Degree Of Wall Thickening Research Articles

Temporal artery compression sonography for the diagnosis of giant cell arteritis in elderly patients with acute ocular arterial occlusions.

To validate cut-off values of quantitative high-resolution temporal artery compression sonography (TCS) for the diagnosis of cranial GCA (cGCA) in patients with acute arterial ocular occlusions and in an independent control group. Consecutive patients who underwent TCS as part of the diagnostic workup of acute arterial ocular occlusions and controls not suffering from ocular ischaemia/systemic vasculitis were included. The diagnostic accuracy of the established TCS cut-off value of maximum temporal artery wall thickness (≥0.7 mm) and a novel numeric TCS score incorporating the degree of wall thickening in the four temporal artery segments assessed (0-3 points per segment) was tested by receiver operating characteristics analysis. Subgroup analyses were performed for female and male patients and patients older and younger than age of 70 years. Of 114 patients with acute ocular arterial occlusions, 30 patients received a final clinical diagnosis of cGCA. The sensitivity and specificity of the ≥0.7 mm TCS cut-off for the diagnosis of cGCA were 100 and 84.5% in the overall cohort. The TCS score did not improve the diagnostic yield (cut-off ≥5; sensitivity 100%, specificity 85.7%). In male patients >70 years of age, the specificity of TCS was limited, secondary to age- and sex-related differences in temporal artery wall thickness, which we confirmed in the independent control group. TCS yields high diagnostic accuracy in the diagnosis of cGCA in patients with acute ocular arterial occlusions. Age- and sex-related differences in temporal artery wall thickness influence the diagnostic accuracy of TCS.

Abstract TP130: The Clinical Value of Magnetic Resonance Vessel Wall Maging in Patients With Central Nervous System Vasculitis

Background and Purpose: Prompt and accurate diagnosis of central nervous system (CNS) vasculitis is essential for treatment decision making and prevention of irreversible brain damage. However, diagnosis is often challenging even with digital subtraction angiography and biopsy. The purpose of this study was to investigate the value of magnetic resonance vessel wall imaging (MR-VWI) in diagnosis and management of CNS vasculitis. Methods: We retrospectively reviewed 13 patients with clinically defined CNS vasculitis who underwent intracranial MR-VWI. Two patients had imaging follow-up after treatment. The imaging protocol included conventional T1/T2 brain MR, diffusion-weighted imaging, MRA, and pre- and post-contrast T1-weighted whole-brain MR-VWI. An experienced neuroradiologist reviewed MR-VWI images to characterize vessel wall characteristics (lumen narrowing, pattern of wall thickening, and grade of contrast enhancement) at major intracranial arterial segments. Additionally, the changes in the brain parenchyma and meninges were evaluated. Results: Of these 13 patients (6 men, age 28-70 years), 4 had acute infarction. Six patients had intracranial artery stenosis on MRA, but 11 patients showed vessel wall abnormality on MR-VWI. Eleven patients showed multiple, smooth, wall thickening and pronounced contrast enhancement, which were concentric in 9 and eccentric in 2. Two of these 11 patients had follow-up imaging after treatment; imaging findings remained stable in one and the degree of wall thickening and enhancement reduced in the other. In 2 of 13 patients, meningeal enhancement was observed in the absence of vascular wall thickening. Conclusions: MR-VWI depicts CNS vasculitis with characteristic multiple, smooth, vessel wall thickening and contrast enhancement, with most of cases being of concentric pattern. These features may provide useful information for early and accurate diagnosis as well as for tracking treatment response.

FE simulation study of deep drawing process of SUS304 cups having no delayed cracks under enhanced blank holding force

In the experiment, delayed cracks in deep drawing processes of metastable stainless steel SUS304 cylindrical cups were prevented using elevated blank holding force aided by nanolubrication. Besides tensile residual hoop stresses, the elimination of the cracks was also attributed to the change in wall thickening profile along the wavy cup edges. The wall thickening is a result of the high circumferential stress acting in the flange, leading to the high concentration of deformation-induced martensite and high risk of cracks. The amount of increase in wall thickness in the valleys along the edge during the deep drawing process was higher than the peaks at low blank holding force range due to shorter heights. Therefore, the portions of blank equivalent to the valleys were subject to higher holding force during the process, resulting in decrease in degree of wall thickening with increase in height for blank holding force up to 25 kN. However, the wall thickening and the height increased at blank holding force of 28 kN due to the same amount of increase in wall thickness in both valleys and peaks, resulting in a larger contacting area and lower holding force. Therefore, the wall thickness in the valleys sharply increased, and the formation of the cracks persists. Within the crack-free range, that is, from 29 to 31 kN, both the heights and wall thickening decreased. The decrease in frictional force by means of the nanolubrication has facilitated the flow of material into the die, resulting in lower cup height. It also facilitated the flow of materials away from the thick valley regions under the high pressure, resulting in significant decrease in degree of wall thickening. The cracks were prevented. The amount of compression at blank holding force of 32 kN was insufficient to suppress the increase in wall thickening in valleys, resulting in the formation of the cracks again.

Effect of additional axial tension on formability of equal curvature-diameter bending without mandrel for 0Cr18Ni9 stainless steel tube

The equal curvature-diameter (ECD; R0/D0 = 1.0; where R0 is the bending radius, and D0 is the outer diameter of tube) bending process without mandrel was regarded as the tube’s minimal bending condition. Compared with pure bending, this represented a very complex physical process with multifactor effects. The quality and forming limit of tube bending are affected by additional axial tension (AAT); therefore, in this study, the ECD bending process without mandrel for tubes was performed by combining the finite element (FE) method and experimental research. The effects of AAT on the bending formability, such as wall thickness variation, cross-section distortion, and springback, were investigated. The results showed that: (1) under a certain friction coefficient between the tube and pressure die, AAT was constant, the maximum wall thickness variation rate, the maximum cross-section minor axis variation rate, and the springback angle all increased with the increase of the bending angle; (2) under a certain bending angle, maximum wall thinning rate, maximum cross-section short axis variation rate, and springback angle were positively associated with the friction coefficient, while the wall thickening rate was negatively associated with it. These data implied that the maximum wall thinning rate, the maximum cross-section short axis variation rate, and the springback angle all increased, while the maximum wall thickening rate decreased with the increase of AAT; (3) when the friction coefficient was too small, AAT was too small. Although the degree of the wall thinning, cross-section distortion, and springback were relatively small, the degree of wall thickening was large and even wrinkled. On the contrary, when the friction coefficient was too large, AAT was too large. Although the degree of maximum wall thickening was relatively small, the degree of maximum wall thinning, maximum cross-section short axis variation rate, and the springback angle were large, and the tube’s surface was extensively scratched. When the friction coefficient was too large, it would have a negative impact on the comprehensive bending formability of tube. In conclusion, our study indicates that in order to ensure a tube’s comprehensive bending formability, AAT should be properly controlled by reducing the friction coefficient between the tube and pressure die.

The surprising anatomical diversity in the roots of African Restionaceae

The root anatomy of 291 of the 350 species of the African Restionaceae, one of the ecologically dominant and taxonomically diverse elements of the Cape flora, is reported. There is substantial variation in the cortex (either collapses in older roots or persists as an aerenchyma), endodermis (in relative size, shape of the endodermal cells, and degree of wall thickening), pericycle (from 1 to 10 cells, varying from unthickened to massively thickened), and the metaxylem vessels (5 to more than 100, organized in a ring or scattered). Almost all root anatomical characters are phylogenetically constrained, similar to the culm anatomical characters. Although it is possible to, based on root anatomy, recognize groups of genera with broadly similar root anatomies, there are often also exceptions, indicating some evolutionary lability. Variation not phylogenetically controlled is significantly explained by differences in ground water availability and mean annual precipitation. The descriptive data are available in an online interactive key. The variation in root anatomy may contribute interesting insight into the evolution of this unusual group of plants.

Histopathological Differences Between the Anterior and Posterior Brain Arteries as a Function of Aging.

We tested the hypothesis that posterior brain arteries differ pathologically from anterior brain arteries and that this difference varies with age. Brain large arteries from 194 autopsied individuals (mean age 56±17 years, 63% men, 25% nonwhite, 17% with brain infarcts) were analyzed to obtain the areas of arterial layers and lumen as well as the relative content of elastin, collagen, and amyloid. Visual rating was used to determine the prevalence of atheroma, calcification, vasa vasorum, pattern of intima thickening, and internal elastic lamina gaps. We used multilevel models adjusting for age, sex, ethnicity, vascular risk factors, artery type and location, and multiple comparisons. Of 1362 large artery segments, 5% had vasa vasorum, 5% had calcifications, 15% had concentric intimal thickening, and 11% had atheromas. Posterior brain arteries had thinner walls, less elastin, and more concentric intima thickening than anterior brain arteries. Compared to anterior brain arteries, the basilar artery had higher arterial area encircled by the internal elastic lamina, whereas the vertebral arteries had higher prevalence of elastin loss, concentric intima thickening, and nonatherosclerotic stenosis. In younger individuals, vertebral artery calcifications were more likely than calcification in anterior brain arteries, but this difference attenuated with age. Posterior brain arteries differ pathologically from anterior brain arteries in the degree of wall thickening, elastin loss, and concentric intimal thickening.

Left Ventricular Structure and Function in Transthyretin-Related Versus Light-Chain Cardiac Amyloidosis

Immunoglobulin amyloid light-chain (AL)-related cardiac amyloidosis (CA) has a worse prognosis than either wild-type (ATTRwt) or mutant (ATTRm) transthyretin (TTR) CA. Detailed echocardiographic studies have been performed in AL amyloidosis but not in TTR amyloidosis and might give insight into this difference. We assessed cardiac structure and function and outcome in a large population of patients with CA and compared findings in TTR and AL-related disease. We analyzed 172 patients with CA (AL amyloidosis, n=80; ATTRm, n=36; ATTRwt, n=56) by standard echocardiography and 2-dimensional speckle-tracking imaging-derived left ventricular (LV) longitudinal (LS), radial, and circumferential strains. Despite a preserved LV ejection fraction (55±12%), LS was severely impaired in CA. Standard measures of LV function and speckle-tracking imaging worsened as wall thickness increased, whereas apical LS was preserved regardless of the pathogenesis of CA and the degree of wall thickening. Compared with ATTRm and AL amyloidosis, ATTRwt was characterized by greater LV wall thickness and lower ejection fraction. LS was more depressed in both ATTRwt and AL amyloidosis (-11±3% and -12±4%, respectively, P=0.54) than in ATTRm (-15±4%, P<0.01 versus AL amyloidosis and ATTRwt). TTR-related causes were favorable predictors of survival, whereas LS and advanced New York Heart Association class were negative predictors. In patients with CA, worsening LV function correlated with increasing wall thickness regardless of pathogenesis. Patients with ATTRwt had a statistically greater wall thickness but lesser mortality than those with AL amyloidosis, despite very similar degrees of LS impairment. This paradox suggests an additional mechanism for LV dysfunction in AL amyloidosis, such as previously demonstrated light-chain toxicity.

Ultrasound findings in urinary shistosomaisis infection in school children in the Gezira state central Sudan

To evaluate the ultrasound findings of urinary schistosomiasis in Quran school (Khalwas) children in Gezira State Sudan, we studied all the students from two schools. A total of 103 boys were tested for urinary schistosomiasis using the urine filtration method. Schistosoma haematobium (S. haematobium) eggs were counted. Ultrasound was performed for all the positive subjects. Seventy-three (71%) subjects were positive for S. haematobium. The mean age was 11.3 ± 2.9 years. Sixty-six (90.4%) subjects showed urinary tract abnormalities. The findings revealed the following degrees of wall thickening: 53.0% mild, 18.2% moderate and 21.2% severe. Urinary bladder polyp(s) were noted in 43.3% (single) and 40.9% (multiple) of the subjects, and calcification of the bladder wall was observed in 7.6% subjects. Ureteric dilatation was noted in 38/73 (52.0%), while hydronephrosis was detected in 19/73 (26.3%). The vast majority of urinary tract schistomiasis lesions were in the urinary bladder. Ultrasound is a useful tool for identifying the morbidity of S. haematobium in endemic areas.

Multidetector row computed tomography findings from ischemia to infarction of the large bowel

Objective MDCT is performed as first imaging examination for patients with acute abdomen in most Emergency Departments. Clinical suspicion of ischemic colitis and infarction is related to specific findings, however, differential diagnosis as well as the staging for a confirmed ischemic affection may be critical. The individual signs from ischemia to infarction of large bowel is a captivating topic. In this study, we report our experience of the MDCT assessment of acute colonic disease from vascular mesenteric disorders. Materials and methods We retrospectively reviewed the MDCT findings of 71 patients admitted to our attention for acute abdomen, with final proven diagnosis of colonic ischemia and/or infarction made by surgery and/or endoscopy. CT-scanning of the abdomen and pelvis was performed after i.v. contrast medium administration, using a multidetector row CT equipment. We correlated the presence of parietal disease, the evidence of mesenteric arterial or venous vessels occlusion, the parietal features as well as others findings, such as free fluid and/or air in peritoneal recess or in retroperitoneum, with the surgical and/or endoscopic findings. Results Analysis of our data showed a segmental (84%) or complete (16%) involvement of the colon; 57 cases were related to ischemia, 14 to infarction. Inferior mesenteric vessels defect of opacification was noted in 10 cases. Various degree of wall thickening and parietal enhancement, peritoneal fluid, mural or portal-mesenteric pneumatosis were compared to evidence of mesenteric arterial or vein occlusion and to final proven diagnosis. A classification in a multi-stage grading for both decreased of arterial supply or impaired venous drainage disorders was done. Conclusions A grading scale from ischemia to infarction affecting the large bowel from arterial or venous mesenteric vessels origin has been not previously reported in a series at our knowledge. MDCT findings may support the clinical evaluation of patients affected by acute colon from vascular disorders. In particular, it seems to provide effective and valuable information's in differentiating etiology and stage of disease.

Left ventricular hypertrophy. Relation of structure to diastolic function in hypertension.

Digitised M mode echocardiography was used to determine the relation between the degree of left ventricular hypertrophy and abnormalities of isovolumic relaxation and diastolic function. Fifty six patients with varying severity of non-malignant systemic hypertension without evidence of ischaemic heart disease, left ventricular dilation, or clinical heart failure were studied. In addition, 10 athletes with hypertrophy and 20 normal subjects were studied. Athletes and patients with moderate (systolic blood pressure 175 to 200 mm Hg) and severe hypertension (greater than 200 mm Hg) had a significant increase in left ventricular mass. Cavity dimensions were normal in hypertensive patients and increased in athletes. Systolic function was normal in all groups. Regardless of the degree of hypertrophy patients with hypertension had a prolonged isovolumic relaxation period and delayed mitral valve opening. Patients with hypertrophy also had a reduced rate and prolonged duration of rapid early diastolic dimension increase and posterior wall thinning. Athletes, however, who had an equivalent degree of hypertrophy to patients with moderate or severe hypertension had entirely normal function. Measurements of diastolic function were significantly correlated with wall thickness and left ventricular mass. These indices of hypertrophy, particularly posterior wall thickness and the sum of posterior wall and septal thickness, were positively correlated with the duration of isovolumic relaxation and delay in mitral opening and negatively with the peak rate of early diastolic dimension increase and wall thinning. Thus in hypertensive patients with non-dilated left ventricular hypertrophy there appears to be a relation between the degree of wall thickening and abnormalities of diastolic function.

The structure of barley roots in relation to the transport of ions into the stele

Three successive states are recognized in the development of endodermal cells in seminal and nodal axes and primary lateral roots of barley: 1. Casparian bands in the anticlinal walls; 2. suberin lamella around the whole inner face of the wall; 3. unevenly deposited cellulosic wall thickening. These states develop asynchronously, the cells adjacent to the protoxylem pole cells always being last to mature. All cells have progressed to at least the secondary state by 32 cm from the tip in seminal axes, 48 cm from the tip in nodal axes, but only 6 cm from the tip in primary laterals. The asynchronous development gives the appearance of “passage” cells adjacent to the protoxylem pole cells, although all cells eventually attain the same state and degree of wall thickening. Long distance transport of calcium shows a close correlation with the incidence of suberin lamellae in the three types of root examined; it is suggested that formation of a suberin lamella effectively blocks calcium movement into the stele and, therefore, long distance transport. Plasmodesmata are present in comparable frequencies through both tangential and radial endodermal walls; they appear to maintain intercellular continuity until a late stage in development.