Case report http://dx.doi.org/10.3345/kjp.2011.54.12.515 Korean J Pediatr 2011;54(12):515-517 A case of idiopathic isolated hypoglossal nerve palsy in a Korean child Ji Hoi Yoon, MD1, Kyung Lae Cho, MD1, Hae Jung Lee, MD1, Seo Hui Choi, MD1, Kyung Yul Lee, MS2, Sung Koo Kim, MD3, Jun Hwa Lee, MD1 1Department of Pediatrics, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, 2Depart­ ment of Physical Education, Kyungnam University College of Education, Changwon, 3Department of Pediatrics, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea Received: 25 March 2011, Revised: 4 March 2011 Accepted: 14 July 2011 Corresponding author: Jun Hwa Lee, MD Department of Pediatrics, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Hapseong 2-dong, Masanhoewon-gu, Changwon 630-723, Korea Tel: +82-55-290-6140, Fax: +82-55-290-6044 E-mail: ljh3643@skku.edu Hypoglossal nerve palsy (HNP) is an uncommon neurological abnormality that can provoke characteristic clinical signs, including unilateral atrophy of the tongue musculature. We present the case of a healthy 11-year-old Korean male who was admitted to the outpatient department of our institution with acute onset dysarthria, tongue fasciculations, and right-sided tongue weakness upon awakening. His evaluation included a virology work-up, neck magnetic resonance imaging (MRI), brain MRI, and otorhinolaryngological physical examination; all tests were normal and showed no evidence of inflammation. Fifteen days after the onset of symptoms, the patient recovered completely. Herein, we report a case of idiopathic isolated HNP in a Korean male. Key words: Hypoglossal nerve, Palsy, Child Copyright © 2011 by The Korean Pediatric Society This is an open­access article distributed under the terms of the Creative Commons Attribution Non­Commercial License (http://creativecommons.org/licenses/by­ nc/3.0/) which permits unrestricted non­commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Introduction The importance of the hypoglossal nerve, or cranial nerve XII, is often devalued; many times its description is reduced to a few words under “the last four cranial nerves,” because damage to the 12th nerve rarely causes much inconvenience. Indeed, this nerve is considered a convenient “spare”, suitable for transplantation surgery to reanimate a paralyzed face1). The motor composition of cranial nerve XII is highly complex and incompletely understood, and the nucleus consists of 4 topographically distinct subnuclear columns. Hypoglossal nerve palsy (HNP) is an uncommon neurological abnormality. Damage to this nerve produces characteristic clinical manifestations, including unilateral atrophy of the tongue musculature. The causes of HNP include known tumors (49%), trauma (12%), stroke (6%), hysteria (6%), surgery (5%), multiple sclerosis (5%), infection (4%), Guillain­ Barre neuropathy (4%) and idiopathic (3%)2). This report describes a pediatric case of idiopathic isolated HNP with Solumedrol treatment for 12 days with complete recovery after 15 days. Case report A 11­year­old Korean male was admitted to the outpatient depart­ ment with sudden onset dysarthria, tongue fasciculations, and right­ sided tongue weakness upon awakening (Fig. 1A). 515