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1.
J Infect Chemother ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34863647

RESUMO

INTRODUCTION: Monoclonal antibody therapy has been reported to be highly effective for preventing hospitalisation and severe cases in patients with Coronavirus Disease 2019 (COVID-19). However, since the drug is not readily available, it is important to rapidly and appropriately identify high-risk patients who can benefit most from therapy. Therefore, we designed a risk scoring system to identify at-risk COVID-19 patients in our region during the largest surge of COVID-19, from July to September 2021. METHODS: According to the risk scores, confirmed COVID-19 patients were introduced to receive REGN-CoV-2 to our hospital by regional health centre from 18th August (Term 3). The primary outcome was the comparison of the number of hospitalisation and severe condition with other periods, the 4th wave (Term 1) and the early part of the 5th wave (Term 2) in Japan. RESULTS: During Term 3, 115 patients were stratified with the scoring system and administered REGN-COV-2. The number of hospitalisation vs severe cases were 60 (5.2%) vs 14 (1.2%), 8 (1.5%) vs 3 (0.6%) and 21 (1.2%) vs 2 (0.1%), in term 1, 2 and 3, respectively. Among those aged <60 years, compared with term 1, the relative risk of hospitalisation and severe condition were 0.25 (95% CI: 0.12-0.53) and 0.10 (95% CI: 0.01-0.80), respectively, in term 3. Drug adverse events were fever (3: 2.6%), headache (1: 0.9%) and neck rash (1: 0.9%), all events were resolved within 24 h wth no serious adverse event. CONCLUSIONS: The administration of monoclonal antibody therapy using a risk scoring system significantly reduced the number of hospitalisation and disease severity of COVID-19 without any serious adverse events and avoided regional medical collapse.

2.
Diagnostics (Basel) ; 11(12)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34943507

RESUMO

The occurrence of interstitial lung disease (ILD) with peripheral pulmonary lesions (PPLs) is closely linked to the development of lung cancer. Yet, the best diagnostic approach for identifying PPLs in patients with ILD remains elusive. This study retrospectively investigated the application of transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS) to the effective and safe diagnosis of PPLs when compared with conventional TBB. The study sample included a consecutive series of 19 patients with ILD who underwent conventional TBB or TBB using EBUS-GS at Tosei General Hospital between 1 April 2013 and 31 October 2015. The two techniques were compared based on diagnostic yield and associated complications. The diagnostic yield of EBUS-GS TBB was significantly higher than that of conventional TBB (p = 0.009), especially for small lesions (≤20 mm), lesions located in the lower lobes, lesions with a positive bronchus sign, and lesions visible by chest radiography (p = 0.010, p = 0.022, p = 0.006, and p = 0.002, respectively). There were no significant differences in complication rates. Therefore, EBUS-GS is an effective alternative for the diagnosis of PPLs in patients with ILD, without additional complications.

3.
Cancers (Basel) ; 13(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34830905

RESUMO

In patients with interstitial lung disease (ILD), the most frequent locations of lung cancer are within or near fibrotic lesions. However, the diagnostic yield for peripheral pulmonary lesions (PPLs) within or near fibrotic lesions using endobronchial ultrasonography with a guide sheath transbronchial biopsy (EBUS-GS TBB) may be unsatisfactory compared to that for PPLs distant from fibrotic lesions because of the difficulty in reaching the lesions. Our objectives were to evaluate the yield for PPLs using EBUS-GS TBB according to the proximity of PPLs to fibrotic lesions and to determine factors affecting the yield for PPLs. We retrospectively investigated 323 consecutive lesions using EBUS-GS TBB between 1 November 2014 and 31 December 2016. We identified PPLs with ILD in such lesions. PPLs with ILD were divided into PPLs within or near fibrotic lesions which met the criterion of PPLs, and of fibrotic lesions overlapping each other (PPLs-FL) and those distant from fibrotic lesions, which met the criterion of PPLs and the area of fibrotic lesion not overlapping each other (PPLs-NFL). Of the 323 lesions, 55 were included (31 PPLs-FL and 24 PPLs-NFL). The diagnostic yield for PPLs-FL was significantly lower than for PPLs-NFL (45.2% vs. 83.3%, p = 0.004). Multivariate analysis revealed that PPLs-NFL (odds ratio (OR) = 7.509) and a probe position within the lesion (OR = 4.172) were significant factors affecting diagnostic yield. Lesion's positional relation to fibrotic lesions and the probe position were important factors affecting the successful diagnosis via EBUS-GS TBB in these patients.

4.
J Hazard Mater ; : 127847, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34836686

RESUMO

Retinoic acid receptors (RARs) control reproduction and development in vertebrates, but little attention has been paid to anthropogenic chemicals exhibiting RAR agoniztic/antagonistic activity. Here we applied a His-RARα pull-down assay combined with high-resolution mass spectrometry to identify chemicals with RARα activity in house dust. After screening, a total of 540 peaks were retained as potential RARα ligands. The mass spectra of 14 chemicals matched with those in the database, of which triphenyl phosphate, galaxolidone, di(2-ethylhexyl) phthalate (DEHP), tris(2-ethylhexyl) phosphate (TEHP), and tris(2-butoxyethyl) phosphate were confirmed by their standards. While one chemical in the sample matched with monophenyl phosphate in the MS/MS database, its retention time was much higher than that of monophenyl phosphate standard, suggesting that it may be an in-source fragment. Its parent ion was finally identified to be m/z 399.2663 using a similarity analysis among chromatographic peaks of hundreds of ions at the same retention time in MS1 spectrum, and bis(2-ethylhexyl) phenyl phosphate (BEHPP) was identified. BEHPP, DEHP, and TEHP were for the first time identified to be RARα antagonists with IC50 values of 6556, 6600, and 2538 nM, respectively. This study improved structural annotation and filled the knowledge gap regarding widespread environmental contaminants with RAR antagonistic activity.

5.
Jpn J Clin Oncol ; 51(12): 1729-1735, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34625805

RESUMO

BACKGROUND: The use of volumetric modulated arc therapy is gradually widespread for locally advanced non-small cell lung cancer. The purpose of this study was to identify the factors that caused ≥ grade 2 radiation pneumonitis and evaluate the impact of using volumetric modulated arc therapy on the incidence of ≥ grade 2 radiation pneumonitis by comparing three-dimensional conformal radiation therapy. METHODS: We retrospectively evaluated 124 patients who underwent radical radiotherapy for locally advanced non-small cell lung cancer in our institution between 2008 and 2019. The following variables were analysed to detect the factors that affected ≥ grade 2 radiation pneumonitis; age, sex, the presence of interstitial lung disease, pulmonary emphysema, tumour location, stage, PTV/lung volume, lung V20Gy, total dose, concurrent chemoradiotherapy, adjuvant immune checkpoint inhibitor, radiotherapy method. Radiation pneumonitis was evaluated using the common terminology criteria for adverse events (version 5.0). RESULTS: A total of 84 patients underwent three-dimensional conformal radiation therapy (3D-CRT group) and 40 patients underwent volumetric modulated arc therapy (VMAT group). The cumulative incidence of ≥ grade 2 radiation pneumonitis at 12 months was significantly lower in the VMAT group than in the 3D-CRT group (25% vs. 49.1%). The use of volumetric modulated arc therapy was a significant factor for ≥ grade 2 radiation pneumonitis (HR:0.32, 95% CI: 0.15-0.65, P = 0.0017) in addition to lung V20Gy (≥ 24%, HR:5.72 (95% CI: 2.87-11.4), P < 0.0001) and total dose (≥ 70 Gy, HR:2.64 (95% CI: 1.39-5.03), P = 0.0031) even after adjustment by multivariate analysis. CONCLUSIONS: We identified factors associated with ≥ grade 2 radiation pneumonitis in radiotherapy for patients with locally advanced non-small cell lung cancer. Volumetric modulated arc therapy has potential benefits to reduce the risk of ≥ grade 2 radiation pneumonitis.

6.
Respirol Case Rep ; 9(11): e0865, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34707877

RESUMO

Diffuse alveolar damage (DAD) is known to be a pathological hallmark of acute respiratory distress syndrome or acute interstitial pneumonia, and to have a poor prognosis. We report a case of anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive clinically amyopathic dermatomyositis (CADM) with rapidly progressive interstitial lung disease (RP-ILD), in which DAD was confirmed by transbronchial lung cryobiopsy at an early stage without respiratory failure. Although this patient initially did not show respiratory failure, his respiratory condition gradually worsened despite intensive immunosuppression therapy and he died 3 months later. Therefore, the early pathological findings of DAD did not match the clinical picture, which showed no respiratory failure. However, these findings were consistent with the subsequent course and poor outcome. Histological DAD, even in the absence of respiratory failure, may indicate a subsequent poor prognosis and explain the refractory course of RP-ILD with anti-MDA5 antibody-positive CADM.

7.
Respir Investig ; 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34548272

RESUMO

BACKGROUND: The COPD Assessment Test (CAT) has been studied as a measure of health status in idiopathic pulmonary fibrosis (IPF) and interstitial lung disease associated with connective tissue disease. However, its prognostic value is unknown. The present study explored the association between CAT score and mortality in fibrotic interstitial lung disease (FILD), including IPF and other forms of ILD. METHODS: We retrospectively analyzed 501 consecutive patients with FILD who underwent clinical assessment, including pulmonary function test and CAT. The association between CAT score and 3-year mortality was assessed using Cox proportional hazard analysis, Kaplan-Meier plots, and the log-rank test for trend. To handle missing data, the imputed method was used. RESULTS: The patients' median age was 68 years, and 320 were male (63.9%). Regarding CAT severity, 203 patients had a low impact level (score <10), 195 had a medium level (10-20), 80 had a high level (21-30), and 23 had a very high level (31-40). During the 3-year study period, 118 patients died. After adjusting for age, sex, forced vital capacity, diffusion capacity for carbon monoxide, IPF diagnosis, and usual interstitial pneumonia pattern on high-resolution computed tomography, the CAT score was significantly associated with 3-year mortality (hazard ratio in increments of 10 points: 1.458, 95% confidence interval 1.161-1.830; p < 0.001). In addition, patients with high and very high impact levels had twofold and threefold higher mortality risk than those with low levels, respectively. CONCLUSION: The CAT has prognostic value in FILD.

8.
Respir Investig ; 59(6): 849-858, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34561207

RESUMO

BACKGROUND: The beneficial effects of pulmonary rehabilitation (PR) for patients with idiopathic pleuroparenchymal fibroelastosis (IPPFE) remain unknown. This study aimed to examine the efficacy, feasibility, and safety of PR for IPPFE. METHODS: We retrospectively investigated 25 patients with IPPFE referred for PR between April 2007 and March 2017. The PR mainly consisted of a 10-week exercise training program. The primary outcome was a change in 6-min walk distance (6MWD). Secondary outcomes included changes in dyspnea (transition dyspnea index [TDI]), anxiety and depression (hospital anxiety and depression scale [HADS]), and health-related quality of life (HRQoL) (St George's respiratory questionnaire [SGRQ]). RESULTS: Thirteen patients participated in the PR program (PRP). Recurrent pneumothorax was the most common reason for patients not participating in the PRP. Four patients discontinued the PRP due to the recurrence of pneumothorax, new onset of pneumomediastinum, stroke, and another reason, respectively. Nine patients completed the PRP. Significant improvement was observed in 6MWD (median [interquartile range], 90 m [55-116 m]; P = 0.033). Clinically important improvements in the 6MWD, and TDI, HADS-anxiety, HADS-depression, and SGRQ total domain scores were observed in seven (78%), five (56%), four (44%), four (44%), and five (56%) of the nine patients, respectively. CONCLUSIONS: Patients with IPPFE benefited from PR in terms of exercise capacity, dyspnea, anxiety, depression, and HRQoL. Pneumothorax and pneumomediastinum may impede the implementation of a PRP for patients with IPPFE. While careful patient selection is required, PR may be an efficacious non-pharmacological approach for managing disabilities in patients with IPPFE.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Dispneia/etiologia , Tolerância ao Exercício , Estudos de Viabilidade , Humanos , Estudos Retrospectivos
9.
Sci Rep ; 11(1): 16232, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376721

RESUMO

To predict grade ≥ 2 radiation pneumonitis (RP) in patients with locally advanced non-small cell lung cancer (NSCLC) using multi-region radiomics analysis. Data from 77 patients with NSCLC who underwent definitive radiotherapy between 2008 and 2018 were analyzed. Radiomic feature extraction from the whole lung (whole-lung radiomics analysis) and imaging- and dosimetric-based segmentation (multi-region radiomics analysis) were performed. Patients with RP grade ≥ 2 or < 2 were classified. Predictors were selected with least absolute shrinkage and selection operator logistic regression and the model was built with neural network classifiers. A total of 49,383 radiomics features per patient image were extracted from the radiotherapy planning computed tomography. We identified 4 features and 13 radiomics features in the whole-lung and multi-region radiomics analysis for classification, respectively. The accuracy and area under the curve (AUC) without the synthetic minority over-sampling technique (SMOTE) were 60.8%, and 0.62 for whole-lung and 80.1%, and 0.84 for multi-region radiomics analysis. These were improved 1.7% for whole-lung and 2.1% for multi-region radiomics analysis with the SMOTE. The developed multi-region radiomics analysis can help predict grade ≥ 2 RP. The radiomics features in the median- and high-dose regions, and the local intensity roughness and variation were important factors in predicting grade ≥ 2 RP.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/diagnóstico , Radiometria/métodos , Radioterapia/efeitos adversos , Área Sob a Curva , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/patologia , Pneumonite por Radiação/etiologia
10.
Respiration ; 100(12): 1151-1157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34247176

RESUMO

BACKGROUND: Although physical activity is associated with mortality in patients with idiopathic pulmonary fibrosis (IPF), reference values to interpret levels of physical activity are lacking. OBJECTIVES: This study aimed to investigate the prognostic significance of physical activity assessed by step count and its cutoff points for all-cause mortality. METHODS: We measured physical activity (steps per day) using an accelerometer in patients with IPF at the time of diagnosis. Relationships among physical activity and mortality, as well as cutoff points of daily step count to predict all-cause mortality were examined. RESULTS: Eighty-seven patients (73 males) were enrolled. Forty-four patients (50.1%) died during the follow-up (median 54 months). In analysis adjusting for Gender-Age-Physiology stage and 6-min walk distance, daily step count was an independent predictor of all-cause mortality (hazard ratio (HR) = 0.820, 95% confidence interval (CI) = 0.694-0.968, p = 0.019). The optimal cutoff point (receiving operating characteristic analysis) for 1-year mortality was 3,473 steps per day (sensitivity = 0.818 and specificity = 0.724). Mortality was significantly lower in patients with a daily step count exceeding 3,473 steps than in those whose count was 3,473 or less (HR = 0.395, 95% CI = 0.218-0.715, p = 0.002). CONCLUSIONS: Step count, an easily interpretable measurement, was a significant predictor of all-cause mortality in patients with IPF. At the time of diagnosis, a count that exceeded the cutoff point of 3,473 steps/day more than halved mortality. These findings highlight the importance of assessing physical activity in this patient population.

11.
Sci Rep ; 11(1): 14370, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257319

RESUMO

University administrators and mental health clinicians have raised concerns about depression and anxiety among Ph.D. students, yet no study has systematically synthesized the available evidence in this area. After searching the literature for studies reporting on depression, anxiety, and/or suicidal ideation among Ph.D. students, we included 32 articles. Among 16 studies reporting the prevalence of clinically significant symptoms of depression across 23,469 Ph.D. students, the pooled estimate of the proportion of students with depression was 0.24 (95% confidence interval [CI], 0.18-0.31; I2 = 98.75%). In a meta-analysis of the nine studies reporting the prevalence of clinically significant symptoms of anxiety across 15,626 students, the estimated proportion of students with anxiety was 0.17 (95% CI, 0.12-0.23; I2 = 98.05%). We conclude that depression and anxiety are highly prevalent among Ph.D. students. Data limitations precluded our ability to obtain a pooled estimate of suicidal ideation prevalence. Programs that systematically monitor and promote the mental health of Ph.D. students are urgently needed.

12.
Liver Cancer ; 10(2): 151-160, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33977091

RESUMO

Background: Overall survival of patients with advanced hepatocellular carcinoma (HCC) with Vp4 (tumor thrombosis of the main trunk or bilobar of the portal vein) is extremely poor. Purpose: The purpose of this study is to clarify the prognosis of hepatic arterial infusion chemotherapy (HAIC) combined with radiation therapy (RT) for advanced HCC with Vp4 and to analyze the factors that contribute to the prognosis. Methods: In this retrospective cohort study, 51 HCC patients who were treated with HAIC and RT for portal vein tumor thrombosis and met the following criteria were enrolled: (i) with Vp4; (ii) Child-Pugh score of 5-7; (iii) Eastern Cooperative Oncology Group performance status of 0 or 1; (iv) no history of systemic therapy; and (v) from September 2004 to April 2019. Results: Median overall survival and median progression-free survival were 12.1 and 4.2 months, respectively. Multivariate analysis showed >50% of relative tumor volume in the liver (HR, 3.027; p = 0.008) and extrahepatic spread with (HR, 3.773; p = 0.040) as significant and independent factors of OS. The total overall response rate (ORR) was 19.6%; ORR in main tumor was 13.7%; and ORR in Vp4 was 51.0%. None of the patients who received HAIC combined with RT for advanced HCC with Vp4 developed hepatic failure. This combination therapy of HAIC with RT was safe and well tolerated in all cases. Conclusion: Combination therapies of HAIC and RT might be good therapy for advanced HCC with Vp4.

13.
Int J Radiat Oncol Biol Phys ; 110(2): 616-617, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33989585
15.
Med Phys ; 48(6): 3200-3207, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33792065

RESUMO

PURPOSE: To develop a dosimetric internal target volume (ITV) margin (DIM) for respiratory motion in lung stereotactic body radiotherapy (SBRT) and to evaluate DIM with a nonuniform volume prescription (NVP) and the point prescription (PP). METHODS: Volumetric modulated arc therapy (VMAT) treatment plans with PP and NVP were created on a heterogeneous programmable respiratory motion phantom, with a tumor (30-mm diameter) inside a cylindrical lung insert. The tumor was defined as the gross tumor volume (GTV), equal to the clinical target volume (CTV). Five-millimeter and 0-mm margins were used for the ITV and setup margins, respectively. The phantom was moved in cranio-caudal direction with a biquadratic sinusoidal waveform with a 4-s cycle and an amplitude of ±5-10 mm. The interplay effect was evaluated by measuring the dose profile with a film in the sagittal plane for different respiratory periods and different initial respiratory phases. DIM was based on the respiratory motion amplitude that satisfied 100% and 95% coverage of the prescribed dose by the minimum dose of the CTV. Moreover, the absolute dose was measured with and without respiratory motion for NVP by a pinpoint chamber. RESULTS: The dose difference in the tumor region due to the interplay effect was within 1.0%. The gamma passing rate was over 95.1% for different respiratory periods and 98.6% for different initial respiratory phases. DIM with PP was almost equivalent to the margin of the respiratory motion. However, DIM with NVP was 2.0 and 1.8 times larger than the margin of the respiratory motion for the 100% and 95% coverage of the prescribed doses, respectively. CONCLUSION: The interplay effects experienced between the MLC sequence and tumor motion were negligible for NVP. The DIM analysis revealed that the margin to compensate the respiratory tumor motion could be reduced by more than 44-50% for NVP in SBRT.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Pulmão , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Prescrições , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
16.
J Pharmacol Sci ; 145(4): 335-339, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33712285

RESUMO

We previously reported that brotizolam, but not suvorexant, delayed recovery from isoflurane anesthesia in mice. However, the effects of hypnotics may be altered by the circadian rhythm. Locomotor activity was measured using sighted (ICR and C57BL/6J) and blind (FVB/N and C3H/HeN) mice, and the effects of hypnotics on isoflurane anesthesia were compared during the light and dark periods. In sighted mice, recovery induced by brotizolam was delayed in the light period, while that by suvorexant was delayed in the dark period. In C57BL/6J mice, delayed recovery induced by brotizolam was marked, and that by suvorexant was observed in the light and dark periods. Locomotor activity was low in the last 6 h of the dark period in blind mice, and was similar to that in the light period. In blind mice, delayed recovery induced by brotizolam was identical in both periods, while suvorexant did not influence recovery from isoflurane anesthesia. These results suggest that the effects of hypnotics on isoflurane anesthesia are altered by the circadian rhythm and that daily light-dark stimuli may be required for the chronopharmacological effects of hypnotics.


Assuntos
Período de Recuperação da Anestesia , Anestesia por Inalação , Anestésicos Inalatórios , Hipnóticos e Sedativos/farmacologia , Isoflurano , Fotoperíodo , Animais , Azepinas/farmacologia , Cronofarmacocinética , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia , Isoflurano/farmacologia , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Atividade Motora/efeitos dos fármacos , Fatores de Tempo , Triazóis/farmacologia
19.
Circ J ; 85(4): 333-342, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33536399

RESUMO

BACKGROUND: There is limited evidence for pulmonary arterial hypertension (PAH)-targeted therapy in patients with pulmonary hypertension associated with respiratory disease (R-PH). Therefore, we conducted a multicenter prospective study of patients with R-PH to examine real-world characteristics of responders by evaluating demographics, treatment backgrounds, and prognosis.Methods and Results:Among the 281 patients with R-PH included in this study, there was a treatment-naïve cohort of 183 patients with normal pulmonary arterial wedge pressure and 1 of 4 major diseases (chronic obstructive pulmonary diseases, interstitial pneumonia [IP], IP with connective tissue disease, or combined pulmonary fibrosis with emphysema); 43% of patients had mild ventilatory impairment (MVI), whereas 52% had a severe form of PH. 68% received PAH-targeted therapies (mainly phosphodiesterase-5 inhibitors). Among patients with MVI, those treated initially (i.e., within 2 months of the first right heart catheterization) had better survival than patients not treated initially (3-year survival 70.6% vs. 34.2%; P=0.01); there was no significant difference in survival in the group with severe ventilatory impairment (49.6% vs. 32.1%; P=0.38). Responders to PAH-targeted therapy were more prevalent in the group with MVI. CONCLUSIONS: This first Japanese registry of R-PH showed that a high proportion of patients with MVI (PAH phenotype) had better survival if they received initial treatment with PAH-targeted therapies. Responders were predominant in the group with MVI.

20.
J Appl Clin Med Phys ; 22(4): 184-192, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33599386

RESUMO

PURPOSE: To synthesize a dual-energy computed tomography (DECT) image from an equivalent kilovoltage computed tomography (kV-CT) image using a deep convolutional adversarial network. METHODS: A total of 18,084 images of 28 patients are categorized into training and test datasets. Monoenergetic CT images at 40, 70, and 140 keV and equivalent kV-CT images at 120 kVp are reconstructed via DECT and are defined as the reference images. An image prediction framework is created to generate monoenergetic computed tomography (CT) images from kV-CT images. The accuracy of the images generated by the CNN model is determined by evaluating the mean absolute error (MAE), mean square error (MSE), relative root mean square error (RMSE), peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and mutual information between the synthesized and reference monochromatic CT images. Moreover, the pixel values between the synthetic and reference images are measured and compared using a manually drawn region of interest (ROI). RESULTS: The difference in the monoenergetic CT numbers of the ROIs between the synthetic and reference monoenergetic CT images is within the standard deviation values. The MAE, MSE, RMSE, and SSIM are the smallest for the image conversion of 120 kVp to 140 keV. The PSNR is the smallest and the MI is the largest for the synthetic 70 keV image. CONCLUSIONS: The proposed model can act as a suitable alternative to the existing methods for the reconstruction of monoenergetic CT images in DECT from single-energy CT images.


Assuntos
Redes Neurais de Computação , Tomografia Computadorizada por Raios X , Humanos , Processamento de Imagem Assistida por Computador , Razão Sinal-Ruído
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