1.Machine Learning-Based Prediction of COVID-19 Severity and Progression to Critical Illness Using CT Imaging and Clinical Data
Subhanik PURKAYASTHA ; Yanhe XIAO ; Zhicheng JIAO ; Rujapa THEPUMNOEYSUK ; Kasey HALSEY ; Jing WU ; Thi My Linh TRAN ; Ben HSIEH ; Ji Whae CHOI ; Dongcui WANG ; Martin VALLIÈRES ; Robin WANG ; Scott COLLINS ; Xue FENG ; Michael FELDMAN ; Paul J. ZHANG ; Michael ATALAY ; Ronnie SEBRO ; Li YANG ; Yong FAN ; Wei-hua LIAO ; Harrison X. BAI
Korean Journal of Radiology 2021;22(7):1213-1224
Objective:
To develop a machine learning (ML) pipeline based on radiomics to predict Coronavirus Disease 2019 (COVID-19) severity and the future deterioration to critical illness using CT and clinical variables.
Materials and Methods:
Clinical data were collected from 981 patients from a multi-institutional international cohort with real-time polymerase chain reaction-confirmed COVID-19. Radiomics features were extracted from chest CT of the patients. The data of the cohort were randomly divided into training, validation, and test sets using a 7:1:2 ratio. A ML pipeline consisting of a model to predict severity and time-to-event model to predict progression to critical illness were trained on radiomics features and clinical variables. The receiver operating characteristic area under the curve (ROC-AUC), concordance index (C-index), and time-dependent ROC-AUC were calculated to determine model performance, which was compared with consensus CT severity scores obtained by visual interpretation by radiologists.
Results:
Among 981 patients with confirmed COVID-19, 274 patients developed critical illness. Radiomics features and clinical variables resulted in the best performance for the prediction of disease severity with a highest test ROC-AUC of 0.76 compared with 0.70 (0.76 vs. 0.70, p = 0.023) for visual CT severity score and clinical variables. The progression prediction model achieved a test C-index of 0.868 when it was based on the combination of CT radiomics and clinical variables compared with 0.767 when based on CT radiomics features alone (p < 0.001), 0.847 when based on clinical variables alone (p = 0.110), and 0.860 when based on the combination of visual CT severity scores and clinical variables (p = 0.549). Furthermore, the model based on the combination of CT radiomics and clinical variables achieved time-dependent ROC-AUCs of 0.897, 0.933, and 0.927 for the prediction of progression risks at 3, 5 and 7 days, respectively.
Conclusion
CT radiomics features combined with clinical variables were predictive of COVID-19 severity and progression to critical illness with fairly high accuracy.
2.Machine Learning-Based Prediction of COVID-19 Severity and Progression to Critical Illness Using CT Imaging and Clinical Data
Subhanik PURKAYASTHA ; Yanhe XIAO ; Zhicheng JIAO ; Rujapa THEPUMNOEYSUK ; Kasey HALSEY ; Jing WU ; Thi My Linh TRAN ; Ben HSIEH ; Ji Whae CHOI ; Dongcui WANG ; Martin VALLIÈRES ; Robin WANG ; Scott COLLINS ; Xue FENG ; Michael FELDMAN ; Paul J. ZHANG ; Michael ATALAY ; Ronnie SEBRO ; Li YANG ; Yong FAN ; Wei-hua LIAO ; Harrison X. BAI
Korean Journal of Radiology 2021;22(7):1213-1224
Objective:
To develop a machine learning (ML) pipeline based on radiomics to predict Coronavirus Disease 2019 (COVID-19) severity and the future deterioration to critical illness using CT and clinical variables.
Materials and Methods:
Clinical data were collected from 981 patients from a multi-institutional international cohort with real-time polymerase chain reaction-confirmed COVID-19. Radiomics features were extracted from chest CT of the patients. The data of the cohort were randomly divided into training, validation, and test sets using a 7:1:2 ratio. A ML pipeline consisting of a model to predict severity and time-to-event model to predict progression to critical illness were trained on radiomics features and clinical variables. The receiver operating characteristic area under the curve (ROC-AUC), concordance index (C-index), and time-dependent ROC-AUC were calculated to determine model performance, which was compared with consensus CT severity scores obtained by visual interpretation by radiologists.
Results:
Among 981 patients with confirmed COVID-19, 274 patients developed critical illness. Radiomics features and clinical variables resulted in the best performance for the prediction of disease severity with a highest test ROC-AUC of 0.76 compared with 0.70 (0.76 vs. 0.70, p = 0.023) for visual CT severity score and clinical variables. The progression prediction model achieved a test C-index of 0.868 when it was based on the combination of CT radiomics and clinical variables compared with 0.767 when based on CT radiomics features alone (p < 0.001), 0.847 when based on clinical variables alone (p = 0.110), and 0.860 when based on the combination of visual CT severity scores and clinical variables (p = 0.549). Furthermore, the model based on the combination of CT radiomics and clinical variables achieved time-dependent ROC-AUCs of 0.897, 0.933, and 0.927 for the prediction of progression risks at 3, 5 and 7 days, respectively.
Conclusion
CT radiomics features combined with clinical variables were predictive of COVID-19 severity and progression to critical illness with fairly high accuracy.
3.Estimation of Acute Infarct Volume with Reference Maps: A Simple Visual Tool for Decision Making in Thrombectomy Cases
Dong Eog KIM ; Wi Sun RYU ; Dawid SCHELLINGERHOUT ; Han‐Gil JEONG ; Paul KIM ; Sang Wuk JEONG ; Man Seok PARK ; Kang Ho CHOI ; Joon Tae KIM ; Beom Joon KIM ; Moon Ku HAN ; Jun LEE ; Jae Kwan CHA ; Dae Hyun KIM ; Hyun Wook NAH ; Soo Joo LEE ; Jae Guk KIM ; Keun Sik HONG ; Yong Jin CHO ; Hong Kyun PARK ; Byung Chul LEE ; Kyung Ho YU ; Mi Sun OH ; Jong Moo PARK ; Kyusik KANG ; Kyung Bok LEE ; Tai Hwan PARK ; Sang Soon PARK ; Yong Seok LEE ; Hee Joon BAE
Journal of Stroke 2019;21(1):69-77
BACKGROUND AND PURPOSE: Thrombectomy within 24 hours can improve outcomes in selected patients with a clinical-infarct mismatch. We devised an easy-to-use visual estimation tool that allows infarct volume estimation in centers with limited resources. METHODS: We identified 1,031 patients with cardioembolic or large-artery atherosclerosis infarction on diffusion-weighted images (DWIs) obtained before recanalization therapy and within 24 hours of onset, and occlusion of the internal carotid or middle cerebral artery. Acute DWIs were mapped onto a standard template and used to create visual reference maps with known lesion volumes, which were then used in a validation study (with 130 cases) against software estimates of infarct volume. RESULTS: The DWI reference map chart comprises 144 maps corresponding to 12 different infarct volumes (0.5, 1, 2, 3, 5, 7, 9, 11, 13, 15, 17, and 19 mL) in each of 12 template slices (Montreal Neurological Institute z-axis –15 to 51 mm). Infarct volume in a patient is estimated by selecting a slice with a similar infarct size at the corresponding z-axis level on the reference maps and then adding up over all slices. The method yielded good correlations to software volumetrics and was easily learned by both experienced and junior physicians, with approximately 1 to 2 minutes spent per case. The sensitivity, specificity, and accuracy for detecting threshold infarct volumes ( < 21, < 31, and < 51 mL) were very high (all about >90%). CONCLUSIONS: We developed easy-to-use reference maps that allow prompt and reliable visual estimation of infarct volumes for triaging patients to thrombectomy in acute stroke.
Atherosclerosis
;
Cerebral Infarction
;
Decision Making
;
Diffusion Magnetic Resonance Imaging
;
Humans
;
Infarction
;
Medical Staff, Hospital
;
Methods
;
Middle Cerebral Artery
;
Sensitivity and Specificity
;
Stroke
;
Thrombectomy
4.Association Between Vitamin D Insufficiency and Metabolic Syndrome in Patients With Psychotic Disorders.
Taeyoung YOO ; Wonsuk CHOI ; Jin Hee HONG ; Ju Yeon LEE ; Jae Min KIM ; Il Seon SHIN ; Soo Jin YANG ; Paul AMMINGER ; Michael BERK ; Jin Sang YOON ; Sung Wan KIM
Psychiatry Investigation 2018;15(4):396-401
OBJECTIVE: This study examined the association between vitamin D and metabolic syndrome in patients with psychotic disorders. METHODS: The study enrolled 302 community-dwelling patients with psychotic disorders. Sociodemographic and clinical characteristics, including blood pressure, physical activity, and dietary habit were gathered. Laboratory examinations included vitamin D, lipid profile, fasting plasma glucose, HbA1c, liver function, and renal function. Vitamin D insufficiency was defined as <20 ng/mL. Clinical characteristics associated with vitamin D insufficiency were identified. RESULTS: Among the 302 participants, 236 patients (78.1%) had a vitamin D insufficiency and 97 (32.1%) had metabolic syndrome. Vitamin D insufficiency was significantly associated with the presence of metabolic syndrome (p=0.006) and hypertension (p=0.017). Significant increases in triglycerides and alanine transaminase were observed in the group with a vitamin D insufficiency (p=0.002 and 0.011, respectively). After adjusting for physical activity and dietary habit scores, vitamin D insufficiency remained significantly associated with metabolic syndrome and hypertension. CONCLUSION: Vitamin D insufficiency was associated with metabolic syndrome and was particularly associated with high blood pressure, although the nature, direction and implications of this association are unclear.
Alanine Transaminase
;
Blood Glucose
;
Blood Pressure
;
Fasting
;
Food Habits
;
Humans
;
Hypertension
;
Liver
;
Motor Activity
;
Psychotic Disorders*
;
Schizophrenia
;
Triglycerides
;
Vitamin D*
;
Vitamins*
5.Diagnostic Value of Carcinoembryonic Antigen in Ascites for Colorectal Cancer with Peritoneal Carcinomatosis.
Sung Eun SONG ; Paul CHOI ; Jae Hyun KIM ; Kyoungwon JUNG ; Sung Eun KIM ; Won MOON ; Moo In PARK ; Seun Ja PARK
The Korean Journal of Gastroenterology 2018;71(6):332-337
BACKGROUND/AIMS: Diagnostic tests for carcinoembryonic antigen (CEA) in ascites have been performed in various malignant cases, but there is only few data on the applicability of CEA for colorectal cancer (CRC) patients with peritoneal carcinomatosis. We aimed to determine the usefulness of CEA in ascites (aCEA) as a diagnostic parameter for CRC with peritoneal carcinomatosis. METHODS: Between January 2000 and May 2013, the medical records of 259 patients who underwent paracentesis for the evaluation of ascites were retrospectively reviewed. CRC patients with ascites (n=82) and patients with non-malignant ascites (n=177) were evaluated. Patients who had other malignancies, including gastric or ovarian cancer, with ascites were excluded. The optimal diagnostic cut-off value of aCEA for CRC with peritoneal carcinomatosis was determined using receiver operating characteristic curve analysis. The value of aCEA for predicting the occurrence of peritoneal carcinomatosis was evaluated using a logistic regression model. RESULTS: The optimal cut-off value of aCEA to diagnose CRC with peritoneal carcinomatosis was 3.89 ng/mL, and the area under the curve for aCEA was 0.996 (sensitivity 96.3%, specificity 100%, positive predictive value 100%, negative predictive value 98.3%). Multivariate logistic regression analysis showed that aCEA was an independent factor predicting the occurrence of peritoneal carcinomatosis. CONCLUSIONS: In this study, we showed that aCEA may be a useful parameter for diagnosing CRC with peritoneal carcinomatosis, and we propose an optimal aCEA cut-off value of 3.89 ng/mL. Further study that includes patients with other malignant ascites may be necessary to validate these findings.
Ascites*
;
Carcinoembryonic Antigen*
;
Carcinoma*
;
Colorectal Neoplasms*
;
Diagnostic Tests, Routine
;
Humans
;
Logistic Models
;
Medical Records
;
Ovarian Neoplasms
;
Paracentesis
;
Peritoneal Neoplasms
;
Retrospective Studies
;
ROC Curve
;
Sensitivity and Specificity
6.Localization of Serum Amyloid A3 in the Mouse Ovary.
Hyeongjwa CHOI ; Rosa Mistica C. IGNACIO ; Eun Sook LEE ; Katherine F ROBY ; Paul F TERRANOVA ; Deok Soo SON
Immune Network 2017;17(4):261-268
Tumor necrosis factor-α (TNF-α) induces serum amyloid A (SAA) 3 among acute-phase proteins in mouse granulosa cells by activating NF-κB signaling via p55 TNF-α receptor type 1. However, the localization of SAA3 within the ovary is unknown. Here we investigated ovarian localization of SAA3 in a mouse ovulation model and in response to IL-1β, a proinflammatory mediator. For the ovulation model, equine chorionic gonadotropin (eCG; 2.5 IU) was administered to mice subcutaneously (sc) to stimulate follicular development on day 25 of age and then 50 h after eCG, human chorionic gonadotropin (hCG; 2.5 IU) was administered sc to induce ovulation. The mouse ovulation model was characterized by the localization of CYP19 mRNA expression to granulosa layers of larger follicles. SAA3 mRNA, determined by in situ hybridization, was broadly expressed throughout the whole ovary. Granulosa layers and small follicles expressed higher SAA3 mRNA compared to thecal-interstitial layers and large follicles, respectively. Interestingly, atretic follicles contained cells expressing intense SAA3 mRNA. After ovulation, SAA3 mRNA expression was intensely evident in ruptured follicles and corpora lutea (CL). The intraperitoneal administration of IL-1β revealed the intense and extensive appearance of specific cells expressing SAA3 mRNA around follicles and in CL. In addition, Gene Expression Omnibus (GEO) database analysis supported expression pattern of SAA3 mRNA observed in mouse ovulation model. Taken together, SAA3 was broadly distributed through the whole ovary, but intensely expressed in atretic follicles and CL. Furthermore, proinflammatory mediators could trigger the intense appearance of SAA3 around follicles and in CL.
Acute-Phase Proteins
;
Amyloid*
;
Animals
;
Aromatase
;
Chorionic Gonadotropin
;
Corpus Luteum
;
Electrocardiography
;
Female
;
Gene Expression
;
Granulosa Cells
;
In Situ Hybridization
;
Mice*
;
Necrosis
;
Ovarian Follicle
;
Ovary*
;
Ovulation
;
RNA, Messenger
;
Serum Amyloid A Protein
7.Epidemiology and Clinical Management of Traumatic Spine Injuries at a Major Government Hospital in Cambodia.
Jee Hye CHOI ; Paul J PARK ; Vuthy DIN ; Nang SAM ; Vycheth IV ; Kee B PARK
Asian Spine Journal 2017;11(6):908-916
STUDY DESIGN: Cross sectional study. PURPOSE: To characterize the pattern of injury, describe the current clinical management, and determine the outcomes in traumatic spine injury (TSI) patients presenting to a major government hospital in Phnom Penh, Cambodia. OVERVIEW OF LITERATURE: There is a paucity of literature on epidemiology or current clinical practices for TSIs in Cambodia. The findings from this study can thus serve as a valuable resource for future progress in treating TSIs in low-income countries. METHODS: This study was a cross-sectional study of TSI patients admitted to Preah Kossamak Hospital in Phnom Penh, Cambodia. Demographics, cause of spinal injury, spinal level of injury, surgical procedures and techniques, complications, and American Spinal Injury Association (ASIA) grades were recorded and analyzed. RESULTS: Eighty patients were admitted with TSI between October 2013 and June 2014. Falls from heights were the most common cause of TSI, followed by road traffic accidents. 78% of the admitted patients underwent at least one surgical procedure. Without intraoperative imaging, 4 patients (6%) had wrong level surgery, and 1 patient (2%) had misplacement of pedicle screws. Sacral decubitus ulcers were the most common non-surgically related complication. Antibiotics were administered to >90% of patients. There were no in-hospital mortalities. Of the 60 spinal cord injury (SCI) patients, 32% (19/60) showed improvement in their ASIA grade at the time of discharge, and 52% (31/60) showed no change. At follow-up, 32% (19/60) of SCI patients reported improvement, and 8% (5/60) reported no change. However, 36 SCI patients (60%) were lost to follow-up. CONCLUSIONS: Despite technological limitations, outcomes of TSI patients in Cambodia appear favorable with evidence of clinical improvement and low mortality.
Accidental Falls
;
Accidents, Traffic
;
Anti-Bacterial Agents
;
Asia
;
Cambodia*
;
Cross-Sectional Studies
;
Demography
;
Epidemiology*
;
Follow-Up Studies
;
Global Health
;
Hospital Mortality
;
Humans
;
Intraoperative Complications
;
Lost to Follow-Up
;
Mortality
;
Neurosurgical Procedures
;
Pedicle Screws
;
Pressure Ulcer
;
Spinal Cord Injuries
;
Spinal Injuries
;
Spine*
8.Accuracy of Ultrasound-Guided and Non-ultrasound-Guided Botulinum Toxin Injection Into Cadaver Salivary Glands.
Jae In SO ; Dae Heon SONG ; Joo Hyun PARK ; Eunseok CHOI ; Jung Yoon YOON ; Yeonji YOO ; Myung Eun CHUNG
Annals of Rehabilitation Medicine 2017;41(1):51-57
OBJECTIVE: To compare the accuracy of ultrasound (US)-guided and non-US-guided botulinum toxin (BTX) injection into the salivary glands (parotid and submandibular glands) of cadavers. METHODS: Two rehabilitation physician injected dye into three sites in the salivary glands (two sites in the parotid gland and one site in the submandibular gland) on one side of each cadaver (one was injected on the right side, while the other was injected on the left side), using either a non-US-guided injection procedure based on superficial landmarks or a US-guided procedure. Orange dye was used for the US-guided procedure, and green dye was used for the blind procedure. Two physicians uninvolved with the injection procedures and who were blinded to the method of injection dissected the cadavers to identify whether the dye was accurately injected into each target site. RESULTS: The accuracies of the blind and US-guided injections into the parotid gland were 79.17% and 95.83%, respectively. In the submandibular gland, the accuracies of the blind and US-guided injections were 50.00% and 91.67%, respectively. The difference in accuracy between the two procedures was statistically significant only in the submandibular gland (p=0.025). There were no significant differences in the accuracy of US-guided and non-US-guided injections between the two physicians for the two sites in the parotid gland (p=0.278 and p=0.146, respectively). CONCLUSION: US-guided BTX injection into the submandibular gland offers significantly greater accuracy over blind injection. For the treatment of drooling by injecting BTX into the submandibular gland, clinicians should consider using US guidance for improved accuracy.
Botulinum Toxins*
;
Cadaver*
;
Citrus sinensis
;
Methods
;
Parotid Gland
;
Rehabilitation
;
Salivary Glands*
;
Sialorrhea
;
Submandibular Gland
;
Ultrasonography
9.Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate in Asian Subjects with Human Immunodeficiency Virus 1 Infection: A Sub-Analysis of Phase 3 Clinical Trials.
Jun Yong CHOI ; Somnuek SUNGKANUPARPH ; Thanomsak ANEKTHANANON ; Paul SAX ; Edwin DEJESUS ; Howard EDELSTEIN ; Mark NELSON ; Jennifer DEMORIN ; Hui C LIU ; Raji SWAMY ; Joonwoo BAHN ; SunJin HWANG ; Sang Youn YANG ; Christopher NG ; David PIONTKOWSKY
Infection and Chemotherapy 2016;48(3):219-224
The efficacy and safety of a single tablet regimen (STR) of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF) were analyzed in Phase 3 clinical trials in antiretroviral therapy (ART)-naïve and ART-experienced Asian subjects infected with human immunodeficiency virus (HIV)-1. Studies GS-US-236-102 and GS-US-236-103 were randomized, double-blind, placebo-controlled, 144-week studies conducted in ART-naïve subjects, comparing E/C/F/TDF versus efavirenz (EFV)/F/TDF or ritonavir-boosted atazanavir (ATV+RTV) plus emtricitabine/tenofovir DF (F/TDF), respectively. Studies GS-US-236-115 and GS-US-236-121 were randomized, open-label, 96-week long conducted in ART-experienced subjects, who switched to E/C/F/TDF from ritonavir-boosted protease inhibitors (PI+RTV)+F/TDF, or non-nucleoside reverse transcriptase inhibitors (NNRTI)+F/TDF regimens. The E/C/F/TDF appeared to have sustained efficacy and safety and was well tolerated in the small number of ART-naïve and ART-experienced Asian subjects.
Asian Continental Ancestry Group*
;
Atazanavir Sulfate
;
HIV*
;
HIV-1*
;
Humans
;
Humans*
;
Protease Inhibitors
;
Reverse Transcriptase Inhibitors
10.Physiological and Functional Magnetic Resonance Imaging Using Balanced Steady-state Free Precession.
Sung Hong PARK ; Paul Kyu HAN ; Seung Hong CHOI
Korean Journal of Radiology 2015;16(3):550-559
Balanced steady-state free precession (bSSFP) is a highly efficient pulse sequence that is known to provide the highest signal-to-noise ratio per unit time. Recently, bSSFP is getting increasingly popular in both the research and clinical communities. This review will be focusing on the application of the bSSFP technique in the context of probing the physiological and functional information. In the first part of this review, the basic principles of bSSFP are briefly covered. Afterwards, recent developments related to the application of bSSFP, in terms of physiological and functional imaging, are introduced and reviewed. Despite its long development history, bSSFP is still a promising technique that has many potential benefits for obtaining high-resolution physiological and functional images.
Cervical Vertebrae/*blood supply/radiography
;
Head/*blood supply/radiography
;
Humans
;
Image Processing, Computer-Assisted/*methods
;
Magnetic Resonance Imaging/*methods
;
Signal-To-Noise Ratio

Result Analysis
Print
Save
E-mail