Fig. 1

a Case 1, a 2-year-old boy presented with right facial paralysis accompanied by right limb fatigue for 48 h. The muscle strength of his right upper and lower limbs was grade II. The strength of his left limbs was normal. The right nasolabial groove was shallow, and the angle of his mouth was skewed to the left. MRI results showed that the left lenticular nucleus was involved. b Case 2, an 8-year-old boy had sudden hemiplegia of his right limb for 6 h without any inducement. His pronunciation was slurred. The muscle strength of his right upper and lower limbs was grade 0. The strength of his left limbs was normal. His right nasolabial groove was shallow. MRI results showed that the left lenticular nucleus with the caudate head was involved. c Case 3, a 1-year-old girl had left limb weakness for 48 h after falling from a height of 50 cm. The muscle strength of her left upper and lower limbs was grade III. Her left nasolabial groove became shallow, and the angle of her mouth was skewed to the right. The right lenticular nucleus with thalamus involvement was shown on MRI. The images from left to right were acquired by T1, T2, FLAIR and DWI. d The MRA of case 2 showed that the left anterior A1 segment was slightly thinner than the right anterior A1 segment, and the left lenticular artery was not clear