Hoen-oh Shin - Academia.edu (original) (raw)
Papers by Hoen-oh Shin
protocols.io, Jan 8, 2019
Objectives Objectives: To evaluate frequency and severity of complications after CT-guided lung b... more Objectives Objectives: To evaluate frequency and severity of complications after CT-guided lung biopsy using the Society of Interventional Radiology (SIR) classification, and to assess risk factors for overall and major complications. Methods: Methods: 311 consecutive biopsies with a non-coaxial semi-automated 18 gauge biopsy system were retrospectively evaluated. Complications after biopsy were classified into minor SIR1-2 and major SIR3-6. Studied risk factors for complications were patient-related (age, sex and underlying emphysema), lesion-related (size, location, morphologic characteristics, depth from the pleura and histopathology), and technique-related (patient position during procedure, thoracic wall thickness at needle path, procedure time length and number of procedural CT images, number of pleural passes, fissure penetration and needle-to-blood vessel angle). Data were analyzed using logistic and ordinal regression. Results: Results: Complications were pneumothorax and pulmonary hemorrhage. The complications were minor SIR1-2 in 142 patients (45.6%), and major SIR3-4 in 25 patients (8%). SIR5-6 complications were not present. Emphysema, smaller deeply located lesion, increased puncture time length and number of procedural CT images, multiple pleural passes and fissure puncture were significant risk factors for complications severity in univariate analysis. Emphysema (OR=8.8, p<0.001), lesion depth from the pleura (OR=1.9 per cm, p<0.001), and fissure puncture (OR=9.4, p=0.01) were the independent factors for major complications in a multiple logistic regression model. No statistical difference of complications rate between the radiologists performing biopsies was observed. Conclusions: Conclusions: Knowledge about risk factors influencing complications severity is important for planning and performing CT-guided lung biopsies.
Objectives: To analyze the influence of multiplanar reformations of thincollimated multidetector ... more Objectives: To analyze the influence of multiplanar reformations of thincollimated multidetector computed tomography datasets on low-contrast performance. Materials and Methods: A low-contrast phantom simulating focal hypodense lesions (Ϫ20 HU object contrast) was scanned on a 64-slice spiral CT scanner at 4 different dose levels (25 mAs, 50 mAs, 100 mAs, 200 mAs, and no dose modulation). Other scanner parameters were as follows: tube voltage ϭ 120 kVp, rotation time ϭ 0.8 s, reconstructed slice thickness ϭ 0.625 mm, reconstruction interval ϭ 0.5 mm, reconstruction kernel ϭ standard. Coronal reformations were created using the open-source software OsiriX. A sliding-thin-slab (STS) averaging algorithm was applied to each axial and each reformatted dataset with an increasing slab thickness from 1 to 20 slices. The low-contrast performance of all datasets was calculated semiautomatically using a reader-independent, statistical approach and is expressed as the visibility index. The results were analyzed for differences between the coronal reformations and the original axial datasets. In addition, the statistical approach used herein was validated against a reader study. Results: The visibility index of the coronal reformatted datasets over all lesion sizes was inferior when compared with the original axial datasets and reached 75.4% (Ϯ11.7%), 79.9% (Ϯ16.3%), 79.4% (Ϯ5.5%), and 93.7% (Ϯ14.6%) for dose levels of 25, 50, 100, and 200 mAs, respectively. The overall mean low-contrast performance was 82.1% of the axial dataset (P Ͻ 0.05, except for 200 mAs). The deterioration of low-contrast performance was inversely correlated with lesion size (R 2 ϭ 0.91). The use of the STS averaging algorithm significantly improved image quality for all datasets (112.6%-180.2%) with the beneficial effect being stronger for the coronal reformations. There was no statistically significant difference in the evaluation of low-contrast performance between the statistical approach and the ready study. Conclusion: Coronal reformations of thin-collimated multidetector computed tomography datasets show a significant reduction of low-contrast performance when compared with the original axial dataset, especially in high noise data. The use of an STS averaging algorithm had a significant benefit for both, coronal and axial orientations. The effect was more pronounced with coronal reformations and should be routinely applied to improve image quality.
Nephrology Dialysis Transplantation, Jun 5, 2007
Zeitschrift Fur Orthopadie Und Unfallchirurgie, Jan 7, 2013
ABSTRACT
Pneumologie, Feb 23, 2017
Humanmedizin kompakt, Jul 20, 2014
arXiv (Cornell University), Sep 14, 2018
To evaluate the influence of a model-based iterative reconstruction algorithm (ADMIRE) on image t... more To evaluate the influence of a model-based iterative reconstruction algorithm (ADMIRE) on image texture and image visual impression as a supplement to measurements of common image quality parameters such as noise levels and spatial resolution. Methods: An American College of Radiology CT accreditation phantom (ACR phantom) was examined at different radiation dose levels expressed by the volumetric computed tomography dose index (CTDI vol = 0.67, 1.64, 3.31 and 6.65 mGy). To characterize the image texture, two Haralick texture parameters, i.e. contrast and entropy, for different dose level and reconstruction algorithms were assessed. The visual impression of images and their structural differences were evaluated using the structural similarity index (SSIM). Noise defined as the standard deviation of the voxel density was determined for all dose and AMIRE levels and compared to those by filtered back projection. The spatial resolution was determined by the modulation transfer functions and the line spread function. Results: The Haralick texture parameters, contrast and entropy, decreased with increasing ADMIRE levels I up to V. ADMIRE III, IV and V offered a comparable contrast and entropy to those calculated by the filter back projection with a radiation dose reduction up to 50%. On the other hand, SSIM improved with increasing ADMIRE levels. SSIM calculated by ADMIRE IV and V showed similar values by the filter back projection with a CTDI vol decrease up to 50%. Spatial resolution was retained up to 90% dose reduction. With increasing ADMIRE as well as dose level the noise distribution shifted to a more narrow distribution, which was in accordance with the reconstructed images using ADMIRE. Conclusion: Texture analysis and SSIM allow a more realistic assessment of the dose reduction potential of iterative reconstruction algorithms than quality metrics only based on physical measurements of noise distribution or spatial resolution. This work presented that by means of the ADMIRE algorithm, a comparable image quality at reduced radiation doses can be reached. In the other hand, the use of the ADMIRE algorithm improved image quality parameters, among others the spatial resolution, for the equal radiation dose.
European Journal of Radiology, 2018
Changes of lung density differed significantly between patients with / without early BOS. BOS pat... more Changes of lung density differed significantly between patients with / without early BOS. BOS patients had increased lung volume and decreased lung density. Changes indicate increased inflation and were pronounced in the lower lung lobes.
Weiterbildung Radiologie, 2015
Poster: "ECR 2010 / C-3168 / Typical imaging findings of primary sarcomas of the great vesse... more Poster: "ECR 2010 / C-3168 / Typical imaging findings of primary sarcomas of the great vessels in CT, MRI and 18F-FDG PET/CT" by: "C. von Falck, C. Fegbeutel, F. Laenger, H.-O. Shin, S. Waldeck, W. H. Knapp, S. Fischer, M. Galanski; Hannover/DE"
Chest, 2021
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
European Respiratory Journal, 2020
European Radiology
Objectives Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and a highly va... more Objectives Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and a highly variable course. Pathologically increased ventilation—accessible by functional CT—is discussed as a potential predecessor of lung fibrosis. The purpose of this feasibility study was to investigate whether increased regional ventilation at baseline CT and morphological changes in the follow-up CT suggestive for fibrosis indeed occur in spatial correspondence. Methods In this retrospective study, CT scans were performed at two time points between September 2016 and November 2020. Baseline ventilation was divided into four categories ranging from low, normal to moderately, and severely increased (C1–C4). Correlation between baseline ventilation and volume and density change at follow-up was investigated in corresponding voxels. The significance of the difference of density and volume change per ventilation category was assessed using paired t-tests with a significance level of p ≤ 0.05. The a...
Poster: "ECR 2012 / C-2567 / Correlation of bronchial wall thickness with lung function para... more Poster: "ECR 2012 / C-2567 / Correlation of bronchial wall thickness with lung function parameters in patients after lung transplantation" by: "S. Dettmer1, C. de Wall1, L. Peters1, M. Schmidt2, F. Wacker1, H.-O. Shin1; 1Hannover/DE, 2Bremen/DE"
Poster: "ECR 2012 / C-0782 / Preoperative imaging of candidate donors for living donor liver... more Poster: "ECR 2012 / C-0782 / Preoperative imaging of candidate donors for living donor liver transplantation (LDLT) – What the radiologist needs to know" by: "K. I. Ringe1, J. Weidemann1, B. P. Ringe1, H.-O. Shin1, F. Wacker1, B. Ringe2; 1Hannover/DE, 2Philadelphia, PA/US"
Der Chirurg, 2015
ABSTRACT
protocols.io, Jan 8, 2019
Objectives Objectives: To evaluate frequency and severity of complications after CT-guided lung b... more Objectives Objectives: To evaluate frequency and severity of complications after CT-guided lung biopsy using the Society of Interventional Radiology (SIR) classification, and to assess risk factors for overall and major complications. Methods: Methods: 311 consecutive biopsies with a non-coaxial semi-automated 18 gauge biopsy system were retrospectively evaluated. Complications after biopsy were classified into minor SIR1-2 and major SIR3-6. Studied risk factors for complications were patient-related (age, sex and underlying emphysema), lesion-related (size, location, morphologic characteristics, depth from the pleura and histopathology), and technique-related (patient position during procedure, thoracic wall thickness at needle path, procedure time length and number of procedural CT images, number of pleural passes, fissure penetration and needle-to-blood vessel angle). Data were analyzed using logistic and ordinal regression. Results: Results: Complications were pneumothorax and pulmonary hemorrhage. The complications were minor SIR1-2 in 142 patients (45.6%), and major SIR3-4 in 25 patients (8%). SIR5-6 complications were not present. Emphysema, smaller deeply located lesion, increased puncture time length and number of procedural CT images, multiple pleural passes and fissure puncture were significant risk factors for complications severity in univariate analysis. Emphysema (OR=8.8, p<0.001), lesion depth from the pleura (OR=1.9 per cm, p<0.001), and fissure puncture (OR=9.4, p=0.01) were the independent factors for major complications in a multiple logistic regression model. No statistical difference of complications rate between the radiologists performing biopsies was observed. Conclusions: Conclusions: Knowledge about risk factors influencing complications severity is important for planning and performing CT-guided lung biopsies.
Objectives: To analyze the influence of multiplanar reformations of thincollimated multidetector ... more Objectives: To analyze the influence of multiplanar reformations of thincollimated multidetector computed tomography datasets on low-contrast performance. Materials and Methods: A low-contrast phantom simulating focal hypodense lesions (Ϫ20 HU object contrast) was scanned on a 64-slice spiral CT scanner at 4 different dose levels (25 mAs, 50 mAs, 100 mAs, 200 mAs, and no dose modulation). Other scanner parameters were as follows: tube voltage ϭ 120 kVp, rotation time ϭ 0.8 s, reconstructed slice thickness ϭ 0.625 mm, reconstruction interval ϭ 0.5 mm, reconstruction kernel ϭ standard. Coronal reformations were created using the open-source software OsiriX. A sliding-thin-slab (STS) averaging algorithm was applied to each axial and each reformatted dataset with an increasing slab thickness from 1 to 20 slices. The low-contrast performance of all datasets was calculated semiautomatically using a reader-independent, statistical approach and is expressed as the visibility index. The results were analyzed for differences between the coronal reformations and the original axial datasets. In addition, the statistical approach used herein was validated against a reader study. Results: The visibility index of the coronal reformatted datasets over all lesion sizes was inferior when compared with the original axial datasets and reached 75.4% (Ϯ11.7%), 79.9% (Ϯ16.3%), 79.4% (Ϯ5.5%), and 93.7% (Ϯ14.6%) for dose levels of 25, 50, 100, and 200 mAs, respectively. The overall mean low-contrast performance was 82.1% of the axial dataset (P Ͻ 0.05, except for 200 mAs). The deterioration of low-contrast performance was inversely correlated with lesion size (R 2 ϭ 0.91). The use of the STS averaging algorithm significantly improved image quality for all datasets (112.6%-180.2%) with the beneficial effect being stronger for the coronal reformations. There was no statistically significant difference in the evaluation of low-contrast performance between the statistical approach and the ready study. Conclusion: Coronal reformations of thin-collimated multidetector computed tomography datasets show a significant reduction of low-contrast performance when compared with the original axial dataset, especially in high noise data. The use of an STS averaging algorithm had a significant benefit for both, coronal and axial orientations. The effect was more pronounced with coronal reformations and should be routinely applied to improve image quality.
Nephrology Dialysis Transplantation, Jun 5, 2007
Zeitschrift Fur Orthopadie Und Unfallchirurgie, Jan 7, 2013
ABSTRACT
Pneumologie, Feb 23, 2017
Humanmedizin kompakt, Jul 20, 2014
arXiv (Cornell University), Sep 14, 2018
To evaluate the influence of a model-based iterative reconstruction algorithm (ADMIRE) on image t... more To evaluate the influence of a model-based iterative reconstruction algorithm (ADMIRE) on image texture and image visual impression as a supplement to measurements of common image quality parameters such as noise levels and spatial resolution. Methods: An American College of Radiology CT accreditation phantom (ACR phantom) was examined at different radiation dose levels expressed by the volumetric computed tomography dose index (CTDI vol = 0.67, 1.64, 3.31 and 6.65 mGy). To characterize the image texture, two Haralick texture parameters, i.e. contrast and entropy, for different dose level and reconstruction algorithms were assessed. The visual impression of images and their structural differences were evaluated using the structural similarity index (SSIM). Noise defined as the standard deviation of the voxel density was determined for all dose and AMIRE levels and compared to those by filtered back projection. The spatial resolution was determined by the modulation transfer functions and the line spread function. Results: The Haralick texture parameters, contrast and entropy, decreased with increasing ADMIRE levels I up to V. ADMIRE III, IV and V offered a comparable contrast and entropy to those calculated by the filter back projection with a radiation dose reduction up to 50%. On the other hand, SSIM improved with increasing ADMIRE levels. SSIM calculated by ADMIRE IV and V showed similar values by the filter back projection with a CTDI vol decrease up to 50%. Spatial resolution was retained up to 90% dose reduction. With increasing ADMIRE as well as dose level the noise distribution shifted to a more narrow distribution, which was in accordance with the reconstructed images using ADMIRE. Conclusion: Texture analysis and SSIM allow a more realistic assessment of the dose reduction potential of iterative reconstruction algorithms than quality metrics only based on physical measurements of noise distribution or spatial resolution. This work presented that by means of the ADMIRE algorithm, a comparable image quality at reduced radiation doses can be reached. In the other hand, the use of the ADMIRE algorithm improved image quality parameters, among others the spatial resolution, for the equal radiation dose.
European Journal of Radiology, 2018
Changes of lung density differed significantly between patients with / without early BOS. BOS pat... more Changes of lung density differed significantly between patients with / without early BOS. BOS patients had increased lung volume and decreased lung density. Changes indicate increased inflation and were pronounced in the lower lung lobes.
Weiterbildung Radiologie, 2015
Poster: "ECR 2010 / C-3168 / Typical imaging findings of primary sarcomas of the great vesse... more Poster: "ECR 2010 / C-3168 / Typical imaging findings of primary sarcomas of the great vessels in CT, MRI and 18F-FDG PET/CT" by: "C. von Falck, C. Fegbeutel, F. Laenger, H.-O. Shin, S. Waldeck, W. H. Knapp, S. Fischer, M. Galanski; Hannover/DE"
Chest, 2021
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
European Respiratory Journal, 2020
European Radiology
Objectives Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and a highly va... more Objectives Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and a highly variable course. Pathologically increased ventilation—accessible by functional CT—is discussed as a potential predecessor of lung fibrosis. The purpose of this feasibility study was to investigate whether increased regional ventilation at baseline CT and morphological changes in the follow-up CT suggestive for fibrosis indeed occur in spatial correspondence. Methods In this retrospective study, CT scans were performed at two time points between September 2016 and November 2020. Baseline ventilation was divided into four categories ranging from low, normal to moderately, and severely increased (C1–C4). Correlation between baseline ventilation and volume and density change at follow-up was investigated in corresponding voxels. The significance of the difference of density and volume change per ventilation category was assessed using paired t-tests with a significance level of p ≤ 0.05. The a...
Poster: "ECR 2012 / C-2567 / Correlation of bronchial wall thickness with lung function para... more Poster: "ECR 2012 / C-2567 / Correlation of bronchial wall thickness with lung function parameters in patients after lung transplantation" by: "S. Dettmer1, C. de Wall1, L. Peters1, M. Schmidt2, F. Wacker1, H.-O. Shin1; 1Hannover/DE, 2Bremen/DE"
Poster: "ECR 2012 / C-0782 / Preoperative imaging of candidate donors for living donor liver... more Poster: "ECR 2012 / C-0782 / Preoperative imaging of candidate donors for living donor liver transplantation (LDLT) – What the radiologist needs to know" by: "K. I. Ringe1, J. Weidemann1, B. P. Ringe1, H.-O. Shin1, F. Wacker1, B. Ringe2; 1Hannover/DE, 2Philadelphia, PA/US"
Der Chirurg, 2015
ABSTRACT