339 Case Reports Ataxic Hemiparesis Following Thalamic Infarction Jelis Boiten, MD, and Jan Lodder, MD We describe a 73-year-old man with ataxic hemiparesis following infarction of the ventrolateral nucleus of the thalamus demonstrated by computed tomography and magnetic resonance imaging. Cerebellar ataxia was most likely due to interruption of the dentatorubrothalamocortical fibers at the level of the injured ventrolateral nucleus. Hemiparesis was probably caused by local edema compressing the corticospinal tract in the adjacent posterior limb of the internal capsule. We believe this to be the first reported case of classic ataxic hemiparesis following thalamic infarction. {Stroke 1990^21^39-340) A taxic hemiparesis, first described by Fisher and Cole1 in 1965, consists of hemiparesis and ^ cerebellar ataxia on the same side of the body.2 Ataxic hemiparesis is usually caused by lacunar infarction in the contralateral posterior limb of the internal capsule, in the pons, or in the corona radiata1-4 but may also be caused by a hemorrhage or a tumor.5-7 We report a case of ataxic hemiparesis in which computed tomography (CT) and magnetic resonance imaging (MRI) showed an infarct in the contralateral ventrolateral nucleus of the thalamus. Case Report A 73-year-old man suddenly developed dysarthria and weakness of his right arm and leg with unsteadiness of gait. There was no history of hypertension, diabetes, cardiac disease, or peripheral vascular disease. On examination the next day, he had a regular pulse of 76/min. Blood pressure was 150/80 mm Hg. There were no carotid bruits, and cardiac examination was normal. He was alert and fully oriented. Neurologic examination showed a slight rightsided hemiparesis with an extensor plantar response. Finger-to-nose and heel-to-shin tests showed cerebellar-type right-sided dysmetria, hypermetria, and intention tremor out of proportion to the degree of weakness. Sensation was normal. His hemiparesis disappeared after 4-5 days, while his ataxia persisted. After 4 weeks there was only clumsiness of his right hand, with slight ataxia on the finger-to-nose test. Results of electrocardiography, 24-hour electrocarFrom the Department of Neurology, University Hospital Maastricht, Maastricht, The Netherlands. Address for reprints: J. Boiten, Department of Neurology, University Hospital Maastricht, PO Box 1918, 6201 BX Maastricht, The Netherlands. Received March 17, 1989; accepted September 28, 1989. FIGURE 1. Computed tomogram showing recent hypodense lesion in ventrolateral part of thalamus, with involvement of ventrolateral nucleus. Right side of body appears on left side of figure. diographic (Holter) monitoring, echocardiography, and duplex carotid sonography were normal. Serum cholesterol concentration was slightly elevated. CT scan on day 4 revealed a hypodense lesion in the ventrolateral nucleus of the contralateral thalamus, compatible with a recent infarction (Figure 1). MRI 1 year later showed the same infarct in the left thalamus (Figure 2). There were no other lesions visible in the internal capsule, corona radiata, brainstem, or cerebellum. Downloaded from http://stroke.ahajournals.org/ by guest on June 29, 2016 340 Stroke Vol 21, No 2, February 1990 from the contralateral cerebellar dentate nucleus (the dentatorubrothalamic projection).15 From the ventrolateral nucleus, fibers run to the sensorimotor cortex.15 Cerebellar ataxia in our patient was most likely caused by interruption of the dentatorubrothalamocortical fibers at the level of the injured ventrolateral nucleus. Hemiparesis was probably caused by initial local edema compressing the adjacent corticospinal tract in the posterior limb of the internal capsule because MRI did not reveal involvement of the internal capsule. The hemiparesis clearing much more rapidly than the hemiataxia supports this assumption. Our case illustrates that the ventrolateral part of the thalamus takes part in the cerebellar projection to the sensorimotor cortex, disruption of which at different levels can induce the classic lacunar syndrome of ataxic hemiparesis. References 1. Fisher CM, Cole M: Homolateral ataxia and crural paresis: A vascular syndrome. / Neurol Neurosurg Psychiatry 1965; 28:48-55 2. Fisher CM: Ataxic hemiparesis. A pathologic study. Arch Neurol 1978;35:126-128 3. Sage JI, Lepore FE: Ataxic hemiparesis from lesions of the corona radiata. Arch Neurol 1983;40:449-450 4. Huang CY, Lui FS: Ataxic-hemiparesis, localization and clinical features. Stroke 1984;15:363-366 5. Bendheim PE, Berg BO: Ataxic hemiparesis from a midbrain mass. Ann Neurol 1981;9:405-407 6. Helweg-Larsen S, Larsson H, Henriksen O, Sorensen PS: FIGURE 2. Magnetic resonance image 1 year later showing Ataxic hemiparesis: Three different locations of lesions studsame lesion in left thalamus. ied by MRI. Neurology 1988;38:1322-1324 7. Mori E, Tabuchi M, Yamadori A: Lacunar syndrome due to intracerebral hemorrhage. Stroke 1985;16:454-459 8. Bogousslavsky J, Regli F, Ghika J, Feldmeyer JJ: Painful Discussion ataxic hemiparesis. Arch Neurol 1984;41:892-893 "Painful ataxic hemiparesis" following thalamic 9. Verma AK, Maheshwari MC: Hypesthetic-ataxic-hemiparesis infarction and "hypesthetic ataxic hemiparesis" in in thalamic hemorrhage. Stroke 1986;17:49-51 10. Lee N, Roh JK, Myung H: Hypesthetic ataxic hemiparesis in a thalamic hemorrhage and infarction have been thalamic lacune. Stroke 1989;20:819-821 reported.8-10 Sole unilateral cerebellar ataxia has 11. Garcin R: Syndrome ce're'bello-thalamique par lesion localised been described following contralateral thalamic du thalamus: Avec une disgression sur le "signe de la main infarction.1112 Murthy13 described a case of ataxic creuse" et son intdrfit semiologique. Rev Neurol (Paris) 1955; 93:143-149 hemiparesis following thalamic infarction, but the 12. Garcin R, Lapresele J: Incoordination c6r6belleuse du memlesion appeared to be located in the head of the bre inferieur par lesion localised de la region interne du caudate nucleus instead of in the thalamus.14 CT and thalamus contralateral. Rev Neurol (Paris) 1969;120:5-13 MRI in our patient showed an infarct in the contra13. Murthy JMK: Ataxic hemiparesis —Ventrolateral nucleus of lateral thalamus. To our knowledge, this is the first the thalamus: Yet another site of lesion (letter). Stroke 1988; reported case of classic ataxic hemiparesis following 19:122 14. Gomez CR, Gomez SM: Thalamic lesion producing ataxic infarction strictly confined to the thalamus. hemiparesis (letter). Stroke 1988;19:1181 The lesion was located in the ventrolateral part of 15. Brodal A: Neurological Anatomy. Oxford, Oxford University the thalamus, with involvement of the ventrolateral Press, 1981, pp 359-370 nucleus. From experimental evidence it was concluded that the ventrolateral nucleus receives fibers KEY WORDS • hemiplegia • lacunar infarction • thalamus Downloaded from http://stroke.ahajournals.org/ by guest on June 29, 2016 Ataxic hemiparesis following thalamic infarction. J Boiten and J Lodder Stroke. 1990;21:339-340 doi: 10.1161/01.STR.21.2.339 Stroke is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231 Copyright © 1990 American Heart Association, Inc. All rights reserved. Print ISSN: 0039-2499. Online ISSN: 1524-4628 The online version of this article, along with updated information and services, is located on the World Wide Web at: http://stroke.ahajournals.org/content/21/2/339 Permissions: Requests for permissions to reproduce figures, tables, or portions of articles originally published in Stroke can be obtained via RightsLink, a service of the Copyright Clearance Center, not the Editorial Office. Once the online version of the published article for which permission is being requested is located, click Request Permissions in the middle column of the Web page under Services. Further information about this process is available in the Permissions and Rights Question and Answer document. Reprints: Information about reprints can be found online at: http://www.lww.com/reprints Subscriptions: Information about subscribing to Stroke is online at: http://stroke.ahajournals.org//subscriptions/ Downloaded from http://stroke.ahajournals.org/ by guest on June 29, 2016