Diagnostic value of high-frequency ultrasound (HFUS) in evaluation of subcutaneous lesions

Preliminary study on assessing skin changes in Henoch-Schönlein purpura patients using high-frequency ultrasound and shear wave elastograph

Henoch-Schönlein purpura (HSP) is a prevalent allergic vasculitis. We aimed to investigate the characteristics of skin lesions and assess the degree of the skin damage in HSP patients using high-frequency ultrasound (HFUS) and shear wave elastography (SWE). By leveraging these imaging modalities, we sought to provide an objective and quantitative method for the clinical assessment of HSP, offering valuable insights for the evaluation and management of this condition. Thirty patients diagnosed with HSP were included in the study group (Group B). Among them, patients were further categorized into three subgroups based on the timing of evaluation: Group B1 consisted of patients at the time of admission, Group B2 included patients at the time of discharge, and Group B3 comprised patients at the time of discontinuation of treatment. The control group (Group A) consisted of 30 healthy individuals from the Health Management Center. General clinical data were systematically gathered from both groups. 20 MHz HFUS and SWE were used to assess the thickness and stiffness of the dermis and hypodermis on the left anterior tibial skin of both groups. Laboratory parameters, including WBC, CRP, ESR, and IgE, were documented for the case group, and their correlations with MEmean, MEmax, and MEmin were analyzed. It was found that compared to Group A, the thickness and stiffness of the dermis and hypodermis were significantly increased in the Groups B1 and B2, with dermal stiffness also increased in the Group B3 (all P < 0.05). However, no significant differences were observed in the thickness of the dermis and hypodermis, as well as in the stiffness of hypodermal between the Group B3 and Group A (all P > 0.05). This study showed that the overall skin thickness and stiffness of HSP lesions increased compared to group A. HFUS and SWE can monitor the clinical efficacy of HSP and quantitatively assess the extent of skin involvement in HSP patients, providing clinicians with a precise ultrasound basis for more objective evaluation of treatment outcomes.

Integrating vascularity into the pattern classification of pilomatricomas on ultrasound provides a more competent approach for discriminative evaluation

BACKGROUND

Pilomatricoma has various manifestations on color Doppler ultrasound, and a differential diagnosis is challenging. The objective of this study was to investigate which characteristics of skin lesions on color Doppler ultrasound are effective in distinguishing pilomatricoma from epidermoid cyst and dermatofibrosarcoma protuberans.

MATERIALS AND METHODS

Records of patients with pilomatricomas (n = 63), epidermoid cysts (n = 76), and dermatofibrosarcoma protuberans (n = 19) who underwent color Doppler ultrasound evaluation and surgical excision were reviewed. The anatomical distribution and color Doppler ultrasound characteristics of these lesions were analyzed. The 63 pilomatricomas were categorized into five types based on their color Doppler ultrasound characteristics, and the roles of these five types in the differential diagnosis of the aforementioned diseases were studied.

RESULTS

Pilomatricomas, epidermoid cysts, and dermatofibrosarcoma protuberans exhibited some similar characteristics. Dominantly markedly hyperechoic or hyperechoic appearance, posterior acoustic shadowing, and the presence of vascularity were the major characteristics of pilomatricomas. The pilomatricomas could be categorized into five types, with type II having a diagnostic performance of sensitivity of 65.08%, specificity of 98.95%, area under the receiver operating characteristic curve (AUC) of 0.743, positive predictive value of 97.62%, and negative predictive value of 81.03% for the diagnosis of the aforementioned skin diseases.

CONCLUSION

A combination of dominantly markedly hyperechoic or hyperechoic appearance, posterior acoustic shadowing, and the presence of vascularity exhibits higher diagnostic performance for the differential diagnosis of pilomatricomas, epidermoid cysts, and dermatofibrosarcoma protuberans.