Perforator infarcts account for a quarter of all strokes and portend a favorable prognosis. Except, there are 20-30% cases where the deficits worsen over the ensuing hours to days, and lead to significant disability. The underlying pathophysiology of these processes has still not been clearly elucidated. The distinction between microatheroma causing proximal branch atheromatous disease v/s degenerative lipohyalinosis distally was beautifully elucidated by Dr.Caplan in 1989. But these two disparate processes are still not widely recognized. There have been several studies over the years trying to identify markers of progression in small subcortical strokes, and diabetes, pure motor stroke, hypertriglyceridemia and parent artery atherosclerosis have been identified. 


Jeong et al. hypothesized that atherosclerotic process would produce a greater contribution to early neurologic deterioration (END) compared with small vessel pathologies in small subcortical strokes(<20mm). They performed analysis on a prospectively collected large stroke registry of 4961 patients at Seoul National University Bundang Hospital between July 2007 and July 2013 to investigate associations between concomitant neuroimaging markers and END. 2 authors blinded to clinical data assessed MRIs for degree of white matter hyper intensity, cortical micro bleeds, old lacunar infarcts and parent artery stenosis (patients with stenosis >50% were excluded). Of the 587 eligible patients with small subcortical strokes, END occurred in 13.5% cases, mostly from stroke progression(enlargement of infarct size), at about 40 hours from onset causing an NIHSS increment of 2.3 points. Appropriate binary logistic regression models revealed that relevant artery stenosis and branch atheromatous lesions were significantly associated with occurrence of END in the cohort. These findings corroborate and reinforce Caplan’s description of lacunas actually being comprised of 2 different pathophysiologies, with atheromatous ones having potential for progression. This may potentially underlie the benefit of dual anti platelet therapy in these patients noted in the CHANCE trial. As we await results from POINT trial, neuroimaging is helping us understand pathophysiology of lacunar strokes better.