High frequency ultrasound with color Doppler in dermatology

Abstract

Ultrasonography is a method of imaging that classically is used in dermatology to study changes in the hypoderma, as nodules and infectious and inflammatory processes. The introduction of high frequency and resolution equipments enabled the observation of superficial structures, allowing differentiation between skin layers and providing details for the analysis of the skin and its appendages. This paper aims to review the basic principles of high frequency ultrasound and its applications in different areas of dermatology.

Figure 1

Non-glabrous skin anatomy. (A) Normal skin histology. (B) HFUS, transverse view. (e) Epidermis. (d) Dermis. (sc) Subcutaneous tissue with the presence of fibrous septa (⇒ )

Figure 2

Scalp. (A) Histology, longitudinal section. (B) HFUS, longitudinal view. (e) Epidermis. (d) Dermis. (sc) Subcutaneous tissue. (⇒) Hypoechoic oblique bands corresponding to hair follicles. (★) Margin of cranial bone

Figure 3

Normal nail unit, longitudinal section. (A) HFUS. (B) Histological section. (➚)Floor plate. (➘) Dorsal plate. (★) Nail matrix. (Δ) Nail bed and (↓) distal phalanx bone

Figure 4

Basal cell carcinoma in the scalp. (A) Clinical aspect. (B) Dermatoscopy presenting arboriform vessels. (C) HFUS, transversal view. Hyperechoic point within the lesion (⇒). (D) Color Doppler. Blood vessels inside and at the base of the lesion (blue and red)

Figure 5

Melanoma. (A) HFUS, longitudinal view. Fusiform hypoechoic lesions affecting the epidermis and dermis. (B) Occupation of the central area of the epidermis and superior dermis by proliferation of anaplastic melanocytic cells, with irregular distribution of melanin pigment. Melanoma, superficial spreading type, Breslow 0.62 mm and Clark level III. Hematoxylin & Eosin 10X

Figure 6

Metastatic melanoma. (A) HFUS, longitudinal view. Epidermis and dermis with normal appearance. In the subcutaneous tissue, irregular lesion with variable echogenicity. (B) Color Doppler. Intralesional vascularity

Figure 7

Psoriasis. (A) Posterior region of the legs. (B) HFUS, transversal view. (B1) Psoriasis plaque. Epidermis with 0.50 mm thickness and dermis with 2.56 mm thickness. (B2) Healthy contralateral region. Epidermis with 0.34 mm thickness and dermis with 1.67 mm thickness. (C) Color Doppler. (C1) Increased blood flow of the affected area, setting up disease activity. (C2) Healthy contralateral region

Figure 8

Plantar wart. (A) HFUS, transversal view. Fusiform hypoechoic lesions localized in the epidermis and in the dermis. (B) Color Doppler. Intense vascularization within the lesion with predominance of arterial vessels. (⬋) Ultrasonographic bilaminar aspect of the plantar region skin

Figure 9

Photoaging. (A) Ventral and dorsal region of the forearm. (B1) HFUS, longitudinal view. Decreased dermis echogenicity (➛). (B2) Discrete degeneration of collagen fibers. Hematoxylin & Eosin 10X. (C1) HFUS, longitudinal view. Subepidermal low echogenicity band (↑). (C2) Solar elastosis. Hematoxylin & Eosin 10X