Radiation segmentectomy for curative intent of unresectable very early to early stage hepatocellular carcinoma (RASER): a single-centre, single-arm study.

Background: Unresectable solitary very early to early stage hepatocellular carcinoma is managed with ablation for curative intent. Radiation segmentectomy is a treatment option that delivers radioactive yttrium (Y)-bound microspheres transarterially to a segment of liver. The aim of this study was to assess the safety and efficacy of radiation segmentectomy in patients with unresectable hepatocellular carcinoma deemed unfavourable for ablation.

Tumour-to-normal tissue (T/N) dosimetry ratios role in assessment of Y selective internal radiation therapy (SIRT).

Objective: The purpose of our work is to assess the role of tumour-to-normal tissue (T/N) dosimetry ratios for predicting response in patients undergoing locoregional therapy to the liver with Y microspheres.

Methods: A total of 39 patients (7 female:32 male, mean age 68.3 ± 7.

An estimate of Y dosimetry for bremsstrahlung SPECT/CT imaging in liver therapy with Y microspheres.

Objective: Bremsstrahlung SPECT/CT (bSPECT/CT) is one of the most common methods for post-therapy imaging in Y microspheres selective internal radiation therapy (SIRT) of liver cancers. Here, we are proposing a simple approach using bSPECT/CT to estimate mean absorbed dose to the liver in patients undergoing treatment with Y microspheres.

Materials And Methods: In our previous study comparing Y dosimetry obtained using bSPECT/CT vs PET/CT, we found that there was a large difference between the mean absorbed dose values to the whole-liver.

Comparison of posttherapy Y positron emission tomography/computed tomography dosimetry methods in liver therapy with Y microspheres.

The aim of our study was to compare dosimetry methods for yttrium-90 (Y) positron emission tomography/computed tomography (PET/CT). Twenty-five patients were taken to a PET/CT suite following therapy with Y microspheres. The low mA, nondiagnostic CT images were used for attenuation correction and localization of the Y microspheres.

Brain and blood biomarkers of tauopathy and neuronal injury in humans and rats with neurobehavioral syndromes following blast exposure.

Traumatic brain injury (TBI) is a risk factor for the later development of neurodegenerative diseases that may have various underlying pathologies. Chronic traumatic encephalopathy (CTE) in particular is associated with repetitive mild TBI (mTBI) and is characterized pathologically by aggregation of hyperphosphorylated tau into neurofibrillary tangles (NFTs). CTE may be suspected when behavior, cognition, and/or memory deteriorate following repetitive mTBI.

Quantitative comparison of pre-therapy Tc-macroaggregated albumin SPECT/CT and post-therapy PET/MR studies of patients who have received intra-arterial radioembolization therapy with Y microspheres.

Objective: The aim of our study was to compare yttrium -90 (Y) dosimetry obtained from pre-therapy Tc-macroaggregated albumin (MAA) SPECT/CT versus post-therapy PET/MRI imaging among patients with primary or metastatic hepatic tumors.

Materials And Methods: Prior to Y radioembolization (RE), 32 patients underwent a scan using MAA mimicking Y distribution. After RE with Y microspheres, the patients were imaged on a PET/MRI system.

Comparison of PET/CT and PET/MR imaging and dosimetry of yttrium-90 (Y) in patients with unresectable hepatic tumors who have received intra-arterial radioembolization therapy with Y microspheres.

Background: The aim of our study was to compare Y dosimetry obtained from PET/MRI versus PET/CT post-therapy imaging among patients with primary or metastatic hepatic tumors. First, a water-filled Jaszczak phantom containing fillable sphere with Y-chloride was acquired on both the PET/CT and PET/MRI systems, in order to check the cross-calibration of the modalities. Following selective internal radiation therapy (SIRT) with Y microspheres, 32 patients were imaged on a PET/CT system, immediately followed by a PET/MRI study.

Multi institutional quantitative phantom study of yttrium-90 PET in PET/MRI: the MR-QUEST study.

Background: Yttrium-90 (Y) radioembolization involves the intra-arterial delivery of radioactive microspheres to treat hepatic malignancies. Though this therapy involves careful pre-treatment planning and imaging, little is known about the precise location of the microspheres once they are administered. Recently, there has been growing interest post-radioembolization imaging using positron-emission tomography (PET) for quantitative dosimetry and identifying lesions that may benefit from additional salvage therapy.

Comparison of Standardized Uptake Value Ratio Calculations in Amyloid Positron Emission Tomography Brain Imaging.

Amyloid positron emission tomography (PET) imaging with florbetapir F (F-AV-45) allows assessment of cerebral amyloid load and can be used in the evaluation of progression of Alzheimer's disease (AD) and other dementias associated with b-amyloid. However, cortical amyloid deposition can occur in healthy cases, as well as in patients with AD and quantification of cortical amyloid burden can improve the F-AV-45 PET imaging evaluations. The quantification is mostly performed by cortical-to-cerebellum standardized uptake value ratio (SUVr).

Evaluation of diabetic foot infection in nuclear medicine.

Diabetic foot infection is not only the most common cause of hospitalization among diabetic patients, but is also associated with high morbidity, mortality and major utilization of the resources. Managing diabetic patients with suspected foot infection is highly dependent on an early and accurate determination of its presence and location. Medical imaging is often used in the workup of these patients, as clinical diagnosis of osteomyelitis is often difficult, and invasive bone biopsy is infrequently used due to many limitations.

Cerebral [ F]T807/AV1451 retention pattern in clinically probable CTE resembles pathognomonic distribution of CTE tauopathy.

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disorder most commonly associated with repetitive traumatic brain injury (TBI) and characterized by the presence of neurofibrillary tangles of tau protein, known as a tauopathy. Currently, the diagnosis of CTE can only be definitively established postmortem. However, a new positron emission tomography (PET) ligand, [F]T807/AV1451, may provide the antemortem detection of tau aggregates, and thus various tauopathies, including CTE.

Optimization of yttrium-90 PET for simultaneous PET/MR imaging: A phantom study.

Purpose: Positron emission tomography (PET) imaging of yttrium-90 in the liver post radioembolization has been shown useful for personalized dosimetry calculations and evaluation of extrahepatic deposition. The purpose of this study was to quantify the benefits of several MR-based data correction approaches offered by using a combined PET/MR system to improve Y-90 PET imaging. In particular, the feasibility of motion and partial volume corrections were investigated in a controlled phantom study.

Improving (18)F-Fluoro-D-Glucose-Positron Emission Tomography/Computed Tomography Imaging in Alzheimer's Disease Studies.

The goal was to improve Alzheimer's 2-deoxy-2-(18)F-fluoro-D-glucose ((18)F FDG)-positron emission tomography (PET)/computed tomography (CT) imaging through application of a novel, hybrid Fourier-wavelet windowed Fourier transform (WFT) restoration technique, in order to provide earlier and more accurate clinical results. General Electric Medical Systems downward-looking sonar PET/CT 16 slice system was used to acquire studies. Patient data were acquired according the Alzheimer's disease Neuroimaging Initiative (ADNI) protocol.

Precise fusion of MRI and dual energy 111In WBC/99mTc HDP SPECT/CT in the diabetic foot using companion CT: an example of SPECT/MRI imaging.

Aim: The purpose of our study was to correctly fuse MRI and SPECT ¹¹¹In WBC and ⁹⁹m Tc HDP images using companion CT images. The fused images could be used to assess proper surgical approach in treatment of the diabetic foot.

Methods: Nine patients who had dual energy ¹¹¹In WBC/ ⁹⁹m Tc HDP SPECT/CT and MRI studies within a week were investigated in an ongoing project.

Comparison of MR-based attenuation correction and CT-based attenuation correction of whole-body PET/MR imaging.

Purpose: The objective of this study was to evaluate the performance of the built-in MR-based attenuation correction (MRAC) included in the combined whole-body Ingenuity TF PET/MR scanner and compare it to the performance of CT-based attenuation correction (CTAC) as the gold standard.

Methods: Included in the study were 26 patients who underwent clinical whole-body FDG PET/CT imaging and subsequently PET/MR imaging (mean delay 100 min). Patients were separated into two groups: the alpha group (14 patients) without MR coils during PET/MR imaging and the beta group (12 patients) with MR coils present (neurovascular, spine, cardiac and torso coils).

Quantitative comparison of yttrium-90 (90Y)-microspheres and technetium-99m (99mTc)-macroaggregated albumin SPECT images for planning 90Y therapy of liver cancer.

Yttrium-90 ((90)Y)-microspheres administered via the hepatic artery has been used for the treatment of unresectable primary or metastatic cancer in the liver. Prior to (90)Y therapy, however, the (90)Y administered activity and the percent shunting to lungs must be determined, most commonly by gamma camera imaging of technetium-99m ((99m)Tc)-macroaggregated albumin (MAA). The purpose of the current study was to identify and evaluate an objective measure of the correlation of (90)Y and MAA activity distributions and thus assess the reliability of MAA imaging for evaluation of (90)Y administered activity and tumor and liver radiation doses.

Repeatability of regional myocardial blood flow calculation in 82Rb PET imaging.

Background: We evaluated the repeatability of the calculation of myocardial blood flow (MBF) at rest and pharmacological stress, and calculated the coronary flow reserve (CFR) utilizing 82Rb PET imaging. The aim of the research was to prove high repeatability for global MBF and CFR values and good repeatability for regional MBF and CFR values. The results will have significant impact on cardiac PET imaging in terms of making it more affordable and increasing its use.

Fluoro-deoxy-glucose positron emission tomography for evaluation of indeterminate lung nodules: assigning a probability of malignancy may be preferable to binary readings.

Objective: To assess the diagnostic value of fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) using standard uptake values (SUV) in the differential diagnoses of indeterminate pulmonary nodules. Specifically, we assessed the probability of malignancy for various SUV ranges, and compared the diagnostic efficacy of SUV with and without correction for partial volume effects on the basis of lesion size.

Methods: The FDG-PET scans performed on 158 patients with biopsy-proven pulmonary lesions seen on computed tomography (CT) scan were retrospectively reviewed.

Comparison of 2D, 3D high dose and 3D low dose gated myocardial 82Rb PET imaging.

Background: We compared 2D, 3D high dose (HD) and 3D low dose (LD) gated myocardial Rb-82 PET imaging in 16 normal human studies. The main goal in the paper is to evaluate whether the images obtained by a 3D LD studies are still of comparable clinical quality to the images obtained with the 2D HD or 3D HD studies.

Methods: All 2D and 3D HD studies were performed with 2220 MBq of Rb-82.

Comparison of 18F SPECT with PET in myocardial imaging: a realistic thorax-cardiac phantom study.

Background: Positron emission tomography (PET) imaging with fluorine-18 (18F) Fluorodeoxyglucose (FDG) and flow tracer such as Rubidium-82 (82Rb) is an established method for evaluating an ischemic but viable myocardium. However, the high cost of PET imaging restricts its wider clinical use. Therefore, less expensive 18F FDG single photon emission computed tomography (SPECT) imaging has been considered as an alternative to 18F FDG PET imaging.

Improving 3D PET imaging by restoration: a phantom study.

The main objective of our work is to improve 3D PET imaging. Compared with 2D PET, 3D PET imaging has slightly worse axial resolution and a significantly higher contribution of scatter and randoms, but 3D PET has much better sensitivity than 2D PET imaging. A Jaszczak deluxe phantom was acquired in 3D mode on our GE Advance PET system.

Reducing exposure from 57Co sources during breast lymphoscintigraphy by optimizing energy windows and other suggested enhancements of acquisition and the display of images.

Unlabelled: We set out to measure the reduction in exposure attained by using a weak 57Co sheet source with optimal energy windows.

Methods: Two groups of 10 lymphoscintigraphy studies were analyzed. Group 1 consisted of 10 studies obtained with a stronger source of 57Co, 59 MBq (1.

Comparison of 2-dimensional and 3-dimensional 82Rb myocardial perfusion PET imaging.

Unlabelled: We compared 2-dimensional (2D) and 3-dimensional (3D) (82)Rb PET imaging in 3 different experiments: in a realistic heart-thorax phantom, in a uniformity-resolution phantom, and in 14 healthy volunteers.

Methods: A nonuniform heart-thorax phantom was filled with 111 MBq of (82)Rb injected into the left ventricular (LV) wall. In the LV wall of the cardiac phantom, 3 inserts-1, 2, and 3 cm in diameter-were placed to simulate infarcts.