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1.
Mod Pathol ; : 100514, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38763423

RESUMO

The EWSR1::PBX3 fusion gene, commonly associated with cutaneous syncytial myoepitheliomas, is also found in myoepithelial tumors (METs) of bone and soft tissue. These tumors typically demonstrate benign histology and favorable outcomes. This study examines six previously unreported intraosseous METs harboring the EWSR1::PBX3 fusion, focusing on their histopathologic characteristics, immunophenotype, clinical and radiographic profiles, and patient outcomes. The cohort comprised five males and one female, aged 25 to 65 years (median age 31), with tumors located in the proximal tibia (three cases), distal radius (two cases), and ilium (one case), and sizes between 3.2 to 12.2 cm (median size 3.9 cm). Imaging showed osteolytic lesions with varying degrees of cortical involvement and soft tissue extension in three cases. Histologically, four tumors showed mainly uniform oval-to-spindled cells in syncytial or fascicular arrangements within a collagenous matrix, displaying either bland nuclear features or mild atypia, and low to slightly elevated mitotic activity (≤1 per 10 HPF in three cases and 6 per 10 HPFs in one), classifying them as benign or atypical METs. In contrast, two tumors exhibited pronounced nuclear atypia with ovoid, spindled, epithelioid and round cells, hyperchromatic nuclei, inconspicuous nucleoli, increased N/C ratios, high mitotic rates (17 and 19 per 10 HPFs), and extensive necrosis. Both tumors behaved aggressively-one patient underwent amputation after neoadjuvant chemotherapy and radiation, while the other died with the disease. Immunohistochemically, the tumors consistently expressed EMA and S100, but lacked keratin (AE1/AE3) expression. Our study demonstrates that bone METs with EWSR1::PBX3 fusions encompass a histologic continuum from benign to malignant, with benign/atypical METs mirroring their cutaneous analogs in morphology and malignant variants distinguished by heterogenous cytologic and architectural features, pronounced nuclear atypia, and high mitotic rates.

3.
Opt Lett ; 49(8): 2193-2196, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621109

RESUMO

Photonic-assisted signal processing of high-bandwidth signals emerges as a solution for challenges encountered in electronic-based processing. Here we present a concept for a compact, photonic-assisted digital-to-analog converter (DAC) and optical IQ-modulator in one single integrated device based on two innovative concepts: a segmented Mach-Zehnder modulator and orthogonal sampling. For electrically driving the modulator, only a single radio frequency oscillator and no pulse source or electrical DAC are required. The presented and simulated proof-of-concept device with six segments can generate a multi-level and high-bandwidth signal from low-bandwidth electronic drivers; e.g., we show the generation of a 120 Gbps data rate, 16-quadrature amplitude modulation (16-QAM, 30 Gbaud) signal solely based on low-bandwidth (5 GHz) non-return-to-zero (NRZ) signals. Integrated on a silicon photonic platform, the device provides fixable speed and bandwidth operations, positioning it as a viable solution for diverse communication systems.

4.
Sci Rep ; 14(1): 7631, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561374

RESUMO

The drag loss behavior of a disengaged wet clutch is influenced, among other things, by the movement of the plates. Therefore, knowledge about the plate movement is essential for investigating and optimizing the drag loss behavior. This paper presents a methodology for image-based measurement of plate movement in disengaged wet clutches. A drag torque test rig is equipped with a camera to create the image series. The oil displacement from the measuring zone is crucial to obtain permanent optical access to the clutch pack. The rough plate positions are determined by segmentation using thresholding and template matching. Using the Canny edge detector significantly improves the accuracy of the position evaluation. The plate positions are finally converted into a metric unit based on the real plate thicknesses. The clearances are calculated from the determined positions of two adjacent plates. In the ideal case, an evaluation accuracy in the range of a few micrometers can be achieved. The image evaluation methodology is universally applicable to different clutch sizes, friction systems, plate types, and plate numbers. The methodology enables researchers to generate fundamental knowledge and derive design guidelines based on this, for example. In the development phase, it can also be used to optimize the design and operating parameters.

5.
Sci Rep ; 14(1): 9241, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649463

RESUMO

Fundamental knowledge of wet clutches' drag loss behavior is essential for designing low-loss clutch systems. In contrast to the widely investigated injection lubrication, more comprehensive knowledge is needed on the drag loss behavior of dip-lubricated wet clutches. In the development phase, data-driven models allow drag loss predictions with low computational effort and, at the same time, sufficient accuracy. Therefore, this study aimed to deepen and expand knowledge of the drag loss behavior of dip-lubricated wet clutches based on experimental investigations. Moreover, the investigations were designed and conducted so that the generated data and findings can be used in further research for building data-driven prediction models. The investigations were conducted on two clutch systems from automotive and industrial applications. The practice-relevant parameters of clearance, oil level, oil viscosity, and plate shape were investigated based on a mixed-level full factorial design. The evaluation shows that a reduction in drag loss can be achieved primarily by increasing the clearance, reducing the oil viscosity, and choosing waved plates. The obtained drag loss behavior can be traced back to the form of oil displacement from the gaps. The displacement process, in turn, is influenced by the operating and geometry parameters. Although the flow in the gaps develops differently for dip and injection lubrication over differential speed, the study shows comparable integral effects of the influencing parameters for both types of lubrication. The generated datasets contain the investigated parameters as features and characteristic drag loss values as targets. The findings can support the selection and configuration of the machine learning algorithm and the validation of the trained models. The described procedure can serve as a template for generating and analyzing datasets for data-driven modeling of wet clutches' drag losses.

6.
Int J Infect Dis ; 142: 106997, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38458424

RESUMO

A patient with disseminated nocardiosis developed pancytopenia after treatment with recombinant interferon-gamma (IFN-γ). While no previous clinical reports link pancytopenia to IFN-γ, our observations align with basic research on myelosuppressive effects of IFN-γ. Adjunctive IFN-γ may improve standard nocardiosis therapy, but vigilant monitoring of its hematologic effects is necessary.


Assuntos
Nocardiose , Pancitopenia , Humanos , Interferon gama , Pancitopenia/etiologia , Nocardiose/diagnóstico , Nocardiose/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico
7.
Sci Rep ; 14(1): 4286, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383592

RESUMO

Cigarette smoking is a major preventable cause of morbidity and mortality. While quitting smoking is the best option, switching from cigarettes to non-combustible alternatives (NCAs) such as e-vapor products is a viable harm reduction approach for smokers who would otherwise continue to smoke. A key challenge for the clinical assessment of NCAs is that self-reported product use can be unreliable, compromising the proper evaluation of their risk reduction potential. In this cross-sectional study of 205 healthy volunteers, we combined comprehensive exposure characterization with in-depth multi-omics profiling to compare effects across four study groups: cigarette smokers (CS), e-vapor users (EV), former smokers (FS), and never smokers (NS). Multi-omics analyses included metabolomics, transcriptomics, DNA methylomics, proteomics, and lipidomics. Comparison of the molecular effects between CS and NS recapitulated several previous observations, such as increased inflammatory markers in CS. Generally, FS and EV demonstrated intermediate molecular effects between the NS and CS groups. Stratification of the FS and EV by combustion exposure markers suggested that this position on the spectrum between CS and NS was partially driven by non-compliance/dual use. Overall, this study highlights the importance of in-depth exposure characterization before biological effect characterization for any NCA assessment study.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Expossoma , Abandono do Hábito de Fumar , Produtos do Tabaco , Vaping , Humanos , Estudos Transversais , Multiômica
8.
Nat Commun ; 15(1): 1709, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402242

RESUMO

With the advent of serial X-ray crystallography on microfocus beamlines at free-electron laser and synchrotron facilities, the demand for protein microcrystals has significantly risen in recent years. However, by in vitro crystallization extensive efforts are usually required to purify proteins and produce sufficiently homogeneous microcrystals. Here, we present InCellCryst, an advanced pipeline for producing homogeneous microcrystals directly within living insect cells. Our baculovirus-based cloning system enables the production of crystals from completely native proteins as well as the screening of different cellular compartments to maximize chances for protein crystallization. By optimizing cloning procedures, recombinant virus production, crystallization and crystal detection, X-ray diffraction data can be collected 24 days after the start of target gene cloning. Furthermore, improved strategies for serial synchrotron diffraction data collection directly from crystals within living cells abolish the need to purify the recombinant protein or the associated microcrystals.


Assuntos
Lasers , Síncrotrons , Cristalografia por Raios X , Cristalização , Proteínas Recombinantes/genética
9.
J Synchrotron Radiat ; 31(Pt 1): 186-194, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37971957

RESUMO

Here, high-throughput tomography (HiTT), a fast and versatile phase-contrast imaging platform for life-science samples on the EMBL beamline P14 at DESY in Hamburg, Germany, is presented. A high-photon-flux undulator beamline is used to perform tomographic phase-contrast acquisition in about two minutes which is linked to an automated data processing pipeline that delivers a 3D reconstructed data set less than a minute and a half after the completion of the X-ray scan. Combining this workflow with a sophisticated robotic sample changer enables the streamlined collection and reconstruction of X-ray imaging data from potentially hundreds of samples during a beam-time shift. HiTT permits optimal data collection for many different samples and makes possible the imaging of large sample cohorts thus allowing population studies to be attempted. The successful application of HiTT on various soft tissue samples in both liquid (hydrated and also dehydrated) and paraffin-embedded preparations is demonstrated. Furthermore, the feasibility of HiTT to be used as a targeting tool for volume electron microscopy, as well as using HiTT to study plant morphology, is demonstrated. It is also shown how the high-throughput nature of the work has allowed large numbers of `identical' samples to be imaged to enable statistically relevant sample volumes to be studied.


Assuntos
Robótica , Síncrotrons , Raios X , Tomografia Computadorizada por Raios X , Alemanha
11.
Sci Rep ; 13(1): 17193, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37821467

RESUMO

Fundamental knowledge of the oil flow in a disengaged wet clutch is essential for optimizing the cooling performance and the drag losses. However, no fundamental information on the oil flow and drag torque generation is available for dip-lubricated wet clutches. Therefore, the oil flow and drag torque generation in the sub-millimeter gap of a dip-lubricated wet clutch was experimentally investigated for three practically relevant oil levels. To enable optical access to the gap, transparent components were used. Further, a high-speed camera was used to capture the oil flow in the gap and grooving. Independent of the set oil level, the gap is oil-filled at low differential speeds, resulting in a single-phase flow. The drag torque increases approximately linearly with increasing differential speed due to the fluid shearing. In certain regions of the waffle grooving, air bubbles form locally. The air bubbles preferably occur in the grooves oriented in the radial direction, while the grooves oriented in the peripheral direction are filled with oil. Above a certain differential speed, the oil is continuously displaced from the gap, starting from the inside, due to the increasing centrifugal force. Consequently, the drag torque increases in a degressive manner until a maximum value is finally reached. The ongoing displacement of oil from the gap eventually results in a decrease in the drag torque. A steady drag torque is generated only when the oil is almost entirely displaced from the gap. Since the oil displacement from the gap already commences at a low differential speed, the cooling performance is limited for dip-lubricated wet clutches. The continuous displacement of oil from the gap can be held up, among other things, by increasing the oil level.

12.
Tomography ; 9(5): 1577-1591, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37736979

RESUMO

This study evaluates how far T2 mapping can identify arthroscopically confirmed pathologies in the long biceps tendon (LBT) and quantify the T2 values in healthy and pathological tendon substance. This study comprised eighteen patients experiencing serious shoulder discomfort, all of whom underwent magnetic resonance imaging, including T2 mapping sequences, followed by shoulder joint arthroscopy. Regions of interest were meticulously positioned on their respective T2 maps, capturing the sulcal portion of the LBT and allowing for the quantification of the average T2 values. Subsequent analyses included the calculation of diagnostic cut-off values, sensitivities, and specificities for the detection of tendon pathologies, and the calculation of inter-reader correlation coefficients (ICCs) involving two independent radiologists. The average T2 value for healthy subjects was measured at 23.3 ± 4.6 ms, while patients with tendinopathy displayed a markedly higher value, at 47.9 ± 7.8 ms. Of note, the maximum T2 value identified in healthy tendons (29.6 ms) proved to be lower than the minimal value measured in pathological tendons (33.8 ms), resulting in a sensitivity and specificity of 100% (95% confidence interval 63.1-100) across all cut-off values ranging from 29.6 to 33.8 ms. The ICCs were found to range from 0.93 to 0.99. In conclusion, T2 mapping is able to assess and quantify healthy LBTs and can distinguish them from tendon pathology. T2 mapping may provide information on the (ultra-)structural integrity of tendinous tissue, facilitating early diagnosis, prompt therapeutic intervention, and quantitative monitoring after conservative or surgical treatments of LBT.


Assuntos
Tendões , Humanos , Tendões/diagnóstico por imagem , Braço
13.
Opt Express ; 31(19): 30160-30170, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710564

RESUMO

A group-delay-unit-based integrated silicon photonic integrated circuit (PIC) is employed as a reconfigurable analog radio frequency decoder, which provides a real-time temporal and spectral analysis of any arbitrary multi-tone signal in the micro- and mm-wave range. The circuit is based on cascaded Mach-Zehnder interferometer embedded silicon microring resonators as variable delay units. The temporal decoding of the multi-tone input signal is demonstrated by tuning the signal with respect to the ring resonator delay and resonance. A one-to-one conformal time-to-frequency mapping provides real-time spectral decoding of the signal under test without additional digital signal processing. The idea is validated by several experimental results with single-tone and two-tone input signals in a compact, low-power, silicon PIC. The proposed real-time temporal analog frequency decoder may be very intriguing for high-speed, low-latency wireless applications, such as autonomous driving and 6G.

14.
In Vivo ; 37(5): 1951-1959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37652498

RESUMO

BACKGROUND/AIM: To determine the interaction of gemcitabine in chemoradiotherapy with heavy carbon ions in vitro in a mucoepidermoid carcinoma (MEC) cell line. MATERIALS AND METHODS: The human lymphatic MEC metastasis cell line NCI-H292 was used. The cells were treated with photons, carbon ions, and gemcitabine. Survival fractions (SF), apoptosis, and cell cycle progression were analyzed. A paired two-sided t-test was used. Significance was defined as p<0.05. RESULTS: Cell proliferation assays showed a significant reduction in SF for combined photon chemoradiation versus photons only. The linear-quadratic fits of combined therapy with carbon ion dose of 0 to 2.5 Gy led to reductions of mean 15% in SF. The LD50 (lethal radiation dose required to reduce cell survival by 50%) for carbon ions only was 0.7 Gy and for carbon ions with gemcitabine 0.6 Gy. The LD50 for photons (with gemcitabine) was 2.8 Gy (2.0 Gy) and for carbon ions (with gemcitabine) 0.7 Gy (0.6 Gy), resulting in a relative biological effectiveness at 10% cell survival (RBE10) of 3.0 (2.7). Carbon ions and photons reduced S phase and increased G2/M phase cell distribution. Isolated treatment with gemcitabine as well as combination with photons led to prolonged S phase transit, whereas combined treatment with carbon ions led to early accumulation in G2/M phase. A significant increase in the sub-G1 population as a hint of relevant number of apoptotic cells was not observed. CONCLUSION: Gemcitabine showed radiosensitizing effects in combination with photons. The combination of gemcitabine and carbon ions had independent additive effects. Carbon ions only had a RBE10 of 3.0, compared to photons only. The combination of gemcitabine, photon, and carbon ions in patients with MEC seems promising and warrants further investigation.


Assuntos
Carcinoma Mucoepidermoide , Radioterapia com Íons Pesados , Humanos , Gencitabina , Desoxicitidina/farmacologia , Carcinoma Mucoepidermoide/tratamento farmacológico , Linhagem Celular Tumoral , Radioterapia com Íons Pesados/métodos , Quimiorradioterapia/métodos , Fótons/uso terapêutico , Carbono/uso terapêutico , Íons
15.
Cells ; 12(14)2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37508551

RESUMO

Based on indirect evidence, increased mucosal translocation of gut-derived microbial macromolecules has been proposed as an important pathomechanism in HIV infection. Here, we quantified macromolecule translocation across intestinal mucosa from treatment-naive HIV-infected patients, HIV-infected patients treated by combination antiretroviral therapy, and HIV-negative controls and analyzed the translocation pathways involved. Macromolecule permeability was quantified by FITC-Dextran 4000 (FD4) and horseradish peroxidase (HRP) flux measurements. Translocation pathways were addressed using cold inhibition experiments. Tight junction proteins were characterized by immunoblotting. Epithelial apoptosis was quantified and translocation pathways were further characterized by flux studies in T84 cell monolayers using inducers and inhibitors of apoptosis and endocytosis. In duodenal mucosa of untreated but not treated HIV-infected patients, FD4 and HRP permeabilities were more than a 4-fold increase compared to the HIV-negative controls. Duodenal macromolecule permeability was partially temperature-dependent and associated with epithelial apoptosis without altered expression of the analyzed tight junction proteins. In T84 monolayers, apoptosis induction increased, and both apoptosis and endocytosis inhibitors reduced macromolecule permeability. Using quantitative analysis, we demonstrate the increased macromolecule permeability of the intestinal mucosa in untreated HIV-infected patients. Combining structural and mechanistic studies, we identified two pathways of increased macromolecule translocation in HIV infection: transcytosis and passage through apoptotic leaks.


Assuntos
Infecções por HIV , Humanos , Infecções por HIV/metabolismo , Mucosa Intestinal/metabolismo , Proteínas de Junções Íntimas/metabolismo , Duodeno/metabolismo , Transcitose
16.
Clin Immunol ; 254: 109712, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37506745

RESUMO

Little is known about the CD8+ T cell functionality in the coronavirus disease 2019 (COVID-19). Therefore, we examined twenty-five hospitalized COVID-19 patients with moderate (MD) or severe disease (SD) as well as seventeen SARS-CoV-2-unexposed persons regarding the cytolytic and cytokine-producing reactivity of their CD8+ T cells. Reactive CD8+ T cells were detectable in 90% of the unexposed persons, confirming high cross-reactive immune memory in the general population. Compared to unexposed persons and MD patients, SD patients had higher numbers of SARS-CoV-2 reactive CD8+ T cells with cytolytic function that can simultaneously produce inflammatory cytokines. In addition, SD patients showed higher CD8+ T cell reactivity against non-SARS-CoV-2-related viruses, which was mainly mediated by cytolytic response. Sequence alignments showed that cross-reactivities with the Spike protein could contribute to the expansion of such cells. Since insufficiently regulated cytolytic CD8+ T cells can damage peripheral and vascular tissue structures, high levels of both SARS-CoV-2-reactive and heterologously activated cytolytic CD8+ T cells could favor severe disease progression.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Linfócitos T CD8-Positivos , Linfócitos T CD4-Positivos , Linfócitos T Citotóxicos
17.
Nat Struct Mol Biol ; 30(7): 970-979, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37386213

RESUMO

Proton transport is indispensable for cell life. It is believed that molecular mechanisms of proton movement through different types of proton-conducting molecules have general universal features. However, elucidation of such mechanisms is a challenge. It requires true-atomic-resolution structures of all key proton-conducting states. Here we present a comprehensive function-structure study of a light-driven bacterial inward proton pump, xenorhodopsin, from Bacillus coahuilensis in all major proton-conducting states. The structures reveal that proton translocation is based on proton wires regulated by internal gates. The wires serve as both selectivity filters and translocation pathways for protons. The cumulative results suggest a general concept of proton translocation. We demonstrate the use of serial time-resolved crystallography at a synchrotron source with sub-millisecond resolution for rhodopsin studies, opening the door for principally new applications. The results might also be of interest for optogenetics since xenorhodopsins are the only alternative tools to fire neurons.


Assuntos
Bombas de Próton , Prótons , Bombas de Próton/química , Transporte de Íons
18.
Oncol Res Treat ; 46(7-8): 296-302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37311423

RESUMO

INTRODUCTION: The hepatitis E virus (HEV) represents an important cause of viral hepatitis and could cause chronic infections in immunocompromised patients. However, data about immunocompromised patients other than solid organ transplant recipients are limited. METHODS: We identified patients from a laboratory database and retrospectively compiled and analyzed clinical as well as laboratory data in detail. RESULTS: Overall, 22 severely immunosuppressed patients, excluding solid organ transplant recipients, were identified. Four patients did not experience viral clearance (one without and three despite ribavirin therapy). Three patients acquired the infection after allogeneic hematopoietic stem cell transplantation (alloHSCT) and recovered spontaneously, whereas another patient, infected prior to alloHSCT, developed a chronic infection. Four patients failed to clear HEV, resulting in fatal liver failure in 2 patients. The CD4+ cell counts increased in all but 1 patient attaining a sustained virological response (SVR), as compared to patients with clinical failure. Severe immunoglobulin deficiency did not appear to obviate the control of HEV. Six of ten (60%) patients with and nine of 12 (75%) patients without ribavirin therapy achieved an SVR. CONCLUSIONS: Upfront ribavirin therapy does not appear mandatory in patients without CD4+ lymphopenia, but a prolonged HEV replication carries the risk of liver failure. Our data suggest that chronic HEV infections could cause T-cell exhaustion, which might be overruled with ribavirin therapy.


Assuntos
Vírus da Hepatite E , Hepatite E , Falência Hepática , Humanos , Hepatite E/tratamento farmacológico , Hepatite E/induzido quimicamente , Ribavirina/uso terapêutico , Antivirais/uso terapêutico , Estudos Retrospectivos , Vírus da Hepatite E/fisiologia , Falência Hepática/induzido quimicamente , Falência Hepática/tratamento farmacológico
19.
J Clin Med ; 12(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37176550

RESUMO

This study investigated the ability of T2 mapping to assess the glenoid labrum and to differentiate between healthy labral substances and superior labral anterior posterior (SLAP) lesions using arthroscopy as the gold standard. Eighteen patients (mean age: 52.4 ± 14.72 years, 12 men) with shoulder pain were examined using 3-Tesla T2 mapping. All the patients underwent shoulder arthroscopy. Using morphological sequences for correlation, regions of interest covering the entire labral substance were placed in the corresponding T2 maps. The diagnostic cutoff values, sensitivities, and specificities, as well as the inter-reader correlation coefficients (ICCs) determined by two independent radiologists, were calculated. The mean T2 value was 20.8 ± 2.4 ms for the healthy labral substances and 37.7 ± 10.63 ms in the patients with SLAP lesions. The maximum T2 value in normal labrum (21.2 ms) was lower than the minimum T2 value in the patients with SLAP lesions (27.8 ms), leading to sensitivities, specificities, and positive and negative predictive values of 100% (95% CI 54.1-100.0) for all the cutoff values between 21.2 and 27.8 ms. The ICCs ranged from 0.91 to 0.99. In summary, the data suggest that evaluation and quantification of the labral (ultra)structural integrity using T2 mapping may allow discrimination between arthroscopically confirmed SLAP lesions and a healthy glenoid labrum. T2 mapping may therefore be helpful in diagnosing patients with suspected labral damage.

20.
Orthopadie (Heidelb) ; 52(6): 495-503, 2023 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-37106098

RESUMO

BACKGROUND AND AIM: In contrast to standard methods (sonography, X­ray, CT (computed tomography), MRI (magnetic resonance imaging), numerous diseases of the foot or ankle can be diagnosed using SPECT/CT (single photon emission computed tomography/computed tomography) with regard to their clinical relevance with high accuracy (up to > 90%). The aim of this review is to provide an up-to-date overview of the importance of SPECT/CT in selected diseases of the foot and ankle. MATERIAL AND METHODS: A literature search was carried out in the Pubmed database using the following terms: SPECT/CT, SPECT, skeletal scintigraphy, CT, computed tomography, foot and ankle disease, OSG, tarsal root, foot pain. The publications were selected with regard to questions and diagnoses that frequently occur in foot and ankle diagnostics. Furthermore, papers that describe a more precise diagnosis, a change in therapy management or a reduction in symptoms due to the use of SPECT/CT were selected. RESULTS: Several studies have shown that a focally increased bone metabolism in osteoarthritis and osteochondral lesions correlates significantly with the development of pain. The presence of symptomatic ossicles such as the os naviculare accessorium type II and os trigonum can be clearly demonstrated with the help of SPECT/CT and cannot be assigned as the source of the symptoms as accurately with any other imaging method. Bony reactions in the area of coalitions, arthrodesis, osteosynthesis, occult fractures, prostheses and diabetic foot cannot be detected with comparable accuracy using any other imaging method, so that therapy concepts in unclear cases, based only on standard imaging are changed in up to 2/3 of cases by SPECT/CT information. DISCUSSION AND CONCLUSION: SPECT/CT is useful when there are clinical uncertainties despite standard imaging.


Assuntos
Medicina Nuclear , Tálus , Humanos , Tornozelo/patologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X , Tálus/patologia , Dor/patologia
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