Role of Dermoscopy in Laser Therapy

Abstract

Lasers have revolutionized the interventional dermatology field over the last two decades. Dermatologic conditions previously untreatable are now treated with lasers and lights. A large number of laser systems with advances in technologies have expanded applications of lasers for conditions like birth marks, acne scars, wrinkles, pigmentation, etc. Newer avenues and protocols are now set to treat skin conditions with lasers. The applicability of laser for any indication is dependent on laser tissue interaction which is well documented. For a successful outcome with laser therapy, a right end point of treatment should be achieved. The laser physician often adjusts parameters for laser therapy depending on tissue response, the ultimate aim being achieving optimum outcome with minimum side effects. Gadget based skin evaluation techniques are now an integral part of dermatology and are extending to interventional dermatology too. Application of dermoscopy before, during, and after lasers in various indications has been documented and reviewed. The representative cases highlighted in article emphasize the added dimension to non-invasive diagnostic capabilities of a dermatologist by enabling subsurface microscopy and enhancing therapy outcomes, and incorporation of these into daily practice offers value addition to not only evaluation but also gauging response to therapies. Use of dermoscopy before, during, and after laser therapies is an invaluable non-invasive tool to assess the right indication, initiate appropriate priming, achieve good end point, gauge untoward side effects, achieve good results, and engage patient confidentiality. Comparison of high magnification digital images is also enabled by digital videodermoscopy. Structured studies and protocols are needed to standardize the use of dermoscopy integrated with laser procedures.

Keywords: Dermoscopy; end point; lasers; tissue interaction.

Figure 1

Residual tattoo seen as bluish homogenous hyperpigmentation (orange arrow) immediately after treatment with Q-switched Nd:YAG seen by bleached hair and fractional carbon dioxide laser for fast pigment elimination seen as opaque white dots (blue arrow) equally spaced after fractional photothermolysis. (Fotofinder handyscope, non-polarised,10x)

Figure 2

(a) Acne scars after MNRF on day 5: microcrusts as black dots (red arrow) uniformly spaced correlating to coagulated areas, whitish linear area corresponds to atrophic acne scars (blue arrow). (b) Post-treatment after 2 weeks of MNRF: post-inflammatory erythema and pigmentation seen as uniform reddish-brown globules (blue arrow) indicate high energy and degree of heating, improvement in underlying scar and texture as well as pigment dilution seen. (Fotofinder handyscope, non-polarised,10x)

Figure 3

(a) Tattoo on forearm scarred with hypopigmentation and atrophy with residual tattoo after trichloroacetic acid application. (b) Clinical image after single session of Q-switched Nd:YAG (QSNY) combined with fractional carbon dioxide laser showing tattoo elimination with residual PIH. (c) Dermoscopic image of tattoo with hyperpigmented scar before treatment shows sharp linear globular bluish pigment band (blue arrow) corresponding to tattoo ink with brown pigment in reticular triangular pattern (orange arrow) corresponding to PIH with residual ghost shadow. (d) Dermoscopic image after single session of QSNY combined with fractional carbon dioxide laser showing clearance of bluish pigment band of tattoo ink (blue arrow) and decrease in brown pigment in reticular triangular pattern (orange arrow) compared to Figure 3c. (Fotofinder handyscope, non-polarised,10x)

Figure 4

(a) Erythemato-telangiectatic melasma pattern. (b) Dermoscopic image before laser toning shows pigment globules in reticuloglobular pattern (blue arrow) with enhanced vascularity. (c) Clinical improvement of melasma after four sessions of laser toning. (d) Dermoscopic improvement at four sessions of laser toning, showing decrease in pigment globules (blue arrow), note marked reduction in vascular component. (Fotofinder handyscope, non-polarised,10x)

Figure 5

(a) Steroid abuse in melasma seen on dermoscopy as increased vascularity, reticular globular pigmentation, intermediate frame shows, (b) rebound pigmentation after steroid withdrawal and accentuation of melasma, (c) last frame shows improvement after fluence laser toning. (Fotofinder handyscope, non-polarised,10x)

Figure 6

(a) Clinical image of lichen planus pigmentosus (LPP) before treatment. (b) Clinical image of LPP after treatment with QS: Nd YAG laser. (c) Dermoscopic image of LPP right cheek stable disease shows perifollicular and perieccrine bluish pigment globules (orange arrow) with follicular sparing. (d) Dermoscopic clearance after single laser session of 1064 QS laser spot size 6 mm, 2.4 mj, evaluated at 1 year after one session, shows marked decrease in pigment globules (blue arrow). (e) Dermoscopic image of left cheek LPP shows perifollicular and perieccrine bluish pigment globules (orange arrow) with follicular sparing. (f) Dermoscopic image of improvement left cheek after single session of 1064 QS laser spot size 6 mm, 2.4 mj, evaluated at 1 year after one session. Dermoscopy shows marked decrease in pigment globules (blue arrow). (Fotofinder handyscope, non-polarised,10x)

Figure 7

(a) Tattoo before QSNY laser, dermoscopy shows linear conglomerate of bluish pigment globules (orange arrow) in heterogenous pattern with few regression areas (blue arrow) corresponding to tattoo design. (b) Tattoo immediately after QSNY laser, dermoscopy shows bleaching of hair, erythema, and purpura over lasered area seen as solid white linear lines (bleached hair-blue arrow), red areas (purpura/erythema-orange arrow), and areas of blanching (c) Tattoo post 8 weeks of one session seen as tattoo pigment reduction, fading of tattoo shape with residual tattoo pigmentation after 1064 QSNY, dermoscopy highlights residual pigment globules with loss of sharp border (blue arrow). Fotofinder non poralized handyscope used at 10x magnification

Figure 8

(a) Tattoo before Q-switched Nd:YAG (QSNY) laser. Dermoscopy shows linear conglomerate of bluish pigment globules (orange arrow) in heterogenous pattern corresponding to tattoo design. (b) Tattoo clearance with ghost shadow after QSNY laser. Dermoscopy highlights residual pigment globules with loss of sharp border (orange arrow). (Fotofinder handyscope, non-polarised,10x)

Figure 9

Dermoscopy immediately after laser hair reduction shows perifollicular edema, hair ejection seen as perifollicular whitening and black dots (orange arrow) corresponding to charred hair stubs. (a) Clinical image of chin hirsutism before laser hair reduction. (b) Clinical image after six sessions of laser hair reduction. (c) Corresponding dermoscopic image before and (d) after six sessions of laser showing hair number reduction and terminal to vellus conversion and hair reduction. (Fotofinder handyscope, non-polarised,10x)

Figure 10

(a) Vitiligo lower lip before 308nm excimer lamp treatment. Dermoscopy shows homogenous areas of white areas seen as a glow (orange arrow) with sparing of hair. (b) Vitiligo lower lip after 30 sessions of 308nm excimer system with topical mometasone. Dermoscopy shows partial repigmented network (orange arrow) and hypertrichosis compared to Figure 10a. (Fotofinder handyscope, non-polarised,10x)

Figure 11

(a) Onychomycosis of great toe, dermoscopic image before laser shows opalescent white areas representing fungal colony (orange arrow). (b) Substantial clearance of distal onychomycosis of great toe by quasi-pulse Q-switched Nd:YAG laser in 3 sessions. Onychoscopy shows clearance of white opalescent areas and presence of whitish-yellowish areas (orange arrow) that are progressing towards distal nail unit