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Tian R, Wang Q, Li S, Nong X. Non-invasive efficacy assessment of pulsed dye laser and photodynamic therapy for port-wine stain. Indian J Dermatol Venereol Leprol 2024; 90:615-622. [PMID: 38841964 DOI: 10.25259/ijdvl_985_2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 12/28/2023] [Indexed: 06/07/2024]
Abstract
Port wine stain (PWS) is a congenital vascular malformation that commonly occurs on the face and neck. Currently, the main treatments for port wine stain are pulsed dye laser (PDL) and photodynamic therapy (PDT). However, the efficacy evaluation of PWS mostly relies on the subjective judgement of clinicians, and it is difficult to accurately respond to many small changes after treatment. Therefore, some non-invasive and efficient efficacy assessment methods are also needed. With the continuous development of technology, there are currently many visualisation instruments to evaluate PWS, including dermoscopy, VISIA-CR™ system, reflectance confocal microscopy (RCM), high-frequency ultrasound (HFUS), optical coherence tomography (OCT), Photoacoustic imaging (PAI), laser speckle imaging (LSI) and laser Doppler imaging (LDI). Among them, there are simple and low-cost technologies such as dermoscopy and the VISIA-CR™ system, but they may not be able to observe the deeper structures of PWS. At this time, combining techniques such as HFUS and OCT to increase penetration depth is crucial to evaluate PWS. In the future, the combination of these different technologies could help overcome the limitations of a single technology. This article provides a systematic overview of non-invasive methods for evaluating treatment efficacy in port wine stains and summarises their advantages and disadvantages.
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Affiliation(s)
- Rongqian Tian
- Department of Dermatology, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Qin Wang
- Department of Dermatology, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Sijin Li
- Department of Dermatology, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Xiang Nong
- Department of Dermatology, First Affiliated Hospital of Kunming Medical University, Kunming, China
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Wang M, Singh R, Zhang W, Orringer JS, Paulus YM, Yang X, Wang X. Cutaneous Hypervascularization Treatment Using Photo-Mediated Ultrasound Therapy. JID INNOVATIONS 2023; 3:100237. [PMID: 38024557 PMCID: PMC10661455 DOI: 10.1016/j.xjidi.2023.100237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 12/01/2023] Open
Abstract
Photo-mediated ultrasound therapy (PUT) is a cavitation-based, highly selective antivascular technique. In this study, the effectiveness and safety of PUT on cutaneous vascular malformation was examined through in vivo experiments in a clinically relevant chicken wattle model, whose microanatomy is similar to that of port-wine stain and other hypervascular dermal diseases in humans. Assessed by optical coherence tomography angiography, the blood vessel density in the chicken wattle decreased by 73.23% after one session of PUT treatment in which 0.707 J/cm2 fluence laser pulses were applied concurrently with ultrasound bursts (n = 7, P < .01). The effectiveness of removing blood vessels in the skin at depth up to 1 mm was further assessed by H&E-stained histology at multiple time points, which included days 1, 3, 7, 14, and 21 after treatment. Additional immunohistochemical analyses with CD31, caspase-3, and Masson's trichrome stains were performed on day 3 after treatment. The results show that the PUT-induced therapeutic effect was confined and specific to blood vessels only, whereas unwanted collateral damage in other skin tissues such as collagen was avoided. The findings from this study demonstrate that PUT can efficiently and safely remove hypervascular dermal capillaries using laser fluence at a level that is orders of magnitude smaller than that used in conventional laser treatment of vascular lesions, thus offering a safer alternative technique for clinical management of cutaneous vascular malformations.
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Affiliation(s)
- Mingyang Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Rohit Singh
- PhotoSonoX LLC, Ann Arbor, Michigan, USA
- Institute for Bioengineering Research, University of Kansas, Lawrence, Kansas, USA
- Department of Mechanical Engineering, School of Engineering, University of Kansas, Lawrence, Kansas, USA
| | - Wei Zhang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Yannis M. Paulus
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Xinmai Yang
- Institute for Bioengineering Research, University of Kansas, Lawrence, Kansas, USA
- Department of Mechanical Engineering, School of Engineering, University of Kansas, Lawrence, Kansas, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
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Linkous C, Pagan AD, Shope C, Andrews L, Snyder A, Ye T, Valdebran M. Applications of Laser Speckle Contrast Imaging Technology in Dermatology. JID INNOVATIONS 2023; 3:100187. [PMID: 37564105 PMCID: PMC10410171 DOI: 10.1016/j.xjidi.2023.100187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 12/22/2022] [Accepted: 12/27/2022] [Indexed: 01/26/2023] Open
Abstract
Laser speckle contrast imaging or laser speckle imaging (LSI) is a noninvasive imaging technology that can detect areas of dynamic perfusion or vascular flow. Thus, LSI has shown increasing diagnostic utility in various pathologies and has been employed for intraoperative, postoperative, and long-term monitoring in many medical specialties. Recently, LSI has gained traction in clinical dermatology because it can be effective in the assessment of pathologies that are associated with increased perfusion and hypervascularity compared with that of normal tissue. To date, LSI has been found to be highly accurate in monitoring skin graft reperfusion, determining the severity of burns, evaluating neurosurgical revascularization, assessing persistent perfusion in capillary malformations after laser therapy, and differentiating malignant and benign skin lesions. LSI affords the advantage of noninvasively assessing lesions before more invasive methods of diagnosis, such as tissue biopsy, while remaining inexpensive and exhibiting no adverse events to date. However, potential obstacles to its clinical use include tissue movement artifact, primarily qualitative data, and unclear impact on clinical practice given the lack of superiority data compared with the current standard-of-care diagnostic methods. In this review, we discuss the clinical applications of LSI in dermatology for use in the diagnosis and monitoring of vascular, neoplastic, and inflammatory skin conditions.
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Affiliation(s)
- Courtney Linkous
- College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Angel D. Pagan
- School of Medicine, Ponce Health Sciences University, Ponce, Puerto Rico, USA
| | - Chelsea Shope
- College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Laura Andrews
- College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Alan Snyder
- Department of Dermatology & Dermatologic Surgery, College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Tong Ye
- Department of Bioengineering, Clemson University, Clemson, South Carolina, USA
- Department of Regenerative Medicine & Cell Biology, College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Manuel Valdebran
- Department of Dermatology & Dermatologic Surgery, College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
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Kubelick KP, Mehrmohammadi M. Magnetic particles in motion: magneto-motive imaging and sensing. Theranostics 2022; 12:1783-1799. [PMID: 35198073 PMCID: PMC8825589 DOI: 10.7150/thno.54056] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 11/22/2021] [Indexed: 11/05/2022] Open
Abstract
Superparamagnetic nanoparticles have become an important tool in biomedicine. Their biocompatibility, controllable small size, and magnetic properties allow manipulation with an external magnetic field for a variety of diagnostic and therapeutic applications. Recently, the magnetically-induced motion of superparamagnetic nanoparticles has been investigated as a new source of imaging contrast. In magneto-motive imaging, an external, time-varying magnetic field is applied to move a magnetically labeled subject, such as labeled cells or tissue. Several major imaging modalities such as ultrasound, photoacoustic imaging, optical coherence tomography, and laser speckle tracking can utilize magneto-motive contrast to monitor biological events at smaller scales with enhanced contrast and sensitivity. In this review article, an overview of magneto-motive imaging techniques is presented, including synthesis of superparamagnetic nanoparticles, fundamental principles of magneto-motive force and its utility to excite labeled tissue within a viscoelastic medium, current capabilities of magneto-motive imaging modalities, and a discussion of the challenges and future outlook in the magneto-motive imaging domain.
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Affiliation(s)
- Kelsey P. Kubelick
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Georgia, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Georgia, USA
| | - Mohammad Mehrmohammadi
- Department of Biomedical Engineering, Wayne State University, Michigan, USA
- Barbara Ann Karmanos Cancer Institute, Michigan, USA
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Laser Speckle Contrast Imaging for the Objective Assessment of Blood Perfusion in Keloids Treated With Dual-Wavelength Laser Therapy. Dermatol Surg 2021; 47:e117-e121. [PMID: 33795568 DOI: 10.1097/dss.0000000000002836] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Most of the widely used methods for the assessment of keloid treatment are subjective grading scales based on the opinion of an individual clinician or patient. There is a growing need for objective methods to evaluate keloid treatment. OBJECTIVE This study aimed to evaluate the value of laser speckle contrast imaging (LSCI) as an objective method for the assessment of dual-wavelength laser therapy for keloids. METHODS This prospective study included 21 patients with 54 keloids. All patients were treated with a combined 585-nm pulsed dye laser and 1,064 nm neodymium-doped yttrium aluminum garnet dual-wavelength laser at 4 weeks to 6 weeks intervals. Keloids were assessed using the Vancouver Scar Scale (VSS) and LSCI. RESULTS The total VSS score significantly decreased after 4 sessions of treatment (p < .05). Blood perfusion in keloids as measured by LSCI was significantly reduced after treatment (p < .05). The improvement of chest keloids in terms of the total VSS score and blood perfusion was significantly greater than that of scapular keloids (p < .05). There was a positive correlation between decreased perfusion and reduced total VSS score (R2 = 0.84). CONCLUSION Blood perfusion in keloids significantly decreased after dual-wavelength laser therapy. Laser speckle contrast imaging is a promising objective method for assessing the improvement of keloids treated with laser therapy.
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Noormohammadpour P, Ehsani AH, Mahmoudi H, Balighi K, Razavi Z. Does Double-Pass Pulsed-Dye Laser With Long and Short Pulse Duration Increase Treatment Efficacy of Port-Wine Stain? A Randomized Clinical Trial. Dermatol Surg 2021; 47:e122-e126. [PMID: 33795569 DOI: 10.1097/dss.0000000000002819] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Although pulsed-dye laser (PDL) 595 nm is known as the gold standard for treatment of port-wine stains (PWS), complete clearance of lesions occurs in a minority of cases. OBJECTIVE To compare the efficacy and safety of double-pass pulsed-dye laser (DPL), long pulse duration (20 m/s) followed by short pulse duration (1.5 m/s) within 20 minutes interval, with single-pass pulsed-dye laser (SPL) for (1.5 m/s) in the treatment of PWS. METHODS Twenty-four patients with PWS underwent 3 sessions of PDL. Each lesion was randomly divided into 2 portions to receive DPL or SPL. Colorimetric and dermoscopic evaluations were used to determine the response objectively. In addition, improvement was scored subjectively using the visual analog scale (VAS). RESULTS According to colorimetric analysis, the mean blanching rates for DPL and SPL treated sites were 48% (SD = 0.215) and 37% (SD = 0.213), respectively (p = .001). With VAS, 3.79 (SD = 0.93) and 3.33 (SD = 0.91) improvement scores were reported in the DPL and SPL treated areas, respectively (p = .008). Dermoscopic images showed that larger deep vessels were the most common remnant vessels in both treatment areas. CONCLUSION Compared with SPL, DPL with 20 minutes interval seems to be a more effective and safe method for the treatment of PWS.
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Affiliation(s)
- Pedram Noormohammadpour
- All authors are affiliated with the Department of Dermatology, Razi Hospital, Tehran University of Medical Science, Tehran, Iran
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Buch J, Karagaiah P, Raviprakash P, Patil A, Kroumpouzos G, Kassir M, Goldust M. Noninvasive diagnostic techniques of port wine stain. J Cosmet Dermatol 2021; 20:2006-2014. [PMID: 33788368 DOI: 10.1111/jocd.14087] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/09/2021] [Accepted: 03/16/2021] [Indexed: 12/29/2022]
Abstract
Port-wine stain (PWS) is a benign capillary malformation that most commonly occurs in the head and neck. It is present at birth and progresses over time. It is formed by progressive dilatation of post-capillary venules and is associated with hypertrophy and nodularity with increasing age, leading to cosmetic disfigurement and psychological aggravation. It is caused by genetic mosaicism in GNAQ and GNA11 genes. Histopathology is the gold standard for assessment of PWS but it is invasive and may cause scarring. Inadequate characterization of the lesions may predispose to inadequate treatment protocols as well as higher treatment dosages. Clinical evaluation of treatment efficacy is subjective and may not be a representative of actual results. Therefore, an objective visualization modality is required. With evolving technology, numerous optical instruments have been developed for objective evaluation and visualization of subsurface structures. These include VISIA-CR™ system, videodermoscopy, high-frequency ultrasound (HFUS), laser speckle contrast imaging (LSCI), reflectance spectrophotometers and tristimulus colorimeter, laser Doppler flowmetry (LDF), cross-polarized diffuse reflectance imaging system (CDR), reflectance confocal microscopy (RCM), optical coherence tomography (OCT), and spatial frequency domain imaging (SFDI). These semi-quantitative modes of diagnosis are complementary to each other. Some can be used in the clinical setting while others, due to high instrument cost, are limited to the research settings. In this review, we bring to you a brief overview of noninvasive diagnostic modalities in PWS.
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Affiliation(s)
- Jeta Buch
- Private Practitioner, Ahmedabad, India
| | - Priyanka Karagaiah
- Department of Dermatology, Bangalore Medical College and Research Institute, Bangalore, India
| | | | - Anant Patil
- Department of Pharmacology, Dr. DY Patil Medical College, Navi Mumbai, India
| | - George Kroumpouzos
- Department of Dermatology, Alpert Medical School of Brown University, Providence, RI, USA.,Department of Dermatology, Medical School of Jundiaí, São Paulo, Brazil.,GK Dermatology, PC, South Weymouth, MA, USA
| | | | - Mohamad Goldust
- Department of Dermatology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
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Abstract
Hemangioma is a congenital vascular soft tissue tumor, defined as a vascular lesion present in the newborn, with a progressive developmental pattern related to age. It has a progressive and regressive periodic growth mode, in comparison with arteriovenous malformation (AVM). Although there are many treatment approaches for curing this lesion such as; surgery, cryotherapy, sclerosant agents, laser therapy has more advantages in comparison to the other methods. Such as, hemostasis and clean operating field, decreased amount of pain and edema. There are many types of lasers manufactured that could be used for therapeutic purposes. This article focuses on different types of laser applications in the treatment of these lesions.
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Affiliation(s)
- Ehsan Azma
- Oral and Maxillofacial Medicine of Dental Faculty of Guilan Medical University, Guilan, Iran
| | - Melika Razaghi
- Laser Application in Medical Sciences Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Regan C, Hayakawa C, Choi B. Momentum transfer Monte Carlo for the simulation of laser speckle imaging and its application in the skin. BIOMEDICAL OPTICS EXPRESS 2017; 8:5708-5723. [PMID: 29296499 PMCID: PMC5745114 DOI: 10.1364/boe.8.005708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/15/2017] [Accepted: 10/18/2017] [Indexed: 05/03/2023]
Abstract
Due to its simplicity and low cost, laser speckle imaging (LSI) has achieved widespread use in biomedical applications. However, interpretation of the blood-flow maps remains ambiguous, as LSI enables only limited visualization of vasculature below scattering layers such as the epidermis and skull. Here, we describe a computational model that enables flexible in-silico study of the impact of these factors on LSI measurements. The model uses Monte Carlo methods to simulate light and momentum transport in a heterogeneous tissue geometry. The virtual detectors of the model track several important characteristics of light. This model enables study of LSI aspects that may be difficult or unwieldy to address in an experimental setting, and enables detailed study of the fundamental origins of speckle contrast modulation in tissue-specific geometries. We applied the model to an in-depth exploration of the spectral dependence of speckle contrast signal in the skin, the effects of epidermal melanin content on LSI, and the depth-dependent origins of our signal. We found that LSI of transmitted light allows for a more homogeneous integration of the signal from the entire bulk of the tissue, whereas epi-illumination measurements of contrast are limited to a fraction of the light penetration depth. We quantified the spectral depth dependence of our contrast signal in the skin, and did not observe a statistically significant effect of epidermal melanin on speckle contrast. Finally, we corroborated these simulated results with experimental LSI measurements of flow beneath a thin absorbing layer. The results of this study suggest the use of LSI in the clinic to monitor perfusion in patients with different skin types, or inhomogeneous epidermal melanin distributions.
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Affiliation(s)
- Caitlin Regan
- Beckman Laser Institute, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California-Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
| | - Carole Hayakawa
- Beckman Laser Institute, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
| | - Bernard Choi
- Beckman Laser Institute, University of California-Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
- Department of Biomedical Engineering, University of California-Irvine, 3120 Natural Sciences II, Irvine, CA 92697, USA
- Department of Surgery, University of California-Irvine, 333 City Boulevard West, Suite 1600, Orange, CA 92868, USA
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, 2400 Engineering Hall, Irvine CA 92697, USA
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Choi B, Tan W, Jia W, White SM, Moy WJ, Yang BY, Zhu J, Chen Z, Kelly KM, Nelson JS. The Role of Laser Speckle Imaging in Port-Wine Stain Research: Recent Advances and Opportunities. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS : A PUBLICATION OF THE IEEE LASERS AND ELECTRO-OPTICS SOCIETY 2016; 2016:6800812. [PMID: 27013846 PMCID: PMC4800318 DOI: 10.1109/jstqe.2015.2493961] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Here, we review our current knowledge on the etiology and treatment of port-wine stain (PWS) birthmarks. Current treatment options have significant limitations in terms of efficacy. With the combination of 1) a suitable preclinical microvascular model, 2) laser speckle imaging (LSI) to evaluate blood-flow dynamics, and 3) a longitudinal experimental design, rapid preclinical assessment of new phototherapies can be translated from the lab to the clinic. The combination of photodynamic therapy (PDT) and pulsed-dye laser (PDL) irradiation achieves a synergistic effect that reduces the required radiant exposures of the individual phototherapies to achieve persistent vascular shutdown. PDL combined with anti-angiogenic agents is a promising strategy to achieve persistent vascular shutdown by preventing reformation and reperfusion of photocoagulated blood vessels. Integration of LSI into the clinical workflow may lead to surgical image guidance that maximizes acute photocoagulation, is expected to improve PWS therapeutic outcome. Continued integration of noninvasive optical imaging technologies and biochemical analysis collectively are expected to lead to more robust treatment strategies.
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Affiliation(s)
- Bernard Choi
- Departments of Biomedical Engineering and Surgery, the Beckman Laser Institute and Medical Clinic, and the Edwards Lifesciences Center for Advanced Cardiovascular Technology, all at University of California, Irvine 92612 USA
| | - Wenbin Tan
- Beckman Laser Institute and Medical Clinic, University of California, Irvine 92612 USA
| | - Wangcun Jia
- Beckman Laser Institute and Medical Clinic, University of California, Irvine 92612 USA
| | - Sean M. White
- Beckman Laser Institute and Medical Clinic, University of California, Irvine 92612 USA
| | - Wesley J. Moy
- Beckman Laser Institute and Medical Clinic, University of California, Irvine 92612 USA
| | - Bruce Y. Yang
- Beckman Laser Institute and Medical Clinic, University of California, Irvine 92612 USA
| | | | | | - Kristen M. Kelly
- Department of Dermatology and the Beckman Laser Institute and Medical Clinic, all at University of California, Irvine 92612 USA
| | - J. Stuart Nelson
- Departments of Biomedical Engineering and Surgery and the Beckman Laser Institute and Medical Clinic, all at University of California, Irvine 92612 USA
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Chen D, Ren J, Wang Y, Li B, Gu Y. Intraoperative monitoring of blood perfusion in port wine stains by laser Doppler imaging during vascular targeted photodynamic therapy: A preliminary study. Photodiagnosis Photodyn Ther 2016; 14:142-51. [PMID: 27068654 DOI: 10.1016/j.pdpdt.2016.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/11/2016] [Accepted: 04/05/2016] [Indexed: 01/01/2023]
Abstract
OBJECTIVE The objective of this study was to monitor blood perfusion dynamics of port wine stains (PWS) during vascular targeted photodynamic therapy (V-PDT) with laser Doppler imaging (LDI). METHODS The PWS lesions of 30 facial PWS patients received V-PDT, while the normal skins on the forearm of 5 healthy subjects were treated as light-only controls for comparison. Furthermore, two different PWS lesions in the same individual from each of 3 PWS patients successively received laser irradiation only and V-PDT, respectively. LDI was used to monitor intraoperative blood perfusion dynamics. RESULTS During V-PDT, the blood perfusion (278±96 PU) in PWS lesions for 31 of 33 PWS patients significantly increased after the initiation of V-PDT treatment, then reached a peak (638±105 PU) within 10min, followed by a slow decrease to a relatively lower level (515±100 PU). Furthermore, the time for reaching peak and the subsequent magnitude of decrease in blood perfusion varied with different patients. For light-only controls, an initial perfusion peak at 3min followed by a nadir and a secondary increase were found not only in normal skin, but also in PWS lesions. CONCLUSION The preliminary results showed that the LDI permits non-invasive monitoring blood perfusion changes of PWS lesions during V-PDT. There was a clear trend in blood perfusion responses during V-PDT and laser irradiation. The blood perfusion changes during treatment were due to V-PDT effects as well as local temperature increase induced by laser irradiation.
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Affiliation(s)
- Defu Chen
- School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China
| | - Jie Ren
- Department of Laser Medicine, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Ying Wang
- Department of Laser Medicine, Chinese People's Liberation Army General Hospital, Beijing 100853, China
| | - Buhong Li
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Provincial Key Laboratory for Photonics Technology, Fujian Normal University, Fujian 350007, China
| | - Ying Gu
- School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China; Department of Laser Medicine, Chinese People's Liberation Army General Hospital, Beijing 100853, China.
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Regan C, Choi B. Laser speckle imaging based on photothermally driven convection. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:26011. [PMID: 26927221 PMCID: PMC4962529 DOI: 10.1117/1.jbo.21.2.026011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 01/25/2016] [Indexed: 06/05/2023]
Abstract
Laser speckle imaging (LSI) is an interferometric technique that provides information about the relative speed of moving scatterers in a sample. Photothermal LSI overcomes limitations in depth resolution faced by conventional LSI by incorporating an excitation pulse to target absorption by hemoglobin within the vascular network. Here we present results from experiments designed to determine the mechanism by which photothermal LSI decreases speckle contrast. We measured the impact of mechanical properties on speckle contrast, as well as the spatiotemporal temperature dynamics and bulk convective motion occurring during photothermal LSI. Our collective data strongly support the hypothesis that photothermal LSI achieves a transient reduction in speckle contrast due to bulk motion associated with thermally driven convection. The ability of photothermal LSI to image structures below a scattering medium may have important preclinical and clinical applications.
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Affiliation(s)
- Caitlin Regan
- University of California–Irvine, Department of Biomedical Engineering, 3120 Natural Sciences II, Irvine, California 92697, United States
- Beckman Laser Institute and Medical Clinic, 1002 Health Sciences Road East, Irvine, California 92612, United States
| | - Bernard Choi
- University of California–Irvine, Department of Biomedical Engineering, 3120 Natural Sciences II, Irvine, California 92697, United States
- Beckman Laser Institute and Medical Clinic, 1002 Health Sciences Road East, Irvine, California 92612, United States
- University of California–Irvine, Department of Surgery, 333 City Boulevard West, Suite 1600, Orange, California 92868, United States
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, 2400 Engineering Hall, Irvine, California 92697, United States
- CHOC Children’s Hospital, 1201 West La Veta Avenue, Orange, California 92868, United States
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13
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Liu Q, Wang X, Jia Y, Long X, Yu N, Wang Y, Chen B. Increased blood flow in keloids and adjacent skin revealed by laser speckle contrast imaging. Lasers Surg Med 2016; 48:360-4. [PMID: 26749479 DOI: 10.1002/lsm.22470] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2015] [Indexed: 12/29/2022]
Affiliation(s)
- Qingliang Liu
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
| | - Xiaojun Wang
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
| | - Yihong Jia
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
| | - Xiao Long
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
| | - Nanze Yu
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
| | - Youbin Wang
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
| | - Bo Chen
- Department of Plastic and Reconstructive Surgery; Peking Union Medical College Hospital; Chinese Academy of Medical Sciences and Peking Union Medical College; Beijing 100730 People's Republic of China
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Yang B, Yang O, Guzman J, Nguyen P, Crouzet C, Osann KE, Kelly KM, Nelson JS, Choi B. Intraoperative, real-time monitoring of blood flow dynamics associated with laser surgery of port wine stain birthmarks. Lasers Surg Med 2015; 47:469-475. [PMID: 26040983 DOI: 10.1002/lsm.v47.6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND OBJECTIVE Port-wine stain (PWS) birthmarks affect ∼22 million people worldwide. After several treatment sessions, complete disappearance of the PWS occurs in only ∼10% of treated patients. There is a need to develop a new strategy to improve the efficacy of each treatment session and the overall treatment outcome. The study objective was to determine how intraoperative measurements of blood flow correlate with treatment response assessed several weeks post treatment. STUDY DESIGN/MATERIALS AND METHODS We employed Laser Speckle Imaging (LSI) to measure intraoperative blood-flow dynamics. We collected data from 24 subjects undergoing laser therapy for facial PWS birthmarks. Photographs were taken before treatment and at a follow-up visit, and analyzed by two expert observers. RESULTS Intraoperative LSI enables real-time monitoring of blood-flow dynamics in response to laser treatment and can inform clinicians on the need for focused re-treatment. The degree of PWS blanching achieved is positively correlated with the log-transformed acute blood-flow reduction (P = 0.022). CONCLUSION LSI is a simple, intraoperative monitoring tool during laser therapy of PWS birthmarks. LSI provides a single value for blood flow that correlates well with the degree of blanching achieved with laser therapy.
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Affiliation(s)
- Bruce Yang
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Biomedical Engineering, University of California, Irvine, California 92697
| | - Owen Yang
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Biomedical Engineering, University of California, Irvine, California 92697
| | - John Guzman
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Biomedical Engineering, University of California, Irvine, California 92697
| | - Paul Nguyen
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Biomedical Engineering, University of California, Irvine, California 92697
| | | | - Kathryn E Osann
- Division of Hematology/Oncology, School of Medicine, University of California, Irvine, California 92697
| | - Kristen M Kelly
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Dermatology, University of California, Irvine, California 92697
| | - J Stuart Nelson
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Biomedical Engineering, University of California, Irvine, California 92697
- Division of Hematology/Oncology, School of Medicine, University of California, Irvine, California 92697
- Department of Dermatology, University of California, Irvine, California 92697
- Department of Surgery, University of California, Irvine, California 92697
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612
- Department of Biomedical Engineering, University of California, Irvine, California 92697
- Department of Surgery, University of California, Irvine, California 92697
- Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, California 92697
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Yang B, Yang O, Guzman J, Nguyen P, Crouzet C, Osann KE, Kelly KM, Nelson JS, Choi B. Intraoperative, real-time monitoring of blood flow dynamics associated with laser surgery of port wine stain birthmarks. Lasers Surg Med 2015; 47:469-75. [PMID: 26040983 DOI: 10.1002/lsm.22369] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2015] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND OBJECTIVE Port-wine stain (PWS) birthmarks affect ∼22 million people worldwide. After several treatment sessions, complete disappearance of the PWS occurs in only ∼10% of treated patients. There is a need to develop a new strategy to improve the efficacy of each treatment session and the overall treatment outcome. The study objective was to determine how intraoperative measurements of blood flow correlate with treatment response assessed several weeks post treatment. STUDY DESIGN/MATERIALS AND METHODS We employed Laser Speckle Imaging (LSI) to measure intraoperative blood-flow dynamics. We collected data from 24 subjects undergoing laser therapy for facial PWS birthmarks. Photographs were taken before treatment and at a follow-up visit, and analyzed by two expert observers. RESULTS Intraoperative LSI enables real-time monitoring of blood-flow dynamics in response to laser treatment and can inform clinicians on the need for focused re-treatment. The degree of PWS blanching achieved is positively correlated with the log-transformed acute blood-flow reduction (P = 0.022). CONCLUSION LSI is a simple, intraoperative monitoring tool during laser therapy of PWS birthmarks. LSI provides a single value for blood flow that correlates well with the degree of blanching achieved with laser therapy.
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Affiliation(s)
- Bruce Yang
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Biomedical Engineering, University of California, Irvine, California 92697
| | - Owen Yang
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Biomedical Engineering, University of California, Irvine, California 92697
| | - John Guzman
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Biomedical Engineering, University of California, Irvine, California 92697
| | - Paul Nguyen
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Biomedical Engineering, University of California, Irvine, California 92697
| | | | - Kathryn E Osann
- Division of Hematology/Oncology, School of Medicine, University of California, Irvine, California 92697
| | - Kristen M Kelly
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Dermatology, University of California, Irvine, California 92697
| | - J Stuart Nelson
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Biomedical Engineering, University of California, Irvine, California 92697.,Division of Hematology/Oncology, School of Medicine, University of California, Irvine, California 92697.,Department of Dermatology, University of California, Irvine, California 92697.,Department of Surgery, University of California, Irvine, California 92697
| | - Bernard Choi
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612.,Department of Biomedical Engineering, University of California, Irvine, California 92697.,Department of Surgery, University of California, Irvine, California 92697.,Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, California 92697
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Allen J, Howell K. Microvascular imaging: techniques and opportunities for clinical physiological measurements. Physiol Meas 2014; 35:R91-R141. [DOI: 10.1088/0967-3334/35/7/r91] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Pasternak K, Nowacka O, Wróbel D, Pieszyński I, Bryszewska M, Kujawa J. Influence of MLS laser radiation on erythrocyte membrane fluidity and secondary structure of human serum albumin. Mol Cell Biochem 2013; 388:261-7. [PMID: 24357115 PMCID: PMC3912354 DOI: 10.1007/s11010-013-1917-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Accepted: 12/06/2013] [Indexed: 12/03/2022]
Abstract
The biostimulating activity of low level laser radiation of various wavelengths and energy doses is widely documented in the literature, but the mechanisms of the intracellular reactions involved are not precisely known. The aim of this paper is to evaluate the influence of low level laser radiation from an multiwave locked system (MLS) of two wavelengths (wavelength = 808 nm in continuous emission and 905 nm in pulsed emission) on the human erythrocyte membrane and on the secondary structure of human serum albumin (HSA). Human erythrocytes membranes and HSA were irradiated with laser light of low intensity with surface energy density ranging from 0.46 to 4.9 J cm−2 and surface energy power density 195 mW cm−2 (1,000 Hz) and 230 mW cm−2 (2,000 Hz). Structural and functional changes in the erythrocyte membrane were characterized by its fluidity, while changes in the protein were monitored by its secondary structure. Dose-dependent changes in erythrocyte membrane fluidity were induced by near-infrared laser radiation. Slight changes in the secondary structure of HSA were also noted. MLS laser radiation influences the structure and function of the human erythrocyte membrane resulting in a change in fluidity.
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Affiliation(s)
- Kamila Pasternak
- Clinic of Medical Rehabilitation, Medical University of Lodz, 75 Drewnowska Str, 91-002 Lodz, Poland
| | - Olga Nowacka
- Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, 141/143 Pomorska Str, 90-236 Lodz, Poland
| | - Dominika Wróbel
- Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, 141/143 Pomorska Str, 90-236 Lodz, Poland
| | - Ireneusz Pieszyński
- Clinic of Medical Rehabilitation, Medical University of Lodz, 75 Drewnowska Str, 91-002 Lodz, Poland
| | - Maria Bryszewska
- Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, 141/143 Pomorska Str, 90-236 Lodz, Poland
| | - Jolanta Kujawa
- Clinic of Medical Rehabilitation, Medical University of Lodz, 75 Drewnowska Str, 91-002 Lodz, Poland
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Frigerio A, Bhama PK, Tan OT. Quantitative three-dimensional assessment of port-wine stain clearance after laser treatments. Lasers Surg Med 2013; 45:633-8. [DOI: 10.1002/lsm.22176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2013] [Indexed: 01/16/2023]
Affiliation(s)
- Alice Frigerio
- Carolyn and Peter Lynch Center for Laser and Reconstructive Surgery; Harvard Medical School, Massachussets Eye and Ear Infirmary; Boston Massachusetts
| | - Prabhat K. Bhama
- Division of Facial Plastic and Reconstructive Surgery, Department of Otology and Laryngology; Harvard Medical School, Massachussets Eye and Ear Infirmary; Boston Massachusetts
| | - Oon T. Tan
- Carolyn and Peter Lynch Center for Laser and Reconstructive Surgery; Harvard Medical School, Massachussets Eye and Ear Infirmary; Boston Massachusetts
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Frigerio A, Bhama PK, Tan OT. Quantitative three-dimensional assessment of port-wine stain clearance after laser treatments. Lasers Surg Med 2013; 46:180-5. [PMID: 24155123 DOI: 10.1002/lsm.22193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2013] [Indexed: 01/15/2023]
Abstract
BACKGROUND AND OBJECTIVE Outcomes analysis of laser treatment for port-wine stains has been hampered by the lack of an objective measure of surface area and volume; moreover, treatment success is often gauged by clinician subjective assessment. Three-dimensional (3D) surface imaging has been applied in several medical disciplines to quantify surface changes, with promising results. We hypothesized that 3D surface imaging could be used to objectively measure changes in area and volume of port-wine stains following laser treatment. STUDY DESIGN/MATERIALS AND METHODS We performed a retrospective review of consecutive patients with port-wine stains treated over a 20-month time period. Area and volume of the lesions were measured using 3dMD photogrammetric software (3dMD, Atlanta, GA) before and after a series of sequential pulsed dye laser and/or alexandrite laser treatments. RESULTS Fifty-five patients with 59 port-wine stains were included in the study. The initial average measured area was 44.3 cm(2) ; final average measured area decreased to 36.9 cm(2) (P < 0.001). The average volume change was 1.20 cc for all PWS included in the study and 1.90 cc for lesions that received at least 5 laser treatments within the study period. CONCLUSION Three-dimensional photography demonstrated area and volume changes in patients with port-wine stains after laser treatments. Future studies to determine if statistically significant changes correlate with clinically appreciable changes are warranted.
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Affiliation(s)
- Alice Frigerio
- Carolyn and Peter Lynch Center for Laser and Reconstructive Surgery, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts
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Assessment of tissue perfusion changes in port wine stains after vascular targeted photodynamic therapy: a short-term follow-up study. Lasers Med Sci 2013; 29:781-8. [PMID: 23975603 DOI: 10.1007/s10103-013-1420-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 08/07/2013] [Indexed: 12/17/2022]
Abstract
The occlusion effect of vascular targeted photodynamic therapy (V-PDT) for malformed vessels in port wine stains (PWS) often last for some time after the treatment. A relatively longer period after V-PDT is needed to accurately assess the final response of PWS microcirculation to the treatment. In this study, we intended to use laser speckle imaging (LSI) to assess the tissue perfusion changes of PWS at follow-up after V-PDT and preliminarily analyze the relationship between perfusion change and color bleaching. Seventeen patients with 40 PWS lesions were scanned by LSI before and 3-6 months after they received V-PDT. The speckle flow indices of PWS lesions and normal skin before and at follow-up after V-PDT were recorded. We also performed analyses on the correlation between perfusion changes and color bleaching. Before V-PDT, the 40 PWS lesions showed higher perfusion than the normal skin (1,421 ± 463 and 1,115 ± 386 perfusion unit (PU), respectively, P < 0.01). The PWS lesions scanned at follow-up showed decreased perfusion level compared to the preoperative values (1,282 ± 460 and 1,421 ± 463 PU, respectively, P < 0.01). After V-PDT, the perfusion change rates coincide well with the color bleaching rates (correlation coefficient, 0.73). In conclusion, the LSI system is capable of imaging PWS perfusion precisely, and it has shown promising results in assessing the changes of tissue perfusion of V-PDT for PWS, with objective and quantitative data, real-time images, and a shorter detection time. It may also provide an effectiveness assessment method for the treatment of PWS.
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Senarathna J, Rege A, Li N, Thakor NV. Laser Speckle Contrast Imaging: theory, instrumentation and applications. IEEE Rev Biomed Eng 2013; 6:99-110. [PMID: 23372086 DOI: 10.1109/rbme.2013.2243140] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Laser Speckle Contrast Imaging (LSCI) is a wide field of view, non scanning optical technique for observing blood flow. Speckles are produced when coherent light scattered back from biological tissue is diffracted through the limiting aperture of focusing optics. Mobile scatterers cause the speckle pattern to blur; a model can be constructed by inversely relating the degree of blur, termed speckle contrast to the scatterer speed. In tissue, red blood cells are the main source of moving scatterers. Therefore, blood flow acts as a virtual contrast agent, outlining blood vessels. The spatial resolution (~10 μm) and temporal resolution (10 ms to 10 s) of LSCI can be tailored to the application. Restricted by the penetration depth of light, LSCI can only visualize superficial blood flow. Additionally, due to its non scanning nature, LSCI is unable to provide depth resolved images. The simple setup and non-dependence on exogenous contrast agents have made LSCI a popular tool for studying vascular structure and blood flow dynamics. We discuss the theory and practice of LSCI and critically analyze its merit in major areas of application such as retinal imaging, imaging of skin perfusion as well as imaging of neurophysiology.
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Affiliation(s)
- Janaka Senarathna
- Department of Biomedical Engineering, the Johns Hopkins University, Baltimore, MD 21205, USA.
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Sharif SA, Taydas E, Mazhar A, Rahimian R, Kelly KM, Choi B, Durkin AJ. Noninvasive clinical assessment of port-wine stain birthmarks using current and future optical imaging technology: a review. Br J Dermatol 2012; 167:1215-23. [PMID: 22804872 PMCID: PMC3508172 DOI: 10.1111/j.1365-2133.2012.11139.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Port-wine stain (PWS) birthmarks are one class of benign congenital vascular malformation. Laser therapy is the most successful treatment modality of PWS. Unfortunately, this approach has limited efficacy, with only 10% of patients experiencing complete blanching of the PWS. To address this problem, several research groups have developed technologies and methods designed to study treatment outcome and improve treatment efficacy. This article reviews seven optical imaging techniques currently in use or under development to assess treatment efficacy, focusing on: reflectance spectrophotometers/tristimulus colorimeters; laser Doppler flowmetry and laser Doppler imaging; cross-polarized diffuse reflectance colour imaging system; reflectance confocal microscopy; optical coherence tomography; spatial frequency domain imaging; and laser speckle imaging.
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Affiliation(s)
- S A Sharif
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612, USA.
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Abstract
Laser speckle imaging (LSI) is a noninvasive optical imaging technique able to provide wide-field two-dimensional maps of moving particles. Raw laser speckle images are typically taken with a scientific-grade monochrome camera. We demonstrate that a digital single-lens reflex (dSLR) camera with a Bayer filter is able to provide similar sensitivity despite taking information only from a specific pixel color. Here we demonstrate the effect of changing three primary dSLR exposure settings (i.e., aperture, exposure time/shutter speed, and gain/sensitivity (ISO)) on speckle contrast. In addition, we present data from an in vivo reactive hyperemia experiment that demonstrates the qualitative similarity in blood-flow dynamics visualized with a color dSLR and a scientific-grade monochrome camera.
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Affiliation(s)
- Owen Yang
- Department of Biomedical Engineering, University of California, Irvine, 3120 Natural Sciences II, Irvine, California 92697, USA.
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Mazhar A, Sharif SA, Cuccia JD, Nelson JS, Kelly KM, Durkin AJ. Spatial frequency domain imaging of port wine stain biochemical composition in response to laser therapy: a pilot study. Lasers Surg Med 2012; 44:611-21. [PMID: 22911574 DOI: 10.1002/lsm.22067] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2012] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND OBJECTIVE Objective methods to assess port wine stain (PWS) response to laser treatment have been the subject of various research efforts for several years. Herein, we present a pilot study using a newly developed, light emitting diode (LED) based spatial frequency domain imaging (SFDI) device to record quantitatively biochemical compositional changes in PWS after laser therapy. STUDY DESIGN/PATIENTS AND METHODS A SFDI system was used to image before, and after, five PWS treatment sessions [n = 4 subjects (one subject was imaged before and after two consecutive laser treatments)]. SFDI derived wide-field optical properties (absorption and scattering) and tissue chromophore concentrations including oxy-hemoglobin (ctO(2) Hb), deoxy-hemoglobin (ctHHb), total hemoglobin (ctTHb), and tissue oxygen saturation (stO(2) ) are presented for skin imaged prior to and immediately after laser treatment. The SFDI derived images were analyzed by comparing the above measurements in PWS to those of normal skin and tracking changes immediately after laser exposure. RESULTS Elevated oxy-hemoglobin (>20%) and tissue oxygen saturation (>5%) were measured in all PWS lesions and compared to values for normal skin prior to treatment. Laser treatment resulted in an increase in deoxy-hemoglobin (>100%), decrease in tissue oxygen saturation (>10%), and reduced scattering (>15%) in all PWS lesions. One subject was followed before and after two consecutive laser treatments and the overall improvement in PWS lesion blanching was quantitatively assessed by measuring a 45% decrease in dermal blood volume. CONCLUSION SFDI is a rapid non-contact wide-field optical technique that shows potential as an imaging device that can be used to quantify biochemical compositional changes in PWS after laser therapy. Future work will investigate the potential of SFDI to provide intra-operative guidance for laser therapy of PWS lesions on an individual patient basis.
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Affiliation(s)
- Amaan Mazhar
- Beckman Laser Institute, University of California, Irvine, California 92612, USA
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Qiu H, Zhou Y, Gu Y, Ang Q, Zhao S, Wang Y, Zeng J, Huang N. Monitoring Microcirculation Changes in Port Wine Stains During Vascular Targeted Photodynamic Therapy by Laser Speckle Imaging. Photochem Photobiol 2012; 88:978-84. [DOI: 10.1111/j.1751-1097.2012.01153.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chen JK, Ghasri P, Aguilar G, van Drooge AM, Wolkerstorfer A, Kelly KM, Heger M. An overview of clinical and experimental treatment modalities for port wine stains. J Am Acad Dermatol 2012; 67:289-304. [PMID: 22305042 DOI: 10.1016/j.jaad.2011.11.938] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 10/15/2011] [Accepted: 11/10/2011] [Indexed: 01/03/2023]
Abstract
Port wine stains (PWS) are the most common vascular malformation of the skin, occurring in 0.3% to 0.5% of the population. Noninvasive laser irradiation with flashlamp-pumped pulsed dye lasers (selective photothermolysis) currently comprises the gold standard treatment of PWS; however, the majority of PWS fail to clear completely after selective photothermolysis. In this review, the clinically used PWS treatment modalities (pulsed dye lasers, alexandrite lasers, neodymium:yttrium-aluminum-garnet lasers, and intense pulsed light) and techniques (combination approaches, multiple passes, and epidermal cooling) are discussed. Retrospective analysis of clinical studies published between 1990 and 2011 was performed to determine therapeutic efficacies for each clinically used modality/technique. In addition, factors that have resulted in the high degree of therapeutic recalcitrance are identified, and emerging experimental treatment strategies are addressed, including the use of photodynamic therapy, immunomodulators, angiogenesis inhibitors, hypobaric pressure, and site-specific pharmaco-laser therapy.
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Affiliation(s)
- Jennifer K Chen
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, California, USA
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Stoianovici C, Wilder-Smith P, Choi B. Assessment of pulpal vitality using laser speckle imaging. Lasers Surg Med 2012; 43:833-7. [PMID: 21956631 DOI: 10.1002/lsm.21090] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND OBJECTIVE The pulpal chamber of each tooth contains the vasculature necessary to maintain a viable tooth. A critical need exists to develop an objective, repeatable method to assess pulpal viability. We hypothesized that the existence of blood perfusion within the pulp can be determined with analysis of laser speckle imaging (LSI) patterns generated by transillumination of the tooth. STUDY DESIGN/MATERIALS AND METHODS We used nine extracted human cuspids and incisors. A Tygon tube was inserted into a channel created within each tooth and Intralipid pumped through the tube in a controlled manner with a syringe infusion pump. We evaluated the feasibility of LSI for flow assessment using both transillumination and epiillumination imaging configurations. With the transillumination geometry, we also assessed the effect of the angle of incidence of the probe laser light on the speckle flow index (SFI) values extracted from the collected speckle images. RESULTS Transillumination LSI, and not epiillumination LSI, enables differentiation between the absence and presence of perfusion in an in vitro tooth model. SFI values are insensitive to the relative angle of incidence of the laser light, over a wide range of angles. CONCLUSIONS Our preliminary in vitro data suggest that transillumination LSI is a promising method to identify the presence of blood flow in the pulpal chamber. Future in vivo evaluation is warranted.
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Affiliation(s)
- Charles Stoianovici
- Department of Surgery, Beckman Laser Institute and Medical Clinic, University of California, Irvine, California 92612, USA
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Jiang C, Zhang H, Wang J, Wang Y, He H, Liu R, Zhou F, Deng J, Li P, Luo Q. Dedicated hardware processor and corresponding system-on-chip design for real-time laser speckle imaging. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:116008. [PMID: 22112113 DOI: 10.1117/1.3651772] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Laser speckle imaging (LSI) is a noninvasive and full-field optical imaging technique which produces two-dimensional blood flow maps of tissues from the raw laser speckle images captured by a CCD camera without scanning. We present a hardware-friendly algorithm for the real-time processing of laser speckle imaging. The algorithm is developed and optimized specifically for LSI processing in the field programmable gate array (FPGA). Based on this algorithm, we designed a dedicated hardware processor for real-time LSI in FPGA. The pipeline processing scheme and parallel computing architecture are introduced into the design of this LSI hardware processor. When the LSI hardware processor is implemented in the FPGA running at the maximum frequency of 130 MHz, up to 85 raw images with the resolution of 640×480 pixels can be processed per second. Meanwhile, we also present a system on chip (SOC) solution for LSI processing by integrating the CCD controller, memory controller, LSI hardware processor, and LCD display controller into a single FPGA chip. This SOC solution also can be used to produce an application specific integrated circuit for LSI processing.
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Affiliation(s)
- Chao Jiang
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Wuhan, China
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An overview of three promising mechanical, optical, and biochemical engineering approaches to improve selective photothermolysis of refractory port wine stains. Ann Biomed Eng 2011; 40:486-506. [PMID: 22016324 PMCID: PMC3281205 DOI: 10.1007/s10439-011-0436-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 10/06/2011] [Indexed: 11/25/2022]
Abstract
During the last three decades, several laser systems, ancillary technologies, and treatment modalities have been developed for the treatment of port wine stains (PWSs). However, approximately half of the PWS patient population responds suboptimally to laser treatment. Consequently, novel treatment modalities and therapeutic techniques/strategies are required to improve PWS treatment efficacy. This overview therefore focuses on three distinct experimental approaches for the optimization of PWS laser treatment. The approaches are addressed from the perspective of mechanical engineering (the use of local hypobaric pressure to induce vasodilation in the laser-irradiated dermal microcirculation), optical engineering (laser-speckle imaging of post-treatment flow in laser-treated PWS skin), and biochemical engineering (light- and heat-activatable liposomal drug delivery systems to enhance the extent of post-irradiation vascular occlusion).
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Kaiser M, Yafi A, Cinat M, Choi B, Durkin AJ. Noninvasive assessment of burn wound severity using optical technology: a review of current and future modalities. Burns 2011; 9:207-12. [PMID: 21185123 DOI: 10.1117/1.1629680] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 08/30/2010] [Accepted: 11/10/2010] [Indexed: 05/18/2023]
Abstract
Clinical examination alone is not always sufficient to determine which burn wounds will heal spontaneously and which will require surgical intervention for optimal outcome. We present a review of optical modalities currently in clinical use and under development to assist burn surgeons in assessing burn wound severity, including conventional histology/light microscopy, laser Doppler imaging, indocyanine green videoangiography, near-infrared spectroscopy and spectral imaging, in vivo capillary microscopy, orthogonal polarization spectral imaging, reflectance-mode confocal microscopy, laser speckle imaging, spatial frequency domain imaging, photoacoustic microscopy, and polarization-sensitive optical coherence tomography.
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Affiliation(s)
- Meghann Kaiser
- Department of Surgery, Division of Trauma, Burns, Critical Care and Acute Care Surgery, University of California, Irvine, Orange, CA 92806, USA.
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Yang O, Cuccia D, Choi B. Real-time blood flow visualization using the graphics processing unit. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:016009. [PMID: 21280915 PMCID: PMC3055590 DOI: 10.1117/1.3528610] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Laser speckle imaging (LSI) is a technique in which coherent light incident on a surface produces a reflected speckle pattern that is related to the underlying movement of optical scatterers, such as red blood cells, indicating blood flow. Image-processing algorithms can be applied to produce speckle flow index (SFI) maps of relative blood flow. We present a novel algorithm that employs the NVIDIA Compute Unified Device Architecture (CUDA) platform to perform laser speckle image processing on the graphics processing unit. Software written in C was integrated with CUDA and integrated into a LabVIEW Virtual Instrument (VI) that is interfaced with a monochrome CCD camera able to acquire high-resolution raw speckle images at nearly 10 fps. With the CUDA code integrated into the LabVIEW VI, the processing and display of SFI images were performed also at ∼10 fps. We present three video examples depicting real-time flow imaging during a reactive hyperemia maneuver, with fluid flow through an in vitro phantom, and a demonstration of real-time LSI during laser surgery of a port wine stain birthmark.
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Affiliation(s)
- Owen Yang
- University of California, Irvine, Beckman Laser Institute and Medical Clinic, Department of Biomedical Engineering, 1002 Health Sciences Road, Irvine, California 92612, USA.
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Kaiser M, Yafi A, Cinat M, Choi B, Durkin AJ. Noninvasive assessment of burn wound severity using optical technology: a review of current and future modalities. Burns 2010; 37:377-86. [PMID: 21185123 DOI: 10.1016/j.burns.2010.11.012] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 08/30/2010] [Accepted: 11/10/2010] [Indexed: 11/19/2022]
Abstract
Clinical examination alone is not always sufficient to determine which burn wounds will heal spontaneously and which will require surgical intervention for optimal outcome. We present a review of optical modalities currently in clinical use and under development to assist burn surgeons in assessing burn wound severity, including conventional histology/light microscopy, laser Doppler imaging, indocyanine green videoangiography, near-infrared spectroscopy and spectral imaging, in vivo capillary microscopy, orthogonal polarization spectral imaging, reflectance-mode confocal microscopy, laser speckle imaging, spatial frequency domain imaging, photoacoustic microscopy, and polarization-sensitive optical coherence tomography.
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Affiliation(s)
- Meghann Kaiser
- Department of Surgery, Division of Trauma, Burns, Critical Care and Acute Care Surgery, University of California, Irvine, Orange, CA 92806, USA.
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Tang X, Feng N, Sun X, Li P, Luo Q. Portable laser speckle perfusion imaging system based on digital signal processor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:125110. [PMID: 21198054 DOI: 10.1063/1.3505118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The ability to monitor blood flow in vivo is of major importance in clinical diagnosis and in basic researches of life science. As a noninvasive full-field technique without the need of scanning, laser speckle contrast imaging (LSCI) is widely used to study blood flow with high spatial and temporal resolution. Current LSCI systems are based on personal computers for image processing with large size, which potentially limit the widespread clinical utility. The need for portable laser speckle contrast imaging system that does not compromise processing efficiency is crucial in clinical diagnosis. However, the processing of laser speckle contrast images is time-consuming due to the heavy calculation for enormous high-resolution image data. To address this problem, a portable laser speckle perfusion imaging system based on digital signal processor (DSP) and the algorithm which is suitable for DSP is described. With highly integrated DSP and the algorithm, we have markedly reduced the size and weight of the system as well as its energy consumption while preserving the high processing speed. In vivo experiments demonstrate that our portable laser speckle perfusion imaging system can obtain blood flow images at 25 frames per second with the resolution of 640 × 480 pixels. The portable and lightweight features make it capable of being adapted to a wide variety of application areas such as research laboratory, operating room, ambulance, and even disaster site.
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Affiliation(s)
- Xuejun Tang
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China
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Ramírez-San-Juan JC, Huang YC, Salazar-Hermenegildo N, Ramos-García R, Muñoz-Lopez J, Choi B. Integration of image exposure time into a modified laser speckle imaging method. Phys Med Biol 2010; 55:6857-66. [PMID: 21048287 DOI: 10.1088/0031-9155/55/22/016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Speckle-based methods have been developed to characterize tissue blood flow and perfusion. One such method, called modified laser speckle imaging (mLSI), enables computation of blood flow maps with relatively high spatial resolution. Although it is known that the sensitivity and noise in LSI measurements depend on image exposure time, a fundamental disadvantage of mLSI is that it does not take into account this parameter. In this work, we integrate the exposure time into the mLSI method and provide experimental support of our approach with measurements from an in vitro flow phantom.
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Parthasarathy AB, Weber EL, Richards LM, Fox DJ, Dunn AK. Laser speckle contrast imaging of cerebral blood flow in humans during neurosurgery: a pilot clinical study. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:066030. [PMID: 21198204 PMCID: PMC9113397 DOI: 10.1117/1.3526368] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 10/26/2010] [Accepted: 11/05/2010] [Indexed: 05/18/2023]
Abstract
Monitoring cerebral blood flow (CBF) during neurosurgery can provide important physiological information for a variety of surgical procedures. CBF measurements are important for assessing whether blood flow has returned to presurgical baseline levels and for assessing postsurgical tissue viability. Existing techniques for intraoperative monitoring of CBF based on magnetic resonance imaging are expensive and often impractical, while techniques such as indocyanine green angiography cannot produce quantitative measures of blood flow. Laser speckle contrast imaging (LSCI) is an optical technique that has been widely used to quantitatively image relative CBF in animal models in vivo. In a pilot clinical study, we adapted an existing neurosurgical operating microscope to obtain LSCI images in humans in real time during neurosurgery under baseline conditions and after bipolar cautery. Simultaneously recorded ECG waveforms from the patient were used to develop a filter that helped reduce measurement variabilities due to motion artifacts. Results from this study demonstrate the feasibility of using LSCI to obtain blood flow images during neurosurgeries and its capability to produce full field CBF image maps with excellent spatial resolution in real-time with minimal disruption to the surgical procedure.
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Affiliation(s)
- Ashwin B. Parthasarathy
- The University of Texas at
Austin, Department of Biomedical Engineering, Austin, Texas
78712
| | - Erica L. Weber
- The University of Texas at
Austin, Department of Biomedical Engineering, Austin, Texas
78712
| | - Lisa M. Richards
- The University of Texas at
Austin, Department of Biomedical Engineering, Austin, Texas
78712
| | - Douglas J. Fox
- St. David's Hospital, NeuroTexas
Institute, Austin, Texas 78705
| | - Andrew K. Dunn
- The University of Texas at
Austin, Department of Biomedical Engineering, Austin, Texas
78712
- Address all correspondence to: Andrew K. Dunn, The University of
Texas at Austin, Department of Biomedical Engineering, Austin, Texas 78712; Tel:
512-232-2808; E-mail:
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Naramore WJ, Chou NY. Next wave of optical imaging-clinical applications of laser speckle. Biomed Instrum Technol 2010; 44:54-7. [PMID: 20374126 DOI: 10.2345/0899-8205-44.1.54] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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