"Moya" than meets the eye: neurofibromatosis type 1 associated with Moyamoya syndrome

Tan RMR, Chng SM, Seow WT, Wong J, Lim CCT
Correspondence: Dr Lim CC Tchoyoson, tchoyoson_lim@nni.com.sg

ABSTRACT
Moyamoya syndrome (MMS) is an uncommon association of neurofibromatosis type 1 (NF1). We describe a seven-year-old chinese girl with NF1 and unilateral MMS with multiple hyperintensities on T2-weighted magnetic resonance (MR) images. The ischaemic lesions in the ipsilateral white matter were hypointense on fluid attenuated inversion recovery (FLAIR) MR images, in contrast to the hyperintense "unidentified bright objects" (UBOs) of NF1. Neuroradiologists should be aware of associated MMS in NF1 patients, and distinguish the effects of ischaemia from UBOs, especially on FLAIR MR imaging.

Keywords: cerebral ischaemia, cerebrovascular disease, magnetic resonance imaging, Moyamoya syndrome, neurofibromatosis, phacomatoses
Singapore Med J 2008; 49(4): e107-e109