Exploration of Brain Functional Networks in Patients With Hidradenitis Suppurativa Using fMRI

Inclusion Criteria: For Participants With Hidradenitis Suppurativa: * Aged 18 to 45 years. * Diagnosed with hidradenitis suppurativa according to established clinical diagnostic criteria. * Able and willing to comply with the study procedures and follow-up assessments. * Able to provide written informed consent and willing to permit photography of affected skin areas. * No coexisting systemic lupus erythematosus, dermatomyositis, atopic dermatitis, steroid-dependent dermatitis, or other relevant skin diseases. * No use of biologic or small-molecule therapy that may affect hidradenitis suppurativa symptoms within 3 months before enrollment. * Right-handed according to the Edinburgh Handedness Inventory. For Healthy Participants: * Aged 18 to 55 years. * No hidradenitis suppurativa or other chronic skin disease. * No chronic pain disorder. * No major neurological or psychiatric disorder. * Right-handed according to the Edinburgh Handedness Inventory. * Able to provide written informed consent and comply with the study procedures. For the Longitudinal Treatment Cohort: * Meets the eligibility criteria for participants with hidradenitis suppurativa. * Is scheduled to receive biologic or small-molecule therapy for hidradenitis suppurativa as part of routine clinical care, as determined by the treating physician. * Willing and able to complete assessments before treatment and during 3 months of follow-up. Exclusion Criteria: * Participation in another investigational drug study within 1 month before enrollment. * Alcohol or drug abuse or dependence within the previous 3 months. * Current use of medications that may lower the seizure threshold or current use of antidepressant medication. * Previous or current treatment with electroconvulsive therapy, vagus nerve stimulation, or transcranial magnetic stimulation. * Serious cardiac, hepatic, pulmonary, renal, thyroid, hematologic, or other systemic disease; malignant tumor; or another clinically significant abnormality that, in the investigator's judgment, makes participation inappropriate. * Pregnancy or breastfeeding. * Schizophrenia, bipolar disorder, or another major psychiatric disorder. * A neurological condition that may interfere with participation or interpretation of the imaging results, including markedly elevated intracranial pressure, intracranial vascular lesions, impaired consciousness, or inability to cooperate with study procedures. * Any contraindication to magnetic resonance imaging, including intracranial metallic foreign bodies, cardiac pacemakers, incompatible vascular or cardiac implants, or claustrophobia. * Inability to remain still or comply with resting-state functional magnetic resonance imaging procedures. * Unwillingness to allow study data to be collected.