SUMMARY An approach to the controversy of the physiopathology and classification of ischemic stroke is attempted in this study. The computed tomographies (CT) of 88 patients with transient ischemic attacks (TIA), 46 with reversible ischemic neurologic deficits (RIND) and 70 with ischemic strokes with minimum residuum (SMR) are analysed. The incidence of focal ischemic lesions on CT is 25% in TIA and RIND and 35% in SMR, when the study was performed after the first 24 hours. The incidence of cerebral infarction was much lower when the CT was performed within the first 24 hours after the clinical event. No significant differences in size or location of the infarction were found between the different groups. Deep infarctions were smaller than superficial ones. TIA duration correlated neither with the incidence of CT abnormalities nor with the size of the lesions. 6 Although TIAs and completed strokes are usually managed as different conditions, clinical experience shows that completed strokes with minimum residuum are in many aspects similar to long lasting TIAs or to reversible ischemic neurological deficits (RINDs). In order to study the differences and correlations between these groups we analysed the features of CT performed in patients diagnosed of TIA, RIND and completed ischemic stroke with minimum residuum (SMR). The results obtained can be useful in order to achieve a practical classification for the management and study of focal cerebral ischemia.
Material and MethodsTwo hundred and four patients with the diagnosis of focal cerebral ischemia have been analysed. All were studied in the Neurology Department within a month after the stroke. The diagnosis was based upon clinical and CT findings. Patients with a history of previous completed strokes were excluded. In all the patients at least one CT was performed after the current neurological event. Depending on clinical symptoms the ischemia was considered to occur either in the carotid system or in the vertebrobasilar system. The differences in clinical evolution permitted classification in three groups: 1: TIAs. When focal neurological symptoms lasted less than 24 hours. 2: RINDs. When neurological symptoms or signs lasted more than 24 hours but cleared completely before one month. 3: SMR.From the Department of Neurology and Section of Neuroradiology, "1 de Octubre" University Hospital, Madrid, Spain.Address correspondence to: Dr. L. Calandre, Servicio de Neurologica, Hospital "I de Octubre," Ctra. de Andalucia, Madrid, Spain.Received October 13, 1983; revision #1 accepted January 17, 1984. When after one month mild neurological signs persisted which did not hamper the basic daily activities of the patient. CTs were performed in a 160 x 160 matrix. Focal ischemic lesions included parenchymatous low-density areas and focal areas of dilatation of a ventricle or a cistern. The area of the low-density lesion was measured in the slice in which the width of the lesion was greatest, giving the results in real brain dimensions. Depending on their location the l...