Preeclampsia remains one of the leading causes of maternal morbidity and mortality in pregnant women. preeclampsia occurs in 7% to 8% of pregnancies. Preeclampsia is a multisystem progressive disorder characterized by the new onset of hypertension and proteinuria or the new onset of hypertension and significant end-organ dysfunction with or without proteinuria after 20 weeks of gestation or postpartum. Preeclampsia is a potentially severe disease associated with maternal complications. Cerebral oedema is predominantly vasogenic and may be related to failure of cerebral autoregulation with subsequent hyperperfusion, blood brain barrier disruption, and endothelial cell dysfunction.~The optic nerve with its dural sheath cover is considered a window to central nervous system. The subarachnoid space surrounds the optic nerve and communicates freely with the cerebral subarachnoid space. Changes in the optic nerve sheath diameter (ONSD) mirror the changes in the ICP as increases in the ONSD correlates with increase in the ICP.~Magnesium sulphate (MgSO4) is a drug that is routinely used in the treatment of preeclampsia and prevention of eclamptic fits. Currently, several mechanisms have been proposed by researchers to explain the neuroprotective effect of MgSO4 .Dexmedetomidine is a potent alpha-2 adrenergic receptor agonist. dexmedetomidine-induced stimulation of postsynaptic alpha-2 adrenergic receptor on the cerebral blood vessels can cause cerebral vasoconstriction and decrease cerebral blood flow.
The present study is designed to evaluate the differences in the effect of Mg sulphate alone and dexmedetomidine as an adjuvant to Mg sulphate on intracranial pressure when administered intravenously in cases of pre-eclampsia