The significance of the hyperintense middle cerebral artery sign on MR T1WI in acute and subacute cerebral infarction

Abstract

Objective To explore the clinical significance of the hyperintense vessel sign(HVS) of middle cerebral artery on T1-weighted images in acute and subacute cerebral infarction. Methods In this retrospective study, 92 patients [54 males, 38 females, aged 41-94 years, mean age (66.0±13.9) years] with acute and subacute cerebral infarction in middle cerebral artery territory in the First Affiliated Hospital of Anhui Medical University were enrolled from January 2013 to March 2015. Thirty-four subjects included the patients with other brain disease and normal subjects were enrolled to observe whether HVS appeared in normal brains or other diseases in the same period. All of them were undergone conventional MRI, 68 patients with cerebral infarction were undergone 3D-TOF MRA and/or CTA. HVS sign was observed on T1WI. The extent of cerebral infarction, the degree of vascular lesion, DWI-Alberta stroke program early computed tomographic score (DWI-ASPETS scores) and the clinical manifestations were compared. Results HVS did not appear in 34 patients without cerebral infarction. It was observed in 43 of 92 patients with cerebral infarction. There were no significant differences in general clinical situation (age, with underlying diseases) between positive HVS group and negative HVS group (all P values>0.05). The mean infarction size was (4.0±1.1) lobes in positive HVS group and (2.5±0.9) lobes in negative HVS group. The scores less than or equal to 6 were found in 36 patients (83.7%, 36/43)in positive HVS group and in 13 patients (26.5%, 13/49) in negative HVS group based on DWI-ASPETS. It was significantly different between two groups (all P values<0.01). The muscle strength of patients was lower in positive HVS group than that in negative HVS group at admission (Z=1.978, P=0.048). MRA and /or CTA found 71.4%(25/35) patients had arterial occlusion and 28.6%(10/35) patients had arterial stenosis in positive HVS group, which was 45.5%(15/33) and 39.4%(13/33) in negative HVS group. It was significantly different between two groups (χ2=5.724, P<0.05). Conclusions T1WI HVS indicate arterial occlusion or severe stenosis, which can be used as an indicator of poor prognosis and is helpful to understand the cause of infarction, guide clinical treatment and judge prognosis. Key words: Infarction, middle cerebral artery; Brain infarction; Thrombosis; Magnetic resonance imaging; Hyperintense vessel sign