Acute diffusion-weighted imaging lesion patterns predict progressive small subcortical infarct in the perforator territory of the middle cerebral artery.

Abstract

Single small subcortical infarct (SSSI) is generally considered to have a fair outcome. However, early neurological deterioration (END), a relatively unfavorable clinical course occurring during the acute phase of infarction, is not uncommon. The aim of this study was to investigate the relationship between lesion patterns detected by diffusion-weighted imaging (DWI) and the presence of END in patients with acute SSSI in the perforator territory of the middle cerebral artery (MCA). Three hundred twelve patients with acute SSSI in the perforator territory of MCA were prospectively recruited from Jinling Hospital between January 2010 and May 2013. Acute DWI lesion patterns were classified as proximal SSSI (pSSSI) or distal SSSI (dSSSI) patterns, according to the relationship between lesion location and the parent artery. Neurological deficits were evaluated using the National Institutes of Health Stroke Scale (NIHSS) at admission and continued over the following 72 h 1-3 times a day. END was defined as an increase in NIHSS score ≥ 2 points during the first 72 h after admission. Of the total 312 patients, the pSSSI pattern was found in 139 (44.55%) patients and the dSSSI pattern in 173 (55.45%) patients. Statistical analysis suggested that the indicators for small-artery disease (hypertension and leukoaraiosis) and atherosclerosis (diabetes mellitus and cerebral atherosclerosis) significantly differed according to lesion patterns (P < 0.05). During hospitalization, 88 (28.21%) patients experienced END. Univariate analysis revealed that female sex (P = 0.004), pSSSI pattern (P < 0.001), initial NIHSS (P = 0.001), lesion diameter (P = 0.005), ipsilateral large-artery stenosis (P = 0.008), and concomitant intracranial atherosclerotic stenosis (P = 0.021) were significantly associated with END. After adjusting for confounding factors, pSSSI pattern was an independent predictor of END (OR 1.871, 95% CI 1.095-3.198, P = 0.022). In the further subgroup analysis of patients with different etiologies, pSSSI pattern was found to be independently associated with END in patients with large-artery atherosclerosis (OR 3.593, 95% CI 1.268-11.057, P = 0.026) and in patients with small-artery disease (OR 2.523, 95% CI 1.121-5.676, P = 0.025), but not in patients with cardioembolism (OR 0.854, 95% CI 0.147-4.953, P = 0.861). pSSSI pattern was closely related to END in acute SSSI caused by large-artery atherosclerosis and small-artery disease in the perforator territory of the MCA.