Definition: Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.
Input: Abstract: Thirty-four of 87 consecutive patients with subarachnoid hemorrhage from a cerebral aneurysm had a premonitory minor leak. There were 12 men and 22 women, aged 25 to 73 years (mean 44.4 years). Twenty-two had a small and 12 had a large aneurysm located on the internal carotid artery (17 cases), anterior communicating artery (10 cases), middle cerebral artery (five cases), and pericallosal artery (two cases). Fifty-two percent of patients with a minor leak from an internal carotid artery aneurysm had ipsilateral, hemicranial, hemifacial, or periorbital pain. Half of the patients initially saw a physician, but in no case was the correct diagnosis made. Twenty-five patients had a major rupture within 24 hours to 4 weeks after findings suggesting a minor leak, with a mortality rate of 53%. Nine other patients were diagnosed by lumbar puncture or computerized tomography (CT) scanning after initial misdiagnosis and were operated on, without mortality, before a major rupture could occur. The CT scans were negative in 55% of patients with a minor leak, but lumbar puncture, when performed, was always positive. A minor leak prior to major aneurysmal rupture is a common occurrence and, if unrecognized, is associated with a high mortality. Computerized tomography scanning is unreliable in diagnosing this event, and lumbar puncture is the examination of choice once intracranial hypertension has been ruled out.

The minor leak preceding subarachnoid hemorrhage.