Article
Biochemical Research Methods
Anjali Thomas, Souradip Paul, Mayanglambam Suheshkumar Singh
Summary: We report an adaptive energy-compensated synthetic aperture focusing technique (eC-SAFT) for improving the imaging performance of photoacoustic microscopy (PAM). Experimental validation studies show that the proposed technique outperforms conventional methods in terms of axial resolution, lateral resolution, SNR, and contrast.
JOURNAL OF BIOPHOTONICS
(2023)
Article
Acoustics
Philip M. Holmes, Hyoung-Ki Lee, Matthew W. Urban
Summary: The choices of transmit and receive f-numbers have an impact on ultrasound image contrast and spatial resolution. This study investigates the effects of varying f-numbers on DAS and DMAS reconstructed SA images, measuring parameters such as MSER, gCNR, and spatial resolution. The findings provide insights into the behavior of the reconstruction algorithms and can guide f-number selection.
Article
Engineering, Electrical & Electronic
Anjali Thomas, Souradip Paul, Sufayan Mulani, Mayanglambam Suheshkumar Singh
Summary: We propose an adaptive interference-corrected synthetic aperture focusing technique (IntC-SAFT) for improving the imaging performance of photoacoustic microscopy (PAM). Our algorithm incorporates the interference effect in SAFT, taking into account the coupling effect while summing up interfering (PA) waves. Experimental validation studies show that our IntC-SAFT outperforms conventional SAFT in terms of SNR, contrast ratio, axial resolution, and lateral resolution.
IEEE SENSORS LETTERS
(2023)
Article
Biochemical Research Methods
Soheil Hakakzadeh, Mohammadreza Amjadian, Yachao Zhang, Seyed Masood Mostafavi, Zahra Kavehvash, Lidai Wang
Summary: In a photoacoustic imaging system, limitations in detector bandwidth result in unwanted ripples in the signals, degrading resolution and contrast and producing artifacts in reconstructed images along the axial direction. To address this, a signal restoration algorithm is proposed which uses a mask to extract signals at absorber positions and remove unwanted ripples. The restoration improves axial resolution and contrast in reconstructed images.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Acoustics
Chen-Yin Ni, Chu Chen, Kai-Ning Ying, Lu-Nan Dai, Ling Yuan, Wei-Wei Kan, Zhong-Hua Shen
Summary: The LU-based F-SAFT algorithm is developed to visualize horizontal hole-type defects in aluminum. By incorporating optimizations such as velocity mapping and frequency range selection, small defects can be visualized in 3D with improved image quality and reconstruction speed. The wide-band generation characteristic of the LU technique allows for a higher Signal-to-Noise Ratio in the acoustic wave signals.
Article
Acoustics
Da Teng, Lishuai Liu, Yanxun Xiang, Fu-Zhen Xuan
Summary: This study combines the improved DMAS beamforming method with traditional synthetic focusing to optimize TFM imaging performance. The optimized TFM imaging results show significant improvements in SNR and lateral spatial resolution, providing a promising solution for post-processing of ultrasonic phased array with improved imaging performance.
Article
Acoustics
Sajjad Afrakhteh, Hamid Behnam
Summary: The paper introduces a novel random synthetic transmit aperture (RSTA) method, which increases the data acquisition rate by randomly selecting a portion of linear array elements in the transmit mode and applying tensor completion (TC) to enhance image quality. The proposed method reduces data acquisition time significantly and has shown promising results in experiments.
Article
Chemistry, Analytical
Yanjie Zhang, Tianyou Li, Hongkai Chen, Zhihui Xu, Xinyao Li, Wangzhe Du, Yaxing Liu
Summary: This paper proposes a noncontact internal defect imaging method for cylindrical components and establishes an automatic photoacoustic testing platform. The proposed method utilizes a synthetic aperture focusing technology based on laser ultrasonic and analyzes the relationship between imaging quality and position of discrete points. The validity of the method is verified through testing small holes in an aluminum alloy rod. The results show high accuracy in presenting the outline of the small hole, with circumferential resolution less than 1° and dimensional accuracy and position error less than 0.1 mm.
Article
Acoustics
Kai-Ning Ying, Chen-Yin Ni, Lu-Nan Dai, Ling Yuan, Wei-Wei Kan, Zhong-Hua Shen
Summary: This paper proposes a Multi-mode Time-domain SAFT (MMT-SAFT) algorithm for laser ultrasonic defect imaging. By imaging with multiple LU modes, the algorithm reduces artifacts and improves image quality. The proposed technique contributes to the development of laser ultrasonic defect imaging.
Article
Chemistry, Analytical
Yang Wu, Wendong Zhang, Xingling Shao, Yuhua Yang, Tian Zhang, Miao Lei, Zhihao Wang, Bizhen Gao, Shumin Hu
Summary: This paper applies the multi-element synthetic aperture focusing (M-SAF) to the ring array of breast ultrasonography (US) imaging, addressing the issue of low imaging quality. The optimal sub-aperture size is determined to be four elements, as verified by simulations and experiments.
Article
Engineering, Biomedical
Changhan Yoon, Jeeun Kang, Tai-Kyong Song, Jin Ho Chang
Summary: This paper presents a method for three-dimensional photoacoustic image reconstruction using a commercial one-dimensional array transducer. By applying synthetic aperture focusing (SAF) technique, the elevational resolution is improved, and the effectiveness of the method is demonstrated through simulation and experiments.
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING
(2022)
Article
Materials Science, Characterization & Testing
Lu-Nan Dai, Chen-Yin Ni, Kai-Ning Ying, Ling Yuan, Zhi Yang, Wei-Wei Kan, Zhong-Hua Shen
Summary: A laser ultrasonics based frequency domain synthetic aperture focusing technology has been developed for imaging internal horizontal hole defects in bimetallic composites with a diameter of approximately 1.0 mm. The results show that this technology can improve imaging quality and locating capability, with a low testing error.
NDT & E INTERNATIONAL
(2024)
Article
Chemistry, Analytical
Taeil Yoon, Younggue Kim, Muhammad Awais, Byeongha Lee
Summary: This study presents a method to enhance laser ultrasound (LUS) image reconstruction by extracting the acoustic velocity in situ with curve fitting using the time-domain synthetic aperture focusing technique (T-SAFT). The operational principle is demonstrated through numerical simulation and experimental confirmation. The results show that the all-optic LUS system can successfully reconstruct needle-like objects embedded within polydimethylsiloxane (PDMS) blocks and chicken breasts by extracting the in situ acoustic velocity. The study emphasizes the importance of knowing the acoustic velocity in the T-SAFT process for accurate depth location and high resolution imaging.
Article
Engineering, Biomedical
Asraf Mohamed Moubark, Zainab Alomari, Mohd Hairi Mohd Zaman, Mohd Asyraf Zulkifley, Sawal Hamid Md Ali, Luzhen Nie, Steven Freear
Summary: The study evaluated the performance of FDMAS by fine-tuning Delta x to find its optimal value and improve boundary definition when BSAC segmentation was applied in ultrafast imaging. Results showed improvements in lateral resolution and image contrast ratio with reduced Delta x, offering a means to enhance boundary definition on B-mode images.
BIOMEDICAL SIGNAL PROCESSING AND CONTROL
(2022)
Article
Acoustics
Che-Chou Shen, You-An Chen, Hsin-Yu Ku
Summary: High-intensity focused ultrasound (HIFU) is a non-invasive treatment method with various applications. Passive acoustic mapping (PAM) is used to monitor HIFU-induced cavitation events, but conventional methods have limitations. In this study, a new adaptive PAM method called DMAS-VA is proposed to overcome these limitations and improve image resolution and contrast.
Review
Chemistry, Multidisciplinary
Wonseok Choi, Byullee Park, Seongwook Choi, Donghyeon Oh, Jongbeom Kim, Chulhong Kim
Summary: Photoacoustic imaging (PAI) has been investigated for decades as a niche biomedical imaging modality. Despite its desirable contrast and resolution, PAI faces limitations such as low signal-to-noise ratio, diminished image contrast, and spatial resolution constraints in deep tissue. Practical limitations, including insufficient targeting and difficulties in developing clinically translatable agents, have also been identified. This review discusses recent research efforts in addressing these challenges and proposes future directions for contrast-enhanced PAI.
Article
Optics
Wangyu Kim, Wonseok Choi, Joongho Ahn, Changyeop Lee, Chulhong Kim
Summary: In this study, a dual-modal PA and US imaging system using a 2D matrix transducer array and a motorized 2D scanning system was demonstrated. The system enlarged the field-of-view of volumetric images by merging multiple PA volumes to form a wide-field image. In vivo imaging of rat sentinel lymph nodes and bladders stained with methylene blue was achieved. The technique has the potential for real-time monitoring and wide-field imaging in various preclinical and clinical studies.
Article
Biochemical Research Methods
Jinhee Yoo, Donghyeon Oh, Chulhong Kim, Hyung Ham Kim, Ji-Yong Um
Summary: Photoacoustic (PA) imaging is a high-fidelity biomedical imaging technique that utilizes molecular-specific optical absorption in biological tissue. By introducing a switchable preamplifier, the signal-to-noise ratio (SNR) of PA imaging can be selectively enhanced, allowing for better visualization of deep tissues. This study demonstrates the application of the preamplifier in in vivo whole-body PA/US imaging, showing improved SNR and revealing deeply located organs and vascular networks. The switchable amplifier strengthens the mutual complement between PA/US imaging and can potentially address the imbalance in image depth between the two modalities.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Chemistry, Multidisciplinary
Seongwook Choi, Jinge Yang, Soo Young Lee, Jiwoong Kim, Jihye Lee, Won Jong Kim, Seungchul Lee, Chulhong Kim
Summary: This study demonstrates a deep learning-based approach to reduce limited-view artifacts and improve image quality and temporal resolution in photoacoustic computed tomography (PACT). The approach, called DL-PACT, enables high-quality imaging in a fast and cost-effective manner, which is significant for various clinical applications such as neurology, cardiology, pharmacology, endocrinology, and oncology.
Article
Engineering, Biomedical
Taejeong Kim, Hyun Jin Kim, Wonseok Choi, Yeong Mi Lee, Jung Hyun Pyo, Junseok Lee, Jeesu Kim, Jihoon Kim, Joung-Hun Kim, Chulhong Kim, Won Jong Kim
Summary: Deep brain stimulation through implanted electrodes is effective for neuronal disorders, but limited by side effects. This study demonstrates that systemically administered piezoelectric nanoparticles, activated by high-intensity focused ultrasound, can stimulate deep brain tissue without direct brain electrode insertion. The nanoparticles temporarily disrupt the blood-brain barrier and stimulate dopamine release, effectively alleviating symptoms in a Parkinson's disease mouse model. This strategy has potential for developing minimally invasive therapies for neurodegenerative diseases.
NATURE BIOMEDICAL ENGINEERING
(2023)
Article
Chemistry, Analytical
Chiho Yoon, Changyeop Lee, Keecheol Shin, Chulhong Kim
Summary: This paper presents a new motion compensation method for removing motion artifacts in photoacoustic imaging, and its effectiveness is verified through experiments. This method has significant implications for clinical applications of photoacoustic imaging.
Review
Chemistry, Multidisciplinary
Seongyi Han, Tsedendamba Ninjbadgar, Mijeong Kang, Chulhong Kim, Jeesu Kim
Summary: Photoacoustic agents have wide applications in theranostic field. By evaluating the biodistribution obtained from photoacoustic images, the efficiency and response of theranostic agents can be analyzed. This study summarizes the recent advances in photoacoustic-guided phototherapy, providing guidance for future development of theranostic agents. With the recent applications of photoacoustic imaging in clinical trials, theranostic agents with photoacoustic monitoring have potential for clinical translation.
Article
Acoustics
Joongho Ahn, Jin Woo Baik, Donggyu Kim, Karam Choi, Seunghyun Lee, Sung-Min Park, Jin Young Kim, Sung Hyun Nam, Chulhong Kim
Summary: Postprandial hyperglycemia induces endothelial dysfunction, leading to increased cardiovascular risks. This study demonstrates the use of photoacoustic microscopy to noninvasively monitor morphological changes in blood vessels during acute hyperglycemia. The results show that acute hyperglycemia causes transient vasoconstriction in arterioles, with an opposite trend of change in blood glucose. These findings provide insights into vascular glucose homeostasis and the relationship between diabetes and cardiovascular diseases.
Article
Acoustics
Changyeop Lee, Seonghee Cho, Donghyun Lee, Jonghun Lee, Jong-Il Park, Hong-Ju Kim, Sae Hyun Park, Wonseok Choi, Ung Kim, Chulhong Kim
Summary: This study proposes a panoramic volumetric clinical photoacoustic and ultrasound imaging system for imaging vascular networks and measuring hemoglobin oxygen saturation levels. The system achieves large field-of-view imaging through multiple photoacoustic and ultrasound scans, which are mosaic-stitched after correction. The findings of this study have important implications for various clinical fields such as cardiovascular imaging, dermatology, vascular surgery, internal medicine, and oncology.
Review
Nanoscience & Nanotechnology
Byullee Park, Donghyeon Oh, Jeesu Kim, Chulhong Kim
Summary: Functional photoacoustic imaging is a promising biological imaging technique that provides scalable resolution, imaging depth, and functional information. It can capture super-resolution images at the nanoscale and measure various physiological parameters at the microscopic and macroscopic scales. This comprehensive review discusses recent advances in technology and applications, and explores the future prospects of functional photoacoustic imaging in the biomedical field.
Review
Medicine, Research & Experimental
Haeni Lee, Wonseok Choi, Chulhong Kim, Byullee Park, Jeesu Kim
Summary: Photoacoustic imaging has been developed as a new biomedical molecular imaging modality and has been combined with ultrasound imaging to visualize physiological and morphological information in biological systems. Dual-modal photoacoustic and ultrasound imaging showed synergistic advances in photoacoustic imaging with the guidance of ultrasound images. This review presents the recent progresses in dual-modal photoacoustic and ultrasound imaging systems at various study scales and summarizes different strategies for combining ultrasound structural information with photoacoustic molecular information.
EXPERIMENTAL BIOLOGY AND MEDICINE
(2023)
Article
Computer Science, Artificial Intelligence
Chiho Yoon, Sampa Misra, Kwang-Ju Kim, Chulhong Kim, Bum Joon Kim
Summary: In this study, a deep learning method was used to classify patients requiring EVT within 6 hours. A DL-based segmentation model was developed to predict the ROI from multi-modal MR images, and radiomic and deep features were extracted. The results showed that combining radiomic and deep features improved the classification performance, with an F0.5 score of 80.6% achieved in classifying SOT within 6 hours. The DL model using multi-modal MR images has the potential to become a practical decision-support tool for stroke treatments.
EXPERT SYSTEMS WITH APPLICATIONS
(2023)
Review
Chemistry, Analytical
Changyeop Lee, Chulhong Kim, Byullee Park
Summary: Photoacoustic imaging is a non-invasive biomedical imaging technique that combines optics and acoustics. This review focuses on the emergence of three-dimensional handheld PA imaging systems and their potential applications in the biomedical field. The review provides an overview of different imaging techniques and discusses potential solutions for system limitations.
Article
Chemistry, Multidisciplinary
Hyori Lee, Byullee Park, Jihye Lee, Yeoul Kang, Moongyu Han, Junseok Lee, Chulhong Kim, Won Jong Kim
Summary: This study designs a charge-convertible nanomedicine that facilitates deep penetration into solid tumors via transcytosis, providing a versatile theragnosis platform for noninvasive photoacoustic imaging and high therapeutic efficiency. The nanomedicine is an albumin-based calcium phosphate nanomedicine loaded with IR820 for high-resolution photoacoustic imaging and enhanced photothermal therapy. The pH-triggered transcytosis of the nanomedicine enabled by caveolae-mediated endocytosis and calcium ion-induced exocytosis is demonstrated in cellular, spheroid, and in vivo tumor models.
Article
Chemistry, Multidisciplinary
Donghyeon Oh, Donghyun Lee, Jinseok Heo, Jooyoung Kweon, Uijung Yong, Jinah Jang, Yong Joo Ahn, Chulhong Kim
Summary: A new non-invasive imaging system has been developed to assess renal microcirculation. The system allows researchers to observe the entire 3D vascular network in a living rat's kidney at a high resolution without using any contrast agent. By monitoring the kidneys with acute kidney injury and diabetic kidney disease, hemodynamic and morphological changes can be quantitatively measured. This study provides valuable insights for future research in diabetes and kidney transplantation.
