Thrombus, tumor

There are a large number of papers proposing the internal use of nanocellulose, for example, as implants of the vascular system, carrier for drug delivery into the bloodstream, etc. A problem is that the human organism does not contain cellulolytic enzymes. Therefore it can be expected that the introduction of alien stable nanoparticles or nanofibrils into the internal body systems could cause a thrombus, tumor, or inflammatory or toxic response of the organism. Considering that the problem of nanosafety requires further study, here we will show mainly the external use of the nanocellulose, for example, for personal care, as a skin cure, etc. In some cases, the problem of biocompatibility will also be discussed. 

Deposition and adhesion of cells on surfaces play an important part in many biological processes. For example, blood cell deposition and adhesion on surfaces are essential in the vital process of haemostasis and fundamental in the events leading to thrombus formation. Also, malignant cell adhesion on various tissues is responsible for the growth of secondary tumors, after being carried in the blood stream from the primary tumor location. 

Left atrial thrombus Left atrial appendage thrombus Spontaneous echo contrast Intracardiac tumors Atrial septal defect ... 

Matsumoto, S., Mori, H., Takaki, H., Ishitobi, F., Sbuto, R., Yoko-yama, S. Malignant lymphoma with tumor thrombus in the portal venous system. Abdom. Imag. 2004 29 460—462... 

The biochemical alterations which provide malignant cells with the ability to invade adjacent tissues and to spread to other locations are poorly understood and are undoubtedly complex. This complexity manifests itself clearly in the process of metastasis, in which cells must go through a series of steps including tissue invasion, extravasation into blood vessels, thrombus formation, arrest, penetration through the wall of a lood vessel and growth, all in order to develop a secondary tumor. Each step of this sequence may require the precise temporal expression of specific biochemical functions, and some of these reactions, necessary for a step such as invasion, may be detrimental to other steps, such as the formation of a thrombus and arrest. 

Other uses of TEE include identification of cardiac thrombus, especially thrombi in the left atrium, and assessment of atrial dilation. After transient ischemic attacks or cerebrovascular accidents, TEE may enable identification of the site of cardiac emboli by providing excellent images of likely sources of such, namely, ventricular or atrial thrombus, valvular vegetation, cardiac shunts, cardiac tumors, or atrial and ventricular septal defects. In a study of almost 1500 patients with cerebral ischemia or nonvalvular atrial fibrillation, atrial thrombi were seen in 183 patients when evaluated by TEE versus only 2 patients using TTE. TEE can be used for intraoperative cardiac imaging to ascertain development of ischemia. 

In contrast to angiography, IVUS provides quantitative information from within the vessel on diameter, circumference, luminal diameter, plaque volume, and percent stenosis. Qualitative information regarding the amount of plaque elevation, plaque composition (e.g., calcific, fibrous, or fatty plaque), and the presence of plaque versus thrombus, thrombus versus tumor, and aneurysm and hematoma can be provided with IVUS. IVUS is also used as a therapeutic adjunct with PTCA, atherectomy, stent or graft placement, and fibrinolysis, although routine use may not be justified. These combination procedures may be monitored in real time as the procedure (e.g., atherectomy) is being performed. 

Atrial myxoma is a rare atrial tumor that causes multiple emboli of either thrombus or myxomatous tissue. When myxomatous material is embolized from the left atrium into the brain arteries, they may cause the formation of multiple distal cerebral aneurysms with risk of hemorrhage [46]. Papillary fibroelastomas are rare benign cardiac tumors usually involving a heart valve. They are small vascular growths with marked papillary projections. They usually grow on the aortic or mitral valves. The tumor consists of fibrous tissue surrounded by an elastic membrane, which in turn is covered by endothelium. One of the most conunon clinical presentations is of transient ischemic attack or stroke [47,48]. 

Lewandowski RJ, Alii A, Atassi B, Kulik L, Mulcahy MF, Salem R (2006) Retraction of portal vein thrombus following treatment with Y90 TheraSphere a secondary sign of tumor response. Society of Interventional Radiology 2006, Toronto, Canada... 

Basciano CA (2010) Computational particle-hemodynamics analysis applied to an abdominal aortic aneurysm with thrombus and microspheretargeting of liver tumors. Ph.D. dissertation. North Carolina State University, Department of Mechanical and Aerospace Engineering, Raleigh... 

An embolism occurs when a blood clot or thrombus is formed and released in an inflamed vein, associated with pain and swelling, which is called deep vein thrombosis (DVT). The releaised clot, called an embolus, is carried by the bloodsteam and causes an obstruction in a downstream blood vessel or capillary. An embolus can be either part of a thrombus, or an air bubble, piece of fat, bone marrow, or tumor tissue [3]. 

The use of Dacron-covered Gianturco-Rosch stents has been recommended to treat malignant SVC obstruction in patients with protrusion of tumor or thrombus trough the stent struts, which is a rare event (Chin et al. 1996). We have used Cragg stents in the past for these indications in a few patients. 

Fig. 30.6a-c. Extensive vascular involvement superior demonstration by CPR and VRT. a The axial image demonstrates a large cancer in the body and tail, with compression of the venous confluence, b The CPR image demonstrates the whole tumor (arrows) involving the celiac trunk and a thrombus (arrowhead) in the portal vein, c The volume-rendered image delineates extensive compression of the venous confluence (arrowhead) with subsequent thrombosis of the portal vein... 

MRI allows data acquisition with a very good soft tissue contrast and multiplanar image acquisition, especially in patients with extensive tumor with invasion of the inferior vena cava. MRI determines cranial extension of the thrombus much more effectively than does single-slice CT. Before the introduction of MDCT scanners, MRI used to be the image modality of choice for... 

Fig. 32.6. Extensive RCC with tirnior thrombus in the left distended renal vein (arrow). The extension of the tumor is difficult to define...

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