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1.
Diabetic retinopathy (DR) is one of the most important complications of diabetes. Accurate segmentation of DR lesions is of great importance for the early diagnosis of DR. However, simultaneous segmentation of multi-type DR lesions is technically challenging because of 1) the lack of pixel-level annotations and 2) the large diversity between different types of DR lesions. In this study, first, we propose a novel Poisson-blending data augmentation (PBDA) algorithm to generate synthetic images, which can be easily utilized to expand the existing training data for lesion segmentation. We perform extensive experiments to recognize the important attributes in the PBDA algorithm. We show that position constraints are of great importance and that the synthesis density of one type of lesion has a joint influence on the segmentation of other types of lesions. Second, we propose a convolutional neural network architecture, named DSR-U-Net++ (i.e., DC-SC residual U-Net++), for the simultaneous segmentation of multi-type DR lesions. Ablation studies showed that the mean area under precision recall curve (AUPR) for all four types of lesions increased by >5% with PBDA. The proposed DSR-U-Net++ with PBDA outperformed the state-of-the-art methods by 1.7%-9.9% on the Indian Diabetic Retinopathy Image Dataset (IDRiD) and 67.3% on the e-ophtha dataset with respect to mean AUPR. The developed method would be an efficient tool to generate large-scale task-specific training data for other medical anomaly segmentation tasks. 相似文献
2.
《Journal of Medical Imaging and Radiation Sciences》2022,53(3):444-452
Background/PurposeMen undergoing radiation therapy (RT) treatment for prostate cancer (PC) often experience acute urinary, bowel, sexual, and hormonal toxicities. Timely screening, management, and documentation of these toxicities is an integral part of clinician practice, ensuring patients receive the care they require. Various screening tools, completed by either the patient or the clinician, are available, which allow clinicians to collect and respond to these toxicity outcomes; however there is a paucity of literature regarding the effective use and timing of these tools during RT treatment. This study aims to evaluate the feasibility of conducting comprehensive toxicity screening and symptom management using a toxicity screening tool in one of the busiest RT departments in Canada. Specifically, the use of a toxicity screening tool and its effect on the quality of toxicity documentation, operational impact, and patient reported outcomes (PRO).Methods90 consented patients were allocated to either the structured or non-structured arm. Patients in the structured arm were assessed weekly by radiation therapists for 13 toxicities across four domains (bladder, bowel, hormonal, and sexual), using an in-house developed structured questionnaire, known as the Grid, to complete the National Cancer Institute's Common Toxicity Criteria for Adverse Events v3 (CTCAEv3). Patients in the non-structured arm were assessed and had free text clinical documentation charted according to current department policy. The Expanded Prostate Cancer Index Composite (EPIC), a PRO tool to evaluate patient function and bother after prostate cancer treatment, was completed by all study patients on a weekly basis. Statistical analysis compared documentation completeness, EPIC scores, patient satisfaction, and operational impact between study arms, as well as evaluated optimal timing of toxicity assessments.ResultsAssessment of the non-structured arm for completeness revealed an inconsistent and insufficient amount of documentation for the bladder and bowel domains. As for both the sexual and hormonal domains, documentation was largely absent. There was no difference in EPIC scores and patient satisfaction scores between the structured arm and the non-structured arm. Evaluation of the timing of PROs showed significant week to week change for the bladder and bowel toxicities, but not the sexual and hormonal toxicities. Finally, the use of the Grid revealed no significant impact on daily operations, only increasing average treatment times by seven seconds, and did not create any additional workload for the oncologists.ConclusionsUse of the Grid increased documentation completeness without negatively impacting clinical flow or operations, despite the fact that PROs were not improved. Based on EPIC PRO scores, bladder and bowel toxicities should be evaluated on a weekly basis during RT treatment, while sexual and hormonal toxicities need only be evaluated monthly. 相似文献
3.
《Journal of Medical Imaging and Radiation Sciences》2022,53(3):460-470
PurposeTo provide means for calculating the dose received by various tissues of the patient, calculate lung shield, and verify received dose using a phantom as a tool for quality assurance for a planned Total Body Irradiation (TBI) procedure in radiotherapy.MethodUsing Microsoft Visual Basic, MATLAB, and Python, a program for Total Body Irradiation Calculation in Radiotherapy (TBICR) is constructed. It uses patient translation and beam zone method for total body irradiation calculations to compute the proper dose received by the patient and determine the lung shield thickness. There are three main user-friendly interfaces in the application. The first one allows the user to upload the TBI topography and estimate the distances needed for TBI calculations. The second one enables the user to count the number of beam zones needed for each point and estimate the effective area (Aeff) for each level. The third interface estimates the velocity required to deliver the relative dose depending on patient separation, Monitor Units (MU), couch speed and travel distance. It allows the user to compute the required lung shield thickness, read any patient's CT DICOM file and acquire dose in any distinct location using machine learning model to predict the dose.ResultsThe TBICR software has been successfully validated by reproducing all of the manual calculations in an exact and timely manner. TBICR generated more accurate results and confirmed the absorbed dose to patient through measurements on Anderson phantom.ConclusionsA computer program for the calculation of total body irradiation (TBI) is described in full. The dose received at each point on the patient, the calculation of lung shield and the determination of the velocity and time required for the couch movement are all made possible using the software. The ease of use, precision, data storage and printing are some important features of the present software. 相似文献
4.
5.
《Journal of manipulative and physiological therapeutics》2022,45(4):290-297
ObjectiveThe purpose of the study was to investigate pulmonary functions of patients with chronic neck pain and compare them with those of asymptomatic controls.MethodsThis case-control study was conducted with 25 patients with chronic neck pain (age, 26.84 ± 7.89 years) and 27 age-matched asymptomatic controls (age, 25.96 ± 7.13 years). Pulmonary function tests were performed using spirometry (Quark PFT, COSMED, Rome, Italy). Forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), forced expiratory flow at 25% to 75% vital capacity, peak expiratory flow, maximum voluntary ventilation, and the FEV1/FVC ratio were measured and are expressed as (%) predicted value for patients with chronic neck pain and asymptomatic controls.ResultsThe chronic neck pain group had lower FEV1 (P = .015), FVC (P = .029), forced expiratory flow at 25% to 75% vital capacity (P = .040), and maximum voluntary ventilation (P = .042) compared with asymptomatic controls; however, FEV1/FVC (P = .470) and peak expiratory flow (P = .183) were similar in both groups.ConclusionThese results demonstrated that dynamic lung volumes were lower in patients with chronic neck pain compared with asymptomatic controls. 相似文献
6.
A 2-year-old girl was diagnosed as Weill-Marchesani syndrome with typical systemic features of short stature, short and stubby hands and feet, language disorders and mental retardation. He developed bilateral angle closure glaucoma, ectopia lentis and suffered visual loss from the ocular features of Weill-Marchesani syndrome. The child was successfully treated by combined CO2 laser-assisted sclerectomy surgery and trabeculectomy. 相似文献
7.
Knee cartilage defects caused by osteoarthritis are major musculoskeletal disorders, leading to joint necrosis or even disability if not intervened at early stage. Deep learning has demonstrated its effectiveness in computer-aided diagnosis, but it is time-consuming to prepare a large set of well-annotated data by experienced radiologists for model training. In this paper, we propose a semi-supervised framework to effectively use unlabeled data for better evaluation of knee cartilage defect grading. Our framework is developed based on the widely-used mean-teacher classification model, by designing a novel dual-consistency strategy to boost the consistency between the teacher and student models. The main contributions are three-fold: (1) We define an attention loss function to make the network focus on the cartilage regions, which can both achieve accurate attention masks and boost classification performance simultaneously; (2) Besides enforcing the consistency of classification results, we further design a novel attention consistency mechanism to ensure the focusing of the student and teacher networks on the same defect regions; (3) We introduce an aggregation approach to ensemble the slice-level classification outcomes for deriving the final subject-level diagnosis. Experimental results show that our proposed method can significantly improve both classification and localization performances of knee cartilage defects. Our code is available on https://github.com/King-HAW/DC-MT. 相似文献
8.
目的:探讨消化道肿瘤中同源重组修复相关基因(homologous recombination repair related gene,HRR)突变的发生情况及临床意义。方法:共92例消化道肿瘤患者,79例患者进行了血液标本HRR检测,53例患者进行了组织标本HRR检测,40例患者同时行血液和组织的HRR基因检测,收集患者基因检测结果及临床相关资料。结果:在79例患者血液标本检测中发现10例(12.6%)有临床意义HRR突变,在53例患者组织标本检测中发现9例(17.0%)有临床意义HRR突变。40例同时行血液和组织的HRR基因检测患者中常见的有临床意义HRR突变为CDK12突变4例(10.0%)、ATM突变3例(7.5%)、BRCA1突变2例(5.0%)。13例有临床意义HRR突变患者中常见共存突变为TP53突变10例(76.9%)、APC突变5例(38.5%)、PIK3CA突变4例(30.8%)。40例患者中13例患者血液和/或组织中有临床意义HRR突变,27例患者血液和组织中均无任何临床意义HRR突变且两组相比,有临床意义HRR突变组肿瘤突变负荷(tumor mutational burden,TMB)为6.17(2.24~11.52),而未携带HRR突变组TMB为0.4(0~3.75),差异有统计学意义(P<0.05)。40例患者组织检测中7例HRR有临床意义的突变,33例无HRR突变,血液检测中10例HRR有临床意义的突变,30例无HRR突变,一致性检验的Kappa值为0.333(P=0.031)。结论:携带有临床意义HRR突变的消化道肿瘤患者TMB更高,血液和组织检测HRR突变有较好的一致性。 相似文献
9.
《Journal of diabetes and its complications》2022,36(8):108260
AimTo verify whether arterial stiffness and endothelial dysfunction influence lower limb muscle strength and gait speed in older adults with type 2 diabetes mellitus (T2DM).MethodsCross-sectional study including seventy-eight older adults with T2DM (aged 67 ± 6 years and 42 % male). Arterial stiffness was assessed using pulse wave velocity (PWV), while endothelial function was measured by flow-mediated dilation (FMD). Lower limb muscle strength and gait speed were assessed using the 30-second chair stand test (30s-CST) and 10-Meter Walk Test, respectively.ResultsBoth PWV (m/s) and FMD (%) were univariately associated with number of repetitions in 30s-CST and gait speed (P < 0.05). After control for age, sex and body mass index, PWV remained associated with repetitions in 30s-CST (95 % CI: ?0.494 to ?0.054; P = 0.015) and gait speed (95 % CI: ?0.039 to ?0.002; P = 0.031). After adjustments for control variables, T2DM duration and glycemic control, FMD was associated with repetitions in 30s-CST (95 % CI: 0.008 to 0.324; P = 0.039) and gait speed (95 % CI: 0.011 to 0.038; P = 0.001).ConclusionIn older adults with T2DM, both arterial stiffness and endothelial dysfunction are associated with decreased leg muscle strength and slower gait speed. 相似文献
10.
The research and development of penicillin started with difficulty before 1949 and achieved certain results. In 1951, after the founding of the People's Republic of China, Zhang Weishen, as the only Chinese scientist who had been trained and worked in a penicillin research and development center in the United States for many years, overcame many difficulties and returned to China. In 1953, with the efforts of Zhang Weishen and his colleagues, China realized the industrialized production of penicillin, alleviating the urgent needs of the masses. Antibiotics has also become the first discipline to achieve major scientific and technological achievements after the founding of the New China. In the mid-1950s, the technical breakthrough in the localization of lactose substitutes marked the localization of the raw materials of the penicillin-producing culture medium, which paved the way for the industrialized production of penicillin with Chinese characteristics. Antibiotics have become one of the most widely used and affordable drugs for hundreds of millions of patients in China, and China has since ended the humiliating history of the “Sick Man of East Asia". 相似文献