High Speed Digital Video Capillaroscopy: Nailfold Capillary Shape Analysis and Red Blood Cell Velocity Measurement

Watanabe, Masao; Matsubara, Masaharu; Sanada, Toshiyuki; Kuroda, Hiroaki; Iribe, Masaki; Furue, Masutaka

doi:10.1299/jbse.2.81

Cited by 8 publications

(6 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, the results are in arbitrary units and are not directly related to the actual flow values. Moreover, the conventional OC methods, including the frame difference method and the optical flow method, 13,14 can visualize some capillaries under the nailfold and skin, but their blood flow velocity measurements rely on computer video processing. Calculations in the frame difference method are simple and update quickly; however, this method is vulnerable to image noise, and the result heavily depends on the threshold selection in the algorithm.…”

Section: Introductionmentioning

confidence: 99%

In-vivo full-field measurement of microcirculatory blood flow velocity based on intelligent object identification

Ye¹,

Yin

et al. 2020

J. Biomed. Opt.

View full text Add to dashboard Cite

Microcirculation plays a crucial role in delivering oxygen and nutrients to living tissues and in removing metabolic wastes from the human body. Monitoring the velocity of blood flow in microcirculation is essential for assessing various diseases, such as diabetes, cancer, and critical illnesses. Because of the complex morphological pattern of the capillaries, both in-vivo capillary identification and blood flow velocity measurement by conventional optical capillaroscopy are challenging. Thus, we focused on developing an in-vivo optical microscope for capillary imaging, and we propose an in-vivo full-field flow velocity measurement method based on intelligent object identification. The proposed method realizes full-field blood flow velocity measurements in microcirculation by employing a deep neural network to automatically identify and distinguish capillaries from images. In addition, a spatiotemporal diagram analysis is used for flow velocity calculation. In-vivo experiments were conducted, and the images and videos of capillaries were collected for analysis. We demonstrated that the proposed method is highly accurate in performing full-field blood flow velocity measurements in microcirculation. Further, because this method is simple and inexpensive, it can be effectively employed in clinics. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

show abstract

Section: Introductionmentioning

confidence: 99%

In-vivo full-field measurement of microcirculatory blood flow velocity based on intelligent object identification

Ye¹,

Yin

et al. 2020

J. Biomed. Opt.

View full text Add to dashboard Cite

show abstract

“…The maximum blood velocity under avascularization condition was further decreased 50.2 % by mechanical stimulus. It should be noted that the typical velocity order of red blood cell in nailfold capillaries is about 500 ~ 1000 µm/s, which has been measured by a capillaroscope [18]. Capillary blood velocity in sub-epidermal region, obtained by OCDV, had almost the same order as that in nailfold although it was relatively smaller.…”

Section: Experiments and Test Subjectmentioning

confidence: 75%

<i>In vivo</i> Micro-Tomographic Visualization of Capillary Angio-Dynamics Around Upper Dermis Under Mechanical Stimulus Using Low Coherence Interferometer “Optical Coherence Doppler Velocigraphy”

Furukawa¹

2018

AJPA

View full text Add to dashboard Cite

The skin aging process, e.g. wrinkles and sagging, caused by not only aging but also ultraviolet irradiation, could be related to the depression of metabolic function. Therefore, an in vivo quantitative measurement of capillary blood flow velocity governing skin metabolism functionally, i.e. microcirculation, is crucial to clarify the skin aging and to create skincare products. The purpose of this study is to visualize the tomographic velocity of red blood cell in capillaries just below human epidermal skin using Optical Coherence Doppler Velocigraphy, namely OCDV. This was constructed on a low coherence interferometer, which could provide tomographic distribution of flow-modulated Doppler frequency by developing OCDV algorithm of Hilbert transform and adjacent autocorrelation. In order to validate OCDV system, this was in vivo applied to human forearm skin under respective mechanically stimulated conditions of control and avascularization. As a result, a crosssectional imaging of blood flow velocity was found to display not only morphological OCT images but also networks of capillary vasculature inside dermal tissue. It was confirmed that blood flow velocity further decreased in upper dermis under avascularization than control condition. Additionally, OCDV could provide a velocity map of blood flow having sensitivity to mechanical stimulus, so has strong efficacy to diagnose "Capillary Angio-Dynamics" of skin tissue. In conclusions, OCDV system could be quite useful for a micro-tomographic imaging of blood flow velocity of capillaries inside skin.

show abstract

“…In the field of capillaroscopy, the research activity in the field of nail capillaroscopy has been relatively richer. In this context, previous research has primarily focused on reducing small-scale movements by physically stabilizing the finger and the resulting video footage [ 22 , 23 ]. One common approach to achieve physical stabilization is the utilization of a metal bracket, which effectively minimizes finger movements in relation to the microscope.…”

Section: Related Workmentioning

confidence: 99%

Automated Stabilization, Enhancement and Capillaries Segmentation in Videocapillaroscopy

Taormina,

Raso,

Gentile

et al. 2023

Sensors

View full text Add to dashboard Cite

Oral capillaroscopy is a critical and non-invasive technique used to evaluate microcirculation. Its ability to observe small vessels in vivo has generated significant interest in the field. Capillaroscopy serves as an essential tool for diagnosing and prognosing various pathologies, with anatomic–pathological lesions playing a crucial role in their progression. Despite its importance, the utilization of videocapillaroscopy in the oral cavity encounters limitations due to the acquisition setup, encompassing spatial and temporal resolutions of the video camera, objective magnification, and physical probe dimensions. Moreover, the operator’s influence during the acquisition process, particularly how the probe is maneuvered, further affects its effectiveness. This study aims to address these challenges and improve data reliability by developing a computerized support system for microcirculation analysis. The designed system performs stabilization, enhancement and automatic segmentation of capillaries in oral mucosal video sequences. The stabilization phase was performed by means of a method based on the coupling of seed points in a classification process. The enhancement process implemented was based on the temporal analysis of the capillaroscopic frames. Finally, an automatic segmentation phase of the capillaries was implemented with the additional objective of quantitatively assessing the signal improvement achieved through the developed techniques. Specifically, transfer learning of the renowned U-net deep network was implemented for this purpose. The proposed method underwent testing on a database with ground truth obtained from expert manual segmentation. The obtained results demonstrate an achieved Jaccard index of 90.1% and an accuracy of 96.2%, highlighting the effectiveness of the developed techniques in oral capillaroscopy. In conclusion, these promising outcomes encourage the utilization of this method to assist in the diagnosis and monitoring of conditions that impact microcirculation, such as rheumatologic or cardiovascular disorders.

show abstract

High Speed Digital Video Capillaroscopy: Nailfold Capillary Shape Analysis and Red Blood Cell Velocity Measurement

Cited by 8 publications

References 24 publications

In-vivo full-field measurement of microcirculatory blood flow velocity based on intelligent object identification

In-vivo full-field measurement of microcirculatory blood flow velocity based on intelligent object identification

<i>In vivo</i> Micro-Tomographic Visualization of Capillary Angio-Dynamics Around Upper Dermis Under Mechanical Stimulus Using Low Coherence Interferometer “Optical Coherence Doppler Velocigraphy”

Automated Stabilization, Enhancement and Capillaries Segmentation in Videocapillaroscopy

Contact Info

Product

Resources

About

High Speed Digital Video Capillaroscopy: Nailfold Capillary Shape Analysis and Red Blood Cell Velocity Measurement

Cited by 8 publications

References 24 publications

In-vivo full-field measurement of microcirculatory blood flow velocity based on intelligent object identification

In-vivo full-field measurement of microcirculatory blood flow velocity based on intelligent object identification

&lt;i&gt;In vivo&lt;/i&gt; Micro-Tomographic Visualization of Capillary Angio-Dynamics Around Upper Dermis Under Mechanical Stimulus Using Low Coherence Interferometer “Optical Coherence Doppler Velocigraphy”

Automated Stabilization, Enhancement and Capillaries Segmentation in Videocapillaroscopy

Contact Info

Product

Resources

About

<i>In vivo</i> Micro-Tomographic Visualization of Capillary Angio-Dynamics Around Upper Dermis Under Mechanical Stimulus Using Low Coherence Interferometer “Optical Coherence Doppler Velocigraphy”