1.Validation of Deep-Learning Image Reconstruction for Low-Dose Chest Computed Tomography Scan: Emphasis on Image Quality and Noise
Joo Hee KIM ; Hyun Jung YOON ; Eunju LEE ; Injoong KIM ; Yoon Ki CHA ; So Hyeon BAK
Korean Journal of Radiology 2021;22(1):131-138
Objective:
Iterative reconstruction degrades image quality. Thus, further advances in image reconstruction are necessary to overcome some limitations of this technique in low-dose computed tomography (LDCT) scan of the chest. Deep-learning image reconstruction (DLIR) is a new method used to reduce dose while maintaining image quality. The purposes of this study was to evaluate image quality and noise of LDCT scan images reconstructed with DLIR and compare with those of images reconstructed with the adaptive statistical iterative reconstruction-Veo at a level of 30% (ASiR-V 30%).
Materials and Methods:
This retrospective study included 58 patients who underwent LDCT scan for lung cancer screening.Datasets were reconstructed with ASiR-V 30% and DLIR at medium and high levels (DLIR-M and DLIR-H, respectively). The objective image signal and noise, which represented mean attenuation value and standard deviation in Hounsfield units for the lungs, mediastinum, liver, and background air, and subjective image contrast, image noise, and conspicuity of structures were evaluated. The differences between CT scan images subjected to ASiR-V 30%, DLIR-M, and DLIR-H were evaluated.
Results:
Based on the objective analysis, the image signals did not significantly differ among ASiR-V 30%, DLIR-M, and DLIR-H (p = 0.949, 0.737, 0.366, and 0.358 in the lungs, mediastinum, liver, and background air, respectively). However, the noise was significantly lower in DLIR-M and DLIR-H than in ASiR-V 30% (all p < 0.001). DLIR had higher signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) than ASiR-V 30% (p = 0.027, < 0.001, and < 0.001 in the SNR of the lungs, mediastinum, and liver, respectively; all p < 0.001 in the CNR). According to the subjective analysis, DLIR had higher image contrast and lower image noise than ASiR-V 30% (all p < 0.001). DLIR was superior to ASiR-V 30% in identifying the pulmonary arteries and veins, trachea and bronchi, lymph nodes, and pleura and pericardium (all p < 0.001).
Conclusion
DLIR significantly reduced the image noise in chest LDCT scan images compared with ASiR-V 30% while maintaining superior image quality.
2.Efficacy of bivalent vaccines of porcine circovirus type 2 and Mycoplasma hyopneumoniaein specific pathogen-free pigs challenged with porcine circovirus type 2d
Jeonggyo LIM ; Myongha JIN ; Injoong YOON ; Han Sang YOO
Journal of Veterinary Science 2022;23(3):e49-
Background:
Porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (MHP) are economically significant pathogens in the pig industry. The use of combined vaccines against PCV2 and MHP is one of the most effective ways of protecting pigs from both diseases, and it has become a part of general management.
Objectives:
This study evaluated the efficacy of two new bivalent vaccines of PCV2 and MHP (Myco-X and Myco-XD) in SPF pigs. Myco-X and Myco-XD are a combined vaccine of MHP with PCV2b and PCV2d, respectively.
Methods:
Sixteen pigs were divided into four groups: Myco-X-vaccinated challenged, Myco-XD-vaccinated challenged, unvaccinated challenged, and unvaccinated unchallenged.Two milliliters of Myco-X were administered intramuscularly, and 0.5 mL of Myco-XD was injected intradermally at 3 wk of age. The pigs were challenged with virulent PCV2d via the intramuscular and intranasal route 4 wk post-vaccination.
Results:
All vaccinated pigs showed effective reduction of the clinical signs, the PCV2d load in the blood and nasal swab samples, as well as lung and lymphoid tissue lesions in the challenge test. Compared to unvaccinated challenged animals, the vaccinated challenged animals showed significantly higher (p < 0.05) levels of anti-PCV2 IgG, PCV2d-specific interferon-γ (IFN-γ), and anti-MHP IgG.
Conclusions
Based on clinical, microbiological, serological, and pathological assessments, this study confirmed that both combined vaccines could protect pigs against PCV2 infection caused by PCV2d. On the other hand, further research on the efficacy evaluation of these new vaccines against the MHP challenge and PCV2d/MHP co-challenge is needed.
3.Diagnostic Role of Conventional Ultrasonography and Shearwave Elastography in Asymptomatic Patients with Diffuse Thyroid Disease: Initial Experience with 57 Patients.
Injoong KIM ; Eun Kyung KIM ; Jung Hyun YOON ; Kyung Hwa HAN ; Eun Ju SON ; Hee Jung MOON ; Jin Young KWAK
Yonsei Medical Journal 2014;55(1):247-253
PURPOSE: Thyroid ultrasonography (US) is a useful diagnostic tool in the evaluation of diffuse thyroid disease (DTD), whereas shearwave elastography is a dynamic technique that can provide information about tissue hardness by using acoustic shearwaves remotely induced by a focused ultrasonic beam. This study aims at investigating the role of conventional US and shearwave elastography in the diagnosis of asymptomatic patients with DTD. MATERIALS AND METHODS: Fifty-seven patients who underwent both conventional US and shearwave elastography were included in this study. Interobserver variability of the three radiologists in assessment of underlying thyroid echogenicity on conventional US was analyzed. Diagnostic performances for diagnosing DTD on conventional US and shearwave elastography were calculated and compared. RESULTS: Fair agreement was observed in the identification of DTD with conventional US (kappa value=0.27). The area under the receiver operating characteristic curve (Az) were 0.52-0.585 on conventional US by three radiologists. The Az values when using the mean and maximum elasticity values as a diagnostic criteria for DTD were 0.619 and 0.59 on shearwave elastography. Patients with DTD showed higher mean [24.1+/-10 kilo-Pascals (kPa)] and maximum (36.4+/-13.3 kPa) elasticity values on shearwave elastography when compared to the normal group (23.4+/-10.8 kPa and 33.7+/-12.4 kPa, respectively), although without statistical significance (p=0.802 and p=0.452, respectively). CONCLUSION: Conventional US did not show reliable interobserver agreement in the diagnosis of DTD. Although not statistically significant, shearwave elastography may provide additional information in the diagnosis of DTD. Therefore, larger prospective studies are needed to define the values of shearwave elastography for diagnosing DTD.
Adult
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Elasticity Imaging Techniques/*methods
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Female
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Humans
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Male
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Middle Aged
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Prospective Studies
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Thyroid Diseases/*ultrasonography
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Thyroid Gland/*ultrasonography
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Ultrasonography/*methods
4.Development of Actinobacillus pleuropneumoniae ApxI, ApxII, and ApxIII-specific ELISA methods for evaluation of vaccine efficiency
Myunghwan JUNG ; Hokeun WON ; Min Kyoung SHIN ; Myung Whan OH ; Soojin SHIM ; Injoong YOON ; Han Sang YOO
Journal of Veterinary Science 2019;20(2):e2-
Among various vaccines against Actinobacillus pleuropneumoniae, subunit vaccines using recombinant proteins of ApxI, ApxII, and ApxIII as vaccine antigens have shown good efficacy in terms of safety and protection. Therefore, subunit vaccines are being applied worldwide and the development of new subunit vaccines is actively being conducted. To evaluate the efficacy of the subunit vaccines, it is important to measure immune responses to each Apx toxin separately. However, the cross-reactivity of antibodies makes it difficult to measure specific immune reactivity to each toxin. In the present study, specific antigen regions among the toxins were identified and cloned to solve this problem. The antigenicity of each recombinant protein was demonstrated by Western blot. Using the recombinant proteins, we developed enzyme-linked immunosorbent assay (ELISA) methods that can detect specific immune responses to each Apx toxin in laboratory guinea pigs. We suggest that the ELISA method developed in this study can be an important tool in the evaluation of vaccine efficiency and vaccine development.
Actinobacillus pleuropneumoniae
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Actinobacillus
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Animals
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Antibodies
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Blotting, Western
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Clone Cells
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Enzyme-Linked Immunosorbent Assay
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Guinea Pigs
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Methods
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Recombinant Proteins
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Vaccines
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Vaccines, Subunit