Search

Introduction. Exposure to SARS-CoV-2 leads to damage and dysfunction of the microvasculature of the lungs. The development of vasculitis, an increase in the permeability of the vessel wall, changes in the vascular-platelet and coagulation hemostasis, lead to the development of thrombosis / thromboembolism and hemorrhages. Single-photon emission tomography of the lungs is optimal for assessing changes in microcirculation in the lungs of patients with COVID-19 infection, since CT angiography can detect these formidable complications only in the large vessels of the lungs.Оbjective оf the work. To assess changes in the microvasculature of the lungs in patients with the development of postcovid syndrome and to assess the possibilities of single photon emission computed tomography in the diagnosis of thromboembolism, thrombosis and hemorrhages.Material and methods. The data of radiological studies performed in 138 patients in the postcovid period were analyzed, directed for examination to assess changes in blood circulation in the lungs and identify complications of the disease (thromboembolism, thrombosis, hemorrhages).Results. In patients who underwent an infection caused by the SARS-CoV-2 virus in a mild form, we identified changes in microcirculation most characteristic of manifestations of vasculitis and small local blood flow defects close to a triangular shape (microthrombosis), which correlated with an increase in fibrinogen (4.32 ± 0.21 g/L) (rs = 0.97; p = 0.001). Signs of microthrombosis, pulmonary embolism were detected in 35.9% of moderately severe patients who did not receive anticoagulant therapy or was prescribed it on day 10–12 of illness, and in 67.2% of severe and extremely severe patients who received anticoagulant therapy during the illness. Signs of postthromboembolic changes were detected in 16 patients (59.2%) in the late postcovid period, which correlated to a high degree (rs = 0.81; p = 0.03) with an increase in the level of fibrinogen (4.5 ± 1.9 mg/l).Conclusions. The severity of microcirculation disorders in the lungs depends on the severity of the disease and the timing of the postcovid period. Signs of small branch thromboembolism / thrombosis are detected in the early postcovid period. In patients who have undergone COVID-19 with the development of thrombosis, signs of postponed pulmonary embolism are revealed and zones of local pneumosclerosis are formed.

The purpose of this paper is to give an overview of various well known medical image registration techniques with a special focus on registration between anatomical and functional medical images. Examples of anatomical medical images (AMI) are Computer Tomography (CT), Magnetic Resonance Images (MRI), X-ray radiographs and ultrasound etc. whereas Positron Emission Tomography (PET), Single Photon Emission Tomography (SPECT) and fMRI are examples of functional medical images (FMI). Irrespective of such types (AMI or FMI), every case can be considered as a medical imaging modality. All these modalities are widely used by clinicians to study the structure/functionality of human body parts for diagnosis and treatment. It is frequently required to combine PET/SPECT with CT/MRI to simultaneous study the metabolic and molecular information received through PET/SPECT with fine anatomical details observed by CT/MRI. This concurrent study will help in the diagnosis and localization of many diseases like cancer, blockage in coronary arteries and brain-related diseases like Parkinson, Alzheimer etc. Further, in many cases, clinicians are required to co-register one or more anatomical images with functional images, for example, ultrasound-guided biopsy fused with PET and MRI. This registration can be done either at the hardware level or at the software level. The introduction of integrated PET-CT machine increases the acceptability of hardware-based registration systems as compared to software-based methods among the medics. One possible reason for this is the lack of validation of results achieved through software-based registration methods. On the other hand, software-based registration methods also have many advantages over the hardware-based registration systems like lesser exposure to radiation and no need for new investment on hardware etc. In this paper, both the methods with their merits and demerits are discussed in detail.

In vivo imaging has a potential to bring innovation to translational toxicology for drug discovery. This includes magnetic resonance imaging, positron emission tomography (PET), single photon emission tomography, and computed tomography. The utility of imaging comes from its capacity to provide minimally invasive biomarkers for safety profiling and decision-making in drug discovery. Nonspecific biomarkers, such as magnetic resonance imaging relaxometry, computed tomography density, or PET 18F-fluoro-2-deoxy- d -glucose are better suited for preclinical general toxicology and clinical monitoring, while specific ones, such as most of PET and single photon emission tomography ligands, are better suited to clarify mechanisms of toxicity or unwanted target engagement. However, the use of these biomarkers is sporadic and governed by scientific interest and availability rather than its utility. A systematic approach is needed to qualify these biomarkers with regulatory authorities so translational imaging could be incorporated into drug development and its unique potential translated into safer and cheaper medicines.

Background Osteoblastoma (OB) is an intermediate lesion, which makes the accurate preoperative diagnosis very important. 99mTc-methylene diphosphonate (99mTc-MDP) bone scan and SPECT/CT imaging were evaluated for their diagnostic value in spinal OB. Methods This study was a retrospective analysis of patients with spinal OB lesions confirmed by pathology and diagnosed with bone scan and SPECT/CT for preoperative diagnosis from January 2008 to December 2018. The uptake levels of OB on planar bone scan were divided into low, medium, and high groups by visual assessment referring to the uptake of the normal rib, spine, and bladder. X-ray, CT, MRI, bone scan, and SPECT/CT imaging of the patients were analyzed for characteristics summary. Results Twenty-five patients were diagnosed for spinal OB (17 males and 8 females with a proportion of 2.1:1), and the average age was 26.8 ± 10.8 years (range 5~59). There were 8 lesions located in the cervical, 6 in the thoracic, and 11 in the lumbar vertebrae. Twenty-four lesions involved posterior elements, especially the pedicles (14/25). Symptoms were predominantly painful with a duration of 18.3 ± 13.9 months (range 0.5~60 months). The lesion size ranged from 9 to 35 mm. All the lesions were low to high uptake in the planar bone scan, and the percentages of low to high levels were 1 (4%), 8 (32%), and 16 (64%) cases. Conclusions Spinal OB mainly involved the posterior area, and elderly patients should be considered as well. SPECT/CT combined the characteristics of bone uptake and anatomical features of bone tumors, proving its one-in-all diagnostic value for spinal OB and other osteogenic tumors.

The aim of this paper is to present the most relevant clinical applications of positron emission tomography/computed tomography, scintigraphy and single photon emission tomography with different radiotracers allowing to visualize e.g. glucose metabolism, amino acids metabolism, receptor density or inflammation and infections in diabetology.

Widely established compared to myocardial perfusion imaging, cardiac autonomous nervous system (CANS) assessment by radiopharmaceutical means is of potential use especially to arrhythmogenic diseases not correlated with anatomic or functional alterations revealed by classical imaging techniques. Molecular imaging of both pre- and postsynaptic functions of the autonomous nervous system is currently feasible, since single photon emission tomography (SPECT) and positron emission tomography (PET) have the ability to reveal the insights of molecular pathophysiology depicting both sympathetic and parasympathetic imbalance in discrete heart pathologies. This review provides not only a brief presentation of radiopharmaceuticals used for non-invasive CANS imaging in the case of ventricular arrhythmias, but also a current update on ventricular tachycardias, cardiomyopathies, Brugada and Long QT syndrome literature.

Measurement of radionuclides biodistribution in post-radioembolization 90Y SIRT is a part of treatment evaluation, in which the assessment of biodistribution is used to evaluate the possible extrahepatic presence and the absorbed dose estimation for the tumor cells, healthy liver cells, and critical organs. As the dose-response analysis is performed based on this evaluation, the biodistribution measurement coming from post-imaging modality has a crucial role in achieving these goals. The two devices, Single Photon Emission Tomography (SPECT) and Positron Emission Tomography are discussed in some aspects, including the quality of quantitative images, performance characteristics, and absorbed dose considerations.

"Neuroimaging plays a vital role in the diagnosis of primary and secondary vasculitic disorders. There multiple neuroimaging options available to accurately describe the underlying clinical deficits of involved cases. Noninvasive neuroimaging modalities provide less risk and when interdigitated, form the basis for a more conclusive understanding of the disease process. There are instances in which invasive cerebral angiography may be needed to image the intricate and at times, small involved vessels. Neuroradiologists should be included in the multidisciplinary team of physicians caring for patients with vasculitides and in research to provide more sensitive and safe modalities for accurate diagnosis."

Since the foundation of the Korean Society of Nuclear Medicine in 1961, clinical nuclear oncology has been a major part of clinical nuclear medicine in Korea. There are several important events for the development of clinical nuclear oncology in Korea. First, a scintillating type gamma camera was adopted in 1969, which enabled to perform modern oncological gamma imaging. Second, Tc-99 m generator was imported to Korea since 1979, which promoted the wide clinical use of gamma camera imaging by using various kinds of Tc-99 m labeled radiopharmaceuticals. Third, a gamma camera with single photon emission tomography (SPECT) capability was first installed in 1980, which has been used for various kinds of tumor SPECT imaging. Fourth, in 1994, clinical positron emission tomography (PET) scanner and cyclotron with a production of F-18 fluorodeoxyglucose were first installed in Korea. Fifth, Korean Board of Nuclear Medicine was established in 1995, which contributed in the education and manpower training of dedicated nuclear medicine physicians in Korea. Finally, an integrated PET/CT scanner was first installed in 2002. Since that, PET/CT imaging has been a major imaging tool in clinical nuclear oncology in Korea. In this review, a brief history of clinical nuclear oncology in Korea is described.

In nuclear medicine, the imaging process used to diagnose diseases and to examine the functions of organs is carried out with radiopharmaceuticals containing radioisotope. In this study, the amount of external radiation emitted from bone scintigraphy patients who were given 99mTc-MDP kit was examined. The measurements have been performed using FLUKE Victoreen ASM 990 portable detector at Nuclear Medicine Department Medicine Faculty in Tokat Gaziosmanpasa University. The external dose rate values have been measured at 0.50 m, 1.0 m, 2.0 m and 3.0 m away from the patient considered as the source of radiation. All measurements have been taken within approximately one hour and 10 minutes at 10 minutes intervals after injection of the pharmaceutical. In this study, the highest external dose rate value is measured 13.81 μSv h-1 from 0.50 m distance after 30 minutes from the radiopharmaceutical injection and the lowest external dose rate value 1.53 μSv h-1 is obtained from 3.0 m distance after 60 minutes. Then, dose rate values per unit activity were calculated and the highest value was found as 20.57 μSv h-1 GBq-1 30 minutes after injection at 0.50 m. The results obtained were compared with other studies in the literature.

Diagnosis of pulmonary embolism using V/P-SPECT may include the application of advanced image-processing techniques to identify V/P-mismatches. Aim of this study was to evaluate the benefit in clinical decision making in the diagnosis of pulmonary embolism.by whether adding to conventional reading a software that automatically calculates and visualizes the ventilation/perfusion-quotient pixel by pixel. 63 consecutive patients with a clinical suspicion of PE who underwent V/P-SPECT were included in this retrospective study. Images were randomly ordered both for standard as well as for software-assisted reading using V/P-quotients. Studies were read independently by 2 experienced and 2 inexperienced raters. Diagnostic performance and observer agreement of all readers and both reading methods were determined. Expert observers consistently achieved a high diagnostic accuracy both in conventional as well as in software-assisted reporting (sensitivity: 0.94 vs. 0.94, specificity: 0.96 vs. 0.97, LR Benefit from a software-tool that calculates V/P-ratio automatically is only small when used by experienced physicians If inexperienced readers use the software, the diagnostic accuracy increases. Images generated by automated calculation of V/P-mismatches are easy to read and their use might help to standardize and objectify interpretation of V/P-SPECT in the diagnosis of PE.ZIEL: Die Diagnostik der Lungenembolie mittels V/P-SPECT kann durch bildverarbeitende Techniken zur Identifizierung von V/P-Mismatches unterstützt werden. Ziel dieser Studie war es zu beurteilen, ob die Nutzung einer semiautomatisierten Software, die den Ventilations-/Perfusions-Quotienten berechnet und visualisiert, einen Zusatznutzen hinsichtlich der diagnostischen Genauigkeit bringt. 63 konsekutive Patienten, die eine V/P-SPECT wegen des klinischen Verdachts einer PE erhielten, wurden in die retrospektive Studie eingeschlossen. Die Datensätze wurden randomisiert und von je 2 erfahrenen und unerfahrenen Befundern nach konventioneller Methode sowie unter zusätzlicher Anwendung des V/P-Quotienten befundet. Die diagnostische Performance und das Maß der Übereinstimmung aller 4 Befunder wurde für beide Befundungsmethoden verglichen. Erfahrene Befunder erreichten eine hohe Genauigkeit in der Befundung, sowohl mittels der konventionellen Methode als auch unter zusätzlicher Nutzung des V/P-Quotienten (Sensitivität: 0,94 vs. 0,94; Spezifität: 0,96 vs. 0,97; LR Erfahrene Ärzte profitieren nicht von der zusätzlichen Nutzung des V/P-Quotienten. Angewendet durch unerfahrene Befunder erhöht sich hingegen die diagnostische Genauigkeit. Die Bilder des V/P-Quotienten sind einfach zu interpretieren und können helfen, die Interpretation der V/P-SPECT bei der Diagnose der PE zu standardisieren und zu objektivieren.

This review describes the development of single-photon emission tomography (SPECT) in the Copenhagen area under the leadership of the internationally renown scientist, Niels A. Lassen, and the history leading up to construction of the tomograph. Measurements of global cerebral blood flow (CBF) in the 1940s and 1950s were performed by Kety & Schmidt and Lassen & Munck. Determination of regional cerebral blood flow (rCBF) by intra-arterial injection of 133 Xe and measurement with a 254-multicrystal scintillation detector and a computer system was a major step forward in the study of physiology and pathophysiology of cortical cerebral blood flow. Tomography with radioisotope ligands, including non-invasive administration, was advanced in different centres during the 1970s. An emission tomograph, the Tomomatic 64, was developed as a result of a multidisciplinary Danish and international collaboration. It was the first emission tomograph to provide dynamic data that could produce cross-sectional rCBF images. The present description of the construction and function of the Tomomatic 64 includes comparison with other contemporary and later brain-dedicated SPECT systems. Basic and clinical application of the Tomomatic 64 in Copenhagen resulted in several hundred important scientific publications and improved diagnostics for patients with a variety of neurological disorders. It is concluded that the development of the Tomomatic 64 was a major step forward in the study and examination of rCBF and brain function related to several brain disorders, in addition to vascular diseases.

Cardiac and vascular infection is an arising cause of mortality and morbidity in the adult population. Diagnosis based on culture and anatomic imaging are frequently inconclusive. Radiolabeled leucocyte scintigraphy plays a useful role in the diagnosis and management of these serious infectious conditions. In this paper, we present an update on the diagnostic performance of single- photon emission tomographic (SPECT) techniques using different radionuclides in the management of patients with cardiac and vascular infections. We performed a thorough search of recent literature on the topic. We present a discussion on the clinical utility of different SPECT tracers in cardiac and vascular infections, including infective endocarditis, cardiac implantable electronic device (CIED) infections, left ventricular assist device infection, and vascular graft infection. Radionuclide technique using SPECT tracers is a useful imaging modality in the diagnosis of cardiac infection. Among the different SPECT tracers for infection imaging, radiolabeled leucocyte scintigraphy is currently the most useful tool in the diagnosis and management of patients with suspected cardiac and vascular infection. Radiolabeled leucocyte scintigraphy has a high specificity, a result of the ability of the leucocytes to accumulate as sites of pyogenic infection but not at sites of sterile inflammation such as seen in the early post-operative period or in response to the presence of a prosthetic cardiac or vascular material. Limited experience with radiotracers for in vivo labelling of leucocytes such as 99mTc-sulesomab and 99mTc-besilesomab show acceptable diagnostic performance without the need for the tedious process of ex-vivo labeling. 67Ga scintigraphy used to be popular for cardiac and vascular infection imaging. Its use has run out of favor following the availability of more effective molecular imaging methods. SPECT techniques with radiolabeled leucocyte scintigraphy has a high diagnostic performance in the evaluation of patients with suspected cardiac or vascular infection. It is able to confirm or reject the presence of infection when results of anatomic imaging or culture remain inconclusive. Its diagnostic performance is not compromised by sterile inflammation occurring in the early post-operative period or in response to implanted prosthetic materials.

Objectives: This was a prospective, single-center study designed to assess the prognostic value of the hybrid technique of single photon emission tomography and computed tomography with the...

Aim. To assess efficacy and safety of inclusion of physical trainings to the program of patients prehabilitation before coronary bypass (CBG) on-pump, from the perspective of cardioprotection. Material and methods. Totally, 38 patients included, randomized to 2 group depending on prehabilitation program. Group 1 patients (n=20, mean age 57,9±7,2 y. o.) at the stage of prehabilitation, underwent serial physical trainings of high intensity; in group 2 (n=18, mean age 60,4±7,01 y. o.) there were none. Evaluation of the target parameters of myocardial perfusion was done before the training and in post-operation period with single photon emission tomography (SPECT). Results. In the group with included exercises, during post-surgery period there was significantly higher level of radiopharmacological marker capture comparing to nontrained group in some basal segments (74,9±3,98% and 70,3±7,40%, respectively, р=0,04), middle (86,7±5,24% and 79,6±10,43%, resp., р=0,03) and apical (85,8±5,03% and 79,0±8,67%, resp., р=0,02) portions of myocardium, by SPECT. Integral value of the stress-induced temporary ischemia (SDS) after CBG in training group was significantly lower than in non-training group (0 and 0,9±0,53 pts., resp., р=0,04). Dynamics analysis of the parameters of myocardial perfusion demonstrated significant decrease of the parameter characterizing perfusion defect with adenosin load (SSS) (р=0,013), and SDS (р=0,018) in the group of exercises after operation comparing to pre-operational values. In non-training group the dynamics was nonsignificant. Conclusion. According to the data obtained, inclusion of physical trainings of high intensity to the program of prehabilitation of patients before CBG leads to improvement of myocardial perfusion parameters in post-operation period, that possibly optimizes the outcomes of surgery.

Background and purpose Computer-based analysis of Dopamine transporter imaging (DaTscan) can aid in image interpretation. In this study, we examined the distribution of putamen-to-caudate ratios (PCRs) obtained by using a clinically available semiquantification method. Methods Medical records of 32 patients (M:16) with a diagnosis of Parkinson's disease (PD) (n = 22) or Parkinson's plus syndromes (PPS) (n = 10) based on clinical follow-up, were retrospectively reviewed. Single photon emission tomography (SPECT) imaging was performed 4 hours after intravenous injection of 3-5 mCi [I-123]-ioflupane. Semiquantitative evaluation using DaTQUANT software was performed. Utility of PCR with a cutoff of .7 and .8 in the diagnosis of nigrostriatal degeneration was assessed. PD and PPS groups based on clinical assessment and caudate-to-background ratio (CBR) were assessed separately. Results Minimum PCR for both hemispheres was .74 ± .09 (Mean ± SD, range: .58-.89), with 65.63% patients (21/32) having PCR > .7. Mean PCR in mild nigrostriatal degeneration was .77 ± .08 (range: .62-.89) and in advanced nigrostriatal degeneration was .73 ± .09 (range: .58-.89). Mean PCR in PD group was .73 ± .09 (range: .58-.89) and in PPS group was .75 ± .10 (range: .61-.88). Conclusions Although PCR can intrinsically be a useful indication of disease, this ratio obtained in our analysis by using one of the clinically available automatic semiquantitative methods has large variability and might not be a reliable numeric marker in interpretation of [I-123]ioflupane studies. This may be due to difficulty in separating caudate from putamen on SPECT images, as well as the nonuniform decreased Ioflupane uptake in both putamen and caudate.

Objective: To determine whether there were differences in clinical outcomes for ioflupane I123 injection (DaTscan) and single photon emission tomography consistent with early Parkinson’s disease (P...

OBJECTIVE Cadmium-zinc-telluride detectors enable shorter acquisition durations in myocardial perfusion imaging (MPI), but the time interval of sequential scanning is still unchanged in clinical practice. We designed a very rapid 1-day protocol of MPI using cadmium-zinc-telluride single-photon emission tomography and evaluated the optimal dose ratio between two scanning acquisitions by means of simulations and phantom experiments. METHODS We intended to perform a 1-day MPI within 140 min and simulate radioactivities in the second scan under various injected dose ratios. To apply this, a cardiac phantom was scanned with various radioactivities and scans were compared with a reference scan with the ideal tracer concentrations. RESULTS In the stress-first protocol, the dose ratio 1 : 5 was enough to show the same regional percentage uptake compared with the reference. However, in the rest-first protocol, the regional percentage uptakes were higher than those of the reference image even with a 1 : 6 dose ratio. CONCLUSION The injected dose ratio 1 : 5 is optimal in a stress-first rapid 1-day protocol. The rest-first protocol is not appropriate because a dose ratio greater than 1 : 6 is required to withdraw shine-through artifacts.

OBJECTIVES Sentinel lymph node (SLN) mapping is currently a routine technique in breast cancer management and preoperative scintigraphic imaging plays a crucial role in the process of SLN detection. The guidelines recommend performing planar acquisition and optional single-photon emission tomography/computed tomography (SPECT/CT) imaging. The aim of this study was to verify whether routine performing of SPECT/CT in addition to planar imaging increases the sensitivity of SLN detection in patients with early-stage breast cancer. The secondary aims were to compare radionuclide SLN imaging with intraoperative SLN detection and identify clinical and histopathological factors affecting the SLN detection rate. MATERIALS AND METHODS A total of 153 early-stage breast cancer patients underwent lymph node scintigraphy in the years 2007-2013. Breast cancer patients with staging T1-2N0M0 were included. Planar and SPECT/CT lymphoscintigraphy were performed on the day before the surgery. The data on presence or absence of SLN, their number and localization were recorded for both methods and compared with each other as well as with intraoperative blue dye staining and histopathological findings. RESULTS SPECT/CT identified SLN in 119/153 and planar scintigraphy in 114/153 patients. Identification rates were 77.7 and 74.5%, respectively. Intraoperative lymph node assessment identified SLN in 76/126 cases with an identification rate of 60.3%. Identification rates for second echelon lymph node were 34.6% for hybrid imaging and 21.2% for planar scintigraphy. Statistical analysis did not yield a significant difference in diagnostic accuracy between these methods; however, the Wilcoxon signed-rank test showed that SPECT/CT significantly increases SLN identification rate compared with planar scintigraphy and intraoperative detection. Histopathological examination of excised SLN showed that 22 nodes were metastatic. SPECT/CT visualized all of these, whereas planar imaging and intraoperative lymph node detection procedure visualized 19 and 18, respectively. No clinical and histopathological factors affecting SLN detection rate were identified. CONCLUSION Hybrid SPECT/CT lymphatic mapping yields a high SLN detection rate in patients with early-stage breast cancer and provides lymph node localization details. It identifies more SLN than planar imaging and intraoperative SLN detection. However, its limited superiority over the remaining two methods does not support its routine use for SLN localization. We suggest using SPECT/CT for SLN detection in case of equivocal planar imaging results.

Background It was the primary purpose of our study to evaluate the inter- and intra-observer reliability of a standardized SPECT/CT algorithm for evaluating patients with painful primary total hip arthroplasty (THA). The secondary purpose was a comparison of semi-quantitative and 3D volumetric quantification method for assessment of bone tracer uptake (BTU) in those patients. Methods A novel SPECT/CT localization scheme consisting of 14 femoral and 4 acetabular regions on standardized axial and coronal slices was introduced and evaluated in terms of inter- and intra-observer reliability in 37 consecutive patients with hip pain after THA. BTU for each anatomical region was assessed semi-quantitatively using a color-coded Likert type scale (0-10) and volumetrically quantified using a validated software. Two observers interpreted the SPECT/CT findings in all patients two times with six weeks interval between interpretations in random order. Semi-quantitative and quantitative measurements were compared in terms of reliability. In addition, the values were correlated using Pearson`s correlation. A factorial cluster analysis of BTU was performed to identify clinically relevant regions, which should be grouped and analysed together. Results The localization scheme showed high inter- and intra-observer reliabilities for all femoral and acetabular regions independent of the measurement method used (semiquantitative versus 3D volumetric quantitative measurements). A high to moderate correlation between both measurement methods was shown for the distal femur, the proximal femur and the acetabular cup. The factorial cluster analysis showed that the anatomical regions might be summarized into three distinct anatomical regions. These were the proximal femur, the distal femur and the acetabular cup region. Conclusions The SPECT/CT algorithm for assessment of patients with pain after THA is highly reliable independent from the measurement method used. Three clinically relevant anatomical regions (proximal femoral, distal femoral, acetabular) were identified.

Die Arbeit gibt einen Uberblick uber den Einsatz der PET- und SPECT-Bildgebung des pra- und postsynaptischen dopaminergen Systems bei klinisch wichtigen Bewegungsstorungen. Die typischen Untersuchungsbefunde bei neurodegenerativen Parkinson-Syndromen (idiopathisch und nicht-idiopathisch), symptomatischen Parkinson-Syndromen und wichtigen Differenzialdiagnosen wie vaskulares Parkinson-Syndrom und essenziellem Tremor werden detailliert beschrieben. Neben der Zusammenstellung in der Literatur publizierter Erkenntnisse wird besonders auf den klinisch praktischen Stellenwert der Methoden eingegangen. Dazu werden die diagnostische Aussagekraft und Limitationen der Methoden bewertet und die in Leitlinien festgehaltenen Einsatzbereiche angesprochen.

Introduction: This study aims to explore clinical values and possibilities of heart artifact elimination for patients who underwent SPECT myocardial perfusion scintigraphy. The main focus is on nuclear medicine technologists and their knowlodge of the new technologies developed in nuclear cardiology. Methods: A qualitative descriptive study, review article has been performed for this research. Pubmed, Web of Science, and Embase were searched using a predefined electronic search strategy. Eighteen studies were deemed eligible for this systematic review. Results: Based on the literature we found average age for the patients with coronary artery disease is 59.69 years for women and 57.39 yeras for men. False positive findings, blurred images, respiratory artifacts and sinogram and linogram interruption is very often, especially with patients with irregular breathing cycles, fear of the reasults, anxiety and patients with high BMI. Many studies performed on phantoms or on patients suggest image artifacts can be reduced or even eliminated with the new scanning methodology, software application upgrade, and with right nuclear medicine technologist education. Conclusion: Coronary artery disease can affect men and women equally so the best diagnostic modality is essential for adequate treatment. Interruption of sinogram or linogram, truncation of the heart and blurred image is the first sign artifact of the image. Essential and the first step of every cardiac proccesing software is sinogram and linogram inspection combined with motion correction evaluation of the raw images. New technologies can improve image quality which can increase sensitivity and specificy of myocardial perfusion scintigraphy in all patients.

Radiomics is a rapidly evolving field of research concerned with the extraction of quantitative metrics-the so-called radiomic features-within medical images. Radiomic features capture tissue and lesion characteristics such as heterogeneity and shape and may, alone or in combination with demographic, histologic, genomic, or proteomic data, be used for clinical problem solving. The goal of this continuing education article is to provide an introduction to the field, covering the basic radiomics workflow: feature calculation and selection, dimensionality reduction, and data processing. Potential clinical applications in nuclear medicine that include PET radiomics-based prediction of treatment response and survival will be discussed. Current limitations of radiomics, such as sensitivity to acquisition parameter variations, and common pitfalls will also be covered.

The aim of this work was to implement an automatic application (AA) for the quantification of the striatum transaxial slices based on [123I]FP-CIT SPECT (Single Photon Emission Tomography) images.A sample of 68 subjects with and without pathology was collected from the nuclear medicine department of the Hospital Particular de Almada.In order to compare the striatum specific uptake ratios (SUR), a semi-automatic application (SAA) was also developed allowing manual adjustments by a specialist operator. The obtained results were compared with the DaTSCAN® V4 application, from General Electric Healthcare. The experimental results based on SUR demonstrate that the AA can successfully discriminate the healthy patients from the pathological subjects. Additionally, a strong correlation was verified between the AA and the semi-automatic methods (DaTSCAN® V4 and the SAA). These methods also evidence intra and inter-operator variability, suppressed by the AA.The proposed methodology for segmentation and quantification of the striatum transaxial images obtained by [123I]FP-CIT SPECT demonstrated that the developed application can accurately complement the visual analysis, requiring future optimization.

Aphasic status epilepticus (ASE) is unusual and has clinical characteristics similar to those of other disorders. Herein, we report 3 cases of ASE. A left-handed man (patient 1) showed continuous aphasia after the administration of flumazenil. He had underlying alcoholic liver cirrhosis and traumatic brain lesions in the right hemisphere. Electroencephalography (EEG) revealed periodic epileptiform discharges in the right frontotemporal area, which were intervened by rhythmic activity with spatiotemporal evolutions. A right-handed woman (patient 2) showed recurrent aphasia. Blood tests revealed a high blood glucose level (546 mg/dL) and high serum osmolality (309 mMol/L). Her EEG showed rhythmic activity in the left frontotemporal area with spatiotemporal evolutions on a normal background rhythm. She became seizure-free after the administration of an antiepileptic drug and strict glucose regulation. A right-handed woman (patient 3) developed subacute aphasia a week before hospital admission. She had a gradual decline of cognition 1 year before. Her EEG showed intermittent quasi-rhythmic fast activity in the frontotemporal area bilaterally, with fluctuating frequency and amplitude. The patient became seizure-free after the administration of an antiepileptic drug. Brain single-photon emission tomography performed after seizure control showed decreased perfusion in the left frontotemporal area. After discharge, her cognitive function gradually declined to a severe state of dementia. ASE can be caused by diverse etiologies; it is usually caused by cerebral lesions and less frequently by non-lesional etiologies or degenerative disorders. Adequate treatment of underlying disorders and seizures is critical for curing the symptoms of ASE.

a Department of Cardiology, General Hospital Center, Chambery, France b Department of Radiology, University Hospital, Grenoble, France c Department of Nuclear Medicine, General Hospital Center, Chambery, France d INSERM U1039, Bioclinic Radiopharmaceutics Laboratory, Joseph Fourier University, Grenoble, France e Department of Nuclear Medicine, University Hospital, Grenoble, France f Department of Cardiology, University Hospital, Grenoble, France

Purpose To prospectively evaluate the clinical utility of xSPECT/CT Bone, a new reconstruction algorithm for single photon emission tomography (SPECT), and compare it with standard SPECT/CT reconstruction. Methods Sequential reporting of SPECT/CT followed by xSPECT/CT images in 200 sequential cases commencing August 2015. Differences between the initial SPECT/CT and the final report (after xSPECT/CT reconstruction) were documented and analysed. 12–18 months after the initial study follow-up, clinical data was sought from a subset of cases in which xSPECT/CT changed the primary diagnosis and imaging correlation undertaken in all patients who subsequently had MRI or CT scans of the same region. Results A majority of the 200 cases were related to assessment of musculoskeletal complaints. The final (scan) diagnosis was changed after reviewing the xSPECT/CT images in 40 (20%) of cases. The reporting physician (Iain Duncan) assessed that the xSPECT/CT had provided more diagnostic information in 71% of cases. A total of 470 additional lesions were found, equivalent to 2.4 lesions per case. In 33 cases of imaging follow-up there was a high degree of correlation with bone scan findings and xSPECT correlated better than SPECT in regard to detailed findings. In only 15/40 cases of diagnostic change could the outcome be verified and in 12/15 the xSPECT/CT revised diagnosis was confirmed. Conclusions In this observational evaluation xSPECT/CT Bone reconstruction offers identifiable imaging improvements over standard SPECT/CT reconstruction algorithms. xSPECT/CT Bone provides an improvement in diagnostic confidence and identifies a greater number of lesions.

Clinical imaging modalities have reached a prominent role in medical diagnosis and patient management in the last decades. Different image methodologies as Positron Emission Tomography, Single Photon Emission Tomography, X-Rays, or Magnetic Resonance Imaging are in continuous evolution to satisfy the increasing demands of current medical diagnosis. Progress in these methodologies has been favored by the parallel development of increasingly more powerful contrast agents. These are molecules that enhance the intrinsic contrast of the images in the tissues where they accumulate, revealing noninvasively the presence of characteristic molecular targets or differential physiopathological microenvironments. The contrast agent field is currently moving to improve the performance of these molecules by incorporating the advantages that modern nanotechnology offers. These include, mainly, the possibilities to combine imaging and therapeutic capabilities over the same theranostic platform or improve the targeting efficiency in vivo by molecular engineering of the nanostructures. In this review, we provide an introduction to multimodal imaging methods in biomedicine, the sub-nanometric imaging agents previously used and the development of advanced multimodal and theranostic imaging agents based in nanotechnology. We conclude providing some illustrative examples from our own laboratories, including recent progress in theranostic formulations of magnetoliposomes containing ω-3 poly-unsaturated fatty acids to treat inflammatory diseases, or the use of stealth liposomes engineered with a pH-sensitive nanovalve to release their cargo specifically in the acidic extracellular pH microenvironment of tumors.

Single photon emission tomography (SPECT) of the brain was studied in 22 children with primary autism with varying degrees of severity. Fifteen children had no perfusion abnormalities on SPECT imaging. Of the remaining seven, decreased perfusion in the left frontoparietal cortex was seen in three, and in the left inferior and medial frontal cortex in two children. No correlation could be found between SPECT, electroencephalography, and magnetic resonance imaging findings. Our findings are similar to those previously reported in some studies, and present areas of further inquiry regarding therapeutic intervention or diagnosis.

The objective of this study was to assess the radiation exposure of the investigators' hand during free-hand single photon emission tomography/ultrasound ((99m)TcO4-fhSPECT/US) of the thyroid. Conventional dosimetry by rings with thermoluminescent detectors (TLDs) was performed in 32 patients (Group A), followed by TLD-chipstrate dosimetry in further 20 patients (Group B). In both the groups, the ambient dose rate was measured by dose rate meter (DRM). The applied activity was in the range of 60-80 MBq (99m)TcO4. In Group A, the exposure per investigation was 7.53 µSv (calculated average) by ring dosimetry and 9.02±5.64 µSv by DRM; in Group B, 10.93 and 9.51 ± 1.76 µSv, respectively. Based on estimated 1224 yearly thyroid investigations per nuclear medicine specialist in Germany, the estimated cumulative yearly exposure of the hand was 11.32 mSv. The hand exposure during a thyroid (99m)TcO4-fhSPECT/US of 20-min duration proved modest and comparable with different methods. Yearly examinations in excess of 1000 per investigator are not expected to add a relevant cumulative risk.

Since the 1970s, a number of neuroimaging studies of electroconvulsive therapy (ECT) have been conducted to elucidate the working action of this highly efficacious treatment modality. The technologies used are single photon emission tomography, positron emission tomography, magnetic resonance imaging, magnetic resonance spectroscopy, and quantitative electroencephalography.A PubMed literature search with focus on clinical studies was made from the inception of the database until December 2013 using the search terms electroconvulsive therapy and neuroimaging.Early methods allowing only identification of global changes of cerebral blood flow and cerebral metabolism show considerable ictal increases of these measures, which normalize during the postictal period. Later methodological developments have given access to measurements of minute activity changes in localized cortical and subcortical areas of the brain and have revealed differences in neurophysiology and metabolism between the hyperactive ictal state and the restorative interictal/postictal periods. Recent magnetic resonance imaging studies seem to pave way for new insights into ECT's effects on increased connectivity in the brain during depression.The existing data reveal considerable variations among studies and therefore do not yet allow the formulation of a unified hypothesis for the mechanism of ECT. The rapid developments in imaging technology, however, hold promises for further elucidation of the mode of action of ECT.

The annual frequency of nuclear medicine examinations is increasing worldwide. This is partly a consequence of the recently introduced single photon emission tomography, combined with computed tomography, and positron emission tomography, combined with computed tomography, techniques, which combine functional, metabolic and morphological information important for the diagnosis of many diseases. However, since the effective radiation dose is the sum of the dose of two components, the hybrid examinations result in increased patient exposure. Accordingly, their justification becomes mandatory. It starts with their clinical importance-the opportunity to resolve a clinical problem decisive for patients' management. Knowledge of the indications, contraindications and the examinations' limitations is the responsibility of the nuclear medicine physician, as well as the choice of the most adequate examination and protocol. In conclusion, the cost and the accessibility of the examinations should not be the principal consideration as opposed to the diagnostic value and the exposure. Flexible protocols and algorithms should be used for hybrid nuclear medicine examinations.

Measurements of cerebral blood flow (CBF) show large variability among healthy subjects. The aim of the present study was to investigate the relative effect of established factors influencing CBF on the variability of resting CBF. We retrospectively analyzed spontaneous variability in 430 CBF measurements acquired in 152 healthy, young subjects using 133Xe single-photon emission computed tomography. Cerebral blood flow was correlated positively with both end-tidal expiratory PCO2 (PETCO2) and female gender and inversely with hematocrit (Hct). Between- and within-subject CO2 reactivity was not significantly different. Including PETCO2, Hct and gender in the model reduced between-subject and within-subject variance by 14% and 13.5%, respectively. Withinsubject variability was mainly influenced by PETCO2 and between-subject variability mostly by Hct, whereas gender appeared to be of little added value when Hct was also accounted for. The present study confirms large between-subject variability in CBF measurements and that gender, Hct, and PETCO2 explain only a small part of this variability. This implies that a large fraction of CBF variability may be due to unknown factors such as differences in neuron density or metabolism that could be subject for further studies.

OBJECTIVES In-111-DTPA-octreotide (OctreoScan) is still pivotal for neuroendocrine tumor imaging, despite the introduction of Ga-68-octreotide tracers. Low-dose computed tomography (LDCT) assists in the localization of SPECT findings but often results in uncertain interpretation. This retrospective study evaluates the impact of coregistration of In-111-DTPA-octreotide SPECT/LDCT with diagnostic CT on interpretation. METHODS Thirty-five consecutive studies, in which coregistration was performed because of uncertain interpretation, were evaluated. Presence of somatostatin receptors was categorized retrospectively as definitely positive, probably positive, probably negative, or definitely negative with and without rigid registration with diagnostic CT, and possible added value of coregistration was evaluated. RESULTS Coregistration was performed in 35 studies. However, on subsequent reading, 4 SPECT/CTs yielded definite results and were omitted. Coregistration was helpful in 30 of the remaining 31 cases, changing reading to definitely positive (7) or to definitely negative (23). In 13 of the 23 cases, diagnosis changed from probably positive to definitely negative. Coregistration contributed in 42 of 48 sites, with greatest benefit in the liver (13/14), pancreas (10/10), and lymph nodes (6/6). CONCLUSIONS Coregistration is becoming increasingly easier and may be utilized when SPECT/LDCT is inconclusive.

The term Lewy body diseases (LBDs) refers to a subset of neurodegenerative disorders that share the accumulation of the so-called Lewy bodies (LB) including: Parkinson’s disease (PD), dementia with Lewy bodies (DLB), and PD later characterized by the occurrence of dementia (PDD). Moreover, multiple system atrophy (MSA) and idiopatic Rem Sleeping behaviour disorders (RBD) complete the group of synucleinopathies and have also common symptoms with respect to LBDs. The clinical diagnosis of LBDs can be challenging for physicians, particularly in the early stages of disease. Given the growing number of individuals affected by these neurodegenerative disorders, early and accurate diagnosis can lead to improved clinical management of patients. For this reason, information obtained from molecular imaging biomarkers is playing an increasingly important role in this framework. The present narrative review discusses both established milestones and new evidence on the use of molecular imaging tracers already part of the clinical practice as well as available evidence on new molecular imaging approaches in PD, PDD and DLB.

Neuroimaging is a mainstay in the evaluation of the effects of hypertension (HTN) on the brain. Nuclear magnetic resonance (MRI) is the most sensitive study for the evaluation and quantification of brain pathology, anatomy, and physiology, including the effects of hypertension. Computerized tomography (CT) remains an important modality of the rapid assessment of patients in the emergency setting, while positron emission tomography (PET) and single photon emission tomography (SPECT) provide information on metabolism and physiology in the evaluation of HTN on the brain, these are used more for research and less in the clinical setting due to cost, availability often only in academic centers and are limited by radiation exposure.

The aim of this review was to report the current literature concerning the use of nuclear imaging modalities for the investigation of the neurobiology of canine behavioral disorders. The conventionally used nuclear medicine modalities are positron emission tomography and single photon emission (computed) tomography. At this moment, information is scarce about their application in veterinary behavioral medicine and only present for single photon emission tomography studies in dogs, mainly using 99mTc-ethyl cysteinate dimer to assess brain perfusion (and indirectly neuronal function) and 123I-5-I-R91150 to evaluate the 5-hydroxytryptamine-2A receptor binding. Current results suggest that functional nuclear imaging provides useful noninvasive in vivo information about the neurobiology and therapeutic evaluation of canine behavioral disorders. Due to striking similarities with neurobiological alterations in human disorders, the dog also represents an interesting natural animal model for human neuropsychiatric diseases.

The institute of Nuclear Medicine (INM) Founded in 1961 with Professor J.E. Roberts as the first director (1961–1963), and later under the direction of Professor E S Williams (1963–1985) and matured into international Institute under the directorship of Professor Peter J. Ell. Leading the speciality in the UK, the INM developed with the Royal Postgraduate Medical School and the Institute of Cancer Research, the first intercollegiate Master of Science Course (MSc) in Nuclear Medicine. This gained wide recognition, and at the INM, some 100 MSc graduates, mostly from overseas, obtained their diploma over the ensuing years. This chapter will briefly summarise some significant early contributions from the institute of Nuclear Medicine.

In the UK, the institute of Nuclear Medicine in London has played an important role in the development of radionuclide investigation of brain. This chapter summarises the very early days of blood brain barrier imaging with labelled pertechnetate, and the use of 3" and 5" sodium iodide crystal scanners in the 60’s, with added simple data processing in the 70’s, progress was continuous, with the introduction of SPET, lyphophilic Tc99m labelled tracers for blood flow studies, the emergence of dopamine transporter imaging in patients with presumed Parkinson’s disease, followed by PET/CT and assessment of glucose metabolism with labelled FDG, and finally the UK introduction of PET/MR and the investigation of the dementias, with labelled amyloid.

Parkinson's disease is mainly considered as a motor disorder defined by a motor triad. However, various non-motor manifestations may be encountered in Parkinson's disease, including hyposmia, pain, fatigue, sleep disorders, cognitive and behavioral disorders. The pathophysiology of these signs is complex, not univocal and remains poorly understood. Functional imaging techniques either by positron emission tomography, single photon emission tomography or functional magnetic resonance imaging provide an invaluable opportunity to better understand the pathophysiology of these signs. In this paper, we present a review of the recent advances provided by functional imaging in this area.

Die Arbeit gibt einen Uberblick uber den Einsatz der SPECT-Bildgebung des prasynaptischen Dopamintransporters mit [ 123 I]FP-CIT bei der Abklarung von Parkinson-Syndromen. Abgehandelt wird der Stellenwert dieser Methodik beim Nachweis neurodegenerativer Parkinson-Syndrome, fur deren Fruh- und praklinische Diagnostik sowie fur die Beurteilung der Krankheitsprogression. In der Abgrenzung der symptomatischen PS und wichtiger Tremorsyndrome von den neurodegenerativen PS wird die Bedeutung normaler FP-CIT-SPECT-Befunde eingehend erlautert. Schlieslich wird der Stellenwert der Methode bei der Diagnostik der Lewy-Body-Demenz und deren Abgrenzung von der Alzheimer-Demenz beleuchtet. Kurze Betrachtungen zur okonomischen Seite von [ 123 I]FP-CIT-Untersuchungen runden die Ausfuhrungen ab.

Resume Une fille de dix ans a ete referee dans notre service pour scintigraphie osseuse en raison d’une hypercondylie unilaterale. Nous decrivons le role de la scintigraphie osseuse dans cette pathologie. L’hypercondylie est une pathologie rare de la croissance du cartilage condylien mandibulaire conduisant a une deformation faciale. La scintigraphie osseuse demontre le caractere actif ou inactif de l’hypercondylie et permet d’orienter la therapeutique. Une scintigraphie osseuse planaire, completee par une tomoscintigraphie couplee a la tomodensitometrie, a ete realisee chez notre patiente. Les vues planaires et tomoscintigraphiques ont montre une hyperfixation relative du condyle gauche. Cela a ete confirme par une quantification relative et a aide a la prise de decision d’un traitement chirurgical.

Objective: To know the effective doses (E) that can be given in the common multimodal procedures in nuclear medicine, Single Photon Emission Tomography and Positron Emission Tomography, combined with Computed Tomography, SPECT/CT and PET/CT. Effective dose will be expressed according to Background Equivalent Radiation Time (BERT) and the contribution of the CT scan to the total dose will also be studied. Material and methods: The effective dose of each procedure has been calculated as the sum of the external radiation dose (CT part) and internal one (radiopharmaceutical administration). Data from each side were collected through extensive literature search. Results: A range of minimum and maximum effective dose [Emin ,E max] associated with each procedure is shown. These doses range from 0.5 to 49.1 mSv. BERT ranges from 2.6 months to 20.4 years. The CT contribution to the total effective dose varies from 2.1% to 93%, according to the image acquisition protocol and its purpose. Performing a diagnostic CT scan increases the dose up to a factor of 4.3 times compared to the dose used for CT acquisition for attenuation correction and anatomic localization. Conclusions: This article focus on the effective dose level that can be given in multimodal procedures, bearing in mind that the data are subject to constant changes and should be updated periodically. It is important to know the dosimetric impact when the CT scan is added. The application of optimized protocols according to the indication of the study reduces the patient’s exposure without the loss of significant information.

Early and correct diagnosis of tumor recurrence and its differentiation from therapy-related changes is crucial for prompt and adequate management of glioma patients. The purpose of this study was to compare the efficacies of Tc-99m glucoheptonate (GHA) single photon emission tomography (SPECT) and F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in detection of recurrence in patients with glioma.A total of 90 patients with histopathologically proven glioma who had suspicion of recurrence clinically or on magnetic resonance imaging were evaluated using Tc-99m GHA SPECT and FDG PET/CT. Combination of clinical follow-up, repeat imaging, and biopsy (when available) was taken as gold standard.On the basis of gold standard, 59 patients were positive and 31 were negative for tumor recurrence. The sensitivity, specificity, and accuracy of GHA SPECT were 85%, 97%, and 89%, respectively, whereas those of FDG PET/CT were 70%, 97%, and 80%, respectively. On subgroup analysis, GHA SPECT performed better than FDG PET/CT in all grades except for grade II gliomas, where both were equally effective. In all, 15 patients had intermodality discordance, with GHA SPECT being correct in 13 of them.GHA SPECT appears to be a better imaging modality than FDG PET/CT for detection of recurrent gliomas.