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

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.

Optical Coherence Tomography as a Diagnosis-Assisted Tool for Guiding the Treatment of Melasma: A Case Series Study

Background/Objectives: Multiple underlying pathomechanisms may lead to melasma, but there has been no report on the use of optical coherence tomography (OCT) to reveal specific pathomechanisms in individual patients and provide individualized treatments accordingly. Using real-time OCT images, we studied the pathomechanisms of melasma in 12 female patients and the effects of individualized treatments. Methods: Patients were divided into good and bad improved groups according to the improvement in hyperpigmentation at month 4. Results: In the bad improved group, all melanin or confetti melanin had significantly decreased at month 2 or month 4 while granular melanin ratio at month or month 4 significantly increased, the most parameters of dendritic-sharped cells (DCs) before and after treatment were not significantly different, the collagen area or collagen density at month 4 significantly decreased. In the good improved group, there was slightly low all melanin/confetti melanin at month 4 and high granular melanin at month 4 in comparison to the bad improved group. Moreover, most of the parameters in the DCs at month 4 significantly increased while most parameters in collagen at month 4 significantly decreased. Conclusions: OCT is useful in revealing the involved pathomechanisms of melasma in individualized patients. Positive treatment results can be achieved through individualized therapy regimen targeting the pathomechanisms.

Non-invasive efficacy assessment of pulsed dye laser and photodynamic therapy for port-wine stain

Port wine stain (PWS) is a congenital vascular malformation that commonly occurs on the face and neck. Currently, the main treatments for port wine stain are pulsed dye laser (PDL) and photodynamic therapy (PDT). However, the efficacy evaluation of PWS mostly relies on the subjective judgement of clinicians, and it is difficult to accurately respond to many small changes after treatment. Therefore, some non-invasive and efficient efficacy assessment methods are also needed. With the continuous development of technology, there are currently many visualisation instruments to evaluate PWS, including dermoscopy, VISIA-CR™ system, reflectance confocal microscopy (RCM), high-frequency ultrasound (HFUS), optical coherence tomography (OCT), Photoacoustic imaging (PAI), laser speckle imaging (LSI) and laser Doppler imaging (LDI). Among them, there are simple and low-cost technologies such as dermoscopy and the VISIA-CR™ system, but they may not be able to observe the deeper structures of PWS. At this time, combining techniques such as HFUS and OCT to increase penetration depth is crucial to evaluate PWS. In the future, the combination of these different technologies could help overcome the limitations of a single technology. This article provides a systematic overview of non-invasive methods for evaluating treatment efficacy in port wine stains and summarises their advantages and disadvantages.

Skin Anatomy and Analysis

This article provides a comprehensive review and strong reference for facial and neck anatomy. An anatomic foundation is built for the dermatologic concepts, techniques, procedures, and surgeries detailed in noninvasive skin treatments. Superficial anatomic landmarks have been established that allow for more nuanced navigation and measurement of facial features. Throughout this article, we discuss key anatomic features of the face and neck, compare dermal thickness in various regions and ethnic anatomic differences, review insertion points of retaining ligaments of the superficial musculoaponeurotic system, and detail diagnostic tools including ultrasound and optical coherence tomography analysis of the skin.

Largest comparative analysis: Novel large spot size 595 nm, high-energy, pulsed dye laser reduces number of treatments for improvement of adult and pediatric port wine birthmarks

OBJECTIVE

Port wine birthmarks (PWBs) are vascular malformations affecting 0.3%-0.5% of newborns with the tendency to persist into adulthood without adequate treatment of the heterogenous ectatic vessels. This study compares treatment outcomes and parameters of the prior generation pulsed dye laser (PPDL) and the larger spot novel generation pulsed dye laser (NPDL) to establish whether a larger spot size laser provides greater clearance with fewer treatments.

METHODS

One hundred and sixty patients were treated with either the PPDL (80 patients) and NPDL (80 patients) with retrospective review of age, body site, laser treatment parameters, number of treatments, and improvement following laser therapy.

RESULTS

Patients treated with PPDL were older on average than patients treated with NPDL (mean 24.8 ± 19.7 vs. mean 17.1± 19.3 years, p < 0.05). The majority of lesions treated with PPDL were located on the face and neck, whereas truncal and extremity sites were more frequently treated with the NPDL. Use of NPDL was associated with a mean maximum spot size of 13.1 mm and mean maximum fluence of 7.3 J/cm2 with pulse durations of 0.45-3 ms, whereas use of the PPDL was associated with a mean spot size of 10.8 mm and mean maximum fluence of 8.8 J/cm2 with pulse durations of 0.45-6 ms. Fifty percent improvement was seen with 8.8 PPDL treatments compared to 4.3 NPDL treatments (p ≤ 0.01) with no significant difference in overall mean improvement between both devices at the chosen parameters. Multiple regression analysis showed that device type, not age or lesion location, was the only statistically significant independent variable to affect the endpoint of at least 50% improvement of the lesion.

CONCLUSIONS

Use of the larger spot NPDL is associated with achieving 50% improvement with fewer treatments.

Current and Emerging Imaging Techniques for Neurofibromatosis Type 1-Associated Cutaneous Neurofibromas

A consistent set of measurement techniques must be applied to reliably and reproducibly evaluate the efficacy of treatments for cutaneous neurofibromas (cNFs) in people with neurofibromatosis type 1 (NF1). cNFs are neurocutaneous tumors that are the most common tumor in people with NF1 and represent an area of unmet clinical need. This review presents the available data regarding approaches in use or development to identify, measure, and track cNFs, including calipers, digital imaging, and high-frequency ultrasound sonography. We also describe emerging technologies such as spatial frequency domain imaging and the application of imaging modalities such as optical coherence tomography that may enable the detection of early cNFs and prevention of tumor-associated morbidity.

[Advances in optical coherence tomography]

Optical coherence tomography (OCT) has been able to establish itself in recent years not only in academic-scientific, but also in everyday dermatological practice. Its focus lies on epithelial tumors of the skin, which can be diagnosed intuitively and within a few seconds. Thus, basal cell carcinomas, actinic keratoses, and different stages of field cancerization can be diagnosed and monitored for response to therapy or possible recurrence. This often helps to avoid invasive sample extraction. Recently, the field of OCT and its latest advancement, dynamic OCT (D-OCT), has been expanded to include non-oncologic dermatological diseases. This encompasses inflammatory dermatoses and the analysis of physiological skin parameters such as hydration. Thanks to automated vascular imaging and the measurement of objective parameters such as epidermal thickness, blood flow at depth, optical attenuation coefficient, and skin roughness, more and more characteristics of the skin can be studied in a noninvasive and standardized way. New potential areas of application are eczema, contact allergic dermatitis, psoriasis, rosacea, telangiectasia, acute and chronic wounds, melasma and nevus flammeus but also melanocytic lesions.