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1.
CA Cancer J Clin ; 72(1): 34-56, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34792808

RESUMEN

Radiation therapy (RT) continues to play an important role in the treatment of cancer. Adaptive RT (ART) is a novel method through which RT treatments are evolving. With the ART approach, computed tomography or magnetic resonance (MR) images are obtained as part of the treatment delivery process. This enables the adaptation of the irradiated volume to account for changes in organ and/or tumor position, movement, size, or shape that may occur over the course of treatment. The advantages and challenges of ART maybe somewhat abstract to oncologists and clinicians outside of the specialty of radiation oncology. ART is positioned to affect many different types of cancer. There is a wide spectrum of hypothesized benefits, from small toxicity improvements to meaningful gains in overall survival. The use and application of this novel technology should be understood by the oncologic community at large, such that it can be appropriately contextualized within the landscape of cancer therapies. Likewise, the need to test these advances is pressing. MR-guided ART (MRgART) is an emerging, extended modality of ART that expands upon and further advances the capabilities of ART. MRgART presents unique opportunities to iteratively improve adaptive image guidance. However, although the MRgART adaptive process advances ART to previously unattained levels, it can be more expensive, time-consuming, and complex. In this review, the authors present an overview for clinicians describing the process of ART and specifically MRgART.


Asunto(s)
Imagen por Resonancia Magnética Intervencional/métodos , Neoplasias/radioterapia , Aceleradores de Partículas , Oncología por Radiación/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Imagen por Resonancia Magnética Intervencional/historia , Imagen por Resonancia Magnética Intervencional/instrumentación , Imagen por Resonancia Magnética Intervencional/tendencias , Neoplasias/diagnóstico por imagen , Oncología por Radiación/historia , Oncología por Radiación/instrumentación , Oncología por Radiación/tendencias , Planificación de la Radioterapia Asistida por Computador/historia , Planificación de la Radioterapia Asistida por Computador/instrumentación , Planificación de la Radioterapia Asistida por Computador/tendencias
2.
Nature ; 615(7954): 813-816, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36991189

RESUMEN

The proton is one of the main building blocks of all visible matter in the Universe1. Among its intrinsic properties are its electric charge, mass and spin2. These properties emerge from the complex dynamics of its fundamental constituents-quarks and gluons-described by the theory of quantum chromodynamics3-5. The electric charge and spin of protons, which are shared among the quarks, have been investigated previously using electron scattering2. An example is the highly precise measurement of the electric charge radius of the proton6. By contrast, little is known about the inner mass density of the proton, which is dominated by the energy carried by gluons. Gluons are hard to access using electron scattering because they do not carry an electromagnetic charge. Here we investigated the gravitational density of gluons using a small colour dipole, through the threshold photoproduction of the J/ψ particle. We determined the gluonic gravitational form factors of the proton7,8 from our measurement. We used a variety of models9-11 and determined, in all cases, a mass radius that is notably smaller than the electric charge radius. In some, but not all cases, depending on the model, the determined radius agrees well with first-principle predictions from lattice quantum chromodynamics12. This work paves the way for a deeper understanding of the salient role of gluons in providing gravitational mass to visible matter.

3.
Nature ; 611(7935): 265-270, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36261531

RESUMEN

The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities1 that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities2 map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades2. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.

4.
Nature ; 609(7928): 685-688, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36131036

RESUMEN

Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin of cosmological FRBs is still not settled. Here we report the detection of 1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref. 9). These observations show irregular short-time variation of the Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (AU; Earth-Sun distance) of the source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.

5.
Nature ; 589(7840): 52-58, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408373

RESUMEN

With the proliferation of ultrahigh-speed mobile networks and internet-connected devices, along with the rise of artificial intelligence (AI)1, the world is generating exponentially increasing amounts of data that need to be processed in a fast and efficient way. Highly parallelized, fast and scalable hardware is therefore becoming progressively more important2. Here we demonstrate a computationally specific integrated photonic hardware accelerator (tensor core) that is capable of operating at speeds of trillions of multiply-accumulate operations per second (1012 MAC operations per second or tera-MACs per second). The tensor core can be considered as the optical analogue of an application-specific integrated circuit (ASIC). It achieves parallelized photonic in-memory computing using phase-change-material memory arrays and photonic chip-based optical frequency combs (soliton microcombs3). The computation is reduced to measuring the optical transmission of reconfigurable and non-resonant passive components and can operate at a bandwidth exceeding 14 gigahertz, limited only by the speed of the modulators and photodetectors. Given recent advances in hybrid integration of soliton microcombs at microwave line rates3-5, ultralow-loss silicon nitride waveguides6,7, and high-speed on-chip detectors and modulators, our approach provides a path towards full complementary metal-oxide-semiconductor (CMOS) wafer-scale integration of the photonic tensor core. Although we focus on convolutional processing, more generally our results indicate the potential of integrated photonics for parallel, fast, and efficient computational hardware in data-heavy AI applications such as autonomous driving, live video processing, and next-generation cloud computing services.

6.
Ann Oncol ; 35(2): 200-210, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37956738

RESUMEN

BACKGROUND: Fibroblast growth factor receptor 3 (FGFR3) alterations are oncogenic drivers of urothelial carcinoma (UC). Pemigatinib is a selective, oral inhibitor of FGFR1-3 with antitumor activity. We report the efficacy and safety of pemigatinib in the open-label, single-arm, phase II study of previously treated, unresectable or metastatic UC with FGFR3 alterations (FIGHT-201; NCT02872714). PATIENTS AND METHODS: Patients ≥18 years old with FGFR3 mutations or fusions/rearrangements (cohort A) and other FGF/FGFR alterations (cohort B) were included. Patients received pemigatinib 13.5 mg once daily continuously (CD) or intermittently (ID) until disease progression or unacceptable toxicity. The primary endpoint was centrally confirmed objective response rate (ORR) as per RECIST v1.1 in cohort A-CD. Secondary endpoints included ORR in cohorts A-ID and B, duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: Overall, 260 patients were enrolled and treated (A-CD, n = 101; A-ID, n = 103; B, n = 44; unconfirmed FGF/FGFR status, n = 12). All discontinued treatment, most commonly due to progressive disease (68.5%). ORR [95% confidence interval (CI)] in cohorts A-CD and A-ID was 17.8% (10.9% to 26.7%) and 23.3% (15.5% to 32.7%), respectively. Among patients with the most common FGFR3 mutation (S249C; n = 107), ORR was similar between cohorts (A-CD, 23.9%; A-ID, 24.6%). In cohorts A-CD/A-ID, median (95% CI) DOR was 6.2 (4.1-8.3)/6.2 (4.6-8.0) months, PFS was 4.0 (3.5-4.2)/4.3 (3.9-6.1) months, and OS was 6.8 (5.3-9.1)/8.9 (7.5-15.2) months. Pemigatinib had limited clinical activity among patients in cohort B. Of 36 patients with samples available at progression, 6 patients had 8 acquired FGFR3 secondary resistance mutations (V555M/L, n = 3; V553M, n = 1; N540K/S, n = 2; M528I, n = 2). The most common treatment-emergent adverse events overall were diarrhea (44.6%) and alopecia, stomatitis, and hyperphosphatemia (42.7% each). CONCLUSIONS: Pemigatinib was generally well tolerated and demonstrated clinical activity in previously treated, unresectable or metastatic UC with FGFR3 mutations or fusions/rearrangements.


Asunto(s)
Antineoplásicos , Carcinoma de Células Transicionales , Morfolinas , Pirimidinas , Pirroles , Neoplasias de la Vejiga Urinaria , Humanos , Adolescente , Carcinoma de Células Transicionales/tratamiento farmacológico , Antineoplásicos/efectos adversos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Genómica
7.
Ann Oncol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38964714

RESUMEN

BACKGROUND: Neoadjuvant short-course radiotherapy (SCRT) followed by CAPOX and camrelizumab (a programmed cell death protein 1 monoclonal antibody) has shown potential clinical activity for locally advanced rectal cancer (LARC) in a phase II trial. This study aimed to further confirm the efficacy and safety of SCRT followed by CAPOX and camrelizumab compared to long-course chemoradiotherapy (LCRT) followed by CAPOX alone as neoadjuvant treatment for LARC. PATIENTS AND METHODS: In this randomized, phase III trial, patients with T3-4/N+ rectal adenocarcinoma were randomly assigned (1 : 1) to receive SCRT or long-course chemoradiotherapy (LCRT), followed by two cycles of camrelizumab and CAPOX or CAPOX alone, respectively. After surgery, each arm underwent either six cycles of camrelizumab and CAPOX, followed by up to 17 doses of camrelizumab, or six cycles of CAPOX. The primary endpoint was pathological complete response (pCR) rate (ypT0N0) assessed by a blinded independent review committee. Key secondary endpoints tested hierarchically were 3-year event-free survival (EFS) rate and overall survival (OS). RESULTS: Between July 2021 and March 2023, the intention-to-treat population comprised 113 patients in the experimental arm and 118 patients in the control arm, with surgery carried out in 92% and 83.9%, respectively. At data cut-off (11 July 2023), the pCR rates were 39.8% [95% confidence interval (CI) 30.7% to 49.5%] in the experimental arm compared to 15.3% (95% CI 9.3% to 23.0%) in the control arm (difference, 24.6%; odds ratio, 3.7; 95% CI 2.0-6.9; P < 0.001). In each arm, surgical complication rates were 40.0% and 40.8%, and grade ≥3 treatment-related adverse events were 29.2% and 27.2%. Three-year EFS rate and OS continue to mature. CONCLUSIONS: In LARC patients, neoadjuvant SCRT followed by camrelizumab plus CAPOX demonstrated a significantly higher pCR rate than LCRT followed by CAPOX, with a well-tolerated safety profile. SCRT followed by camrelizumab and chemotherapy can be recommended as a neoadjuvant treatment modality for these patients.

8.
J Synchrotron Radiat ; 31(Pt 1): 35-41, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38084592

RESUMEN

In X-ray diffraction measurements, the angular resolution has a detection limit due to the receiving size of the detector. In many cases this detection limit is too large and must be breached to obtain the desired information. A novel method is proposed here by making the detector simultaneously measuring and moving. Using the deconvolution algorithm to remove the convolution effect, the pixel size limitation is finally broken. The algorithm used is not a common one, and suppresses signals at high frequencies, ensuring the reliability of the peak shape after restoration. The feasibility of this method is verified by successfully measuring the crystal truncation rod signal of SrTiO3 single crystal, and the resolution is nearly ten times higher than that of a single pixel. Moreover, this method greatly reduces the noise and improves the signal-to-noise ratio.

9.
Phys Rev Lett ; 132(5): 056002, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364146

RESUMEN

We investigated the high energy spin excitations in electron-doped La_{2-x}Ce_{x}CuO_{4}, a cuprate superconductor, by resonant inelastic x-ray scattering (RIXS) measurements. Efforts were paid to disentangle the paramagnon signal from non-spin-flip spectral weight mixing in the RIXS spectrum at Q_{∥}=(0.6π,0) and (0.9π,0) along the (1 0) direction. Our results show that, for doping level x from 0.07 to 0.185, the variation of the paramagnon excitation energy is marginal. We discuss the implication of our results in connection with the evolution of the electron correlation strength in this system.

10.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38728703

RESUMEN

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

11.
Philos Trans A Math Phys Eng Sci ; 382(2273): 20230197, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38736334

RESUMEN

The origin of micrometeorites (MMs) from asteroids and comets is well-established, but the relative contribution from these two classes remains poorly resolved. Likewise, determining the precise origin of individual MMs is an open challenge. Here, cosmic-ray exposure ages are used to resolve the spatial origins of 12 MMs collected from urban areas and Antarctica. Their 26Al and 10Be concentration, produced during cosmic-ray irradiation in space, were measured by accelerator mass spectrometry. These data are compared to results from a model simulating the transport and irradiation of the MM precursors in space. This model, for the first time, considers a variety of orbits, precursor particle sizes, compositions and densities and incorporates non-isotropic solar and galactic cosmic-ray flux profiles, depth-dependent production rates, as well as spherical evaporation during atmospheric entry. While the origin for six MMs remains ambiguous, two MMs show a preferential tendency towards an origin in the Inner Solar System (Near Earth Objects to the Asteroid Belt) and four towards an origin in the Outer Solar System (Jupiter Family Comets to the Kuiper Belt). These findings challenge the notion that dust originating from the Outer Solar System is unlikely to survive long-term transport and delivery to the terrestrial planets. This article is part of the theme issue 'Dust in the Solar System and beyond'.

12.
Phys Chem Chem Phys ; 26(20): 14930-14936, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38738788

RESUMEN

The unique 4f orbitals and abundant electronic energy levels of rare earth elements enable effective doping and modification to enhance hydrogen storage performance, making it an increasingly prominent focus of research. The structures of neutral and cationic CeHn0/+ (n = 2-20) clusters have been determined using the Crystal Structure AnaLYsis by Particle Swarm Optimization (CALYPSO) method in conjunction with density functional theory (DFT). Interestingly, the CeH13 and CeH14+ exhibit remarkable stability in the doublet state with Cs and C2v symmetry, respectively. The adsorption energy of CeHn0/+ (n = 2-20) suggests a preference for H atoms to chemically adsorb on Ce atoms. The analysis of molecular orbital composition reveals that the stability of both CeH13 and CeH14+ is attributed to the significant hybridization between the H 1s and Ce 4f orbitals. Both CeH13 and CeH14+ demonstrate significant hydrogen storage capacities, with values reaching 8.5 wt% and 9.1 wt%, respectively.

13.
Clin Radiol ; 79(6): 420-427, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599950

RESUMEN

AIM: To examine the relationship between fasting prior to contrast-enhanced CT (CECT) and adverse reaction (AR) in patients with allergies history. MATERIALS AND METHODS: Patients with allergies history who underwent CECT from January 2014 to December 2020 (713 cases with iodinated contrast media (ICM)-related allergy history and 27045 cases with unrelated allergies history) were retrospectively analyzed. The occurrence of ICM-related AR and patient information were recorded. The relationship between fasting and AR and emetic complications was analyzed. RESULTS: There was no statistical difference in the overall incidence of AR and emetic complications between fasting group and non-fasting group (P>0.05) and fasting was not an influence factor for overall AR occurrence in patients with both ICM-related and unrelated allergies history. However, the incidence of severe AR in fasting group was higher than that in non-fasting group (P=0.01) in patients with unrelated allergies history. The AR incidence in fasting group was higher than that in non-fasting group (P=0.022) when receiving abdominal examinations in patients with unrelated allergies history. There was no statistical difference in the incidence of AR with different occurrence time between fasting group and non-fasting group (P>0.05) in patients with both ICM-related and unrelated allergies history. CONCLUSIONS: Fasting was associated with higher incidence of severe AR and was associated with higher AR incidence when receiving abdominal examinations in patients with unrelated allergies history. Fasting did not have effects on the occurrence time of AR in patients with allergies history. These provided new guidance for usage of ICM in patients with allergies history.


Asunto(s)
Medios de Contraste , Ayuno , Tomografía Computarizada por Rayos X , Humanos , Medios de Contraste/efectos adversos , Femenino , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Anciano , Adulto , Hipersensibilidad a las Drogas/epidemiología , Incidencia , Anciano de 80 o más Años , Hipersensibilidad , Adolescente , Adulto Joven
14.
Clin Radiol ; 79(3): 205-212, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38218705

RESUMEN

AIM: To explore the utility of the 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in the differential diagnosis of IgG4-related lymphadenopathy (IgG4-RLAD) and angioimmunoblastic T-cell lymphoma (AITL). MATERIALS AND METHODS: Retrospective analysis of 18F-FDG PET/CT imaging findings in clinically diagnosed IgG4-RLAD and AITL cases was undertaken to record the distribution, morphological characteristics, and imaging features of the affected lymph nodes, as well as FDG uptake of the spleen and bone marrow. Standardised uptake values normalised to lean body mass were evaluated for maximum (SULmax), average (SULavg), and peak values (SULpeak). Univariate and multivariate logistic regression was used to screen for statistically significant imaging findings to discriminate IgG4-RLAD from AITL. RESULTS: Twenty-two cases of IgG4-RLAD (17 men, five women, median age 49.5 years) and 22 cases of AITL (16 men, six women, median age 55 years) were finally included in the analysis. There were no AITL patients with involvement of a single lymph node region. AITL patients had more involvement of the different nodal regions except cervical and pelvic nodal regions. A practical assessment method based on a combination of SULpeak-LN/SULavg-liver, SULpeak-spleen, and the number of involved nodal regions, improved the performance for differential diagnosis between both groups with an overall classification accuracy of 90.9%. CONCLUSIONS: 18F-FDG PET/CT is a useful tool for distinguishing AITL from IgG4-RLAD, and it can also help determine the optimal biopsy site for suspected cases of IgG4-RLAD or AITL, reduce the need for re-biopsy procedures, and enable physicians to develop timely treatment strategies.


Asunto(s)
Linfadenopatía , Linfoma de Células T , Masculino , Humanos , Femenino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Estudios Retrospectivos , Diagnóstico Diferencial , Inmunoglobulina G , Linfadenopatía/diagnóstico por imagen , Linfoma de Células T/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Radiofármacos
15.
Clin Radiol ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39025718

RESUMEN

AIM: Compare the T1 mapping, fat fraction, diffusion and perfusion parameters of the lumbar vertebrae of different age groups to establish normal values for healthy children and observe the trends in these parameters with age. MATERIALS AND METHODS: A total of 146 healthy children (0-14 years) were included in this prospective study and underwent 3.0 T lumbar MRI examination. The study cohort was divided into five age groups (Group A âˆ¼ E) according to development milestones in children. T1 mapping, Dixon and IVIM (intravoxel incoherent motion)sequence images were used to measure the parameters of lumbar vertebrae 2-4. RESULTS: The normal values of each parameter were measured and compared across different age groups. The T1 value was negatively correlated with age (r=-0.619, p<0.001). The fat fraction (FF%) was positively correlated with age (r=0.635, p<0.001). There was a negative correlation between the D value and age (r=-0.406, p<0.001). The D∗ value was positively correlated with age (r=0.54, p<0.001). The f value was positively correlated with age (r=0.775, p<0.001). The inflexion points of the T1 value and FF% curves were at approximately 3 years old (36 months).The inflexion points of the IVIM-related parameter curves were approximately 5 years old (60 months). CONCLUSION: The age-dependent differences in the vertebral body parameters of this pediatric cohort suggest changes in the bone marrow composition and cellular structure of the vertebral body during physiological growth in children. The establishment of normal values of children's lumbar spine can facilitate the clinical study of diseases.

16.
Clin Radiol ; 79(9): e1101-e1107, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38890050

RESUMEN

AIMS: Synchronous multiple pure ground-glass opacities (SMpGGOs) are observed more commonly. Nevertheless whether characteristics of SMpGGOs are similar to those of solitary pure ground-glass opacities (SpGGOs), remains unknown. This retrospective study aimed to compare radiographic characteristics between SMpGGOs and SpGGOs. MATERIALS AND METHODS: We retrospectively included patients along with SpGGOs or SMpGGOs at XXX between August 2018 and June 2020. They were enrolled in two groups (SpGGOs and SMpGGOs). The clinical records, pathologic features, and radiographic manifestations of two groups were collected and compared with SPSS 21.0. RESULTS: 138 patients (58 patients with 58 SpGGOs, 80 patients with 187 SMpGGOs) were evaluated. The threshold values of maximal diameters and mean computed tomography value for adenocarcinoma were 5.5 mm (sensitivity 86.4%, specificity 55.6%, AUC 0.777) and -615.0 Hu in SMpGGOs (sensitivity 61.4%, specificity 66.7%, AUC 0.651) for SMpGGOs, whereas 12.5 mm (sensitivity 54.5%, specificity 100%, AUC 0.851) and -531.9 Hu (sensitivity 43.2%, specificity 100%, AUC 0.724) in SpGGOs. CONCLUSION: The threshold values of maximal diameters and mean computed tomography value for adenocarcinoma in SMpGGOs may be smaller than those in SpGGOs (5.5 mm vs. 12.5mm, -615.0 Hu vs. -531.9 Hu).


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Tomografía Computarizada por Rayos X/métodos , Adenocarcinoma del Pulmón/diagnóstico por imagen , Adenocarcinoma del Pulmón/patología , Anciano , Sensibilidad y Especificidad , Pulmón/diagnóstico por imagen , Pulmón/patología , Adulto
17.
Clin Radiol ; 79(7): 501-514, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38670918

RESUMEN

AIM: The objective of this study is to explore the diagnostic value of machine learning (ML) in borderline ovarian tumors through meta-analysis. METHODS: Pubmed, Embase, Web of Science, and Cochrane Library databases were comprehensively retrieved from database inception untill February 16, 2023. The Prediction Model Risk of Bias Assessment Tool (PROBAST) was adopted to evaluate the risk of bias in the original studies. Sub-group analyses of ML were conducted according to clinical features and radiomics features. We separately discussed the discriminative value of ML for borderline vs benign and borderline vs malignant tumors. RESULTS: Eighteen studies involving 12,778 subjects were included in our analysis. The modeling variables mainly consisted of radiomics features (n=13) and a small number of clinical features (n=5). When distinguishing between borderline and benign tumors, the ML model based on radiomic features achieved a c-index of 0.782 (95% CI: 0.732-0.831), sensitivity of 0.75 (95% CI: 0.67-0.82), and specificity of 0.75 (95% CI: 0.67-0.81) in the validation set. When distinguishing between borderline and malignant tumors, the ML model based on radiomic features achieved a c-index of 0.916 (95% CI: 0.891-0.940), sensitivity of 0.86 (95% CI: 0.78-0.91), and specificity of 0.88 (95% CI: 0.82-0.92) in the validation set. In addition, we analyzed the discriminatory ability of radiologists and found that their sensitivity was 0.26 (95% CI: 0.12-0.46) and specificity was 0.94 (95% CI: 0.90-0.97). CONCLUSIONS: ML has tremendous potential in the preoperative diagnosis and differentiation of borderline ovarian tumors and may be more accurate than radiologists in diagnosing and differentiating borderline ovarian tumors.


Asunto(s)
Aprendizaje Automático , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/diagnóstico por imagen , Sensibilidad y Especificidad , Ovario/diagnóstico por imagen , Diagnóstico Diferencial , Reproducibilidad de los Resultados
18.
Clin Radiol ; 79(1): e189-e195, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37949801

RESUMEN

AIM: To report the authors' experience of bronchial artery embolisation (BAE) in a series of patients to control haemoptysis associated with infected pulmonary artery pseudoaneurysms (PAPs). MATERIALS AND METHODS: All patients who underwent BAE based on computed tomography angiography (CTA) findings indicative of haemoptysis between February 2019 and September 2022 at Xiangyang Central Hospital were identified. Charts of patients with haemoptysis and infectious PAPs were reviewed retrospectively. Data were collected data on age, sex, underlying pathology, source pulmonary artery of the PAP, association with cavitary lesions or consolidation, systemic angiography findings, technical and clinical success, and follow-up. RESULTS: Seventeen PAPs were treated in 16 patients, with a mean age of 60.3 years (range: 37-82 years). The most common underlying cause was tuberculosis (15/16, 93.8%). Imaging by CTA did not identify the source pulmonary artery for 15 (88.2%) PAPs; all were associated with cavitary lesions or consolidation. All PAPs were visualised on systemic angiography. The technical and clinical success rates were both 87.5%. Two patients who experienced a recurrence of haemoptysis during follow-up underwent repeat CTA, which confirmed the elimination of the previous PAP. CONCLUSION: BAE may be a valuable technique to control haemoptysis associated with infectious PAPs that are visualised on systemic angiography. A possible contributing factor is PAPs arising from very small pulmonary arteries.


Asunto(s)
Aneurisma Falso , Embolización Terapéutica , Humanos , Persona de Mediana Edad , Arteria Pulmonar/diagnóstico por imagen , Aneurisma Falso/complicaciones , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/terapia , Estudios Retrospectivos , Hemoptisis/diagnóstico por imagen , Hemoptisis/etiología , Hemoptisis/terapia , Angiografía/métodos , Arterias Bronquiales/diagnóstico por imagen , Embolización Terapéutica/métodos , Resultado del Tratamiento
19.
Clin Radiol ; 79(5): 363-370, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38290939

RESUMEN

AIM: To compare 1-year outcomes of computed tomography venography (CTV) combined with ultrasound-guided minimally invasive treatment with ascending phlebography and ultrasound-guided treatment for recurrent varicose veins. MATERIALS AND METHODS: Consecutive patients with unilateral recurrent varicose veins were matched by gender, age, C classification, and degree of obesity, and randomised in a 1:1 ratio to receive either CTV (CTV group) or ascending phlebography (control group) combined with ultrasound-guided minimally invasive treatment. Patients were followed up by clinical and ultrasound examination. Follow-up was scheduled at 1 week, and 3, 6, and 12 months. The primary outcome measure was the Venous Clinical Severity Score (VCSS) at 12 months. Measures of secondary outcome included Chronic Insufficiency Venous International Questionnaire-20 (CIVIQ-20) score, recurrence of varicose vein or ulcer during 12 months, ulcer healing time, detection and location of treated veins. RESULTS: Eighty patients were enrolled. Median VCSS in the CTV group was lower than it in the control group (p=0.04) and the CIVIQ-20 score was higher than the control group (p=0.02). By 12 months, no symptomatically recurrent varicose veins or ulcers had occurred. The ulcer healing time in CTV group was shorter (p<0.01). A greater number of patients had treated veins detected using CTV than by ascending venography (p=0.01), especially among patients with recurrence reflux veins in the groin, perineum, and vulva (p<0.01). CONCLUSION: CTV combined with ultrasound may be more helpful than ascending phlebography combined with ultrasound to improve treatment efficacy for recurrent varices. These results should be verified by an future study with more patients and long-term follow-up.


Asunto(s)
Úlcera , Várices , Femenino , Humanos , Flebografía/métodos , Recurrencia Local de Neoplasia , Várices/diagnóstico por imagen , Várices/cirugía , Resultado del Tratamiento , Tomografía Computarizada por Rayos X , Ultrasonografía Intervencional
20.
Clin Radiol ; 79(2): e282-e286, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38087682

RESUMEN

AIM: To assess changes in the susceptibility of the caudate nucleus (CN), putamen, and globus pallidus (GP) in patients with neurological and hepatic Wilson's disease (WD) by quantitative susceptibility mapping (QSM). MATERIAL AND METHODS: The brain MRI images of 33 patients diagnosed with WD and 20 age-matched controls were analysed retrospectively. All participants underwent brain T1-weighted, T2-weighted, and QSM imaging using a 1.5 T magnetic resonance imaging (MRI) machine. QSM maps were evaluated with the STISuite toolbox. The quantitative susceptibility levels of the CN, putamen, and GP were analysed using region of interest analysis on QSM maps. Differences among neurological WD patients, hepatic patients, and controls were determined. RESULTS: Susceptibility levels were significantly higher for all examined structures (CN, putamen and GP) in patients with neurological WD compared with controls (all p<0.05) and hepatic WD patients (all p<0.05). No statistically significant differences were found in susceptibility levels between patients with hepatic WD and controls (all p>0.05). CONCLUSION: The QSM technique is a valuable tool for detecting changes in brain susceptibility in WD patients, indicating abnormal metal deposition. Notably, the current findings suggest that neurological WD patients exhibit more severe susceptibility changes compared with hepatic WD patients. Therefore, QSM can be utilised as a complementary method to detect brain injury in WD patients.


Asunto(s)
Degeneración Hepatolenticular , Humanos , Degeneración Hepatolenticular/diagnóstico por imagen , Degeneración Hepatolenticular/patología , Estudios Retrospectivos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos
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