Dermatologic ultrasonography is a new field that has been growing exponentially in the last 10 years. It has multiple applications that can modify patient management, such as the assessment of benign ...and malignant cutaneous tumors, vascular anomalies, inflammatory dermatologic entities, aesthetic complications, and nail lesions. Compared with other imaging techniques such as computed tomography or magnetic resonance imaging, ultrasonography has the highest axial spatial resolution and has benefited from the development of high- and ultra-high-frequency probes that could even reach 70 MHz. The daily use of ultrasonography in dermatology has been reported to improve the accuracy of diagnoses, the tracking of activity, and the assessment of severity in common dermatologic conditions, which certainly can support better treatment of patients.
Hidradenitis suppurativa is a complex disease of chronic evolution and difficult management. Imaging, particularly color Doppler ultrasound, has demonstrated a wide range of subclinical anatomic ...abnormalities, allowing modification of the clinical assessment of severity of the disease and therefore management of patients. Sonography supports early and more precise diagnosis and staging by providing critical objective information in real time. The richness of these data can also support assessment of the pathogenesis of the disease, allow monitoring of patients, and contribute to clinical trials. MRI can support the diagnosis of extensive anogenital and deep lesions.
Background High variable-frequency ultrasound is a recently available technique capable of clearly defining skin layers and deeper structures that also provides local perfusion patterns obtained in ...real time. Objectives The aim of the study was to assess the performance of variable-frequency ultrasound in the evaluation of skin lesions. Methods We performed a retrospective study of 4338 skin ultrasound examinations in predominantly localized skin lesions, and in a group of 130 healthy controls. We determined ultrasound sensitivity, specificity, and statistical level of certainty, and compared ultrasound diagnoses with clinical diagnoses. Results Referring diagnosis was correct in 73% of the lesions, and addition of ultrasound increased correctness to 97% ( P < .001 for the difference). Ultrasound overall sensitivity was 99%, specificity was 100%, and statistical diagnostic certainty was 99% Limitations Ultrasound in its current version cannot detect lesions that are epidermal only or that measure less than 0.1 mm in depth. Conclusions Ultrasound is a reliable adjuvant for the accurate and precise diagnosis of skin lesions.
Nowadays, there are several applications of ultrasound in the field of dermatology, and the numbers continue to grow. This imaging technique can allow the study of the skin, the nail, and even the ...hair. The objective of this review is to provide an insight into the reasons for performing this examination, including technical considerations, the sonographic anatomy, and to discuss the sonographic characteristics of common dermatologic entities.
To test the capability of 70-MHz ultrasound for detecting initial ultrasound signs of hidradenitis suppurativa (HS) linked to severity.
A cross-sectional study of the ultrasound images of patients ...with HS was conducted and compared with a healthy control group. Detection and identification of early subclinical ultrasound signs in the lesional and perilesional areas of the HS cases in comparison with the control group were performed. Statistical analyses included mean, dispersion measures, the Kruskal-Wallis test, and bivariate and multivariate ordered logistic regression studies. Significance was assessed at P < .05.
A total of 139 patients with HS met the criteria and showed abnormalities of the hair follicles such as a curved shape, ballooning, and protrusion into pseudocysts, collections, or tunnels (donor of keratin sign). Significant increases in the sizes of the hair follicles and hair shafts were found in HS cases. The following ultrasound signs were significantly linked to severity: a connecting band between the base of adjacent hair follicles (bridge sign), a fragment of the hair shaft extruding through a dilated hair follicle (sword sign), and retained cylindrical fragments of keratin in the dermis. Two patterns of fragmentation of the keratin were detected: multifragment and cylindrical.
Ultrasound can detect early HS signs that are significantly linked to severity and 2 types of fragmentation of the keratin, which could support the generation and perpetuation of the fluid collections and tunnels. These ultrasound signs can help prompt diagnosis and management, the development and testing of medications, and the measure of treatment outcomes in HS.
Background Fistulous tracts in hidradenitis suppurativa (HS) are key signs of severity and their clinical evaluation alone may be limited for assessing their presence and morphology. There is also a ...need to determine the factors that allow reversibility of the anatomic changes in HS. Objective We sought to categorize fistulous tracts in HS. Methods A retrospective study of color Doppler ultrasound images of cases with positive clinical and sonographic criteria of HS with fistulous tracts was performed. The sonographic staging of HS, location, and anatomic characteristics of the tracts were registered and graded. Statistical analysis for correlating variables was performed using bivariate and multivariate studies. Results In all, 52 patients presenting 96 fistulous tracts met the criteria. Morphology was defined and a sonographic classification into 3 types of fistulae was developed. Type 3 concentrated 71% of the cases presenting communicating tracts, and type 2, 29%. Types 2 and 3 represented 63% of patients with multiple fistulous tracts. Fistulous tracts types 2 and 3 were significantly correlated with age 35 years or older and groin location. Limitations Ultrasound cannot detect lesions less than 0.1 mm. Conclusion Fistulous tracts in HS can be categorized using ultrasound, which may support earlier and more precise management.
To explore the capability of very high-frequency ultrasound (US; 50-71 MHz) to detect the normal morphologic characteristics of the hair follicles and tracts, sebaceous glands, Montgomery glands, ...apocrine glands, and arrector pili muscles.
A retrospective study, approved by the Institutional Review Board, evaluated the normal US morphologic characteristics of the hair and adnexal structures in a database of very high-frequency US images extracted from the perilesional or contralateral healthy skin of 1117 consecutive patients who underwent US examinations for localized lesions of the skin and 10 healthy individuals from December 2017 to June 2018. These images were matched with their counterparts from the database of normal histologic images according to the corporal region. The Cohen concordance test and regional mean diameters of the hair follicles and adnexal structures were analyzed.
The normal hair follicles and tracts, sebaceous glands, Montgomery glands, apocrine glands, and arrector pili muscles were observed on US images and matched their histological counterparts in all the corporal regions. There was significant US concordance (κ = 0.82; P = .0001) among observers. Regional mean diameters (millimeters) of the hair follicles, sebaceous glands, and apocrine glands are provided.
The hair follicles and tracts, sebaceous glands, Montgomery glands, apocrine glands, and arrector pili muscles are detectable with very high-frequency US, including some regional and anatomic variants. Knowledge of their normal US appearances is a requisite for detecting subclinical changes, understanding the physiopathologic characteristics, and supporting the early diagnosis and management of common dermatologic diseases.
Complete visualization of lesions is critical for the accurate diagnosis and management of dermatological diseases. Currently, the most readily available technologies used by dermatologists include ...dermoscopy and photography. Nevertheless, ultrasound has emerged as a useful non-invasive modality in dermatology, which can be added to the clinical examination supporting an early and more accurate diagnosis. Moreover, there are significant technological advances in recent years, such as the development of handheld devices and ultra-high frequency probes that have expanded the integration of ultrasound into daily dermatology practice. In this article, we reviewed the most common applications of ultrasound in the field of dermatology.
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