The Journal of Emergency Medicine, Vol. 50, No. 4, pp. e195–e196, 2016 Copyright Ó 2016 Elsevier Inc. Printed in the USA. All rights reserved 0736-4679/$ - see front matter http://dx.doi.org/10.1016/j.jemermed.2015.11.009 Visual Diagnosis in Emergency Medicine VISUOSPATIAL NEGLECT FROM STROKE CAUSING A MOTOR VEHICLE COLLISION Ava L. Liberman, MD,* Christina A. Wilson, MD, PHD,† and Brett L. Cucchiara, MD* *Department of Neurology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania and †Department of Neurology, University of Florida, Gainesville, Florida Reprint Address: Ava L. Liberman, MD, Department of Neurology, Hospital of the University of Pennsylvania, 3 West Gates Building, 3400 Spruce Street, Philadelphia, PA 19104 (Figure 1C). The patient was treated with intravenous heparin, and then switched to dual antiplatelet therapy for secondary stroke prevention. He was unable to return to commercial driving. CASE REPORT A 76-year-old right-handed man driving a school bus collided with another vehicle. Video taken at the scene shows the school bus consistently traveling in the wrong lane, on the left side of the center line, until the collision (Video 1). The driver maintained control of the vehicle in the incorrect lane with seeming disregard for the oncoming vehicles to his left (Figure 1A). After the accident, the driver did not recall seeing the other vehicles and denied any symptoms, but was nevertheless taken to the Emergency Department of our hospital for evaluation. Upon neurological examination, the patient was noted to have extinction to double simultaneous stimulation in his left visual field without any motor, language, or sensory deficits, including sight in all visual fields. Magnetic resonance imaging demonstrated an acute infarction in the territory of the right middle cerebral artery (Figure 1B) affecting the right parietal lobe. Computed tomography angiogram revealed a right supraclinoid internal carotid artery stenosis with intraluminal thrombus DISCUSSION Stroke is a rare but important cause of motor vehicle collisions (MVC), with approximately 0.1–0.5% of accidental injuries reported to be precipitated by acute ischemic stroke (1–3). Identification of patients with stroke causing MVC is critical to ensure appropriate stroke treatment, provide guidance as to the safety of a return to driving, and has potentially significant medicolegal implications. Whereas significant motor weakness or discoordination may be obvious findings on examination to raise suspicion for an acute stroke, more subtle deficits such as hemispatial neglect or visual field deficits may be overlooked if a careful neurologic examination is not performed. In this case report, an older man sustained an MVC because of an acute ischemic stroke causing isolated visual neglect. Subjects with hemispatial neglect exhibit defects in attending to or representing information from the contralesional side of space that is not due to a primary sensory, visual, or motor disturbance. The syndrome of neglect is often observed after right hemispheric strokes Streaming video: A brief real-time video clip that accompanies this article is available in streaming video at www.journals.elsevierhealth.com/periodicals/jem. Click on Video Clip 1. RECEIVED: 1 August 2015; FINAL SUBMISSION RECEIVED: 23 October 2015; ACCEPTED: 10 November 2015 e195 e196 A. L. Liberman et al. Figure 1. (A) Photographic still from video footage taken at the scene of the motor vehicle collision by onlookers. (B) Magnetic resonance imaging of the brain showing area of acute infarction (white arrow) in the right parietal lobe. (C) Computed tomography angiogram of the head demonstrating intraluminal thrombus as well as stenosis of the supraclinoid segment of the right internal carotid artery (black arrow). affecting the inferior parietal lobe or nearby temporoparietal junction (4). Testing for extinction to double simultaneous stimulation is commonly used to detect neglect on physical examination and is a component of the National Institute of Health Stroke Scale (5). Extinction occurs when a stimulus can be detected on the affected side when presented alone, but when stimuli are presented simultaneously on both sides, only the stimulus on the unaffected side can be detected (6). Bedside testing for tactile neglect is performed by first verifying that light touch sensation is perceived normally on each side of the body individually, then touching both sides simultaneously while the patient’s eyes are closed. Neglect of one side is present if the patient reports feeling the sensation on only a single side. Extinction to visual stimuli is tested similarly, using confrontational testing of visual fields. Both tactile and visual stimuli should be tested, as neglect may be isolated to a single sensory modality. REFERENCES 1. Finelli PF, Lee N. Stroke and automobile accidents. Conn Med 1996; 60:145–7. 2. Finelli PF, Beland D. Thrombolytic therapy in stroke-related trauma. Conn Med 2004;68:551–3. 3. Fries M, Bickenbach J, Beckers S, Reinartz B, Rossaint R, Kunitz O. Neurological emergencies as causes of accidents. Eur J Emerg Med 2005;12:151–4. 4. Vallar G, Perani D. The anatomy of unilateral neglect after righthemisphere stroke lesions. A clinical/CT-scan correlation study in man. Neuropsychologia 1986;24:609–22. 5. Brott T, Adams HP Jr, Olinger CP, et al. Measurements of acute cerebral infarction: a clinical examination scale. Stroke 1989;20:864–70. 6. Blumenfeld H. The neurological exam as a lesson in neuroanatomy. In: Neuroanatomy through clinical cases. New York: Sinauer Associates, Inc; 2011:55–6:chapter 3. SUPPLEMENTARY DATA Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.jemermed.2015.11.009. Streaming video: A brief real-time video clip that accompanies this article is available in streaming video at www.journals.elsevierhealth.com/periodicals/jem. Click on Video Clip 1.