History of lucid interval is present in

.extradural haematoma is the collection of blood in the extradural space between the dura and skull. most common site is temporoparietal region . usually , it is associated with fracture of temporoparietal region. immediately after injury, there is transient loss of consciousness and the patient soon becomes normal. later after 6-12 hours, he again falls ill and condition deteriorates. this is the time taken to develop raising intracranial pressure , coning and its effects. this crucial time gap is caleed lucid interval. (Ref : SRB&;s Manual of Surgery, 5th editin , pg no. 1095)