Complete tongue protrusion palsy due to subsequent cryptogenic cortical strokes.

To cite: Sebire D, Rigney L, Cordato DJ. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/bcr-2014207989 DESCRIPTION We describe a 76-year-old right-handed man who presented with acute onset of tongue protrusion palsy without additional neurological deficits or pseudobulbar stigmata. He had previously suffered five strokes. Six months prior to this presentation he had an ischaemic stroke in the right precentral gyrus causing dysarthria with slowed tongue movements. However, he was able to protrude his tongue during that admission. MRI at 24 h following his new presentation showed acute left precentral gyrus cortical infarction involving the most lateral part of the gyrus corresponding to cortical tongue innervation (figures 1A, B). Extensive stroke risk factor work-up did not reveal the stroke mechanism. The patient was categorised as having cryptogenic strokes. His tongue function completely recovered with full tongue protrusion evident after 5 days. It is possible that small infarct size shortened time to recovery. Isolated inability to protrude the tongue has rarely been described following acute stroke. 2 Unilateral precentral gyrus cortical infarction, involving the most lateral part of the gyrus, has been reported to cause isolated contralateral tongue deviation due to disruption of the tongue area of the motor cortex and contralateral innervation of genioglossus (the major muscle responsible for tongue protrusion) as compared with bilateral innervation of other tongue muscles. 2 Complete failure of tongue protrusion may occur after bilateral simultaneous cortical or hypoglossal nerve lesions or tandem ipsilateral peripheral (hypoglossal nerve) and central (cortical) lesions. We postulate that acute cortical infarction with previous infarction of the corresponding contralateral territory 6 months beforehand caused our patient’s isolated tongue protrusion palsy.