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Seminars in Nuclear Medicine Nov 2023Renal scintigraphy is a centerpiece of nuclear medicine and is also commonly applied for (peri-)acute care. In this regard, referrals by the treating physician include:... (Review)
Review
Renal scintigraphy is a centerpiece of nuclear medicine and is also commonly applied for (peri-)acute care. In this regard, referrals by the treating physician include: I.) acute obstructions caused by gradual and infiltrative tumor growth or renal off-target effects under anti-tumor treatment, II.) functional issues in infants, for example, structural abnormalities such as duplex kidneys or uroliths in adults, which can also trigger III.) Infections of renal parenchyma. Renal radionuclide imaging is also requested due to IV.) acute trauma to the abdomen, for example, to assess renal scarring or upon further follow-up after reconstructive surgery. We will discuss clinical applications of (peri-)acute renal scintigraphy, along with future prospects on the use of more advanced nuclear imaging techniques such as renal positron emission tomography.
Topics: Humans; Emergencies; Kidney; Tomography, Emission-Computed, Single-Photon; Positron-Emission Tomography; Radionuclide Imaging
PubMed: 37236903
DOI: 10.1053/j.semnuclmed.2023.04.003 -
Endocrine Nov 2023The aim of this study is to review the clinical and laboratory characteristics, diagnostic and treatment modalities of tumor-induced osteomalacia (TIO) cases managed in...
PURPOSE
The aim of this study is to review the clinical and laboratory characteristics, diagnostic and treatment modalities of tumor-induced osteomalacia (TIO) cases managed in a single center.
MATERIAL METHODS
Demographic and clinical features, biochemical findings, diagnostic procedures, treatment modalities, and outcomes of nine patients who had the diagnosis of TIO were reviewed retrospectively.
RESULTS
Mean age of the study group (F/M: 4/5) was 45.8 ± 10.8 years, and mean time from the onset of symptoms to diagnosis was 4.7 ± 2.8 years. The clinical manifestations were muscle weakness and difficulty in walking (8/9), hip pain (3/9), multiple fractures (2/9), stress fracture (2/9). Mean plasma phosphorus concentration was 1.28 ± 0.4 mg/dl at presentation. We performed radionuclide imaging modalities (18F-FDG PET/CT, Ga68-DOTATATE PET/CT, octreotide scintigraphy) in seven of nine patients, and tumor was detected in all. Lower extremity (n = 6; %67), head region (n = 2; %22) and thorax (n = 1; %11) were the tumor locations of our cases. Eight patients underwent surgery and remission was achieved postoperatively in all of the operated patients and plasma phosphorus level normalized in 4 ± 2 days. Pathological examination revealed mesenchymal tumors with different subtypes. Recurrence occurred in three patients at 13 ± 10.5 months after the first surgery. Two patients were reoperated and radiotherapy was also performed in one of them.
CONCLUSION
Hypophosphatemia necessitates careful evaluation for the etiology. TIO is one of the important causes of adult-onset hypophosphatemic osteomalacia. Diagnosis of TIO is essential because the laboratory and clinical findings resolve after appropriate treatment.
Topics: Adult; Humans; Middle Aged; Neoplasms, Connective Tissue; Osteomalacia; Positron Emission Tomography Computed Tomography; Retrospective Studies; Paraneoplastic Syndromes; Hypophosphatemia; Phosphorus
PubMed: 37480497
DOI: 10.1007/s12020-023-03450-3 -
Seminars in Nuclear Medicine Nov 2023In this article the technique, interpretation, and diagnostic performance of scintigraphy for the diagnosis of acute pulmonary embolism (PE) are reviewed. Lung... (Review)
Review
In this article the technique, interpretation, and diagnostic performance of scintigraphy for the diagnosis of acute pulmonary embolism (PE) are reviewed. Lung scintigraphy has stood the test of time as a reliable and validated examination for the determination of PE. Ventilation/perfusion (V/Q) lung scintigraphy assesses the functional consequences of the clot on its downstream vascular bed in conjunction with the underlying ventilatory status of the affected lung region, in contrast to CT pulmonary angiography (CTPA), which visualizes presence of the clot within affected vessels. Most-commonly used ventilation radiopharmaceuticals are Technetium-99m labeled aerosols (such as Technetium-DTPA), or ultrafine particle suspensions (Tc-Technegas) which reach the distal lung in proportion to regional distribution of ventilation. Perfusion images are obtained after intravenous administration Tc-labeled macro-aggregated albumin particles which lodge in the distal pulmonary capillaries. Both planar and tomographic methods of imaging, each favored in different geographical regions, will be described. Guidelines for interpretation of scintigraphy have been issues by both the Society of Nuclear Medicine and Molecular Imaging, and by the European Association of Nuclear Medicine. Breast tissue is particularly radiosensitive during pregnancy due to its highly proliferative state and many guidelines recommend use of lung scintigraphy rather than CTPA in this population. Several maneuvers are available in order to further reduce radiation exposure including reducing radiopharmaceutical dosages or omitting ventilation altogether, functionally converting the study to a low-dose screening examination; if perfusion defects are present, further testing is necessary. Several groups have also performed perfusion-only studies during the COVID epidemic in order to reduce risk of respiratory contagion. In patients where perfusion defects are present, further testing is again necessary to avoid false-positive results. Improved availability of personal protective equipment, and reduced risk of serious infection, have rendered this maneuver moot in most practices. First introduced 60 years ago, subsequent advances in radiopharmaceutical development and imaging methods have positioned lung scintigraphy to continue to play an important clinical and research role in the diagnosis of acute PE.
Topics: Female; Pregnancy; Humans; Radiopharmaceuticals; Pulmonary Embolism; Lung; Radionuclide Imaging; Technetium Tc 99m Pentetate
PubMed: 37142520
DOI: 10.1053/j.semnuclmed.2023.04.002 -
Gut Nov 2023Symptoms in gastroparesis (Gp) and functional dyspepsia (FD) overlap; using egg protein substitute to measure gastric emptying of solids (GES), ~40% of patients are... (Clinical Trial)
Clinical Trial
OBJECTIVE
Symptoms in gastroparesis (Gp) and functional dyspepsia (FD) overlap; using egg protein substitute to measure gastric emptying of solids (GES), ~40% of patients are reclassified from Gp to FD, and vice versa. Our aim was to assess inter-individual and intra-individual coefficients of variation (COV) in GES in symptomatic patients with Gp or FD with documented slow or normal GES, respectively.
DESIGN
Scintigraphic GES (T and GE% at 2 and 4 hours) using a 320 kcal real egg meal (30% fat) was tested in the following: single measurements in 20 patients with diabetes mellitus (10 each type 1 and type 2); repeat GES to estimate COV measured: 3 days apart in 9 Gp, 4 weeks apart in 21 Gp and 18 with FD with normal GE assigned to placebo and in 70 patients at 94.3 weeks (median) apart.
RESULTS
COV for GE% at 4 hours and GE T were respectively 14.2% and 23.5% in FD and 27.5% and 33% in Gp; COV for GE% at 4 hours and GE T up to 4 weeks apart were 23.4% and 37.9% in FD and 20.1% and 33% in Gp. GE% at 2 hours showed less consistent results. However, >85% retained original diagnosis as normal or delayed. From clinical GES to baseline research for Gp group, repeat GES (after treatment) showed the COV for GE% at 4 hours was 37.3% at median 94.3 weeks, with 26/70 changed diagnoses.
CONCLUSION
The 320 kcal (30% fat) GES scintigraphic test provides consistent diagnosis in >85% and should be the standard test for suspected gastric emptying disorders.
Topics: Humans; Diabetes Mellitus; Dyspepsia; Gastric Emptying; Gastroparesis; Radionuclide Imaging
PubMed: 37726164
DOI: 10.1136/gutjnl-2023-330733 -
Journal of Integrative Neuroscience Dec 2023Computed tomography (CT) and magnetic resonance imaging (MRI) provide key structural information on brain pathophysiology. Positron emission tomography (PET) measures... (Review)
Review
Computed tomography (CT) and magnetic resonance imaging (MRI) provide key structural information on brain pathophysiology. Positron emission tomography (PET) measures metabolism in the living brain; it plays an important role in molecular neuroimaging and is rapidly expanding its field of application to the study of neurodegenerative diseases. Different PET radiopharmaceuticals allow characterization and quantization of biological processes at the molecular and cellular levels, from which many neurodegenerative diseases develop. In addition, hybrid imaging tools such as PET/CT and PET/MRI support the utility of PET, enabling the anatomical mapping of functional data. In this overview, we describe the most commonly used PET tracers in the diagnostic work-up of patients with Alzheimer's disease, Parkinson's disease, and other neurodegenerative diseases. We also briefly discuss the pathophysiological processes of tracer uptake in the brain, detailing their specific cellular pathways in clinical cases. This overview is limited to imaging agents already applied in human subjects, with particular emphasis on those tracers used in our department.
Topics: Humans; Positron Emission Tomography Computed Tomography; Nuclear Medicine; Positron-Emission Tomography; Neurodegenerative Diseases; Magnetic Resonance Imaging; Molecular Imaging
PubMed: 38176937
DOI: 10.31083/j.jin2206172 -
Experimental and Clinical... Apr 2024Brain death is defined as the complete and irreversible cessation of the entire brain function, including the brainstem. For the most part, the diagnosis is clinical,... (Review)
Review
Brain death is defined as the complete and irreversible cessation of the entire brain function, including the brainstem. For the most part, the diagnosis is clinical, and ancillary testing is only needed when clinical criteria are not satisfied. Differences exist in brain death diagnosis policy in the confirmation of brain death with ancillary testing and the particular test used. Demonstration of the absence of cerebral circulation is a reliable indicator of brain death. Currently, there are no agreed-on universal criteria for ancillary imaging investigation. However, several guidelines and meta-analyses have referred to radionuclide imaging as the most reliable, accurate, and validated ancillary imaging procedure in the confirmation of brain death. Whenever available, lipophilic agents should be preferred using tomographic imaging in all or as needed. False results may occur because of slight temporal delays in flow-function interaction, and such findings may carry prognostic information. Detectable cerebral circulation in the clinical presence of brain death most probably indicates that the process of dying is not yet complete. The results of radionuclide studies may also suggest that the loss of viability in a significant proportion of brain tissue is not compatible with life.
Topics: Brain Death; Humans; Predictive Value of Tests; Cerebrovascular Circulation; Brain; Radiopharmaceuticals; Reproducibility of Results; Perfusion Imaging; Prognosis
PubMed: 38775696
DOI: 10.6002/ect.BDCDSymp.L15 -
Analytical Chemistry Aug 2023Scanning ion conductance microscopy (SICM) is a promising tool for visualizing the dynamics of nanoscale cell surface topography. However, there are still no guidelines...
Scanning ion conductance microscopy (SICM) is a promising tool for visualizing the dynamics of nanoscale cell surface topography. However, there are still no guidelines for fabricating nanopipettes with ideal shape consisting of small apertures and thin glass walls. Therefore, most of the SICM imaging has been at a standstill at the submicron scale. In this study, we established a simple and highly reproducible method for the fabrication of nanopipettes with sub-20 nm apertures. To validate the improvement in the spatial resolution, we performed time-lapse imaging of the formation and disappearance of endocytic pits as a model of nanoscale time-lapse topographic imaging. We have also successfully imaged the localization of the hot spot and the released extracellular vesicles. The nanopipette fabrication guidelines for the SICM nanoscale topographic imaging can be an essential tool for understanding cell-cell communication.
Topics: Microscopy; Radionuclide Imaging; Cell Communication; Cell Membrane; Extracellular Vesicles; Ions
PubMed: 37599426
DOI: 10.1021/acs.analchem.3c01010 -
The Never-ending Story: Assessing coronary collateral circulation with myocardial perfusion imaging.Journal of Nuclear Cardiology :... Dec 2023The role of coronary collateral circulation has been thoroughly studied, and myocardial perfusion imaging has been a frequently employed method. Even angiographic...
The role of coronary collateral circulation has been thoroughly studied, and myocardial perfusion imaging has been a frequently employed method. Even angiographic invisible collaterals can support some degree of tracer uptake, but the clinical role of this evaluation is still uncertain, and this remains the main issue that should be clarified.
Topics: Humans; Myocardial Perfusion Imaging; Collateral Circulation; Coronary Angiography; Heart; Coronary Circulation; Tomography, Emission-Computed, Single-Photon; Coronary Artery Disease
PubMed: 37291456
DOI: 10.1007/s12350-023-03294-4 -
Journal of Nuclear Cardiology :... Dec 2023Bone scintigraphy imaging is frequently used to investigate patients with suspected transthyretin cardiac amyloidosis (ATTR-CM). However, the reported accuracy for... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Bone scintigraphy imaging is frequently used to investigate patients with suspected transthyretin cardiac amyloidosis (ATTR-CM). However, the reported accuracy for interpretation approaches has changed over time. We performed a systematic review and meta-analysis to determine the diagnostic accuracy of visual planar grading, heart-to-contralateral (HCL) ratio, and quantitative analysis of SPECT imaging and evaluate reasons for shifts in reported accuracy.
METHODS
We performed a systematic review to identify studies of the diagnostic accuracy of bone scintigraphy for ATTR-CM from 1990 until February 2023 using PUBMED and EMBASE. Studies were reviewed separately by two authors for inclusion and for risk of bias assessment. Summary receiver operating characteristic curves and operating points were determined with hierarchical modeling.
RESULTS
Out of a total of 428 identified studies, 119 were reviewed in detail and 23 were included in the final analysis. The studies included a total of 3954 patients, with ATTR-CM diagnosed in 1337 (39.6%) patients and prevalence ranging from 21 to 73%. Visual planar grading and quantitative analysis had higher diagnostic accuracy (.99) than HCL ratio (.96). Quantitative analysis of SPECT imaging had the highest specificity (97%) followed by planar visual grade (96%) and HCL ratio (93%). ATTR-CM prevalence accounted for some of the observed between study heterogeneity.
CONCLUSIONS
Bone scintigraphy imaging is highly accurate for identifying patients with ATTR-CM, with between study heterogeneity in part explained by differences in disease prevalence. We identified small differences in specificity, which may have important clinical implications when applied to low-risk screening populations.
Topics: Humans; Prealbumin; Amyloid Neuropathies, Familial; Tomography, X-Ray Computed; Radionuclide Imaging; Cardiomyopathies
PubMed: 37226006
DOI: 10.1007/s12350-023-03297-1 -
Radiology Aug 2023
Topics: Humans; Fluorodeoxyglucose F18; Positron Emission Tomography Computed Tomography; Lung Neoplasms; Positron-Emission Tomography; Gallium Radioisotopes; Quinolines
PubMed: 37552076
DOI: 10.1148/radiol.231768