Imaging in Systemic Sclerosis (Scleroderma)

Systemic sclerosis (SSc) or scleroderma is a multisystem autoimmune disorder characterized by a variable pattern of skin thickening and involvement of visceral organs. The pathophysiology is similar across all organs, which is chronic low-grade inflammation, with vasculopathy and eventual fibrosis. Diagnosis is primarily clinical, particularly in patients with established disease comprising characteristic skin and visceral manifestations, with a supportive role of laboratory and imaging findings. The presence of radiologic signs such as hidebound bowel or a combination of patulous lower esophageal sphincter, pulmonary fibrosis, skin thickening, and Raynaud phenomenon is relatively specific for SSc. Nevertheless, imaging in SSc is primarily used to determine the pattern, severity, and complications of visceral organ involvement, rather than for diagnosis of SSc. Radiologic evaluation in SSc employs a wide gamut of investigations, depending on the organ of interest. For example, US is used for the skin and superficial tissues; fluoroscopy, CT, or MR enterography for the gastrointestinal tract; endoanal US or MRI for the internal anal sphincter; high-resolution CT for the lungs; echocardiography and cardiac MRI for SSc-related pulmonary arterial hypertension (PAH) and cardiac disease; and radiography, CT, or MRI for musculoskeletal involvement. Early diagnosis of treatable features, such as PAH and gastroesophageal reflux, can help reduce the morbidity and mortality associated with SSc. Imaging is additionally useful to prognosticate and monitor the disease. The authors focus on the multisystem, multimodality imaging manifestations of SSc with relevant differential diagnoses to bridge the gaps in knowledge about SSc.