Jacob L. Jaremko MD, Presenter: Nothing to Disclose

Peter Joseph MacMahon MD, Abstract Co-Author: Nothing to Disclose

Martin Torriani MD, Abstract Co-Author: Nothing to Disclose

Vanessa Merker, Abstract Co-Author: Nothing to Disclose

Scott Randall Plotkin MD, Abstract Co-Author: Nothing to Disclose

Miriam Antoinette Bredella MD, Abstract Co-Author: Nothing to Disclose

To demonstrate incidental findings on whole body MRI (WBMRI) obtained in patients with neurofibromatosis type 1 and 2 (NF1 and NF2, respectively), and schwannomatosis.

Institutional review board approval and written informed consent were obtained for this prospective HIPAA-compliant study. 216 subjects (125 patients with NF1, 45 patients with NF2, and 46 patients with schwannomatosis, 130 women, 86 men; mean age, 41 years, range, 18-97 years) underwent WBMRI. WBMRI (1.5 T) was performed using coronal STIR (TR/TE: 4190/111 ms, TI: 150 ms) and T1-weighted (TR/TE: 454/10 ms) images; slice thickness 10 mm, field of view 500 mm, echo train 25, and 5 imaging stations providing cranio-caudal coverage with overlap between two adjacent stations of at least 40 mm. Total imaging time was approximately 40 minutes. Images were reviewed for the presence of incidental findings, unrelated to neurofibromatosis.

All WBMRI were of diagnostic quality. In 22 patients (10%), incidental findings involved the osseous structures. Seven patients (3%) had bone infarcts/avascular necrosis, six patients (3%) had stress/insufficiency fractures, and nine patients (4%) had benign bone lesions such as enchondromas or fibrous dysplasia. In one patient a mediastinal mass was detected that was found to represent lymphoma, and in one patient a liposarcoma was found. One patient had two pelvic dermoids, requiring surgery. Three patients (2%) had hepatic hemangiomatas that were confirmed by ultrasound and five patients (3%) had liver lesions, suggestive of hemangiomatas or cysts. Cases of unsuspected Richter’s hernia, bladder diverticulum, arcuate uterus, and renal atrophy were detected in one patient each.

Incidental findings in neurofibromatosis frequently involve the skeleton. Given the relatively high number of unsuspected osteonecrosis and stress fractures, close attention to the osseous structures on WBMRI is advised. In addition, knowledge of common incidental findings can help clinicians prepare patients who undergo WBMRI for potential unexpected findings.

Patients with neurofibromatosis have a high incidence of incidental findings affecting the skeleton. Radiologist should pay close attention to the bones when evaluating patients with neurofibromatosis.

Jaremko, J, MacMahon, P, Torriani, M, Merker, V, Plotkin, S, Bredella, M, Incidental Findings on Whole-Body MRI in Patients with Neurofibromatosis.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034359.html