Young patient with aphasia, monoparesis, facial drop, facial sensory loss, diplopia, dysarthria, and vertical gaze palsy.

We present a case of a 40-year-old male without previous medical history and medication who denied tobacco smoking or alcohol abuse. He led a healthy lifestyle, and there were no cardiovascular risk factors in his family history. In October 2012, he experienced acute onset of horizontal diplopia while playing with his child. During the transport to the emergency room, he developed a left-sided facial drop and dysarthria. On arrival, he was immediately moved to the computed tomogra-phy (CT) room as a candidate for intravenous thrombolysis and was examined by a stroke neurologist. At that time, the patient's level of consciousness was slightly drowsy, but he was orientated. His pupils were equal with normal reactions to light. He had horizontal diplopia in either direction, more pronounced on the right side. The right eye was nasally deviated. There was no problem with vertical eye movements. He had facial sensory loss on the left side, left-sided facial drop causing dysarthria, and difficulty with word finding. There were no sensorimotor findings in the upper extremities. He was able to raise his right lower extremity, but could not hold it in the upright position for 5 seconds, and the Babinski sign was present on the right side. The National Institutes of Health Stroke Score was 6. With the suspicion of posterior circulation stroke, a noncon-trast computed tomographic head scan and CT angiography were ordered. There was no pathology on noncontrast computed tomographic scan. Before CT angiography findings were available , the patient's symptoms progressed. He became mute but understood verbal commands and developed a vertical gaze palsy. There was confusion on the localization of the lesion. On the one hand, right-sided weakness and aphasia suggested a left middle cerebral artery syndrome; however, left facial drop and facial sensory loss did not fit this. On the other hand, diplopia with eye movement abnormalities suggested a brain stem lesion. After considering contraindications, the patient received full-dose of intravenous alteplase 1 hour and 14 minutes after symptom onset. CT angiogram showed the basilar artery to be open, but detailed radiologist's report was not available at that time. During the alteplase infusion, the patient's condition improved. He was able to speak in full sentences with paraphasic errors and had continued dysarthria. His left-sided facial drop improved, and there were no facial sensory symptoms. He had still diplo-pia; the right eye was adducted but had conjugate eye movement to the …