Endoscopic ultrasonography(EUS) is currently an in-tegral investigation of many gastrointestinal disorders.It has been shown to have a higher efficacy thanconventional computed tomography in detection andcharacterizat...Endoscopic ultrasonography(EUS) is currently an in-tegral investigation of many gastrointestinal disorders.It has been shown to have a higher efficacy thanconventional computed tomography in detection andcharacterization of small lesions especially in the pan-creas. Much effort has been put to further improvethe sensitivity, specificity and overall accuracy of EUS.One of the major advances is the utilization of contrastagents for better delineation of the vascularity and tis-sue perfusion of the target lesion. This article describesthe basic principles of ultrasound contrast agents andthe different modalities used in contrast-enhanced EUS(CE-EUS) including contrast-enhanced Doppler EUS(CED-EUS) and contrast-enhanced harmonic EUS(CEH-EUS). In addition, the current applications of contrastenhanced EUS in different gastrointestinal conditionswere discussed. Furthermore, the future developmentof hybrid approaches combining CE-EUS with other im-aging modalities and the potential therapeutic aspectof using it as a vector for drug delivery were also dis-cussed.展开更多
It is important to segment mass region accurately in a computer-aided diagnosis (CADx) scheme for evaluating the likelihood of malignancy of the mass on ultrasonographic breast image. The purpose of this study was to ...It is important to segment mass region accurately in a computer-aided diagnosis (CADx) scheme for evaluating the likelihood of malignancy of the mass on ultrasonographic breast image. The purpose of this study was to develop a novel level set method for segmentation of breast mass on ultrasonographic image. Our database consisted of 151 ultrasonographic images with 70 malignant and 81 benign breast masses. In a novel level set method, an energy function was defined with region-based, edge-based, and regularizing terms. The region-based term analyzed global information, whereas the edge-based term analyzed local information. The regularizing term also controlled the length of the boundary curve. The region of breast mass was segmented so that the energy based on those terms was minimized. With our proposed method, true positive (TP) ratio, false positive (FP) ratio, jaccard similarity (JS), and Dice similarity coefficient (DSC) were 92.2%, 9.1%, 84.2%, and 91.3%, respectively. These results tended to be substantially higher than those with two conventional segmentation methods. Our proposed method based on the novel level set method was shown to segment mass region accurately on ultrasonographic breast image.展开更多
Architectural distortion is an important ultrasonographic indicator of breast cancer. However, it is difficult for clinicians to determine whether a given lesion is malignant because such distortions can be subtle in ...Architectural distortion is an important ultrasonographic indicator of breast cancer. However, it is difficult for clinicians to determine whether a given lesion is malignant because such distortions can be subtle in ultrasonographic images. In this paper, we report on a study to develop a computerized scheme for the histological classification of masses with architectural distortions as a differential diagnosis aid. Our database consisted of 72 ultrasonographic images obtained from 47 patients whose masses had architectural distortions. This included 51 malignant (35 invasive and 16 non-invasive carcinomas) and 21 benign masses. In the proposed method, the location of the masses and the area occupied by them were first determined by an experienced clinician. Fourteen objective features concerning masses with architectural distortions were then extracted automatically by taking into account subjective features commonly used by experienced clinicians to describe such masses. The k-nearest neighbors (k-NN) rule was finally used to distinguish three histological classifications. The proposed method yielded classification accuracy values of 91.4% (32/35) for invasive carcinoma, 75.0% (12/16) for noninvasive carcinoma, and 85.7% (18/21) for benign mass, respectively. The sensitivity and specificity values were 92.2% (47/51) and 85.7% (18/21), respectively. The positive predictive values (PPV) were 88.9% (32/36) for invasive carcinoma and 85.7% (12/14) for noninvasive carcinoma whereas the negative predictive values (NPV) were 81.8% (18/22) for benign mass. Thus, the proposed method can help the differential diagnosis of masses with architectural distortions in ultrasonographic images.展开更多
Goal: The goal of this study is to define the epidemiological profile and identify the different brain lesions diagnosed in ultrasonography in preterm infants in Benin environment. Patients and methods: It is a prospe...Goal: The goal of this study is to define the epidemiological profile and identify the different brain lesions diagnosed in ultrasonography in preterm infants in Benin environment. Patients and methods: It is a prospective cross-sectional study of analytical aiming. It took place over a period of 6 months, from May 1<sup>st</sup> to October 31<sup>st</sup>, 2012 at the National Hospital University Centre Koutoukou Hubert Maga in neonatal units and medical scanning unit. It covered 105 premature newborn, classified into the very prematurity and the moderate prematurity. Results: The very premature represented 35.2% and the moderate premature 64.8%, with an average of 33.5% and 1.9 of standard deviation. The average age when implementing ultrasonographic transfontanellar was 7.2 ± 4.6 days old. The lowest birth weight was observed in very premature with p = 0.0025. The nasopharyngeal septum pellucidum was the most found lesions in 46 preterm infants (43.8%) with no statistically significantly difference in two groups, followed by the ventricular haemorrhage found in 21 preterm infants accounting for 20%, and the grade 1 or sub-ependymal haemorrhage prevailed in 14 premature accounting for 66.7%, afterward periventricular leukomalacia in 4 premature infants and hydrocephalus in 2 premature. Conclusion: The nasopharyngeal septum pellucidum and the sub-ependymal ventricular haemorrhage were the predominant anomalies in premature infants followed by leukomalacia.展开更多
文摘Endoscopic ultrasonography(EUS) is currently an in-tegral investigation of many gastrointestinal disorders.It has been shown to have a higher efficacy thanconventional computed tomography in detection andcharacterization of small lesions especially in the pan-creas. Much effort has been put to further improvethe sensitivity, specificity and overall accuracy of EUS.One of the major advances is the utilization of contrastagents for better delineation of the vascularity and tis-sue perfusion of the target lesion. This article describesthe basic principles of ultrasound contrast agents andthe different modalities used in contrast-enhanced EUS(CE-EUS) including contrast-enhanced Doppler EUS(CED-EUS) and contrast-enhanced harmonic EUS(CEH-EUS). In addition, the current applications of contrastenhanced EUS in different gastrointestinal conditionswere discussed. Furthermore, the future developmentof hybrid approaches combining CE-EUS with other im-aging modalities and the potential therapeutic aspectof using it as a vector for drug delivery were also dis-cussed.
文摘It is important to segment mass region accurately in a computer-aided diagnosis (CADx) scheme for evaluating the likelihood of malignancy of the mass on ultrasonographic breast image. The purpose of this study was to develop a novel level set method for segmentation of breast mass on ultrasonographic image. Our database consisted of 151 ultrasonographic images with 70 malignant and 81 benign breast masses. In a novel level set method, an energy function was defined with region-based, edge-based, and regularizing terms. The region-based term analyzed global information, whereas the edge-based term analyzed local information. The regularizing term also controlled the length of the boundary curve. The region of breast mass was segmented so that the energy based on those terms was minimized. With our proposed method, true positive (TP) ratio, false positive (FP) ratio, jaccard similarity (JS), and Dice similarity coefficient (DSC) were 92.2%, 9.1%, 84.2%, and 91.3%, respectively. These results tended to be substantially higher than those with two conventional segmentation methods. Our proposed method based on the novel level set method was shown to segment mass region accurately on ultrasonographic breast image.
文摘Architectural distortion is an important ultrasonographic indicator of breast cancer. However, it is difficult for clinicians to determine whether a given lesion is malignant because such distortions can be subtle in ultrasonographic images. In this paper, we report on a study to develop a computerized scheme for the histological classification of masses with architectural distortions as a differential diagnosis aid. Our database consisted of 72 ultrasonographic images obtained from 47 patients whose masses had architectural distortions. This included 51 malignant (35 invasive and 16 non-invasive carcinomas) and 21 benign masses. In the proposed method, the location of the masses and the area occupied by them were first determined by an experienced clinician. Fourteen objective features concerning masses with architectural distortions were then extracted automatically by taking into account subjective features commonly used by experienced clinicians to describe such masses. The k-nearest neighbors (k-NN) rule was finally used to distinguish three histological classifications. The proposed method yielded classification accuracy values of 91.4% (32/35) for invasive carcinoma, 75.0% (12/16) for noninvasive carcinoma, and 85.7% (18/21) for benign mass, respectively. The sensitivity and specificity values were 92.2% (47/51) and 85.7% (18/21), respectively. The positive predictive values (PPV) were 88.9% (32/36) for invasive carcinoma and 85.7% (12/14) for noninvasive carcinoma whereas the negative predictive values (NPV) were 81.8% (18/22) for benign mass. Thus, the proposed method can help the differential diagnosis of masses with architectural distortions in ultrasonographic images.
文摘Goal: The goal of this study is to define the epidemiological profile and identify the different brain lesions diagnosed in ultrasonography in preterm infants in Benin environment. Patients and methods: It is a prospective cross-sectional study of analytical aiming. It took place over a period of 6 months, from May 1<sup>st</sup> to October 31<sup>st</sup>, 2012 at the National Hospital University Centre Koutoukou Hubert Maga in neonatal units and medical scanning unit. It covered 105 premature newborn, classified into the very prematurity and the moderate prematurity. Results: The very premature represented 35.2% and the moderate premature 64.8%, with an average of 33.5% and 1.9 of standard deviation. The average age when implementing ultrasonographic transfontanellar was 7.2 ± 4.6 days old. The lowest birth weight was observed in very premature with p = 0.0025. The nasopharyngeal septum pellucidum was the most found lesions in 46 preterm infants (43.8%) with no statistically significantly difference in two groups, followed by the ventricular haemorrhage found in 21 preterm infants accounting for 20%, and the grade 1 or sub-ependymal haemorrhage prevailed in 14 premature accounting for 66.7%, afterward periventricular leukomalacia in 4 premature infants and hydrocephalus in 2 premature. Conclusion: The nasopharyngeal septum pellucidum and the sub-ependymal ventricular haemorrhage were the predominant anomalies in premature infants followed by leukomalacia.
