Neurofibromatosis Type 1 and Arnold-Chiari Malformation

Abstract

Neurofibromatosis type 1 (NF-1) or von Recklinghausen disease is the most common neurocutaneous syndrome. It is characterized by the appearance of various cutaneous stigmata, neurological manifestations, and an increased susceptibility to develop tumors.1 Although it is frequently associated with a wide variety of central nervous system (CNS) dysplasias, the association with Arnold-Chiari malformation type I is unusual. A 60-year-old woman with a past history of systemic hypertension, hiatus hernia, and iron-deficiency anemia, was seen in our outpatient clinic for lesions on her neck that had been present the years and that caused discomfort due to friction. On physical examination of the skin, multiple soft fibromas were observed in the cervical region; however, a large number of hyperpigmented macules with a homogeneous, light brown color and welldefined borders were also observed, mainly on the trunk, though also at the root of the limbs, and 9 of them were over 15 mm in diameter, and there were also groups of hyperchromic macules between 2 and 10 mm in diameter in both axillas, clinically consistent with lentigo simplex (Crowe sign). The patient stated that those lesions had been present since birth, and that her father had similar spots. Based on these findings, the patient was diagnosed with NF-1 and was referred to the neurology and ophthalmology departments to exclude CNS and optic nerve involvement. Ophthalmologic examination was normal, with no evidence of Lisch nodules. The patient had no neurological symptoms and neurological examination revealed generalized, symmetrical muscle hyperreflexia but no other alterations. Cerebral magnetic resonance imaging (MRI) showed herniation of the cerebellar tonsils into the upper cervical canal, below the level of the Figure 1. Sagittal cerebral magnetic resonance image: the T 1-weighted image shows herniation of the cerebellar tonsils into the upper cervical canal, below the level of the occipital foramen, consistent with Arnold-Chiari malformation type I. neurofibromatosis type 1 and arnold-Chiari Malformation