INTRODUCTION
Cherry hemangiomas are common acquired lobular capillary proliferations that increase in prevalence with age.1 Although they are usually asymptomatic, some cases raise a cosmetic concern and may require treatment. Vascular lasers such as the pulsed dye laser (PDL) are often used for this purpose, with the overall success of treatment determined by factors such as lesion depth.2 For example, the PDL has limited penetrance beyond 1.25 mm due to its relatively short wavelength.3
Estimating the lesion depth based on clinical and dermatoscopic examination is difficult and unreliable, and treating with a trial-and-error approach inconveniences both the physician and patient in cases where the lesion is too deep. Therefore, obtaining an accurate depth measurement is crucial in helping the clinician predict treatment outcomes. Imaging modalities such as optical coherence tomography (OCT) may offer a solution to this problem, thereby reducing the burden of unsuccessful or inadequate treatment.
OCT uses low-energy light to visualize structures in the skin by recording the light as it reflects off the tissue at various depths. The OCT device has a scan diameter of 6 mm and can visualize structures up to 2 mm in depth (Michelson Diagnostics, Ltd, UK). This device produces two distinct images: one with a cross-sectional view and a second with an en face view (parallel to the skin surface). Additionally, the device contains a dynamic feature that records motion such as blood flow. This
allows us to quickly and painlessly image vessel architecture, measure vessel diameter, and map the depth of lesions in vivo.
To illustrate the potential of dynamic OCT, we present a cherry hemangioma on the arm of a 25-year-old woman with light skin. The en face view (Figure 1c) allows us to appreciate the horizontal extent of the lesion. The lobular collections appear red, indicating movement, or blood flow in this case. The cross-sectional view seen in Figure 2 allows us to measure the depth of the lesion to the nearest hundredth of a millimeter. In addition to pre-treatment assessment, OCT can be used adjunctively with lasers to monitor change in lesions over time.
The ability to easily measure the horizontal and vertical extent of vascular lesions is unique to OCT and cannot be appreciated with other means such as clinical photos or dermoscopy. As seen in this case, OCT can be a useful tool in practice to help predict the results of laser treatments. Additionally, it can be used alongside treatments to monitor the change in lesions over time. While seemingly promising, prospective clinical trials will be necessary to substantiate the value of OCT in predicting treatment outcomes.
DISCLOSURES
All authors state no relevant conflicts of interest, financial or otherwise.
