Multi Modality State-of-the-Art Medical Image Segmentation and Registration Methodologies, 2011
Ocular surface temperature relates deeply with ocular physiology. It is nowadays looked into main... more Ocular surface temperature relates deeply with ocular physiology. It is nowadays looked into mainly by the use of infrared thermography, and occasionally functional infrared imaging. In this study, we recorded ocular thermographic sequences of 60 normal subjects; 30 of them were young and the rest were the elderly. Ocular region in the thermographic sequences was warped to a standardized form, and the eyelashes in each thermographic image were identified and avoided for further analysis. Average horizontal, vertical temperature profiles were unambiguously defined in the warped thermographic sequences. They were extracted, and comparisons were made between the young and the elderly. It was found that the elder subjects exhibited a cooler temperature profile, but their temperature differences between corneal center and limbus were generally higher.
Breast cancer is the second leading cause of death in women. It occurs when cells in the breast b... more Breast cancer is the second leading cause of death in women. It occurs when cells in the breast begin to grow out of control and invade nearby tissues or spread throughout the body. The limitations of mammography as a screening modality, especially in young women with denser breasts, necessitated the development of novel and more effective screening strategies with acceptable sensitivity and specificity. The aim of this study was to develop a feasible interpretive software system which was able to detect and classify breast cancer patients by employing techniques of different analytical software. The protocol described uses 6,000 pieces of thermal data collected from 16-sensors, eight placed on the surface of each breast. Data was collected every 5 min for the duration of the test period. Placement of sensors was accomplished with the use of a template design from information provided by the national tumor registry to insure that the information was collected in areas of the breast where most breast cancers develop. Data in this study was collected from 90 individuals exhibiting four different breast conditions, namely: normal, benign, cancer and suspected-cancer. The temperature data collected from these 16 sensors placed on the surface of each breast were fed as inputs to the classifiers. Comparisons were made on five different kinds of classifiers: back-propagation algorithm, probabilistic neural network, fuzzy (Sugeno-type), Gaussian mixture model and support vector machine. These classifiers were able to attain approximately 80% accuracy in classifying the four different diagnoses (normal, benign, cancer and suspected-cancer). Gaussian mixture model was the most sensitive classifier, achieving the highest sensitivity of 94.8%. Support vector machine was considered the best classifier as it was able to produce the most specific and accurate results. Based on these evaluations, this current effort shows the feasibility of applying analytical software techniques together with the real-time functional thermal analysis to develop a potential tool for the detection and classification of breast cancer.
This paper presents the capacitive hyperthermia from physical perspective focusing on the geometr... more This paper presents the capacitive hyperthermia from physical perspective focusing on the geometric dimensions as parameters. For this purpose six parameters having three levels each, including two tunable parameters i.e. applied voltage, frequency together with four geometric parameters i.e. size of the tumor, location of the tumor, electrode size and relative position of the electrodes w.r.t tumor were considered for analysis. Taguchi based design of experiments approach was used for the aforementioned six parameters. Using Taguchi's standard L27 orthogonal array, the required results could be obtained employing least number of experiments. For this study temperature was taken as the quality characteristic to be optimized. Furthermore, analysis of variance (ANOVA) was performed to quantify the effect of each parameter on the response variable and results were presented. To deal with the extent of thermal damage to the healthy tissue and tumor, the fraction of tissue experiencing thermal damage was calculated. For this purpose two indices namely treatment index and damage index were formulated. Finally it was concluded that maximum achieved temperature alone does not depict the effectiveness of the treatment. Rather, the combination of the maximum achieved temperature and accompanied thermal damage to the surrounding healthy tissue which should be considered.
Response to “Comment on 'Stress-density ratio slip-corrected Reynolds equation for u... more Response to “Comment on 'Stress-density ratio slip-corrected Reynolds equation for ultra-thin film gas bearing lubrication' ” [Phys. Fluids [bold 14], 3748 (2002)]. [Physics of Fluids 14, 3749 (2002)]. Eddie Yin-Kwee Ng, Ningyu Liu, Xiaohai Mao. Keywords. ...
School of Electrical Engineering Computer Science Science Engineering Faculty, Nov 1, 2013
ABSTRACT Highly sensitive infrared cameras can produce high-resolution diagnostic images of the t... more ABSTRACT Highly sensitive infrared cameras can produce high-resolution diagnostic images of the temperature and vascular changes of breasts. Wavelet transform based features are suitable in extracting the texture difference information of these images due to their scale-space decomposition. The objective of this study is to investigate the potential of extracted features in differentiating between breast lesions by comparing the two corresponding pectoral regions of two breast thermograms. The pectoral regions of breastsare important because near 50% of all breast cancer is located in this region. In this study, the pectoral region of the left breast is selected. Then the corresponding pectoral region of the right breast is identified. Texture features based on the first and the second sets of statistics are extracted from wavelet decomposed images of the pectoral regions of two breast thermograms. Principal component analysis is used to reduce dimension and an Adaboost classifier to evaluate classification performance. A number of different wavelet features are compared and it is shown that complex non-separable 2D discrete wavelet transform features perform better than their real separable counterparts.
ABSTRACT: In a high density city, given the need to accommodate a fix amount of building volume, ... more ABSTRACT: In a high density city, given the need to accommodate a fix amount of building volume, what can one do to optimise the benefits of the natural (air) environment? The parameters of building density, building heights, and building height differences have ...
Analysis of thermograms have been subjective and hence, resulting in inconsistency in the diagnos... more Analysis of thermograms have been subjective and hence, resulting in inconsistency in the diagnosis of breast diseases by thermography. The aim of this paper is to study the problem of subjective interpretation of breast thermograms and hence using thermography as an adjunct tool for breast cancer diagnosis. It was proposed that the thermograms should be taken within the recommended screening period, classified and analysed in conjunction with an Artificial Neural Network (ANN). Qualitative interpretation of thermal images could be done using active contours algorithm. The 256!200 pixels image can be segmented as one of the inputs to the ANN. As for quantitative analysis of the breast thermograms, first and foremost, the inputs of the ANN should be determined for the successful classification and analysis of the thermograms based on the inputs suggested.
Radiofrequency ablation (RFA) has been increasingly used in treating cancer for multitude of situ... more Radiofrequency ablation (RFA) has been increasingly used in treating cancer for multitude of situations in various tissue types. To perform the therapy safely and reliably, the effect of critical parameters needs to be known beforehand. Temperature plays an important role in the outcome of the therapy and any uncertainties in temperature assessment can be lethal. This study presents the RFA case of fixed tip temperature where we've analysed the effect of electrical conductivity, thermal conductivity and blood perfusion rate of the tumour and surrounding normal tissue on the radiofrequency ablation. Ablation volume was chosen as the characteristic to be optimised and temperature control was achieved via PID controller. The effect of all 6 parameters each having 3 levels was quantified with minimum number of experiments harnessing the fractional factorial characteristic of Taguchi's orthogonal arrays. It was observed that as the blood perfusion increases the ablation volume de...
... CHAPTER 1 The Human Eye Rajendra Acharya, William Tan, Wong Li Yun,Eddie YK Ng, LimChoo Min, ... more ... CHAPTER 1 The Human Eye Rajendra Acharya, William Tan, Wong Li Yun,Eddie YK Ng, LimChoo Min, Caroline Chee, Manjunath Gupta, Jagadish Nayak, and Jasjit S. Suri The eyes are undoubtedly the most sensitive and delicate organs we possess and per-haps the most ...
Multi Modality State-of-the-Art Medical Image Segmentation and Registration Methodologies, 2011
Ocular surface temperature relates deeply with ocular physiology. It is nowadays looked into main... more Ocular surface temperature relates deeply with ocular physiology. It is nowadays looked into mainly by the use of infrared thermography, and occasionally functional infrared imaging. In this study, we recorded ocular thermographic sequences of 60 normal subjects; 30 of them were young and the rest were the elderly. Ocular region in the thermographic sequences was warped to a standardized form, and the eyelashes in each thermographic image were identified and avoided for further analysis. Average horizontal, vertical temperature profiles were unambiguously defined in the warped thermographic sequences. They were extracted, and comparisons were made between the young and the elderly. It was found that the elder subjects exhibited a cooler temperature profile, but their temperature differences between corneal center and limbus were generally higher.
Breast cancer is the second leading cause of death in women. It occurs when cells in the breast b... more Breast cancer is the second leading cause of death in women. It occurs when cells in the breast begin to grow out of control and invade nearby tissues or spread throughout the body. The limitations of mammography as a screening modality, especially in young women with denser breasts, necessitated the development of novel and more effective screening strategies with acceptable sensitivity and specificity. The aim of this study was to develop a feasible interpretive software system which was able to detect and classify breast cancer patients by employing techniques of different analytical software. The protocol described uses 6,000 pieces of thermal data collected from 16-sensors, eight placed on the surface of each breast. Data was collected every 5 min for the duration of the test period. Placement of sensors was accomplished with the use of a template design from information provided by the national tumor registry to insure that the information was collected in areas of the breast where most breast cancers develop. Data in this study was collected from 90 individuals exhibiting four different breast conditions, namely: normal, benign, cancer and suspected-cancer. The temperature data collected from these 16 sensors placed on the surface of each breast were fed as inputs to the classifiers. Comparisons were made on five different kinds of classifiers: back-propagation algorithm, probabilistic neural network, fuzzy (Sugeno-type), Gaussian mixture model and support vector machine. These classifiers were able to attain approximately 80% accuracy in classifying the four different diagnoses (normal, benign, cancer and suspected-cancer). Gaussian mixture model was the most sensitive classifier, achieving the highest sensitivity of 94.8%. Support vector machine was considered the best classifier as it was able to produce the most specific and accurate results. Based on these evaluations, this current effort shows the feasibility of applying analytical software techniques together with the real-time functional thermal analysis to develop a potential tool for the detection and classification of breast cancer.
This paper presents the capacitive hyperthermia from physical perspective focusing on the geometr... more This paper presents the capacitive hyperthermia from physical perspective focusing on the geometric dimensions as parameters. For this purpose six parameters having three levels each, including two tunable parameters i.e. applied voltage, frequency together with four geometric parameters i.e. size of the tumor, location of the tumor, electrode size and relative position of the electrodes w.r.t tumor were considered for analysis. Taguchi based design of experiments approach was used for the aforementioned six parameters. Using Taguchi's standard L27 orthogonal array, the required results could be obtained employing least number of experiments. For this study temperature was taken as the quality characteristic to be optimized. Furthermore, analysis of variance (ANOVA) was performed to quantify the effect of each parameter on the response variable and results were presented. To deal with the extent of thermal damage to the healthy tissue and tumor, the fraction of tissue experiencing thermal damage was calculated. For this purpose two indices namely treatment index and damage index were formulated. Finally it was concluded that maximum achieved temperature alone does not depict the effectiveness of the treatment. Rather, the combination of the maximum achieved temperature and accompanied thermal damage to the surrounding healthy tissue which should be considered.
Response to “Comment on 'Stress-density ratio slip-corrected Reynolds equation for u... more Response to “Comment on 'Stress-density ratio slip-corrected Reynolds equation for ultra-thin film gas bearing lubrication' ” [Phys. Fluids [bold 14], 3748 (2002)]. [Physics of Fluids 14, 3749 (2002)]. Eddie Yin-Kwee Ng, Ningyu Liu, Xiaohai Mao. Keywords. ...
School of Electrical Engineering Computer Science Science Engineering Faculty, Nov 1, 2013
ABSTRACT Highly sensitive infrared cameras can produce high-resolution diagnostic images of the t... more ABSTRACT Highly sensitive infrared cameras can produce high-resolution diagnostic images of the temperature and vascular changes of breasts. Wavelet transform based features are suitable in extracting the texture difference information of these images due to their scale-space decomposition. The objective of this study is to investigate the potential of extracted features in differentiating between breast lesions by comparing the two corresponding pectoral regions of two breast thermograms. The pectoral regions of breastsare important because near 50% of all breast cancer is located in this region. In this study, the pectoral region of the left breast is selected. Then the corresponding pectoral region of the right breast is identified. Texture features based on the first and the second sets of statistics are extracted from wavelet decomposed images of the pectoral regions of two breast thermograms. Principal component analysis is used to reduce dimension and an Adaboost classifier to evaluate classification performance. A number of different wavelet features are compared and it is shown that complex non-separable 2D discrete wavelet transform features perform better than their real separable counterparts.
ABSTRACT: In a high density city, given the need to accommodate a fix amount of building volume, ... more ABSTRACT: In a high density city, given the need to accommodate a fix amount of building volume, what can one do to optimise the benefits of the natural (air) environment? The parameters of building density, building heights, and building height differences have ...
Analysis of thermograms have been subjective and hence, resulting in inconsistency in the diagnos... more Analysis of thermograms have been subjective and hence, resulting in inconsistency in the diagnosis of breast diseases by thermography. The aim of this paper is to study the problem of subjective interpretation of breast thermograms and hence using thermography as an adjunct tool for breast cancer diagnosis. It was proposed that the thermograms should be taken within the recommended screening period, classified and analysed in conjunction with an Artificial Neural Network (ANN). Qualitative interpretation of thermal images could be done using active contours algorithm. The 256!200 pixels image can be segmented as one of the inputs to the ANN. As for quantitative analysis of the breast thermograms, first and foremost, the inputs of the ANN should be determined for the successful classification and analysis of the thermograms based on the inputs suggested.
Radiofrequency ablation (RFA) has been increasingly used in treating cancer for multitude of situ... more Radiofrequency ablation (RFA) has been increasingly used in treating cancer for multitude of situations in various tissue types. To perform the therapy safely and reliably, the effect of critical parameters needs to be known beforehand. Temperature plays an important role in the outcome of the therapy and any uncertainties in temperature assessment can be lethal. This study presents the RFA case of fixed tip temperature where we've analysed the effect of electrical conductivity, thermal conductivity and blood perfusion rate of the tumour and surrounding normal tissue on the radiofrequency ablation. Ablation volume was chosen as the characteristic to be optimised and temperature control was achieved via PID controller. The effect of all 6 parameters each having 3 levels was quantified with minimum number of experiments harnessing the fractional factorial characteristic of Taguchi's orthogonal arrays. It was observed that as the blood perfusion increases the ablation volume de...
... CHAPTER 1 The Human Eye Rajendra Acharya, William Tan, Wong Li Yun,Eddie YK Ng, LimChoo Min, ... more ... CHAPTER 1 The Human Eye Rajendra Acharya, William Tan, Wong Li Yun,Eddie YK Ng, LimChoo Min, Caroline Chee, Manjunath Gupta, Jagadish Nayak, and Jasjit S. Suri The eyes are undoubtedly the most sensitive and delicate organs we possess and per-haps the most ...
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