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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Wook Yi ◽  
Keunyoung Kim ◽  
Myungsoo Im ◽  
Soree Ryang ◽  
Eun Heui Kim ◽  
...  

AbstractWe evaluated the associations between metabolic parameters with visceral adipose tissue (VAT) volume in women with prediabetes or type 2 diabetes (T2DM), and we compared the VAT volume with the VAT area. We enrolled women aged > 20 years with prediabetes or T2DM, who underwent oral glucose tolerance test and whose VAT was evaluated using computed tomography (CT) at our institution between 2017 and 2019. All participants underwent unenhanced spiral CT with a 3-mm slice thickness from the level of the diaphragm to the level of the mid-thigh. The two VAT areas were defined as the free drawn area on the levels of the umbilicus and L2 vertebra. The VAT areas were also manually drawn from the level of the diaphragm to the level of the pelvic floor and were used to calculate the VAT volumes by summing all areas with a slice thickness of 3 mm after setting the attenuation values from −45 to −195 Hounsfield Unit. All metabolic characteristics, except blood pressure, were significantly correlated with the VAT volume. The VAT areas measured at the level of the L2 vertebra and umbilicus were correlated with serum triglyceride, high-density lipoprotein cholesterol, and Framingham steatosis index alone. Multivariable regression analyses revealed that the VAT volume was significantly associated with several metabolic parameters. In conclusion, in women with prediabetes and T2DM, the VAT volume acquired from CT-based calculation has more significant correlations with metabolic risk factors compared with the VAT area.


Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 114
Author(s):  
Antai Chang ◽  
Xia Zheng ◽  
Hongwei Xiao ◽  
Xuedong Yao ◽  
Decheng Liu ◽  
...  

The main objective of the present work was to study the drying kinetics and obtain the optimum process parameters of cantaloupe slices using short-and medium-wave infrared radiation (SMIR) drying technology. The effect of three independent variables of infrared radiation temperature (55–65 °C), slice thickness (5–9 mm) and radiation distance (80–160 mm) on the L value, color difference (∆E), hardness and vitamin C content were investigated by using the Response Surface Methodology (RSM). The results showed that the Page model can adequately predict the moisture content between 55 and 65 °C (R2 > 0.99). The effective moisture diffusivity (Deff) varied from 5.26 × 10−10 to 2.09 × 10−9 m2/s and the activation energy (Ea) of the SMIR drying was 31.84 kJ/mol. Infrared radiation temperature and slice thickness exerted extremely significant effects on L value and color difference (ΔE) (p < 0.01), with higher infrared radiation temperature and thin slice thickness leading to a decrease in the L value and an increase in ΔE. Hardness and vitamin C content were significantly affected by infrared radiation temperature, slice thickness and radiation distance, of which the slice thickness was the most distinct factor affecting the hardness value. Higher infrared radiation temperature and larger slice thickness and radiation distance resulted in higher vitamin C degradation. For the given constraints (maximized vitamin C content and L value, minimized ΔE and hardness value), the optimum drying parameters were infrared radiation temperature 58.2 °C, slice thickness 6 mm and radiation distance 90 mm. Under the optimum drying combination conditions, the experimental values were 65.58 (L value), 8.57 (∆E), 10.49 N (hardness) and 106.58 mg/100 g (vitamin C content), respectively. This study is beneficial to the development of the cantaloupe food processing industry and provides more insights for the application of SMIR drying technology to improve the drying rate and product quality of cantaloupe.


2022 ◽  
Vol 52 (1) ◽  
pp. 43-48
Author(s):  
Ibrahim Doymaz

The effect of different infrared (IR) powers on drying of orange slices was investigated in infrared dryer. The orange slices dried at 62, 74 and 88 W infrared powers and constant slice thickness of 6 mm. Results showed that drying, colour and rehydration characteristics of orange slices were greatly influenced by infrared power. The drying data were fitted with five mathematical models available in the literature. Based on the statistical tests applied to make an assessment, the model of Midilli and Kucuk was found to satisfactorily explain drying kinetics of orange slices for all drying conditions. The Fick’s diffusion model was used to calculate the effective moisture diffusivity (Deff) of orange slices. The value of Deff varied from 1.59×10-10 to 2.49×10-10 m2/s. It was found that the effective moisture diffusivities increased with increasing IR power. Activation energy was estimated by a modified Arrhenius type equation as 2.11 kW/kg. As the infrared power increased, the rehydration ratio was found to be reduced. Furthermore, with increase of infrared power, the values of a and DE increased, whereas the values of L, b and C decreased.


2021 ◽  
Vol 12 ◽  
Author(s):  
A Ram Hong ◽  
Miwoo Lee ◽  
Jung Hyun Lee ◽  
Jung Hee Kim ◽  
Yong Hwy Kim ◽  
...  

ObjectiveSeveral attempts have been done to capture damaged hypothalamus (HT) using volumetric measurements to predict the development of hypothalamic obesity in patients with craniopharyngioma (CP). This study was to develop a novel method of HT volume measurement and examine the associations between postoperative HT volume and clinical parameters in patients with CP.MethodsWe included 78 patients with adult-onset CP who underwent surgical resection. Postoperative HT volume was measured using T1- and T2-weighted magnetic resonance imaging (MRI) with a slice thickness of 3 mm, and corrected for temporal lobe volume. We collected data on pre- and postoperative body weights, which were measured at the time of HT volume measurements.ResultsThe corrected postoperative HT volume measured using T1- and T2-weighted images was significantly correlated (r=0.51 [95% confidence interval (CI) 0.32 to 0.67], P&lt;0.01). However, HT volume was overestimated using T1-weighted images owing to obscured MR signal of the thalamus in patients with severe HT damage. Therefore, we used T2-weighted images to evaluate its clinical implications in 72 patients with available medical data. Postoperative HT volume was negatively associated with preoperative body weight and preoperative tumor volume (r=–0.25 [95% CI -0.45 to -0.04], P=0.04 and r=–0.26 [95% CI -0.40 to -0.15], P=0.03, respectively). In the subgroup analysis of CP patients who underwent primary surgery (n=56), pre- and postoperative body weights were negatively associated with HT volume (r=–0.30 [95% CI -0.53 to -0.03], P=0.03 and r=–0.29 [95% CI -0.53 to -0.02], P=0.03, respectively).ConclusionsAdult-onset CP patients showed negative associations between postoperative HT volume and preoperative/postoperative body weight using a new method of HT volume measurement based on T2-weighted images.


BMC Surgery ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yoshihito Iijima ◽  
Masahito Ishikawa ◽  
Shun Iwai ◽  
Aika Yamagata ◽  
Nozomu Motono ◽  
...  

Abstract Background Congenital pericardial defects are rare congenital anomalies, often asymptomatic and incidentally detected during thoracic surgery. Case presentation A 74-year-old man with primary lung cancer (cT1cN0M0, Stage IA3) underwent thoracoscopic radical lobectomy. At the time of thoracotomy, a pericardial defect was found on the ventral side of the hilar region, and the left atrial appendage was exposed. Due to concern that contact between the bronchial stump and the left atrial appendage may lead to postoperative bleeding and heart hernia, the pericardial defect was closed with an expanded polytetrafluoroethylene GoreTex® membrane. Preoperative computed tomography was reanalyzed with a 1 mm slice, congenital pericardial defect was detected as the pericardium had penetrated under the left atrial appendage. Conclusions In congenital partial pericardial defect, contact between the left atrial appendage and bronchial stump, due to movement of the lung or heart, increases the risk of bleeding after lung resection. Therefore, closure of the defect should be considered. Although it is difficult to diagnose congenital partial pericardial defect preoperatively, computed tomography taken with a slice thickness of 1 mm is useful for diagnosis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vanessa Franziska Schmidt ◽  
Federica Arnone ◽  
Olaf Dietrich ◽  
Max Seidensticker ◽  
Marco Armbruster ◽  
...  

AbstractNeedle artifacts pose a major limitation for MRI-guided interventions, as they impact the visually perceived needle size and needle-to-target-distance. The objective of this agar liver phantom study was to establish an experimental basis to understand and reduce needle artifact formation during MRI-guided abdominal interventions. Using a vendor-specific prototype fluoroscopic T1-weighted gradient echo sequence with real-time multiplanar acquisition at 1.5 T, the influence of 6 parameters (flip angle, bandwidth, matrix, slice thickness, read-out direction, intervention angle relative to B0) on artifact formation of 4 different coaxial MR-compatible coaxial needles (Nitinol, 16G–22G) was investigated. As one parameter was modified, the others remained constant. For each individual parameter variation, 2 independent and blinded readers rated artifact diameters at 2 predefined positions (15 mm distance from the perceived needle tip and at 50% of the needle length). Differences between the experimental subgroups were assessed by Bonferroni-corrected non-parametric tests. Correlations between continuous variables were expressed by the Bravais–Pearson coefficient and interrater reliability was quantified using the intraclass classification coefficient. Needle artifact size increased gradually with increasing flip angles (p = 0.002) as well as increasing intervention angles (p < 0.001). Artifact diameters differed significantly between the chosen matrix sizes (p = 0.002) while modifying bandwidth, readout direction, and slice thickness showed no significant differences. Interrater reliability was high (intraclass correlation coefficient 0.776–0.910). To minimize needle artifacts in MRI-guided abdominal interventions while maintaining optimal visibility of the coaxial needle, we suggest medium-range flip angles and low intervention angles relative to B0.


2021 ◽  
pp. 1-10
Author(s):  
Gyeong Rip Kim ◽  
ung Ho Kim ◽  
Soon Ki Sung ◽  
Chang Hyeun Kim ◽  
Sang Bong Lee ◽  
...  

OBJECTIVE: To invastgate feasibility of low-dose contrast agent in cerebral computed tomography angiography (CTA) to alleviate side effects. METHOD: Siemens’ Somatom Definition AS+CT scanner, Heine’s blood pressure monitor G7-M237 (BP cuff) and Ultravist contrast agent (370 mg Iodine/ml) are used. CTA is acquired using following scan parameters including slice thickness of 1mm, image acquisition parameters of 128×0.6 mm, pitch size of 0.8 mm, 175 effective mAs, 120 kVp tube voltage, scan delay time of 3 seconds, and the scan time of 4 seconds. This study is conducted by securing the IV route in the left antecubital vein before injection of contrast agent, wrapping BP cuff around the branchial artery of the opposite right arm after setting the pressure to 200 mmHg. Then, the injection rate of the contrast agent is fixed at 4.5 cc/sec and contrast agent was injected in three different amounts (70, 80, and 100 cc). Bp cuff is released from this moment when HU value reachs 100. RESULT: In this study, the mean HU values measured from common carotid artery are 412.45±5.89 when injecting 80cc contrast agent and using BP cuff and 399.64±5.51 when injecting 100 cc contrast agenet and not using BP cuff, respectively. In middle cerebral artery M1, the mean HU values are 325.23±38.29 when injecting 80cc contrast agent and using BP cuff and 325.00±30.63 when injecting 100cc contrast agent blood and not using pressure cuff, respectively. Difference of mean HU values is not statistically significant (p >  0.05) with and without using BP cuff. CONCLUSION: This study demonstrates that reducing amount of contrast agent is possible when the right brachial artery is compressed using BP cuff. Study results indicate that reducing 20% injection of contrast agent in CT cerebrovascular angiography can still yield comparable imaging results with conventional contrast angent usage, which implies that less side effects are expected with a contrast agent injection. Thus, this study can serve as a reference for potential reducing side effect during CT cerebrovascular angiography.


2021 ◽  
Vol 2 ◽  
pp. 90-96
Author(s):  
Asep Yusuf ◽  
Lambok Sinaga ◽  
Wahyu K. Sugandi

Canna (Canna edulis Kerr.) is a type of tuber plant with a fairly high starch content to be used as food. The use of canna is generally processed first into flour. The initial process of flouring canna is done in two ways; the canna plants are sliced and grated. The Department of Agricultural and Biosystem Engineering, Faculty of Agricultural Industrial Technology, University of Padjadjaran, designed the TEP-1902 Canna Slicing and Shredding Machine (MPPG). However, the performance of this machine was not yet known, so testing was needed to determine its performance. The research method used was an experimental method that was analyzed descriptively by measuring, observing, calculating, analyzing, testing, and evaluating the TEP-1902 Canna Slicing and Shredding Machine (MPPG). The results of the performance test of this machine showed that the machine's performance was good, with the following parameters: the actual capacity of the slicing unit and grating unit was 40.95 kg/hour and 182.98 kg/hour, respectively, efficiency was 92.61% slicing and 97.60% grater, the yields were 98.75% slicing and 96.50% grating, respectively, the average thickness of the slices was 2.13 mm, and the uniformity of slice thickness was 65.51%.


2021 ◽  
pp. 41-44
Author(s):  
Kataria Bhavya ◽  
Mehra Shibani

AIMS AND OBJECTIVES: To correlate the Diffusion MRI assessed infarct volume with the ASPECT Score to prognosticate clinical outcome in patients of acute stroke. METHOD AND MATERIALS: This was a cross sectional study comprising 36 patients of acute stroke. Diffusion weighted MR was obtained at b values of 0,500 & 1000 on Siemens Magnetom Skyra 3 Tesla scanner. Diffusion restriction on b=1000 image was measured with VOI tool using manual contouring in each slice. Volume was calculated using the formula (Area x slice thickness) after summating the infarct area measured in each slice. ASPECT Score was assessed on CT in each patient at the time of admission of the patient. Correlation of the infarct volume with ASPECTS was done using student t-test with p < 0.05 considered statistically signicant. ROC curve was used to predict cut off of volume of infarct & ASPECTS predicting adverse patient outcome. RESULTS: There was a statistically signicant inverse correlation between the volume of infarct and ASPECTS (p=0.001; r=-0.844). The AUC for a cut-off of 115 cc of the volume of infarct in predicting adverse patient outcome was 0.931 whereas that for ASPECT Scale of 6 was 0.931. CONCLUSION: Infarct volume correlates well with ASPECT Score, both serving as prognostic tools in predicting patient outcome in acute stroke and having comparable efcacy in predicting prognosis. BACKGROUND: Infarct volume and CT ASPECT Score are resourceful parameters in predicting patient prognosis. Limited studies have been done in the Indian population correlating the Volume of infarct and the CT ASPECT Scale.


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