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Shucheng H, Zhou X, Du D, Li J, Yu C, Jiang X. Effects of 15% Azelaic Acid Gel in the Management of Post-Inflammatory Erythema and Post-Inflammatory Hyperpigmentation in Acne Vulgaris. Dermatol Ther (Heidelb) 2024; 14:1293-1314. [PMID: 38734843 PMCID: PMC11116308 DOI: 10.1007/s13555-024-01176-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Accepted: 04/22/2024] [Indexed: 05/13/2024] Open
Abstract
INTRODUCTION The aim of this study was to assess the efficacy and safety of 15% azelaic acid (AzA) gel in treating acne-induced post-inflammatory erythema (PIE) and post-inflammatory hyperpigmentation (PIH). The effects of 15% AzA gel on acne, skin barrier function, and quality of life were also evaluated. METHODS A total of 72 patients with mild to moderate acne were enrolled in a randomized, double-blind, placebo-controlled trial. Patients were divided into two groups: patients in the AzA group applied 15% AzA gel twice daily for 12 weeks, and those in the placebo group applied AzA-free gel. Clinical evaluations using non-invasive skin detection technologies, including VISIA skin analysis, dermoscopy, and skin physiological function tests, were performed at 0, 4, 8, and 12 weeks. Main outcome measures included the post-acne hyperpigmentation index (PAHPI), melanin, hemoglobin, individual typology angle, water content, transepidermal water loss, and sebum. Investigator Global Assessment) and Dermatology Life Quality Index (DLQI) assessments were conducted at weeks 0 and 12. Adverse reactions were recorded. RESULTS Of the 72 patients at study initiation, 60 completed the trial. At 8 and 12 weeks, patients in the AzA group showed significantly reduced PAHPI for PIE lesions compared to baseline and patients receiving placebo (P < 0.05). Patients in both groups exhibited reduced PIH lesions at weeks 8 and 12 that differed significantly from baseline (P < 0.05). Hemoglobin content decreased significantly in AzA-treated PIE lesions compared to those treated with placebo at week 12 (P < 0.05). Melanin content decreased significantly in AzA-treated PIH lesions at week 12 (P < 0.05). The AzA group showed higher improvement in DLQI (P < 0.05), and greater overall satisfaction (P < 0.05) compared to placebo. CONCLUSION The results indicate that 15% AzA gel effectively improved acne-induced PIE and PIH with minimal adverse reactions, making it a viable clinical application. In the study population, it had no adverse effects on skin barrier function and contributed positively to acne improvement and patient quality of life. TRIAL REGISTRATION This study was registered with the Chinese Clinical Trial Registry (ChiCTR.org.cn) under the identifier ChiCTR2300076959. The registration date was 25 October 2023, retrospectively registered.
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Affiliation(s)
- Huidi Shucheng
- Department of Dermatology and Venereology, West China Hospital, Sichuan University, Chengdu, 610041, China
- Laboratory of Dermatology, Clinical Institute of Inflammation and Immunology, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xinyu Zhou
- Department of Dermatology and Venereology, West China Hospital, Sichuan University, Chengdu, 610041, China
- Department of Dermatology, Nanbu People's Hospital, Nanchong, 637399, China
| | - Dan Du
- Department of Dermatology and Venereology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Jiaqi Li
- Department of Dermatology and Venereology, West China Hospital, Sichuan University, Chengdu, 610041, China
- Laboratory of Dermatology, Clinical Institute of Inflammation and Immunology, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Chenyang Yu
- Department of Dermatology and Venereology, West China Hospital, Sichuan University, Chengdu, 610041, China
- Laboratory of Dermatology, Clinical Institute of Inflammation and Immunology, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Xian Jiang
- Department of Dermatology and Venereology, West China Hospital, Sichuan University, Chengdu, 610041, China.
- Laboratory of Dermatology, Clinical Institute of Inflammation and Immunology, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, 610041, China.
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Lin CH, Lukas BE, Rajabi-Estarabadi A, May JR, Pang Y, Puyana C, Tsoukas M, Avanaki K. Rapid measurement of epidermal thickness in OCT images of skin. Sci Rep 2024; 14:2230. [PMID: 38278852 PMCID: PMC10817904 DOI: 10.1038/s41598-023-47051-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 11/08/2023] [Indexed: 01/28/2024] Open
Abstract
Epidermal thickness (ET) changes are associated with several skin diseases. To measure ET, segmentation of optical coherence tomography (OCT) images is essential; manual segmentation is very time-consuming and requires training and some understanding of how to interpret OCT images. Fast results are important in order to analyze ET over different regions of skin in rapid succession to complete a clinical examination and enable the physician to discuss results with the patient in real time. The well-known CNN-graph search (CNN-GS) methodology delivers highly accurate results, but at a high computational cost. Our objective was to build a computational core, based on CNN-GS, able to accurately segment OCT skin images in real time. We accomplished this by fine-tuning the hyperparameters, testing a range of speed-up algorithms including pruning and quantization, designing a novel pixel-skipping process, and implementing the final product with efficient use of core and threads on a multicore central processing unit (CPU). We name this product CNN-GS-skin. The method identifies two defined boundaries on OCT skin images in order to measure ET. We applied CNN-GS-skin to OCT skin images, taken from various body sites of 63 healthy individuals. Compared with CNN-GS, our described method reduced computation time by 130 [Formula: see text] with minimal reduction in ET determination accuracy (from 96.38 to 94.67%).
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Affiliation(s)
- Chieh-Hsi Lin
- Department of Computer Science, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Brandon E Lukas
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Ali Rajabi-Estarabadi
- Dr. Phillip Frost Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
- Department of Dermatology, Broward Health Medical Center, Fort Lauderdale, FL, USA
| | - Julia Rome May
- University of Illinois College of Medicine, Chicago, IL, 60607, USA
| | - Yanzhen Pang
- University of Illinois College of Medicine, Chicago, IL, 60607, USA
| | - Carolina Puyana
- Department of Dermatology, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Maria Tsoukas
- Department of Dermatology, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Kamran Avanaki
- Richard and Loan Hill Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, 60607, USA.
- Department of Dermatology, University of Illinois at Chicago, Chicago, IL, 60607, USA.
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Zdrada-Nowak J, Stolecka-Warzecha A, Odrzywołek W, Rusztowicz M, Błońska-Fajfrowska B, Wilczyński S. The assessment of moderate acne vulgaris face skin using blood perfusion and hyperspectral imaging-A pilot study. J Cosmet Dermatol 2023; 22:3143-3151. [PMID: 37248648 DOI: 10.1111/jocd.15811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 04/03/2023] [Accepted: 04/28/2023] [Indexed: 05/31/2023]
Abstract
BACKGROUND Microcirculation is the flow of blood through the smallest vessels in the circulatory system. Capillaries respond to various pathologies much earlier than arteries and veins, the changes which indicate that the disease is already developing. Careful monitoring of the functioning of the capillary system often allows the detection of in vivo disorders at an early stage. AIMS The aim of the study was to evaluate the microcirculation within acne lesions. A noninvasive method of semi-quantitative blood perfusion measurement based on laser speckle contrast analysis (LASCA) and a quantitative assessment of the acne severity using the hyperspectral imaging method supported by image analysis and processing methods were used. PATIENTS/METHOD The acne lesion perfusion was compared to the healthy skin perfusion of the control group. The reflectance in the range from 400 to 1000 nm was also compared for acne lesions and healthy skin. A dedicated version of the algorithm based on the gray-level co-occurrence matrix was used to compare differences between acne lesions and healthy skin. RESULTS Blood perfusion in acne lesions is on average 117% higher than in healthy skin. The reflectance of acne lesions was lower in the range of 400-600 nm compared to the healthy skin. A statistically significant decrease in the reflectance of acne lesions was demonstrated for wavelengths: 434, 549, and 588 nm. CONCLUSIONS Increased blood perfusion in acne lesions compared to healthy skin suggests increased chemotaxis of inflammatory cells and wound healing. Decrease points in skin reflectance resemble the absorption peaks for hemoglobin and coproporphyrin III produced by Cutibacterium acnes. Thus, the proposed methods may serve not only for the early detection of acne lesions, before they manifest themselves clinically for the naked eye, but may also be a tool for quantifying the effectiveness of acne treatment.
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Affiliation(s)
- Julita Zdrada-Nowak
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Anna Stolecka-Warzecha
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Wiktoria Odrzywołek
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Monika Rusztowicz
- Department of Health Sciences, Institute of Health Sciences, University of Opole, Opole, Poland
| | - Barbara Błońska-Fajfrowska
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Sławomir Wilczyński
- Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland
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Li D, Sun Y, Ren X, Zhou N, Li L, He G, Ma S, Wang Y. Dynamic evaluation of pathological changes in a mouse acne model by optical imaging technology. Exp Dermatol 2023; 32:1350-1360. [PMID: 37183301 DOI: 10.1111/exd.14826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 03/27/2023] [Accepted: 04/19/2023] [Indexed: 05/16/2023]
Abstract
Acne vulgaris is a disorder of the pilosebaceous unit that is primarily caused by hyperseborrhoea, colonization with Propionibacterium acnes, hyperkeratosis and an inflammatory response. Existing pharmacodynamic assessment methods primarily focus on a single causative factor at a certain time point, making it difficult to assess multiple factors simultaneously in real time. Therefore, it is crucial to establish a dynamic and nondestructive method for the assessment of acne in vivo. This study utilized four-dimensional optical imaging techniques to assess the pathogenic factors and pathological progression of acne. LSCI was employed to measure blood flow; TPEF was used to observe inflammatory changes (NAD(P)H) in epidermal granular layer cells and structural changes in collagen fibres in the dermal layer. Additionally, the dermatoscope was used to investigate the micro-characterization of the lesions. We observed that the epidermis in the lesion area was thickened, hair follicles were keratinized, and there was obvious inflammation and blood flow aggregation by optical imaging technology. Based on these findings, the pathological progression of this acne model could be divided into the inflammation phase, accompanied by bacterial colonization, and the reparative phase. These results provide a new perspective for the assessment of acne and offer an experimental basis for the selection of precise drugs for clinical use.
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Affiliation(s)
- Dongying Li
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yanan Sun
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xing Ren
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
| | - Na Zhou
- Department of Immunology and Microbiology, School of Life Science, Beijing University of Chinese Medicine, Beijing, China
| | - Lu Li
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
| | - Gaiying He
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
| | - Shuhua Ma
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yi Wang
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
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Liao J, Yang S, Zhang T, Li C, Huang Z. A hand-held optical coherence tomography angiography scanner based on angiography reconstruction transformer networks. JOURNAL OF BIOPHOTONICS 2023; 16:e202300100. [PMID: 37264544 DOI: 10.1002/jbio.202300100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/18/2023] [Accepted: 05/24/2023] [Indexed: 06/03/2023]
Abstract
Optical coherence tomography angiography (OCTA) has successfully demonstrated its viability for clinical applications in dermatology. Due to the high optical scattering property of skin, extracting high-quality OCTA images from skin tissues requires at least six-repeated scans. While the motion artifacts from the patient and the free hand-held probe can lead to a low-quality OCTA image. Our deep-learning-based scan pipeline enables fast and high-quality OCTA imaging with 0.3-s data acquisition. We utilize a fast scanning protocol with a 60 μm/pixel spatial interval rate and introduce angiography-reconstruction-transformer (ART) for 4× super-resolution of low transverse resolution OCTA images. The ART outperforms state-of-the-art networks in OCTA image super-resolution and provides a lighter network size. ART can restore microvessels while reducing the processing time by 85%, and maintaining improvements in structural similarity and peak-signal-to-noise ratio. This study represents that ART can achieve fast and flexible skin OCTA imaging while maintaining image quality.
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Affiliation(s)
- Jinpeng Liao
- School of Science and Engineering, University of Dundee, Scotland, UK
| | - Shufan Yang
- School of Computing, Engineering and Built Environment, Edinburgh Napier University, Edinburgh, UK
- Research Department of Orthopaedics and Musculoskeletal Science, University College London, UK
| | - Tianyu Zhang
- School of Science and Engineering, University of Dundee, Scotland, UK
| | - Chunhui Li
- School of Science and Engineering, University of Dundee, Scotland, UK
| | - Zhihong Huang
- School of Science and Engineering, University of Dundee, Scotland, UK
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Al-Chaer RN, Bouazzi D, Jemec G, Mogensen M. Confocal microscopy and optical coherence tomography of inflammatory skin diseases in hairs and pilosebaceous units: A systematic review. Exp Dermatol 2023. [PMID: 37140216 DOI: 10.1111/exd.14830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 04/14/2023] [Accepted: 04/23/2023] [Indexed: 05/05/2023]
Abstract
Common skin disorders such as acne vulgaris, rosacea and folliculitis are bothersome prevalent inflammatory diseases of hair follicles that can easily be investigated bedside using optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) with micrometre resolution, opening a novel era for high-resolution hair follicle diagnostics and quantitative treatment evaluation. EMBASE, PubMed and Web of Science were searched until 5 January 2023 to identify all studies imaging hair follicle characteristics by RCM and OCT for diagnosis and monitoring of treatment in hair follicle-based skin disorders. This study followed PRISMA guidelines. After inclusion of articles, methodological quality was assessed using the QUADAS-2 critical appraisal checklist. Thirty-nine in vivo studies (33 RCM and 12 OCT studies) were included. The studies focused on acne vulgaris, rosacea, alopecia areata, hidradenitis suppurativa, folliculitis, folliculitis decalvans, lichen planopilaris, discoid lupus erythemasus, frontal fibrosing alopecia and keratosis pilaris. Inter- and perifollicular morphology including number of demodex mites, hyperkeratinization, inflammation and vascular morphology could be assessed by RCM and OCT in all included skin disorders. Methodological study quality was low, and interstudy outcome variability was high. Quality assessment showed high or unclear risk of bias in 36 studies. Both RCM and OCT visualize quantitative features as size, shape, content and abnormalities of hair follicles, and have potential to support clinical diagnosis and evaluate treatment effects. However, larger studies with better methodological quality are needed to implement RCM and OCT directly into clinical practice.
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Affiliation(s)
- Rami Nabil Al-Chaer
- Department of Dermatology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
| | - Dorra Bouazzi
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark
| | - Gregor Jemec
- Department of Dermatology, Zealand University Hospital, Roskilde, Denmark
| | - Mette Mogensen
- Department of Dermatology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
- Department of Clinical Medicine, The Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Ji Y, Yang S, Zhou K, Lu J, Wang R, Rocliffe HR, Pellicoro A, Cash JL, Li C, Huang Z. Semisupervised representative learning for measuring epidermal thickness in human subjects in optical coherence tomography by leveraging datasets from rodent models. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:085002. [PMID: 35982528 PMCID: PMC9388694 DOI: 10.1117/1.jbo.27.8.085002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
SIGNIFICANCE Morphological changes in the epidermis layer are critical for the diagnosis and assessment of various skin diseases. Due to its noninvasiveness, optical coherence tomography (OCT) is a good candidate for observing microstructural changes in skin. Convolutional neural network (CNN) has been successfully used for automated segmentation of the skin layers of OCT images to provide an objective evaluation of skin disorders. Such method is reliable, provided that a large amount of labeled data is available, which is very time-consuming and tedious. The scarcity of patient data also puts another layer of difficulty to make the model more generalizable. AIM We developed a semisupervised representation learning method to provide data augmentations. APPROACH We used rodent models to train neural networks for accurate segmentation of clinical data. RESULT The learning quality is maintained with only one OCT labeled image per volume that is acquired from patients. Data augmentation introduces a semantically meaningful variance, allowing for better generalization. Our experiments demonstrate the proposed method can achieve accurate segmentation and thickness measurement of the epidermis. CONCLUSION This is the first report of semisupervised representative learning applied to OCT images from clinical data by making full use of the data acquired from rodent models. The proposed method promises to aid in the clinical assessment and treatment planning of skin diseases.
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Affiliation(s)
- Yubo Ji
- University of Dundee, School of Science and Engineering, Dundee, United Kingdom
| | - Shufan Yang
- Edinburgh Napier University, School of Computing, Edinburgh, United Kingdom
- University of Glasgow, Center of Medical and Industrial Ultrasonics, Glasgow, United Kingdom
| | - Kanheng Zhou
- University of Dundee, School of Science and Engineering, Dundee, United Kingdom
| | - Jie Lu
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Ruikang Wang
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Holly R. Rocliffe
- The University of Edinburgh, The Queen’s Medical Research Institute, MRC Centre for Inflammation Research, Edinburgh, United Kingdom
| | - Antonella Pellicoro
- The University of Edinburgh, The Queen’s Medical Research Institute, MRC Centre for Inflammation Research, Edinburgh, United Kingdom
| | - Jenna L. Cash
- The University of Edinburgh, The Queen’s Medical Research Institute, MRC Centre for Inflammation Research, Edinburgh, United Kingdom
| | - Chunhui Li
- University of Dundee, School of Science and Engineering, Dundee, United Kingdom
| | - Zhihong Huang
- University of Dundee, School of Science and Engineering, Dundee, United Kingdom
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Jurairattanaporn N, Suchonwanit P, Rattananukrom T, Vachiramon V. A Comparative Study of Dermatoscopic Features of Acne-related Postinflammatory Hyperpigmentation in Facial and Nonfacial Areas in Asian Patients. THE JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY 2022; 15:16-21. [PMID: 36061483 PMCID: PMC9436223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
BACKGROUND Postinflammatory hyperpigmentation (PIH) is a common problem, especially in patients with darker skin tones. It can occur on any area of the body following external injuries or intense inflammatory conditions. However, there is limited evidence regarding the differences in dermatoscopic patterns between facial acne-related PIH and nonfacial acne-related PIH. OBJECTIVE We sought to determine the dermatoscopic features of acne-related PIH in facial and nonfacial areas in an Asian population. METHODS Patients with acne-related PIH in both facial and nonfacial areas were enrolled. Baseline demographic data, location, and duration of PIH were recorded. Dermatoscopic and clinical pictures of each patient were taken from the darkest PIH lesions of both areas. Differences in dermatoscopic patterns were analyzed. RESULTS Fifty patients were enrolled. The mean age was 26.74 (+ 6.75) years, and the Fitzpatrick Skin Types were III (66%) and IV (34%). In terms of morphological patterns of melanin, nonfacial PIH showed a significantly more regular pigment network than facial PIH (100% vs. 20%, p<0.05), while facial PIH exhibited a more pseudoreticular pigment network than nonfacial PIH (70% vs. 0%, p<0.05). In terms of vascularity, facial PIH demonstrated more telangiectasia and an increased vascular component compared to nonfacial PIH (56% vs. 16%, p<0.05). Moreover, hypopigmentation within the PIH lesion was demonstrated in both facial and nonfacial lesions (42% vs. 50%, p=0.541). CONCLUSION Acne-related PIH in facial and nonfacial areas showed different morphological pigment patterns and degrees of vascularity. Dermatoscopic examination should be performed before treatment initiation.
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Affiliation(s)
- Natthachat Jurairattanaporn
- Dr. Jurairattanaporn is also with the Department of Dermatology, Faculty of Medicine at Srinakharinwirot University in Bangkok, Thailand
| | - Poonkiat Suchonwanit
- All authors are with the Division of Dermatology, the Faculty of Medicine Ramathibodi Hospital at Mahidol University in Bangkok, Thailand
| | - Teerapong Rattananukrom
- All authors are with the Division of Dermatology, the Faculty of Medicine Ramathibodi Hospital at Mahidol University in Bangkok, Thailand
| | - Vasanop Vachiramon
- All authors are with the Division of Dermatology, the Faculty of Medicine Ramathibodi Hospital at Mahidol University in Bangkok, Thailand
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Cardinell JL, Ramjist JM, Chen C, Shi W, Nguyen NQ, Yeretsian T, Choi M, Chen D, Clark DS, Curtis A, Kim H, Faughnan ME, Yang VXD. Quantification metrics for telangiectasia using optical coherence tomography. Sci Rep 2022; 12:1805. [PMID: 35110554 PMCID: PMC8810896 DOI: 10.1038/s41598-022-05272-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 02/17/2021] [Indexed: 12/02/2022] Open
Abstract
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder that causes vascular malformations throughout the body. The most prevalent and accessible of these lesions are found throughout the skin and mucosa, and often rupture causing bleeding and anemia. A recent increase in potential HHT treatments have created a demand for quantitative metrics that can objectively measure the efficacy of new and developing treatments. We employ optical coherence tomography (OCT)—a high resolution, non-invasive imaging modality in a novel pipeline to image and quantitatively characterize dermal HHT lesion behavior over time or throughout the course of treatment. This study is aimed at detecting detailed morphological changes of dermal HHT lesions to understand the underlying dynamic processes of the disease. We present refined metrics tailored for HHT, developed from a pilot study using 3 HHT patients and 6 lesions over the course of multiple imaging dates, totalling to 26 lesion images. Preliminary results from these lesions are presented in this paper alongside representative OCT images. This study provides a new objective method to analyse and understand HHT lesions using a minimally invasive, accessible, cost-effective, and efficient imaging modality with quantitative metrics describing morphology and blood flow.
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Affiliation(s)
- Jillian L Cardinell
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.
| | - Joel M Ramjist
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada
| | - Chaoliang Chen
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.,Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Weisong Shi
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.,Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Nhu Q Nguyen
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada
| | - Tiffany Yeretsian
- Physical Sciences Platform, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Matthew Choi
- Physical Sciences Platform, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, ON, Canada
| | - David Chen
- Physical Sciences Platform, Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Dewi S Clark
- Toronto HHT Centre, Division of Respirology, Department of Medicine, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada
| | - Anne Curtis
- Division of Dermatology, University of Toronto, Toronto, ON, Canada
| | - Helen Kim
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Marie E Faughnan
- Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | - Victor X D Yang
- Deparment of Electrical, Computer, and Biomedical Engineering, Ryerson University, Toronto, ON, Canada.,Department of Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China.,Department of Surgery, Division of Neurosurgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
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10
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Ji Y, Zhou K, Ibbotson SH, Wang RK, Li C, Huang Z. A novel automatic 3D stitching algorithm for optical coherence tomography angiography and its application in dermatology. JOURNAL OF BIOPHOTONICS 2021; 14:e202100152. [PMID: 34260830 DOI: 10.1002/jbio.202100152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/12/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
Optical coherence tomography (OCT) and OCT angiography (OCTA) techniques offer numerous advantages in clinical skin applications but the field of view (FOV) of current commercial systems are relatively limited to cover the entire skin lesion. The typical method to expand the FOV is to apply wide field objective lens. However, lateral resolution is often sacrificed when scanning with these lenses. To overcome this drawback, we developed an automated 3D stitching method for creating high-resolution skin structure and vascular volumes with large field of view, which was realized by montaging multiple adjacent OCT and OCTA volumes. The proposed stitching method is demonstrated by montaging 3 × 3 OCT and OCTA volumes (nine OCT/OCTA volumes as one data set with each volume covers 2.5 cm × 2.5 cm area) of healthy thin and thick skin from six volunteers. The proposed stitching protocol achieves high flexibility and repeatable for all the participants. Moreover, according to evaluation of structural similarity index and feature similarity index, our proposed stitched result has a superior similarity to single scanning protocol in large-scaled. We had also verified its improved performance through assessing metrics of vessel contrast-noise-ratio (CNR) from 2.07 ± 0.44 (single large-scaled scanning protocol) to 3.05 ± 0.51 (proposed 3 × 3 sub-volume stitching method).
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Affiliation(s)
- Yubo Ji
- School of Science and Engineering, University of Dundee, Dundee, Scotland, UK
| | - Kanheng Zhou
- School of Science and Engineering, University of Dundee, Dundee, Scotland, UK
| | - Sally Helen Ibbotson
- University of Dundee, Photobiology Unit, Ninewells Hospital and Medical School, Dundee, UK
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - Chunhui Li
- School of Science and Engineering, University of Dundee, Dundee, Scotland, UK
| | - Zhihong Huang
- School of Science and Engineering, University of Dundee, Dundee, Scotland, UK
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Wamsley CE, Kislevitz M, Barillas J, Basci D, Kandagatla V, Hitchcock T, Akgul Y, Kenkel J. A Single-Center Trial to Evaluate the Efficacy and Tolerability of Four Microneedling Treatments on Fine Lines and Wrinkles of Facial and Neck Skin in Subjects With Fitzpatrick Skin Types I-IV: An Objective Assessment Using Noninvasive Devices and 0.33-mm Microbiopsies. Aesthet Surg J 2021; 41:NP1603-NP1618. [PMID: 33656167 DOI: 10.1093/asj/sjab052] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Although ablative techniques are the standard of care for the treatment of fine lines and wrinkles, microneedling offers a minimally invasive alternative. OBJECTIVES The purpose of this study was to assess the efficacy of microneedling on facial and neck fine lines and wrinkles. METHODS Thirty-five subjects between 44 and 65 years old with Fitzpatrick skin types I to IV received 4 monthly microneedling treatments over the face and neck. Subjects returned 1 and 3 months posttreatment. At every visit, high-resolution ultrasonography and optical coherence tomography were performed, and transepidermal water loss and skin elasticity were measured. Microbiopsies (0.33 mm) were collected pretreatment, before the fourth treatment and 3 months posttreatment. RESULTS Thirty-two subjects (30 females, 2 males) completed all 7 visits. Facial dermal and epidermal density increased 101.86% and 19.28%, respectively, from baseline at 3 months posttreatment. Facial elasticity increased 28.2% from baseline at 3 months posttreatment. Facial attenuation coefficient increased 15.65% and 17.33% at 1 and 3 months posttreatment, respectively. At study completion, blood flow at a depth of 300 µm decreased 25.8% in the face and 42.3% in the neck. Relative collagen type III and elastin gene expression was statistically higher 3 months posttreatment. However, total elastin protein levels were unchanged from baseline values. Dermal muscle formation was observed in 58% of biopsies extracted 3 months posttreatment compared with 15.3% at baseline. CONCLUSIONS The results illustrate the effects of microneedling treatments. Noninvasive measurements and biopsy data showed changes in skin architecture and collagen/elastin gene expression, suggesting skin rejuvenation, with new extracellular matrix production and muscle formation. LEVEL OF EVIDENCE: 3
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Affiliation(s)
- Christine E Wamsley
- Department of Plastic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Mikaela Kislevitz
- Department of General Surgery, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Jennifer Barillas
- Department of Plastic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Deniz Basci
- Department of Plastic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Vishal Kandagatla
- Department of Plastic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | | | - Yucel Akgul
- Department of Plastic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jeffrey Kenkel
- Department of Plastic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
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Imaging Motion: A Comprehensive Review of Optical Coherence Tomography Angiography. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1310:343-365. [PMID: 33834441 DOI: 10.1007/978-981-33-6064-8_12] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Optical coherence tomography (OCT) is a three-dimensional (3-D) optical imaging technology that provides noninvasive, micrometer resolution images of structural interiors within biological samples with an approximately 1 ~ 2 mm penetration depth. Over the last decades, advances in OCT have revolutionized biomedical imaging by demonstrating a potential of optical biopsy in preclinical and clinical settings. Recently, functional OCT imaging has shown a promise as angiography to visualize cell-perfused vasculatures in the tissue bed in vivo without requiring any exogenous contrast agents. This new technology termed OCT angiography (OCTA) possesses a unique imaging capability of delineating tissue morphology and blood or lymphatic vessels down to capillaries at real-time acquisition rates. For the past 10 years since 2007, OCTA has been proven to be a useful tool to identify disorder or dysfunction in tissue microcirculation from both experimental animal studies and clinical studies in ophthalmology and dermatology. In this section, we overview about OCTA including a basic principle of OCTA explained with simple optical physics, and its scan protocols and post-processing algorithms for acquisition of angiography. Then, potential and challenge of OCTA for clinical settings are shown with outcomes of human studies.
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13
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Nkengne A, Pellacani G, Ciardo S, De Carvalho N, Vié K. Visible characteristics and structural modifications relating to enlarged facial pores. Skin Res Technol 2020; 27:560-568. [PMID: 33215751 DOI: 10.1111/srt.12984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 10/30/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Many factors relate to enlargement and visibility of facial pores. However, how enlargement relates to modification of the skin structure is still poorly analysed. Therefore, our aim was to characterise the visible features and the micro-environment of facial pores. MATERIALS AND METHODS We recruited 160 women, half of them with normal-size facial pores, the other half presenting enlarged pores. We analysed their right cheek using standardised photography, in vivo reflectance microscopy and optical coherence tomography. RESULTS If the area of pores is indeed the most differentiating visible characteristic, enlarged facial pores are also denser and more contrasted. At the structural level, enlarged facial pores present a more regular organisation of keratinocytes, an irregular dermo-epidermal junction and a higher attenuation of collagen between the surface and deeper layers. Still, the most relevant alterations of enlarged facial pores are the presence of bright tubular structures surrounding hair follicles and enlarged hair shafts. CONCLUSION These observations suggest that alterations of the stroma could result in altered skin tensions, leading to the dilation of the infundibulum and enlarged hair shaft. The modified tension would also explain the more regular organisation of the keratinocytes and the irregular dermo-epidermal junction.
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Affiliation(s)
| | - Giovanni Pellacani
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Silvana Ciardo
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Nathalie De Carvalho
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
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Li S, Mohamedi AH, Senkowsky J, Nair A, Tang L. Imaging in Chronic Wound Diagnostics. Adv Wound Care (New Rochelle) 2020; 9:245-263. [PMID: 32226649 PMCID: PMC7099416 DOI: 10.1089/wound.2019.0967] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 05/14/2019] [Indexed: 01/18/2023] Open
Abstract
Significance: Chronic wounds affect millions of patients worldwide, placing a huge burden on health care resources. Although significant progress has been made in the development of wound treatments, very few advances have been made in wound diagnosis. Recent Advances: Standard imaging methods like computed tomography, single-photon emission computed tomography, magnetic resonance imaging, terahertz imaging, and ultrasound imaging have been widely employed in wound diagnostics. A number of noninvasive optical imaging modalities like optical coherence tomography, near-infrared spectroscopy, laser Doppler imaging, spatial frequency domain imaging, digital camera imaging, and thermal and fluorescence imaging have emerged over the years. Critical Issues: While standard diagnostic wound imaging modalities provide valuable information, they cannot account for dynamic changes in the wound environment. In addition, they lack the capability to predict the healing outcome. Thus, there remains a pressing need for more efficient methods that can not only indicate the current state of the wound but also help determine whether the wound is on track to heal normally. Future Directions: Many imaging probes have been fabricated and shown to provide real-time assessment of tissue microenvironment and inflammatory responses in vivo. These probes have been demonstrated to noninvasively detect various changes in the wound environment, which include tissue pH, reactive oxygen species, fibrin deposition, matrix metalloproteinase production, and macrophage accumulation. This review summarizes the creation of these probes and their potential implications in wound monitoring.
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Affiliation(s)
- Shuxin Li
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas
| | - Ali H. Mohamedi
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas
| | | | | | - Liping Tang
- Department of Bioengineering, University of Texas at Arlington, Arlington, Texas
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15
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Baik JW, Kim JY, Cho S, Choi S, Kim J, Kim C. Super Wide-Field Photoacoustic Microscopy of Animals and Humans In Vivo. IEEE TRANSACTIONS ON MEDICAL IMAGING 2020; 39:975-984. [PMID: 31484110 DOI: 10.1109/tmi.2019.2938518] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Acoustic-resolution photoacoustic micro-scopy (AR-PAM) is an emerging biomedical imaging modality that combines superior optical sensitivity and fine ultrasonic resolution in an optical quasi-diffusive regime (~1-3 mm in tissues). AR-PAM has been explored for anatomical, functional, and molecular information in biological tissues. Heretofore, AR-PAM systems have suffered from a limited field-of-view (FOV) and/or slow imaging speed, which have precluded them from routine preclinical and clinical applications. Here, we demonstrate an advanced AR-PAM system that overcomes both limitations of previous AR-PAM systems. The new AR-PAM system demonstrates a super wide-field scanning that utilized a 1-axis water-proofing microelectromechanical systems (MEMS) scanner integrated with two linear stepper motor stages. We achieved an extended FOV of 36 ×80 mm2 by mosaicking multiple volumetric images of 36 ×2.5 mm2 with a total acquisition time of 224 seconds. For one volumetric data (i.e., 36 ×2.5 mm2), the B-scan imaging speed over the short axis (i.e., 2.5 mm) was 83 Hz in humans. The 3D volumetric image was also provided by using MEMS mirror scanning along the X-axis and stepper-motor scanning along the Y-axis. The super-wide FOV mosaic image was realized by registering and merging all individual volumetric images. Finally, we obtained multi-plane whole-body in-vivo PA images of small animals, illustrating distinct multi-layered structures including microvascular networks and internal organs. Importantly, we also visualized microvascular networks in human fingers, palm, and forearm successfully. This advanced MEMS-AR-PAM system could potentially enable hitherto not possible wide preclinical and clinical applications.
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16
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Use of Optical Coherence Tomography (OCT) in Aesthetic Skin Assessment—A Short Review. Lasers Surg Med 2020; 52:699-704. [DOI: 10.1002/lsm.23219] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2020] [Indexed: 12/28/2022]
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17
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Gold MH, Wilson A, Mordon SR. Treatment of acne scarring with a novel dual-wavelength laser. J Cosmet Dermatol 2019; 18:1290-1293. [PMID: 31290591 DOI: 10.1111/jocd.13068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/17/2019] [Indexed: 01/24/2023]
Abstract
BACKGROUND Facial acne scarring is a prevalent disease with both physical and psychosocial sequelae. AIMS This study aims to evaluate an innovative solid state dual wavelength 1,319 and 589 nm laser, which does not require consumable dye, for the treatment of acne scars. PATIENTS/METHODS A total of 12 patients (11 female, 1 man - Fitzpatrick skin phototypes II & III) with acne scar for more than one year, were treated with 1319 nm and subsequently by 589 nm, all having four-sessions, one every other week. A full face was covered in approximately 30 minutes. Acne scars were scored by one physician evaluator using the ECCA grading scale before, 2 weeks after each treatment and 1 month and 6 months after the 4th treatment. Safety was measured by recording subject discomfort scores and adverse effects. RESULTS 12 subjects were enrolled into the study, 10 completed all 4 treatments and 2 were lost to follow up. Fluence used was 28 J/cm² ± 2.4 J/cm² at 1,319 nm and 16 ± 2.9 J/cm² at 589 nm. At baseline, mean ECCA score was 98 ± 23. This score was reduced to 88 ± 30 (p<0.02), after one session, to 68 ± 21 (p<0.01) after 2 sessions, to 58 ± 17 (p<0.01) after 3 sessions to reach 58 ± 15 (p<0.01) 1 month after the 4th and finally 66 ± 11 (p<0.01) at 6 month follow up. This observation corresponds respectively to 14%, 33%, 42%, 40% and 30% reduction of the ECCA score. Only one patient (ECCA score: 120) did not improve after 3 sessions. Slight to moderate erythema was sometimes observed without dryness or bruising. No or minimal burning or stinging was reported. No crust was observed. CONCLUSION Improvement in scarring was noted in almost all patients with minimal discomfort and minimal downtime. Combining both minimal side effects with effective acne scar reduction, this laser appears to be highly effective. Long-term evaluation remains necessary to confirm the efficacy of this new laser.
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Affiliation(s)
| | - April Wilson
- Tennessee Clinical Research Center, Nashville, TN, USA
| | - Serge R Mordon
- University Lille, Inserm, CHU Lille, U1189-ONCO-THAI - Image Assisted Laser Therapy for Oncology, Lille, France
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18
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Hermsmeier M, Sawant T, Chowdhury K, Nagavarapu U, Chan KF. First Use of Optical Coherence Tomography on In Vivo Inflammatory Acne-Like Lesions: A Murine Model. Lasers Surg Med 2019; 52:207-217. [PMID: 31347184 DOI: 10.1002/lsm.23140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2019] [Indexed: 01/19/2023]
Abstract
BACKGROUND AND OBJECTIVES Successful outcomes of clinical studies for acne vulgaris depend greatly on achieving statistically significant reduction in acne lesion count and improvement in Investigator's Global Assessment score of the investigational drug product against its vehicle control. To date, there has not been a validated preclinical acne model to evaluate investigational drug products in order to improve the probability of clinical success. An inflammatory acne-like lesion mouse model developed in-house has previously been used for clinical guidance in our drug development program. In this study, we aim to implement and assess the adequacy of swept-source optical coherence tomography (SS-OCT) in quantifying the dynamic changes in inflammatory acne-like lesions. STUDY DESIGN/MATERIALS AND METHODS Live Propionibacterium acnes bacteria were injected intradermally resulting in inflammatory acne-like lesions. Topical 1% and 2% minocycline gels were applied to the lesions in separate groups once daily for 2 weeks and compared with vehicle and untreated control groups. The growth of these lesions was monitored and measured with a ruler (height)/microcaliper (width)-an approach previously developed, and with SS-OCT. The reliability of the two methods were assessed. Acquired OCT images across the apex of these inflammatory lesions were statistically analyzed for lesion volume reduction from baseline as well as between the treatment groups and the control groups. RESULTS The OCT technique allowed for reliable lesion volume analysis with varying conic profiles. After 14 days of topical minocycline treatments (1%, 2% minocycline), statistically significant reduction in lesion volume (P ≤ 0.05) based on OCT image analysis was observed compared with untreated and vehicle control groups as well as compared with baseline measurements. Under the right conditions, some morphological aspects of the P. acnes injection site were discernible within the skin in images captured with OCT. CONCLUSIONS We demonstrated the first use of SS-OCT in evaluating in vivo inflammatory acne-like lesions in a murine model. Our findings support the use of OCT in assessing lesion size and evolution of P. acnes injection sites non-invasively in preclinical in vivo studies, which could potentially lead to more consistent and predictable outcomes in clinical development. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Maiko Hermsmeier
- Research and Development, BioPharmX, Inc., 115 Nicholson Lane, San Jose, California, 95134
| | - Tanvee Sawant
- Research and Development, BioPharmX, Inc., 115 Nicholson Lane, San Jose, California, 95134
| | - Khadiza Chowdhury
- Research and Development, BioPharmX, Inc., 115 Nicholson Lane, San Jose, California, 95134
| | - Usha Nagavarapu
- Research and Development, BioPharmX, Inc., 115 Nicholson Lane, San Jose, California, 95134
| | - Kin F Chan
- Research and Development, BioPharmX, Inc., 115 Nicholson Lane, San Jose, California, 95134
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19
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Liu M, Drexler W. Optical coherence tomography angiography and photoacoustic imaging in dermatology. Photochem Photobiol Sci 2019; 18:945-962. [PMID: 30735220 DOI: 10.1039/c8pp00471d] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Optical coherence tomography angiography (OCTA) is a relatively novel functional extension of the widely accepted ophthalmic imaging tool named optical coherence tomography (OCT). Since OCTA's debut in ophthalmology, researchers have also been trying to expand its translational application in dermatology. The ability of OCTA to resolve microvasculature has shown promising results in imaging skin diseases. Meanwhile, photoacoustic imaging (PAI), which uses laser pulse induced ultrasound waves as the signal, has been studied to differentiate human skin layers and to help in skin disease diagnosis. This perspective article gives a short review of OCTA and PAI in the field of photodermatology. After an introduction to the principles of OCTA and PAI, we describe the most updated results of skin disease imaging using these two optical imaging modalities. We also place emphasis on dual modality imaging combining OCTA and photoacoustic tomography (PAT) for dermatological applications. In the end, the challenges and prospects of these two imaging modalities in dermatology are discussed.
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Affiliation(s)
- Mengyang Liu
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria.
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20
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Manfredini M, Bettoli V, Sacripanti G, Farnetani F, Bigi L, Puviani M, Corazza M, Pellacani G. The evolution of healthy skin to acne lesions: a longitudinal,
in vivo
evaluation with reflectance confocal microscopy and optical coherence tomography. J Eur Acad Dermatol Venereol 2019; 33:1768-1774. [DOI: 10.1111/jdv.15641] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/03/2019] [Indexed: 11/26/2022]
Affiliation(s)
- M. Manfredini
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
- Department of Medical Sciences Section of Dermatology University of Ferrara Ferrara Italy
- Dermatology Unit Nuovo Ospedale Civile di Sassuolo Sassuolo Italy
| | - V. Bettoli
- Department of Medical Sciences Section of Dermatology University of Ferrara Ferrara Italy
| | - G. Sacripanti
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
| | - F. Farnetani
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
| | - L. Bigi
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
| | - M. Puviani
- Dermatology Unit Nuovo Ospedale Civile di Sassuolo Sassuolo Italy
| | - M. Corazza
- Department of Medical Sciences Section of Dermatology University of Ferrara Ferrara Italy
| | - G. Pellacani
- Department of Surgical, Medical, Dental & Morphological Sciences with Interest Transplant Oncological & Regenerative Medicine Dermatology Unit University of Modena & Reggio Emilia Modena Italy
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Abstract
Despite our understanding that the microvasculature plays a multifaceted role in the development and progression of various conditions, we know little about the extent of this involvement. A need exists for non-invasive, clinically meaningful imaging modalities capable of elucidating microvascular information to aid in our understanding of disease, and to aid in the diagnosis/monitoring of disease for more patient-specific care. In this review article, a number of imaging techniques are summarized that have been utilized to investigate the microvasculature of skin, along with their advantages, disadvantages and future perspectives in preclinical and clinical settings. These techniques include dermoscopy, capillaroscopy, Doppler sonography, laser Doppler flowmetry (LDF) and perfusion imaging, laser speckle contrast imaging (LSCI), optical coherence tomography (OCT), including its Doppler and dynamic variant and the more recently developed OCT angiography (OCTA), photoacoustic imaging, and spatial frequency domain imaging (SFDI). Attention is largely, but not exclusively, placed on optical imaging modalities that use intrinsic optical signals to contrast the microvasculature. We conclude that whilst each imaging modality has been successful in filling a particular niche, there is no one, all-encompassing modality without inherent flaws. Therefore, the future of cutaneous microvascular imaging may lie in utilizing a multi-modal approach that will counter the disadvantages of individual systems to synergistically augment our imaging capabilities.
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Affiliation(s)
- Anthony J Deegan
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle, WA 98195, United States of America
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22
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Andleeb F, Ullah H. Optical coherence tomography in early detection of malignancies. MINERVA BIOTECNOL 2018. [DOI: 10.23736/s1120-4826.18.02466-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Wang L, Li Y, Li Y, Li K. Improved speckle contrast optical coherence tomography angiography. Am J Transl Res 2018; 10:3025-3035. [PMID: 30416648 PMCID: PMC6220225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 09/22/2018] [Indexed: 06/09/2023]
Abstract
Optical coherence tomography (OCT) is becoming a clinically useful and important imaging technique due to its ability to provide high-resolution structural imaging in vivo. Optical coherence tomography angiography (OCTA) can visualize vasculature imaging of biological tissues. With the advent of Fourier-domain OCT, numerous OCTA techniques have been developed to detect the microvasculature in vivo. The macular region of the fundus is separated into retinal and choroid regions by segmentation algorithm in the data processing, a false blood flow signal is generated due to bulk motion when vasculature imaging was segmented in the retinal regions. However, the most recent OCT angiographic approaches are sensitive to bulk motion noise. To overcome this limitation, we proposed an improved speckle contrast optical coherence tomography angiography (ISC-OCTA) algorithm to image vasculature network in vivo. The improved speckle contrast image was acquired by the improved speckle contrast algorithm for N consecutive frames of the same location, and the vasculature of the tissue was generated by masking the averaged image with the improved speckle contrast image. ISC-OCTA was tested on in vivo images of a phantom mouse ear and a human macula. Compared to the recently reported algorithms, we found that ISC-OCTA can distinguish the dynamic information of blood flow from static tissue and visualize capillary vessels. Especially when the segmentation data generates false information, the ISC-OCTA algorithm has a significant effect on the suppression of the line noise. ISC-OCTA can provide clear visualization of vessels as other algorithms and may be useful in the diagnosis of ophthalmic diseases.
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Affiliation(s)
- Liwei Wang
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin 300192, China
| | - Yuejie Li
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin 300192, China
| | - Yilu Li
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin 300192, China
| | - Kaining Li
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin 300192, China
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Mogensen M, Bojesen S, Israelsen NM, Maria M, Jensen M, Podoleanu A, Bang O, Haedersdal M. Two optical coherence tomography systems detect topical gold nanoshells in hair follicles, sweat ducts and measure epidermis. JOURNAL OF BIOPHOTONICS 2018; 11:e201700348. [PMID: 29611306 DOI: 10.1002/jbio.201700348] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 04/02/2018] [Indexed: 06/08/2023]
Abstract
Optical coherence tomography (OCT) is an established imaging technology for in vivo skin investigation. Topical application of gold nanoshells (GNS) provides contrast enhancement in OCT by generating a strong hyperreflective signal from hair follicles and sweat glands, which are the natural skin openings. This study explores the utility of 150 nm diameter GNS as contrast agent for OCT imaging. GNS was massaged into skin and examined in four skin areas of 11 healthy volunteers. A commercial OCT system and a prototype with 3 μm resolution (UHR-OCT) were employed to detect potential benefits of increased resolution and variability in intensity generated by the GNS. In both OCT-systems GNS enhanced contrast from hair follicles and sweat ducts. Highest average penetration depth of GNS was in armpit 0.64 mm ± SD 0.17, maximum penetration depth was 1.20 mm in hair follicles and 15 to 40 μm in sweat ducts. Pixel intensity generated from GNS in hair follicles was significantly higher in UHR-OCT images (P = .002) and epidermal thickness significantly lower 0.14 vs 0.16 mm (P = .027). This study suggests that GNSs are interesting candidates for increasing sensitivity in OCT diagnosis of hair and sweat gland disorders and demonstrates that choice of OCT systems influences results.
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Affiliation(s)
- Mette Mogensen
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Sophie Bojesen
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Niels M Israelsen
- DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Michael Maria
- DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Mikkel Jensen
- DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Adrian Podoleanu
- School of Physical Sciences, Ingram Building, University of Kent, Canterbury, UK
| | - Ole Bang
- DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Kongens Lyngby, Denmark
- NKT Photonics A/S, Birkerød, Denmark
| | - Merete Haedersdal
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
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Fuchs CSK, Andersen AJB, Ardigo M, Philipsen PA, Haedersdal M, Mogensen M. Acne vulgaris severity graded by in vivo reflectance confocal microscopy and optical coherence tomography. Lasers Surg Med 2018; 51:104-113. [DOI: 10.1002/lsm.23008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2018] [Indexed: 12/27/2022]
Affiliation(s)
- Christine S. K. Fuchs
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen Denmark
| | - Amanda J. B. Andersen
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen Denmark
| | - Marco Ardigo
- Clinical Dermatology; IFO-San Gallicano Dermatological Institute-IRCCS; Rome Italy
| | - Peter A. Philipsen
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen Denmark
| | - Merete Haedersdal
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen Denmark
| | - Mette Mogensen
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen Denmark
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Men S, Wong JM, Welch EJ, Xu J, Song S, Deegan AJ, Ravichander A, Casavant B, Berthier E, Wang RK. OCT-based angiography of human dermal microvascular reactions to local stimuli: Implications for increasing capillary blood collection volumes. Lasers Surg Med 2018; 50:908-916. [PMID: 29799134 DOI: 10.1002/lsm.22944] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2018] [Indexed: 12/22/2022]
Abstract
OBJECTIVES To measure and compare microvascular responses within the skin of the upper arm to local stimuli, such as heating or rubbing, through the use of optical coherence tomography angiography (OCTA), and to investigate its impact on blood volume collection. MATERIALS AND METHODS With the use of heat packs or rubbing, local stimulation was applied to the skin of either the left or right upper arm. Data from the stimulated sites were obtained using OCTA comparing pre- and post-stimulation microvascular parameters, such as vessel density, mean vessel diameter, and mean avascular pore size. Additionally, blood was collected using a newly designed collection device and volume was recorded to evaluate the effect of the skin stimulation. RESULTS Nineteen subjects were recruited for local stimulation study (including rubbing and heating) and 21 subjects for blood drawn study. Of these subjects, 14 agreed to participate in both studies. OCTA was successful in monitoring and measuring minute changes in the microvasculature of the stimulated skin. Compared to baseline, significant changes after local heating and rubbing were respectively found in vessel density (16% [P = 0.0004] and 33% [P < 0.0001] increase), mean vessel diameter (14% and 11% increase) and mean avascular pore size (5% [P = 0.0068] and 8% [P = 0.0005] decrease) after stimulations. A gradual recovery was recorded for each parameter, with no difference being measured after 30 minutes. Blood collection volumes significantly increased after stimulations of heating (48% increase; P = 0.049) and rubbing (78% increase; P = 0.048). Significant correlations were found between blood volume and microvascular parameters except mean avascular pore size under the heating condition. CONCLUSIONS OCTA can provide important information regarding microvascular adaptations to local stimuli. With that, both heating and rubbing of the skin have positive effects on blood collection capacity, with rubbing having the most significant effect. Lasers Surg. Med. 50:908-916, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Shaojie Men
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle 98195, Washington
| | - Jennifer Manyu Wong
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle 98195, Washington
| | - Emily J Welch
- Tasso, Inc., 1631 15th Ave. W., Suite 105, Seattle 98119, Washington
| | - Jingjiang Xu
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle 98195, Washington
| | - Shaozhen Song
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle 98195, Washington
| | - Anthony J Deegan
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle 98195, Washington
| | | | - Benjamin Casavant
- Tasso, Inc., 1631 15th Ave. W., Suite 105, Seattle 98119, Washington
| | - Erwin Berthier
- Tasso, Inc., 1631 15th Ave. W., Suite 105, Seattle 98119, Washington
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, 3720 15th Ave. NE., Seattle 98195, Washington
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Andersen AJB, Fuchs C, Ardigo M, Haedersdal M, Mogensen M. In vivo characterization of pustules in Malassezia Folliculitis by reflectance confocal microscopy and optical coherence tomography. A case series study. Skin Res Technol 2018; 24:535-541. [PMID: 29484711 DOI: 10.1111/srt.12463] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/28/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND OBJECTIVE Malassezia Folliculitis (MaF) is an inflammatory condition of hair follicles caused by Malassezia yeast. Optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) are imaging technologies enabling in vivo visualization of superficial skin layers. This study explores morphology of pustules in MaF imaged by OCT and RCM. METHODS Patients with microscopically verified MaF were included in this case series. Morphology was evaluated qualitatively with RCM and OCT, focusing on shape, border and content of selected pustules. RESULTS Nine patients with MaF were included. Clinically, six patients presented monomorphic MaF with multiple superficial pustules, while three patients showed more polymorph MaF appearance. In total 13 pustules were investigated by RCM and OCT. In RCM images, pustules varied from having a well-defined border with homogenous content to ill-defined borders with heterogeneous content. A distinct black halo was occasionally observed around pustules as were dilated vessels. In OCT images, pustules appeared polymorphic, showing both well- and ill-defined structures with oval or irregular shape and more or less homogenous content. Malassezia fungi were not discernible by either RCM or OCT. Specific morphological image features in RCM and OCT did not reflect different clinical manifestations of MaF. CONCLUSION RCM and OCT images identify morphological aspects of MaF pustules, and confirm that MaF is a folliculitis with clinical as well as morphological variance.
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Affiliation(s)
- A J B Andersen
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - C Fuchs
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - M Ardigo
- Clinical Dermatology, IFO-San Gallicano Dermatological Institute, Rome, Italy
| | - M Haedersdal
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - M Mogensen
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
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Manfredini M, Greco M, Farnetani F, Ciardo S, De Carvalho N, Mandel VD, Starace M, Pellacani G. Acne: morphologic and vascular study of lesions and surrounding skin by means of optical coherence tomography. J Eur Acad Dermatol Venereol 2017; 31:1541-1546. [PMID: 28556980 DOI: 10.1111/jdv.14369] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 04/28/2017] [Indexed: 11/29/2022]
Abstract
BACKGROUND Acne vulgaris is a disease of the pilosebaceous unit, characterized by hyper-keratinization process, comedos formation and inflammatory reactions. OBJECTIVE The definition of the morphology and the vascularization of acne lesions by means of dynamic optical coherence tomography (D-OCT), to non-invasively define the alterations occurring during the acne development and patient therapeutic management. METHODS A set of standardized clinical pictures and D-OCT images were acquired from 114 acne lesions of 31 volunteers, presenting mild to moderate acne and evaluated by experts. Fifteen patients treated with oral antibiotics were followed during time at 0, 20, 40, and 60 days. RESULTS Optical coherence tomography enabled to identify vascular and morphological aspects characterizing different types of acne lesions. Oral antibiotic treatment improved the morphologic features and decreased the digitally reconstructed vascular signal during time. CONCLUSION The characterization of acne lesions and the identification of vascular pattern in acne lesions through D-OCT, corresponding to blood vessel dilation and inflammatory associated hyper-vascularization, may have important clinical consequences in the assessment of acne severity, therapeutic decisions and treatment efficacy monitoring.
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Affiliation(s)
- M Manfredini
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - M Greco
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - F Farnetani
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - S Ciardo
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - N De Carvalho
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - V D Mandel
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - M Starace
- Division of Dermatology, Department of Specialized, Clinical, and Experimental Medicine, University of Bologna, Bologna, Italy
| | - G Pellacani
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
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Baran U, Swanson E, Sanders JE, Wang RK. OCT-based microangiography for reactive hyperaemia assessment within residual limb skin of people with lower limb loss. Skin Res Technol 2017; 24:152-155. [PMID: 28544155 DOI: 10.1111/srt.12383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2017] [Indexed: 11/27/2022]
Affiliation(s)
- U Baran
- Department of Bioengineering, University of Washington, Seattle, WA, USA.,Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - E Swanson
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - J E Sanders
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - R K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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Men SJ, Chen CL, Wei W, Lai TY, Song SZ, Wang RK. Repeatability of vessel density measurement in human skin by OCT-based microangiography. Skin Res Technol 2017; 23:607-612. [PMID: 28514014 DOI: 10.1111/srt.12379] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2017] [Indexed: 12/26/2022]
Abstract
PURPOSE To investigate the repeatability of vessel density measurement at human arm skin in healthy subjects with OCT-based microangiography (OMAG). METHODS Four locations including volar wrist, volar forearm, shoulder, and volar upper arm were scanned using an optimized swept source OCT system, working at center wavelength of 1300 nm and A-line rate of 100 kHz. Three scans were acquired at each location at the same visit. Vascular images of papillary dermis, reticular dermis, and the whole dermis layer were generated with OMAG processing and automatic segmentation algorithms. The vessel density (VD) of each layer was calculated based on vascular images, and the repeatability of the VD at the same physiological location was thereafter assessed. RESULTS Fifteen healthy volunteers were included. High repeatability of VD was found for wrist, forearm, shoulder, and upper arm (coefficient of variation (CV)=2.4, 2.7, 2.7, 2.0, and intraclass correlation coefficient (ICC)=0.906, 0.854, 0.943, 0.916 respectively). The VD measurements showed no significant difference between the four locations in any of the three layers, ie papillary layer (P=.1063), reticular layer (P=.3371), and whole dermis layer (P=.3233). CONCLUSION Quantification of VD by using OCT/OMAG is repeatable when imaging skin tissue beds in healthy individuals.
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Affiliation(s)
- S J Men
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - C-L Chen
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - W Wei
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - T-Y Lai
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - S Z Song
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - R K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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Englhard AS, Betz T, Volgger V, Lankenau E, Ledderose GJ, Stepp H, Homann C, Betz CS. Intraoperative assessment of laryngeal pathologies with optical coherence tomography integrated into a surgical microscope. Lasers Surg Med 2017; 49:490-497. [PMID: 28231390 DOI: 10.1002/lsm.22632] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/28/2016] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Endoscopic examination followed by tissue biopsy is the gold standard in the evaluation of lesions of the upper aerodigestive tract. However, it can be difficult to distinguish between healthy mucosa, dysplasia, and invasive carcinoma. Optical coherence tomography (OCT) is a non-invasive technique which acquires high-resolution, cross-sectional images of tissue in vivo. Integrated into a surgical microscope, it allows the intraoperative evaluation of lesions simultaneously with microscopic visualization. STUDY DESIGN In a prospective case series, we evaluated the use of OCT integrated into a surgical microscope during microlaryngoscopy to help differentiating various laryngeal pathologies. METHODS 33 patients with laryngeal pathologies were examined with an OCT- microscope (OPMedT iOCT-camera, HS Hi-R 1000G-microscope, Haag-Streit Surgical GmbH, Wedel, Germany) during microlaryngoscopy. The suspected intraoperative diagnoses were compared to the histopathological reports of subsequent tissue biopsies. RESULTS Hands-free non-contact OCT revealed high-resolution images of the larynx with a varying penetration depth of up to 1.2 mm and an average of 0.6 mm. Picture quality was variable. OCT showed disorders of horizontal tissue layering in dysplasias with a disruption of the basement membrane in carcinomas. When comparing the suspected diagnosis during OCT-supported microlaryngoscopy with histology, 79% of the laryngeal lesions could be correctly identified. Premalignant lesions were difficult to diagnose and falsely classified as carcinoma. CONCLUSION OCT integrated into a surgical microscope seems to be a promising adjunct tool to discriminate pathologies of the upper aerodigestive tract intraoperatively. However, picture quality and penetration depth were variable. Although premalignant lesions were difficult to diagnose, the system proved overall helpful for the intraoperative discrimination of benign and malignant tumors. Further studies will be necessary to define its value in the future. Lasers Surg. Med. 49:490-497, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Anna S Englhard
- Department of Otorhinolaryngology-Head and Neck Surgery, Klinikum der Universität München, Marchioninistr. 15, 81377 Munich, Germany
| | - Tom Betz
- Department of Otorhinolaryngology-Head and Neck Surgery, Klinikum der Universität München, Marchioninistr. 15, 81377 Munich, Germany
| | - Veronika Volgger
- Department of Otorhinolaryngology-Head and Neck Surgery, Klinikum der Universität München, Marchioninistr. 15, 81377 Munich, Germany
| | - Eva Lankenau
- OptoMedical Technologies GmbH, Maria-Goeppert-Strasse 9, 23562 Lübeck, Germany
| | - Georg J Ledderose
- Department of Otorhinolaryngology-Head and Neck Surgery, Klinikum der Universität München, Marchioninistr. 15, 81377 Munich, Germany
| | - Herbert Stepp
- Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Feodor-Lynen-Str.19, 81377 Munich, Germany
| | - Christian Homann
- Laser-Forschungslabor, LIFE-Zentrum, Klinikum der Universität München, Feodor-Lynen-Str.19, 81377 Munich, Germany
| | - Christian S Betz
- Department of Otorhinolaryngology-Head and Neck Surgery, Klinikum der Universität München, Marchioninistr. 15, 81377 Munich, Germany
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Chen CL, Wang RK. Optical coherence tomography based angiography [Invited]. BIOMEDICAL OPTICS EXPRESS 2017; 8:1056-1082. [PMID: 28271003 PMCID: PMC5330554 DOI: 10.1364/boe.8.001056] [Citation(s) in RCA: 270] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/16/2017] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT)-based angiography (OCTA) provides in vivo, three-dimensional vascular information by the use of flowing red blood cells as intrinsic contrast agents, enabling the visualization of functional vessel networks within microcirculatory tissue beds non-invasively, without a need of dye injection. Because of these attributes, OCTA has been rapidly translated to clinical ophthalmology within a short period of time in the development. Various OCTA algorithms have been developed to detect the functional micro-vasculatures in vivo by utilizing different components of OCT signals, including phase-signal-based OCTA, intensity-signal-based OCTA and complex-signal-based OCTA. All these algorithms have shown, in one way or another, their clinical values in revealing micro-vasculatures in biological tissues in vivo, identifying abnormal vascular networks or vessel impairment zones in retinal and skin pathologies, detecting vessel patterns and angiogenesis in eyes with age-related macular degeneration and in skin and brain with tumors, and monitoring responses to hypoxia in the brain tissue. The purpose of this paper is to provide a technical oriented overview of the OCTA developments and their potential pre-clinical and clinical applications, and to shed some lights on its future perspectives. Because of its clinical translation to ophthalmology, this review intentionally places a slightly more weight on ophthalmic OCT angiography.
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Affiliation(s)
- Chieh-Li Chen
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195, USA
- Department of Ophthalmology, University of Washington, 325 9th Ave, Seattle, WA 98104, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA 98195, USA
- Department of Ophthalmology, University of Washington, 325 9th Ave, Seattle, WA 98104, USA
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Liu M, Chen Z, Zabihian B, Sinz C, Zhang E, Beard PC, Ginner L, Hoover E, Minneman MP, Leitgeb RA, Kittler H, Drexler W. Combined multi-modal photoacoustic tomography, optical coherence tomography (OCT) and OCT angiography system with an articulated probe for in vivo human skin structure and vasculature imaging. BIOMEDICAL OPTICS EXPRESS 2016; 7:3390-3402. [PMID: 27699106 PMCID: PMC5030018 DOI: 10.1364/boe.7.003390] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 07/28/2016] [Accepted: 08/09/2016] [Indexed: 05/05/2023]
Abstract
Cutaneous blood flow accounts for approximately 5% of cardiac output in human and plays a key role in a number of a physiological and pathological processes. We show for the first time a multi-modal photoacoustic tomography (PAT), optical coherence tomography (OCT) and OCT angiography system with an articulated probe to extract human cutaneous vasculature in vivo in various skin regions. OCT angiography supplements the microvasculature which PAT alone is unable to provide. Co-registered volumes for vessel network is further embedded in the morphologic image provided by OCT. This multi-modal system is therefore demonstrated as a valuable tool for comprehensive non-invasive human skin vasculature and morphology imaging in vivo.
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Affiliation(s)
- Mengyang Liu
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, AKH 4L, Vienna, 1090, Austria
| | - Zhe Chen
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, AKH 4L, Vienna, 1090, Austria
| | - Behrooz Zabihian
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, AKH 4L, Vienna, 1090, Austria
| | - Christoph Sinz
- Department of Dermatology, Medical University of Vienna, Währinger Gürtel 18-20, AKH 7J, Vienna, 1090, Austria
| | - Edward Zhang
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
| | - Paul C. Beard
- Department of Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, UK
| | - Laurin Ginner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, AKH 4L, Vienna, 1090, Austria
| | - Erich Hoover
- INSIGHT Photonic Solutions, Inc., 300 S. Public Road, Lafayette, CO, 80026, USA
| | - Micheal P. Minneman
- INSIGHT Photonic Solutions, Inc., 300 S. Public Road, Lafayette, CO, 80026, USA
| | - Rainer A. Leitgeb
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, AKH 4L, Vienna, 1090, Austria
| | - Harald Kittler
- Department of Dermatology, Medical University of Vienna, Währinger Gürtel 18-20, AKH 7J, Vienna, 1090, Austria
| | - Wolfgang Drexler
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, AKH 4L, Vienna, 1090, Austria
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Lal C, Leahy MJ. An Updated Review of Methods and Advancements in Microvascular Blood Flow Imaging. Microcirculation 2016; 23:345-63. [DOI: 10.1111/micc.12284] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 04/17/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Cerine Lal
- Department of Applied Physics; Tissue Optics and Microcirculation Imaging; National University of Ireland; Galway Ireland
| | - Martin J Leahy
- Department of Applied Physics; Tissue Optics and Microcirculation Imaging; National University of Ireland; Galway Ireland
- Royal College of Surgeons in Ireland; Dublin Ireland
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Baran U, Zhu W, Choi WJ, Omori M, Zhang W, Alkayed NJ, Wang RK. Automated segmentation and enhancement of optical coherence tomography-acquired images of rodent brain. J Neurosci Methods 2016; 270:132-137. [PMID: 27328369 DOI: 10.1016/j.jneumeth.2016.06.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/09/2016] [Accepted: 06/15/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND Optical coherence tomography (OCT) is a non-invasive optical imaging method that has proven useful in various fields such as ophthalmology, dermatology and neuroscience. In ophthalmology, significant progress has been made in retinal layer segmentation and enhancement of OCT images. There are also segmentation algorithms to separate epidermal and dermal layers in OCT-acquired images of human skin. NEW METHOD We describe simple image processing methods that allow automatic segmentation and enhancement of OCT images of rodent brain. RESULTS We demonstrate the effectiveness of the proposed methods for OCT-based microangiography (OMAG) and tissue injury mapping (TIM) of mouse cerebral cortex. The results show significant improvement in image contrast, delineation of tissue injury, allowing visualization of different layers of capillary beds. COMPARISON WITH EXISTING METHODS Previously reported methods for other applications are yet to be used in neuroscience due to the complexity of tissue anatomy, unique physiology and technical challenges. CONCLUSIONS OCT is a promising tool that provides high resolution in vivo microvascular and structural images of rodent brain. By automatically segmenting and enhancing OCT images, structural and microvascular changes in mouse cerebral cortex after stroke can be monitored in vivo with high contrast.
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Affiliation(s)
- Utku Baran
- Dept. of Bioengineering, University of Washington, 3720 15th Ave. NE, Seattle, WA 98195, USA; Dept. of Electrical Engineering, University of Washington, 185 Stevens Way, Seattle, WA 98195, USA
| | - Wenbin Zhu
- Dept. of Anesthesiology and Perioperative Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
| | - Woo June Choi
- Dept. of Bioengineering, University of Washington, 3720 15th Ave. NE, Seattle, WA 98195, USA
| | - Michael Omori
- Dept. of Electrical Engineering, University of Washington, 185 Stevens Way, Seattle, WA 98195, USA
| | - Wenri Zhang
- Dept. of Anesthesiology and Perioperative Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
| | - Nabil J Alkayed
- Dept. of Anesthesiology and Perioperative Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
| | - Ruikang K Wang
- Dept. of Bioengineering, University of Washington, 3720 15th Ave. NE, Seattle, WA 98195, USA.
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Baran U, Choi WJ, Wang RK. Potential use of OCT-based microangiography in clinical dermatology. Skin Res Technol 2016; 22:238-246. [PMID: 26335451 PMCID: PMC4777681 DOI: 10.1111/srt.12255] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2015] [Indexed: 11/26/2022]
Abstract
BACKGROUND Optical coherence tomography (OCT) is a revolutionary imaging technique used commonly in ophthalmology, and on the way to become clinically viable alternative in dermatology due to its capability of acquiring histopathology level details of in vivo tissue, non-invasively. In this study, we demonstrate the capabilities of OCT-based microangiography in detecting high resolution, three-dimensional structural, and microvascular features of in vivo human skin with various conditions. METHODS A swept-source OCT system that operates on a central wavelength of 1310 nm with an A-line rate of 100 kHz is used in this study. We apply optical microangiography (OMAG) technique to visualize the structural and microvascular changes in tissue. RESULTS OMAG images provide detailed visualization of functional microvasculature of healthy human skin from cheek and forehead areas, abnormal skin conditions from face, chest and belly. Moreover, OMAG is capable of monitoring the progress of wound healing on human skin from arm, delivering unprecedented detail of microstructural and microvascular information during longitudinal wound healing process. CONCLUSION The presented results promise the clinical use of OCT angiography, aiming to treat prevalent cutaneous diseases, by detecting blood perfusion, and structural changes within human skin, in vivo.
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Affiliation(s)
- Utku Baran
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Department of Electrical Engineering, University of Washington, Seattle, WA, USA
| | - Woo June Choi
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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OCT-based label-free in vivo lymphangiography within human skin and areola. Sci Rep 2016; 6:21122. [PMID: 26892830 PMCID: PMC4759696 DOI: 10.1038/srep21122] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 01/18/2016] [Indexed: 01/29/2023] Open
Abstract
Due to the limitations of current imaging techniques, visualization of lymphatic capillaries within tissue in vivo has been challenging. Here, we present a label-free high resolution optical coherence tomography (OCT) based lymphangiography (OLAG) within human skin in vivo. OLAG enables rapid (~seconds) mapping of lymphatic networks, along with blood vessel networks, over 8 mm x 8 mm of human skin and 5 mm x 5 mm of human areola. Moreover, lymphatic system’s response to inflammation within human skin is monitored throughout an acne lesion development over 7 days. The demonstrated results promise OLAG as a revolutionary tool in the clinical research and treatment of patients with pathologic conditions such as cancer, diabetes, and autoimmune diseases.
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Zhang A, Zhang Q, Chen CL, Wang RK. Methods and algorithms for optical coherence tomography-based angiography: a review and comparison. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:100901. [PMID: 26473588 PMCID: PMC4881033 DOI: 10.1117/1.jbo.20.10.100901] [Citation(s) in RCA: 198] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/28/2015] [Indexed: 05/18/2023]
Abstract
Optical coherence tomography (OCT)-based angiography is increasingly becoming a clinically useful and important imaging technique due to its ability to provide volumetric microvascular networks innervating tissue beds in vivo without a need for exogenous contrast agent. Numerous OCT angiography algorithms have recently been proposed for the purpose of contrasting microvascular networks. A general literature review is provided on the recent progress of OCT angiography methods and algorithms. The basic physics and mathematics behind each method together with its contrast mechanism are described. Potential directions for future technical development of OCT based angiography is then briefly discussed. Finally, by the use of clinical data captured from normal and pathological subjects, the imaging performance of vascular networks delivered by the most recently reported algorithms is evaluated and compared, including optical microangiography, speckle variance,phase variance, split-spectrum amplitude decorrelation angiography, and correlation mapping. It is found that the method that utilizes complex OCT signal to contrast retinal blood flow delivers the best performance among all the algorithms in terms of image contrast and vessel connectivity. The purpose of this review is to help readers understand and select appropriate OCT angiography algorithm for use in specific applications.
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Affiliation(s)
- Anqi Zhang
- University of Washington, Department of Bioengineering, Seattle, Washington 98195, United States
| | - Qinqin Zhang
- University of Washington, Department of Bioengineering, Seattle, Washington 98195, United States
| | - Chieh-Li Chen
- University of Washington, Department of Bioengineering, Seattle, Washington 98195, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, Seattle, Washington 98195, United States
- Address all correspondence to: Ruikang K. Wang, E-mail:
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Qin W, Baran U, Wang R. Lymphatic response to depilation-induced inflammation in mouse ear assessed with label-free optical lymphangiography. Lasers Surg Med 2015. [PMID: 26224650 DOI: 10.1002/lsm.22387] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVES Optical microangiography (OMAG) is a noninvasive technique capable of imaging 3D microvasculature. OMAG-based optical lymphangiography has been developed for 3D visualization of lymphatic vessels without the need for exogenous contrast agents. In this study, we utilize the optical lymphangiography to investigate dynamic changes in lymphatic response within skin tissue to depilation-induced inflammation by using mouse ear as a simple tissue model. MATERIALS AND METHODS A spectral-domain optical coherence tomography (OCT) system is used in this study to acquire volumetric images of mouse ear. The system operates under the ultrahigh-sensitive OMAG scanning protocol with five repetitions for each B frame. An improved adaptive-threshold-based method is proposed to segment lymphatic vessels from OCT microstructure images. Depilation is achieved by placing hair removal lotion on mouse ear pinna for 5 minutes. Three acquisitions are made before depilation, 3-minute and 30-minute post-depilation, respectively. RESULTS Right after the application of depilation lotion on the skin, we observe that the blind-ended sacs of initial lymphatics are mainly visible in a specific area of the normal tissue. At 5 minutes, more collecting lymphatic vessels start to form, evidenced by their valve structure that only exists in collecting lymphatic vessels. The lymphangiogenesis is almost completed within 8 minutes in the inflammatory tissue. CONCLUSIONS Our experimental results demonstrate that the OMAG-based optical lymphangiography has great potential to improve the understanding of lymphatic system in response to various physiological conditions, thus would benefit the development of effective therapeutics.
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Affiliation(s)
- Wan Qin
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, Washington 98195-5061
| | - Utku Baran
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, Washington 98195-5061
| | - Ruikang Wang
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, Washington 98195-5061.,Department of Ophthalmology, University of Washington, 3720 15th Ave NE, Seattle, Washington 98195-5061
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Baran U, Li Y, Wang RK. In vivo tissue injury mapping using optical coherence tomography based methods. APPLIED OPTICS 2015; 54:6448-53. [PMID: 26367827 PMCID: PMC4570269 DOI: 10.1364/ao.54.006448] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
An injury causes changes in the optical attenuation coefficient (OAC) of a light beam traveling inside a tissue. We report a method called tissue injury mapping (TIM), which utilizes a noninvasive in vivo optical coherence tomography approach to generate an OAC and microvascular map of the injured tissue. Using TIM, the infarct region development in a mouse cerebral cortex during a stroke is visualized. Moreover, we demonstrate the changes in human facial skin structure and microvasculature during an acne lesion development from initiation to scarring. The results indicate that TIM may be used to aid in the characterization and the treatment of various diseases by enabling a high-resolution detection of tissue structural and microvascular changes.
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Affiliation(s)
- Utku Baran
- Dept. of Bioengineering, University of Washington, 3720 15th Ave. NE, Seattle WA 98195, USA
- Dept. of Electrical Engineering, University of Washington, 185 Stevens Way, Seattle WA 98195, USA
| | - Yuandong Li
- Dept. of Bioengineering, University of Washington, 3720 15th Ave. NE, Seattle WA 98195, USA
| | - Ruikang K. Wang
- Dept. of Bioengineering, University of Washington, 3720 15th Ave. NE, Seattle WA 98195, USA
- Corresponding author:
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Baran U, Li Y, Wang RK. Vasodynamics of pial and penetrating arterioles in relation to arteriolo-arteriolar anastomosis after focal stroke. NEUROPHOTONICS 2015; 2:025006. [PMID: 26158010 PMCID: PMC4478965 DOI: 10.1117/1.nph.2.2.025006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/18/2015] [Indexed: 05/18/2023]
Abstract
Changes in blood perfusion in highly interconnected pial arterioles provide important insights about the vascular response to ischemia within brain. The functional role of arteriolo-arteriolar anastomosis (AAA) in regulating blood perfusion through penetrating arterioles is yet to be discovered. We apply a label-free optical microangiography (OMAG) technique to evaluate the changes in vessel lumen diameter and red blood cell velocity among a large number of pial and penetrating arterioles within AAA abundant region overlaying the penumbra in the parietal cortex after a middle cerebral artery occlusion (MCAO). In comparison with two-photon microscopy, the OMAG technique makes it possible to image a large number of vessels in a short period of time without administering exogenous contrast agents during a time-constrained MCAO experiment. We compare vasodynamics in penetrating arterioles at various locations. The results show that the MCA connected penetrating arterioles close to a strong AAA dilate, while those belonging to a region away from AAAs constrict in various degrees. These results suggest AAAs play a major role in supporting the active dilation of the penetrating arterioles, thus compensating a significant amount of blood to the ischemic region, whereas the poor blood perfusion occurs at the regions away from AAA connections, leading to ischemia.
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Affiliation(s)
- Utku Baran
- University of Washington, Department of Bioengineering, 3720 NE 15th Avenue, Seattle, Washington 98195, United States
- University of Washington, Department of Electrical Engineering, 185 Stevens Way, Seattle, Washington 98195, United States
| | - Yuandong Li
- University of Washington, Department of Bioengineering, 3720 NE 15th Avenue, Seattle, Washington 98195, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, 3720 NE 15th Avenue, Seattle, Washington 98195, United States
- Address all correspondence to: Ruikang K. Wang, E-mail:
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