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1.
Article En | MEDLINE | ID: mdl-36901338

In the last few years, many types of research have been conducted on the most harmful pandemic, COVID-19. Machine learning approaches have been applied to investigate chest X-rays of COVID-19 patients in many respects. This study focuses on the deep learning algorithm from the standpoint of feature space and similarity analysis. Firstly, we utilized Local Interpretable Model-agnostic Explanations (LIME) to justify the necessity of the region of interest (ROI) process and further prepared ROI via U-Net segmentation that masked out non-lung areas of images to prevent the classifier from being distracted by irrelevant features. The experimental results were promising, with detection performance reaching an overall accuracy of 95.5%, a sensitivity of 98.4%, a precision of 94.7%, and an F1 score of 96.5% on the COVID-19 category. Secondly, we applied similarity analysis to identify outliers and further provided an objective confidence reference specific to the similarity distance to centers or boundaries of clusters while inferring. Finally, the experimental results suggested putting more effort into enhancing the low-accuracy subspace locally, which is identified by the similarity distance to the centers. The experimental results were promising, and based on those perspectives, our approach could be more flexible to deploy dedicated classifiers specific to different subspaces instead of one rigid end-to-end black box model for all feature space.


COVID-19 , Datasets as Topic , Deep Learning , X-Rays , Humans , Algorithms , Mass Chest X-Ray
2.
Medicine (Baltimore) ; 98(19): e15200, 2019 May.
Article En | MEDLINE | ID: mdl-31083152

Breast cancer is one of the most harmful diseases for women with the highest morbidity. An efficient way to decrease its mortality is to diagnose cancer earlier by screening. Clinically, the best approach of screening for Asian women is ultrasound images combined with biopsies. However, biopsy is invasive and it gets incomprehensive information of the lesion. The aim of this study is to build a model for automatic detection, segmentation, and classification of breast lesions with ultrasound images. Based on deep learning, a technique using Mask regions with convolutional neural network was developed for lesion detection and differentiation between benign and malignant. The mean average precision was 0.75 for the detection and segmentation. The overall accuracy of benign/malignant classification was 85%. The proposed method provides a comprehensive and noninvasive way to detect and classify breast lesions.


Breast Neoplasms/classification , Breast Neoplasms/diagnostic imaging , Image Interpretation, Computer-Assisted/methods , Ultrasonography, Mammary , Humans , Neural Networks, Computer , Pattern Recognition, Automated , Retrospective Studies , Ultrasonography, Mammary/methods
3.
Clin Nucl Med ; 37(5): e121-3, 2012 May.
Article En | MEDLINE | ID: mdl-22475923

A 56-year-old woman with breast cancer underwent FDG PET/CT at follow-up. The PET images showed increased FDG uptake along right sacroiliac joint. The coregistered CT images showed diffuse sclerosis around the sacroiliac joints, but no bony destruction, periarticular erosion, or joint space narrowing. She had been complaining of intermittent lower back pain since her last pregnancy. The radiologic pictures and history of postpartum back pain were considered as typical characteristics for osteitis condensans ilii. This case reminds us that careful inspection of the coregistered CT images is important to avoid potential misinterpretation because of osteitis condensans ilii.


Breast Neoplasms/complications , Fluorodeoxyglucose F18 , Image Processing, Computer-Assisted , Multimodal Imaging , Osteitis/complications , Osteitis/diagnostic imaging , Positron-Emission Tomography , Sacroiliac Joint/diagnostic imaging , Tomography, X-Ray Computed , Diagnostic Errors , Female , Humans , Middle Aged
4.
Clin Nucl Med ; 35(10): 808-10, 2010 Oct.
Article En | MEDLINE | ID: mdl-20838294

We report the case of a 57-year-old woman with the history of stage IB cervical cancer. She was found to have a metastatic squamous cell carcinoma in sigmoid colon. FDG PET/CT was then performed for whole-body cancer work-up. Intense FDG activity accumulated in the sigmoid tumor, with an unusually high SUVmax of 72.42, and was seen downwardly connected with the activity of urinary bladder on PET images. On the coregistered CT images, irregular wall thickening was noted for both sigmoid colon and urinary bladder with a hypodensity tract communicating with each other. It was concluded that recurrent cervical cancer involving urinary bladder and sigmoid colon resulted in colovesical fistula.


Fluorodeoxyglucose F18 , Intestinal Fistula/diagnostic imaging , Positron-Emission Tomography , Tomography, X-Ray Computed , Uterine Cervical Neoplasms/complications , Female , Humans , Intestinal Fistula/complications , Middle Aged , Recurrence , Uterine Cervical Neoplasms/diagnostic imaging
5.
BMC Gastroenterol ; 10: 81, 2010 Jul 14.
Article En | MEDLINE | ID: mdl-20630083

BACKGROUND: Hemobilia is a rare but lethal biliary tract complication. There are several causes of hemobilia which might be classified as traumatic or nontraumatic. Hemobilia caused by pseudoaneurysm might result from hepatobiliary surgery or percutaneous interventional hepatobiliary procedures. However, to our knowledge, there are no previous reports pertaining to hemobilia caused by hepatic pseudoaneurysm after T-tube choledochostomy. CASE PRESENTATION: A 65-year-old male was admitted to our hospital because of acute calculous cholecystitis and cholangitis. He underwent cholecystectomy, choledocholithotomy via a right upper quadrant laparotomy and a temporary T-tube choledochostomy was created. However, on the 19th day after operation, he suffered from sudden onset of hematemesis and massive fresh blood drainage from the T-tube choledochostomy. Imaging studies confirmed the diagnosis of pseudoaneurysm associated hemobilia. The probable association of T-tube choledochostomy with pseudoaneurysm and hemobilia is also demonstrated. He underwent emergent selective microcoils emobolization to occlude the feeding artery of the pseudoaneurysm. CONCLUSIONS: Pseudoaneurysm associated hemobilia may occur after T-tube choledochostomy. This case also highlights the importance that hemobilia should be highly suspected in a patient presenting with jaundice, right upper quadrant abdominal pain and upper gastrointestinal bleeding after liver or biliary surgery.


Aneurysm, False/complications , Aneurysm, False/etiology , Choledochostomy/adverse effects , Hemobilia/etiology , Hepatic Artery , Aged , Cholangitis/surgery , Cholecystectomy , Cholecystitis, Acute/surgery , Choledochostomy/methods , Hemobilia/diagnosis , Humans , Male
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