Indian Journal of Dermatology
CORRESPONDENCE
Year
: 2021  |  Volume : 66  |  Issue : 4  |  Page : 413--414

Evaluation of Lichen Striatus by In vivo Reflectance Confocal Microscopy


Dai Hui, Jiang Hong-Yan, Xu Ai-E 
 Department of Dermatology, Hangzhou Third Hospital, Zhejiang, China

Correspondence Address:
Xu Ai-E
Department of Dermatology, Hangzhou Third Hospital, Zhejiang
China




How to cite this article:
Hui D, Hong-Yan J, Ai-E X. Evaluation of Lichen Striatus by In vivo Reflectance Confocal Microscopy.Indian J Dermatol 2021;66:413-414


How to cite this URL:
Hui D, Hong-Yan J, Ai-E X. Evaluation of Lichen Striatus by In vivo Reflectance Confocal Microscopy. Indian J Dermatol [serial online] 2021 [cited 2022 Jan 24 ];66:413-414
Available from: https://www.e-ijd.org/text.asp?2021/66/4/413/326114


Full Text



Sir,

The delineation and naming of Lichen striatus (LS) were proposed by Senear and Caro.[1] Recently, it has been suggested that the disease be renamed something like "blaschkitis," "blaschko dermatitis," or even "Blaschko linear inflammatory skin eruption (BLAISE)" in order to emphasize the distribution of this disorder.[2] LS also called linear lichenoid dermatosis is the appearance of violaceous erythematous papules or hypopigmented papules that follow the lines of blaschko. The differential diagnosis includes linear psoriasis, linear lichen planus, nevus depigmentosus and vitiligo. LS can usually be identified by clinical history and histology of typical lesions. However, biopsy is generally invasive, with injuries, pain and scars which may decrease the compliance of the patients. In vivo reflectance confocal microscopy (RCM) is a non-invasive, repetitive imaging tool that provides real-time images at nearly cellular histological resolution.[3] In this study, we recruited 17 cases with typical lesions to further investigate the imaging features by using RCM.

Seventeen patients (9 females and 8 males) without treatment between 3 and 38 years of age (mean age 10.88 years) were included; 12 patients (70.59%) were characterized by violaceous erythematous papules and 5 patients (29.41%) were characterized by hypopigmented papules. All the cases were recruited prospectively from the Dermatology Department of The Third People's Hospital of Hangzhou.

In vivo RCM imaging was performed using a commercially available, near infrared reflectance mode confocal microscope (Vivascope 1500; Lucid Inc. Rochester, NY, USA), which uses a diode laser at an 830 nm wavelength and a laser power of <20 mW at the tissue level. Because of the low power, no tissue damage occurred. A × 30 water-immersion objective lens with a numerical aperture of 0.9 was used with pure water (refractive index = 1.33) as an immersion medium. This system provides high-resolution images (horizontal resolution of 1.0 μm, vertical optical section thickness of 3.0 μm) to a depth of 200–250 μm in vivo, allowing the visualization of the epidermis and the upper dermis.

Two patients with violaceous erythematous papules and two patients with hypopigmented papules in this study were biopsied. Biopsies of the lesions at the same site of RCM examination were performed for histopathologic analysis. The excisions were fixed in formalin and embedded in paraffin. After routine processing, slides were stained with hematoxylin and eosin.

RCM findings revealed the main features: In basal cell layer and dermo-epidermal junction (DEJ), the annular structure of papillary dermis was blurred and even disappeared, with dense and highly refractive lymphocytes in the superficial dermis [Figure 1]. Inter- and intra-cell mild edema like "sponginess" structures were visible in the stratum spinosum [Figure 2].{Figure 1}{Figure 2}

Histological findings revealed the presence of hyperkeratosis with parakeratosis, spongiosis and liquefaction of basal cells. There was a lymphocytic perivascular infiltrate in the upper dermis [Figure 3].{Figure 3}

In this study, we found the main features of the dense and highly refractive lymphocytes in the superficial dermis for LS, which proved to be very valuable in the diagnosis of LS by RCM. Overall, the above results have demonstrated a high degree of correlation between the observed RCM features and the histologic findings. However, the RCM findings of linear psoriasis revealed the following important features: acanthosis, dilated capillaries in DEJ and microabscesses of Munro at the level of the stratum corneum.[4] We could distinguish between LS and linear psoriasis according to these characteristics. Hypopigmented LS and nevus depigmentosus were appearance of hypopigmented and followed the lines of blaschko clinically. However, we found the main difference between two hypopigmented LS and nevus depigmentosus using RCM. The RCM feature of dense and highly refractive lymphocytes in the superficial dermis was seen in hypopigmented LS and not seen in nevus depigmentosus.[5]

In conclusion, we considered that these RCM imaging features were intuitive and sensitive, which could be used as an important diagnostic indicator of LS using RCM. The RCM could provide effective assistance for the clinical diagnosis and differential diagnosis of LS.

Acknowledgments

This research was supported by Science and Technology Commission of Hangzhou No. 20170533B48.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

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2Taieb A, El Youbi A, Grosshans E, Maleville J. Lichen striatus: A Blaschko linear acquired inflammatory skin eruption (BLAISE). J Am Acad Dermatol 1991;25:637-42.
3Pellacani G, Guitera P, Longo C, Avramidis M, Seidenari S, Menzies S. The impact of in vivo reflectance confocal microscopy for the diagnostic accuracy of melanoma and equivocal melanocytic lesions. J Invest Dermatol 2007;127:2759-65.
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5Lai LG, Xu AE. In vivo reflectance confocal microscopy imaging of vitiligo, nevus depigmentosus and nevus anemicus. Skin Res Technol 2011;17:404-10.