Long-term survival in six cats with mediastinal cysts.

Case Series Summary: Mediastinal cysts were diagnosed as incidental findings in six cats evaluated for non-thoracic disease, including staging for historical bladder leiomyosarcoma, flea dermatitis and hairballs, and hyperthyroidism. Radiographically, the cysts appeared as soft tissue opacities cranial to the heart. Ultrasound revealed the masses to be thin-walled, single lumen, anechoic, fluid-filled structures.