Monitoring vascular perfusion of transferred tissue is essential in reconstructive surgery to recognize early flap failure. The aim of this study was to evaluate the ability of a digital surface scanner to detect vascular perfusion disorders through the monitoring of skin colour changes. A total of 160 surface scans of the forearm skin were performed with a TRIOS 3D scanner. Vascular compromise was simulated at different time-points by intermittent occlusion of the blood supply to the forearm skin (first the arterial blood supply and then the venous blood supply). Skin colour changes were examined according to the hue, saturation, and value colour scale. Colour differences were analysed with a paired t-test. Significant differences were observed between the colour of the normal skin and that of the vascular compromised skin (P < 0.01). The surface scanner could distinguish between arterial occlusion and venous congestion (P < 0.01). A digital surface scan is an objective, non-invasive tool to detect early vascular perfusion disorders of the skin. 相似文献
This position paper was intended to update the former consensus between the French Societies of Radiology and Cardiology about the use of stress cardiac magnetic resonance imaging (MRI) in chronic coronary syndrome published in 2009. The Delphi method was used to build the present consensus. This expert panel consensus includes recommendations for indications, procedure with patient preparation, stress inducing drugs, acquisition protocol, interpretation and risk stratification by stress MRI. 相似文献
Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength. 相似文献
Purpose: Although hyperhomocysteinemia (Hhcy) is a risk factor for cerebral infarction, its effect on recurrent cerebral infarction is less-defined. We aimed to investigate the association of Hhcy and increased risk of recurrent cerebral infarct.
Materials and methods: From 2011 to 2013, we recruited 231 primary cerebral infarct patients that were divided to a Hhcy group (n?=?105) and a control group (n?=?126) according to plasma homocysteinemia (Hcy) levels exceeding 15?μmol/L. In this prospective study, risk factors such as gender, age, blood lipid and glucose levels, history of diabetes, high blood pressure, smoking habits and plasma Hhcy levels were determined. A three-year follow-up compared differences in cerebral infarction recurrence rates. Statistical analyses identified whether plasma Hhcy levels were an independent risk factor for recurrent cerebral infarction.
Results: Triglyceride and low-density lipoprotein (LDL) levels in the Hhcy group were significantly higher than controls, and cerebral infarct recurrence rates in the Hhcy group exceeded control subject rates through the three-year follow-up (p?=?.021, p?=?.036 and p?=?.025). Cox proportional hazards modeling showed that elevated Hhcy levels (hazard ratio [HR]?=?3.062, p?<?.001), increased age (HR?=?1.069, p?<?.01), circulating triglyceride levels (HR?=?1.686, p?=?.048), and relative National Institutes of Health Stroke (NIHSS) score (HR?=?1.068, p?=?.016) were risk factors for recurrent cerebral infarction.
Conclusions: Level of Hhcy was a risk factor for recurrent cerebral infarction. Further, particular demographic and clinical outcomes including age, relative NIHSS scores, and circulating triglyceride levels were markedly associated with the occurrence of cerebral infarction. 相似文献
Sudden death in childhood and adolescence is fortunately rare. However, when it occurs, it can have a devastating effect on the family. Therefore, these cases should be thoroughly investigated, including a complete post mortem examination by a specialist in paediatric pathology. The aim is to identify the cause of death, and potentially prevent future deaths. This review will provide an overview of the epidemiology of sudden death in childhood and adolescence and will outline the wide range of causes of death identified. Certain aspects of the paediatric post mortem examination will be discussed, and will finish with a section on deaths in children with chronic medical conditions. 相似文献