Conventional and Polarized Dermoscopy Features of Dermatofibroma

Abstract

To evaluate dermoscopic features and patterns of dermatofibromas using conventional and polarized light dermoscopy. Design: Dermatofibromas were imaged using conventional nonpolarized contact dermoscopy (NPD), polarized contact dermoscopy (PCD), and polarized noncontact dermoscopy, followed by evaluation and comparison of dermoscopic features of the lesions. Setting: Dermatology clinic specializing in pigmented lesions. Patients: Fifty patients with dermatofibromas. Results: The most common features of dermatofibromas observed with NPD and PCD were central white scarlike patches (37 [74%] and 42 [84%], respectively), brown globulelike structures (21 [42%] and 22 [44%]), vascular structures (24 [48%] and 22 [44%]), and a peripheral fine pigmented network (36 [72%] for both). A newly described feature observed with PCD was a central white patch characterized by shiny white streaks. With polarized noncontact dermoscopy, the most characteristic feature was a central pink hue or "vascular blush" (44 [88%]) and visibility of blood vessels (41 [82%]). The most common pattern identified with NPD and PCD was the combination of a peripheral pigmented network and a central white patch in 28 (56%) and 31 (62%) of lesions, respectively. With polarized noncontact dermoscopy, the most common pattern was a central pink hue with a peripheral pigmented network (23 [46%]). There was good to excellent agreement when comparing NPD with PCD images, but there was a variable level of agreement when polarized noncontact dermoscopy images were compared with NPD and PCD images. Conclusions: Conventional and polarized light dermoscopy are not equivalent but may be complementary. This study highlights some salient differences. We were able to identify new dermoscopic features and patterns not previously described with conventional dermoscopy. These new criteria can aid in the diagnosis of dermatofibroma.

Differences in Dermoscopic Images from Nonpolarized Dermoscope and Polarized Dermoscope Influence the Diagnostic Accuracy and Confidence Level: A Pilot Study

“…However, there are some differences when comparing PD with NPD 8,10 . In general, the PD allows better visualization of structures deep in the skin, like blood vessels.…”

Differences in Dermoscopic Images from Nonpolarized Dermoscope and Polarized Dermoscope Influence the Diagnostic Accuracy and Confidence Level

“…However, studies have demonstrated some striking differences in the colors and dermoscopic structures observed with NPDs and PDs 8,10 . In this study, we evaluated whether these differences can impact physicians' diagnostic accuracy and confidence levels in examining pigmented skin lesions.…”

The significance of crystalline/chrysalis structures in the diagnosis of melanocytic and nonmelanocytic lesions

“…[5][6][7] However, there are clinically relevant and notable differences between lesion appearance under polarized dermatoscopy (PD) and non-PD. 8,9 In particular, PD has allowed identification of new dermatoscopic structures not previously seen with non-PD. 10 Shiny, bright white, orthogonally oriented linear streaks, detected exclusively with PD, represent one example of such structures (Fig 1).…”

“…10 Shiny, bright white, orthogonally oriented linear streaks, detected exclusively with PD, represent one example of such structures (Fig 1). 8,11,12 These bright white lines are also metaphorically known as crystalline or chrysalis structures (CS). The CS are observed in skin lesions with increased amount of dermal collagen, and are visible as a result of the interaction of polarized light with the birefringent properties of collagen.…”

“…12 The CS are frequently visualized in dermatofibromas (DFs) and scars but can also be seen in basal cell carcinomas (BCC), Spitz nevi, and melanomas. 8,12 The prevalence of CS among melanocytic neoplasms and among various nonmelanocytic lesions is currently unknown. More importantly, the clinical significance of this novel dermatoscopic structure has not been established.…”