Earliest clinical sign of raised intracranial pressure is:

Ref: Harrison's Principles of Internal Medicine, 18ed.Explanation:Early Manifestations of Acute Raised ICTHeadacheProjectile Vomiting w ithout nauseaExtraocular muscle palsyAltered level of consciousnessBack painPapilledema.Other ManifestationsIf papilledema is prolonged, it may lead to visual disturbances, optic atrophy, and blindness.The headache is classically a morning headache which may wake them from sleep.The headache is worse on coughing / sneezing/ bending, and progressively worsens over time. There may also be personality or behavioral changes.In addition to the above, if mass effect is present writb resulting displacement of brain tissue, additional signs may include pupillary dilatation, ahducens palsies, and the Cushing's triad. Cushing's triad involves an increased systolic blood pressure (widened pulse pressure), bradycardia, and an abnormal respiratory patternIn infants and small children, the effects of ICP differ because their cranial sutures have not closed.In infants, the fontanels, or soft spots on the head where the skull bones have not yet fused, bulge when ICP gets too high.Papilledema, or the swelling of the optic disc, can be a reliable sign that ICP is elevated.