The use of ultrasound and MRI in the management of hidradenitis suppurativa: a narrative review.

Hidradenitis suppurativa (HS) is a chronic, inflammatory follicular skin disease that frequently affects the apocrine gland-bearing skin of the axillary, inguinal and anogenital regions. HS has a significant impact on the psychosocial health and quality of life of patients. Diagnosis of HS is typically clinical, and reliant on the ability of physicians to recognize the signs of HS. However, lesions may present at the dermal and subcutaneous skin layers, which cannot be diagnosed by clinical examination alone. Further, the complexity of the clinical presentation of HS can lead to misdiagnosis and delay of diagnosis and appropriate treatment. Imaging is an important tool that can address these issues by detecting inflammatory activity and the early subclinical and dermal features of HS, and accurately characterizing lesional morphology, thereby informing on optimal therapeutic strategies. Overall, imaging is a key tool that can be used in conjunction with clinical examination to improve the management of HS by providing additional information to physicians, and thus optimize clinical decision-making. In this narrative review, we provide an overview of the general role of imaging in the management of HS, and we illustrate HS-specific applications of two pertinent imaging modalities, ultrasound (US) and magnetic resonance imaging (MRI). Finally, based on the literature, we summarize their uses in HS and provide considerations relating to standardizing the practice of US and effectively implementing the use of imaging in the management of HS.