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find Keyword "calcification" 15 results
  • A case of perivalvular leakage and attempt of closure operation after transcatheter aortic valve replacement

    This paper reported a 75-year-old female patient. She was admitted to our hospital for “repeated chest pain, shortness of breath for more than 5 years, and syncope 3 times”. The CT scan of the patient showed severe aortic valve stenosis, bicuspid valve, and severe calcification; then she underwent transcatheter aortic valve replacement in our hospital. After the prosthesis was implanted, there was a significant paravalvular leak. Considering the triangular area formed between the calcified clumps, the valve was not fully dilated. Paravalvular leak closure was performed during the operation, attempted through the valve stent mesh to closuring. A rare incarceration of the transmitter occurred. An attempt was made to pull out the incarcerated transmitter through a pull-up technique, which resulted in the prosthesis prolapse. The patient was eventually transferred to surgery aortic valve replacement.

    Release date:2020-05-26 02:34 Export PDF Favorites Scan
  • Surgical resection of space occupying with extensive calcification of pancreatic head

    ObjectiveTo estimate the prognosis of duodenum-preserving resection of pancreatic head (DPRPH) in the treatment of space occupying with extensive calcification of pancreatic head, and to summarize the key points of surgery.MethodsThe clinical data of a middle-aged woman with rare space occupying with extensive calcification of pancreatic head who underwent surgery in Department of Pancreatic Surgery of West China Hospital in May. 2016 was collected and analyzed.ResultsThe DPRPH operation was successfully completed, with the operative time was 207 min, the intraoperative blood loss was 130 mL, and the hospital stay was 12 d. Removing time of the gastric tube and off-bed activity were on the 3rd day after operation, and the volume of peritoneal drainage per day was decreasing from 30 mL to 10 mL until 7th day after operation. We made examination of serum amylase and fluid amylase for the patient every 2 days, and the examination indexes were within normal level. After removing the peritoneal drainage tube, the pain was obviously relieved on the 12th day after operation, then the patient made hospital discharge. There was no observable pancreatic fistula, duodenal fistula, biliary fistula, delay gastric emptying, peritoneal effusion, pleural effusion, abdominal infection, and abdominal bleeding, neither nor any special discomfort. During the follow-up period of 18 months, we got a good prognosis without any symptom of relapse or discomfort according to the result of CT scans and other examinations.ConclusionDPRPH can make a satisfied prognosis in the treatment of rare space occupying with extensive calcification of pancreatic head.

    Release date:2019-01-16 10:05 Export PDF Favorites Scan
  • Detection of microcalcification clusters regions in mammograms combining discriminative deep belief networks

    In order to overcome the shortcomings of high false positive rate and poor generalization in the detection of microcalcification clusters regions, this paper proposes a method combining discriminative deep belief networks (DDBNs) to automatically and quickly locate the regions of microcalcification clusters in mammograms. Firstly, the breast region was extracted and enhanced, and the enhanced breast region was segmented to overlapped sub-blocks. Then the sub-block was subjected to wavelet filtering. After that, DDBNs model for breast sub-block feature extraction and classification was constructed, and the pre-trained DDBNs was converted to deep neural networks (DNN) using a softmax classifier, and the network is fine-tuned by back propagation. Finally, the undetected mammogram was inputted to complete the location of suspicious lesions. By experimentally verifying 105 mammograms with microcalcifications from the Digital Database for Screening Mammography (DDSM), the method obtained a true positive rate of 99.45% and a false positive rate of 1.89%, and it only took about 16 s to detect a 2 888 × 4 680 image. The experimental results showed that the algorithm of this paper effectively reduced the false positive rate while ensuring a high positive rate. The detection of calcification clusters was highly consistent with expert marks, which provides a new research idea for the automatic detection of microcalcification clusters area in mammograms.

    Release date:2021-06-18 04:50 Export PDF Favorites Scan
  • Research progress between ferroptosis and vascular calcification

    Vascular calcification is an active, adjustable and complex biological process. It is an independent hazard factor for cardiovascular events and there is a lack of effective treatment. As a newly discovered regulated cell death, ferroptosis is closely related to iron metabolism, lipid metabolism, glutathione metabolism and so on. In recent years, studies have shown that ferroptosis may be implicated in the occurrence and progression of vascular calcification. Based on the introduction of ferroptosis, this review will discuss the close relationship between ferroptosis and vascular calcification from intimal calcification, medial calcification and heart valve calcification, in order to provide new ideas for the prevention and treatment of vascular calcification.

    Release date:2023-03-17 09:43 Export PDF Favorites Scan
  • Transcatheter aortic valve replacement for severe aortic valve stenosis via carotid approach: a case report

    This case was an elderly male patient with symptomatic aortic valve calcification and severe aortic valve stenosis. Before the operation, the heart valve team had fully evaluated the patient’s suitability for transcatheter aortic valve replacement and approach. This patient had severe stenosis and plaques in the iliac artery, femoral artery, descending aorta, so the carotid artery approach transcatheter aortic valve replacement was chosen. After the operation, the patient’s symptoms improved significantly. So far, the patient was generally in good condition, without chest tightness, shortness of breath and other symptoms in daily activities. The current clinical application of the transcarotid approach is relatively small, but it is believed that with the publication of more clinical research results, the application of the transcarotid approach in transcatheter aortic valve replacement will become more and more common.

    Release date:2020-10-26 03:00 Export PDF Favorites Scan
  • A New Type of Anticalcification Bovine Jugular Venous Conduit

    Abstract: Objective To evaluate a new type of treatment that reduces calcification of glutaraldehydetreated bovine jugular venous conduit (BJVC). Methods Fresh bovine jugular veins were treated with glutaraldehyde, followed by Triton X-100 and epoxy chloropropane (EC+Tr group). We compared the group’s appearance, histology, shrinkage temperature, tensile strength, and elongation at break with those of a fresh group, and with a group treated with glutaraldehyde only (GA group). We then implanted the EC+Tr and GA group BJVCs subcutaneously into the backs of SD rats and left them for eight weeks (n=8). The morphologic properties and inflammatory response of the test specimens were evaluated by HE staining. The tissue calcium content was determined by atomic absorption spectrophotometer. Results The shrinkage temperature, tensile strength, and elongation at break of the EC+Tr group were significantly higher than those of the fresh group (86.15±0.92 ℃ vs. 69.94±0.92 ℃,t=35.239, P=0.000; 5.31±0.14 mPa vs.3.15±0.95 mPa,t=6.362, P=0.000; 265.11%±27.80% vs. 16521%±25.06%,t=7.550, P=0.000) and of the GA group (86.15±0.92 ℃ vs. 82.73±1.28 ℃, t=6.137, P=0.000; 5.31±0.14 mPa vs. 4.52±0.56 mPa,t=3.871, P=0.002; 265.11%±27.80% vs.237.85%±17.41%,t=2.351,P=0.034). The tissue structure of the subcutaneously implanted EC+Tr veins remained intact;degradation was slight and they contained few inflammatory cells. The calcium content of the EC+Tr group was lower than that of the GA group (51.22±2.69 μg/mg vs. 73.24±3.82 μg/mg, t=11.545,P=0.000). Conclusion Treatment with Triton X-100 and epoxy chloropropane modification with glutaraldehydetreated bovine jugular venous conduit was an effective way to prepare BJVC that avoided calcification.

    Release date:2016-08-30 05:57 Export PDF Favorites Scan
  • Soft tissue calcifications and ossifications observed by means of panoramic radiography

    Soft tissue opacities are often found by chance during radiographic examinations, especially in panoramic radiography. Because of the diversity of locations and causes, it is easily overlooked by dentists and even radiologists. Even if abnormal calcification is detected, it is difficult to identify its category and clinical relevance. For some soft tissue opacities associated with high-risk diseases, misdiagnosis is likely to delay treatment. Through reviewing the literature and screening the panoramic images from the disease database of West China Hospital of Stomatology, Sichuan University, this review summarizes and classifies the soft tissue opacities appearing in panoramic images, and discusses the clinical correlation to provide the reference for diagnosis, treatment, and prevention of related diseases.

    Release date:2019-06-25 09:50 Export PDF Favorites Scan
  • Research progress of mechanisms of sclerostin in vascular calcification and atherosclerotic heart disease

    Sclerostin, as a bone-derived secreted glycoprotein, is a suppressor of Wnt signaling pathway. Recently, adverse cardiovascular events in the treatment of osteoporosis with sclerostin inhibitors have raised concerns about the association of sclerostin with atherosclerotic heart disease. Whether the role of sclerostin in atherosclerotic heart disease is harmful or beneficial is not clear. This article reviews the progress of the mechanisms of sclerostin in vascular calcification and atherosclerotic heart disease, focusing on the relationship between sclerostin and vascular calcification, the impact of its concentration changes on atherosclerotic heart disease, and the effect of sclerostin inhibitor on cardiovascular events.

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  • Research progress of serum alkaline phosphatase in cardiovascular disease

    Serum alkaline phosphatase (ALP) has long been used as a biomarker for the liver, kidney, and bone. Currently, increasing evidence suggests a correlation between serum ALP and cardiovascular disease (CVD). Research has shown that serum ALP affects endothelial cell function and induces changes in pyrophosphate through various mechanisms to accelerate vascular calcification and promote cardiac fibrosis. Therefore, this article reviews the potential value of serum ALP in CVD through relevant research, revealing the specific relationship between serum ALP and CVD, in order to provide new ideas for the prevention and treatment of CVD.

    Release date:2024-05-28 01:17 Export PDF Favorites Scan
  • Extraction of calcification in ultrasonic images based on convolution neural network

    Ultrasound is the best way to diagnose thyroid nodules. To discriminate benign and malignant nodules, calcification is an important characteristic. However, calcification in ultrasonic images cannot be extracted accurately because of capsule wall and other internal tissue. In this paper, deep learning was first proposed to extract calcification, and two improved methods were proposed on the basis of Alexnet convolutional neural network. First, adding the corresponding anti-pooling (unpooling) and deconvolution layers (deconv2D) made the network to be trained for the required features and finally extract the calcification feature. Second, modifying the number of convolution templates and full connection layer nodes made feature extraction more refined. The final network was the combination of two improved methods above. To verify the method presented in this article, we got 8 416 images with calcification, and 10 844 without calcification. The result showed that the accuracy of the calcification extraction was 86% by using the improved Alexnet convolutional neural network. Compared with traditional methods, it has been improved greatly, which provides effective means for the identification of benign and malignant thyroid nodules.

    Release date:2018-10-19 03:21 Export PDF Favorites Scan
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