HRCT, CT Cisternography and MR Cisternography in Assessment of CSF Rhinorrhea

Inclusion Criteria: * (1) patients with active traumatic or non traumatic CSF leakage. * (2) patients with adequate organ function. Exclusion Criteria: * (1) Patients known to have contrast hypersensitivity. (2) Patients with any general contraindication to MRI as presence of para magnetic substance as pacemakers or with claustrophobia. (3) Patients with contraindication to lumbar puncture: * Infection near the puncture site, fever, sepsis. * New focal neurological signs or seizures. * Increased intra cranial tension. * Space occupying lesion. * Vertebral deformity, retropulsion, severe vertebral osteoarthritis or degenerative disc disease renders procedures more technically difficult. * Coagulopathy. * Patient refusal.