title: [Infiltration of the optic nerve by lymphoma. Diagnosis by magnetic resonance imaging].
abstract: BACKGROUND
  Systemic lymphoma with meningeal involvement is frequent and diagnosis is based on the clinical features, the study of the cerebrospinal fluid and evaluation by magnetic resonance imaging (MRI). Lymphoma with involvement of the orbitary region is more frequent in the optic nerve (ON) than of the eye itself.
  
  
  METHODS
  We report the case of a patient with diffuse non Hodgkin gastric lymphoma of the large B cell type, which coursed with amaurosis, exophthalmus and signs of tumorous meningeal involvement. The ophthalmologic study revealed a thrombosis in the central retinal vein. The MRI exploration only showed an infiltration of the ON with no pathological meningeal enhancement. ON involvement consisted in a peripheral enhancement of the sheath with obliteration of the subarachnoid space. This pattern accounts for the existence of an ischemic neuropathy by direct compression over the central retinal vein and artery. There are different anatomopathologic or ophthalmologic studies of neuropathy of the ON by lymphoma in the literature, but there is only one case of diagnosis by MRI.
  
  
  CONCLUSIONS
  ON involvement can be the only radiological sign in cases of neoplastic tumours with meningeal involvement. The radiological pattern consists in a peripheral infiltration of the sheath of the ON.
authors.affiliation: Unidad de RM.IDI Servicio de Radiología. Hospital Josep Trueta, Girona, España. spedraza@retemail.es
authors.forename: S
authors.initials: S
authors.lastname: Pedraza
authors.forename: M T
authors.initials: MT
authors.lastname: Osuna
authors.forename: R
authors.initials: R
authors.lastname: Guardia
authors.forename: M
authors.initials: M
authors.lastname: Abadal
authors.forename: J
authors.initials: J
authors.lastname: Teruel
authors.forename: J
authors.initials: J
authors.lastname: Vera-Sancho
authors.forename: J
authors.initials: J
authors.lastname: Tarrús
mesh_terms: D006801:Humans; D008223:Lymphoma / Q000175:diagnosis* / Q000473:pathology*; D016393:Lymphoma, B-Cell / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019574:Optic Nerve Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000556:secondary