NeuroradiologyE2334. The Many Faces of Neurosarcoidosis: A Review of the Imaging Manifestations and Current Literature
Blanchard A, Mourad H, Palacios E, Kream E. Tulane University School of Medicine Department of Radiology, New Orleans, United States
Address correspondence to A. Blanchard (email@example.com)
Background Information: Sarcoidosis is a granulomatous, multisystemic disorder of unknown origin. Neurosarcoidosis is an uncommon although important subset of sarcoidosis with significant morbidity. The diagnosis of neurosarcoidosis can be challenging to make given its poorly understood pathogenesis and protean clinical manifestations. Radiologic imaging has evolved to become an indispensable tool in the diagnosis and management of the disease. A well-informed radiologist can provide invaluable guidance to referring clinicians. Given our institution’s patient demographics, we encounter this disease process with somewhat regularity, and have compiled an extensive case library over several decades. We believe that sharing our unique experience with this disease and a review of current knowledge on the subject will help educate other radiologists and clinicians on the topic.
Educational Goals/Teaching Points: The exhibit aims to first, familiarize the audience with the epidemiologic data and diagnostic criteria of neurosarcoidosis. Second, the myriad radiologic patterns of disease will be discussed in detail, with added emphasis on their relation to clinical findings and management and prognostic implications. Lastly, differential diagnoses will be thoroughly investigated, as many pathologic processes can mimic neurosarcoidosis.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques: Neurosarcoidosis is thought to represent an inflammatory response to an unknown antigen. The most common site of inflammation is the basilar meninges. Inflammatory changes are believed to then spread to cranial nerves or along the perivascular (Virchow-Robin) spaces to the brain parenchyma or spinal cord. Lesions can present as a discrete mass or masses or as diffuse encephalopathy or vasculopathy. Clinical presentation does not always correlate with imaging findings, particularly with cranial nerve and pituitary involvement. Contrast-enhanced MRI is the preferred imaging modality due to its superior soft tissue contrast resolution. The imaging findings of neurosarcoidosis are variable and can be divided into several categories: meningeal, parenchymal including hypothalamic and pituitary, cranial nerve and spinal disease. Invasion of the CNS can also occur through contiguous osseous, orbital, and sinonasal structures.
Conclusion: Knowledge of the multiple radiologic findings of neurosarcoidosis in conjunction with clinical information will enable radiologists and clinicians to reliably diagnose and manage neurosarcoidosis.