gamma camera

OBJECTIVE: The aim of this study was to assess the biodistribution and dosimetry of 177Lu-DOTA-trastuzumab in patients with HER2-positive breast carcinoma using whole-body (WB) planar imaging at multiple time points. PATIENTS AND METHODS: This study was a prospective evaluation of HER2-positive metastatic/locally advanced breast carcinoma patients who underwent gamma camera imaging for dosimetry and biodistribution studies by using 177Lu-DOTA-trastuzumab. The standard diagnostic dosimetry protocol was followed, which included cold trastuzumab injection followed by in-house produced 177Lu-DOTA-trastuzumab...

To detect and track structural changes in atomic nuclei, the systematic study of nuclear levels with firm spin-parity assignments is important. While linear polarization measurements have been applied to determine the electromagnetic character of gamma-ray transitions, the applicable range is strongly limited due to the low efficiency of the detection system. The multi-layer Cadmium-Telluride (CdTe) Compton camera can be a state-of-the-art gamma-ray polarimeter for nuclear spectroscopy with the high position sensitivity and the detection efficiency...

BACKGROUND: The dead-time loss reportedly degrades the accuracy of dosimetry using a gamma camera for targeted radionuclide therapy with Lu-177; therefore, the dead-time loss needs to be corrected. However, the correction is challenging. In this study, we propose a novel and simple method to shorten the apparent dead time rather than correcting it through experiments and Monte Carlo simulations. METHODS: An energy window of 208 keV ± 10 % is generally used for the imaging of Lu-177...

In imaging of Yttrium-90 patients treated hepatic primary and metastatic cancers, bremsstrahlung photons produced in a wide energy range is used. However, the image quality depends on acquisition energy window. This research aimed energy window optimization for Yttrium-90 bremsstrahlung imaging and 48 patients with various types of cancer received radioembolization therapy were investigated. Patients were imaged using a GE Healthcare Optima NM/CT 640 series gamma camera system with a medium energy general-purpose (MEGP) collimator and planar images were acquired with 8 different energy windows in the 55-400 keV energy range...

The radiolabeled iron oxide nanoparticles constitute an attractive choice to be used as dual-modality contrast agents (DMCAs) in nuclear medical diagnosis, due to their ability to combine the benefits of two imaging modalities, for instance single photon emission computed tomography (SPECT) with magnetic resonance imaging (MRI). Before the use of any DMCA, the investigation of its plasma extra- and on/intra cellular distribution in peripheral human blood is of paramount importance. Here, we focus on the in vitro investigation of the distribution of 99m Tc-DPD-Fe3 O4 DMCA in donated peripheral human blood (the ligand 2-3-dicarboxypropane-1-1-diphosphonic-acid is denoted as DPD)...

The field of nuclear medicine is entering a new era of gamma-camera technology. Solid-state SPECT/CT systems will gradually replace the thallium-activated sodium-iodide NaI(Tl) systems. This digital technology allows drastic improvements in image quality, radiotracer dose reduction, and procedure efficiency. This pictorial review presents our initial experience on an NM/CT 870 CZT system (GE Healthcare), equipped with dual-head cadmium zinc telluride (CZT) detectors, for I-123 metaiodobenzylguanidine (MIBG) imaging in pediatric neuroblastoma...

BACKGROUNDS: The lung-to-heart ratio (L/H ratio) in myocardial perfusion scintigraphy (MPS) is a useful marker that complements the sensitivity of ischemia detection. However, it requires planar imaging acquired following a separate protocol in addition to single-photon emission computed tomography (SPECT). We developed a novel method for constructing virtual planar image (VPI) from SPECT data. METHODS: Myocardial phantoms using Tl-201 were built with different amounts of radioactivity in the lungs...

BACKGROUND: The solid-state cadmium-zinc-telluride (CZT) gamma camera for myocardial perfusion single-photon emission computed tomography (MPS) has theoretical advantages compared to the conventional gamma camera technique. This includes more sensitive detectors and better energy resolution. We aimed to explore the diagnostic performance of gated MPS with a CZT gamma camera compared to a conventional gamma camera for detection of myocardial infarct (MI) and assessment of left ventricular (LV) volumes and ejection fraction (LVEF), using cardiac magnetic resonance (CMR) as the reference method...

OBJECTIVE: Small-field dosimetry is an ongoing challenge in radiotherapy quality assurance especially for radiosurgery systems such as CyberKnifeTM. The objective of this work is to demonstrate the use of a plastic scintillator imaged with a commercial camera to measure the output factor of a CyberKnife system. The output factor describes the dose on the central axis as a function of collimator size, and is a fundamental part of CyberKnife quality assurance and integral to the data used in the treatment planning system...

BACKGROUND: In image processing for activity quantification, the end goal is to produce a metric that is independent of the measurement geometry. Photon attenuation needs to be accounted for and can be accomplished utilizing spectral information, avoiding the need of additional image acquisitions. The aim of this work is to investigate the feasibility of 177 Lu activity quantification with a small CZT-based hand-held gamma-camera, using such an attenuation correction method. METHODS: A previously presented dual photopeak method, based on the differential attenuation for two photon energies, is adapted for the three photopeaks at 55 keV, 113 keV, and 208 keV for 177 Lu...

BACKGROUND: The purpose of the study was to present the cardiological procedures performed and scintigraphic devices used in Poland in 2019-2021 - based on the results of a nationwide survey. MATERIAL AND METHODS: Forty-three (100%) institutions performing scintigraphic cardiology tests responded to the survey: 29 classic nuclear medicine centers (NM), 4 PET centers, and 10 institutions performing NM and PET examinations. RESULTS: In 2021, 51 SPECT devices (including 5 dedicated cardiocentric semiconductor cameras, 12 SPECT gamma cameras, and 39 hybrid SPECT/CT devices) and 15 PET devices (14 PET/CT and 1 PET/MR) were used for cardiological examinations...

Hadron therapy is a radiotherapy modality which offers a precise energy deposition to the tumors and a dose reduction to healthy tissue as compared to conventional methods. However, methods for real-time monitoring are required to ensure that the radiation dose is deposited on the target. The IRIS group of IFIC-Valencia developed a Compton camera prototype for this purpose, intending to image the Prompt Gammas emitted by the tissue during irradiation. The system detectors are composed of Lanthanum (III) bromide scintillator crystals coupled to silicon photomultipliers...

In advanced driver assistance systems (ADAS) or autonomous vehicle research, acquiring semantic information about the surrounding environment generally relies heavily on camera-based object detection. Image signal processors (ISPs) in cameras are generally tuned for human perception. In most cases, ISP parameters are selected subjectively and the resulting image differs depending on the individual who tuned it. While the installation of cameras on cars started as a means of providing a view of the vehicle's environment to the driver, cameras are increasingly becoming part of safety-critical object detection systems for ADAS...

Glomerular filtration rate (GFR) is the most reliable parameter of renal function. Regarding the complexity of the gold standard inulin clearance, different estimating equations have been developed with CKD-EPI creatinine equation recommended as the most reliable one. In some clinical situations where creatinine based equations might not be valid, alternative methods are needed. Nuclear medicine methods for measuring GFR with 51Cr EDTA and 99mTc DTPA have been widely used for decades. There are different methodologies for the measurement of kidney function with radiopharmaceuticals: urinary clearance, plasma clearance, multiple plasma sampling, slope intercept, single sample plasma equation, slope only, and the gamma camera-based method...

The glomerular filtration rate (GFR) is important for assessing renal function and must be calculated reliably and reproducibly. This study aimed to compare the reliability and accuracy of GFR estimated with 99m-technetium diethylene-triamine-pentaacetate (99mTc-DTPA) versus that calculated from the effective renal plasma flow (ERPF) (GFR is 20% of ERPF) determined by the 99m-technetium ethylene dicysteine (99mTc-EC) technique. Forty-five patients suffering from cancer requiring platinum compound-based chemotherapy or from chronic renal failure were recruited...

PURPOSE: Radiolabeled PSMA-ligands play a major role in today's nuclear medicine. Since approval of [177 Lu]Lu-PSMA-617 for therapy of metastatic prostate cancer, availability of 177 Lu became bottleneck of supply due to the high demand. Recently, a theranostic PSMA-ligand, PSMA-GCK01, was developed which can be labeled either diagnostically with 99m Tc or therapeutically with 188 Re with both nuclides available from well-known generator systems. This novel tracer might aid to overcome aforementioned supply limitations...

Background : The use of 201 Tl in myocardial perfusion single-photon emission computed tomography (SPECT) is predominantly not recommended because of the higher radiation exposure of 201 Tl compared to 99m Tc agent. However, the advent of new gamma cameras with semiconductor detectors has made it possible to reduce the 201 Tl dose and lower radiation exposure. In our hospital, the dose of 201 Tl is adjusted according to the patient's body mass index (BMI), with 50 MBq for BMI<25 and 74 MBq for BMI≥25...

Over-expression of sigma-2 receptor in cancer cells provides an opportunity to develop molecular probes for diagnosis, even for non-receptor specific malignancies like triple negative breast cancers. In this work, a novel sigma-2 receptor ligand [THQ-DTPA] has been synthesized and characterized using 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (THQ) and diethylenetriaminepentaacetic acid (DTPA). The ligand is further chelated with 99m Tc for application as metal based radiotracer [99m Tc-THQ-DTPA]. Radiolabelling with 99m Tc was achieved in an excellent yield of 98...

The purpose of SPECT/CT imaging to be used in dosimetric calculations is to perform accurate attenuation correction by giving the patient the minimum radiation dose. in accordance with ALARA principles (as low as reasonably achievable), it is critical to limit the amount of radiation given to the patient as far as possible in medical fields where radiation therapy is applied. The goal of this study is to determine the optimum kV and mAs values needed to keep the radiation dose that can be given to the patient in CT scans at a minimum level for attenuation correction, as well as to determine the CT-induced radiation doses on patients with different kV and mAs values using an anthropomorphic phantom...

The Dynamic Cardiac SPECT (DC-SPECT) system is being developed at the Massachusetts General Hospital, featuring a static cardio-focus asymmetrical geometry enabling simultaneous high-resolution and high-sensitivity imaging. Among 14 design iterations of the DC-SPECT with varying number of detector heads, system sensitivity and resolution, the version under development features 10 mm FWHM geometrical resolution (without resolution recovery) and 0.07% sensitivity at the FOV center, this is 1.5x resolution gain and 7x sensitivity gain compared to a conventional dual-head gamma camera (0...