As a hybrid imaging modality that combines optical excitation with acoustic detection,photoacoustic tomography(PAT)has become one of the fastest growing biomedical imaging modalities.Among various types of transducer ...As a hybrid imaging modality that combines optical excitation with acoustic detection,photoacoustic tomography(PAT)has become one of the fastest growing biomedical imaging modalities.Among various types of transducer arrays used in a PAT system conguration,the linear array is the most commonly utilized due to its convenience and low-cost.Although linear array-based PAT has been quickly developed within the recent decade,there are still two major challenges that impair the overall performance of the PAT imaging system.Therst challenge is that the three-dimensional(3D)imaging capability of a linear array is limited due to its poor elevational resolution.The other challenge is that the geometrical shape of the linear array constrains light illumination.To date,substantial e®orts have been made to address the aforementioned challenges.This review will present current technologies for improving the elevation resolution and light delivery of linear array-based PAT systems.展开更多
Spinal deformities assessment using 3D ultrasound scanning has limitations in fitting onto different back surface contour as well as fitting within the gaps between subject and their spinal brace during bracing assess...Spinal deformities assessment using 3D ultrasound scanning has limitations in fitting onto different back surface contour as well as fitting within the gaps between subject and their spinal brace during bracing assessments.The study proposed a flexible array ultrasound transducer to overcome these limitations.The results demonstrated the feasibility of spinal deformity assessments with a flexible ultrasound array when arranged in four shapes,namely Linear,Concave,Convex,and S-shaped.For comparisons of imaging performance on spinous process using the four shapes,Convex and S-shaped transducer showed a depth dependence and lateral location dependence of the lateral intensity distribution of spinous process,respectively.S-shaped transducer had the least accurate prediction of the location of spinous process,with measurement error of 4.83.2 mm,it also showed poorer prediction on spinal curvature measurements.This is suggested to be due to the asymmetrical distortion to the spinous process due to the lateral location dependence of the image.However,the coronal curve prediction of spine phantom performed well with R-squared values of>0.97 in all transducer shapes.The results of this study paved the way for further investigation on the improvement of image quality and measurement accuracy under different shapes for the flexible array,mechanism of dynamic shape change during the scanning to fit different body contour,as well as extension from 1D to 2D flexible array.展开更多
基金supported in part by the Career Catalyst Research Grant from the Susan G.Komen Foundation(No.CCR17481211).
文摘As a hybrid imaging modality that combines optical excitation with acoustic detection,photoacoustic tomography(PAT)has become one of the fastest growing biomedical imaging modalities.Among various types of transducer arrays used in a PAT system conguration,the linear array is the most commonly utilized due to its convenience and low-cost.Although linear array-based PAT has been quickly developed within the recent decade,there are still two major challenges that impair the overall performance of the PAT imaging system.Therst challenge is that the three-dimensional(3D)imaging capability of a linear array is limited due to its poor elevational resolution.The other challenge is that the geometrical shape of the linear array constrains light illumination.To date,substantial e®orts have been made to address the aforementioned challenges.This review will present current technologies for improving the elevation resolution and light delivery of linear array-based PAT systems.
基金This work was supported by Hong Kong Research Grant Council(152220/14E,R5017-18),Hong Kong PhD Fellowship Scheme,and the Hong Kong Polytechnic University.
文摘Spinal deformities assessment using 3D ultrasound scanning has limitations in fitting onto different back surface contour as well as fitting within the gaps between subject and their spinal brace during bracing assessments.The study proposed a flexible array ultrasound transducer to overcome these limitations.The results demonstrated the feasibility of spinal deformity assessments with a flexible ultrasound array when arranged in four shapes,namely Linear,Concave,Convex,and S-shaped.For comparisons of imaging performance on spinous process using the four shapes,Convex and S-shaped transducer showed a depth dependence and lateral location dependence of the lateral intensity distribution of spinous process,respectively.S-shaped transducer had the least accurate prediction of the location of spinous process,with measurement error of 4.83.2 mm,it also showed poorer prediction on spinal curvature measurements.This is suggested to be due to the asymmetrical distortion to the spinous process due to the lateral location dependence of the image.However,the coronal curve prediction of spine phantom performed well with R-squared values of>0.97 in all transducer shapes.The results of this study paved the way for further investigation on the improvement of image quality and measurement accuracy under different shapes for the flexible array,mechanism of dynamic shape change during the scanning to fit different body contour,as well as extension from 1D to 2D flexible array.
