Fibrotic tissue

Sick sinus syndrome leading to sinus bradycardia occurs as a result of fibrotic tissue in the SA node, which replaces normal SA node tissue.12... 

Retroperitoneal fibrosis An accumulation of fibrotic tissues in the retroperitoneum (the anatomic space behind the abdominal cavity). Structures that lie behind the peritoneum are thus termed retroperitoneal. These structures include kidneys, the bladder, portions of the duodenum, portions of the colon, and the inferior vena cava. 

Cationized gelatin nanopar- ticle None Pol-III HI Intraureteral Obstructive C57BL/6 nephropa- mice thy Kidney TGF-p Reduction in collagen content and fibrotic tissue in the kidney interstitium (64, 81)... 

Fig. 8.15 Use of percutaneous transhepatic cholangiography in benign papillary stenosis. Hard fibrotic tissue after repeated passing of gallstones associated with colics over a period of three years. Treatment papillotomy...

In severe hepatic necrosis with large losses of parenchyma, the regenerating epithelium is not always able to restore the affected area completely. There is a development of fibrous bundles, which are in some places connected with pronounced and partly fringed fibrotic tissue in the portal field. Moreover, extensive cicatricial areas are formed, occasionally embedded in small parenchymal islets, (s. fig. 22.14)... 

Fibrosis is often a normal response to tissue injury where the damaged cells of an organ are unable to regenerate. An example of this is seen in the heart following myocardial infarction, where the infiircted tissue is replaced by a strong fibrous scar. However there are many pathological conditions where the development of fibrosis is detrimental. The fibrotic tissue response of chronic inflammation is often associated with increased numbers of mast cells, and has been most extensively studied in pulmonary fibrosis and systemic sclerosis. 

Jordana, M., Schulman, J., Me Sharry, C., Irving, L.B., Newhouse, M.T., Jordana, G. and Gauldie, J. (1988b). Heterogeneous proliferative characteristics of human adult lung fibroblast lines and clonally derived fibroblasts from control and fibrotic tissue. Am. Rev. Respir. Dis. 137, 579-584. 

Accumulation of both fibrillar and basement membrane-like collagens Increase of laminen and fibronectin Thickening of connective tissue septae Capillarization of the sinusoids Sclerosis Aging of fibrotic tissue... 

These hepatic cysts are thought to arise from dilatation of biliary microhamartomas (BMH). They demonstrate a cuboidal epithelial lining with the same histological appearance as that of the biliary epithelium, and may contain fluid. These lesions are generally smaller than 10 cm, surrounded by fibrotic tissue and localized close to the portal tracts (Suchy 2003). 

The need for safe extraction techniques, performed via the implant vein and compatible with the pectoral-pocket transvenous implant method, led to the development of transvenous percutaneous techniques [5, 6]. By using telescoping sheaths made of polymer and/or steel material that slide over the lead body, a countering force is applied to the intravascular fibrotic overgrowth that resists the traction force applied to the lead. This technique of intravascular counterpressure localizes shear stress on the fibrotic tissue and aids... 

Processed human umbilical veins are processed within 48 h of delivery according to a procedure developed by Dardik et oL A mandrel is insert into the lumen so as to straighten the vein which has no branches and to eliminate any constrictions formed between the Hoboken nodes. It is then fixed in either glutaraldehyde or a starch dialdehyde. Sometimes an external synthetic knitted mesh is added like a sleeve to reinforce the wall and provoke greater fibrotic tissue proliferation.The durability of the processed human umbilical vein has proven to be less than optimal lipid uptake and bacteremic colonization are typical postoperative complications. ... 

Modern endoscopes are based on Hopkin s optic system with variable diameter (minimum 1 mm in diameter), and length and angle variable on the basis of the region to explore. In the majority of cases the endoscopes are based on a rigid system, but in difficult cases, such as a strong curvature of the external auditory canal, the presence of stenosis or fibrotic tissue, the use of flexible endoscopes is preferred despite the lower spatial resolution and image quality. 

There are obviously some similarities between the development of fibrotic tissue in silicotic lungs and the development of atherosclerotic plaques in arteries. In both cases there is loss of elasticity and abnormal proliferation of one type of tissue. Also there is development of necrotic tissue. As pointed out by Benditt (296) the plaques were previously thought to consist of fibroblasts but have now been identified as smooth muscle cells. The growth of the plaque appears to involve a mutation that leads to proliferation of smooth muscle cells which thicken the artery wall and lead to necrosis within the plaque mass. Benditt cites possible agents of mutation as chemical mutagens, viruses, and ionizing radiations. 

Contrary to gadolinium-based and to iodinated contrast agents, microbubbles do not diffuse out of the blood circulation. As a consequence, after intravenous microbubble administration fibrotic tissue shows no enhancement in all vascular phases. At contrast-enhanced ultrasonography, localized cavernosal tissue fibrosis presents as a circumscribed perfusion defect. Diffuse fibrotic changes present with inhomogeneous enhancement ofthe corpora cavernosa. Contrary to the normal cavernosal tissue, delayed peripheral enhancement of variable degree is often appreciable, probably by the presence of viable subalbugineal cavernosal tissue fed by peripheral vascular pathways, while poor or no contrast enhancement is appreciable in the central portion of the corpora cavernosa (Fig. 21.10). 

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