Search results for " ULTRASOUND"
showing 10 items of 818 documents
Cardiac output following fetoscopic coagulation of major placental vessels in fetal sheep.
2008
Objectives To measure changes in cardiac output (CO) after partial cord occlusion in fetal sheep in order to investigate pathophysiological fetal adaptation mechanisms in a simulated acute placental insufficiency model under standardized conditions, with the aim of finding relevant methods for monitoring human fetuses during stress situations. Methods We used minimally invasive, percutaneous endoscopic techniques to close umbilical vessels in mid-gestational fetal sheep. Placental blood flow was reduced by preferentially closing first arterial and then the concomitant venous umbilical vessels within a short time interval. The investigations were carried out on 11 pregnant ewes at a median g…
Integrated non-invasive approach to atherosclerosis with cardiac CT and carotid ultrasound in patients with suspected coronary artery disease
2017
The aim of the study was to compare the atherosclerotic disease in the coronary and carotid arteries in patients who underwent non-invasive imaging for suspected stable coronary artery disease (CAD). 107 patients (64 men, age 59 ± 12) with atypical chest pain underwent cardiac CT (CCT) and carotid ultrasound (US) on the same day. Severity (obstructive or not-obstructive disease), location, shape, and composition of atherosclerotic plaques in the two districts were evaluated. Patients presented normal coronary arteries in 36 % (n = 38), not-obstructive CAD in 36 % (n = 39), and obstructive CAD in 28 % (n = 30), while had normal carotid arteries in 53 % (n = 57), not-obstructive disease in 44…
Vantaggi degli ultrasuoni nel posizionamento di un agocannula nella vena giugulare interna (nuove note di tecnica)
2004
The authors analized the result of 175 central venous ca he- terization CVC. of internal jugular vein performed with the ultrasound guide (US) from January 1998 to October 2002. The average performing time was 45 minutes. 98.2% of success and 4% of complications (one pagal hypotension, one artery puncture, four catheter dislocation, one haeiuatoinai). The US guide CVC is a safe procedure with short performing time, low rate of failures and complications and high rate of success: it is helpful in all patients with vascular anatomical variations, with not visualized or Land marks and with coagulation disorders.
One shoot seldinger central venous catheterization in dialyzed patients
2015
Introduction: Central Venous Catheterization is necessary in uremic patient (before dialysis) and many other conditions. In this study we demonstrated the advantages of ultrasonography to perform the procedure. Materials and methods: 48 uremic patient were submitted to ultrasound-guided central venous catheterization. The procedure was performed following the Seldinger “one shot” technique. Results: The mean operative time was 4 minutes, with a high rate of success (100%) and a low percentage of complications (2%). Conclusion: The ultrasound-guided central venous catheterization is a safe procedure, rapid and easy to perform. The procedure has a low rate of failures and complications and a …
Aluminium nitrate ceramics: a potential UV dosemeter material.
2002
The ceramic material AlN-Y 2 O 3 is proposed as a potential ultraviolet radiation (UVR) dosemeter using optically stimulated luminescence (OSL) and thermally stimulated luminescence (TL). Experimental studies have shown that AlN ceramics exhibit attractive characteristics suitable for practical UV dosimetry applications. The features are: (1) the spectral sensitivity covers the 200-350 nm range, in the UV-B region it is similar to that of human skin; (2) the angular dependence of the incident radiation follows the cosine law; (3) high yields of both UVR-induced OSL and TL signals compared to those of Al 2 O 3 :C; and (4) a large dynamic range TL signal (5 orders of magnitude). Although ther…
FMRI of the Cerebellum: Rostral Paravermal Activation in Tongue and Lip
1998
We investigated with fMRI the cerebellar representation of articulatory vertical movements of the tongue and orofacial muscles in healthy volunteers and its correspondence to the area known to be affected in cerebellar dysarthria. fMRI stimulation is mainly unilateral in agreement with the frequent occurrence of dysarthria in unilateral infarction.
Towards a unified analysis of brain maturation and aging across the entire lifespan: A MRI analysis
2017
Previous literature about the structural characterization of the human cerebellum is related to the context of a specific pathology or focused in a restricted age range. In fact, studies about the cerebellum maturation across the lifespan are scarce and most of them considered the cerebellum as a whole without investigating each lobule. This lack of study can be explained by the lack of both accurate segmentation methods and data availability. Fortunately, during the last years, several cerebellum segmentation methods have been developed and many databases comprising subjects of different ages have been made publically available. This fact opens an opportunity window to obtain a more extens…
Three-dimensional color power angiography of an aneurysm of the vein of Galen
2000
Channel Tracking Guidewire and Technique for Retrograde Approach
2020
Evaluation of the collateral circulation is critical for determining the feasibility of the retrograde approach. When assessing collateral channels it is of paramount importance to take time and review the previous angiogram carefully, for multiple potential collateral pathways, as the predominant collateral may change over time prior to the procedure. Careful review of collaterals prior to the procedure can reduce contrast and radiation dose as well as the duration of the procedure.Retrograde access to the distal vessel can be achieved via septal collaterals, epicardial collaterals (atrial channel), or (patent or occluded) coronary bypass grafts. Generally septals are used more often 65–70…