Neuropediatrics 2011; 42(04): 159-162
DOI: 10.1055/s-0031-1285925
Short Communication
Georg Thieme Verlag KG Stuttgart · New York

The “Eye-of-the-Tiger” Sign may be Absent in the Early Stages of Classic Pantothenate Kinase Associated Neurodegeneration

L. Chiapparini
1  Department of Neuroradiology, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
M. Savoiardo
1  Department of Neuroradiology, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
S. D’Arrigo
2  Department of Child Neurology, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
C. Reale
3  Child Neuropsychiatry Unit, Policlinico Universitario S. Orsola-Malpighi, Bologna, Italy
,
G. Zorzi
2  Department of Child Neurology, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
F. Zibordi
2  Department of Child Neurology, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
D. M. Cordelli
4  Department of Molecular Neurogenetics, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
E. Franzoni
4  Department of Molecular Neurogenetics, IRCCS Neurological Institute Carlo Besta, Milano, Italy
,
B. Garavaglia
3  Child Neuropsychiatry Unit, Policlinico Universitario S. Orsola-Malpighi, Bologna, Italy
,
N. Nardocci
2  Department of Child Neurology, IRCCS Neurological Institute Carlo Besta, Milano, Italy
› Author Affiliations
Further Information

Publication History

received 23 June 2011

accepted 29 July 2011

Publication Date:
29 August 2011 (eFirst)

Abstract

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare disorder associated with brain iron accumulation. The brain MRI abnormality consists of T2 hypointensity in the globus pallidus with a small hyperintensity in its medial part, called the “eye-of-the-tiger” sign. We report on 2 patients affected by PKAN, in whom MRI examination did not demonstrate the “eye-of-the-tiger” sign in the early stages; the typical abnormalities were detected only in the following examinations. Case 1 is a 4-year-old boy first studied at age 2 years for psychomotor delay. The brain MRI was normal. In the following 2 years, the motor impairment progressed. The second brain MRI at age 4 years demonstrated the “eye-of-the-tiger” sign. Molecular analysis of the PANK2 gene revealed a missense mutation F228S in exon 2 in homozygosis. Case 2 is a 6-year-old boy first studied at age 2 years because of psychomotor delay. His brain MRI did not demonstrate abnormalities in the globus pallidus. In the following years spastic-dystonic tetraparesis became evident. A brain MRI at age 4 years demonstrated the “eye-of-the-tiger” sign. Molecular analysis of the PANK2 gene revealed a missense mutation in exon 5 (N501I). Our 2 cases demonstrate that the observation of a normal globus pallidus in the early stage of the disease does not exclude the diagnosis of classic PKAN.