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1.
J Med Internet Res ; 25: e42717, 2023 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-36795468

RESUMEN

BACKGROUND: An artificial intelligence (AI) model using chest radiography (CXR) may provide good performance in making prognoses for COVID-19. OBJECTIVE: We aimed to develop and validate a prediction model using CXR based on an AI model and clinical variables to predict clinical outcomes in patients with COVID-19. METHODS: This retrospective longitudinal study included patients hospitalized for COVID-19 at multiple COVID-19 medical centers between February 2020 and October 2020. Patients at Boramae Medical Center were randomly classified into training, validation, and internal testing sets (at a ratio of 8:1:1, respectively). An AI model using initial CXR images as input, a logistic regression model using clinical information, and a combined model using the output of the AI model (as CXR score) and clinical information were developed and trained to predict hospital length of stay (LOS) ≤2 weeks, need for oxygen supplementation, and acute respiratory distress syndrome (ARDS). The models were externally validated in the Korean Imaging Cohort of COVID-19 data set for discrimination and calibration. RESULTS: The AI model using CXR and the logistic regression model using clinical variables were suboptimal to predict hospital LOS ≤2 weeks or the need for oxygen supplementation but performed acceptably in the prediction of ARDS (AI model area under the curve [AUC] 0.782, 95% CI 0.720-0.845; logistic regression model AUC 0.878, 95% CI 0.838-0.919). The combined model performed better in predicting the need for oxygen supplementation (AUC 0.704, 95% CI 0.646-0.762) and ARDS (AUC 0.890, 95% CI 0.853-0.928) compared to the CXR score alone. Both the AI and combined models showed good calibration for predicting ARDS (P=.079 and P=.859). CONCLUSIONS: The combined prediction model, comprising the CXR score and clinical information, was externally validated as having acceptable performance in predicting severe illness and excellent performance in predicting ARDS in patients with COVID-19.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Síndrome de Dificultad Respiratoria , Humanos , Inteligencia Artificial , COVID-19/diagnóstico por imagen , Estudios Longitudinales , Estudios Retrospectivos , Radiografía , Oxígeno , Pronóstico
4.
J Korean Med Sci ; 35(46): e413, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33258333

RESUMEN

BACKGROUND: The Korean Society of Thoracic Radiology (KSTR) recently constructed a nation-wide coronavirus disease 2019 (COVID-19) database and imaging repository, referred to the Korean imaging cohort of COVID-19 (KICC-19) based on the collaborative efforts of its members. The purpose of this study was to provide a summary of the clinico-epidemiological data and imaging data of the KICC-19. METHODS: The KSTR members at 17 COVID-19 referral centers retrospectively collected imaging data and clinical information of consecutive patients with reverse transcription polymerase chain reaction-proven COVID-19 in respiratory specimens from February 2020 through May 2020 who underwent diagnostic chest computed tomography (CT) or radiograph in each participating hospital. RESULTS: The cohort consisted of 239 men and 283 women (mean age, 52.3 years; age range, 11-97 years). Of the 522 subjects, 201 (38.5%) had an underlying disease. The most common symptoms were fever (n = 292) and cough (n = 245). The 151 patients (28.9%) had lymphocytopenia, 86 had (16.5%) thrombocytopenia, and 227 patients (43.5%) had an elevated CRP at admission. The 121 (23.4%) needed nasal oxygen therapy or mechanical ventilation (n = 38; 7.3%), and 49 patients (9.4%) were admitted to an intensive care unit. Although most patients had cured, 21 patients (4.0%) died. The 465 (89.1%) subjects underwent a low to standard-dose chest CT scan at least once during hospitalization, resulting in a total of 658 CT scans. The 497 subjects (95.2%) underwent chest radiography at least once during hospitalization, which resulted in a total of 1,475 chest radiographs. CONCLUSION: The KICC-19 was successfully established and comprised of 658 CT scans and 1,475 chest radiographs of 522 hospitalized Korean COVID-19 patients. The KICC-19 will provide a more comprehensive understanding of the clinical, epidemiological, and radiologic characteristics of patients with COVID-19.


Asunto(s)
COVID-19/diagnóstico por imagen , Radiografía Torácica/métodos , SARS-CoV-2 , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/terapia , Niño , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
5.
AJR Am J Roentgenol ; 209(5): 1015-1022, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28898127

RESUMEN

OBJECTIVE: The purposes of this study were to investigate dual-energy CT findings predictive of clinical outcome and to determine the incremental risk stratification benefit of dual-energy CT findings compared with CT ventricular diameter ratio in patients with acute pulmonary embolism. MATERIALS AND METHODS: A retrospective evaluation was conducted of the cases of 172 patients with acute pulmonary embolism who underwent dual-energy CT. Ventricular diameter ratio and relative perfusion defect volume were measured. The primary endpoints were death within 30 days and pulmonary embolism-related death. RESULTS: A ventricular diameter ratio of 1 or greater was associated with increased risk of death within 30 days (hazard ratio, 3.822; p = 0.002) and pulmonary embolism-related death (hazard ratio, 18.051; p < 0.001). Relative perfusion defect volume was also associated with increased risk of death of any cause within 30 days (hazard ratio, 1.044; p = 0.014) and pulmonary embolism-related death (hazard ratio, 1.046; p = 0.017). However, the addition of relative perfusion defect volume to ventricular diameter ratio had no added benefit for prediction of death of any cause within 30 days (concordance statistic, 0.833 vs 0.815; p = 0.187) or pulmonary embolism-related death (concordance statistic, 0.873 vs 0.874; p = 0.866). CONCLUSION: Compared with ventricular diameter ratio alone, lung perfusion defect volume had no statistically significant added benefit for prediction of death of any cause within 30 days or of pulmonary embolism-related death among patients with acute PE.


Asunto(s)
Angiografía , Embolia Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Circulación Pulmonar , Embolia Pulmonar/mortalidad , Embolia Pulmonar/terapia , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
6.
J Korean Med Sci ; 29(1): 23-31, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24431901

RESUMEN

Recent studies suggest that the intracoronary administration of bone marrow (BM)-derived mesenchymal stem cells (MSCs) may improve left ventricular function in patients with acute myocardial infarction (AMI). However, there is still argumentative for the safety and efficacy of MSCs in the AMI setting. We thus performed a randomized pilot study to investigate the safety and efficacy of MSCs in patients with AMI. Eighty patients with AMI after successful reperfusion therapy were randomly assigned and received an intracoronary administration of autologous BM-derived MSCs into the infarct related artery at 1 month. During follow-up period, 58 patients completed the trial. The primary endpoint was changes in left ventricular ejection fraction (LVEF) by single-photon emission computed tomography (SPECT) at 6 month. We also evaluated treatment-related adverse events. The absolute improvement in the LVEF by SPECT at 6 month was greater in the BM-derived MSCs group than in the control group (5.9% ± 8.5% vs 1.6% ± 7.0%; P=0.037). There was no treatment-related toxicity during intracoronary administration of MSCs. No significant adverse cardiovascular events occurred during follow-up. In conclusion, the intracoronary infusion of human BM-derived MSCs at 1 month is tolerable and safe with modest improvement in LVEF at 6-month follow-up by SPECT. (ClinicalTrials.gov registration number: NCT01392105).


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos/efectos adversos , Trasplante de Células Madre Mesenquimatosas/efectos adversos , Células Madre Mesenquimatosas/citología , Infarto del Miocardio/terapia , Adulto , Anciano , Células de la Médula Ósea/citología , Ecocardiografía , Femenino , Corazón/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Volumen Sistólico , Tomografía Computarizada de Emisión de Fotón Único , Trasplante Autólogo , Resultado del Tratamiento , Función Ventricular Izquierda , Adulto Joven
7.
Emerg Med J ; 30(8): 615-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22833601

RESUMEN

OBJECTIVES: This study was conducted to determine the proper hand position on the sternum for external chest compression to generate a maximal haemodynamic effect during cardiopulmonary resuscitation (CPR). METHODS: 114 patients with cardiac arrest who underwent chest CT after successful resuscitation from January 2006 to August 2009 were included in the study. To evaluate the area of the cardiac chambers subjected to external chest compression, the area of each cardiac chamber under the sternum was measured using cross-sectional CT at three different locations: the internipple line on the sternum (point A), halfway between point A and the sternoxiphoid junction (point B) and at the sternoxiphoid junction (point C). RESULTS: The widest total heart area, total ventricular area and left ventricular area (LVA) were observed most frequently at point C (58%, 85% and 78% of all cases, respectively). Few cases (six in total heart area, one in total ventricular area and one in LVA) were observed as the widest at point A. Predicted compressed areas of the right and left ventricle were wider at point C than at points A or B (right ventricular area: 366±536 mm(2) at point A, 961±653 mm(2) at point B and 1383±689 mm(2) at point C, p<0.001; LVA: 65±236 mm(2) at point A, 365±506 mm(2) at point B and 1099±817 mm(2) at point C, p<0.001). CONCLUSIONS: Only a small proportion of the ventricle is subjected to external chest compression when CPR is performed according to the current guidelines. Compression of the sternum at the sternoxiphoid junction might be more effective to compress the ventricles.


Asunto(s)
Reanimación Cardiopulmonar/métodos , Paro Cardíaco/terapia , Corazón/anatomía & histología , Postura , Reanimación Cardiopulmonar/normas , Femenino , Masaje Cardíaco/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esternón/anatomía & histología , Tomografía Computarizada por Rayos X
8.
Korean J Radiol ; 24(8): 807-820, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37500581

RESUMEN

OBJECTIVE: To assess whether computed tomography (CT) conversion across different scan parameters and manufacturers using a routable generative adversarial network (RouteGAN) can improve the accuracy and variability in quantifying interstitial lung disease (ILD) using a deep learning-based automated software. MATERIALS AND METHODS: This study included patients with ILD who underwent thin-section CT. Unmatched CT images obtained using scanners from four manufacturers (vendors A-D), standard- or low-radiation doses, and sharp or medium kernels were classified into groups 1-7 according to acquisition conditions. CT images in groups 2-7 were converted into the target CT style (Group 1: vendor A, standard dose, and sharp kernel) using a RouteGAN. ILD was quantified on original and converted CT images using a deep learning-based software (Aview, Coreline Soft). The accuracy of quantification was analyzed using the dice similarity coefficient (DSC) and pixel-wise overlap accuracy metrics against manual quantification by a radiologist. Five radiologists evaluated quantification accuracy using a 10-point visual scoring system. RESULTS: Three hundred and fifty CT slices from 150 patients (mean age: 67.6 ± 10.7 years; 56 females) were included. The overlap accuracies for quantifying total abnormalities in groups 2-7 improved after CT conversion (original vs. converted: 0.63 vs. 0.68 for DSC, 0.66 vs. 0.70 for pixel-wise recall, and 0.68 vs. 0.73 for pixel-wise precision; P < 0.002 for all). The DSCs of fibrosis score, honeycombing, and reticulation significantly increased after CT conversion (0.32 vs. 0.64, 0.19 vs. 0.47, and 0.23 vs. 0.54, P < 0.002 for all), whereas those of ground-glass opacity, consolidation, and emphysema did not change significantly or decreased slightly. The radiologists' scores were significantly higher (P < 0.001) and less variable on converted CT. CONCLUSION: CT conversion using a RouteGAN can improve the accuracy and variability of CT images obtained using different scan parameters and manufacturers in deep learning-based quantification of ILD.


Asunto(s)
Enfisema , Enfermedades Pulmonares Intersticiales , Enfisema Pulmonar , Femenino , Humanos , Persona de Mediana Edad , Anciano , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Pulmón/diagnóstico por imagen
9.
Sci Rep ; 12(1): 4932, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35322148

RESUMEN

Aging and atherosclerotic progression can lead to geometric changes in the carotid arteries. We conducted a longitudinal study to investigate geometric changes in the bilateral carotid arteries. We conducted a retrospective study of 177 subjects who underwent carotid contrast-enhanced magnetic resonance angiography (MRA) at our clinic at baseline and 10 years after the procedure. Semi-automated methods were used to segment the bilateral carotid arteries to obtain carotid artery geometric measurements. The mean age for the total population after 10 years was 70.7 ± 10.6 years (male, 40.1%). The mean time interval between baseline and after 10 years for all subjects was 130.2 ± 8.1 months. The bilateral bifurcation angle, the diameters for both common carotid arteries (CCAs), and areas of both CCAs significantly increased (p < 0.001) over a 10-year period. The maximum diameter and internal carotid artery area did not significantly change. The bifurcation angle of the right carotid artery was significantly increased compared to the left carotid artery. However, the diameter and area of the CCA of the left carotid artery was significantly increased compared to the right carotid artery. The bifurcation angle, diameter and area of both CCAs significantly increased over a decade. The change in the bifurcation angle over a 10-year period was predominant in the right carotid artery and the change of the area and diameter of the CCA was dominant in the left carotid artery.


Asunto(s)
Arterias Carótidas , Angiografía por Resonancia Magnética , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/patología , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/patología , Niño , Humanos , Estudios Longitudinales , Angiografía por Resonancia Magnética/métodos , Masculino , Estudios Retrospectivos
10.
Korean J Radiol ; 22(5): 829-839, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33686817

RESUMEN

OBJECTIVE: To compare the diagnostic performance of contrast-enhanced radial T1-weighted gradient-echo 3-tesla (3T) magnetic resonance imaging (MRI) and computed tomography (CT) for the detection of visceral pleural surface invasion (VPSI). Visceral pleural invasion by non-small-cell lung cancer (NSCLC) can be classified into two types: PL1 (without VPSI), invasion of the elastic layer of the visceral pleura without reaching the visceral pleural surface, and PL2 (with VPSI), full invasion of the visceral pleura. MATERIALS AND METHODS: Thirty-three patients with pathologically confirmed VPSI by NSCLC were retrospectively reviewed. Multidetector CT and contrast-enhanced 3T MRI with a free-breathing radial three-dimensional fat-suppressed volumetric interpolated breath-hold examination (VIBE) pulse sequence were compared in terms of the length of contact, angle of mass margin, and arch distance-to-maximum tumor diameter ratio. Supplemental evaluation of the tumor-pleura interface (smooth versus irregular) could only be performed with MRI (not discernible on CT). RESULTS: At the tumor-pleura interface, radial VIBE MRI revealed a smooth margin in 20 of 21 patients without VPSI and an irregular margin in 10 of 12 patients with VPSI, yielding an accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and F-score for VPSI detection of 91%, 83%, 95%, 91%, 91%, and 87%, respectively. The McNemar test and receiver operating characteristics curve analysis revealed no significant differences between the diagnostic accuracies of CT and MRI for evaluating the contact length, angle of mass margin, or arch distance-to-maximum tumor diameter ratio as predictors of VPSI. CONCLUSION: The diagnostic performance of contrast-enhanced radial T1-weighted gradient-echo 3T MRI and CT were equal in terms of the contact length, angle of mass margin, and arch distance-to-maximum tumor diameter ratio. The advantage of MRI is its clear depiction of the tumor-pleura interface margin, facilitating VPSI detection.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Imagen por Resonancia Magnética , Anciano , Área Bajo la Curva , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neoplasias Pleurales/diagnóstico , Neoplasias Pleurales/diagnóstico por imagen , Neoplasias Pleurales/secundario , Curva ROC , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
11.
Thorac Cancer ; 12(6): 941-948, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33554473

RESUMEN

BACKGROUND: Ongoing studies are currently investigating the extent of surgical resection required for subsolid cancers. This study aimed to investigate the predictive factors related to recurrence in patients with clinical stage IA subsolid cancer who underwent either lobectomy or sublobar resection. METHODS: This was a prospective multicenter observational study conducted in eight qualifying university teaching hospitals between April 2014 and December 2016. A total of 173 patients with subsolid nodules pathologically confirmed to have primary lung adenocarcinoma and stage IA disease were included in the final analysis. All patients underwent lobectomy, segmentectomy, or wedge resection performed by experienced thoracoscopic surgeons at each site. The surgical procedure was chosen based on the decision of the surgeons involved. The primary endpoint was time to recurrence (TTR). RESULTS: The study population was 43.9% (76 of 173) male with a mean age of 60.7 years. During the median follow-up period of 5.01 years, nine patients (5%) experienced disease recurrence. In the multivariable analysis, tumor size (size ≥2 cm) (hazard ratio: 73.717, 95% confidence interval [CI]: 3.635-895.036; p < 0.001) and stage IA3 (hazard ratio: 62.010, 95% CI: 2.837-855.185; p < 0.001) were independent predictors of tumor recurrence. When analyzing the recurrence outcome in patients according to surgical procedure, no significant difference was found in TTR among the three groups (i.e., lobectomy, segmentectomy, and wedge resection; p = 0.99). CONCLUSIONS: Patients with radiologically subsolid lung adenocarcinoma measuring <3 cm could be candidates for sublobar resection instead of lobectomy.


Asunto(s)
Adenocarcinoma del Pulmón/cirugía , Neoplasias Pulmonares/cirugía , Adenocarcinoma del Pulmón/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Prospectivos
12.
J Thorac Cardiovasc Surg ; 159(4): 1571-1579.e2, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31735392

RESUMEN

OBJECTIVES: Accurate and safe preoperative localization is useful for video-assisted thoracic surgery of small pulmonary lesions with ground-glass opacity (GGO). However, the optimal localization method is unclear. The aim of this study was to compare the usefulness and safety of the lipiodol and hook-wire localization techniques for video-assisted thoracic surgery of GGO lesions. METHODS: This prospective, non-randomized comparative study was conducted between April 2014 and December 2016 at 8 qualifying university teaching hospitals. Two-hundred-fifty patients with pulmonary lesions having GGO were included. Patients were assigned in a 1:1 ratio to either the lipiodol (n = 125, 4 hospitals) or hook-wire group (n = 125, 4 hospitals) for preoperative localization procedures. Participants underwent preoperative localization via the lipiodol or hook-wire technique followed by thoracoscopic surgery. The primary endpoint was the procedure success rate. RESULTS: The procedure success rates (hook-wire vs lipiodol group) were 94.40% versus 99.16% (P = .08). Localization-related complications occurred in 53.60% versus 48.33% of patients (P = .49). Hemorrhage rates were significantly greater in the hook-wire group than in the lipiodol group (21.6% vs 5.83%, P < .001). The lipiodol procedure time was significantly longer than that of the hook-wire technique (20.69 ± 9.34 vs 17.15 ± 7.91 minutes, P = .001). The initially positive surgical resection margin was significantly greater in the hook-wire group than in the lipiodol group (10.89% vs 2.38%, P = .02). CONCLUSIONS: There was no significant difference in success rate between the hook-wire and lipiodol methods. However, the hemorrhage rate was significantly greater in the hook-wire group, whereas the hook-wire group showed greater initially positive surgical resection margins.


Asunto(s)
Antineoplásicos/uso terapéutico , Aceite Etiodizado/uso terapéutico , Neoplasias Pulmonares/terapia , Complicaciones Posoperatorias/epidemiología , Nódulo Pulmonar Solitario/terapia , Cirugía Torácica Asistida por Video/métodos , Anciano , Medios de Contraste , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Cirugía Torácica Asistida por Video/efectos adversos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
13.
Arch Pharm Res ; 31(2): 188-94, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18365689

RESUMEN

To further understand the significance of bone as a target tissues of lead toxicity, as well as a reservoir of systemic lead, it is necessary to define the effect of lead on the calcium release activated calcium influx (CRACI) in primary cultures of human osteoblast-like cells (OLC). Pb2+ inhibited the immediate CRACI dose-dependent manner. Influx of Pb2+ into human OLC was increased dose-dependent manner. The present study demonstrates that the interference of Pb2+ with CRACI of human OLC is at least twofold: (1) the initiation of CRACI, i.e., the measurable influx of Ca2+ upon Ca2+ readdition, is partially inhibited by Pb2+ and (2) the influx of Pb2+ was enhanced after CRACI had been induced.


Asunto(s)
Calcio/metabolismo , Plomo/farmacología , Osteoblastos/metabolismo , Calcimicina/farmacología , Canales de Calcio/metabolismo , Células Cultivadas , Interpretación Estadística de Datos , Inhibidores Enzimáticos/farmacología , Humanos , Indicadores y Reactivos , Ionóforos/farmacología , Osteoblastos/efectos de los fármacos , Soluciones , Tapsigargina/farmacología
14.
Med Phys ; 45(5): 1871-1888, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29500855

RESUMEN

PURPOSE: This work describes the hardware and software developments of a prototype chest digital tomosynthesis (CDT) R/F system. The purpose of this study was to validate the developed system for its possible clinical application on low-dose chest tomosynthesis imaging. METHODS: The prototype CDT R/F system was operated by carefully controlling the electromechanical subsystems through a synchronized interface. Once a command signal was delivered by the user, a tomosynthesis sweep started to acquire 81 projection views (PVs) in a limited angular range of ±20°. Among the full projection dataset of 81 images, several sets of 21 (quarter view) and 41 (half view) images with equally spaced angle steps were selected to represent a sparse view condition. GPU-accelerated and total-variation (TV) regularization strategy-based compressed sensing (CS) image reconstruction was implemented. The imaged objects were a flat-field using a copper filter to measure the noise power spectrum (NPS), a Catphan® CTP682 quality assurance (QA) phantom to measure a task-based modulation transfer function (MTFTask ) of three different cylinders' edge, and an anthropomorphic chest phantom with inserted lung nodules. The authors also verified the accelerated computing power over CPU programming by checking the elapsed time required for the CS method. The resultant absorbed and effective doses that were delivered to the chest phantom from two-view digital radiographic projections, helical computed tomography (CT), and the prototype CDT system were compared. RESULTS: The prototype CDT system was successfully operated, showing little geometric error with fast rise and fall times of R/F x-ray pulse less than 2 and 10 ms, respectively. The in-plane NPS presented essential symmetric patterns as predicted by the central slice theorem. The NPS images from 21 PVs were provided quite different pattern against 41 and 81 PVs due to aliased noise. The voxel variance values which summed all NPS intensities were inversely proportional to the number of PVs, and the CS method gave much lower voxel variance by the factors of 3.97-6.43 and 2.28-3.36 compared to filtered backprojection (FBP) and 20 iterations of simultaneous algebraic reconstruction technique (SART). The spatial frequencies of the f50 at which the MTFTask reduced to 50% were 1.50, 1.55, and 1.67 cycles/mm for FBP, SART, and CS methods, respectively, in the case of Bone 20% cylinder using 41 views. A variety of ranges of TV reconstruction parameters were implemented during the CS method and we could observe that the NPS and MTFTask preserved best when the regularization and TV smoothing parameters α and τ were in a range of 0.001-0.1. For the chest phantom data, the signal difference to noise ratios (SDNRs) were higher in the proposed CS scheme images than in the FBP and SART, showing the enhanced rate of 1.05-1.43 for half view imaging. The total averaged reconstruction time during 20 iterations of the CS scheme was 124.68 s, which could match-up a clinically feasible time (<3 min). This computing time represented an enhanced speed 386 times greater than CPU programming. The total amounts of estimated effective doses were 0.12, 0.53 (half view), and 2.56 mSv for two-view radiographs, the prototype CDT system, and helical CT, respectively, showing 4.49 times higher than conventional radiography and 4.83 times lower than a CT exam, respectively. CONCLUSIONS: The current work describes the development and performance assessment of both hardware and software for tomosynthesis applications. The authors observed reasonable outcomes by showing a potential for low-dose application in CDT imaging using GPU acceleration.


Asunto(s)
Mama/diagnóstico por imagen , Gráficos por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Radiografía Torácica/métodos , Diseño de Equipo , Humanos , Fantasmas de Imagen , Intensificación de Imagen Radiográfica/instrumentación , Radiografía Torácica/instrumentación , Relación Señal-Ruido
15.
Clin Toxicol (Phila) ; 56(1): 30-36, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28812383

RESUMEN

OBJECTIVES: Whether coronary artery changes are a main mechanism in the development of carbon monoxide (CO)-induced cardiomyopathy remains unknown. We investigated the effects of coronary artery stenosis on the presence or patterns of cardiomyopathy in CO-poisoned patients with myocardial injury defined as elevation of troponin I. MATERIALS AND METHODS: This prospective observational study collected data from consecutive patients who were diagnosed with CO poisoning and myocardial injury during the 24-month study period. Transthoracic echocardiography (TTE) and coronary computed tomography angiography (CCTA) were performed to evaluate cardiac function and coronary artery status. RESULTS: TTE and CCTA were performed in 32 consecutive patients. The observed echocardiographic patterns included non-cardiomyopathy (59.4%), left ventricular global dysfunction (25%), Takotsubo cardiomyopathy (6.3%), and cardiomyopathy matching the distribution of the left anterior descending (LAD) artery (9.4%). Four patients had more than moderate stenosis, while stenoses of the LAD, left circumflex, and right coronary arteries were observed in two (6.3%), three (9.4%), and zero patients, respectively. Patients with coronary artery stenosis did not develop cardiomyopathy except for one patient; this patient also did not have regional wall motion abnormalities (RWMA) matched with the stenosis territory. CONCLUSIONS: Because there was no difference in coronary artery stenosis according to the presence or patterns of CO-induced cardiomyopathy, coronary artery stenosis is not the main mechanism for the development of CO-induced cardiomyopathy. Thus, the evaluation of coronary arteries is not necessary in all patients with CO-induced cardiomyopathy unless there is RWMA consistent with ischemic changes in electrocardiograms and elevated troponin I levels.


Asunto(s)
Intoxicación por Monóxido de Carbono/complicaciones , Cardiomiopatías/etiología , Angiografía por Tomografía Computarizada/métodos , Vasos Coronarios/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Cardiomiopatías/diagnóstico por imagen , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
16.
Contemp Clin Trials Commun ; 9: 60-63, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29696225

RESUMEN

BACKGROUND AND PURPOSE: An optimal pulmonary localization technique for video-assisted thoracic surgery (VATS) of small lung nodules has not yet been established. The LOcalization of Ground-glass-opacity and pulmonary lesions for mInimal Surgery (LOGIS) registry aims to establish a multicenter database and investigate the usefulness and safety of localization techniques for small pulmonary lesions in individuals undergoing VATS. METHODS/DESIGN: The LOGIS registry is a large-scale, multicenter cohort study, aiming to enroll 825 patients at 10 institutions. Based on the inclusion and exclusion criteria, all study participants with pulmonary lesions indicated for VATS will be screened and enrolled at each site. All study participants will undergo preoperative lesion localization by the hook-wire or lipiodol localization methods according to site-specific methods. Within a few hours of marking, thoracoscopic surgery will be done under general anesthesia by experienced thoracoscopic surgeons. The primary endpoints are the success and complication rates of the two localization techniques. Secondary endpoints include procedure duration, recurrence rate, and all-cause mortality. Study participant enrollment will be completed within 2 years. Procedure success rates and incidence of complications will be analyzed based on computed tomography findings. Procedure duration, recurrence rate, and all-cause mortality will be compared between the two techniques. The study will require 5 years for completion, including 6 months of preparation, 3.5 years for recruitment, and 1 year of follow-up endpoint assessment. DISCUSSION: The LOGIS registry, once complete, will provide objective comparative results regarding the usefulness and safety of the lipiodol and hook-wire localization techniques.

17.
Chest ; 151(2): 316-328, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27717643

RESUMEN

BACKGROUND: An optimal method of preoperative localization for pulmonary nodules has yet to be established. This systematic review and meta-analysis aimed to compare the success and complication rates associated with three pulmonary nodule localization methods for video-assisted thoracoscopic surgery (VATS): hook-wire localization, microcoil localization, and lipiodol localization. METHODS: We searched the PubMed, MEDLINE, and EMBASE databases for prospective or retrospective English language studies of VATS localization in adult patients. A noncomparative, random effects model-based meta-analysis was performed to obtain pooled success and complication rates for the three localization methods. RESULTS: A total of 46 clinical studies were enrolled, including 30, 9, and 7 studies of hook-wire, microcoil, and lipiodol localization, respectively. The successful targeting rates for hook-wire, microcoil, and lipiodol localization were 0.98 (95% CI, 0.97-0.99), 0.98 (95% CI, 0.96-0.99), and 0.99 (95% CI, 0.98-1.00), respectively, with corresponding successful operative field targeting rates of 0.94 (95% CI, 0.91-0.96), 0.97 (95% CI, 0.95-0.98), and 0.99 (95% CI, 0.98-1.00), respectively. In addition, the successful VATS rates with hook-wire, microcoil, and lipiodol localization were 0.96 (95% CI, 0.94-0.97), 0.97 (95% CI, 0.94-0.99), and 0.99 (95% CI, 0.98-1.00), respectively. Regarding complications, hook-wire, microcoil, and lipiodol localization were associated with pneumothorax rates of 0.35 (95% CI, 0.28-0.43), 0.16 (95% CI, 0.07-0.34), and 0.31 (95% CI, 0.20-0.46), respectively and hemorrhage rates of 0.16 (95% CI, 0.11-0.23), 0.06 (95% CI, 0.03-0.11), and 0.12 (95% CI, 0.05-0.23), respectively. CONCLUSIONS: All three localization methods yielded similarly highly successful targeting rates. However, hook-wire localization had a relatively lower successful operative field targeting rate because of dislodgement or migration. Lipiodol localization had the highest overall success rate, and microcoil localization yielded the lowest complication rates.


Asunto(s)
Nódulo Pulmonar Solitario/cirugía , Cirugía Torácica Asistida por Video/métodos , Medios de Contraste , Aceite Etiodizado , Humanos , Neumotórax/epidemiología , Complicaciones Posoperatorias/epidemiología , Hemorragia Posoperatoria/epidemiología , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/patología , Cirugía Asistida por Computador , Instrumentos Quirúrgicos , Tomografía Computarizada por Rayos X
19.
Yonsei Med J ; 47(3): 377-83, 2006 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-16807988

RESUMEN

The effectiveness of percutaneous embolotherapy in cases of hemoptysis due to pulmonary tuberculosis from increasing severity of lung parenchymal injury was compared. The pattern of pleural involvement, as seen on chest radiography and angiography, were comparatively analyzed in 230 patients who were available for follow-ups from March 1992 to December 2003. Chest radiography findings were classified into 4 types based on levels of complicated lesions and pleural involvement. Angiography findings were divided into 4 groups based on the level of blood supply to lesions. Early hemostasis with respect to radiographic group were as follows: Type I- 92% (73/79), Type II- 80% (52/65), Type III- 70% (42/60), and Type IV- 56% (52/92); there was an average success rate of 73% (219/296), and continued hemostasis was found in 80% of Type I patients (62/77), 77% of Type II patients (41/53), 62% of Type III patients (25/40), and 45% of Type IV patients (27/60), with an average long- term hemostatic rate of 67% (155/230). Increasing severity of pleural involvement and associated complications correlated with increasing development of systemic collateral arteries other than the bronchial artery. The severely increased circulation in systemic collateral arteries makes it difficult to predict good hemostatic results following embolization. Therefore, we recommend aggressive treatment, such as surgical intervention, after embolization in such instances.


Asunto(s)
Embolización Terapéutica , Hemoptisis/microbiología , Hemoptisis/terapia , Tuberculosis Pulmonar/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Femenino , Estudios de Seguimiento , Hemoptisis/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Tuberculosis Pulmonar/diagnóstico por imagen
20.
JACC Cardiovasc Interv ; 9(8): 793-801, 2016 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-27017370

RESUMEN

OBJECTIVES: The aim of this study was to investigate the predictive accuracy of invasive coronary microvascular indexes for identifying microvascular obstruction (MVO) on cardiac magnetic resonance imaging (CMR) in patients treated with primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). BACKGROUND: We hypothesized that a combination of the index of microcirculatory resistance (IMR) and the thermodilution-derived coronary flow reserve (CFRthermo) will enhance the predictive accuracy of detecting MVO compared with either index alone. METHODS: The IMR and CFRthermo were measured using a single pressure sensor/thermistor-tipped guidewire in 40 STEMI patients immediately after PCI and related to MVO assessed by CMR day 7. The primary endpoint was the predictive accuracy of the IMR for detecting MVO. RESULTS: Patients with an IMR >36 (upper tertile) had a higher rate of MVO compared with those with an IMR ≤36 (93% vs. 39%; p = 0.001). MVO occurred in all patients with an IMR >36 and a CFRthermo ≤1.7 and in no patients with an IMR ≤36 and a CFRthermo >1.7. The IMR remained an independent predictor of MVO (odds ratio: 1.212, 95% confidence interval [CI]: 1.004 to 1.464; p = 0.045) after adjustment for age, creatine kinase-myocardial band, myocardial blush grade, thrombus burden, and CFRthermo. Both the IMR (area under the curve, 0.868, 95% CI: 0.719 to 0.956; p = 0.001) and the CFRthermo (area under the curve, 0.706, 95% CI: 0.536 to 0.842; p = 0.03) were predictive of MVO. Combined IMR and CFRthermo increased the area under the curve for MVO to 0.941. CONCLUSIONS: In patients who underwent primary PCI for STEMI, an increased IMR has an independent predictive value for MVO detection, and combined high IMR and low CFRthermo are highly predictive of MVO. These indexes could be used to further risk-stratify patients and guide regional and systemic therapies.


Asunto(s)
Cateterismo Cardíaco , Circulación Coronaria , Vasos Coronarios/diagnóstico por imagen , Imagen por Resonancia Magnética , Microcirculación , Intervención Coronaria Percutánea/efectos adversos , Infarto del Miocardio con Elevación del ST/terapia , Termodilución , Resistencia Vascular , Anciano , Área Bajo la Curva , Distribución de Chi-Cuadrado , Vasos Coronarios/fisiopatología , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Curva ROC , Reproducibilidad de los Resultados , Factores de Riesgo , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/fisiopatología , Resultado del Tratamiento
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