1
|
Hu XX, Xing XM, Zhang ZM, Zhang C, Chen L, Huang JZ, Wang X, Ma X, Geng X. Wearable laser Doppler flowmetry for non-invasive assessment of diabetic foot microcirculation: methodological considerations and clinical implications. J Biomed Opt 2024; 29:065001. [PMID: 38737791 PMCID: PMC11088439 DOI: 10.1117/1.jbo.29.6.065001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/15/2024] [Accepted: 04/18/2024] [Indexed: 05/14/2024]
Abstract
Significance Type 2 diabetes mellitus (T2DM) is a global health concern with significant implications for vascular health. The current evaluation methods cannot achieve effective, portable, and quantitative evaluation of foot microcirculation. Aim We aim to use a wearable device laser Doppler flowmetry (LDF) to evaluate the foot microcirculation of T2DM patients at rest. Approach Eleven T2DM patients and twelve healthy subjects participated in this study. The wearable LDF was used to measure the blood flows (BFs) for regions of the first metatarsal head (M1), fifth metatarsal head (M5), heel, and dorsal foot. Typical wavelet analysis was used to decompose the five individual control mechanisms: endothelial, neurogenic, myogenic, respiratory, and heart components. The mean BF and sample entropy (SE) were calculated, and the differences between diabetic patients and healthy adults and among the four regions were compared. Results Diabetic patients showed significantly reduced mean BF in the neurogenic (p = 0.044 ) and heart (p = 0.001 ) components at the M1 and M5 regions (p = 0.025 ) compared with healthy adults. Diabetic patients had significantly lower SE in the neurogenic (p = 0.049 ) and myogenic (p = 0.032 ) components at the M1 region, as well as in the endothelial (p < 0.001 ) component at the M5 region and in the myogenic component at the dorsal foot (p = 0.007 ), compared with healthy adults. The SE in the myogenic component at the dorsal foot was lower than at the M5 region (p = 0.050 ) and heel area (p = 0.041 ). Similarly, the SE in the heart component at the dorsal foot was lower than at the M5 region (p = 0.017 ) and heel area (p = 0.028 ) in diabetic patients. Conclusions This study indicated the potential of using the novel wearable LDF device for tracking vascular complications and implementing targeted interventions in T2DM patients.
Collapse
Affiliation(s)
- Xing-Xi Hu
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
- The Affiliated Hospital of Yunnan University (The Second People’s Hospital of Yunnan Province, The Eye Hospital of Yunnan Province), Department of Orthopedics and Trauma, Kunming, China
| | - Xiao-Man Xing
- University of Science and Technology of China, School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, Suzhou, China
- Chinese Academy of Sciences, Suzhou Institute of Biomedical Engineering and Technology, Suzhou, China
| | - Zhen-Ming Zhang
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
| | - Chao Zhang
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
| | - Li Chen
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
| | - Jia-Zhang Huang
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
| | - Xu Wang
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
| | - Xin Ma
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
- National Center for Orthopaedics, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiang Geng
- Huashan Hospital, Fudan University, Department of Orthopedic Surgery, Shanghai, China
| |
Collapse
|
2
|
Ajan A, Roberg K, Fredriksson I, Abtahi J. Reproducibility of Laser Doppler Flowmetry in gingival microcirculation. A study on six different protocols. Microvasc Res 2024; 153:104666. [PMID: 38301938 DOI: 10.1016/j.mvr.2024.104666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 01/13/2024] [Accepted: 01/25/2024] [Indexed: 02/03/2024]
Abstract
OBJECTIVES Laser Doppler Flowmetry (LDF) is a non-invasive technique for the assessment of tissue blood flow, but increased reproducibility would facilitate longitudinal studies. The aim of the study was to assess the interday reproducibility of Laser Doppler Flowmetry (LDF) at rest, at elevated local temperatures, and with the use of the vasodilator Methyl Nicotinate (MN) in six interconnected protocols for the measurement of the blood supply to the microvascular bed of the gingiva. METHODS Ten healthy volunteers were included. Interweek LDF measurements with custom-made acrylic splints were performed. Six protocols were applied in separate regions of interest (ROI): 1; basal LDF, 2; LDF with thermoprobe 42 °C, 3; LDF with thermoprobe 45 °C, 4; LDF with thermoprobe 42 °C and MN, 5; LDF with thermoprobe 45 °C and MN and 6; LDF with MN. RESULTS Intra-individual reproducibility was assessed by the within-subject coefficient of variation (wCV) and the intraclass correlation coefficient (ICC). Basal LDF measurements demonstrated high reproducibility with wCV 11.1 in 2 min and 10.3 in 5 min. ICC was 0.9 and 0.92. wCV after heat and MN was 4.9-10.3 and ICC 0.82-0.93. The topically applied MN yielded increased blood flow. CONCLUSION This is the first study evaluating the reproducibility of basal LDF compared to single or multiple vasodilatory stimuli in gingiva. Multiple collector fibers probe and stabilizing acrylic splints are recommended. Vasodilatory stimulation showed a tendency toward higher reproducibility. Furthermore, MN yields vasodilation in gingiva.
Collapse
Affiliation(s)
- Aida Ajan
- Department of Oral and Maxillofacial Surgery, Linköping University Hospital, Linköping, Sweden; Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden.
| | - Karin Roberg
- Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden; Department of Otorhinolaryngology in Linköping, Region Östergötland, Linköping, Sweden.
| | - Ingemar Fredriksson
- Department of Biomedical Engineering (IMT), Linköping University, Linköping, Sweden.
| | - Jahan Abtahi
- Department of Oral and Maxillofacial Surgery, Linköping University Hospital, Linköping, Sweden; Department of Biomedical and Clinical Sciences (BKV), Linköping University, Linköping, Sweden.
| |
Collapse
|
3
|
Ramprasad A, Ezekwe A, Lee BR, Balasubramanian S, Jones BL. The impact of skin color and tone on histamine iontophoresis and Doppler flowmetry measurements as a pharmacodynamic biomarker. Clin Transl Sci 2024; 17:e13777. [PMID: 38511581 PMCID: PMC10955605 DOI: 10.1111/cts.13777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/29/2024] [Accepted: 03/07/2024] [Indexed: 03/22/2024] Open
Abstract
The phenotypical manifestations of asthma among children are diverse and exhibit varying responses to therapeutic interventions. There is a need to develop objective biomarkers to improve the characterization of allergic and inflammatory responses relevant to asthma to predict therapeutic treatment responses. We have previously investigated histamine iontophoresis with laser Doppler flowmetry (HILD) as a potential surrogate biomarker that characterizes histamine response and may be utilized to guide the treatment of allergic and inflammatory disease. We have identified intra-individual variability of HILD response type among children and adults with asthma and that HILD response type varied in association with racial classification. As laser Doppler flowimetry may be impacted by skin color, we aimed to further validate the HILD method by determining if skin color or tone is associated with observed HILD response type differences. We conducted an observational study utilizing quantification of skin color and tone obtained from photographs of the skin among participants during HILD assessments via the RGB color model. We compared RGB values across racial, ethnic, and HILD response type via the Kruskal-Wallis test and calculated Kendall rank correlation coefficient to evaluate the relationship between RGB composite scores and HILD pharmacodynamic measures. We observed that RGB scores differed among racial groups and histamine response phenotypes (p < 0.05). However, there was a lack of correlation between the RGB composite score and HILD pharmacodynamic measures (r values 0.1, p > 0.05). These findings suggest that skin color may not impact HILD response variations, necessitating further research to understand previously observed differences across identified racial groups.
Collapse
Affiliation(s)
- Aarya Ramprasad
- University of Missouri‐Kansas City School of MedicineKansas CityMissouriUSA
| | - Adara Ezekwe
- Division of Pediatric Clinical Pharmacology and Therapeutic Innovation and Section of Allergy/Asthma/ImmunologyChildren's Mercy HospitalKansas CityMissouriUSA
| | - Brian R. Lee
- University of Missouri‐Kansas City School of MedicineKansas CityMissouriUSA
- Division of Health Services and Outcomes ResearchChildren's Mercy HospitalKansas CityMissouriUSA
| | | | - Bridgette L. Jones
- University of Missouri‐Kansas City School of MedicineKansas CityMissouriUSA
- Division of Pediatric Clinical Pharmacology and Therapeutic Innovation and Section of Allergy/Asthma/ImmunologyChildren's Mercy HospitalKansas CityMissouriUSA
- Department of PediatricsUniversity of Missouri‐Kansas City School of MedicineKansas CityMissouriUSA
| |
Collapse
|
4
|
Wang Q, Wang Q, Ning Z, Chan KF, Jiang J, Wang Y, Su L, Jiang S, Wang B, Ip BYM, Ko H, Leung TWH, Chiu PWY, Yu SCH, Zhang L. Tracking and navigation of a microswarm under laser speckle contrast imaging for targeted delivery. Sci Robot 2024; 9:eadh1978. [PMID: 38381838 DOI: 10.1126/scirobotics.adh1978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 01/26/2024] [Indexed: 02/23/2024]
Abstract
Micro/nanorobotic swarms consisting of numerous tiny building blocks show great potential in biomedical applications because of their collective active delivery ability, enhanced imaging contrast, and environment-adaptive capability. However, in vivo real-time imaging and tracking of micro/nanorobotic swarms remain a challenge, considering the limited imaging size and spatial-temporal resolution of current imaging modalities. Here, we propose a strategy that enables real-time tracking and navigation of a microswarm in stagnant and flowing blood environments by using laser speckle contrast imaging (LSCI), featuring full-field imaging, high temporal-spatial resolution, and noninvasiveness. The change in dynamic convection induced by the microswarm can be quantitatively investigated by analyzing the perfusion unit (PU) distribution, offering an alternative approach to investigate the swarm behavior and its interaction with various blood environments. Both the microswarm and surrounding environment were monitored and imaged by LSCI in real time, and the images were further analyzed for simultaneous swarm tracking and navigation in the complex vascular system. Moreover, our strategy realized real-time tracking and delivery of a microswarm in vivo, showing promising potential for LSCI-guided active delivery of microswarm in the vascular system.
Collapse
Affiliation(s)
- Qinglong Wang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Qianqian Wang
- Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing, China
| | - Zhipeng Ning
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Kai Fung Chan
- Chow Yuk Ho Technology Centre for Innovative Medicine, CUHK, Shatin, N.T., Hong Kong, China
- Multi-Scale Medical Robotics Center, Hong Kong Science Park, Shatin, N.T., Hong Kong SAR, China
| | - Jialin Jiang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Yuqiong Wang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Lin Su
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Shuai Jiang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
| | - Ben Wang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, China
| | - Bonaventure Yiu Ming Ip
- Division of Neurology, Department of Medicine and Therapeutics, CUHK, Shatin, N.T., Hong Kong, China
| | - Ho Ko
- Division of Neurology, Department of Medicine and Therapeutics, CUHK, Shatin, N.T., Hong Kong, China
| | - Thomas Wai Hong Leung
- Division of Neurology, Department of Medicine and Therapeutics, CUHK, Shatin, N.T., Hong Kong, China
| | - Philip Wai Yan Chiu
- Chow Yuk Ho Technology Centre for Innovative Medicine, CUHK, Shatin, N.T., Hong Kong, China
- Multi-Scale Medical Robotics Center, Hong Kong Science Park, Shatin, N.T., Hong Kong SAR, China
- Department of Surgery, CUHK, Shatin, N.T., Hong Kong, China
| | - Simon Chun Ho Yu
- Department of Imaging and Interventional Radiology, CUHK, Shatin, N.T., Hong Kong, China
| | - Li Zhang
- Department of Mechanical and Automation Engineering, Chinese University of Hong Kong (CUHK), Shatin, N.T., Hong Kong, China
- Chow Yuk Ho Technology Centre for Innovative Medicine, CUHK, Shatin, N.T., Hong Kong, China
- Multi-Scale Medical Robotics Center, Hong Kong Science Park, Shatin, N.T., Hong Kong SAR, China
- Department of Surgery, CUHK, Shatin, N.T., Hong Kong, China
- CUHK T Stone Robotics Institute, CUHK, Shatin, N.T., Hong Kong, China
| |
Collapse
|
5
|
Watanabe K, Shiba T, Takahara A, Homma H, Komatsu T, Tanino Y, Nagasawa Y, Aimoto M, Hori Y. Evaluating the relationship between ocular blood flow and systemic organ blood flow in hemorrhagic shock using a rabbit model. Sci Rep 2024; 14:3749. [PMID: 38355984 PMCID: PMC10866860 DOI: 10.1038/s41598-024-54467-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 02/13/2024] [Indexed: 02/16/2024] Open
Abstract
This study aimed to investigate the feasibility of utilizing noninvasive ocular blood flow measurements as potential indicators of systemic circulation in rabbits experiencing hemorrhagic shock. Using Laser speckle flowgraphy, ocular blood flow indices, relative flow volume (RFV), and mean blur rate in the choroidal area (MBR-CH) were assessed in New Zealand White rabbits (n = 10) subjected to controlled blood removal and return. Hemodynamic parameters and biochemical markers were monitored alongside ocular circulation during blood removal and return phases. Additionally, correlations between ocular parameters and systemic indices were examined. The results indicated that RFV and MBR-CH exhibited significant correlations with renal and intestinal blood flows, with stronger correlations observed during blood removal. Additionally, ocular blood flow changes closely mirrored systemic dynamics, suggesting their potential as real-time indicators of shock progression and recovery. These findings indicate that ocular blood flow measurements may serve as real-time indicators of the systemic circulation status during hemorrhagic shock, offering potential insights into shock management and guiding tailored interventions. Thus, noninvasive ocular blood flow evaluation holds promise as an innovative tool for assessing systemic circulation dynamics during hemorrhagic shock.
Collapse
Affiliation(s)
- Kento Watanabe
- Department of Ophthalmology, Toho University, 6-11-1, Omorinishi, Oota-ku, Tokyo, 143-8541, Japan.
| | - Tomoaki Shiba
- Department of Ophthalmology, International University of Health and Welfare Narita Hospital, Chiba, Japan
| | - Akira Takahara
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Hiroshi Homma
- Department of Emergency and Critical Care Medicine, Tokyo Medical University, Tokyo, Japan
| | - Tetsuya Komatsu
- Department of Ophthalmology, Toho University, 6-11-1, Omorinishi, Oota-ku, Tokyo, 143-8541, Japan
| | - Yusuke Tanino
- Department of Emergency and Critical Care Medicine, Tokyo Medical University, Tokyo, Japan
| | - Yoshinobu Nagasawa
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Megumi Aimoto
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Chiba, Japan
| | - Yuichi Hori
- Department of Ophthalmology, Toho University, 6-11-1, Omorinishi, Oota-ku, Tokyo, 143-8541, Japan
| |
Collapse
|
6
|
Kou S, Leng X, Luo H, Nie H, Zhu Q. Acoustic resolution photoacoustic Doppler flowmetry for assessment of patient rectal cancer blood perfusion. J Biomed Opt 2024; 29:S11517. [PMID: 38223679 PMCID: PMC10787588 DOI: 10.1117/1.jbo.29.s1.s11517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 12/18/2023] [Accepted: 12/21/2023] [Indexed: 01/16/2024]
Abstract
Significance Photoacoustic Doppler flowmetry offers quantitative blood perfusion information in addition to photoacoustic vascular contrast for rectal cancer assessment. Aim We aim to develop and validate a correlational Doppler flowmetry utilizing an acoustic resolution photoacoustic microscopy (AR-PAM) system for blood perfusion analysis. Approach To extract blood perfusion information, we implemented AR-PAM Doppler flowmetry consisting of signal filtering and conditioning, A-line correlation, and angle compensation. We developed flow phantoms and contrast agent to systemically investigate the flowmetry's efficacy in a series of phantom studies. The developed correlational Doppler flowmetry was applied to images collected during in vivo AR-PAM for post-treatment rectal cancer evaluation. Results The linearity and accuracy of the Doppler flow measurement system were validated in phantom studies. Imaging rectal cancer patients treated with chemoradiation demonstrated the feasibility of using correlational Doppler flowmetry to assess treatment response and distinguish residual cancer from cancer-free tumor bed tissue and normal rectal tissue. Conclusions A new correlational Doppler flowmetry was developed and validated through systematic phantom evaluations. The results of its application to in vivo patients suggest it could be a useful addition to photoacoustic endoscopy for post-treatment rectal cancer assessment.
Collapse
Affiliation(s)
- Sitai Kou
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
| | - Xiandong Leng
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
| | - Hongbo Luo
- Washington University in St. Louis, Department of Electrical and System Engineering, St. Louis, Missouri, United States
| | - Haolin Nie
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
| | - Quing Zhu
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
- Washington University in St. Louis, Department of Electrical and System Engineering, St. Louis, Missouri, United States
- Washington University School of Medicine, Department of Radiology, St. Louis, Missouri, United States
| |
Collapse
|
7
|
Uğur-Aydın Z, Kılınç H, Akbaş Y, Usta SN. Evaluation of the effect of different desensitizers on pulpal blood flow after full crown preparation using laser Doppler flowmetry: a randomized clinical trial. Odontology 2024; 112:272-278. [PMID: 37354297 DOI: 10.1007/s10266-023-00828-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 06/12/2023] [Indexed: 06/26/2023]
Abstract
This study aims to evaluate the effect of Teethmate, Bifluoride 12, and Copal Varnish on the treatment of dentin hypersensitivity and the pulpal blood flow using laser Doppler flowmetry (LDF) after full crown preparations. Eighteen patients with 42 teeth with dentine hypersensitivity after full crown preparations were randomly treated with Teethmate, Bifluoride 12, and Copal Varnish. Dentine hypersensitivity was measured using a visual analog scale (VAS) and Schiff air index (SAI). LDF was used to assess the pulpal blood flow and results were recorded in perfusion units (PU). All measurements were performed at baseline, 5 min, 7 days, and 1 month after the application of desensitizers. Data were statistically analyzed by Wilcoxon and two-way ANOVA tests (p < 0.05). There was no significant difference between the tested desensitizers regarding VAS and PU values. VAS values decreased significantly at 7 days and 1 month after the application of desensitizers compared to baseline in all groups. The decrease in PU values significantly differed only in the Copal Varnish group at 5 min and 7 days after the application of the desensitizer (p < 0.05). A statistically significant difference was found between different times regarding SAI scores in all groups (p < 0.05). Teethmate, Bifluoride 12, and Copal Varnish showed similar effectiveness on dentine hypersensitivity and pulpal blood flow. Long-term clinical trials with larger sample sizes and histological studies are needed to evaluate their impacts on pulpal status.
Collapse
Affiliation(s)
- Zeliha Uğur-Aydın
- Department of Endodontics, Gulhane Faculty of Dentistry, University of Health Sciences, Ankara, Turkey
| | - Hamiyet Kılınç
- Department of Prosthodontics, Faculty of Dentistry, University of Bolu Abant Izzet Baysal, Bolu, Turkey
| | - Yasemin Akbaş
- Department of Prosthodontics, Faculty of Dentistry, University of Bolu Abant Izzet Baysal, Bolu, Turkey
| | - Sıla Nur Usta
- Department of Endodontics, Gulhane Faculty of Dentistry, University of Health Sciences, Ankara, Turkey.
| |
Collapse
|
8
|
Safonova TN, Kintyukhina NP, Timoshenkova EI. [Laser Doppler flowmetry in the diagnosis of chronic mixed blepharitis]. Vestn Oftalmol 2024; 140:68-72. [PMID: 38739133 DOI: 10.17116/oftalma202414002268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
Chronic mixed blepharitis accounts for 51.7% of all ophthalmic diseases. The use of laser Doppler flowmetry (LDF) in the diagnosis of this disease can help establish the initial manifestations of the inflammatory process in the eyelids, which is important for the prevention of possible complications - dry eye disease. PURPOSE This study was conducted to determine the sensitivity and specificity of the LDF method in the diagnosis of chronic mixed blepharitis based on the study of microcirculatory changes in the eyelid skin. MATERIAL AND METHODS The study included 23 patients with chronic mixed blepharitis (mean age 67±5.8 years) and 18 healthy volunteers (mean age 63±1.1 years). LDF was performed using the LAZMA MC-1 device. ROC analysis was used to determine sensitivity and specificity. RESULTS A typical disturbance of the eyelid skin microcirculation was revealed in chronic mixed blepharitis - ischemia - with inhibition of the intensity of the functioning of blood flow regulatory systems and moderate activation of the lymph flow. The sensitivity and specificity of the coefficient of variation (reflecting the vasomotor activity of microvessels) of blood flow was 71.43 and 71.43%, lymph flow - 65.71 and 80.00%; myogenic rhythms of blood flow - 83.33 and 85.71%, lymph flow - 66.67 and 71.43%; neurogenic rhythms of blood flow - 75.00 and 78.57%, lymph flow - 91.67 and 78.57%, respectively. CONCLUSION Laser Doppler flowmetry of the eyelid skin in combination with clinical, functional and instrumental research methods helped reveal with high sensitivity and specificity the eyelid damage in chronic mixed blepharitis. This method allows assessment of the condition of the eyelids in individuals without diseases of the anterior segment of the eye.
Collapse
Affiliation(s)
- T N Safonova
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
| | | | | |
Collapse
|
9
|
Zhao L, Liu S, Liu Y, Tang H. Vasomotion heterogeneity and spectral characteristics in diabetic and hypertensive patients. Microvasc Res 2024; 151:104620. [PMID: 37923118 DOI: 10.1016/j.mvr.2023.104620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/13/2023] [Accepted: 10/28/2023] [Indexed: 11/07/2023]
Abstract
Vasomotion refers to the spontaneous oscillation of blood vessels within a frequency range of 0.01 to 1.6 Hz. Various disease states, including hypertension and diabetes, have been associated with alterations in vasomotion at the finger, indicating potential impairment of skin microcirculation. Due to the non-linear nature of human vasculature, the modification of vasomotion may vary across different locations for different diseases. In this study, Laser Doppler Flowmetry was used to measure blood flow motion at acupoints LU8, LU5, SP6, and PC3 among 49 participants with or without diabetes and/or hypertension. Fast Fourier Transformation was used to analyze noise type while Hilbert-Huang Transformation and wavelet analysis were applied to assess Signal Noise Ratio (SNR) results. Statistical analysis revealed that different acupoints exhibit distinct spectral characteristics of vasomotion not only among healthy individuals but also among patients with diabetes and/or hypertension. The results showed strong heterogeneity of vasomotion among blood vessels, indicating that the vasomotion measured at a certain point may not reflect the real status of microcirculation.
Collapse
Affiliation(s)
- Liangjing Zhao
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Shuhong Liu
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Yang Liu
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Hui Tang
- Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
| |
Collapse
|
10
|
Li H, Bu Q, Shi X, Xu X, Li J. Non-invasive medical imaging technology for the diagnosis of burn depth. Int Wound J 2024; 21:e14681. [PMID: 38272799 PMCID: PMC10805628 DOI: 10.1111/iwj.14681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 01/03/2024] [Indexed: 01/27/2024] Open
Abstract
Currently, the clinical diagnosis of burn depth primarily relies on physicians' judgements based on patients' symptoms and physical signs, particularly the morphological characteristics of the wound. This method highly depends on individual doctors' clinical experience, proving challenging for less experienced or primary care physicians, with results often varying from one practitioner to another. Therefore, scholars have been exploring an objective and quantitative auxiliary examination technique to enhance the accuracy and consistency of burn depth diagnosis. Non-invasive medical imaging technology, with its significant advantages in examining tissue surface morphology, blood flow in deep and changes in structure and composition, has become a hot topic in burn diagnostic technology research in recent years. This paper reviews various non-invasive medical imaging technologies that have shown potential in burn depth diagnosis. These technologies are summarized and synthesized in terms of imaging principles, current research status, advantages and limitations, aiming to provide a reference for clinical application or research for burn specialists.
Collapse
Affiliation(s)
- Hang Li
- Department of Burns and Plastic SurgerySecond Affiliated Hospital of Air Force Medical UniversityXi'anP.R. China
| | - Qilong Bu
- Bioinspired Engineering and Biomechanics CenterXi'an Jiaotong UniversityXi'anP.R. China
| | - Xufeng Shi
- Department of Burns and Plastic SurgerySecond Affiliated Hospital of Air Force Medical UniversityXi'anP.R. China
| | - Xiayu Xu
- Bioinspired Engineering and Biomechanics CenterXi'an Jiaotong UniversityXi'anP.R. China
| | - Jing Li
- Department of Burns and Plastic SurgerySecond Affiliated Hospital of Air Force Medical UniversityXi'anP.R. China
| |
Collapse
|
11
|
Liu HL, Yuan Y, Han L, Bi Y, Yu WY, Yu Y. Wide dynamic range measurement of blood flow in vivo using laser speckle contrast imaging. J Biomed Opt 2024; 29:016009. [PMID: 38283936 PMCID: PMC10821768 DOI: 10.1117/1.jbo.29.1.016009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/04/2024] [Accepted: 01/08/2024] [Indexed: 01/30/2024]
Abstract
Significance Laser speckle contrast imaging (LSCI) is a real-time wide-field technique that is applied to visualize blood flow in biomedical applications. However, there is currently a lack of relevant research to demonstrate that it can measure velocities over a wide dynamic range (WDR), which is critical for monitoring much higher and more pulsatile blood flow in larger size myocardial vessels, such as the coronary artery bypass graft, and visualizing the spatio-temporal evolution of myocardial blood flow perfusion in cardiac surgery. Aim We aim to demonstrate that the LSCI technique enables measuring velocities over a WDR from phantom experiments to animal experiments. In addition, LSCI is preliminarily applied to imaging myocardial blood flow distribution in vivo on rabbits. Approach Phantom and animal experiments are performed to verify that the LSCI method has the ability to measure blood velocities over a wide range. Our method is also validated by transit time flow measurement, which is the gold standard for blood flow measurement in cardiac surgery. Results Our method is demonstrated to measure the blood flow over a wide range from 0.2 to 635 mm / s . To validate the phantom results, the varying blood flow rate from 0 to 320 mm / s is detected in the rat carotid artery. Additionally, our technique also obtains blood flow maps of different myocardial vessels, such as superficial large/small veins, veins surrounded by fat, and myocardial deeper arteriole. Conclusions Our study has the potential to visualize the spatio-temporal evolution of myocardial perfusion in coronary artery bypass grafting, which would be of great benefit for future research in the life sciences and clinical medicine.
Collapse
Affiliation(s)
- Hong Li Liu
- Beijing Anzhen Hospital of Capital Medical University, Department of Cardiovascular Surgery, Beijing, China
| | - Yuan Yuan
- Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Center of Applied Laser, Beijing, China
| | - Li Han
- Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Center of Applied Laser, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yong Bi
- Chinese Academy of Sciences, Technical Institute of Physics and Chemistry, Center of Applied Laser, Beijing, China
| | - Wen Yuan Yu
- Beijing Anzhen Hospital of Capital Medical University, Department of Cardiovascular Surgery, Beijing, China
| | - Yang Yu
- Beijing Anzhen Hospital of Capital Medical University, Department of Cardiovascular Surgery, Beijing, China
| |
Collapse
|
12
|
Dijkstra A, Guven G, van Baar ME, Trommel N, Hofland HWC, Kuijper TM, Ince C, Van der Vlies CH. Laser speckle contrast imaging, an alternative to laser doppler imaging in clinical practice of burn wound care derivation of a color code. Burns 2023; 49:1907-1915. [PMID: 37863755 DOI: 10.1016/j.burns.2023.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 03/22/2023] [Accepted: 04/28/2023] [Indexed: 10/22/2023]
Abstract
OBJECTIVE To develop a color code and to investigate the validity of Laser Speckle Contrast Imaging (LSCI) for measuring burn wound healing potential (HP) in burn patients as compared to the reference standard Laser Doppler Imaging (LDI). METHOD A prospective, observational, cohort study was conducted in adult patients with acute burn wounds. The relationship between mean flux measured with LDI and mean perfusion units (PU) measured with LSCI was expressed in a regression formula. Measurements were performed between 2 and 5 days after the burn wound. The creation of a LSCI color code was done by mapping the clinically validated color code of the LDI to the corresponding values on the LSCI scale. To assess validity of the LSCI, the ability of the LSCI to discriminate between HP < 14 and ≥ 14 days and HP < 21 and original ≥ 21 days according to the LDI reference standard was evaluated, with calculation of receiver operating characteristics (ROC) curves. RESULTS A total of 50 patients were included with a median age of 40 years and total body surface area burned of 6%. LSCI values of 143 PU and 113 PU were derived as the cut-off values for the need of conservative treatment (HP < 14 and ≥ 14 days) resp. surgical closure (HP < 21 and ≥ 21 days). These LSCI cut off values showed a good discrimination between HP 14 days versus ≥ 14 days (Area Under Curve (AUC)= 0.89; sensitivity 85% and specificity = 82%) and a good discrimination between HP 21 days versus ≥ 21 days (AUC of 0.89, sensitivity 81% and specificity 88%). CONCLUSION This is the first study in which a color code for the LSCI in adult clinical burn patients has been developed. Our study reconfirms the good performance of the LSCI for prediction of burn wound healing potential. This provides additional evidence for the potential value of the LSCI in specialized burn care.
Collapse
Affiliation(s)
- Annemieke Dijkstra
- van Weel Bethesda Hospital, Department of Intensive Care, Dirksland, the Netherlands.
| | - Goksel Guven
- Hacettepe University Faculty of Medicine, Department of Intensive Care, Ankara, Turkey
| | | | - Nicole Trommel
- Maasstad Hospital, Burn Centre, Rotterdam, the Netherlands
| | | | - T Martijn Kuijper
- Maasstad Hospital, Department of Rheumatology, Rotterdam, the Netherlands
| | - Can Ince
- Erasmus Medical Center, Department of Translational Intensive Care, Rotterdam, the Netherlands
| | | |
Collapse
|
13
|
Owoso T, Kankam HKN, Abdulsalam A, Lewis D. The Use of Laser Doppler Imaging in Nitric Acid Burns: A Case Report and Literature Review. J Burn Care Res 2023; 44:1440-1444. [PMID: 36987869 PMCID: PMC10628518 DOI: 10.1093/jbcr/irad044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Indexed: 03/30/2023]
Abstract
Laser Doppler imaging (LDI) technology has been validated to assess thermal burn depth by predicting wound healing potential. However, there is no clear evidence for its use in chemical burns. We present a case of an 8% total burn surface area (TBSA) nitric acid burn following an industrial accident, in an otherwise healthy 36-year-old man. LDI assessment was suggestive of poor healing potential of >21 days, warranting surgical management. However, conservative management was opted for based on clinical assessment as the wound eschar appeared thin and more consistent with epithelial staining. Patient follow-up confirmed a total burn healing time of two months, suggesting that the LDI assessment was accurate. A comprehensive literature review was performed using the MEDLINE (PubMed) database to identify animal or clinical studies evaluating the efficacy of LDI in chemical burns. A qualitative synthesis of our findings is presented. We identified two experimental studies in porcine models with sulfur mustard burns, each confirming the accuracy of LDI assessment when compared to the histopathology findings. Limited experimental animal studies on the use of LDI suggest similar validity in chemical burns, and this correlates with the clinical outcome in this case. However, this alone is insufficient to prove its validity and define its role in the assessment of chemical burns. Clinical trials are required to further assess and define the parameters of LDI use and efficacy in this context.
Collapse
Affiliation(s)
- Toluwaniyin Owoso
- Department of Burns and Plastic Surgery, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Hadyn K N Kankam
- Department of Burns and Plastic Surgery, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Abdulrazak Abdulsalam
- Department of Burns and Plastic Surgery, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Darren Lewis
- Department of Burns and Plastic Surgery, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| |
Collapse
|
14
|
González Olmos A, Zilpelwar S, Sunil S, Boas DA, Postnov DD. Optimizing the precision of laser speckle contrast imaging. Sci Rep 2023; 13:17970. [PMID: 37864006 PMCID: PMC10589309 DOI: 10.1038/s41598-023-45303-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 10/18/2023] [Indexed: 10/22/2023] Open
Abstract
Laser speckle contrast imaging (LSCI) is a rapidly developing technology broadly applied for the full-field characterization of tissue perfusion. Over the recent years, significant advancements have been made in interpreting LSCI measurements and improving the technique's accuracy. On the other hand, the method's precision has yet to be studied in detail, despite being as important as accuracy for many biomedical applications. Here we combine simulation, theory and animal experiments to systematically evaluate and re-analyze the role of key factors defining LSCI precision-speckle-to-pixel size ratio, polarisation, exposure time and camera-related noise. We show that contrary to the established assumptions, smaller speckle size and shorter exposure time can improve the precision, while the camera choice is less critical and does not affect the signal-to-noise ratio significantly.
Collapse
Affiliation(s)
| | - Sharvari Zilpelwar
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Smrithi Sunil
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - David A Boas
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Dmitry D Postnov
- Department of Clinical Medicine, Aarhus University, 8200, Aarhus, Denmark.
| |
Collapse
|
15
|
Katz MS, Ooms M, Winnand P, Heitzer M, Bock A, Kniha K, Hölzle F, Modabber A. Evaluation of perfusion parameters of gingival inflammation using laser Doppler flowmetry and tissue spectrophotometry- a prospective comparative clinical study. BMC Oral Health 2023; 23:761. [PMID: 37838702 PMCID: PMC10576369 DOI: 10.1186/s12903-023-03507-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Accepted: 10/08/2023] [Indexed: 10/16/2023] Open
Abstract
BACKGROUND The aim of this study was to determine the values of different perfusion parameters- such as oxygen saturation, the relative amount of hemoglobin, and blood flow- in healthy subjects compared to patients with gingivitis as a non-invasive measurement method. METHODS A total of 114 subjects were enrolled in this study and separated into subjects with gingivitis (50) and without gingivitis (64) based on clinical examination. Gingival perfusion was measured at 22 points in the maxilla and mandible using laser Doppler flowmetry and tissue spectrophotometry (LDF-TS) with the "oxygen to see" device. All patients underwent measurement of gingival perfusion, followed by the clinical evaluation (measurement of probing depths, evaluation of bleeding on probing, plaque level, and biotype). Perfusion parameters were compared between the groups, associations between the non-invasive and clinical measurements were analyzed, and theoretical optimal cut-off values for predicting gingivitis were calculated with receiver operating characteristics. RESULTS The mean oxygen saturation, mean relative amount of hemoglobin, and mean blood flow all significantly differed between the groups with and without gingivitis (p = 0.005, p < 0.001, and p < 0.001, respectively). The cut-off value for predicting gingivitis was > 40 AU (p < 0.001; sensitivity 0.90, specificity 0.67). CONCLUSIONS As a non-invasive method, LDF-TS can help determine gingival hyperemia. Flow values above 40 AU indicate a higher risk of hyperemia, which can be associated with inflammation. The LDF-TS method can be used for the objective evaluation of perfusion parameters during routine examinations and can signal the progression of hyperperfusion before any change in clinical parameters is observed. TRIAL REGISTRATION All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the institutional Clinical Research Ethics Committee (Ethik-Kommission der Medizinischen Fakultät der RWTH Aachen, Decision Number 286/20) and retrospectively registered by the German Clinical Trials Register (File Number DRKS00024048, registered on the 15th of October 2021).
Collapse
Affiliation(s)
- Marie Sophie Katz
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany.
| | - Mark Ooms
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| | - Philipp Winnand
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| | - Marius Heitzer
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| | - Anna Bock
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| | - Kristian Kniha
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| | - Frank Hölzle
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| | - Ali Modabber
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelstraße 30, Aachen, 52074, Germany
| |
Collapse
|
16
|
Rozo A, Miskovic V, Rose T, Keersebilck E, Iorio C, Varon C. A Deep Learning Image-to-Image Translation Approach for a More Accessible Estimator of the Healing Time of Burns. IEEE Trans Biomed Eng 2023; 70:2886-2894. [PMID: 37067977 DOI: 10.1109/tbme.2023.3267600] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
OBJECTIVE An accurate and timely diagnosis of burn severity is critical to ensure a positive outcome. Laser Doppler imaging (LDI) has become a very useful tool for this task. It measures the perfusion of the burn and estimates its potential healing time. LDIs generate a 6-color palette image, with each color representing a healing time. This technique has very high costs associated. In resource-limited areas, such as low- and middle-income countries or remote locations like space, where access to specialized burn care is inadequate, more affordable and portable tools are required. This study proposes a novel image-to-image translation approach to estimate burn healing times, using a digital image to approximate the LDI. METHODS This approach consists of a U-net architecture with a VGG-based encoder and applies the concept of ordinal classification. Paired digital and LDI images of burns were collected. The performance was evaluated with 10-fold cross-validation, mean absolute error (MAE), and color distribution differences between the ground truth and the estimated LDI. RESULTS Results showed a satisfactory performance in terms of low MAE ( 0.2370 ±0.0086). However, the unbalanced distribution of colors in the data affects this performance. SIGNIFICANCE This novel and unique approach serves as a basis for developing more accessible support tools in the burn care environment in resource-limited areas.
Collapse
|
17
|
Fang Y, van Ooijen L, Ambagtsheer G, Nikolaev AV, Clahsen-van Groningen MC, Dankelman J, de Bruin RWF, Minnee RC. Real-time laser speckle contrast imaging measurement during normothermic machine perfusion in pretransplant kidney assessment. Lasers Surg Med 2023; 55:784-793. [PMID: 37555246 DOI: 10.1002/lsm.23715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 07/31/2023] [Accepted: 07/31/2023] [Indexed: 08/10/2023]
Abstract
OBJECTIVES Normothermic machine perfusion (NMP) provides a platform for pre-transplant kidney quality assessment that is essential for the use of marginal donor kidneys. Laser speckle contrast imaging (LSCI) presents distinct advantages as a real-time and noncontact imaging technique for measuring microcirculation. In this study, we aimed to assess the value of LSCI in visualizing renal cortical perfusion and investigate the additional value of dual-side LSCI measurements compared to single aspect measurement during NMP. METHODS Porcine kidneys were obtained from a slaughterhouse and then underwent NMP. LSCI was used to measure one-sided cortical perfusion in the first 100 min of NMP. Thereafter, the inferior renal artery branch was occluded to induce partial ischemia and LSCI measurements on both ventral and dorsal sides were performed. RESULTS LSCI fluxes correlated linearly with the renal blood flow (R2 = 0.90, p < 0.001). After renal artery branch occlusion, absence of renal cortical perfusion could be visualized and semiquantified by LSCI. The overall ischemic area percentage of the ventral and dorsal sides was comparable (median interquartile range [IQR], 38 [24-43]% vs. 29 [17-46]%, p = 0.43), but heterogenous patterns between the two aspects were observed. There was a significant difference in oxygen consumption (mean ± standard deviation [SD], 2.57 ± 0.63 vs. 1.83 ± 0.49 mLO2 /min/100 g, p < 0.001), urine output (median [IQR], 1.3 [1.1-1.7] vs. 0.8 [0.6-1.3] mL/min, p < 0.05), lactate dehydrogenase (mean ± SD, 768 ± 370 vs. 905 ± 401 U/L, p < 0.05) and AST (mean ± SD, 352 ± 285 vs. 462 ± 383 U/L, p < 0.01) before and after renal artery occlusion, while no significant difference was found in creatinine clearance, fractional excretion of sodium, total sodium reabsorption and histological damage. CONCLUSIONS LSCI fluxes correlated linearly with renal blood flow during NMP. Renal cortical microcirculation and absent perfusion can be visualized and semiquantified by LSCI. It provides a relative understanding of perfusion levels, allowing for a qualitative comparison between regions in the kidney. Dual-side LSCI measurements are of added value compared to single aspect measurement and renal function markers.
Collapse
Affiliation(s)
- Yitian Fang
- Department of Surgery, Division of HPB and Transplant Surgery, Transplant Institute, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Lisanne van Ooijen
- Department of Biomechanical Engineering, Delft University of Technology, Delft, the Netherlands
| | - Gisela Ambagtsheer
- Department of Surgery, Division of HPB and Transplant Surgery, Transplant Institute, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Anton V Nikolaev
- Department of Cardiology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Marian C Clahsen-van Groningen
- Department of Pathology and Clinical Bioinformatics, Erasmus Medical Center, Rotterdam, the Netherlands
- Institute of Experimental and Systems Biology, RWTH Aachen University, Aachen, Germany
| | - Jenny Dankelman
- Department of Biomechanical Engineering, Delft University of Technology, Delft, the Netherlands
| | - Ron W F de Bruin
- Department of Surgery, Division of HPB and Transplant Surgery, Transplant Institute, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Robert C Minnee
- Department of Surgery, Division of HPB and Transplant Surgery, Transplant Institute, Erasmus Medical Center, Rotterdam, the Netherlands
| |
Collapse
|
18
|
Ito Y, Ishii T, Yamazaki S, Yoshida A, Nagaya K, Saijo Y. Evaluation of temperature-dependent fluctuations in skin microcirculation flow using a light-emitting diode based photoacoustic imaging device. J Clin Monit Comput 2023; 37:1361-1367. [PMID: 37166692 DOI: 10.1007/s10877-023-01026-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 04/24/2023] [Indexed: 05/12/2023]
Abstract
PURPOSE Skin microvessels maintain temperature homeostasis by contracting and dilating upon exposure to changes in temperature. Under general anesthesia, surgical invasiveness, including incisions and coagulation, and the effects of anesthetics may cause variations in the threshold temperature, leading to the constriction and dilation of cutaneous blood vessels. Therefore, studies on skin microvascular circulation are necessary to develop appropriate interventions for complications during surgery. METHODS We visualized and quantified skin microcirculatory fluctuations associated with temperature variations using a light-emitting diode photoacoustic imaging (LED-PAI) device. The hands of ten healthy volunteers were stressed with four different water temperatures [25℃ (Control), 15℃ (Cold1), 40℃ (Warm), and 15℃ (Cold2)]. The photoacoustic images of the fingers were taken under each condition, and the microvascular flow owing to temperature stress was quantified as the area of photoacoustic signal (S) in each image. The S values were compared with the variations in blood flow (Q) measured by laser Doppler flowmetry (LDF). RESULTS The correlation between Q and S according to the 40 measurements was r = 0.45 (p<0.01). In addition, the values of S under each stress condition were as follows: Scontrol = 10,826 ± 3364 pixels, Scold1 = 8825 ± 2484 pixels, Swarm = 13,369 ± 3001 pixels, and Scold2 = 8838 ± 1892 pixels; the differences were significant. The LDF blood flow (Q) showed similar changes among conditions. CONCLUSION These findings suggest that the LED-PAI device could be an option for evaluating microcirculation in association with changes in temperature.
Collapse
Affiliation(s)
- Yosuke Ito
- Graduate School of Medicine, Tohoku University, Sendai, Miyagi, 980-8575, Japan.
- Department of Anesthesia, Tohoku Medical and Pharmaceutical University Hospital, Sendai, Miyagi, 983-8512, Japan.
| | - Takuro Ishii
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Miyagi, 980-8579, Japan
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Miyagi, 980-8578, Japan
| | - Shin Yamazaki
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Miyagi, 980-8579, Japan
| | - Akiko Yoshida
- Department of Anesthesia, Tohoku Medical and Pharmaceutical University Hospital, Sendai, Miyagi, 983-8512, Japan
| | - Kei Nagaya
- Department of Anesthesia, Tohoku Medical and Pharmaceutical University Hospital, Sendai, Miyagi, 983-8512, Japan
| | - Yoshifumi Saijo
- Graduate School of Medicine, Tohoku University, Sendai, Miyagi, 980-8575, Japan
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Miyagi, 980-8579, Japan
| |
Collapse
|
19
|
Liu YZ, Mehrotra S, Buharin VE, Marois M, Nwaiwu CA, Wilson EB, Kim PCW. Dye-Less Perfusion Quantification of Porcine Gastric Conduit with Laser Speckle Contrast Imaging and Laser Doppler Imaging. J Gastrointest Surg 2023; 27:1947-1949. [PMID: 37227609 DOI: 10.1007/s11605-023-05708-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/01/2023] [Indexed: 05/26/2023]
Affiliation(s)
- Yao Z Liu
- Department of Surgery, Brown University, Providence, RI, USA
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Saloni Mehrotra
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
- Department of Surgery, University at Buffalo, NY, Buffalo, USA
| | - Vasiliy E Buharin
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Mikael Marois
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Chibueze A Nwaiwu
- Department of Surgery, Brown University, Providence, RI, USA
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA
| | - Erik B Wilson
- University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Peter C W Kim
- Department of Surgery, Brown University, Providence, RI, USA.
- Activ Surgical Inc., 30 Thomson Place, 2nd Floor, MA, 02210, Boston, USA.
| |
Collapse
|
20
|
Lin YJ, Lee CC, Huang TW, Hsu WC, Wu LW, Lin CC, Hsiu H. Using Arterial Pulse and Laser Doppler Analyses to Discriminate between the Cardiovascular Effects of Different Running Levels. Sensors (Basel) 2023; 23:3855. [PMID: 37112196 PMCID: PMC10142346 DOI: 10.3390/s23083855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/04/2023] [Accepted: 04/09/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND AND AIMS Running can induce advantageous cardiovascular effects such as improved arterial stiffness and blood-supply perfusion. However, the differences between the vascular and blood-flow perfusion conditions under different levels of endurance-running performance remains unclear. The present study aimed to assess the vascular and blood-flow perfusion conditions among 3 groups (44 male volunteers) according to the time taken to run 3 km: Level 1, Level 2, and Level 3. METHODS The radial blood pressure waveform (BPW), finger photoplethygraphy (PPG), and skin-surface laser-Doppler flowmetry (LDF) signals of the subjects were measured. Frequency-domain analysis was applied to BPW and PPG signals; time- and frequency-domain analyses were applied to LDF signals. RESULTS Pulse waveform and LDF indices differed significantly among the three groups. These could be used to evaluate the advantageous cardiovascular effects provided by long-term endurance-running training, such as vessel relaxation (pulse waveform indices), improvement in blood supply perfusion (LDF indices), and changes in cardiovascular regulation activities (pulse and LDF variability indices). Using the relative changes in pulse-effect indices, we achieved almost perfect discrimination between Level 3 and Level 2 (AUC = 0.878). Furthermore, the present pulse waveform analysis could also be used to discriminate between the Level-1 and Level-2 groups. CONCLUSIONS The present findings contribute to the development of a noninvasive, easy-to-use, and objective evaluation technique for the cardiovascular benefits of prolonged endurance-running training.
Collapse
Affiliation(s)
- Yi-Jia Lin
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Chia-Chien Lee
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Tzu-Wei Huang
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Wei-Chun Hsu
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Li-Wei Wu
- Division of Family Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, School of Medicine, National Defense Medical Center, Taipei 114, Taiwan
- Health Management Center, Department of Family and Community Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
| | - Chen-Chun Lin
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
- College of Applied Science, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Hsin Hsiu
- Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| |
Collapse
|
21
|
Chizari A, Tsong W, Knop T, Steenbergen W. Prediction of motion artifacts caused by translation in handheld laser speckle contrast imaging. J Biomed Opt 2023; 28:046005. [PMID: 37082096 PMCID: PMC10112282 DOI: 10.1117/1.jbo.28.4.046005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 03/24/2023] [Indexed: 05/03/2023]
Abstract
Significance In handheld laser speckle contrast imaging (LSCI), motion artifacts (MA) are inevitable. Suppression of MA leads to a valid and objective assessment of tissue perfusion in a wide range of medical applications including dermatology and burns. Our study shines light on the sources of these artifacts, which have not yet been explored. We propose a model based on optical Doppler effect to predict speckle contrast drop as an indication of MA. Aim We aim to theoretically model MA when an LSCI system measuring on static scattering media is subject to translational displacements. We validate the model using both simulation and experiments. This is the crucial first step toward creating robustness against MA. Approach Our model calculates optical Doppler shifts in order to predict intensity correlation function and contrast of the time-integrated intensity as functions of applied speed based on illumination and detection wavevectors. To validate the theoretical predictions, computer simulation of the dynamic speckles has been carried out. Then experiments are performed by both high-speed and low-framerate imaging. The employed samples for the experiments are a highly scattering matte surface and a Delrin plate of finite scattering level in which volume scattering occurs. Results An agreement has been found between theoretical prediction, simulation, and experimental results of both intensity correlation functions and speckle contrast. Coefficients in the proposed model have been linked to the physical parameters according to the experimental setups. Conclusions The proposed model provides a quantitative description of the influence of the types of illumination and media in the creation of MA. The accurate prediction of MA caused by translation based on Doppler shifts makes our model suitable to study the influence of rotation. Also the model can be extended for the case of dynamic media, such as live tissue.
Collapse
Affiliation(s)
- Ata Chizari
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
- Address all correspondence to Ata Chizari,
| | - Wilson Tsong
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Tom Knop
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, Technical Medical Centre, Faculty of Science and Technology, Biomedical Photonic Imaging Group, Enschede, The Netherlands
| |
Collapse
|
22
|
Tang Y, Xu F, Lei P, Li G, Tan Z. Spectral analysis of laser speckle contrast imaging and infrared thermography to assess skin microvascular reactive hyperemia. Skin Res Technol 2023; 29:e13308. [PMID: 37113098 PMCID: PMC10234160 DOI: 10.1111/srt.13308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 02/25/2023] [Indexed: 04/29/2023]
Abstract
BACKGROUND Post-occlusive reactive hyperemia (PORH) test with signal spectral analysis coupled provides potential indicators for the assessment of microvascular functions. OBJECTIVE The objective of this study is to investigate the variations of skin blood flow and temperature spectra in the PORH test. Furthermore, to quantify the oscillation amplitude response to occlusion within different frequency ranges. MATERIALS AND METHODS Ten healthy volunteers participated in the PORH test and their hand skin temperature and blood flow images were captured by infrared thermography (IRT) and laser speckle contrast imaging (LSCI) system, respectively. Extracted signals from selected areas were then transformed into the time-frequency space by continuous wavelet transform for cross-correlation analysis and oscillation amplitude response comparisons. RESULTS The LSCI and IRT signals extracted from fingertips showed stronger hyperemia response and larger oscillation amplitude compared with other areas, and their spectral cross-correlations decreased with frequency. According to statistical analysis, their oscillation amplitudes in the PORH stage were obviously larger than the baseline stage within endothelial, neurogenic, and myogenic frequency ranges (p < 0.05), and their quantitative indicators of oscillation amplitude response had high linear correlations within endothelial and neurogenic frequency ranges. CONCLUSION Comparisons of IRT and LSCI techniques in recording the reaction to the PORH test were made in both temporal and spectral domains. The larger oscillation amplitudes suggested enhanced endothelial, neurogenic, and myogenic activities in the PORH test. We hope this study is also significant for investigations of response to the PORH test by other non-invasive techniques.
Collapse
Affiliation(s)
- Yuanliang Tang
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Fei Xu
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Peng Lei
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Guixiang Li
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| | - Zhongwei Tan
- Institute of Biological and Medical EngineeringGuangdong Academy of SciencesGuangzhouChina
- National Engineering Research Center for Healthcare DevicesGuangzhouChina
| |
Collapse
|
23
|
Sullender CT, Santorelli A, Richards LM, Mannava PK, Smith C, Dunn AK. Using pressure-driven flow systems to evaluate laser speckle contrast imaging. J Biomed Opt 2023; 28:036003. [PMID: 36915371 PMCID: PMC10007838 DOI: 10.1117/1.jbo.28.3.036003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
SIGNIFICANCE Microfluidic flow phantom studies are commonly used for characterizing the performance of laser speckle contrast imaging (LSCI) instruments. The selection of the flow control system is critical for the reliable generation of flow during testing. The majority of recent LSCI studies using microfluidics used syringe pumps for flow control. AIM We quantified the uncertainty in flow generation for a syringe pump and a pressure-regulated flow system. We then assessed the performance of both LSCI and multi-exposure speckle imaging (MESI) using the pressure-regulated flow system across a range of flow speeds. APPROACH The syringe pump and pressure-regulated flow systems were evaluated during stepped flow profile experiments in a microfluidic device using an inline flow sensor. The uncertainty associated with each flow system was calculated and used to determine the reliability for instrument testing. The pressure-regulated flow system was then used to characterize the relative performance of LSCI and MESI during stepped flow profile experiments while using the inline flow sensor as reference. RESULTS The pressure-regulated flow system produced much more stable and reproducible flow outputs compared to the syringe pump. The expanded uncertainty for the syringe pump was 8 to 20 × higher than that of the pressure-regulated flow system across the tested flow speeds. Using the pressure-regulated flow system, MESI outperformed single-exposure LSCI at all flow speeds and closely mirrored the flow sensor measurements, with average errors of 4.6 % ± 2.6 % and 15.7 % ± 4.6 % , respectively. CONCLUSIONS Pressure-regulated flow systems should be used instead of syringe pumps when assessing the performance of flow measurement techniques with microfluidic studies. MESI offers more accurate relative flow measurements than traditional LSCI across a wide range of flow speeds.
Collapse
Affiliation(s)
- Colin T. Sullender
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Adam Santorelli
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Lisa M. Richards
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Pawan K. Mannava
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Christopher Smith
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| | - Andrew K. Dunn
- The University of Texas at Austin, Department of Biomedical Engineering, Austin, Texas, United States
| |
Collapse
|
24
|
Hultman M, Larsson M, Strömberg T, Fredriksson I. Speed-resolved perfusion imaging using multi-exposure laser speckle contrast imaging and machine learning. J Biomed Opt 2023; 28:036007. [PMID: 36950019 PMCID: PMC10027009 DOI: 10.1117/1.jbo.28.3.036007] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 02/27/2023] [Indexed: 05/19/2023]
Abstract
SIGNIFICANCE Laser speckle contrast imaging (LSCI) gives a relative measure of microcirculatory perfusion. However, due to the limited information in single-exposure LSCI, models are inaccurate for skin tissue due to complex effects from e.g. static and dynamic scatterers, multiple Doppler shifts, and the speed-distribution of blood. It has been demonstrated how to account for these effects in laser Doppler flowmetry (LDF) using inverse Monte Carlo (MC) algorithms. This allows for a speed-resolved perfusion measure in absolute units %RBC × mm/s, improving the physiological interpretation of the data. Until now, this has been limited to a single-point LDF technique but recent advances in multi-exposure LSCI (MELSCI) enable the analysis in an imaging modality. AIM To present a method for speed-resolved perfusion imaging in absolute units %RBC × mm/s, computed from multi-exposure speckle contrast images. APPROACH An artificial neural network (ANN) was trained on a large simulated dataset of multi-exposure contrast values and corresponding speed-resolved perfusion. The dataset was generated using MC simulations of photon transport in randomized skin models covering a wide range of physiologically relevant geometrical and optical tissue properties. The ANN was evaluated on in vivo data sets captured during an occlusion provocation. RESULTS Speed-resolved perfusion was estimated in the three speed intervals 0 to 1 mm / s , 1 to 10 mm / s , and > 10 mm / s , with relative errors 9.8%, 12%, and 19%, respectively. The perfusion had a linear response to changes in both blood tissue fraction and blood flow speed and was less affected by tissue properties compared with single-exposure LSCI. The image quality was subjectively higher compared with LSCI, revealing previously unseen macro- and microvascular structures. CONCLUSIONS The ANN, trained on modeled data, calculates speed-resolved perfusion in absolute units from multi-exposure speckle contrast. This method facilitates the physiological interpretation of measurements using MELSCI and may increase the clinical impact of the technique.
Collapse
Affiliation(s)
- Martin Hultman
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
- Perimed AB, Stockholm, Sweden
- Address all correspondence to Martin Hultman,
| | - Marcus Larsson
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Tomas Strömberg
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
| | - Ingemar Fredriksson
- Linköping University, Department of Biomedical Engineering, Linköping, Sweden
- Perimed AB, Stockholm, Sweden
| |
Collapse
|
25
|
Krechina EK, Braylovskaia TV, Verbo EV, Abaev ZM, Deniev AM, Khamraeva NT. [Assessment of microhaemodynamics and oxygenation in tissues after the vestibuloplasty with the use of a free dermal autograft in patients after the reconstructive jaw surgery with the use of the revascularized autografts]. Stomatologiia (Mosk) 2023; 102:25-30. [PMID: 38096391 DOI: 10.17116/stomat202310206225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Purpose of the study: to study the features of microhaemodynamics and oxygenation in soft tissues in the area of the plastically reconstructed jaw after the vestibuloplasty. MATERIALS AND METHODS The study included 40 patients aged 20 to 65 (21 males and 19 females). The patients were divided into two groups: I group (14 patients) - patients after reconstructive surgery with the use a fibula autograft without the inclusion of a musculocutaneous «islet»; II group (26 patients) - patients after reconstructive surgery with the use a fibula autograft with the inclusion of a musculocutaneous «islet». To correct the prosthetic bed soft tissues, all patients underwent vestibuloplasty with the use of a free dermal autograft. To study microcirculation in tissues, the laser Doppler flowmetry (LDF) method was used. Microcirculation status was assessed by microcirculation index characterizing the level of tissue blood flow; parameter «σ,» which determines the oscillability of the flow of red blood cells and by coefficient of variation, characterizing vasomotor activity of microvessels. According to the Wavelet analysis of LDF-grams the blood flow bypass was determined. An oxygenation study was carried out in the tissues of the plastically restored jaw by optical tissue oximetry, the results of which determined the oxygenation index and the specific oxygen consumption index. RESULTS According to LDF data after vestibuloplasty, it was found that in I group, the microcirculation in soft tissues of the plastically reconstructed jaw restored in 21 days, and in II group in 2 months, which persisted at 6 months. In I group, the level of oxygenation and specific oxygen consumption normalized in 21 days, and in II group in 2 months, which persisted at 6 months. CONCLUSION Based on the results of this functional study, it was found that before vestibuloplasty microcirculation and oxygenation indices in II group patients were lower than those in I group patients. After vestibuloplasty with the use of a free dermal autograft, microcirculation indices in II group patients restored in 2 months, while in I group patients those indices restored in 21 days.
Collapse
Affiliation(s)
- E K Krechina
- Central Research Institute of Dentistry and Maxillofacial Surgery of the Ministry of Healthcare of Russia, Moscow, Russia
| | - T V Braylovskaia
- Central Research Institute of Dentistry and Maxillofacial Surgery of the Ministry of Healthcare of Russia, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation, Moscow, Russia
| | - E V Verbo
- JSC «Institute of Plastic Surgery and Cosmetology, » Moscow, Russia
| | - Z M Abaev
- I.M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation, Moscow, Russia
| | - A M Deniev
- Central Research Institute of Dentistry and Maxillofacial Surgery of the Ministry of Healthcare of Russia, Moscow, Russia
| | - N T Khamraeva
- Central Research Institute of Dentistry and Maxillofacial Surgery of the Ministry of Healthcare of Russia, Moscow, Russia
| |
Collapse
|
26
|
Zherebtsov E, Kozlov I, Dremin V, Bykov A, Dunaev A, Meglinski I. Diagnosis of Skin Vascular Complications Revealed by Time-Frequency Analysis and Laser Doppler Spectrum Decomposition. IEEE Trans Biomed Eng 2023; 70:3-14. [PMID: 35679373 DOI: 10.1109/tbme.2022.3181126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Nowadays, photonics-based techniques are used extensively in various applications, including functional clinical diagnosis, progress monitoring in treatment, and provision of metrological control. In fact, in the frame of practical implementation of optical methods, such as laser Doppler flowmetry (LDF), the qualitative interpretation and quantitative assessment of the detected signal remains vital and urgently required. In the conventional LDF approach, the key measured parameters, index of microcirculation and perfusion rate, are proportional to an averaged concentration of red blood cells (RBC) and their average velocity within a diagnostic volume. These quantities compose mixed signals from different vascular beds with a range of blood flow velocities and are typically expressed in relative units. In the current paper we introduce a new signal processing approach for the decomposition of LDF power spectra in terms of ranging blood flow distribution by frequency series. The developed approach was validated in standard occlusion tests conducted on healthy volunteers, and applied to investigate the influence of local pressure rendered by a probe on the surface of the skin. Finally, in limited clinical trials, we demonstrate that the approach can significantly improve the diagnostic accuracy of detection of microvascular changes in the skin of the feet in patients with Diabetes Mellitus type 2, as well as age-specific changes. The results obtained show that the developed approach of LDF signal decomposition provides essential new information about blood flow and blood microcirculation and has great potential in the diagnosis of vascular complications associated with various diseases.
Collapse
|
27
|
Bode FI, Nastase I. Numerical Investigation of Very Low Reynolds Cross Orifice Jet for Personalized Ventilation Applications in Aircraft Cabins. Int J Environ Res Public Health 2022; 20:740. [PMID: 36613062 PMCID: PMC9819846 DOI: 10.3390/ijerph20010740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
This study focuses on the numerical analysis of a challenging issue involving the regulation of the human body's microenvironment through personalized ventilation. We intended to first concentrate on the main flow, namely, the personalized ventilation jet, before connecting the many interacting components that are impacting this microenvironment (human body plume, personalized ventilation jet, and the human body itself as a solid obstacle). Using the laminar model and the large eddy simulation (LES) model, the flow field of a cross-shaped jet with very low Reynolds numbers is examined numerically. The related results are compared to data from laser doppler velocimetry (LDV) and particle image velocimetry (PIV) for a reference jet design. The major goal of this study is to evaluate the advantages and disadvantages of the CFD approach for simulating the key features of the cross-shaped orifice jet flow. It was discovered that the laminar model overestimated the global jet volumetric flow rate and the flow expansion. LES looks more suitable for the numerical prediction of such dynamic integral quantities. In light of the computational constraints, it quite accurately mimics the mean flow behavior in the first ten equivalent diameters from the orifice, where the mesh grid was extremely finely tuned. From the perspective of the intended application, the streamwise velocity distributions, streamwise velocity decay, and volumetric flow rate anticipated by the LES model are rather well reproduced.
Collapse
Affiliation(s)
- Florin Ioan Bode
- Mechanical Engineering Department, Technical University of Cluj-Napoca, Muncii Boulevard Nr. 103-105, D03, 400114 Cluj-Napoca, Romania
- Building Services Department, CAMBI, Technical University of Civil Engineering in Bucharest, 66 Avenue Pache Protopopescu, 020396 Bucharest, Romania
| | - Ilinca Nastase
- Building Services Department, CAMBI, Technical University of Civil Engineering in Bucharest, 66 Avenue Pache Protopopescu, 020396 Bucharest, Romania
| |
Collapse
|
28
|
Schulz T, Marotz J, Seider S, Langer S, Leuschner S, Siemers F. Burn depth assessment using hyperspectral imaging in a prospective single center study. Burns 2022; 48:1112-1119. [PMID: 34702635 DOI: 10.1016/j.burns.2021.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/10/2021] [Accepted: 09/14/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND The assessment of thermal burn depth remains challenging. Over the last decades, several optical systems were developed to determine burn depth. So far, only laser doppler imaging (LDI) has been shown to be reliable while others such as infrared thermography or spectrophotometric intracutaneous analysis have been less accurate. The aim of our study is to evaluate hyperspectral imaging (HSI) as a new optical device. METHODS Patients suffering thermal trauma treated in a burn unit in Germany between November 2019 and September 2020 were included. Inclusion criteria were age ≥18 years, 2nd or 3rd degree thermal burns, written informed consent and presentation within 24 h after injury. Clinical assessment and hyperspectral imaging were performed 24, 48 and 72 h after the injury. Patients in whom secondary wound closure was complete within 21 days (group A) were compared to patients in whom secondary wound closure took more than 21 days or where skin grafting was indicated (group B). Demographic data and the primary parameters generated by HSI were documented. A Mann Whitney-U test was performed to compare the groups. A p-value below 0.05 was considered to be statistically significant. The data generated using HSI were combined to create the HSI burn index (BI). Using a logistic regression and receiver operating characteristics curve (ROC) sensitivity and specificity of the BI were calculated. The trial was officially registered on DRKS (registration number: DRKS00022843). RESULTS Overall, 59 patients with burn wounds were eligible for inclusion. Ten patients were excluded because of a poor data quality. Group A comprised 36 patients with a mean age of 41.5 years and a mean burnt body surface area of 2.7%. In comparison, 13 patients were allocated to group B because of the need for a skin graft (n = 10) or protracted secondary wound closure lasting more than 21 days. The mean age of these patients was 46.8 years. They had a mean affected body surface area of 4.0%. 24, 48, and 72 h after trauma the BI was 1.0 ± 0.28, 1.2 ± 0.29 and 1.55 ± 0.27 in group A and 0.78 ± 0.14, 1.05 ± 0.23 and 1.23 ± 0.27 in group B. At every time point significant differences were demonstrated between the groups. At 24 h, ROC analysis demonstrated BI threshold of 0.95 (sensitivity 0.61/specificity 1.0), on the second day of 1.17 (sensitivity 0.51/specificity 0.81) and on the third day of 1.27 (sensitivity 0.92/specificity 0.71). CONCLUSION Changes in microcirculation within the first 72 h after thermal trauma were reflected by an increasing BI in both groups. After 72 h, the BI is able to predict the need for a skin graft with a sensitivity of 92% and a specificity of 71%.
Collapse
Affiliation(s)
- Torsten Schulz
- Department of Orthopedic, Trauma and Plastic Surgery, Leipzig University Hospital, Germany.
| | - Jörg Marotz
- Department for Plastic- and Reconstructive Surgery, Burns Unit, BG Kliniken Bergmannstrost, Merseburger Straße 165, D-06120 Halle (Saale), Germany
| | - Sebastian Seider
- Medical Faculty of the Martin-Luther-Universität Halle-Wittenberg, Universitätsplatz 10, D-06108 Halle (Saale), Germany
| | - Stefan Langer
- Department for Orthopedics, Trauma- and Plastic Surgery-University Hospital Leipzig, Liebigstraße 20, D-04103 Leipzig, Germany
| | - Sebastian Leuschner
- Department for Plastic- and Reconstructive Surgery, Burns Unit, BG Kliniken Bergmannstrost, Merseburger Straße 165, D-06120 Halle (Saale), Germany
| | - Frank Siemers
- Department for Plastic- and Reconstructive Surgery, Burns Unit, BG Kliniken Bergmannstrost, Merseburger Straße 165, D-06120 Halle (Saale), Germany
| |
Collapse
|
29
|
Kiyota N, Shiga Y, Omodaka K, Nakazawa T. The relationship between choroidal blood flow and glaucoma progression in a Japanese study population. Jpn J Ophthalmol 2022; 66:425-433. [PMID: 35788445 DOI: 10.1007/s10384-022-00929-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 05/26/2022] [Indexed: 11/26/2022]
Abstract
PURPOSE To determine whether choroidal blood flow (BF) is related to visual field (VF) defect severity and progression in eyes with open-angle glaucoma (OAG). STUDY DESIGN Retrospective and longitudinal. METHODS This study comprised 443 eyes of 285 OAG patients who underwent laser speckle flowgraphy (LSFG), optical coherence tomography, and visual-field (VF) testing at baseline. The patients were then observed for at least 2 years and at least 5 reliable VF tests were performed. In the LSFG images, we set regions of interest at the optic nerve head (ONH) and the parapapillary choroid to obtain ONH-tissue mean blur rate (MBR) and choroidal MBR, respectively. We used univariable and multivariable linear mixed-effects models to determine clinical factors associated with choroidal MBR at baseline. We also used a linear mixed-effects model to determine the contribution of ONH-tissue MBR and choroidal MBR to baseline mean deviation (MD) and to MD slope during follow-up, adjusting for potential confounding factors, including circumpapillary retinal nerve fiber layer thickness. RESULTS Choroidal MBR was associated with age, MD slope, and ONH-tissue MBR (β = -0.181, P = 0.001; β = 0.134, P = 0.002; β = 0.096, P = 0.049, respectively). ONH-tissue MBR was associated with both MD and MD slope (β = 0.146, P = 0.004; β = 0.152, P = 0.009, respectively), whereas choroidal MBR was associated only with MD slope (β = 0.147, P = 0.005). CONCLUSION LSFG-derived choroidal MBR might be a useful biomarker to predict VF defect progression in a Japanese population.
Collapse
Affiliation(s)
- Naoki Kiyota
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, SendaiSendai, Miyagi, 980-8574, Japan
| | - Yukihiro Shiga
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, SendaiSendai, Miyagi, 980-8574, Japan
| | - Kazuko Omodaka
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, SendaiSendai, Miyagi, 980-8574, Japan
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, SendaiSendai, Miyagi, 980-8574, Japan.
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi, Japan.
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Miyagi, Japan.
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan.
| |
Collapse
|
30
|
Rozo A, Miskovic V, Rose T, Keersebilck E, Iorio C, Varon C. U-Net based Mapping from Digital Images to Laser Doppler Imaging for Burn Assessment. Annu Int Conf IEEE Eng Med Biol Soc 2022; 2022:459-462. [PMID: 36086430 DOI: 10.1109/embc48229.2022.9871759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The incidence of burn injuries is higher in low-and middle-income countries, and particularly in remote areas where the access to specialized burn assessment, care and recovery is limited. Given the high costs associated with one of the most used techniques to evaluate the severity of a burn, namely laser Doppler imaging (LDI), an alternative approach could be beneficial for remote locations. This study proposes a novel approach to estimate the LDI from digital images of a burn. The approach is a pixel-wise regression model based on convolutional neural networks. To minimize the dependency on the conditions in which the images are taken, the effect of two image normalization techniques is also studied. Results indicate that the model performs satisfactorily on average, presenting low mean absolute and squared errors and high structural similarity index. While no significant differences are found when changing the normalization of the images, the performance is affected by their quality. This suggests that changes in the intensity of the images do not alter the relevant information about the wound, whereas changes in brightness, contrast and sharpness do.
Collapse
|
31
|
Haneda M, Hashimoto Y, Mishima A, Saito D, Yoshitomi T. Changes in choroidal circulation hemodynamics during the menstrual cycle in young, healthy women. PLoS One 2022; 17:e0270501. [PMID: 35759478 PMCID: PMC9236247 DOI: 10.1371/journal.pone.0270501] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 06/10/2022] [Indexed: 11/19/2022] Open
Abstract
Purpose The current study aimed to investigate the time course of changes in choroidal circulation hemodynamics and their relationship to systemic circulation dynamics during the normal menstrual cycle in young, healthy women using laser speckle flowgraphy (LSFG). Methods This prospective study included 26 eyes from 13 young, healthy women (21.3 ± 4.0 years) with a normal menstrual cycle and 24 eyes from 12 young, healthy men (21.8 ± 4.4 years) as a control group. The macular mean blur rate (MBR), a quantitative index of relative blood flow velocity in the choroid, was measured using LSFG. MBR, intraocular pressure (IOP), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and ocular perfusion pressure (OPP) were evaluated in the late follicular phase and mid-luteal phase in women and at baseline and 10 days after baseline in men, respectively. Results In the female group, IOP, SBP, DBP, MBP, and OPP values were significantly higher in the mid-luteal phase than those observed in the late follicular phase (P = 0.035, P < 0.001, P = 0.041, P = 0.001, P = 0.014, respectively). The average macular MBR values in the late follicular phase and mid-luteal phase were 12.7 ± 5.3 and 13.7 ± 6.6 (+7.7 ± 19.4%), representing a significant increase in the mid-luteal phase (P = 0.041). The rate of change in MBR exhibited a significant positive correlation with changes in DBP and MBP (R = 0.456, P = 0.019 and R = 0.474, P = 0.014). However, there were no significant changes in any of the factors in the male group during the study period. Conclusions Our results suggest that in young, healthy women with a normal menstrual cycle, choroidal blood flow velocity decreases during the late follicular phase and increases during the mid-luteal phase, depending on systemic circulatory dynamics.
Collapse
Affiliation(s)
- Mayumi Haneda
- Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, Japan
| | - Yuki Hashimoto
- Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, Japan
- * E-mail:
| | - Airi Mishima
- Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, Japan
| | - Daichi Saito
- Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, Japan
| | - Takeshi Yoshitomi
- Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, Japan
| |
Collapse
|
32
|
Nam AS, Braaf B, Vakoc BJ. Using the dynamic forward scattering signal for optical coherence tomography based blood flow quantification. Opt Lett 2022; 47:3083-3086. [PMID: 35709056 PMCID: PMC9580005 DOI: 10.1364/ol.455475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
To our knowledge, all existing optical coherence tomography approaches for quantifying blood flow, whether Doppler-based or decorrelation-based, analyze light that is back-scattered by moving red blood cells (RBCs). This work investigates the potential advantages of basing these measurements on light that is forward-scattered by RBCs, i.e., by looking at the signals back-scattered from below the vessel. We show experimentally that flowmetry based on forward-scattering is insensitive to vessel orientation for vessels that are approximately orthogonal to the imaging beam. We further provide proof-of-principle demonstrations of dynamic forward-scattering (DFS) flowmetry in human retinal and choroidal vessels.
Collapse
Affiliation(s)
- Ahhyun Stephanie Nam
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom St, Boston, MA 02114 USA
- Harvard Medical School, 25 Shattuck St, Boston, MA 02115 USA
| | - Boy Braaf
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom St, Boston, MA 02114 USA
- Harvard Medical School, 25 Shattuck St, Boston, MA 02115 USA
| | - Benjamin J. Vakoc
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom St, Boston, MA 02114 USA
- Harvard Medical School, 25 Shattuck St, Boston, MA 02115 USA
| |
Collapse
|
33
|
Liu YJ, Wu P, An G, Fang Q, Zheng J, Wang YB. [Research advances on the techniques for diagnosing burn wound depth]. Zhonghua Shao Shang Yu Chuang Mian Xiu Fu Za Zhi 2022; 38:481-485. [PMID: 35599424 DOI: 10.3760/cma.j.cn501120-20210518-00195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The accurate diagnosis of burn wound depth is particularly important for evaluating the disease prognosis of burn patients. In the past, the diagnosis of burn wound depth often relied on the subjective judgment of doctors. With the continuous development of diagnostic technology, the methods for judging the depth of burn wound have also been updated. This paper mainly summarizes the research progress in the applications of indocyanine green angiography, laser Doppler imaging, laser speckle contrast imaging, and artificial intelligence in the diagnosis of burn wound depth, and compares the advantages and disadvantages of these techniques, so as to provide ideas for accurate diagnosis of burn wound depth.
Collapse
Affiliation(s)
- Y J Liu
- The First Clinical Medical College,Shandong University of Traditional Chinese Medicine, Jinan 250061, China
| | - P Wu
- Department of Plastic Surgery, the First Affiliated Hospital (Shandong Provincial Qianfoshan Hospital), Shandong First Medical University, Jinan Clinical Medicine Research Center for Tissue Engineering Skin Regeneration and Wound Repair, Jinan 250014, China
| | - G An
- Department of Plastic Surgery, the First Affiliated Hospital (Shandong Provincial Qianfoshan Hospital), Shandong First Medical University, Jinan Clinical Medicine Research Center for Tissue Engineering Skin Regeneration and Wound Repair, Jinan 250014, China
| | - Q Fang
- The First Clinical Medical College,Shandong University of Traditional Chinese Medicine, Jinan 250061, China
| | - J Zheng
- The First Clinical Medical College,Shandong University of Traditional Chinese Medicine, Jinan 250061, China
| | - Y B Wang
- Department of Plastic Surgery, the First Affiliated Hospital (Shandong Provincial Qianfoshan Hospital), Shandong First Medical University, Jinan Clinical Medicine Research Center for Tissue Engineering Skin Regeneration and Wound Repair, Jinan 250014, China
| |
Collapse
|
34
|
Liu C, Kobayashi T, Shiba T, Hayashi N. Effects of aging and exercise habits on blood flow profile of the ocular circulation. PLoS One 2022; 17:e0266684. [PMID: 35421147 PMCID: PMC9009706 DOI: 10.1371/journal.pone.0266684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 03/24/2022] [Indexed: 11/28/2022] Open
Abstract
Purpose We examined the effects of aging and exercise habits on the ocular blood flow (OBF) and its profiles throughout the optic nerve head region and choroidal area. We hypothesized that exercise habits reduce the stiffness of vessels in the ocular circulation, which generally increases with aging. Methods Participants in a medical checkup program (698 males and 192 females aged 28 to 80 years) were categorized into 2 groups (with and without exercise habits) based on participant self-reporting and the definition of the Ministry of Health, Labor and Welfare of Japan (MHLW). OBF in the right eye was measured and analyzed using laser speckle flowgraphy. The blowout time (BOT), which is the time during which the blood flow is higher than half of the mean of the minimum and maximum signals during one heartbeat, was calculated as an index of the blood flow profile. BOT has been used as an indicator of the flexibility of blood vessels. Results BOT significantly decreased with aging. Neither the self-reported nor MHLW-based exercise habits significantly affected the ocular circulation. Conclusion These results indicate that the stiffness of the ocular vessels increases with aging, and this cannot be prevented by exercise habits.
Collapse
Affiliation(s)
- Chihyun Liu
- School of Environment and Society, Department of Social and Human Sciences, Tokyo Institute of Technology, Tokyo, Japan
| | - Tatsuhiko Kobayashi
- Department of Ophthalmology, School of Medicine Toho University, Tokyo, Japan
| | - Tomoaki Shiba
- Department of Ophthalmology, International University of Health and Welfare, Narita Hospital, Chiba, Japan
| | - Naoyuki Hayashi
- School of Environment and Society, Department of Social and Human Sciences, Tokyo Institute of Technology, Tokyo, Japan
- Faculty of Sport Sciences, Waseda University, Saitama, Japan
- * E-mail:
| |
Collapse
|
35
|
De Becker B, Hupkens E, Dewachter L, Coremans C, Delporte C, van Antwerpen P, Franck T, Zouaoui Boudjeltia K, Cullus P, van de Borne P. Acute effects of hypouricemia on endothelium, oxidative stress, and arterial stiffness: A randomized, double-blind, crossover study. Physiol Rep 2021; 9:e15018. [PMID: 34435469 PMCID: PMC8387791 DOI: 10.14814/phy2.15018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/06/2021] [Accepted: 08/07/2021] [Indexed: 01/07/2023] Open
Abstract
We hypothesized acute moderate and drastic reductions in uric acid concentration exert different effects on arterial function in healthy normotensive and hypertensive adults. Thirty-six adults (aged 58 [55;63] years) with or without primary hypertension participated in a three-way, randomized, double-blind, crossover study in which [placebo] and [febuxostat] and [febuxostat and rasburicase] were administered. Febuxostat and rasburicase reduce the uric acid concentration by xanthine oxidoreductase inhibition and uric acid degradation into allantoin, respectively. Endothelial function was assessed in response to acetylcholine, sodium nitroprusside, heating (with and without nitric oxide synthase inhibition) using a laser Doppler imager. Arterial stiffness was determined by applanation tonometry, together with blood pressure, renin-angiotensin system activity, oxidative stress, and inflammation. Uric acid concentration was 5.1 [4.1;5.9], 1.9 [1.2;2.2] and 0.2 [0.2;0.3] mg/dL with [placebo], [febuxostat] and [febuxostat-rasburicase] treatments, respectively (p < 0.0001). Febuxostat improved endothelial response to heat particularly when nitric oxide synthase was inhibited (p < 0.05) and reduced diastolic and mean arterial pressure (p = 0.008 and 0.02, respectively). The augmentation index decreased with febuxostat (ANOVA p < 0.04). Myeloperoxidase activity profoundly decreased with febuxostat combined with rasburicase (p < 0.0001). When uric acid dropped, plasmatic antioxidant capacity markedly decreased, while superoxide dismutase activity increased (p < 0.0001). Other inflammatory and oxidant markers did not differ. Acute moderate hypouricemia encompasses minor improvements in endothelial function, blood pressure, and arterial stiffness. Clinical Trial Registration: NCT03395977, https://clinicaltrials.gov/ct2/show/NCT03395977.
Collapse
Affiliation(s)
- Benjamin De Becker
- Department of CardiologyErasme HospitalUniversité Libre de BruxellesBrusselsBelgium
| | - Emeline Hupkens
- Laboratory of Physiology and PharmacologyFaculty of MedicineUniversité Libre de BruxellesBrusselsBelgium
| | - Laurence Dewachter
- Laboratory of Physiology and PharmacologyFaculty of MedicineUniversité Libre de BruxellesBrusselsBelgium
| | - Catherine Coremans
- RD3 – Pharmacognosy, Bioanalysis and Drug Discovery & Analytical Platform of the Faculty of Pharmacy (APFP)Faculty of PharmacyUniversité Libre de BruxellesBrusselsBelgium
| | - Cédric Delporte
- RD3 – Pharmacognosy, Bioanalysis and Drug Discovery & Analytical Platform of the Faculty of Pharmacy (APFP)Faculty of PharmacyUniversité Libre de BruxellesBrusselsBelgium
| | - Pierre van Antwerpen
- RD3 – Pharmacognosy, Bioanalysis and Drug Discovery & Analytical Platform of the Faculty of Pharmacy (APFP)Faculty of PharmacyUniversité Libre de BruxellesBrusselsBelgium
| | - Thierry Franck
- Centre of Oxygen, Research and DevelopmentInstitute of Chemistry B 6aUniversity of Liege ‐ Sart TilmanLiègeBelgium
| | - Karim Zouaoui Boudjeltia
- Laboratory of Experimental Medicine (ULB 222)Medicine FacultyUniversité Libre de BruxellesCHU de Charleroi, Hopital VesaleMontigny‐le‐TilleulBelgium
| | - Pierre Cullus
- Biostatistics department, Medicine FacultyUniversité Libre de BruxellesBrusselsBelgium
| | | |
Collapse
|
36
|
Yuan Y, Bi Y, Gao XC, Sun MY, Gao WN. High-dynamic-range blood flow rate measurement in a large-diameter vessel. Appl Opt 2021; 60:6837-6842. [PMID: 34613163 DOI: 10.1364/ao.432846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
We propose a new, to the best of our knowledge, compound technique to measure high-dynamic-range blood flow rate in a large-diameter vessel, which combines the dynamic scattering light (DLS) and the laser speckle contrast imaging (LSCI) methods, possessing the advantages of the high temporal resolution of DLS and the robust property of LSCI. By controlling the second-order spatial correlations of the laser speckle through two imaging systems, the speckle temporal intensity autocorrelation function g2(t) and the decorrelation time τc are directly measured using a high-speed camera. It turns out the enhanced spatial second-order correlation helps to measure the blood flow with higher dynamic range and that the measured parameter β and the blood flow dynamics n were accurately determined. For further improvement the dynamic range, the modified LSCI method was adopted, and the decorrelation time as a function of blood flow rate was constructed. It reveals the feasibility of measuring the high flow rate in large-diameter vessels and provides significant guidance for the future biomedical study of the myocardial perfusion in coronary artery bypass grafting, ghost imaging, and ghost cytometry.
Collapse
|
37
|
Hong J, Zhu X, Lu J, Li P. Quantitative laser speckle auto-inverse covariance imaging for robust estimation of blood flow. Opt Lett 2021; 46:2505-2508. [PMID: 33988621 DOI: 10.1364/ol.422062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
We present a quantitative model to provide robust estimation of the decorrelation time using laser speckle auto-inverse covariance. It has the advantages of independence from the statistical sample size, speckle size, static scattering, and detector noise. We have shown cerebral blood flow imaging through an intact mouse skull using this model. Phantom experiments and two animal models, middle cerebral artery occlusion, and cortical spreading depression were used to evaluate its performance.
Collapse
|
38
|
Busch DR, Lin W, Goh CC, Gao F, Larson N, Wahl J, Bilfinger TV, Yodh AG, Floyd TF. Towards rapid intraoperative axial localization of spinal cord ischemia with epidural diffuse correlation monitoring. PLoS One 2021; 16:e0251271. [PMID: 33970932 PMCID: PMC8109798 DOI: 10.1371/journal.pone.0251271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 04/23/2021] [Indexed: 11/19/2022] Open
Abstract
Spinal cord ischemia leads to iatrogenic injury in multiple surgical fields, and the ability to immediately identify onset and anatomic origin of ischemia is critical to its management. Current clinical monitoring, however, does not directly measure spinal cord blood flow, resulting in poor sensitivity/specificity, delayed alerts, and delayed intervention. We have developed an epidural device employing diffuse correlation spectroscopy (DCS) to monitor spinal cord ischemia continuously at multiple positions. We investigate the ability of this device to localize spinal cord ischemia in a porcine model and validate DCS versus Laser Doppler Flowmetry (LDF). Specifically, we demonstrate continuous (>0.1Hz) spatially resolved (3 locations) monitoring of spinal cord blood flow in a purely ischemic model with an epidural DCS probe. Changes in blood flow measured by DCS and LDF were highly correlated (r = 0.83). Spinal cord blood flow measured by DCS caudal to aortic occlusion decreased 62%. This monitor demonstrated a sensitivity of 0.87 and specificity of 0.91 for detection of a 25% decrease in flow. This technology may enable early identification and critically important localization of spinal cord ischemia.
Collapse
Affiliation(s)
- David R. Busch
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Neurology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Wei Lin
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Chia Chieh Goh
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Feng Gao
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Nicholas Larson
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Joseph Wahl
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Thomas V. Bilfinger
- Department of Surgery, Stony Brook University, Stony Brook, New York, United States of America
| | - Arjun G. Yodh
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Thomas F. Floyd
- Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Cardiothoracic Surgery, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail:
| |
Collapse
|
39
|
Shirazi BR, Valentine RJ, Lang JA. Reproducibility and normalization of reactive hyperemia using laser speckle contrast imaging. PLoS One 2021; 16:e0244795. [PMID: 33412561 PMCID: PMC7790538 DOI: 10.1371/journal.pone.0244795] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 12/16/2020] [Indexed: 12/27/2022] Open
Abstract
Background Impaired perfusion indices signal potential microvascular dysfunction preceding atherosclerosis and other cardiometabolic pathologies. Post-occlusive reactive hyperemia (PORH), a vasodilatory response following a mechanically induced ischemia, is a transient increase in perfusion and can assess microvascular function. The greatest blood flow change corresponding to the first minute of hyperemia (represented by time-to-peak, hyperemic velocity, AUC within 1st min) has been shown to indicate microvascular dysfunction. However, the reproducibility of these temporal kinetic indices of the PORH response is unknown. Our aim was to examine the inter- and intra-day reproducibility and standardization of reactive hyperemia, with emphasis on the kinetic indices of PORH, using laser speckle contrast imaging (LSCI) technique. Methods and results Seventeen healthy adults (age = 24 ± 3 years) completed three PORH bouts over two lab visits. LSCI region of interest was a standardized 10 cm region on the dominant ventral forearm. A 5-min brachial artery occlusion period induced by inflating an arm cuff to 200 mmHg, preceded a 4-min hyperemic period. Inter- and intra-day reliability and reproducibility of cutaneous vascular conductance (LSCI flux / mean arterial pressure) were determined using intraclass correlation (ICC) and coefficient of variation (CV%). Maximal flow and area under the curve standardized to zero perfusion showed intra- and inter-day reliability (ICC > 0.70). Time to maximal flow (TMF) was not reproducible (inter-day CV = 18%). However, alternative kinetic indices such as 1-min AUC and overshoot rate-of-change (ORC), represented as a piecewise function (at 5s, 10s, 15s, and 20s into hyperemia), were reproducible (CV< 11%). Biological zero was a reliable normalization point. Conclusion PORH measured with LSCI is a reliable assessment of microvascular function. However, TMF or its derived hyperemic velocity are not recommended for longitudinal assessment. Piecewise ORC and 1-min AUC are reliable alternatives to assess the kinetic response of PORH.
Collapse
Affiliation(s)
| | - Rudy J. Valentine
- Department of Kinesiology, Iowa State University, Ames, Iowa, United States of America
| | - James A. Lang
- Department of Kinesiology, Iowa State University, Ames, Iowa, United States of America
- * E-mail:
| |
Collapse
|
40
|
Palnitkar H, Henry BM, Dai Z, Peng Y, Mansy HA, Sandler RH, Balk RA, Royston TJ. Sound transmission in human thorax through airway insonification: an experimental and computational study with diagnostic applications. Med Biol Eng Comput 2020; 58:2239-2258. [PMID: 32666412 PMCID: PMC7501255 DOI: 10.1007/s11517-020-02211-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 06/25/2020] [Indexed: 12/01/2022]
Abstract
Pulmonary diseases and injury lead to structural and functional changes in the lung parenchyma and airways, often resulting in measurable sound transmission changes on the chest wall surface. Additionally, noninvasive imaging of externally driven mechanical wave motion in the chest (e.g., using magnetic resonance elastography) can provide information about lung stiffness and other structural property changes which may be of diagnostic value. In the present study, a comprehensive computational simulation (in silico) model was developed to simulate sound wave propagation in the airways, parenchyma, and chest wall under normal and pathological conditions that create distributed structural (e.g., pneumothoraces) and diffuse material (e.g., fibrosis) changes, as well as a localized structural and material changes as may be seen with a neoplasm. Experiments were carried out in normal subjects to validate the baseline model. Sound waves with frequency content from 50 to 600 Hz were introduced into the airways of three healthy human subjects through the mouth, and transthoracic transmitted waves were measured by scanning laser Doppler vibrometry at the chest wall surface. The computational model predictions of a frequency-dependent decreased sound transmission due to pneumothorax were consistent with experimental measurements reported in previous work. Predictions for the case of fibrosis show that while shear wave motion is altered, changes to compression wave propagation are negligible, and thus, insonification, which primarily drives compression waves, is not ideal to detect the presence of fibrosis. Results from the numerical simulation of a tumor show an increase in the wavelength of propagating waves in the immediate vicinity of the tumor region. Graphical abstract.
Collapse
Affiliation(s)
- Harish Palnitkar
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 842 W. Taylor St, Chicago, IL, 60607, USA.
| | - Brian M Henry
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Zoujun Dai
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Ying Peng
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 842 W. Taylor St, Chicago, IL, 60607, USA
| | | | | | - Robert A Balk
- Rush University Medical Center, Chicago, IL, 60612, USA
| | - Thomas J Royston
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 842 W. Taylor St, Chicago, IL, 60607, USA
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| |
Collapse
|
41
|
Loutfi H, Pellen F, Jeune BL, Lteif R, Kallassy M, Brun GL, Abboud M. Interpretation of the bacterial growth process based on the analysis of the speckle field generated by calibrated scattering media. Opt Express 2020; 28:28648-28655. [PMID: 32988131 DOI: 10.1364/oe.400909] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 07/24/2020] [Indexed: 06/11/2023]
Abstract
The speckle imaging technique has been proven to be a reliable and effective method for real-time monitoring of the growth kinetics of any bacterium in suspension. To understand the interaction between the light and the bacterial density, a simulation of the bacterial growth of Bacillus thuringiensis was performed using calibrated microspheres of different concentrations and sizes. Results show that the decrease of speckle grain size with the increase of the medium scattering coefficient reveals the two essential phases of the bacterial growth: the exponential phase where the number of the bacteria increases and the stationary phase where sporulation and cell lysis occur.
Collapse
|
42
|
Hartlief GA, Niemeijer AS, Lamberts KF, Nieuwenhuis MK. The impact of early information concerning the surgical operations on anxiety in patients with burns. Burns 2020; 47:847-853. [PMID: 32978010 DOI: 10.1016/j.burns.2020.08.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 07/10/2020] [Accepted: 08/28/2020] [Indexed: 11/18/2022]
Abstract
AIMS Stress has been linked to poor coping with health-related issues, poor adaptation, a decrease of quality of life, poor recovery and poor wound healing. Therefore, it is important to address patients' uncertainty and feelings of anxiety. The aim of this study was to examine the effect of providing early treatment information based on an LDI-scan to patients with burns on their feelings of anxiety. DESIGN An observational prospective pre-test post-test study. METHODS Patients with intermediate burns (n = 59) admitted to our burn centre in 2016 were evaluated for anxiety using a visual analogue scale (VAS-A) before and after an LDI-scan was made. Two groups were compared: a group that heard whether surgery would or would not be recommended for wound closure (certain group) versus a group that heard to wait and see whether an operation was determined to be helpful (uncertain group). RESULTS Before the LDI-scan was made, both groups showed clinically high levels of anxiety (median VAS scores above 5). After the information gathered with the LDI was discussed with the patient, anxiety dropped significantly (median VAS below 3; p = .001). No significant differences between the groups were observed (p > .05). CONCLUSION In contrast to other studies, anxiety was significantly reduced in all our study groups after information was shared. Early communication of knowledge by health care professionals is important regardless whether it includes treatment uncertainty.
Collapse
Affiliation(s)
- Gera A Hartlief
- Martini Hospital, Burn Centre, P.O. Box 30.033, 9700 RM Groningen, The Netherlands.
| | - Anuschka S Niemeijer
- Martini Hospital, Burn Centre, P.O. Box 30.033, 9700 RM Groningen, The Netherlands; Association of Dutch Burn Centres, Martini Hospital, Burn Centre, P.O. Box 30.033, 9700 RM Groningen, The Netherlands; Martini Hospital, Scientific Institute, P.O. Box 30.033, 9700 RM Groningen, The Netherlands
| | - Kirsten F Lamberts
- Martini Hospital, Burn Centre, P.O. Box 30.033, 9700 RM Groningen, The Netherlands
| | - Marianne K Nieuwenhuis
- Martini Hospital, Burn Centre, P.O. Box 30.033, 9700 RM Groningen, The Netherlands; Association of Dutch Burn Centres, Martini Hospital, Burn Centre, P.O. Box 30.033, 9700 RM Groningen, The Netherlands
| |
Collapse
|
43
|
Zhu T, Wang Y, Wang X, Liao F, Liu Y, Jan YK. Effect of Local Vibrations on Plantar Skin Blood Flow Responses During Weight-bearing Standing in Healthy Volunteers. Wound Manag Prev 2020; 66:7-14. [PMID: 32732438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
UNLABELLED Plantar foot pressure is a risk factor for the development of foot ulcers in persons with diabetes mellitus. PURPOSE The objective of this study was to examine the effects of local vibrations on plantar skin blood flow (SBF) responses during weight-bearing standing. Wavelet analysis of plantar SBF was used to analyze microvascular regulation in response to standing with and without local vibrations. METHODS Fifteen (15) healthy participants (26.5 ± 5.7 years; 4 male and 11 female) received a local vibration intervention (35 Hz, 1 mm, 2 g vibration) and a sham vibration to the skin of the right first metatarsal head during 10-minute standing. Laser Doppler flowmetry was used to measure SBF before and after 10 minutes of standing. SBF after standing was expressed as a ratio of SBF before standing to minimize blood flow variations. The use of wavelet analysis allowed the authors to examine the frequency bands corresponding to the physiological controls in the vibration and sham areas of the foot, including metabolic (0.0095-0.02 Hz), neurogenic (0.02-0.05 Hz), myogenic (0.05-0.15 Hz), respiratory (0.15-0.4 Hz), and cardiac (0.4-2.0 Hz) regulations. RESULTS Plantar SBF ratio changes in the vibration protocol (1.83 ± 0.27) were significantly higher compared with the sham protocol (0.97 ± 0.08) (P < .01). SBF before and after the 35 Hz vibrations were 41.96 ± 14.02 perfusion units (range 6.68-208.9 perfusion units) and 61.16 ± 14.74 perfusion units (range 7.76-155.37 perfusion units), respectively. SBF before and after the sham vibration were 37.32 ± 9.29 perfusion units (range 5.74-120.44 perfusion units) and 33.97 ± 8.11 perfusion units (range 6.95-108.44 perfusion units), respectively. Wavelet analysis of SBF oscillations showed a significant difference in all regulations: metabolic (P < .05), neurogenic (P < .05), myogenic (P < .05), respiratory (P < .05), and cardiac (P < .05) in response to 35 Hz local vibrations compared with the sham vibration. CONCLUSIONS Local vibrations (35 Hz frequency, 1 mm amplitude) to the plantar tissues during 10 minutes of weight-bearing standing resulted in a significant increase in after-standing plantar SBF compared with sham vibration. The control mechanisms contributing to this increase in SBF were metabolic, neurogenic, myogenic, respiratory, and cardiac regulations. These findings confirm results of preclinical studies and support the need for additional research to examine the potential protective effects of local vibration to decrease the risk of plantar ulcers.
Collapse
Affiliation(s)
- Ting Zhu
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Champaign, Illinois
| | - Yana Wang
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Champaign, Illinois; Shanghai First Rehabilitation Hospital, Shanghai, China
| | - Xiaoling Wang
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Champaign, Illinois
| | - Fuyuan Liao
- Department of Biomedical Engineering, Xi'an Technological University, Xi'an, China
| | - Yu Liu
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Yih-Kuen Jan
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Champaign, Illinois
| |
Collapse
|
44
|
Sawada S, Tsuchiya S, Kodama S, Kurosawa S, Endo A, Sugawara H, Hosaka S, Kawana Y, Asai Y, Yamamoto J, Munakata Y, Izumi T, Takahashi K, Kaneko K, Imai J, Ito A, Yasuda M, Kunikata H, Nakazawa T, Katagiri H. Vascular resistance of carotid and vertebral arteries is associated with retinal microcirculation measured by laser speckle flowgraphy in patients with type 2 diabetes mellitus. Diabetes Res Clin Pract 2020; 165:108240. [PMID: 32502691 DOI: 10.1016/j.diabres.2020.108240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/01/2020] [Accepted: 05/21/2020] [Indexed: 01/31/2023]
Abstract
AIMS Evaluation of the retinal microcirculation is key to understanding retinal vasculopathies, such as diabetic retinopathy. Laser speckle flowgraphy (LSFG) has recently enabled us to directly evaluate the vascular resistance in both retinal vessels and capillaries, non-invasively. We therefore assessed whether retinal vessel blood flow and/or the capillary microcirculation are associated with blood flow in the cervical arteries in diabetic patients without severe retinopathy. METHODS We enrolled 110 type 2 diabetes patients, with no or mild non-proliferative diabetic retinopathy, in this prospective cross-sectional study. We measured the resistivity indices (RIs) of the retinal vessel and capillaries by LSFG and those of cervical arteries by Doppler ultrasonography, followed by analyzing associations. RESULTS The RIs of not only the carotid but also vertebral arteries were associated with those of retinal vessel blood flow and the retinal capillary microcirculation. Multiple regression analyses revealed these associations to be independent of other explanatory variables including age and diabetes duration. CONCLUSIONS We obtained novel and direct evidence demonstrating a close association between the retinal microcirculation and cervical artery hemodynamics in diabetic patients. These findings suggest shared mechanisms to underlie micro- and macro-angiopathies. Thus, high vascular resistance of cervical arteries may be a risk of developing retinopathy.
Collapse
Affiliation(s)
- Shojiro Sawada
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan.
| | - Satoko Tsuchiya
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Shinjiro Kodama
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Satoko Kurosawa
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Akira Endo
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroto Sugawara
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Shinichiro Hosaka
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yohei Kawana
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yoichiro Asai
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junpei Yamamoto
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yuichiro Munakata
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Tomohito Izumi
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kei Takahashi
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Keizo Kaneko
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Junta Imai
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Azusa Ito
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masayuki Yasuda
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroshi Kunikata
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hideki Katagiri
- Department of Metabolism and Diabetes, Tohoku University Graduate School of Medicine, Sendai, Japan.
| |
Collapse
|
45
|
Shatokhina SN, Filippov AG, Aleksandrin VV, Uvarova DS, Kubatiev AA, Shabalin VN. Effect of Platinum Nanoparticles on the Structure of Protein Molecules and Regulation of the Tone of Brain Vessels in Experimental Animals. Bull Exp Biol Med 2020; 168:781-784. [PMID: 32328947 DOI: 10.1007/s10517-020-04801-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Indexed: 11/26/2022]
Abstract
The effects of platinum nanoparticles on the morphological structures of the solid phase of blood serum and the tone of cerebral microvessels as indicators of the dynamics of homeostasis were studied on outbred albino male rats (n=40) weighing 300-350 g. Platinum nanoparticles were injected to experimental animals in 1 ml of physiological saline. For systemic BP measurements and blood sampling, the femoral artery was isolated and catheterized. The study of solid phase structures of blood serum was conducted by the method of cuneiform dehydration. The results showed that injection of platinum nanoparticles significantly affected the body of experimental animals.
Collapse
Affiliation(s)
- S N Shatokhina
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia.
| | - A G Filippov
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - V V Aleksandrin
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - D S Uvarova
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - A A Kubatiev
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - V N Shabalin
- Research Institute of General Pathology and Pathophysiology, Moscow, Russia
| |
Collapse
|
46
|
Mongkolpun W, Orbegozo D, Cordeiro CPR, Franco CJCS, Vincent JL, Creteur J. Alterations in Skin Blood Flow at the Fingertip Are Related to Mortality in Patients With Circulatory Shock. Crit Care Med 2020; 48:443-450. [PMID: 32205589 DOI: 10.1097/ccm.0000000000004177] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Skin blood flow is rapidly altered during circulatory shock and may remain altered despite apparent systemic hemodynamic stabilization. We evaluated whether changes in skin blood flow during circulatory shock were related to survival. DESIGN Prospective study. SETTING Thirty-five-bed medical-surgical university hospital department of intensive care. SUBJECTS Twenty healthy volunteers and 70 patients with circulatory shock (< 12 hr duration), defined as the need for vasopressors to maintain mean arterial pressure greater than or equal to 65 mm Hg and signs of altered tissue perfusion. INTERVENTIONS We assessed skin blood flow using skin laser Doppler on the fingertip for 3 minutes at basal temperature (SBFBT) and at 37°C (SBF37) (thermal challenge test) once in volunteers and at the time of inclusion and after 6, 24, 48, 72, and 96 hours in patients with shock. Capillary refill time and peripheral perfusion index were measured at the same time points on the contralateral hand. MEASUREMENTS AND MAIN RESULTS The thermal challenge response (ΔSBF/ΔT) was calculated using the following formula: (SBF37-SBFBT)/(37-basal temperature). Area under the receiver operating characteristic curves were calculated to evaluate variables predictive of ICU mortality. At inclusion, skin blood flow and ΔSBF/ΔT were lower in patients than in volunteers. Baseline skin blood flow (31 [17-113] vs 16 [9-32] arbitrary perfusion units; p = 0.01) and ΔSBF/ΔT (4.3 [1.7-10.9] vs 0.9 [0.4-2.9] arbitrary perfusion unit/s) were greater in survivors than in nonsurvivors. Capillary refill time was shorter in survivors than in nonsurvivors; peripheral perfusion index was similar in the two groups. ΔSBF/ΔT (area under the receiver operating characteristic curve 0.94 [0.88-0.99]) and SBFBT (area under the receiver operating characteristic curve 0.83 [0.73-0.93]) had the best predictive value for ICU mortality with cutoff values less than or equal to 1.25 arbitrary perfusion unit/°C (sensitivity 88%, specificity 89%) and less than or equal to 21 arbitrary perfusion unit (sensitivity 84%, specificity 81%), respectively. CONCLUSIONS Alterations in fingertip skin blood flow can be evaluated using a laser Doppler thermal challenge technique in patients with circulatory shock and are directly related to outcome. These novel monitoring techniques could potentially be used to guide resuscitation.
Collapse
Affiliation(s)
- Wasineenart Mongkolpun
- All authors: Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | | | | | | | | | | |
Collapse
|
47
|
Toto L, Evangelista F, Viggiano P, Erroi E, D'Onofrio G, Libertini D, Porreca A, D'Aloisio R, Mariacristina P, Di Antonio L, Di Nicola M, Mastropasqua R. Changes in Ocular Blood Flow after Ranibizumab Intravitreal Injection for Diabetic Macular Edema Measured Using Laser Speckle Flowgraphy. Biomed Res Int 2020; 2020:9496242. [PMID: 32104710 PMCID: PMC7035512 DOI: 10.1155/2020/9496242] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 11/17/2022]
Abstract
PURPOSE To evaluate the effects of intravitreal ranibizumab (IVR) treatment on the blood flow of the optic nerve head (ONH) and of retinal vessels of the peripapillary region of eyes with diabetic macular edema (DME) assessed using laser speckle flowgraphy (LSFG). METHODS Forty eyes of 30 patients treated with IVR for DME were included in this prospective clinical study. Mean blur rate (MBR) and relative flow volume (RFV) of the ONH and of a superior retinal artery and an inferior retinal vein of the peripapillary region were measured using LSFG at baseline, 2 weeks (T1), and 1 month (T2) after IVR injection. In addition, best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were measured in all cases. RESULTS The BCVA improved and CRT decreased significantly during the follow-up period (p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA, p < 0.010). MBR-related parameters of the ONH such as MBR of all area (MA), MBR of vascular area (MV), and MBR of tissue area (MT) decreased significantly at 2 weeks after IVR compared to baseline values (MA. CONCLUSION IVR injection leads to a reduction of ocular blood flow both in the ONH and in the retinal peripapillary vessels associated with peripapillary vessel constriction. The reduction of CRT and related improvement of vision may be related to the changes in ocular blood flow.
Collapse
Affiliation(s)
- Lisa Toto
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Federica Evangelista
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Pasquale Viggiano
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Emanuele Erroi
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Giada D'Onofrio
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Daniele Libertini
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Annamaria Porreca
- Department of Economic Studies, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Rossella D'Aloisio
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | | | - Luca Di Antonio
- Ophthalmology Clinic, Department of Medicine and Science of Ageing, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Italy
| | - Marta Di Nicola
- Department of Medical, Oral and Biotechnological Sciences, Laboratory of Biostatistics, University “G. d'Annunzio” Chieti-Pescara, Chieti 66100, Via dei Vestini 31, Italy
| | - Rodolfo Mastropasqua
- Institute of Ophthalmology, University of Modena and Reggio Emilia, Modena, Italy
| |
Collapse
|
48
|
Salmi A, Nieminen HJ, Veira Canle D, Hæggström E, Kontiola A. Non-contact determination of intra-ocular pressure in an ex vivo porcine model. PLoS One 2020; 15:e0227488. [PMID: 32012155 PMCID: PMC6996824 DOI: 10.1371/journal.pone.0227488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 12/19/2019] [Indexed: 11/19/2022] Open
Abstract
People suffering from glaucoma often endure high intra-ocular pressure (IOP). Methods for determining IOP either contact the eye or are unpleasant to some patients. There is therefore a need for a rapid and patient friendly non-contacting method to determine IOP. To address this need, we developed a tonometer prototype that employs spark-gap induced shock waves and a laser Doppler vibrometer (LDV) that reads the amplitude of membrane waves. The IOP was first identified from the membrane wave propagation velocity first in a custom-made ocular phantom and was then verified in ex vivo porcine eyes. The time-of-flight (TOF) of the membrane wave travelling on a hemispherical membrane was compared to reference IOP values in the sample obtained with an iCare TA01 tonometer. The shock front was characterized by high speed photography. Within one eye, the method achieved an agreement of 5 mmHg (1.96 standard deviation between the shock wave tonometer and the commercial manometer) and high method-to-method association (Pearson correlation, R2 = 0.98). The results indicate that the presented method could potentially be developed into a non-contacting technique for measuring IOP in vivo.
Collapse
Affiliation(s)
- Ari Salmi
- Division of Materials Physics, Department of Physics, University of Helsinki, Helsinki, Finland
- * E-mail:
| | - Heikki J. Nieminen
- Division of Materials Physics, Department of Physics, University of Helsinki, Helsinki, Finland
| | - Daniel Veira Canle
- Division of Materials Physics, Department of Physics, University of Helsinki, Helsinki, Finland
- Photono Oy, Helsinki, Finland
| | - Edward Hæggström
- Division of Materials Physics, Department of Physics, University of Helsinki, Helsinki, Finland
| | | |
Collapse
|
49
|
Konschake W, Lutze S, Haase H, Jünger M, Arnold A. Analysis of pigmented skin lesions and malignant melanoma by Laser Doppler flowmetry - Report of different cases and further analysis by a neuronal network. Clin Hemorheol Microcirc 2020; 76:525-533. [PMID: 32924991 DOI: 10.3233/ch-200876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Dermatoscopy is successfully used for the early diagnosis of suspicious skin lesions, however, correct diagnosis depends on training. There is evidence that wavelet analysis by Laser Doppler flowmetry (LDF) can identify malignant melanomas by their hypervascularization and changes in the capillary morphology. OBJECTIVE To show the capability of LDF in the distinction of melanomas and benign pigmented skin lesions based on data collected over 16 years. METHODS Evaluation of pigmented skin lesions was based on clinical information. The LDF measurements were taken. The suspect lesion was excised afterwards for histological work-up. Four case reports are presented. Data collected over 16 years was processed into a neuronal network to estimate the dignity of the lesion. RESULTS A total of 517 suspicious lesions were analyzed by LDF. In the histological work-up, 114 lesions turned out to be melanomas, whereas 403 benign naevi were secured. Specificity to detect melanomas was good based on the clinical information. The LDF increases the sensitivity of melanoma detection, which is also illustrated in four case reports. CONCLUSION In addition to clinical parameters, such as color and border, information from the LDF can help in the diagnosis of malignant melanomas. The LDF provides information on the vascularization of the skin lesion.
Collapse
Affiliation(s)
- Wolfgang Konschake
- Department of Dermatology, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Stine Lutze
- Department of Dermatology, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Hermann Haase
- Department of Dermatology, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Michael Jünger
- Department of Dermatology, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Andreas Arnold
- Department of Dermatology, Universitätsmedizin Greifswald, Greifswald, Germany
| |
Collapse
|
50
|
Perez-Corona CE, Peregrina-Barreto H, Ramirez-San-Juan JC. Space-directional approach to improve blood vessel visualization and temporal resolution in laser speckle contrast imaging. J Biomed Opt 2019; 25:1-16. [PMID: 31833281 PMCID: PMC7011032 DOI: 10.1117/1.jbo.25.3.032009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Blood flow is a parameter used to diagnose vascular diseases based on flow speed, blood pressure, and vessel size. Different techniques have been developed to estimate the relative blood flow speed and to improve the visualization of deep blood vessels; one such technique is laser speckle contrast imaging (LSCI). LSCI images contain a high level of noise mainly when deep blood vessels are imaged. To improve their visualization, several approaches for contrast computation have been developed. However, there is a compromise between noise attenuation and temporal resolution. On the one hand, spatial approaches have low spatial resolution, high temporal resolution, and significant noise attenuation, while temporal approaches have the opposite. A recent approach combines a temporal base with a directional process that allows improving the visualization of blood vessels. Nevertheless, it still contains a high level of noise and requires a high number of raw frames for its base. We propose, a space-directional approach focused on improving noise attenuation and temporal resolution for contrast computation. The results of reference approaches and the proposed one are compared quantitatively. Moreover, it is shown that the visualization of blood vessels in LSCI images can be improved by a general morphological process when the noise level is reduced.
Collapse
Affiliation(s)
- C. Elizabeth Perez-Corona
- Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Department of Optics, Puebla, Mexico
| | - Hayde Peregrina-Barreto
- Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Department of Computer Sciences, Puebla, Mexico
| | - Julio C. Ramirez-San-Juan
- Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Department of Optics, Puebla, Mexico
| |
Collapse
|