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Pituitary Apoplexy Following Systemic Anticoagulation
Get PDFPituitary apoplexy is a rare medico-surgical emergency that stems from an acute expansion of a pituitary adenoma from infarction or haemorrhage and where the treatment strategy is still controversial. Clinical presentation is highly variable and a high index of suspicion is needed to make the diagnosis. Furthermore, in less than half of cases, a precipitating event is identified. We report a case of a 74-year-old female who, after introduction of anticoagulation for pulmonary thromboembolism, presented with pituitary apoplexy heralded by acute adrenal insufficiency, headaches, visual symptoms and hypogonadotropic hypogonadism. Timely initiation of corticosteroids was crucial, and after stabilisation, a conservative treatment strategy was favoured with good long-term prognosis. Long-term follow-up of pituitary function also revealed new growth hormone deficiency
Moyamoya Syndrome after Radiation Therapy: a Clinical Report
Get PDFMoyamoya syndrome (MMS) is a rare, chronic and progressive vasculopathy with a characteristic angiographic pattern and well-recognized predisposing conditions, such as cranial therapeutic radiation. We report the case of a 36-year-old Caucasian female with a history of craniopharyngioma treated with whole-brain radiotherapy 20 years previously. She was admitted to the emergency department with disorientation and imperceptible speech lasting for 1 hour. Upon examination, she had slight motor aphasia, without sensory or motor deficits. However, the neurological deficits worsened on standing position. The computed tomography (CT) angiogram and transcranial Doppler ultrasonography revealed occlusion of the distal portion of the left internal carotid artery (ICA). Mechanical thrombectomy was attempted without success. Head CT was repeated, revealing left periventricular acute ischaemic stroke. The cerebral angiography showed total occlusion of the left ICA with an exuberant network of transdural collateral vessels, confirming MMS. The patient completed a functional rehabilitation program with progressive improvement of deficits and maintained a multidisciplinary follow-up. MMS is a serious late complication from cranial radiation therapy and a well-described risk factor for ischaemic stroke in younger patients. Therefore, early detection and prompt treatment are mandatory, as the consequences can be disastrous, such as cognitive and neurologic decline due to repeated strokes
A First Sign Not to be Missed: Cutaneous Metastasis from Breast Cancer
Get PDFCutaneous metastasis has a frequency of 1 to 10% among all metastatic cancer forms and breast cancer accounts for 30% of all cases. We report the case of a 73-year-old woman who presented with 4 skin lesions distributed across the upper trunk and abdomen; these had developed over a period of 12 months. Over the previous 6 months she had also developed anorexia, asthenia and weight loss. Upon investigation, a nodular mass was found in the left breast. Skin and breast mass biopsy were performed. Histology confirmed the diagnosis: infiltrating lobular breast cancer with cutaneous metastasis. The patient underwent hormonal treatment, mastectomy and radiotherapy.
In rare cases, cutaneous metastasis appears as the first clinical manifestation of breast cancer. It is therefore crucial for patients and health professionals alike to be aware of new skin lesions. Cutaneous metastasis is a diagnostic sign of cancer that, it must be emphasised, is not restricted exclusively to later forms of the disease
New atmosphere models to reconstruct solar irradiance
Get PDFWe aim at contributing to the refinement of the atmosphere models employed in solar irradiance reconstructions by deriving observation-based atmospheres from spectropolarimetric measurements of the solar atmosphere. Here we present results obtained from analysis of photospheric and chromospheric observations of quiet Sun, umbral, and penumbral regions, performed on May 20th 2016 with the IBIS Interferometric Bidimensional Spectrometer under excellent seeing conditions
Spectro-polarimetric analysis of a short lived solar active region
Get PDFThe physical processes related to the formation, evolution and disappearance of solar active regions are not completely clear. High-resolution solar spectro-polarimetric data are needed to investigate these processes with unprecedented details. Here we present the analysis of the short-lived NOAA 12549 active region using high-resolution spectro-polarimetric data acquired with the GREGOR solar telescope and the GRIS instrument, inverted using the SIR code
Spectral anisotropies in high resolution three-dimensional simulations
Get PDFWe present a 3D high resolution hybrid particle-in-cells simulation of decaying Alv´enic turbulence and we compare its results with an analogous simulations at MHD scales. We show that, while MHD simulations show spectral anisotropies in agreement with critical balance arguments, at ion scale magnetic spectrum is more isotropic than predicted. This suggest that intermittent smallscales structures, like reconnecting current sheets can play a fundamental role in transferring energy across kinetic scales
Observed and simulated coronal UV lines at solar minimum activity: The impact of the 3D tilted coronal streamer belt
Get PDFThe aim of this study is to improve the knowledge of the slow solar wind origin. In particular, we compute the emissivities and the intensities of UV spectral lines starting from the physical parameters of a time-dependent 3D three-fluid MHD model of the tilted coronal streamer belt. The results obtained from the model are compared in the extended corona (at 1.5 and 1.9 R�) to the UV spectroscopic data from the Ultraviolet Coronagraph Spectrometer (UVCS) onboard SOHO in the streamer belt during the minimum of solar activity (1996). The discussion is focused on the importance of the projection effects due to the integration along the line of sight in the coronal ultraviolet observations of streamer core dimming
Compressed sensing and Sequential Monte Carlo for solar hard X-ray imaging
Get PDFWe describe two inversion methods for the reconstruction of hard Xray solar images. The methods are tested against experimental visibilities recorded by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and synthetic visibilities based on the design of the Spectrometer/Telescope for Imaging X-rays (STIX)
Satellite observations of reconnection between emerging and pre-existing small-scale magnetic fields
Get PDFWe report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the unipolar plage of active region NOAA 12529. The photospheric configuration of the EFR is analyzed in detail benefitting from measurements taken with the spectropolarimeter aboard the Hinode satellite, when the EFR was fully developed. In addition, these data are complemented by full-disk, simultaneous observations of the SDO satellite, relevant to the photosphere and the corona. In the photosphere, magnetic flux emergence signatures are recognized in the fuzzy granulation, with dark alignments between the emerging polarities, cospatial with highly inclined fields. In the upper atmospheric layers, we identify recurrent brightenings that resemble UV bursts, with counterparts in all coronal passbands. These occur at the edges of the EFR and in the region of the arch filament system (AFS) cospatial to the EFR. Jet activity is also found at chromospheric and coronal levels, near the AFS and the observed brightness enhancement sites. The analysis of the IRIS line profiles reveals the heating of dense plasma in the low solar atmosphere and the driving of bi-directional high-velocity flows with speeds up to 100 km/s at the same locations. Furthermore, we detect a correlation between the Doppler velocity and line width of the Si IV 1394 and 1402 ˚A line profiles in the UV burst pixels and their skewness. Comparing these findings with previous observations and numerical models, we suggest evidence of several long-lasting, small-scale magnetic reconnection episodes between the emerging bipole and the ambient field. This process leads to the cancellation of a pre-existing photospheric flux concentration of the plage with the opposite polarity flux patch of the EFR. The reconnection appears to occur higher in the atmosphere than usually observed
Determination of the physical properties of an erupting prominence from SOHO/LASCO and UVCS observations
Get PDFWe studied the physical conditions of an erupting prominence observed in the core of a coronal mass ejection, using combination of SOHO/LASCOC2 visible-light images and SOHO/UVCS ultraviolet data. Measured intensities and profiles of the neutral-hydrogen Lyman-α and Lyman-β lines and the 977 ˚ACiii line were used together with the visible-light brightness to derive the geometrical and physical parameters of the prominence, such as the line-of-sight apparent thickness, electron column density, kinetic temperature, and microturbolent velocity. These parameters were used to constrain a non-LTE (i.e., out of local thermodynamic equilibrium) radiative-transfer model of the prominence that provides the effective thickness, electron density, and flow velocity, in a sample of points selected along the prominence. The prominence can be described as a hot structure with low electron density and very low gas pressure compared to typical quiescent prominences. Intensities of the hydrogen lines were also used for a detailed determination of the plasma line-of-sight filling factor, in the two prominence points where simultaneous and cospatial LASCO-C2 and UVCS observations were available