BackgroundProcess of accelerated atherosclerosis specific for uremia increases cardiovascular risk in patients with chronic kidney disease (CKD) and may be influenced by the different structure of arteries. The study assesses the influence of traditional and novel risk factors on calcification of coronary arteries (CAC) and abdominal aorta (AAC) in hemodialysis patients (HD).MethodsCAC and AAC were assessed by CT in 104 prevalent adult HD and 14 apparently healthy subjects with normal kidney function (control group). Mineral metabolism parameters, plasma levels of FGF-23, MGP, osteoprotegerin, osteopontin, fetuin-A, CRP, IL-6 and TNF-α were measured.ResultsCAC and AAC (calcification score ≥ 1) were found in 76 (73.1%) and 83 (79.8%) HD respectively, more frequent than in the control group. In 7 HD with AAC no CAC were detected. The frequency and severity of calcifications increased with age. Both CAC and AAC were more frequently detected in diabetics (OR = 17.37 and 13.00, respectively). CAC score was significantly greater in males. CAC and AAC scores were correlated significantly with pack-years of smoking and plasma osteoprotegrin levels. However the independent contribution of plasma osteoprotegerin levels was not confirmed in multiple regression analysis. Age (OR = 1.13) and hemodialysis vintage (OR = 1.14) were the independent risk factor favoring the occurrence of CAC; while age (OR = 1.20) was the only predictor of AAC occurrence in HD.Conclusions1. AAC precedes the occurrence of CAC in HD patients. 2. The exposition to uremic milieu and systemic chronic microinflammation has more deteriorative effect on the CAC than the AAC.

Renal artery stenosis (RAS) is an important cause of arterial hypertension and chronic kidney disease. The aims of our study were to assess the prevalence of RAS and to examine the frequency of variants of renal vasculature, that is, multiple and/or accessory renal arteries in hypertensive patients referred to renal angiography. We evaluated retrospectively 1554 arteriographies of hypertensive patients. Angiograms were evaluated to find RAS, significant RAS (460% stenosis of the lumen), radiological signs of atherosclerosis, aneurysms of the renal arteries or aorta and variants of kidney vascularization. The frequency of RAS including occlusions was 15.1% (21.3% of them were significant and suitable for revascularization). Variants of renal arterial vascularization were found in 26.5% of patients (multiple renal arteries-11.2% and accessory renal arteries-15.3%). Significant RAS was found more frequently in patients older than 60 years-OR 4.76 (2.08-10.86). Coronary artery disease, history of myocardial infarction or stroke significantly increased the chance of RAS detection. The frequency of renal accessory arteries was lower in patients older than 60 years and in patients with the radiological signs of atherosclerosis. Results of this study indicate that haemodynamically important RAS is found more frequently in hypertensive patients older than 60 years. Symptomatic atherosclerotic disease found in the peripheral and/or coronary arteries and diabetes mellitus increases the chance of RAS detection. Decreased occurrence of renal accessory arteries was found in hypertensive patients with radiological signs of atherosclerosis.

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Diffusion tensor imaging is unique in its ability to non-invasively visualize white matter fiber tracts in the human brain in vivo. White matter fiber bundles of the human brain form a spatial defined by the anatomical and functional architecture. Determination of axonal pathways provides an invaluable means to study the connectivity of human brain and its functional network. Comparison of fiber tract properties across subjects requires comparison at corresponding anatomical locations. In this paper, we present application of white matter tractography method based on incoherent motion of water molecules in fiber tissue, mainly in central nervous system. This motion is itself dependent on the micro-structural environment that restricts the movement of the water molecules. In white matter fibers there is a pronounced directional dependence on diffusion. With white matter fiber tracking or tractography, projections among brain regions can be detected in the three-dimentional diffusion tensor dataset according to the directionality of the fibers. The authors indicate diagnostic possibilities of MR tractography in otolaryngology for imaging the nervous tracts of sense of hearing, smell and taste with particular consideration of otoneurological evaluation of patients with cochlear implants and bone anchored hearing aid (BAHA). White matter tracts can be evaluated independently by using diffusion tensor tractography, which appears to be a promising technique for determining changes in white matter in degenerative disease. The authors also indicate that method as a beneficial in the surgical planning for patients with intrinsic brain tumors.

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