Angiographic optical coherence tomography imaging of hemangiomas and port wine birthmarks

Optical coherence tomography-measured blood vessel characteristics of port-wine birthmarks by depth: A cross-sectional study

BACKGROUND

Port-Wine Birthmarks (PWB) are congenital capillary malformations requiring multiple treatments. Optical coherence tomography (OCT), a noninvasive imaging technique, characterizes vessels in cutaneous vascular lesions, including PWBs.

OBJECTIVE

To assess variability in blood vessel characteristics within and between individual PWBs.

METHODS

OCT was used to measure blood vessel density (%) and modal vessel diameter (micrometers) at increments of 0.05 mm from the skin surface to a depth of 0.50 mm at several adjacent spots of single PWBs in this cross-sectional study. Average ratios of vessel density and diameter in affected to control skin were obtained for each PWB by averaging data for all spots within a lesion. Statistical analysis was performed with a linear mixed effects model using SPSS software (IBM Corporation).

RESULTS

There was great variability in vessel density and diameter within and between PWBs. Depths where average ratios of vessel density were consistently greater in affected to control skin were shallow, between 0.15 mm and 0.2 mm deep from the skin surface.

LIMITATIONS

Small sample size and device's inability to measure diameters smaller than 20 micrometers.

CONCLUSION

There is variability in vessel density and diameter within and between PWBs. Individualized treatment planning guided by OCT mapping should be studied further.

Mapping port wine stain in vivo by optical coherence tomography angiography and multi-metric characterization

Port wine stain (PWS) is a congenital cutaneous capillary malformation composed of ecstatic vessels, while the microstructure of these vessels remains largely unknown. Optical coherence tomography angiography (OCTA) serves as a non-invasive, label-free and high-resolution tool to visualize the 3D tissue microvasculature. However, even as the 3D vessel images of PWS become readily accessible, quantitative analysis algorithms for their organization have mainly remained limited to analysis of 2D images. Especially, 3D orientations of vasculature in PWS have not yet been resolved at a voxel-wise basis. In this study, we employed the inverse signal-to-noise ratio (iSNR)-decorrelation (D) OCTA (ID-OCTA) to acquire 3D blood vessel images in vivo from PWS patients, and used the mean-subtraction method for de-shadowing to correct the tail artifacts. We developed algorithms which mapped blood vessels in spatial-angular hyperspace in a 3D context, and obtained orientation-derived metrics including directional variance and waviness for the characterization of vessel alignment and crimping level, respectively. Combining with thickness and local density measures, our method served as a multi-parametric analysis platform which covered a variety of morphological and organizational characteristics at a voxel-wise basis. We found that blood vessels were thicker, denser and less aligned in lesion skin in contrast to normal skin (symmetrical parts of skin lesions on the cheek), and complementary insights from these metrics led to a classification accuracy of ∼90% in identifying PWS. An improvement in sensitivity of 3D analysis was validated over 2D analysis. Our imaging and analysis system provides a clear picture of the microstructure of blood vessels within PWS tissues, which leads to a better understanding of this capillary malformation disease and facilitates improvements in diagnosis and treatment of PWS.

Histological analysis of different types of port-wine stains to guide clinical decision making: A retrospective study

Background and objectives Port-wine stains are defined as congenital benign vascular lesions. The treatment of port-wine stains remains a challenge, worldwide. This study aimed to analyze the histological characteristics in different types of port-wine stains and provide guidance for clinical decision-making. Methods and materials Biopsies were from the hospital from 2015 to 2021. H&E staining, Immunofluorescence staining, Masson's trichrome staining and Weigert staining were performed on the tissues. Results A total of 35 port-wine stains patients were included in the study of four distinct types, namely red port-wine stains (11 cases), purple port-wine stains (seven cases), hypertrophic port-wine stains (nine cases) and nodular port-wine stains (eight cases). The mean vessel diameter of the different types was 38.7 ± 5.9 μm, 93.5 ± 9.7 μm, 155.6 ± 21.8 μm and 155.6 ± 29.54 μm, respectively. Mean vessel depth was 396.4 ± 31 μm, 944.2 ± 105.4 μm, 2,971 ± 161.3 μm and 3,594 ± 364.6 μm, respectively. The vessels in red port-wine stains, purple port-wine stains and hypertrophic port-wine stains were mainly composed of capillary and venous malformations, whereas those in nodular port-wine stains were venous or arteriovenous malformations. Limitation The main limitation of the current study was the small number of patients. Conclusion As the disease progresses, vessel diameters become larger, the vessel wall becomes thicker and vessels were found in a greater depth. A treatment plan should be scientifically formulated keeping in mind the histological characteristics of port-wine stains.

Analysis of port-wine birthmark vascular characteristics by location: Utility of optical coherence tomography mapping

INTRODUCTION

Port-wine birthmarks (PWBs) are congenital capillary malformations that can be located on any area of the body. Vascular features include vessel size, depth, and density, which can greatly differ between patients, individual lesions, and even sites within the same lesion. Previous studies have determined that the location of PWB lesions has impacted their clinical response to laser treatment.

OBJECTIVE

We utilized dynamic optical coherence tomography (D-OCT) to measure in vivo vessel diameter, density, and superficial plexus depth in patients of all ages with PWB on various sites of the body. We hypothesized that these vascular characteristics would differ according to body location.

MATERIALS AND METHODS

Patients who had a PWB and presented to clinic at three sites for treatment with the pulsed dye laser (PDL) were enrolled into the study. A D-OCT scanner was utilized for noninvasive, in vivo imaging of PWB lesions. The depth of the top portion of the superficial vascular plexus was estimated as the depth at which the vessel density reaches 50% of the maximum. Vessel diameter and density were calculated by incorporated software algorithm.

RESULTS

A total of 108 patients were enrolled into the study. There was a total of 204 measurements of PWB lesions. Of all patients, 56.5% (n = 61) reported having a previous treatment with PDL. Of all D-OCT scans, 62.3% (n = 127) were located on the head, 14.2% (n = 29) the upper extremities, 8.3% (n = 17) the lower extremities, 7.8% (n = 16) the trunk, and 7.8% (n = 15) the neck. All locations were compared for each vascular characteristic. For superficial plexus depth, lesions on the head were significantly shallower than those on the upper extremities (217 vs. 284 µm; p < 0.001) and lower extremities (217 vs. 309 µm; p < 0.001). For vessel diameter, lesions on the head had significantly larger vessels than those on the upper extremities (100 vs. 72 µm; p = 0.001). For vessel density, lesions on the head had significantly denser vessels than those on the trunk (19% vs. 9.6%; p = 0.039) and upper extremities (19% vs. 9.3%; p < 0.001) CONCLUSIONS: PWB lesions have distinct vascular characteristics, which can be associated with their body location. This includes superficial vascular plexus depth as well as vessel diameter and density.

Optical coherence tomography

During the past decade, noninvasive imaging has emerged as a valuable tool in clinical dermatology and dermatologic research. Optical coherence tomography (OCT) is one such type of noninvasive imaging. OCT uses the principle of interferometry to produce real-time images. A low-power diode laser shines infrared light onto tissues, which reflects back to an optical fiber interferometer. Using time delay and the backscattered light intensity, a two-dimensional image akin to an ultrasound is rendered. We review the history, types, and modalities of OCT, plus the many applications of frequency domain, high definition, and dynamic OCT in practice, including its utility in diagnosis, monitoring, and grading disease severity in a variety of cutaneous conditions.

Quantitative assessment of vascular features in port wine stains through optical coherence tomography angiography

BACKGROUND

Vascular lesions such as port wine stains (PWS) lead to facial and psychological problems, which require careful and precise treatments. The key point of treating PWS is to selectively destroy the abnormal blood vessels. Hence, the in vivo monitoring of targeted vessels is crucial. Optical coherence tomography angiography (OCTA), an emerging label-free imaging tool, facilitates the evaluation of skin structure and vasculature at a high resolution. In this study, we utilised OCTA to capture the structural and vascular morphology in patients with PWS. Moreover, we quantitatively characterised the morphological features of different types of PWS.

METHODS

This observational clinical study was conducted on 3 patients with flat PWS and 3 patients with thickened PWS. The age range was 4-27 years, and all of them had not received any treatment before this study. The OCTA images of the PWS lesions and contralateral skin were compared. Vascular morphology was characterized, and ectatic vessel depth was quantified according to the OCTA images.

RESULTS

The blood vessels of the PWS lesions tend to had larger diameters and higher densities than those in the contralateral normal skin. The vessel diameters of PWS lesions were 73 ± 14 μm, with high heterogeneity ranging from 10 to >150 μm, however, the vessel diameters of normal skin were 28 ± 2 μm, ranging from 10 μm to 60 μm. In terms of different PWS lesions, the thickened type showed a trend of larger vessel diameter and higher density than those of the purplish red type. The ectatic vessels were located at the depth of 216 ± 13 μm in the PWS skin.

CONCLUSIONS

OCTA can facilitate the in vivo three-dimensional visualization of structure and vasculature for PWS lesions. Various quantitative analysis parameters, such as vessel diameter, density, and depth, are typically measured using OCTA. This fact demonstrates the superior capability of OCTA for the precise and comprehensive assessment of PWS lesions.

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

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

Vascular characteristics of port wine birthmarks as measured by dynamic optical coherence tomography

BACKGROUND

Port wine birthmarks (PWBs) are congenital capillary malformations. Vessel characteristics, such as diameter and depth, may impact presentation and outcomes. They can be imaged using dynamic optical coherence tomography, a high-resolution, noninvasive imaging method.

PURPOSE

We conducted a cross-sectional observational study to measure in vivo vascular characteristics as a function of PWB color.

METHODS

Patients undergoing treatment for PWB were recruited from 3 sites. PWBs were classified by color. Dynamic optical coherence tomography images with calculations were obtained.

RESULTS

One hundred eight patients were enrolled. Mean age correlated with PWB color, with birthmarks being lighter in younger patients and darker in older patients (P < .01). Mean superficial plexus depth was significantly shallower in purple PWBs than in pink PWBs. Color was not associated with significant differences in mean superficial vessel density or diameter. Among pink PWBs, each 10-year increase in age was associated with a 10.6-μm increase in superficial plexus depth. Among purple PWBs, each 10-year increase in age was associated with a 16.2-μm reduction in superficial plexus depth. In lesions without prior treatment, vessel density was 12.7% lower in purple PWBs than in pink PWBs.

CONCLUSION

Superficial vessels of purple PWBs were significantly closer to the epidermis than those of pink PWBs, which might impact optimal laser parameters.

Noninvasive diagnostic techniques of port wine stain

Port-wine stain (PWS) is a benign capillary malformation that most commonly occurs in the head and neck. It is present at birth and progresses over time. It is formed by progressive dilatation of post-capillary venules and is associated with hypertrophy and nodularity with increasing age, leading to cosmetic disfigurement and psychological aggravation. It is caused by genetic mosaicism in GNAQ and GNA11 genes. Histopathology is the gold standard for assessment of PWS but it is invasive and may cause scarring. Inadequate characterization of the lesions may predispose to inadequate treatment protocols as well as higher treatment dosages. Clinical evaluation of treatment efficacy is subjective and may not be a representative of actual results. Therefore, an objective visualization modality is required. With evolving technology, numerous optical instruments have been developed for objective evaluation and visualization of subsurface structures. These include VISIA-CR™ system, videodermoscopy, high-frequency ultrasound (HFUS), laser speckle contrast imaging (LSCI), reflectance spectrophotometers and tristimulus colorimeter, laser Doppler flowmetry (LDF), cross-polarized diffuse reflectance imaging system (CDR), reflectance confocal microscopy (RCM), optical coherence tomography (OCT), and spatial frequency domain imaging (SFDI). These semi-quantitative modes of diagnosis are complementary to each other. Some can be used in the clinical setting while others, due to high instrument cost, are limited to the research settings. In this review, we bring to you a brief overview of noninvasive diagnostic modalities in PWS.

Dynamic Optical Coherence Tomography of Cutaneous Blood Vessels in Melasma and Vessel Response to Oral Tranexamic Acid

BACKGROUND AND OBJECTIVES

Melasma may be related to aberrant blood vessels, but there has been no report on the utility of dynamic optical coherence tomography (D-OCT) in studying vessel characteristics in melasma. We studied the characteristics of cutaneous blood vessels in melasma and the effects of oral tranexamic acid (TXA) with D-OCT.

STUDY DESIGN/MATERIALS AND METHODS

Six patients with moderate to severe melasma had a D-OCT scanning of the areas on the face affected by melasma and not affected by it. Three of them had scans within 3 months after starting oral TXA and at a follow-up visit. Blood flow at different depths of the skin and vessel diameter were compared between the melasma and normal skin. For those taking oral TXA, we compared the percent change of blood flow and diameter between the melasma and normal skin.

RESULTS

Dermal blood flow and vessel diameter were greater in the melasma skin than in the normal skin. Oral TXA reduced dermal blood flow in both the melasma and normal skin, but the reduction was more dramatic in the lesional melasma skin.

CONCLUSIONS

D-OCT findings that (i) dermal blood vessels in melasma are increased in size and flow and (ii) oral TXA reduced the vessel size and flow, providing evidence supporting the relationship between melasma and cutaneous blood vessels. D-OCT may be utilized in measuring response to treatments targeting melasma. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Capillary Refill-The Key to Assessing Dermal Capillary Capacity and Pathology in Optical Coherence Tomography Angiography

Background/Objectives

Standard optical coherence tomography angiography (OCTA) has been limited to imaging blood vessels actively undergoing perfusion, providing a temporary picture of surface microvasculature. Capillary perfusion in the skin is dynamic and changes in response to the surrounding tissue's respiratory, nutritional, and thermoregulatory needs. Hence, OCTA often represents a given perfusion state without depicting the actual extent of the vascular network. Here we present a method for obtaining a more accurate anatomic representation of the surface capillary network in human skin using OCTA, along with proposing a new parameter, the Relative Capillary Capacity (RCC), a quantifiable proxy for assessing capillary dilation potential and permeability.

Methods

OCTA images were captured at baseline and after compression of the skin. Baseline images display ambient capillary perfusion, while images taken upon capillary refill display the network of existing capillaries at full capacity. An optimization‐based automated vessel segmentation method was used to automatically analyze and compare OCTA image sequences obtained from two volunteers. RCC was then compared with visual impressions of capillary viability.

Results

Our OCTA imaging sequence provides a method for mapping cutaneous capillary networks independent of ambient perfusion. Differences between baseline and refill images clearly demonstrate the shortcomings of standard OCTA imaging and produce the RCC biometric as a quantifiable proxy for assessing capillary dilation potential and permeability.

Conclusion

Future dermatological OCTA diagnostic studies should implement the Capillary Refill Methods over standard imaging techniques and further explore the relevance of RCC to differential diagnosis and dermatopathology. Lasers Surg. Med. © The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals, Inc.

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

Introduction: Different yellow lasers have been successfully used for the treatment of vascular lesions. This study is aimed to ascertain the role and efficiency of copper vapor lasers (CVLs) and pulsed dye lasers (PDLs) for the treatment of vascular lesions using numerical modeling and to compare results with our clinical experience. In this study we aimed to develop criteria for the choice of more efficient laser exposure mode, investigate more relevant modes of laser irradiation to ensure selective photothermolysis of target vessels, and compare the CVL and PDL efficiency in the course of patients with skin vascular lesions (SVL) treatment. Methods: We performed numerical simulation of the processes of heating a vessel with CVL and PDL to temperatures at which its coagulation could occur. Calculated fluencies were compared with clinical results of laser therapy performed on 1242 patients with skin hemangiomas and vascular malformations (SHVM), including 635 patients treated with CVL and 607 patients treated with PDL. PDL and CVL provided excellent results in 40 and ten days after treatment. The treatment was not painful. Patients did not need anesthesia. Postoperative crusts were greater with PDL than with CVL. Results: Results of computer simulation of a selective vessel heating using PDL and CVL radiation are presented. By results obtained, depth of the location and sizes of vessels that could be selectively heated to more than 75°C are determined. Conclusion: Based on calculated and clinical data, the heating mode for dysplastic vessels using a series of CVL micropulses could be regarded to be safer and more efficient than the mode of a PDL short, powerful pulse.