Meningioma de la Vaina del Nervio óptico (MVNO). ？La radioterapia es el actual patrón de cuidados?: a propósito de un caso y revisión de la literatura

primary optic nerve sheat meningioma (onsm) is a rare tumor, whose diagnosis and therapeutic management have varied in a substantial manner over the last few years. the appearance and development of diagnostic imaging techniques such as high resolution computerized tomography and nuclear magnetic resonance have allowed earlier and more precise diagnoses. the introduction of conventional radiation therapy in the late 1970s, alone or in combination with surgery, and above all the introduction of fractionated stereotactic radiotherapy and three-dimensional conformal intensity-modulated radiotherapy (3dcrt) have provided very efficient alternative therapies with a relatively low toxicity. in this article we first review the embryological development, anatomy, natural history, and surgical treatment, and then describe the role of radiotherapy (rt) in the considered entity, indicating how it can be integrated in the pattern of present day care. we analyse the different radiotherapy techniques, from the most elementary, such as conventional rt, followed by 3dcrt up to the most sophisticated such as stereotactic fractionated radiotherapy, all based on our experience in one case.