Rapid resolution of signs of primary intracerebral haemorrhage in computed tomograms of the brain

Abstract

Computed tomography of the brain plays an important part in the management of stroke, both in those cases in which diagnosis is uncertain1 and to differentiate haemorrhagic from ischaemic stroke. Although deciding which type of stroke is present may not affect the management of many patients, it is important if treatment with anticoagulants or carotid surgery is being considered. When such treatment is being considered it is vital that patients with primary intracerebral haemorrhage are correctly identified as anticoagulation is dangerous and carotid endarterectomy inappropriate. It may also be advisable to exclude primary intracerebral haemorrhage before treatment with aspirin is started, although whether aspirin predisposes to extension of the stroke or recurrence in cases of primary intracerebral haemorrhage is not known. Differentiating between haemorrhagic and ischaemic stroke on clinical grounds is not sufficiently reliable to allow these management decisions to be made2 and is not improved by examination of the cerebrospinal fluid.3 Clinical scoring systems, such as the recently described Allen score, 3 improve the reliability of the clinical assessment but are insensitive in identifying mild strokes due to small intracerebral haemorrhages. It is the patients with mild strokes, however, who have most to gain from secondary preventive measures. In the weeks alter a primary intracerebral haemorrhage the high density area on computed tomography is replaced by a smaller isodense or hypodense area. Sometimes these changes occur rapidly and may make primary intracerebral haemorrhage indistinguishable from infarction if tomography is delayed. If this fact is not considered then inappropriate treatment may be given. Little has been written about the clinical implications of these rapid changes after primary intracerebral haemorrhage: several of the major medical and neurological textbooks do not mention the problem.4-7 We present five cases of primary intracerebral haemorrhage that show how easy it is to misdiagnose the type of stroke if the timing of computed tomography is not taken into account. © 1987, British Medical Journal Publishing Group. All rights reserved.