4. Median/ulnar nerve ultrasound cross-sectional area ratio in ALS

Abstract Background While supraspinatus atrophy can be described according to the system of Zanetti or Thomazeau there is still a lack of characterization of isolated subscapularis muscle atrophy. The aim of this study was to describe patterns of muscle atrophy following repair of isolated subscapularis (SSC) tendon. Methods Forty-nine control shoulder MRI scans, without rotator cuff pathology, atrophy or fatty infiltration, were prospectively evaluated and subscapularis diameters as well as cross sectional areas (complete and upper half) were assessed in a standardized oblique sagittal plane. Calculation of the ratio between the upper half of the cross sectional area (CSA) and the total CSA was performed. Eleven MRI scans of patients with subscapularis atrophy following isolated subscapularis tendon tears were analysed and cross sectional area ratio (upper half /total) determined. To guarantee reliable measurement of the CSA and its ratio, bony landmarks were also defined. All parameters were statistically compared for inter-rater reliability, reproducibility and capacity to quantify subscapularis atrophy. Results The mean age in the control group was 49.7 years (± 15.0). The mean cross sectional area (CSA) was 2367.0 mm2 (± 741.4) for the complete subscapularis muscle and 1048.2 mm2 (± 313.3) for the upper half, giving a mean ratio of 0.446 (± 0.046). In the subscapularis repair group the mean age was 56.7 years (± 9.3). With a mean cross sectional area of 1554.7 mm2 (± 419.9) for the complete and of 422.9 mm2 (± 173.6) for the upper half of the subscapularis muscle, giving a mean CSA ratio of 0.269 (± 0.065) which was seen to be significantly lower than that of the control group (p < 0.05). Conclusion Analysis of typical atrophy patterns of the subscapularis muscle demonstrates that the CSA ratio represents a reliable and reproducible assessment tool in quantifying subscapularis atrophy. We propose the classification of subscapularis atrophy as Stage I (mild atrophy) in case of reduction of the cross sectional area ratio < 0.4, Stage II (moderate atrophy) in case of < 0.35 and Stage III (severe atrophy) if < 0.3.

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Use of Cardiac Magnetic Resonance Imaging Based Measurements of Inferior Vena Cava Cross-Sectional Area in the Diagnosis of Pericardial Constriction

Canadian Association of Radiologists Journal ◽

10.1016/j.carj.2014.12.007 ◽

2015 ◽

Vol 66 (3) ◽

pp. 231-237 ◽

Cited By ~ 2

Author(s):

Kate Hanneman ◽

Paaladinesh Thavendiranathan ◽

Elsie T. Nguyen ◽

Hadas Moshonov ◽

Rachel Wald ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Cardiac Magnetic Resonance ◽

Inferior Vena ◽

Vena Cava ◽

Area Ratio ◽

Cross Sectional Area ◽

Sectional Area ◽

Resonance Imaging ◽

Cross Sectional ◽

Aortic Area

Purpose To evaluate the value of cardiac magnetic resonance imaging (MRI)–based measurements of inferior vena cava (IVC) cross-sectional area in the diagnosis of pericardial constriction. Methods Patients who had undergone cardiac MRI for evaluation of clinically suspected pericardial constriction were identified retrospectively. The diagnosis of pericardial constriction was established by clinical history, echocardiography, cardiac catheterization, intraoperative findings, and/or histopathology. Cross-sectional areas of the suprahepatic IVC and descending aorta were measured on a single axial steady-state free-precession (SSFP) image at the level of the esophageal hiatus in end-systole. Logistic regression and receiver-operating curve (ROC) analyses were performed. Results Thirty-six patients were included; 50% (n = 18) had pericardial constriction. Mean age was 53.9 ± 15.3 years, and 72% (n = 26) were male. IVC area, ratio of IVC to aortic area, pericardial thickness, and presence of respirophasic septal shift were all significantly different between patients with constriction and those without ( P < .001 for all). IVC to aortic area ratio had the highest odds ratio for the prediction of constriction (1070, 95% confidence interval [8.0-143051], P = .005). ROC analysis illustrated that IVC to aortic area ratio discriminated between those with and without constriction with an area under the curve of 0.96 (95% confidence interval [0.91-1.00]). Conclusions In patients referred for cardiac MRI assessment of suspected pericardial constriction, measurement of suprahepatic IVC cross-sectional area may be useful in confirming the diagnosis of constriction when used in combination with other imaging findings, including pericardial thickness and respirophasic septal shift.

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Assessment of sand stabilization potential of a plant-derived biomass

Science and Engineering of Composite Materials ◽

10.1515/secm-2014-0061 ◽

2016 ◽

Vol 23 (2) ◽

pp. 227-236 ◽

Cited By ~ 3

Author(s):

Dunja Perić ◽

Paul A. Bartley ◽

Lawrence Davis ◽

Ali Ulvi Uzer ◽

Cahit Gürer

Keyword(s):

Area Ratio ◽

Cross Sectional Area ◽

Experimental Program ◽

Early Age ◽

Shear Stresses ◽

Sectional Area ◽

Cross Sectional ◽

Near Surface ◽

Total Cross Sectional Area ◽

Dry Sand

AbstractLignin is a coproduct of biofuel and paper industries, which exhibits binding qualities when mixed with water. Lignin is an ideal candidate for a sustainable stabilization of unpaved roads. To this end, an experimental program was devised and carried out to quantify effects of lignin on compaction and early age shear strength behaviors of sand. Samples were prepared by mixing a particular type of coproduct called calcium lignosulfonate (CaL) with sand and water. Based on the extensive analyses of six series of strength tests, it was found that a normalized cohesion increased with an increasing normalized areas ratio. Normalizations were carried out by dividing the cohesion and area ratio by gravimetric CaL content whereby the area ratio was obtained by dividing the portion of the cross-sectional area occupied with lignosulfonate-water (CaL-W) paste by the total cross-sectional area. While the increase in the normalized cohesion eventually leveled out, the cohesion peaked at 6% of CaL. Thus, sand-CaL-water (S-CaL-W) mixes sustained larger shear stresses than dry sand for a range of normal stresses below the limiting normal stress. Consequently, the early age behavior indicates that adding CaL-W to sand is clearly beneficial in the near-surface applications in dry sand.

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EXPERIMENTAL STUDY ON THE EFFECT OF CROSS-SECTIONAL AREA RATIO BETWEEN TUNNEL AND SHAFT ON PLUG-HOLING PHENOMENA IN SHALLOW UNDERGROUND TUNNELS

Computers in Railways XVI : Railway Engineering Design and Operation ◽

10.2495/cr180341 ◽

2018 ◽

Author(s):

KUN HYUK SUNG ◽

HONG SUN RYOU

Keyword(s):

Experimental Study ◽

Area Ratio ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional

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Role of diffusion tensor imaging in the evaluation of ulnar nerve involvement in leprosy

British Journal of Radiology ◽

10.1259/bjr.20210290 ◽

2021 ◽

pp. 20210290

Author(s):

Ankita Aggarwal ◽

Chandan Jyoti Das ◽

Neena Khanna ◽

Raju Sharma ◽

Deep Narayan Srivastava ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

Peripheral Neuropathy ◽

Ulnar Nerve ◽

Diffusion Tensor ◽

Cross Sectional Area ◽

Ulnar Neuropathy ◽

Control Group ◽

Sectional Area ◽

Cross Sectional

Objective: Early detection of peripheral neuropathy is extremely important as leprosy is one of the treatable causes of peripheral neuropathy. The study was undertaken to assess the role of diffusion tensor imaging (DTI) in ulnar neuropathy in leprosy patients. Methods: This was a case–control study including 38 patients (72 nerves) and 5 controls (10 nerves) done between January 2017 and June 2019. Skin biopsy proven cases of leprosy, having symptoms of ulnar neuropathy (proven on nerve conduction study) were included. MRI was performed on a 3 T MR system. Mean cross-sectional area, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of ulnar nerve at cubital tunnel were calculated. Additional ancillary findings and appearance of base sequences were evaluated. Results: Ulnar nerve showed thickening with altered T2W signal in all the affected nerves, having an average cross-sectional area of 0.26 cm2. Low FA with mean of 0.397 ± 0.19 and high ADC with mean of 1.28 ± 0.427 x 10 −3 mm2/s of ulnar nerve in retrocondylar groove was obtained. In the control group, mean cross-sectional area was 0.71cm2 with mean FA and ADC of 0.53 ± 0.088 and 1.03 ± 0.24 x 10 −3 mm2/s respectively. Statistically no significant difference was seen in diseased and control group. Cut-off to detect neuropathy for FA and ADC is 0.4835 and 1.1020 × 10 −3 mm2/s respectively. Conclusion: DTI though is challenging in peripheral nerves, however, is proving to be a powerful complementary tool for assessment of peripheral neuropathy. Our study validates its utility in infective neuropathies. Advances in knowledge: 1. DTI is a potential complementary tool for detection of peripheral neuropathies and can be incorporated in standard MR neurography protocol. 2. In leprosy-related ulnar neuropathy, altered signal intensity with thickening or abscess of the nerve is appreciated along with locoregional nodes and secondary denervation changes along with reduction of FA and rise in ADC value. 3. Best cut-offs obtained in our study for FA and ADC are 0.4835 and 1.1020 × 10 −3 mm2/s respectively.

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Numerical Investigation of a two-inlet PVT air collector

E3S Web of Conferences ◽

10.1051/e3sconf/201913605014 ◽

2019 ◽

Vol 136 ◽

pp. 05014

Author(s):

Zhangyang Kang ◽

Zhaoyang Lu ◽

Xin Deng ◽

Qiongqiong Yao

Keyword(s):

Heat Transfer ◽

Single Channel ◽

Numerical Study ◽

Convection Heat Transfer ◽

Thermal Characteristics ◽

Area Ratio ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional ◽

Maximum Heat

A numerical study of heat and mass transfer characteristics of a two-inlet PV/T air collector is performed. The influence of thermal characteristics and efficiency is investigated as the area ratios of inlet and outlet of the single channel with two inlets are changed. The design of the two-inlet PV/T air collector can avoid the poor heat transfer conditions of the single inlet PV/T air collector and improve the total photo-thermal efficiency. When the inlet/outlet cross-sectional area ratio is reduced, the inlet air from the second inlet enhances the convection heat transfer in the second duct and the temperature distribution is more uniform. As the cross-sectional area of the second inlet increase, the maximum heat exchange amount of the two-inlet PV/T air collector occurs between the inlet and outlet cross-sectional area ratio L=0.645 and L=0.562.

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