Factors associated with the incidence of revision total knee arthroplasty in Korea between 2007 and 2012: an analysis of the National Claim Registry

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Abstract Background The number of revision total knee arthroplasties (TKAs) in Asian countries is projected to increase with the rapid growth of primary TKA. We investigated the factors associated with the incidence of revision TKA using a nationally representative database. Methods Data collected by the Health Insurance Review Agency of Korea, from 260,068 TKA patients between 2007 and 2012, were used to estimate the incidence rate and cumulative incidence of revision TKA according to age, gender, and hospital TKA and prosthesis manufacturer volume. Age, hospital, and manufacturer volume were categorized into three groups. The incidence rates and cumulative incidences of revision TKA were computed by combining age and gender, and by combining hospital and prosthesis manufacturer volume. Results Incidence rates per 100,000 person-years were as follows: 1) by age: < 65 years, 447.2; 65–74 years, 363.7; ≥ 75 years, 270.9, 2) by gender: male, 537.8; female, 346.1; 3) by hospital volume (procedures/year): < 20, 536.9; 20–199, 432.3; ≥ 200, 300.1; and 4) by manufacturer volume (prostheses/year): < 1500, 772.3; 1500–3999, 453.9; ≥ 4000, 345.6. The revision TKA incidence rate in young males was significantly higher compared to that in elderly females. The difference in cumulative incidence, between hospitals with an annual volume of < 20 procedures and those with a volume of 20–199 procedures, was reduced for manufacturers with an annual volume of ≥ 4000. Similarly, the difference in cumulative incidence between manufacturers with an annual volume of <1500 prostheses and those with a volume of 1500–3999 prostheses was reduced in hospitals with an annual volume of ≥ 200. Conclusion Revision TKA incidence varied according to age, gender, and hospital and manufacturer volume. This data could inform clinical decisions and healthcare strategies

Genomic alterations of primary tumor and blood in invasive ductal carcinoma of breast

<p>Abstract</p> <p>Background</p> <p>Genomic alterations are important events in the origin and progression of various cancers, with DNA copy number changes associated with progression and treatment response in cancer. Array CGH is potentially useful in the identification of genomic alterations from primary tumor and blood in breast cancer patients. The aim of our study was to compare differences of DNA copy number changes in blood and tumor tissue in breast cancer.</p> <p>Methods</p> <p>DNA copy number changes in blood were compared to those in tumor tissue using array-comparative genomic hybridization in samples obtained from 30 breast cancer patients. The relative degree of chromosomal changes was analyzed using log2 ratios and data was validated by real-time polymerase chain reaction.</p> <p>Results</p> <p>Forty-six regions of gains present in more than 30% of the tissues and 70 regions of gains present in more than 30% of blood were identified. The most frequently gained region was chromosome 8q24. In total, agreement of DNA copy numbers between primary tumor and blood was minimal (Kappa = 0.138, p < 0.001).</p> <p>Conclusion</p> <p>Although there was only a slight agreement of DNA copy number alterations between the primary tumor and the blood samples, the blood cell copy number variation may have some clinical significance as compared to the primary tumor in IDC breast cancer patients.</p

Development of a Rating System for Digestive System Impairments: Korean Academy of Medical Sciences Guideline

A systematic and effective welfare system for people with digestive system impairments is required. In Korea, an objective and scientific rating guideline does not exist to judge the digestive system impairments. Whether the impairments exist or not and the degree of it need to be examined. Thus, with these considerations we need a scientific rating guideline for digestive system impairments to fit our cultural and social background. In 2007, a research team, for the development of rating impairment guidelines, was organized under the supervision of Korean Academy of Medical Sciences. The rating guidelines for digestive system impairments was classified into upper and lower gastrointestinal tracts impairments and liver impairment. We developed objective rating guidelines for the upper gastrointestinal tract, the impairment generated after surgery for the stomach, duodenum, esophagus, and for the lower gastrointestinal tract, the impairment generated after construction and surgery for colon, rectum, anus, and intestinal stomas. We tried to make the rating impairment guidelines to include science, objectivity, convenience, rationality, and actuality. We especially emphasized objectivity as the most important value. We worked to make it easy and convenient to use for both the subjects who received the impairment ratings and the doctors who will give the ratings

Deep learning for prediction of mechanism in acute ischemic stroke using brain diffusion magnetic resonance image

Background Acute ischemic stroke is a disease with multiple etiologies. Therefore, identifying the mechanism of acute ischemic stroke is fundamental to its treatment and secondary prevention. The Trial of Org 10172 in Acute Stroke Treatment classification is currently the most widely used system, but it often has a limitations of classifying unknown causes and inadequate inter-rater reliability. Therefore, we attempted to develop a three-dimensional (3D)-convolutional neural network (CNN)-based algorithm for stroke lesion segmentation and subtype classification using only the diffusion and apparent diffusion coefficient information of patients with acute ischemic stroke. Methods This study included 2,251 patients with acute ischemic stroke who visited our hospital between February 2013 and July 2019. Results The segmentation model for lesion segmentation in the training set achieved a Dice score of 0.843±0.009. The subtype classification model achieved an average accuracy of 81.9%, with accuracies of 81.6% for large artery atherosclerosis, 86.8% for cardioembolism, 72.9% for small vessel occlusion, and 86.3% for control. Conclusion We developed a model to predict the mechanism of cerebral infarction using diffusion magnetic resonance imaging, which has great potential for identifying diffusion lesion segmentation and stroke subtype classification. As deep learning systems are gradually developing, they are becoming useful in clinical practice and applications

Craniopharyngioma in the Temporal Lobe: A Case Report

Herein, we report on an unusual case of craniopharyngioma arising in the temporal lobe with no prior history of surgery and with no connection to the craniopharyngeal duct. MR images showed a cystic tumor with a small solid portion. To the best of our knowledge, this is the first case of a craniopharyngioma occurring in the temporal lobe

Polymeric tandem organic light-emitting diodes using a self-organized interfacial layer

The authors have demonstrated efficient polymeric tandem organic light-emitting diodes (OLEDs) with a self-organized interfacial layer, which was formed by differences in chemical surface energy. Hydrophilic poly(styrene sulfonate)-doped poly(3,4-ethylene dioxythiophene) (PEDOT:PSS) was spin coated onto the hydrophobic poly(9,9-dyoctilfluorene) (PFO) surface and a PEDOT:PSS bubble or dome was built as an interfacial layer. The barrier heights of PEDOT:PSS and PFO in the two-unit tandem OLED induced a charge accumulation at the interface in the heterojunction and thereby created exciton recombination at a much higher level than in the one-unit reference. This effect was confirmed in both the hole only and the electron only devices. (c) 2008 American Institute of Physicsopen8

The natural history of pediatric trigger thumb

BACKGROUND: Pediatric trigger thumb is a condition of flexion deformity of the interphalangeal joint in children. Although the surgical outcome is satisfactory, the indications for nonoperative treatment for this condition are not clear. The aim of the present study was to determine the rate of resolution of untreated pediatric trigger thumb. METHODS: Data on seventy-one thumbs in fifty-three children were collected prospectively. The dates of the first visits ranged from April 1994 to March 2004. Patients were diagnosed with pediatric trigger thumb during initial outpatient department visits. During the present study, no treatment such as passive stretching or splinting was applied. The amount of flexion deformity at the thumb interphalangeal joint was measured at every six-month follow-up visit, and the duration of follow-up was at least two years after diagnosis. The end point of follow-up was when the deformity caused pain or secondary deformity or prevented normal use of the hand. The median duration of follow-up was forty-eight months. RESULTS: Of the seventy-one trigger thumbs, forty-five (63%) resolved spontaneously. The median time from the initial visit to resolution was forty-eight months. There was no significant difference in the pattern of resolution between patients with unilateral and bilateral trigger thumb. Although resolution was not observed in the remaining twenty-six thumbs, flexion deformities improved in twenty-two thumbs. For the first two years after the initial visit, the mean flexion deformity significantly decreased over the one-year intervals (p 60% of patients. Moreover, the flexion deformity can be expected to show an improving pattern in patients who do not have resolution. This information may help both parents and surgeons to make decisions regarding the treatment of pediatric trigger thumb

Assessment of a novel deep learning-based software developed for automatic feature extraction and grading of radiographic knee osteoarthritis

Background The Kellgren-Lawrence (KL) grading system is the most widely used method to classify the severity of osteoarthritis (OA) of the knee. However, due to ambiguity of terminology, the KL system showed inferior inter- and intra-observer reliability. For a more reliable evaluation, we recently developed novel deep learning (DL) software known as MediAI-OA to extract each radiographic feature of knee OA and to grade OA severity based on the KL system. Methods This research used data from the Osteoarthritis Initiative for training and validation of MediAI-OA. 44,193 radiographs and 810 radiographs were set as the training data and used as validation data, respectively. This AI model was developed to automatically quantify the degree of joint space narrowing (JSN) of medial and lateral tibiofemoral joint, to automatically detect osteophytes in four regions (medial distal femur, lateral distal femur, medial proximal tibia and lateral proximal tibia) of the knee joint, to classify the KL grade, and present the results of these three OA features together. The model was tested by using 400 test datasets, and the results were compared to the ground truth. The accuracy of the JSN quantification and osteophyte detection was evaluated. The KL grade classification performance was evaluated by precision, recall, F1 score, accuracy, and Cohen's kappa coefficient. In addition, we defined KL grade 2 or higher as clinically significant OA, and accuracy of OA diagnosis were obtained. Results The mean squared error of JSN rate quantification was 0.067 and average osteophyte detection accuracy of the MediAI-OA was 0.84. The accuracy of KL grading was 0.83, and the kappa coefficient between the AI model and ground truth was 0.768, which demonstrated substantial consistency. The OA diagnosis accuracy of this software was 0.92. Conclusions The novel DL software known as MediAI-OA demonstrated satisfactory performance comparable to that of experienced orthopedic surgeons and radiologists for analyzing features of knee OA, KL grading and OA diagnosis. Therefore, reliable KL grading can be performed and the burden of the radiologist can be reduced by using MediAI-OA