Perforator Territory Infarction in the Lenticulostriate Arterial Territory: Mechanisms and Lesion Patterns Based on the Axial Location

Abstract

Background: We hypothesized that perforator territory infarcts in the lenticulostriate territory (pLSAIs) may have heterogeneous lesion patterns and stroke mechanisms. Methods: We reviewed prospectively collected patients who developed pLSAIs within 72 h after stroke onset. Lesion patterns were analyzed based on the six axial levels. Based on MR angiography, stenosis of the middle cerebral artery (MCA) was classified into 3 groups. White matter hyperintensities were assessed by Fazeka’s scale of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH). Results: Of 221 patients, 159 were normal, 44 had mild stenosis, and 18 had severe stenosis of the MCA. Larger infarct volume was correlated with the severity of MCA disease (r = 0.289, p < 0.001). Lower lesion patterns were correlated with the severity of MCA disease (r = –0.294, p < 0.001). A higher lesion pattern was correlated with the severity of DWMH or PVH scores (r = 0.205, p = 0.002 in DWMH, and r = 0.137, p = 0.042 in PVH). Conclusions: Patients with MCA disease have larger and lower lesion patterns beginning from the proximal territory of the lenticulostriate artery (LSA). Patients with severe white matter changes have smaller and higher lesion patterns in the distal territory of the LSA.

Single Subcortical Infarction and Atherosclerotic Plaques in the Middle Cerebral Artery

“…These results are consistent with previous studies reporting that dSSI is more often associated with the characteristics of small-vessel disease than pSSI. 5,6 In addition, we found that as many as 51.3% of patients with SSI demonstrated HR-MRI-identified MCA plaques, even if the patient's MRA findings were normal. This result agrees with recent studies reporting that MCA plaques are present in 42% to 60% of patients with lacunar infarction.…”

“…5 Previous studies have shown that dSSI is associated with the characteristics of small-vessel disease, including abundant microbleeds and white matter ischemic changes, whereas pSSI is more often associated with atherogenic characteristics, such as the concomitant presence of atherosclerotic cerebral vessels. 5,6 Recently, studies have reported that high-resolution MRI (HR-MRI) can show the vessel wall structure and, therefore, detect early atherosclerotic changes such as plaques, wall thickening, and arterial remodeling, even in patients with normal findings on magnetic resonance angiography (MRA). 7,8 Because the lesion characteristics of pSSI are similar to those of SSI associated with parental artery disease, 5 pSSI may be more closely associated with HR-MRI-identified MCA plaques than dSSI in patients who do not show parental artery disease on MRA.…”

Distal Single Subcortical Infarction Had a Better Clinical Outcome Compared With Proximal Single Subcortical Infarction

“…These results are consistent with previous studies. 1,4 For example, Cho et al 4 found that patients with dSSI had more severe white matter changes, and Nah et al 1 found that these patients had a higher prevalence of microbleeds and leukoaraiosis compared with patients with pSSI.…”

“…Involvement of the lowest portion of the basal ganglia was considered as an extension to the basal surface of MCA. 4 A diagram for the possible mechanisms of dSSI and pSSI is illustrated in Figure 2. The largest lesion was used to determine the volume of infarction: 1/2×diameter of length×diameter of width×numbers of MRI diffusion-weighted imaging slices of SSI.…”

“…3 Patients with dSSI often have small-vessel diseases manifested as lacune, leukoaraiosis, and microbleeds on imaging studies. 1,2,4 Because most published reports had small number of samples and had not examined differences of clinical outcome in patients with pSSI or dSSI, we investigated such differences in patients with ischemic stroke (IS) in China. Data analyzed from patients with pSSI or dSSI included their vascular risk factors, prevalence of lacune and leukoaraiosis, and clinical outcome.…”