ABSTRACT
PURPOSE: To identify and compare magnetic resonance imaging (MRI) characteristics, with and without intravenous contrast medium, of cavernous synovial hemangiomas and cystic synovial hyperplasia. MATERIAL AND METHODS: Four cases of cavernous synovial hemangioma and five of cystic synovial hyperplasia of the knee were studied retrospectively. The patients (5 F and 4 M; 15-25 years of age) all had long-standing knee pain. At clinical examination we observed elastic swelling and pain without significant joint effusion. The patients underwent conventional radiography and MRI without and following intravenous contrast medium before arthroscopic biopsy. RESULTS: The radiographs were interpreted as negative in all patients. MRI examination without contrast medium revealed a similar multicystic appearance for both lesions. Following intravenous contrast agent administration, cavernous synovial hemangiomas demonstrated avid, rather homogenous enhancement, whereas cystic synovial hyperplasia demonstrated less intense, peripheral enhancement only. Arthroscopy with histological examination of the lesions confirmed the MRI diagnosis in every case. CONCLUSION: In our experience, cavernous synovial hemangioma and cystic synovial hyperplasia have a similar appearance on unenhanced MRI, but can be reliably differentiated on the basis of enhancement characteristics following intravenous contrast administration.
Subject(s)
Hemangioma, Cavernous/diagnosis , Joint Diseases/diagnosis , Knee Joint/pathology , Magnetic Resonance Imaging , Synovial Membrane/pathology , Adolescent , Adult , Arthralgia/diagnosis , Arthroscopy , Biopsy , Contrast Media/administration & dosage , Cysts/pathology , Diagnosis, Differential , Female , Humans , Hyperplasia , Image Enhancement/methods , Injections, Intravenous , Male , Retrospective StudiesABSTRACT
Sertoli cells (SCs) provide immune protection and nutritive support to the developing germ cells in the testis. Sertoli cells have also been shown to provide immune protection to islets transplanted outside the testes. In this study, the ability of these cells to diminish the infiltration/activation of microglia into a neural graft implanted in the lesioned striatum of a hemiparkinsonian rat was investigated. Human neuron-like cells (hNT neurons) were implanted either alone or in combination with rat SCs. Three months later, the animals were sacrificed and immunohistochemistry was performed to determine the survival of the xenografted neurons as well as microglial infiltration/activation. Cotransplantation of the SCs with the hNT neurons increased graft survival and was associated with an increase in graft size. Furthermore, there were fewer microglia present in the grafted tissue of the cotransplantation groups. These results show that SCs retain their immunosuppressive ability even within the brain. As immune responses to grafted neural tissue within the central nervous system become better understood, this ability of the SCs to provide localized immunosuppression to the transplanted tissue may become more important. This is particularly true as the search for alternative sources of neural tissue to treat neurodegenerative diseases expands to encompass other species.
