Ipsilateral stroke in a patient with horizontal gaze palsy with progressive scoliosis and a subcortical infarct.

BACKGROUND AND PURPOSE horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare congenital disorder caused by mutation in the ROBO3 gene. It is characterized by absent horizontal eye movements with progressive scoliosis developing in childhood and adolescence. To our knowledge, both diffusion tensor imaging evaluation in HGPPS patients who present with stroke and truncating stop codon mutation in the ROBO3 gene have yet to be reported. SUMMARY OF CASE we present a man with HGPPS who experienced a left pure motor stroke as a result of a left corona radiata infarct on diffusion-weighted imaging. Diffusion tensor imaging tractography confirmed the presence of uncrossed corticospinal tracts, accounting for the ipsilateral deficit. He was also found to possess a novel ROBO3 stop codon mutation on genetic testing. CONCLUSIONS patients with HGPPS may present with stroke symptoms on the ipsilateral side of the infarct in view of uncrossed corticospinal tracts. Truncating mutation in ROBO3 may provide additional pathophysiologic insights.