Negative association of pretreatment cigarette use with smoking-induced striatal dopamine release in smokers receiving bupropion treatment.

Background And Objectives: In an effort to help identify factors that maintain heavy smoking, this study tested the association of pretreatment cigarette use (cigarettes per day) with striatal dopamine release during smoking-cessation treatment.

Methods: Thirteen regular smokers (≥10 cigarettes per day) were evaluated on parameters of smoking behavior, and they entered a smoking cessation treatment protocol, including bupropion administration and individual counseling for 2 months. On week 7 of treatment, 10 of the participants underwent brain scans using [(11) C]raclopride with positron emission tomography to assess smoking-induced dopamine release in the caudate nucleus and putamen, inferred from changes in dopamine D2 -type receptor availability.

Gated blood pool SPECT: The estimation of right ventricular volume and function is algorithm dependent in a clinical setting.

Background: Gated blood pool SPECT (GBPS) requires further validation for the assessment of the right ventricle (RV). This study evaluated three algorithms: BP-SPECT, QBS, and TOMPOOL (results are referred using this order). We compared (1) their "quantitative-accuracy": estimation of RV ejection fraction (EF), end-diastolic volume (EDV), and cardiac output (CO); (2) their "qualitative-accuracy": threshold values allowing diagnosing an impairment of the RV function; (3) their reproducibility: inter-observer relative variability (IOV).

Nonsurgical giant cell tumour of the tendon sheath or of the diffuse type: are MRI or 18F-FDG PET/CT able to provide an accurate prediction of long-term outcome?

Purpose: To investigate whether MRI (RECIST 1.1, WHO criteria and the volumetric approach) or (18)F-FDG PET/CT (PERCIST 1.0) are able to predict long-term outcome in nonsurgical patients with giant cell tumour of the tendon sheath or of the diffuse type (GCT-TS/DT).

Is TOMPOOL (gated blood-pool SPECT processing software) accurate to diagnose right and left ventricular dysfunction in a clinical setting?

Background: The assessment of right ventricular function is crucial for management of heart disease. TOMPOOL is a software that processes data acquired with Tomographic Equilibrium Radionuclide Ventriculography. In this report, TOMPOOL's diagnostic accuracy and inter-observer reproducibility were assessed in a cohort of patients with various etiologies of ventricular dysfunction.

Gating, enhanced gating, and beyond: information utilization strategies for motion management, applied to preclinical PET.

Background: Respiratory gating and gate optimization strategies present solutions for overcoming image degradation caused by respiratory motion in PET and traditionally utilize hardware systems and/or employ complex processing algorithms. In this work, we aimed to advance recently emerging data-driven gating methods and introduce a new strategy for optimizing the four-dimensional data based on information contained in that data. These algorithms are combined to form an automated motion correction workflow.

Brain activation and heart rate during script-driven traumatic imagery in PTSD: preliminary findings.

Patients with posttraumatic stress disorder (PTSD) experience psychological and physiological distress. However, imaging research has mostly focused on the psychological aspects of the disorder. Considered an expression of distress, heart rate (HR) in PTSD is often elevated.

11C-acetate PET/CT in bladder urothelial carcinoma: intraindividual comparison with 11C-choline.

Objective: We present a first study of the use of 11C-acetate (ACET) positron emission tomography (PET)/computed tomography (CT) in bladder urothelial carcinoma (UC) and an intraindividual comparison with 11C-choline (CHOL) PET/CT.

Methods: Fourteen patients with biopsy-proven UC (11 T2, 3 T1 refractory to treatment) were prospectively evaluated before radical cystectomy and excision of pelvic lymph nodes (LNs), with ACET and CHOL PET/CT scans performed within 1 week. Image acquisition started 5 minutes after intravenous injection of 12 to 14 mCi for both tracers.

Ga-68 DOTA-NOC uptake in the pancreas: pathological and physiological patterns.

Objective: Gallium-68 (Ga-68) DOTA-1-NaI3-octreotide (DOTA-NOC) positron emission tomography (PET)/computed tomography (CT) is increasingly used for neuroendocrine tumors (NETs), often found primarily in the pancreas. However, physiologic uptake of DOTA-NOC has been described in the uncinate process of the pancreas. We studied DOTA-NOC uptake in this organ.

Hyperintensities on T2-weighted images in the basal ganglia of patients with major depression: cerebral perfusion and clinical implications.

White matter hyperintensities on T2-weighted images (WMH T2-WI) are prevalent in depressed, particularly elderly, patients. In an earlier study we used structural magnetic resonance imaging (MRI) to study 37 depressed and 27 healthy control subjects to show that prevalence of WMH T2-WI is higher in depressed patients and that severity of depression and cognitive impairment is associated with presence of WMH T2-WI in basal ganglia. The occurrence of WMH T2-WI in depression may also be associated with cerebrovascular deficiency, although this association has not been adequately studied.

68Ga-DOTA-NOC PET/CT imaging of neuroendocrine tumors: comparison with ¹¹¹In-DTPA-octreotide (OctreoScan®).

Purpose: Recent data have indicated that ⁶⁸Ga-DOTA-NOC positron emission tomography/X-ray computed tomography (PET/CT) may yield improved images in a shorter acquisition protocol than ¹¹¹In-DTPA-octreotide (OctreoScan®, OCT). Therefore, we performed a prospective comparison of ⁶⁸Ga-DOTA-NOC and OCT for the detection of neuroendocrine tumors (NETs).

Methods: Nineteen patients (eight carcinoid, nine pancreatic NETs, and two NE carcinoma of unknown origin) with previous positive OCT scans underwent ⁶⁸Ga-DOTA-NOC PET/CT and OCT single-photon emission computed tomography imaging for staging or follow-up.

18F-fluorodeoxyglucose-PET/CT imaging of lungs in patients with cystic fibrosis.

Background: Airway inflammation plays a critical role in the progression of cystic fibrosis (CF) lung disease, and in the destruction of airways and lung parenchyma. Current methods to assess CF lung disease (BAL, spirometry, and high-resolution CT scanning), do not always accurately reflect actual disease states. Fluorodeoxyglucose (FDG)-PET scanning has been used previously to image infection and inflammation.

Cerebral perfusion after a 2-year remission in major depression.

Although patients suffering from major depression respond to antidepressant treatment within several weeks, full reinstatement of premorbid capabilities requires much longer. Nevertheless, most research in major depression seeking the pathophysiological correlates of remission has focused upon the acute post-treatment period. Brain imaging research offers no exception.

Added value of SPECT/CT for correlation of MIBG scintigraphy and diagnostic CT in neuroblastoma and pheochromocytoma.

Objective: In pheochromocytoma and neuroblastoma, pathologic findings on metaiodobenzylguanidine (MIBG) scintigraphy (planar and SPECT) and on diagnostic CT are sometimes difficult to correlate. Furthermore, CT reading may be impaired by anatomic distortion after surgery or irradiation and if contrast agent is not injected. The present study evaluates the impact of SPECT/CT fusion images on correlation and image analysis of both techniques.

Brain imaging study of the acute effects of Delta9-tetrahydrocannabinol (THC) on attention and motor coordination in regular users of marijuana.

Procedure: Twelve regular users of marijuana underwent two positron emission tomography (PET) scans using [18F] Fluorodeoxyglucose (FDG), one while subject to the effects of 17 mg THC, the other without THC. In both sessions, a virtual reality maze task was performed during the FDG uptake period.

Results: When subject to the effects of 17 mg THC, regular marijuana smokers hit the walls more often on the virtual maze task than without THC.

99mTc-HMPAO SPECT study of cerebral perfusion after treatment with medication and electroconvulsive therapy in major depression.

Unlabelled: Compromised regional cerebral blood flow (rCBF) in major depressive disorder may be partly reversed by successful antidepressant treatment. However, it is not known if the reversal of rCBF compromise is dependent on the mode of antidepressant treatment. The current study aimed to address this question.

Cerebral glucose utilization and platelet mitochondrial complex I activity in schizophrenia: A FDG-PET study.

Altered cerebral energy metabolism and mitochondrial dysfunction in periphery and in brain are implicated in the pathophysiology of schizophrenia. This study investigated whether cerebral glucose metabolism (rCGM) abnormalities are linked to altered mitochondrial complex I activity in the periphery, in schizophrenia. Sixteen schizophrenic patients, 8 with total positive PANSS score >or=20 (high positive schizophrenics; HPS), and 8 with total positive score View Article and Find Full Text PDF

Chiral dimethylamine flutamide derivatives--modeling, synthesis, androgen receptor affinities and carbon-11 labeling.

Most prostate cancers are androgen dependent upon initial diagnosis. On the other hand, some very aggressive forms of prostate cancer were shown to have lost the expression of the androgen receptor (AR). Although the AR is routinely targeted in endocrine treatment, the clinical outcome remains suboptimal.

Contribution of 11C-choline positron emission tomography/computerized tomography to preoperative staging of advanced transitional cell carcinoma.

Purpose: Current imaging modalities for preoperative staging of advanced transitional cell carcinoma of the bladder or upper urinary tract are not sensitive for detection of metastases. This study examines the contribution of 11C-choline positron emission tomography/computerized tomography to preoperative staging of transitional cell carcinoma.

Materials And Methods: We prospectively evaluated 18 patients with 19 advanced transitional cell carcinomas (17 bladder tumors and 2 upper tract transitional cell carcinomas).

Brain SPECT study of common ground between hypothyroidism and depression.

Hypothyroidism and major depressive disorder (MDD) share neuropsychiatric features. Cerebral perfusion deficits are found in both disorders. We compared regional cerebral blood flow (rCBF) in hypothyroidism and MDD to determine if clinical similarities are mediated by common neurocircuitry.

Technetium-99m-MIBI SPECT/CT in primary hyperparathyroidism.

The novel trend toward focused parathyroidectomy requires precise preoperative localization of the parathyroid adenoma in patients with primary hyperparathyroidism (PHPT). The present study evaluated the impact of hybrid single photon emission computed tomography/computed tomography (SPECT/CT), using 99mTc-sestamibi (MIBI), on the surgical management of these patients. In a retrospective study of 36 patients with PHPT, SPECT/CT was undertaken when planar 99mTc-MIBI scintigraphy was negative or when an ill-defined focus in the neck or an ectopic site on planar views was visualized.

In vivo measurement of brain monoamine oxidase B occupancy by rasagiline, using (11)C-l-deprenyl and PET.

Unlabelled: In recent years, monoamine oxidase B (MAO-B) inhibitors have become widely used in the treatment of early-stage Parkinson's disease. (11)C-l-deprenyl PET has been used by others to characterize MAO-B ligands in terms of their in vivo potency toward MAO-B and duration of action. In this study, we used (11)C-l-deprenyl PET to demonstrate the specific binding characteristics of the new irreversible selective MAO-B inhibitor rasagiline in 3 healthy volunteers.

Prostate cancer PET bioprobes: synthesis of [18F]-radiolabeled hydroxyflutamide derivatives.

Approximately 80-90% of prostate cancers are androgen dependent at initial diagnosis. The androgen receptor (AR) is present in most advanced prostate cancer specimens and is believed to have a critical role in its development. Today, treatment of prostate cancer is done by inhibition of AR using antiandrogens such as flutamide (pro-drug of hydroxyflutamide), nilutamide, and bicalutamide.

Measurements of occupational exposure for a technologist performing 18F FDG PET scans.

Radiation doses to one PET technologist performing 100 18F FDG (18F fluorodeoxyglucose) imaging procedures were measured in a clinical setting using two types of thermoluminescent dosimeter (TLD) badges, one finger-ring TLD and one electronic pocket dosimeter (EPD). 18F FDG was handled either with unshielded or with viewing window tungsten shielded syringes. The resulting doses using unshielded syringes were 13.