Medically resistant juvenile myasthenia gravis following thymectomy: Role for FDG PET/CT

Thymectomy is part of a multimodal treatment strategy for juvenile myasthenia gravis. Symptoms that persist following thymectomy may be due to residual or ectopic thymic tissue. We report the use of FDG PET/CT to locate residual thymic tissue following thymectomy in a 10 year old girl with acetylcholine-receptor-antibody-positive myasthenia gravis, who remained refractory to medical therapy. The patient subsequently underwent completion thymectomy with improvement but not remission of her condition. •Thymectomy may be part of multimodal therapy for myasthenia gravis.•Persistent symptoms following thymectomy may be due to residual thymic tissue.•Residual thymic tissue can be difficult to detect using conventional imaging.•FDG PET/CT can be used to detect residual thymic tissue.