Korean J Pediatr 2011;54(12):515-517 • http://dx.doi.org/10.3345/kjp.2011.54.12.515 517 Discussion trauma. Giuffrida et al.15) believed that the occurrence of benign and idiopathic isolated unilateral HNP is more frequent than previously The hypoglossal nerve is underrated, relegated to a few words under reported and proposed that no therapy is required in patients with “the last 4 cranial nerves” in most neurology texts. Damage to the HNP that is likely viral in origin. In the diagnosis of benign HNP, 12th nerve rarely causes much inconvenience; indeed, this nerve is neuroimaging studies (X­ray, CT scan, MR, MR angiography) remain often used in transplantation surgery to reanimate a paralyzed face. In mandatory in order to exclude tumoral, spontaneous, traumatic, or addition to having complex afferent input within the brain stem and rich vascular causes in view of the possibility of a specific or early anticoa­ anastamoses in the neck, the hypoglossal nerve probably carries small gulant treatment. proprioceptive and sympathetic contributions. Its motor composition Our case represents idiopathic isolated HNP in a patient who com­ is highly complex and incompletely understood, and the nucleus con­ pletely recovered within 15 days. However, isolated HNP in children is sists of 4 topographically distinct subnuclear columns1). Keane2) published a review of 26 years of personal experience with cases often an ominous sign of underlying malignancy. Details regarding the patient’s trauma and vaccination history were necessary. An MRI scan of HNP in a large public hospital. He reported on 100 patients ranging of the brain, brain stem and skull base is mandatory, and viral serology, in ages from 8 to 73 years; 51 cases were men and 49 cases were women. particularly for EBV, were useful supplementary investigations. Thirty­one patients had right side HNP, 36 had left side, and 33 had HNP on both sides. He also reported that HNP usually appears as signs rather than symptoms. Tumors, predominantly malignant, pro­ duced nearly half of the palsies (49 cases). Trauma due to gunshots (12 cases) was the second most common cause. Stroke (6 cases), hysteria (6 cases), multiple sclerosis (6 cases), surgery (5 cases), Guillain­Barre neu­ ropathy (4 cases), infection (4 cases), and idiopathic (3 cases) together accounted for about one third of the patients. Boban et al.3) reported on 4 patients with isolated HNP due to dif­ ferent etiologies. The different etiologies were pseudoaneurysm of the right internal carotid artery, 2 aneurysms on the right and left middle cerebral artery, postinfectious acute disseminated encephalomyelitis, and metastatic tumor on the right ventrolateral surface of the medulla oblongata. Combarros et al.4) reported 9 cases of isolated unilateral HNP. In 4 cases, no cause was found, and all the patients had an excellent outcome. In 3 cases, metastatic disease prompted the unilateral HNP. In the other 2 cases, the causes of isolated unilateral HNP were Chiari mal­ formation and dural arteriovenous fistula of the transverse sinus. Tommasi­Davenas et al.5) reported 32 cases of HNP. Seventeen cases were related to predominant malignant tumors. Six cases were of vascular origin, 4 cases were due to head or neck trauma, 4 cases were from various inflammatory processes, and 1 case was caused by Chiari’s malformation. Other case reports of HNP have revealed the causes to be multiple myeloma6), adenoid cystic carcinoma7), pyogenic meningitis8), a late complication of radiation therapy of head and neck carcinoma9), infectious mononucleosis10­11), a complication of post streptococcal infection12), possibly linked to influenza vaccination13), and multiple sclerosis14). Giuffrida et al.15) reported 3 patients with isolated unilateral HNP who experienced an excellent outcome. In 2 cases, the patients had idio­ pathic HNP, and 1 patient was found to have right­sided occipital References 1. Cushing H. The surgical treatment of facial paralysis by nerve anastomosis: with the report of a successful case. Ann Surg 1903;37:641­59. 2. Keane JR. Twelfth­nerve palsy. Analysis of 100 cases. Arch Neurol 1996; 53:561­6. 3. Boban M, Brinar VV, Habek M, Rados M. Isolated hypoglossal nerve palsy: a diagnostic challenge. Eur Neurol 2007;58:177­81. 4. Combarros O, Alvarez de Arcaya A, Berciano J. Isolated unilateral hypo­ glossal nerve palsy: nine cases. J Neurol 1998;245:98­100. 5. Tommasi­Davenas C, Vighetto A, Confavreux C, Aimard G. Causes of paralysis of the hypoglossal nerve. Apropos of 32 cases. Presse Med 1990; 19:864­8. 6. Tucker D, Musuka C. Isolated 12th cranial nerve palsy as a complication of multiple myeloma. Br J Haematol 2004;124:1. 7. Adams H, Verhoff MA, Hagemeyer TP, Müller KM. Arachnoid cyst with consecutive brain stem atrophy, hypoglossal nerve paresis and tongue atrophy. Pathologe 2001;22:266­9. 8. Singh S, Shankar RR, Singhi PD, Kumar L. Isolated hypoglossal nerve palsy in pyogenic meningitis. Indian Pediatr 1988;25:705­6. 9. Cheng VS, Schultz MD. Unilateral hypoglossal nerve atrophy as a late complication of radiation therapy ofhead and neck carcinoma: a report of four cases and a review of the literature on peripheral and cranial nerve damages after radiation therapy. Cancer 1975;35:1537­44. 10. Parano E, Giuffrida S, Restivo D, Saponara R, Greco F, Trifiletti RR. Reversible palsy of the hypoglossal nerve complicating infectious mononucleosis in a young child. Neuropediatrics 1998;29:46­7. 11. Wright GD, Lee KD. An isolated right hypoglossal nerve palsy in association with infectious mononucleosis. Postgrad Med J 1980;56:185­6. 12. Hadjikoutis S, Jayawant S, Stoodley N. Isolated hypoglossal nerve palsy in a 14­year­old girl. Eur J Paediatr Neurol 2002;6:225­8. 13. Felix JK, Schwartz RH, Myers GJ. Isolated hypoglossal nerve paralysis following influenza vaccination. Am J Dis Child 1976;130:82­3. 14. Thömke F, Lensch E, Ringel K, Hopf HC. Isolated cranial nerve palsies in multiple sclerosis. J Neurol Neurosurg Psychiatry 1997;63:682­5. 15. Giuffrida S, Lo Bartolo ML, Nicoletti A, Reggio E, Lo Fermo S, Restivo DA, et al. Isolated, unilateral, reversible palsy of the hypoglossal nerve. Eur J Neurol 2000;7:347­9.