MR imaging features in children with type 1 neurofibromatosis (NF1) : intra- and extracranial lesions

Background: Type 1 neurofibromatosis (NF1) may be manifested by a variety of changes in the central nervous system (CNS) and in other organs. The risk of malignancy is increased in these patients. The purpose of the study was to present the utility of magnetic resonance imaging (MRI) in the visualization of lesions and in monitoring of the disease and its therapy in children with NF1. Material/Methods: We analyzed retrospectively 128 MRI scans in 44 children diagnosed with NF1, treated in the Institute of Mother and Child in Warsaw. The analyzed group consisted of 19 boys and 25 girls, aged 1-24 years, mean age 10.8 yrs. MRI examinations were performed in the years 2004-2008 with a 1.5 T scanner. There were 76 brain scans and 52 examinations of other regions of the body. Results: Brain lesions were found on MRI in 27 children (64.2%); there were UBOs in 26/42 (62.2%) patients and optic nerves gliomas in 11/42 (26.2%) children. In 3 cases, evolution of UBOs was observed over the time. Extracranial lesions were visualized in 52 MR examinations in 20 children. Very extensive plexiform neurofibromas compressing abdominal and pelvic organs were observed, and 3 cases of spinal canal invasion, with spinal cord compression in one patient. Malignant lesions were found in 3 patients: 2 malignant peripheral nerve sheath tumors (MPNST) and 1 rhabdomyosarcoma (RMS). The MRI characteristics of intra- and extracranial lesions is presented. Conclusions: Children with NF1 require constant care in the specialized center with a multidisciplinary team and MRI equipment available. MR examination in the best imaging method in children with NF1, allowing both diagnosis and monitoring of the patients, especially evaluation of lesions suspicious of malignancy, as well as treatment planning.