Clinical Features, Etiology, and 6-Month Prognosis of Isolated Corpus Callosum Infarction

Abstract

As the largest subcortical commissural fiber, the corpus callosum plays an important role in cerebral functions and has abundant blood supply from bilateral circulation. Isolated corpus callosum infarction (ICCI) may have specific characteristics. The aim of the study is to evaluate the clinical features, etiology, and 6-month prognosis of ICCI. Consecutive patients with acute ICCI treated at the China-Japan Friendship Hospital between June 2012 and June 2016 were retrospectively assessed for clinical and imaging findings. These cases were compared with patients suffering from other isolated supratentorial subcortical infarctions, matched for age, sex, and infarction size (n=60; control group). ICCI etiology and 6-month prognosis were further analyzed. ICCI cases accounted for 2.9% (33/1125) of all acute ischemic strokes and 30 patients were included. Most patients (n=28, 93.3%) presented nonspecific clinical symptoms, and only two (6.7%) with diffuse infarction developed callosal disconnection syndrome (CDS). The splenium was the most frequent site (37.5%). Large artery atherosclerosis (LAA) (n=16, 53.3%) was the most common etiology. Only four (13.3%) patients developed transient ischemic attacks (n=1, 3.3%) or cerebral infarction (n=3, 10%) during the 6-month follow-up. The frequency of good prognosis (modified Rankin score of 1-2 and without cardiovascular events) was higher in patients with ICCI compared with controls (P=0.024). Poor prognosis was associated with multiple cerebrovascular stenosis, diffuse/large infarction, and diabetes (all P<0.05). ICCI is a rare stroke type, frequently involving the splenium; its common etiology is likely LAA. Most patients show nonspecific symptoms, with only a few developing CDS. ICCI generally shows favorable short-term outcome.

Figure 1

Study flowchart.

Figure 2

Male, 38 years, diffusive callosal infarction with the alien hand syndrome caused by Moyamoya disease. Diffusion-weighted imaging shows an extensive infarction involving the genu, body, and splenium of bilateral corpus callosum (a-b). Digital subtraction angiography demonstrates severe stenosis or occlusion of the terminal segments of bilateral internal carotid arteries, as well as proximal segments of bilateral anterior cerebral arteries and middle cerebral arteries with formation of Moyamoya vessels (black arrows) (c-d).

Figure 3

Male, 53 years, callosal infarction caused by anterior cerebral artery dissecting aneurysm. Diffusion-weighted imaging (DWI) shows acute infarction in the right corpus callosum splenium (a-b). Three-dimensional digital subtraction angiography (DSA) confirms long segmental dilatation of the right anterior cerebral artery (ACA) (long white arrow) with distal concentric stenosis (c). Axial contrast-enhanced high-resolution magnetic resonance imaging (MRI) clearly reveals the enhanced wall of the ACA and an intima flap in the arterial lumen forming the "double-lumen sign" (white arrow) (d).

Figure 4

Infarctions at different sites of the corpus callosum and their affected vessels. (a-d) Male, 69 years, left hemiparesis. Diffusion-weighted imaging (DWI) shows a new infarction of the right genu (a). Computed tomographic angiography (CTA) and digital subtraction angiography (DSA) reveal complete occlusion of the cavernous segment of the right internal carotid artery, collateral compensation from the left to the right anterior circulation via the anterior communicating artery, and severe stenosis of the A1 segment of right anterior cerebral artery (white arrow) (b-d). (e-f) Male, 75 years, right hemiplegia. DWI shows a new infarction of the left body (e). Magnetic resonance angiography (MRA) shows that the affected vessel is the severe stenotic pericallosal artery (white arrow) (f). (g-h) Female, 57 years, dizziness. DWI shows an isolated infarction of the right splenium (g). CTA shows that the P1 segment of right posterior cerebral artery has occluded (white arrow) (h).