Jyh-Wen Chai - Academia.edu (original) (raw)
Papers by Jyh-Wen Chai
Journal of Industrial and Production Engineering, 2015
Colorectal Cancer, 2009
Despite advances made in surgical techniques, antibiotics use and supportive care in recent years... more Despite advances made in surgical techniques, antibiotics use and supportive care in recent years, abdominal infection due to an anastomotic leakage remains one of the most dangerous complications following colorectal surgery. The current trend for surgical management of colorectal cancer has changed from conventional open approach to minimal invasive laparoscopic colectomy (Finlayson and Nelson, 2005). The anas-tomotic leakage rate after
Journal of the Chinese Medical Association, 2007
American Journal of Rhinology and Allergy, 2009
Olfactory bulb (OB) volume has been shown to be an indicator of olfactory function. However, few ... more Olfactory bulb (OB) volume has been shown to be an indicator of olfactory function. However, few studies have been done in Asia to investigate the influence of different disorders on OB volume. Data from patients with posttraumatic anosmia were collected in our department. Their olfactory thresholds were assessed by the phenyl ethyl alcohol threshold test. They were treated with a course of high-dose steroid, and followed up for at least 3 months without any olfactory improvement. Magnetic resonance imaging was subsequently used to measure patients' OB volumes. Subjects who self-reported their olfactory function was normal were also included in the control group for comparison. Fifty-four patients with posttraumatic anosmia and 30 subjects who self-reported their olfactory function was normal were enrolled in this study. The mean right OB volume was 45.2 mm3, and the mean left OB volume was 46.3 mm3 in patients with posttraumatic anosmia. The mean right OB volume was 59.7 mm3, and the mean left OB volume was 66.0 mm3 in control subjects. The OB volumes were significantly lower in patients with posttraumatic anosmia. OB volumes were significantly lower in Taiwanese patients with posttraumatic anosmia.
Journal of Cardiovascular Magnetic Resonance, 2009
Iranian Journal of Radiology, 2016
The international journal of cardiovascular imaging, Jan 25, 2016
In this study, we aimed to evaluate whether patients with left to right shunt coronary artery fis... more In this study, we aimed to evaluate whether patients with left to right shunt coronary artery fistula (LRSCAF) are predisposed to developing pulmonary hypertension and right ventricular dysfunction compared with healthy individuals. The value of cardiac CT findings in determining the necessity of intervention for these patients was investigated. We retrospectively studied 19 patients with LRSCAF and 19 healthy patients. Several parameters were observed on cardiac CT by two radiologists, including pulmonary trunk diameter (PA diameter), right ventricular diameter (RVD), left ventricular diameter (LVD), RVD/LVD ratio, septal bowing and CT score of right ventricular dysfunction (CSRVD). Data from both groups were compared. The inter- and intra-observer variabilities and correlations were examined. The disease group was further divided into intervention (n = 9) and non-intervention (n = 10) groups, and their data were compared. All cardiac CT findings showed significant intra- and inter...
Journal of Cardiovascular Magnetic Resonance, 2016
Journal of the Chinese Institute of Engineers, 2015
Translational oncology, 2015
C-arm cone-beam computed tomography (CBCT) is a comparatively novel modality for guiding percutan... more C-arm cone-beam computed tomography (CBCT) is a comparatively novel modality for guiding percutaneous transthoracic lung biopsies (PTLBs), and despite its potential advantages over conventional computed tomography (CCT), a head-to-head comparison of the two techniques has yet to be reported in the literature. This study aims to evaluate the diagnostic value and safety of CBCT-guided PTLB compared to CCT-guided biopsy, with cases performed in a single hospital. A total of 104 PTLB patients were retrospectively analyzed in this study. 35 PTLBs were performed under CBCT guidance, and 69 PTLBs were performed under CCT guidance. Diagnostic accuracy, sensitivity, and specificity for malignancy as well as procedure time, radiation dose of patients, and complication rate in the two groups were compared. Total procedure time was significantly lower in the CBCT group (32 ± 11 minutes) compared to the CCT group (38 ± 9.7 minutes; P = .009), especially among patients ≥70 years of age (CBCT: 33 ...
Journal of Cardiovascular Magnetic Resonance, 2015
To evaluate retrospectively the optimized biphasic computed tomographic (CT) findings of focal no... more To evaluate retrospectively the optimized biphasic computed tomographic (CT) findings of focal nodular hyperplasia (FNH) that might facilitate cor- rect diagnosis. Biphasic helical CT scans were performed in 28 patients with 40 FNH lesions. Hepatic arterial phase (HAP) and delayed venous phase (DVP) images were obtained initially at 20-25 and 120 seconds, respectively. Diagnosis was based on complete resec- tion (n = 9), MRI (magnetic resonance image) (n = 12) or CT (n = 7) follow-up for a minimum of 6 months without evidence of significant change. We evaluated the number, size, location, margins, sur- face, homogeneity of enhancement, and presence of central scar, mass effect, calcification, or vessels feeding or draining the lesion. Forty tumors (mean diameter, 4.2 cm; range, 1-9.5 cm) were seen. The large lesion group included 18 nodules larger than 3 cm in diameter. Typical imaging features of FNHs included strong, homogeneous contrast enhance- ment on HAP images and isodensity ...
The neuroradiology journal, Jan 30, 2007
A simple gradient-echo arterial spin tagging (GREAST) technique allows for quick assessment of re... more A simple gradient-echo arterial spin tagging (GREAST) technique allows for quick assessment of regional tissue perfusion without the need for exogenous contrast agent. The purpose of this prospective study was to validate GREAST imaging in characterizing the regional perfusion status of focal brain lesions by comparing with relative cerebral blood volume (rCBV) maps obtained by using echo-planar imaging (EPI)-based dynamic susceptibility contrast MR imaging. Thirty-two patients whose nonenhanced brain MR images showed 34 focal brain lesions during routine examination were selected to immediately undergo GREAST and dynamic susceptibility contrast MR imaging to evaluate regional perfusion of the lesions. The Pearson correlation coefficient was used to test the relative quantification of local perfusion with the two imaging methods. Qualitative perfusion measurements agreed in 23 (79%) of 29 lesions for which GREAST and dynamic susceptibility contrast MR imaging were successful. On rCB...
PLOS ONE, 2015
A new TRIO algorithm method integrating three different algorithms is proposed to perform brain M... more A new TRIO algorithm method integrating three different algorithms is proposed to perform brain MRI segmentation in the native coordinate space, with no need of transformation to a standard coordinate space or the probability maps for segmentation. The method is a simple voxel-based algorithm, derived from multispectral remote sensing techniques, and only requires minimal operator input to depict GM, WM, and CSF tissue clusters to complete classification of a 3D high-resolution multislice-multispectral MRI data. Results showed very high accuracy and reproducibility in classification of GM, WM, and CSF in multislice-multispectral synthetic MRI data. The similarity indexes, expressing overlap between classification results and the ground truth, were 0.951, 0.962, and 0.956 for GM, WM, and CSF classifications in the image data with 3% noise level and 0% non-uniformity intensity. The method particularly allows for classification of CSF with 0.994, 0.961 and 0.996 of accuracy, sensitivity and specificity in images data with 3% noise level and 0% non-uniformity intensity, which had seldom performed well in previous studies. As for clinical MRI data, the quantitative data of brain tissue volumes aligned closely with the brain morphometrics in three different study groups of young adults, elderly volunteers, and dementia patients. The results also showed very low rates of the intra- and extra-operator variability in measurements of the absolute volumes and volume fractions of cerebral GM, WM, and CSF in three different study groups. The mean coefficients of variation of GM, WM, and CSF volume measurements were in the range of 0.03% to 0.30% of intra-operator measurements and 0.06% to 0.45% of inter-operator measurements. In conclusion, the TRIO algorithm exhibits a remarkable ability in robust classification of multislice-multispectral brain MR images, which would be potentially applicable for clinical brain volumetric analysis and explicitly promising in cross-sectional and longitudinal studies of different subject groups.
2010 Fourth International Conference on Genetic and Evolutionary Computing, 2010
Page 1. Techniques for Automatic Magnetic Resonance Image Classification Hsian-Min Chen1, Shih-Yu... more Page 1. Techniques for Automatic Magnetic Resonance Image Classification Hsian-Min Chen1, Shih-Yu Chen2, Jyh Wen Chai3,4, Clayton Chi-Chang Chen4,5, Chao-Cheng Wu6, Yen-Chieh Ouyang2, Ching Tsorng Tsai7, Ching-Wen Yang8, San-Kan Lee4, Chein-I Chang9 ...
2010 Fourth International Conference on Genetic and Evolutionary Computing, 2010
This paper develops a volume-based technique, called Volume Sphering Analysis (VSA) which can pro... more This paper develops a volume-based technique, called Volume Sphering Analysis (VSA) which can process all acquired Magnetic Resonance (MR) image slicesformed image cube using only one set of training samples obtained from an image slice. So, several significant advantages and benefits can be gained from our proposed VSA. In the past, when MR image classification is performed, each image slice requires its own specific training samples and training samples obtained from one slice are not applied to another slice. The VSA allows users to reduce computational time. In addition, it saves significant effort in selecting training samples for each of image slices. Thirdly, it is robust to all image slices compared to the traditional one-slice MR image classification which is sensitive to each image slice. Experimental results demonstrate that the VSA performs as well as does that using specifically selected training samples for individual image slices.
2009 Ninth IEEE International Conference on Bioinformatics and BioEngineering, 2009
The purpose of this study is to present a new method, independent vector analysis (IVA), by exten... more The purpose of this study is to present a new method, independent vector analysis (IVA), by extending independent component analysis (ICA) of univariate source signals to multivariate source signals on Magnetic Resonance Imaging (MRI). IVA is utilized to relief the limitation of the ...
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2005
This paper presents a new application of independent component analysis (ICA) in magnetic resonan... more This paper presents a new application of independent component analysis (ICA) in magnetic resonance (MR) image analysis. One of most successful applications for ICA-based approaches in MR imaging is functional MRI (fMRI) which basically deals with one-dimensional temporal signals. The ICA approach proposed in this paper is rather different and considers a set of MR images acquired by different pulse sequences as a 3-dimensional image cube and performs image analysis rather than signal analysis. One major difference between the fMRI- based ICA approaches and our proposed ICA-based image analysis is that the ICA used in the former is under-complete as opposed to the latter which uses over-complete ICA. Such a fundamental difference results in completely different applications.
Magnetic Resonance in Medicine, 1995
Magnetic Resonance in Medicine, 1996
By using on-resonance binomial pulse saturation of the immobile component in tissues and by monit... more By using on-resonance binomial pulse saturation of the immobile component in tissues and by monitoring the time development of the longitudinal decay of the free water magnetization, it has been shown that it is possible to estimate physical model parameters not directly measurable by conventional methods. Since pulsed saturation is easy and safe to implement in a clinical MRI machine, it should be possible to estimate these parameters in vivo by the same means. In this article, we report the results of such estimates of the parameters of the principal components (gray and white matter) in brains of two normal volunteers.
Journal of Industrial and Production Engineering, 2015
Colorectal Cancer, 2009
Despite advances made in surgical techniques, antibiotics use and supportive care in recent years... more Despite advances made in surgical techniques, antibiotics use and supportive care in recent years, abdominal infection due to an anastomotic leakage remains one of the most dangerous complications following colorectal surgery. The current trend for surgical management of colorectal cancer has changed from conventional open approach to minimal invasive laparoscopic colectomy (Finlayson and Nelson, 2005). The anas-tomotic leakage rate after
Journal of the Chinese Medical Association, 2007
American Journal of Rhinology and Allergy, 2009
Olfactory bulb (OB) volume has been shown to be an indicator of olfactory function. However, few ... more Olfactory bulb (OB) volume has been shown to be an indicator of olfactory function. However, few studies have been done in Asia to investigate the influence of different disorders on OB volume. Data from patients with posttraumatic anosmia were collected in our department. Their olfactory thresholds were assessed by the phenyl ethyl alcohol threshold test. They were treated with a course of high-dose steroid, and followed up for at least 3 months without any olfactory improvement. Magnetic resonance imaging was subsequently used to measure patients' OB volumes. Subjects who self-reported their olfactory function was normal were also included in the control group for comparison. Fifty-four patients with posttraumatic anosmia and 30 subjects who self-reported their olfactory function was normal were enrolled in this study. The mean right OB volume was 45.2 mm3, and the mean left OB volume was 46.3 mm3 in patients with posttraumatic anosmia. The mean right OB volume was 59.7 mm3, and the mean left OB volume was 66.0 mm3 in control subjects. The OB volumes were significantly lower in patients with posttraumatic anosmia. OB volumes were significantly lower in Taiwanese patients with posttraumatic anosmia.
Journal of Cardiovascular Magnetic Resonance, 2009
Iranian Journal of Radiology, 2016
The international journal of cardiovascular imaging, Jan 25, 2016
In this study, we aimed to evaluate whether patients with left to right shunt coronary artery fis... more In this study, we aimed to evaluate whether patients with left to right shunt coronary artery fistula (LRSCAF) are predisposed to developing pulmonary hypertension and right ventricular dysfunction compared with healthy individuals. The value of cardiac CT findings in determining the necessity of intervention for these patients was investigated. We retrospectively studied 19 patients with LRSCAF and 19 healthy patients. Several parameters were observed on cardiac CT by two radiologists, including pulmonary trunk diameter (PA diameter), right ventricular diameter (RVD), left ventricular diameter (LVD), RVD/LVD ratio, septal bowing and CT score of right ventricular dysfunction (CSRVD). Data from both groups were compared. The inter- and intra-observer variabilities and correlations were examined. The disease group was further divided into intervention (n = 9) and non-intervention (n = 10) groups, and their data were compared. All cardiac CT findings showed significant intra- and inter...
Journal of Cardiovascular Magnetic Resonance, 2016
Journal of the Chinese Institute of Engineers, 2015
Translational oncology, 2015
C-arm cone-beam computed tomography (CBCT) is a comparatively novel modality for guiding percutan... more C-arm cone-beam computed tomography (CBCT) is a comparatively novel modality for guiding percutaneous transthoracic lung biopsies (PTLBs), and despite its potential advantages over conventional computed tomography (CCT), a head-to-head comparison of the two techniques has yet to be reported in the literature. This study aims to evaluate the diagnostic value and safety of CBCT-guided PTLB compared to CCT-guided biopsy, with cases performed in a single hospital. A total of 104 PTLB patients were retrospectively analyzed in this study. 35 PTLBs were performed under CBCT guidance, and 69 PTLBs were performed under CCT guidance. Diagnostic accuracy, sensitivity, and specificity for malignancy as well as procedure time, radiation dose of patients, and complication rate in the two groups were compared. Total procedure time was significantly lower in the CBCT group (32 ± 11 minutes) compared to the CCT group (38 ± 9.7 minutes; P = .009), especially among patients ≥70 years of age (CBCT: 33 ...
Journal of Cardiovascular Magnetic Resonance, 2015
To evaluate retrospectively the optimized biphasic computed tomographic (CT) findings of focal no... more To evaluate retrospectively the optimized biphasic computed tomographic (CT) findings of focal nodular hyperplasia (FNH) that might facilitate cor- rect diagnosis. Biphasic helical CT scans were performed in 28 patients with 40 FNH lesions. Hepatic arterial phase (HAP) and delayed venous phase (DVP) images were obtained initially at 20-25 and 120 seconds, respectively. Diagnosis was based on complete resec- tion (n = 9), MRI (magnetic resonance image) (n = 12) or CT (n = 7) follow-up for a minimum of 6 months without evidence of significant change. We evaluated the number, size, location, margins, sur- face, homogeneity of enhancement, and presence of central scar, mass effect, calcification, or vessels feeding or draining the lesion. Forty tumors (mean diameter, 4.2 cm; range, 1-9.5 cm) were seen. The large lesion group included 18 nodules larger than 3 cm in diameter. Typical imaging features of FNHs included strong, homogeneous contrast enhance- ment on HAP images and isodensity ...
The neuroradiology journal, Jan 30, 2007
A simple gradient-echo arterial spin tagging (GREAST) technique allows for quick assessment of re... more A simple gradient-echo arterial spin tagging (GREAST) technique allows for quick assessment of regional tissue perfusion without the need for exogenous contrast agent. The purpose of this prospective study was to validate GREAST imaging in characterizing the regional perfusion status of focal brain lesions by comparing with relative cerebral blood volume (rCBV) maps obtained by using echo-planar imaging (EPI)-based dynamic susceptibility contrast MR imaging. Thirty-two patients whose nonenhanced brain MR images showed 34 focal brain lesions during routine examination were selected to immediately undergo GREAST and dynamic susceptibility contrast MR imaging to evaluate regional perfusion of the lesions. The Pearson correlation coefficient was used to test the relative quantification of local perfusion with the two imaging methods. Qualitative perfusion measurements agreed in 23 (79%) of 29 lesions for which GREAST and dynamic susceptibility contrast MR imaging were successful. On rCB...
PLOS ONE, 2015
A new TRIO algorithm method integrating three different algorithms is proposed to perform brain M... more A new TRIO algorithm method integrating three different algorithms is proposed to perform brain MRI segmentation in the native coordinate space, with no need of transformation to a standard coordinate space or the probability maps for segmentation. The method is a simple voxel-based algorithm, derived from multispectral remote sensing techniques, and only requires minimal operator input to depict GM, WM, and CSF tissue clusters to complete classification of a 3D high-resolution multislice-multispectral MRI data. Results showed very high accuracy and reproducibility in classification of GM, WM, and CSF in multislice-multispectral synthetic MRI data. The similarity indexes, expressing overlap between classification results and the ground truth, were 0.951, 0.962, and 0.956 for GM, WM, and CSF classifications in the image data with 3% noise level and 0% non-uniformity intensity. The method particularly allows for classification of CSF with 0.994, 0.961 and 0.996 of accuracy, sensitivity and specificity in images data with 3% noise level and 0% non-uniformity intensity, which had seldom performed well in previous studies. As for clinical MRI data, the quantitative data of brain tissue volumes aligned closely with the brain morphometrics in three different study groups of young adults, elderly volunteers, and dementia patients. The results also showed very low rates of the intra- and extra-operator variability in measurements of the absolute volumes and volume fractions of cerebral GM, WM, and CSF in three different study groups. The mean coefficients of variation of GM, WM, and CSF volume measurements were in the range of 0.03% to 0.30% of intra-operator measurements and 0.06% to 0.45% of inter-operator measurements. In conclusion, the TRIO algorithm exhibits a remarkable ability in robust classification of multislice-multispectral brain MR images, which would be potentially applicable for clinical brain volumetric analysis and explicitly promising in cross-sectional and longitudinal studies of different subject groups.
2010 Fourth International Conference on Genetic and Evolutionary Computing, 2010
Page 1. Techniques for Automatic Magnetic Resonance Image Classification Hsian-Min Chen1, Shih-Yu... more Page 1. Techniques for Automatic Magnetic Resonance Image Classification Hsian-Min Chen1, Shih-Yu Chen2, Jyh Wen Chai3,4, Clayton Chi-Chang Chen4,5, Chao-Cheng Wu6, Yen-Chieh Ouyang2, Ching Tsorng Tsai7, Ching-Wen Yang8, San-Kan Lee4, Chein-I Chang9 ...
2010 Fourth International Conference on Genetic and Evolutionary Computing, 2010
This paper develops a volume-based technique, called Volume Sphering Analysis (VSA) which can pro... more This paper develops a volume-based technique, called Volume Sphering Analysis (VSA) which can process all acquired Magnetic Resonance (MR) image slicesformed image cube using only one set of training samples obtained from an image slice. So, several significant advantages and benefits can be gained from our proposed VSA. In the past, when MR image classification is performed, each image slice requires its own specific training samples and training samples obtained from one slice are not applied to another slice. The VSA allows users to reduce computational time. In addition, it saves significant effort in selecting training samples for each of image slices. Thirdly, it is robust to all image slices compared to the traditional one-slice MR image classification which is sensitive to each image slice. Experimental results demonstrate that the VSA performs as well as does that using specifically selected training samples for individual image slices.
2009 Ninth IEEE International Conference on Bioinformatics and BioEngineering, 2009
The purpose of this study is to present a new method, independent vector analysis (IVA), by exten... more The purpose of this study is to present a new method, independent vector analysis (IVA), by extending independent component analysis (ICA) of univariate source signals to multivariate source signals on Magnetic Resonance Imaging (MRI). IVA is utilized to relief the limitation of the ...
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2005
This paper presents a new application of independent component analysis (ICA) in magnetic resonan... more This paper presents a new application of independent component analysis (ICA) in magnetic resonance (MR) image analysis. One of most successful applications for ICA-based approaches in MR imaging is functional MRI (fMRI) which basically deals with one-dimensional temporal signals. The ICA approach proposed in this paper is rather different and considers a set of MR images acquired by different pulse sequences as a 3-dimensional image cube and performs image analysis rather than signal analysis. One major difference between the fMRI- based ICA approaches and our proposed ICA-based image analysis is that the ICA used in the former is under-complete as opposed to the latter which uses over-complete ICA. Such a fundamental difference results in completely different applications.
Magnetic Resonance in Medicine, 1995
Magnetic Resonance in Medicine, 1996
By using on-resonance binomial pulse saturation of the immobile component in tissues and by monit... more By using on-resonance binomial pulse saturation of the immobile component in tissues and by monitoring the time development of the longitudinal decay of the free water magnetization, it has been shown that it is possible to estimate physical model parameters not directly measurable by conventional methods. Since pulsed saturation is easy and safe to implement in a clinical MRI machine, it should be possible to estimate these parameters in vivo by the same means. In this article, we report the results of such estimates of the parameters of the principal components (gray and white matter) in brains of two normal volunteers.