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1.
Journal of Southern Medical University ; (12): 724-732, 2022.
Article in Chinese | WPRIM | ID: wpr-936369

ABSTRACT

OBJECTIVE@#To propose a nonlocal spectral similarity-induced material decomposition network (NSSD-Net) to reduce the correlation noise in the low-dose spectral CT decomposed images.@*METHODS@#We first built a model-driven iterative decomposition model for dual-energy CT, optimized the objective function solving process using the iterative shrinking threshold algorithm (ISTA), and cast the ISTA decomposition model into the deep learning network. We then developed a novel cost function based on the nonlocal spectral similarity to constrain the training process. To validate the decomposition performance, we established a material decomposition dataset by real patient dual-energy CT data. The NSSD-Net was compared with two traditional model-driven material decomposition methods, one data-based material decomposition method and one data-model coupling-driven material decomposition supervised learning method.@*RESULTS@#The quantitative results showed that compared with the two traditional methods, the NSSD-Net method obtained the highest PNSR values (31.383 and 31.444) and SSIM values (0.970 and 0.963) and the lowest RMSE values (2.901 and 1.633). Compared with the datamodel coupling-driven supervised decomposition method, the NSSD-Net method obtained the highest SSIM values on water and bone decomposed results. The results of subjective image quality assessment by clinical experts showed that the NSSD-Net achieved the highest image quality assessment scores on water and bone basis material (8.625 and 8.250), showing significant differences from the other 4 decomposition methods (P < 0.001).@*CONCLUSION@#The proposed method can achieve high-precision material decomposition and avoid training data quality issues and model unexplainable issues.


Subject(s)
Humans , Algorithms , Image Processing, Computer-Assisted/methods , Phantoms, Imaging , Signal-To-Noise Ratio , Tomography, X-Ray Computed/methods , Water
2.
Journal of Southern Medical University ; (12): 849-859, 2022.
Article in Chinese | WPRIM | ID: wpr-941013

ABSTRACT

OBJECTIVE@#To build a helical CT projection data restoration model at random low-dose levels.@*METHODS@#We used a noise estimation module to achieve noise estimation and obtained a low-dose projection noise variance map, which was used to guide projection data recovery by the projection data restoration module. A filtering back-projection algorithm (FBP) was finally used to reconstruct the images. The 3D wavelet group residual dense network (3DWGRDN) was adopted to build the network architecture of the noise estimation and projection data restoration module using asymmetric loss and total variational regularization. For validation of the model, 1/10 and 1/15 of normal dose helical CT images were restored using the proposed model and 3 other restoration models (IRLNet, REDCNN and MWResNet), and the results were visually and quantitatively compared.@*RESULTS@#Quantitative comparisons of the restored images showed that the proposed helical CT projection data restoration model increased the structural similarity index by 5.79% to 17.46% compared with the other restoration algorithms (P < 0.05). The image quality scores of the proposed method rated by clinical radiologists ranged from 7.19% to 17.38%, significantly higher than the other restoration algorithms (P < 0.05).@*CONCLUSION@#The proposed method can effectively suppress noises and reduce artifacts in the projection data at different low-dose levels while preserving the integrity of the edges and fine details of the reconstructed CT images.


Subject(s)
Algorithms , Artifacts , Tomography, Spiral Computed , Tomography, X-Ray Computed/methods
3.
Journal of Southern Medical University ; (12): 832-839, 2022.
Article in Chinese | WPRIM | ID: wpr-941011

ABSTRACT

OBJECTIVE@#To propose an adaptive weighted CT metal artifact reduce algorithm that combines projection interpolation and physical correction.@*METHODS@#A normalized metal projection interpolation algorithm was used to obtain the initial corrected projection data. A metal physical correction model was then introduced to obtain the physically corrected projection data. To verify the effectiveness of the method, we conducted experiments using simulation data and clinical data. For the simulation data, the quantitative indicators PSNR and SSIM were used for evaluation, while for the clinical data, the resultant images were evaluated by imaging experts to compare the artifact-reducing performance of different methods.@*RESULTS@#For the simulation data, the proposed method improved the PSNR value by at least 0.2 dB and resulted in the highest SSIM value among the methods for comparison. The experiment with the clinical data showed that the imaging experts gave the highest scores of 3.616±0.338 (in a 5-point scale) to the images processed using the proposed method, which had significant better artifact-reducing performance than the other methods (P < 0.001).@*CONCLUSION@#The metal artifact reduction algorithm proposed herein can effectively reduce metal artifacts while preserving the tissue structure information and reducing the generation of new artifacts.


Subject(s)
Algorithms , Artifacts , Image Processing, Computer-Assisted/methods , Metals , Phantoms, Imaging , Tomography, X-Ray Computed/methods
4.
International Eye Science ; (12): 551-553, 2020.
Article in Chinese | WPRIM | ID: wpr-798299

ABSTRACT

@#AIM: To investigate the feasibility, effect and safety of endoscopic canaliculus opening operation with lacrimal drainage tube for proximal lacrimal duct obstruction.<p>METHODS: Totally 52 patients(61 eyes)with proximal lacrimal duct obstruction were examined in the Third Affiliated Hospital of Nanchang University from June 1 2016 to June 1 2018, and all were treated by endoscopic canaliculus opening operation with lacrimal drainage tube. Lacrimal drainage tube was removed after 2-3mo. All patients were followed up from 6-12(mean 7.3±2.2)mo. The operation effect and complications were observed.<p>RESULTS: All patients were treated by endoscopic canaliculus opening operation with lacrimal drainage tube successfully. The recovery rate was 85%, improvement rate was 8%, ineffective rate was 7%, effective rate was 93%. Without serious complications occurred after operation.<p>CONCLUSION: Endoscopic canaliculus opening operation with lacrimal drainage tube for treating the proximal lacrimal duct obstruction, could locate precisely and fully open the normal lacrimal duct with high success rate, safe and feasible.

5.
International Eye Science ; (12): 901-903, 2020.
Article in Chinese | WPRIM | ID: wpr-820918

ABSTRACT

@#AIM: To discuss the advantage, improvement, safety and effectiveness of improved endoscopic dacryocystorhinostomy in the treatment of chronic dacryocystitis.<p>METHODS: Eighty cases of chronic dacryocystitis with two different surgical methods were randomly selected and divided into common endoscopic dacryocystorhinostomy(80 cases with 82 eyes)and improved endoscopic dacryocystorhinostomy(80 cases with 84 eyes)according to operation. Compared to observe cure rate, improvement rate, total effective rate and patient satisfaction of two kinds of surgery by the last follow-up.<p>RESULTS: The cure rate, improvement rate, total effective rate and satisfaction rate were respectively 75.6%, 17.1%, 92.7% and 73.8% for Group A, 90.5%, 5.9%, 96.4% and 92.5% for Group B. Differences between the cure rate, improvement rate and total effective rate between two groups had statistical significance(<i>P</i><0.05).<p>CONCLUSION: The cure rate and improve symptom of improved endoscopic dacryocystorhinostomy is superior to the common endoscopic dacryocystorhinostomy, safe and effective.

6.
Chinese Journal of Hepatology ; (12): 451-454, 2005.
Article in Chinese | WPRIM | ID: wpr-348777

ABSTRACT

<p><b>OBJECTIVE</b>To study effects of insulin treatment on intracellular lipid content in livers and insulin resistance of type 2 diabetic rats.</p><p><b>METHODS</b>Type 2 diabetic rats were induced by injecting streptozotocin (25 mg/kg) and fat rich food. Then according to the results of the oral glucose tolerance test (OGTT) and glucose-induced insulin secretion test (IST), the rats were divided into two groups: control group (DC) and insulin treated group (DI). Normal rats (NC) served as controls. The treatment of each group with either NPH insulin (4 approximately 6 U . kg-1. d-1), or saline continued for 4 weeks. Body weight, OGTT, IST, blood lipids, intracellular lipids in liver and liver histology were studied. The insulin sensitivity index (ISI) was applied to assess the status of insulin resistance.</p><p><b>RESULTS</b>Blood lipid and intracellular lipids in livers in the DC were higher than those in NC (t = 2.59 approximately 15.77, P < 0.05) and the ISI was lower (t = 3.16, P < 0.05), with many fatty droplets appearing in the livers. In comparison to DC, DI showed that blood lipids were decreased, but lipids in livers were markedly increased (TG, TC, FFA increased 55.7%, 19.87%, 22.2%, respectively), and fatty droplets in hepatocytes were larger, but the ISI did not change significantly.</p><p><b>CONCLUSION</b>Insulin treatment can make blood glucose normal, increase the intracellular lipid content in the liver, and not increase the insulin resistance significantly.</p>


Subject(s)
Animals , Male , Rats , Diabetes Mellitus, Experimental , Drug Therapy , Metabolism , Diabetes Mellitus, Type 2 , Drug Therapy , Metabolism , Insulin , Therapeutic Uses , Insulin Resistance , Lipid Metabolism , Liver , Metabolism , Rats, Wistar
7.
Journal of Experimental Hematology ; (6): 240-242, 2001.
Article in Chinese | WPRIM | ID: wpr-258026

ABSTRACT

Objective is designed to observe the effect of the low molecular protein "SL Hong-Xin Blood-Increasing Capsules" on human iron deficiency anemia. Altogether 110 school children, 7 - 12 years old, with iron deficiency anemia (Hb < 120 g/L) were enrolled in this trial and were randomly and evenly divided into two groups. In the treatment group (n = 55), the "SL Hong-Xin Blood-Increasing Capsules" were orally adminitered for 30 days, two capsules at one time and two times a day, whereas in the control group (n = 55) blank capsules were given to the children in the same way as in the treatment group. Before and at the end of the trial period, peripheral blood samples were taken from fringers of the children to determine Hb content, hematocrit percentage, and free protoporphyrin content in red blood cells. Results showed that after trial the Hb content was (15.9 +/- 9.6) g/L in the treatment group, while that of the control group was only (5.3 +/- 4.3) g/L (P < 0.001). The hematocrit percentage markedly increased (P < 0.001) and protoporphyrin level markedly decreased (P < 0.001). In conclusion the active ingredient of "SL Hong-Xin Blood-Increasing Capsules" is low molecular protein iron, which is markedly effective for elevating Hb content and hematocrit percentage, and effective for decresing protoporphyrin content of children with iron deficiency anemia. Hence, the capsules could be used to improve nutritional anemia in children based on the "Functional Evaluation Procedure and Test Methods For Health-Care Food".

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