30 obstetric patients admitted to the HDU in Corniche Hospital for treatment of severe preeclampsia. Patients with the following criteria will be excluded from the current work: Patients undergone cranial or eye surgeries, Patients with known intracranial pathology, Patients suffering from glaucoma or any other eye pathology that prevent clear identification of the optic nerve, and Patients on drugs that may affect the cerebrospinal fluid [based on operator decision].