Objective: Central nervous system post-transplant lymphoproliferative disorder (CNS-PTLD) is a rare disease that presents with non-specific signs and symptoms. The purpose of this article is to present the imaging appearances of CNS-PTLD by magnetic resonance imaging. We highlight the differential diagnostic considerations including primary central nervous system lymphoma, glioblastoma, cerebral abscess, and metastatic disease. This is an important topic to review since in daily practice the diagnosis of CNS-PTLD is often not initially considered when present due to its rarity and the lack of radiologists' familiarity with the disease. Conclusion: Knowing the unique imaging features of CNS-PTLD narrows the differential diagnosis, facilitates the diagnostic work-up, and optimizes making the diagnosis. Advanced MRI data for CNS PTLD is limited but is promising for helping with narrowing the differential diagnosis.

We present the case of a 52-year-old woman who presented to the emergency department with chest and neck pain. Initial cervical spine magnetic resonance imaging shows an abnormal flow void in the left vertebral artery, which prompted a computed tomographic angiogram. This demonstrated a hyperdense thickened ascending aortic wall, which extended into the great vessel origins. Clinically and radiographically interpreted as an acute aortic syndrome and/or intramural hematoma, the patient underwent ascending aortic repair with graft. An unusual aortic and/or periaortic mass was encountered in surgery and final pathology demonstrated IgG4 periaortitis. A rare clinical disease, IgG4-mediated processes are often mimickers of other pathologic entities and frequently lead to misdiagnosis. All pathologically similar, IgG4-mediated disease processes can involve the pancreas, salivary glands, orbits, retroperitoneum, and the vasculature.