Abstract
Small Infarctions account for about 40% of the cases of cerebral infarction. With the development of the CT scan has come the opportunity to expand our knowledge of the clinical presentation, etiology, and pathophysiology of small infarctions. This papne will deal with the clinical manifestations of cases of small infarctions of the basal ganglia, as demonstrated by CT scan. For purposes of the study, small infarctions have been defined as those which exhibit a low density area less than 15mms in diameter on CT scan. During the presentation we will emphasize the correlation of small infarctions of the basal ganglia with transient ischemic attacks.
Two hundred twenty-three patients with symptoms suggestive of cerebral ischemic infarction were studied by CT scan. In 42.4% of the patients small infarctions of the basal ganglia found on CT scan; of these 65 patients were also studied by angiography.
The clinical presentation of 60 patients with small infarctions of the basal ganglia was compared with that of 41 patients with major cerebral artery occlusion. About half of the patients exhibited a similar degree of weakness in the affected upper and lower extremities. In most of the other patients the upper extremity was more involved than the lower extremity. However, only 3.3% of the patients with small basal ganglia infarctions demonstrated complete hemiplegia as compared with 36.6% of the patients with major artery occlusion. Half of the patients with basal ganglia infarction had no sensory impairment.
Sixty-five per cent of the patients with small infarctions of the basal ganglia showed good recovery compared with 17% of the patients with major artery occlusion cerebral infarctions.
Motor deficits were mild in patients with lesions in the anterior limb or genu of the internal capsule, whereas the patients who sustained small infarctions in the posterior two-thirds of the posterior limb generally had much more marked motor involvement.
There was a striking difference on the prognosis for improvement of the motor deficit when the patients were divided into those with lesions less than 10mm in diameter and those with lesions 10-15mm in diameter.
Of the 65 patients with small infarctions of the basal ganglia demonstrated on CT scan who also were studied angiographically 39 (or 60%) had normal arteriograms.
In 21.7% of the patients with small infarctions of the basal ganglia a past history of TIAs was found, compared with 15.6% of the group without lesions on the CT scan and only 9% of the patients with infarctions elsewhere on CT scan. In 61.5% of the cases of small infarction who had a history of TIAs their stroke was occurred within one day after the last TIA whereas this short interval between TIA and stroke was not prominent in the major artery occlusion group. In 10 of the cases with small infarction the pattern of neurological involvement was similar between the TIAs and stroke.
Five of 65 cases with low density area on basal ganglia were diagnosed transient ischemic attack clinically. Two of 5 cases with transient ischemic attack reveals the positive contrast enhancement on CT scan, two weeks or 17 days later from onset.
