Breast cancer is a major source of morbidity and mortality in the elderly population and the number of patients will increase by 30% in future decades. Surgery and endocrine therapy could be ...considered as the standard treatment in elderly breast cancer patients, but anaesthesia for surgery requires a specific approach taking into account physiological and psychological alterations secondary to ageing. In cases with major alterations of performance status, percutaneous radiofrequency ablation (RFA) could be substituted for the surgical treatment. The aim of the current study is to evaluate the efficacy and feasibility of this technique. Five tumours in four consecutive patients (aged 79-82 years) contraindicated for surgery with symptomatic cT1-2N0M0, positive oestrogen receptor status, low grade were treated by percutaneous radiofrequency-lump ablation under local analgesia, using percutaneous ultrasound guidance. Thermal lesions were produced with RF power 30 W, at a frequency of 500 kHz. Ultrasound-guided percutaneous biopsy of the RF treated breast was performed during the follow-up. We report a successful RFA lump ablation experience in the treatment of four tumours (4/5). One local recurrence occurred within 4 months after RFA. The other biopsies taken during the follow up showed all fat necrosis within the oil cyst and no malignant cells. One abscess occurred at 9 months within the treated area. After a mean follow up of 29.4 months, all the patients are still alive without any other signs of recurrence or metastases. Ultrasound-guided percutaneous RFA is safe and feasible in the management of breast cancer in elderly patients. Nevertheless, further large comparative studies are needed in order to validate such a minimally invasive procedure in current practice.
The present study is designed to evaluate and compare percutaneous radiologic arm port (R) and surgical subclavian port (S) devices in two homogeneous sets of breast cancer patients in terms of ...safety, efficacy, quality of life (QoL) and cost analysis.
This study involved a retrospective review of a prospective databank including 200 consecutive port device implantation attempted procedures performed over a 4-year period, in two similar groups of 100 breast cancer women who underwent either the surgical cephalic vein cutdown approach or the percutaneous basilic vein catheterization for intravenous adjuvant chemotherapy. Parameters analyzed included technical success, procedure duration, complications, QoL and cost evaluation for both techniques.
The success rate for port implantation was higher for R than for S placement (96% versus 91%). Mean implant duration time was 5.6 and 7.6 months for R and S, respectively. The overall complication rate was 10 and 16% for R and S, respectively. Mean implant duration time, without any complication or death, was 6.4 and 7.8 months for R and S, respectively. Six and seven percent for R and S, respectively, had to be removed prematurely. Both techniques exhibited very good QoL. Direct costs were respectively euro 230.8 and 219.1 for R and S, respectively.
The significant advantages of R over S include higher success rate, higher cosmetic results despite a 15% relative overcost for R placement. Both are indicated for breast cancer chemotherapy treatment, nevertheless R placement is mandatory in anxious patients who fear surgery, in case of previous cervico-thoracic irradiation or upper extremity venous thrombosis, or in patients at risk of respiratory insufficiency.
Context.A complex environment exists in the inner few astronomical units of planet-forming disks. High-angular-resolution observa-tions play a key role in our understanding of the disk structure and ...the dynamical processes at work.Aims.In this study we aim to characterize the mid-infrared brightness distribution of the inner disk of the young intermediate-massstar HD 163296 from early VLTI/MATISSE observations taken in theL- andN-bands. We put special emphasis on the detection ofpotential disk asymmetries.Methods.We use simple geometric models to fit the interferometric visibilities and closure phases. Our models include a smoothedring, a flat disk with an inner cavity, and a 2D Gaussian. The models can account for disk inclination and for azimuthal asymmetriesas well. We also perform numerical hydrodynamical simulations of the inner edge of the disk.Results.Our modeling reveals a significant brightness asymmetry in theL-band disk emission. The brightness maximum of the asym-metry is located at the NW part of the disk image, nearly at the position angle of the semimajor axis. The surface brightness ratio inthe azimuthal variation is3.5±0.2. Comparing our result on the location of the asymmetry with other interferometric measurements,we confirm that the morphology of ther<0.3au disk region is time-variable. We propose that this asymmetric structure, located in ornear the inner rim of the dusty disk, orbits the star. To find the physical origin of the asymmetry, we tested a hypothesis where a vortexis created by Rossby wave instability, and we find that a unique large-scale vortex may be compatible with our data. The half-lightradius of theL-band-emitting region is0.33±0.01au, the inclination is52◦+5◦−7◦, and the position angle is143◦±3◦. Our models predictthat a non-negligible fraction of theL-band disk emission originates inside the dust sublimation radius forμm-sized grains. Refractorygrains or large (&10μm-sized) grains could be the origin of this emission.N-band observations may also support a lack of smallsilicate grains in the innermost disk (r.0.6au), in agreement with our findings fromL-band data.
First light for GRAVITY Wide Abuter, R.; Allouche, F.; Amorim, A. ...
Astronomy and astrophysics (Berlin),
09/2022, Volume:
665
Journal Article
Peer reviewed
Open access
GRAVITY+ is the upgrade for GRAVITY and the Very Large Telescope Interferometer (VLTI) with wide-separation fringe tracking, new adaptive optics, and laser guide stars on all four 8 m Unit Telescopes ...(UTs) to enable ever-fainter, all-sky, high-contrast, milliarcsecond interferometry. Here we present the design and first results of the first phase of GRAVITY+, known as GRAVITY Wide. GRAVITY Wide combines the dual-beam capabilities of the VLTI and the GRAVITY instrument to increase the maximum separation between the science target and the reference star from 2 arcseconds with the 8 m UTs up to several 10 arcseconds, limited only by the Earth’s turbulent atmosphere. This increases the sky-coverage of GRAVITY by two orders of magnitude, opening up milliarcsecond resolution observations of faint objects and, in particular, the extragalactic sky. The first observations in 2019–2022 include the first infrared interferometry of two redshift
z
~ 2 quasars, interferometric imaging of the binary system HD 105913A, and repeat observations of multiple star systems in the Orion Trapezium Cluster. We find the coherence loss between the science object and fringe-tracking reference star well described by the turbulence of the Earth’s atmosphere. We confirm that the larger apertures of the UTs result in higher visibilities for a given separation due to the broader overlap of the projected pupils on the sky and provide predictions for visibility loss as a function of separation to be used for future planning.
Aims. In the context of the future developments of long baseline interferometry at visible wavelengths, we have built a prototype instrument called Fibered spectrally Resolved Interferometer – New ...Design (FRIEND) based on single mode fibers and a new generation detector called Electron Multiplying Charge-Coupled Device (EMCCD). Installed on the Center for High Angular Resolution Astronomy (CHARA) array, it aims to estimate the performance of a fibered instrument in the visible when coupled with telescopes equipped with adaptive optics (AO) in partial correction. Methods. We observed different sequences of targets and reference stars to study the compensation of the birefringence of the fibers, the coupling efficiency in various conditions of correction, and to calibrate our numerical model of signal-to-noise ratio (S/N). We also used a known binary star to demonstrate the reliability and the precision of our squared visibility and closure phase measurements. Results. We firstly present a reliable and stable solution for compensating the birefringence of the fibers with an improvement of a factor of 1.5 of the instrumental visibility. We then demonstrate an improvement by a factor of between 2.5 and 3 of the coupling efficiency when using the LABAO systems in closed loop. The third results of our paper is the demonstration of the correct calibration of the parameters of our S/N estimator provided the correct excess noise factor of EMCCD is correctly taken into account. Finally with the measurements of the angular separation, difference of magnitude and individual diameters of the two components of ζ Ori A, we demonstrate the reliability and precision of our interferometric estimators, and in particular a median residual on the closure phase of 1.2°.
Context.
The nature of circumstellar envelopes (CSEs) around Cepheids is a matter of ongoing debate. The physical origin of their infrared (IR) excess could be shown to either be made up of a shell ...of ionized gas, a dust envelope, or a combination of both.
Aims.
This study is aimed at constraining the geometry and the IR excess of the environment of the bright long-period Cepheid
ℓ
Car (
P
= 35.5 days) at mid-IR wavelengths in order to understand its physical nature.
Methods.
We first used photometric observations in various bands (from the visible domain to the infrared) and
Spitzer
Space Telescope spectroscopy to constrain the IR excess of
ℓ
Car. Then we analyzed the VLTI/MATISSE measurements at a specific phase of observation in order to determine the flux contribution as well as the size and shape of the environment of the star in the
L
band. Finally, we tested the hypothesis of a shell of ionized gas in order to model the IR excess.
Results.
We report the first detection in the
L
band of a centro-symmetric extended emission around
ℓ
Car, of about 1.7
R
⋆
in full width at half maximum, producing an excess of about 7.0% in this band.This latter value is used to calibrate the IR excess found when comparing the photometric observations in various bands and quasi-static atmosphere models. In the
N
band, there is no clear evidence for dust emission from VLTI/MATISSE correlated flux and
Spitzer
data. On the other side, the modeled shell of ionized gas implies a more compact CSE (1.13 ± 0.02
R
⋆
) that is also fainter (IR excess of 1% in the
L
band).
Conclusions.
We provide new evidence supporting a compact CSE for
ℓ
Car and we demonstrate the capabilities of VLTI/MATISSE for determining common properties of CSEs. While the compact CSE of
ℓ
Car is likely to be of a gaseous nature, the tested model of a shell of ionized gas is not able to simultaneously reproduce the IR excess and the interferometric observations. Further Galactic Cepheid observations with VLTI/MATISSE are necessary for determining the properties of CSEs, which may also depend on both the pulsation period and the evolutionary state of the stars.
Context. The nature of circumstellar envelopes (CSEs) around Cepheids is a matter of ongoing debate. The physical origin of their infrared (IR) excess could be shown to either be made up of a shell ...of ionized gas, a dust envelope, or a combination of both. Aims. This study is aimed at constraining the geometry and the IR excess of the environment of the bright long-period Cepheid ℓ Car ( P = 35.5 days) at mid-IR wavelengths in order to understand its physical nature. Methods. We first used photometric observations in various bands (from the visible domain to the infrared) and Spitzer Space Telescope spectroscopy to constrain the IR excess of ℓ Car. Then we analyzed the VLTI/MATISSE measurements at a specific phase of observation in order to determine the flux contribution as well as the size and shape of the environment of the star in the L band. Finally, we tested the hypothesis of a shell of ionized gas in order to model the IR excess. Results. We report the first detection in the L band of a centro-symmetric extended emission around ℓ Car, of about 1.7 R ⋆ in full width at half maximum, producing an excess of about 7.0% in this band.This latter value is used to calibrate the IR excess found when comparing the photometric observations in various bands and quasi-static atmosphere models. In the N band, there is no clear evidence for dust emission from VLTI/MATISSE correlated flux and Spitzer data. On the other side, the modeled shell of ionized gas implies a more compact CSE (1.13 ± 0.02 R ⋆ ) that is also fainter (IR excess of 1% in the L band). Conclusions. We provide new evidence supporting a compact CSE for ℓ Car and we demonstrate the capabilities of VLTI/MATISSE for determining common properties of CSEs. While the compact CSE of ℓ Car is likely to be of a gaseous nature, the tested model of a shell of ionized gas is not able to simultaneously reproduce the IR excess and the interferometric observations. Further Galactic Cepheid observations with VLTI/MATISSE are necessary for determining the properties of CSEs, which may also depend on both the pulsation period and the evolutionary state of the stars.
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