LETTER TO THE EDITOR Cardiac embolism in a Claude’s syndrome without involvement of the red nucleus A. Serrano-Pozo, E. Montes-Latorre, J. R. Gonza´lez-Marcos and A. Gil-Peralta Department of Neurology, University Hospital Virgen del Rocı´o, Seville, Spain Correspondence: Alberto Serrano Pozo, Department of Neurology, University Hospital Virgen del Rocı´o Av. Manuel Siurot s/n 41013, Seville, Spain (tel.: +34 620 86 13 53; fax: +34 955 01 25 95; e-mail: albserrap@yahoo.es). Keywords: Claude’s syndrome, midbrain infarction, red nucleus, stroke Received 22 October 2005 Accepted 9 December 2005 Claude’s syndrome (CS) is a crossed midbrain syndrome with ipsilateral ocu- lomotor nerve palsy and contralateral hemiataxia. Since first description [1,2] few cases have been reported, most of them related to occlusion of perforating arteries derived from precommunal seg- ment (P1) of the posterior cerebral artery, in the setting of a small vessel disease. However, the exact localization of caus- ative lesion – specially regarding the involvement of the red nucleus – still re- mains controversial. We report a patient with a CS caused by a cardioembolic ventromedial midbrain infarction sparing the red nucleus. A 50-year-old man without previous history of hypertension, diabetes or smo- king, presented with acute onset diplopia and gait instability. Cardiac auscultation revealed an irregular fast heart rate. Neurological examination disclosed a left pupil-spared complete oculomotor palsy and a severe ataxia of right limbs and gait. Speech was normal and there were no motor or sensory deficits. Electrocardiogram showed a previously unknown atrial fibrillation at an average rate of 150 bpm. Blood analyses (inclu- ding lipids), Duplex sonography study of carotid and vertebral arteries, and occip- ital transcranial Doppler study were also normal. Transthoracic echocardiogram disclosed a severe dilated cardiomyopathy with a left ventricular ejection fraction of 15%. Cranial MRI showed an acute left ventromedial midbrain infarction and two acute left cerebellar infarctions (Fig. 1). We report a case of CS with an appropriate ventromedial midbrain infarction on MRI. However, we would like to point out two peculiarities. First, cardioembolism was the most probable etiology. Normal occipital transcranial Doppler study, atrial fibrilla- tion and severe dilated cardiomyopathy found in diagnostic studies, and coexistent acute left cerebellar infarctions on diffu- sion-weighted imaging (DWI), support cardiac source of emboli [3]. The etiology of CS-associated infarctions is assumed to be small vessel disease or undetermined [2,4]. However, although cardioembolism is a very rare cause of pure midbrain infarction [5], it accounts for up to 20% of those who are associated with other pos- terior circulation infarctions [6]. Dysarth- ria, a sign reported in 55% of pure midbrain infarctions [5], was absent in our patient because of sparing of corticobul- bar tract in the cerebral peduncle. Secondly, lesion on MRI seemed to involve only the caudal end of the red nucleus, and was predominantly located below and medial to it. CS is due to involvement of oculomotor nerve fascicles and cerebellar crossing efferent fibers to the thalamus (dentatothalamic fibers). Whether both types of fiber meet only in the red nucleus [2,7,8] or at the superior cerebellar peduncle – at the level of the caudal end of the red nucleus and just medial and below it [9,10], still remains controversial. References 1. Claude H. Syndrome pe´donculaire de la re´gion du noyau rouge. Revue Neurologique 1912; 1: 311–313. 2. Claude H. Ramolissement du noyau rouge. Revue Neurologique 1912; 2: 49–51. 3. Kremer C, Baumgartner RW. Aortic embolism in Claude’s syndrome. Cerebro- vascular Diseases 2002; 13: 142–143. 4. Segura T, Villanueva P, Puentes JM, Zorita MD. Sensory ataxia in Claude’s syndrome. European Neurology 2001; 45: 54–56. 5. Kim JS, Kim J. Pure midbrain infarction. Clinical, radiologic, and pathophysiologic findings. Neurology 2005; 64: 1227–1232. 6. Kumral E, Bayulkem G, Akyol A, Yunten N, Sirin H, Sagduyu A. Mesencephalic and associated posterior circulation infarcts. Stroke 2002; 33: 2224–2231. 7. Leigh RJ, Zee DS. The Neurology of Eye Movements, 3rd edn. New York: Oxford University Press, 1999: 364. 8. Broadley SA, Taylor J, Waddy HM, Thompson PD. The clinical and MRI cor- relate of ischaemia in the ventromedial midbrain: Claude’s syndrome. Journal of Neurology 2001; 248: 1087–1089. 9. Seo SW, Heo JH, Lee KY, et al. Local- ization of Claude’s syndrome. Neurology 2001; 57: 2304–2307. 10. Asakawa H, Yanaka K, Nose T. MRI of Claude’s syndrome. Neurology 2001; 61: 575. Ó 2007 EFNS e1 European Journal of Neurology 2007, 14: e1–e2 doi:10.1111/j.1468-1331.2007.01501.x