiative (ADNI). Florbetapir PET scans from 225 cognitively normal subjects 76±6 years of age were used to characterize mean cortical-to-cerebellar standard uptake value ratios (SUVRs) and classify the images as fibrillar Aβ positive and negative using an SUVR threshold previously found to be associated with moderate or frequent neuritic plaques (Fleisher et al., 2011). FDG PET scans from 71 Aβ positive and 154 Aβ negative subjects were used to generate HCIs, compare this index, and relate them to lower MMSE and higher ADAS-Cog scores (i.e., measures of clinical severity) in the two subject groups. Aβ positive groups had significantly higher HCIs than the Aβ negative groups (p=0.0024). HCIs were significantly associated with poorer MMSE and ADAS-Cog scores in the Aβ positive group (r=-0.38, p=0.001 and r=0.36, p=0.002, respectively) but not in the Aβ negative group (r=0.007, p=0.936 and r=0.06, p=0.458, respectively). Fibrillar A b burden in cognitively normal older adults is associated with an AD-related index of cerebral hypometabolism, and this index is associated with poorer clinical ratings in those who are Aβ positive.

Comparison of nitrate augmented Tc-99m tetrofosmin gated SPECT imaging with FDG PET imaging for the assessment of myocardial viability in patients with severe left ventricular dysfunction

BackgroundOf various nuclear medicine techniques, F-18/flourodeoxyglucose (FDG) positron emission tomography (PET) is considered as the best modality for the assessment of viable myocardium (VM). In this study, we compared the diagnostic accuracy of nitrate augmented Tc-99m tetrofosmin gated G-single-photon emission computed tomography (SPECT) with FDG PET. Methods54 consecutive cases of angiographically proven CAD with severe LV dysfunction were enrolled in the study. The patients underwent Tc-99m tetrofosmin G-SPECT and FDG PET as per the standard protocols and were compared. ResultsSPECT data analysis indicated functional abnormalities in 661/918 myocardial segments. F-18 FDG PET revealed VM in 496/661 segments. The diagnostic accuracy of baseline NAC, postnitrate NAC, baseline AC, and postnitrate AC Tc-99m tetrofosmin SPECT was 84%, 87%, 90%, and 94%, respectively. κ values for NAC baseline, NAC postnitrate, AC baseline, and AC postnitrate Tc-99m tetrofosmin G-SPECT were 0.65, 0.70, 0.77, and 0.85, respectively. Attenuation correction revealed viability additionally in 46 segments which were non-viable on NAC postnitrate study (P < .001). Nitrate augmentation showed viability additionally in 25 segments which were non-viable on AC baseline scan (P = .004). On patient-based analysis FDG PET changes the management only in 13% (7/54) of patients. ConclusionsNitrate augmented AC Tc-99m tetrofosmin G-SPECT shows excellent (κ = .85) agreement with FDG PET. FDG PET changes management only in 13% of the patients. Tc-99m tetrofosmin G-SPECT being more widely available and cheaper imaging modality can be reliably used to detect VM where FDG PET is not available.

Brain imaging biomarkers for the Alzheimer’s Prevention Initiative

Alzheimer's disease (AD), the most common disabling impairment in older adults, takes an unacceptable toll on patients and families. With the growing number of people living to older ages, it is projected to afflict more than 100 million people around the world by 2050. While there is an urgent need, it takes too many cognitively normal (CN) individuals and too many years to evaluate presymptomatic AD treatments using traditional clinical endpoints. We and our colleagues have been using imaging techniques to detect the brain changes associated with the predisposition to AD in CN individuals with 2, 1 and 0 copies of the apolipoprotein E (APOE) e4 allele, the major late-onset AD susceptibility gene, and in CN presenilin 1 (PSEN1) mutation carriers and non-carriers from the world’s largest autosomal dominant early-onset AD kindred in Antioquia, Colombia; we developed several image-analysis techniques and a composite cognitive measure with improved power; and we estimated the sample sizes needed when using these endpoints. We recently proposed the Alzheimer’s Prevention Initiative (API) to help in the effort to launch an era in AD prevention research. The API will include preclinical AD treatment/biomarker development trials in individuals at increased genetic risk for early-onset and late-onset AD, an extremely large Colombian early-onset AD Prevention Registry; and an extremely large North American Alzheimer’s Prevention Registry to support several preclinical AD trials. The API’s first trial will test the anti-amyloid immunization therapy crenezumab in CN PSEN1 mutation carriers using the best established brain imaging and cerebrospinal fluid measurements and our composite cognitive measure as the primary clinical endpoint. It is intended to test an anti-amyloid agent in the preclinical treatment of AD, help determine the extent to which a treatment’s biomarker effects predict a clinical outcome, provide a better test of the amyloid hypothesis, and provide raw data and biological samples to the research community. With support from the U.S. National Institutes of Health, philanthropic funds from the Banner Alzheimer’s Institute, and Genentech, it is also intended to help provide a new paradigm for research collaboration in clinical trials. In this presentation, we will briefly introduce the crucial role of flourodeoxyglucose positron emission tomography (PET), amyloid PET, structural and functional MRI in the preclinical detection, tracking, and treatment of AD. We will present the novel image processing methods we have developed to help in this endeavor, as well as their implementation in the API’s preclinical treatment/biomarker development programs.

F-18 flourodeoxyglucose positron emission tomography/computed tomography findings in a case of hepatosplenic T-cell lymphoma

T-cell lymphoma (TCL) is a biologically diverse and uncommon group of lymphoid malignant diseases. Compared with its B-cell counterparts, TCL is notably more difficult to diagnose and manage owing to its rarity and biologic heterogeneity. Hepatosplenic TCL is an extremely rare subtype of TCL. A 37-year-old Indian male presented to his physician with swelling and pain in left hypochondrium. Clinical examination revealed pallor, icterus and massive splenomegaly. His blood examination revealed pancytopenia. His bone marrow biopsy was suggestive of lymphoma. Whole body F-18 flourodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scan revealed diffuse increased metabolic activity in massively enlarged spleen, liver and bone marrow. There was no evidence of metabolically active lymphadenopathy anywhere in the body. Guided by the FDG PET/CT findings, a liver biopsy was advised. Liver histopathology revealed the presence of hepatosplenic TCL. A final diagnosis of hepatosplenic TCL with liver, spleen and bone marrow involvement was made. Even though rare, hepatosplenic TCL should be considered as a possible diagnosis in patients presenting with similar clinical picture and FDG PET/CT scan findings.

Fluorodeoxyglucose positron emission tomography: emerging roles in the evaluation of putative Alzheimer's disease-modifying treatments

Alzheimer's disease (AD) is associated with characteristic and progressive reductions in flourodeoxyglucose positron emission tomography (FDG PET) measurements of the regional cerebral metabolic rate for glucose. These reductions begin years before the onset of symptoms, are correlated with clinical severity, and may help predict an affected patient's clinical course and neuropathological diagnosis. Like several other AD biomarkers, FDG PET has the potential to accelerate the evaluation of AD-modifying treatments, particularly in the earliest clinical and preclinical stages. This article considers FDG PET's role in the detection and tracking of AD, its emerging roles in the evaluation of disease-slowing treatments, some of the issues involved in the acquisition, analysis, and interpretation of FDG PET data, and the evidence needed to help qualify FDG PET and other biomarkers for use in the accelerated approval of AD-slowing treatments. It recommends scientific strategies and public policies to further establish the role of FDG PET and other AD biomarkers in therapeutic trials and find demonstrably effective disease-modifying and presymptomatic AD treatments as quickly as possible.

PET-CT findings in large vessel vasculitis presenting as FUO, a case report

There are increasing data demonstrating the role of flourodeoxyglucose positron emission tomography with computerized tomography fusion ((18)FDG PET-CT) in the diagnosis of large vessel vasculitides, including Takayasu arteritis and giant cell arteritis (Hara et al. 1999; Blockmans et al. 1999; Turlakow et al. 2001]. We report a case of large vessel giant cell arteritis involving the major branches of the aorta as detected on (18)FDG PET-CT. A 56-year-old woman returning to the USA after visiting her native Iraq presented to our rheumatology department with fever of unknown origin (FUO) of 2-month duration, night sweats, and arthralgias. The patient did not have claudication; systolic blood pressure measurements demonstrated a 20-mmHg difference between her arms. Infectious disease, malignancy, and collagen vascular disease workup was unrevealing. Temporal artery and bone marrow biopsies were negative. To exclude FUO of malignancy, (18)FDG PET-CT imaging was performed. The images demonstrated significant (18)FDG uptake (indicating increased metabolic activity) in a circumferential fashion along the aorta and its major braches, including the carotid, subclavian, and common iliac arteries. Contrast-enhanced CT imaging demonstrated wall thickening involving these vessels along with left subclavian vein thrombosis and findings consistent with superficial thrombophlebitis involving the right forearm, wrist, and hand. The combination of laboratory and imaging findings, including the characteristic inflammatory changes involving the large vessel walls as seen on CT, as well as the vessel wall hypermetabolism on FDG PET indicating active inflammation, resulted in the diagnosis of large vessel giant cell arteritis. The patient was treated with high-dose corticosteroids followed by a course of Immuran. Her symptoms resolved and a follow-up FDG PET-CT showed complete resolution of the large vessel hypermetabolism. (18)F-FDG PET-CT can be a useful and noninvasive tool in diagnostic evaluation of FUO by excluding a malignant etiology and providing unexpected information that aids in correct diagnosis.

FDG PET Brain Imaging in Neuropsychiatric Systemic Lupus Erythematosis With Choreic Symptoms

Abstract: Chorea is a rare manifestation of neuropsychiatric systemic lupus erythematosus, and is probably caused by immune-mediated hypofunction of the contralateral striatum. Conventional imaging with brain computed tomography or magnetic resonance imaging often fails to show any structural lesions. We report a case of systemic lupus erythematosus-associated chorea in which brain F-18 flourodeoxyglucose positron emission tomography imaging showed disturbances in striatal metabolism in the absence of structural damage on magnetic resonance imaging. A follow-up positron emission tomography scan showed normalization of striatal metabolism, which was correlated with clinical remission.