Neurofibromatosis type 1: pathologic substrate of high-signal-intensity foci in the brain.
OBJECTIVE
To investigate a correlation between pathologic and radiologic findings with regard to the characteristic high-signal-intensity foci seen on long repetition time (TR) magnetic resonance (MR) images of the brain in patients with neurofibromatosis type 1 (NF-1).


METHODS
Three girls with NF-1 and abnormal hyperintensities on long TR images of the brain underwent pathologic examination at autopsy.


RESULTS
Two 10-year-old girls had classic, focal hyperintensities in the internal capsules and globus pallidus regions, which have been associated with NF-1. The third patient, a neonate, had diffuse hyperintensity of the supratentorial and infratentorial white matter on T2-weighted MR images. Findings at histopathologic examination revealed spongiotic change in the tissue sections that correspond to the high-signal-intensity foci demonstrated on T2-weighted images.


CONCLUSIONS
Hyperintense foci seen on T2-weighted MR images appear to correspond to pathologic findings of areas of vacuolar or spongiotic change. The resultant fluid-filled vacuoles explain the occurrence of high signal intensity demonstrated on T2-weighted images.
DiPaolo
D P
DP
Department of Radiology, Children's Hospital of Philadelphia, PA 19104, USA.
Zimmerman
R A
RA
Rorke
L B
LB
Zackai
E H
EH
Bilaniuk
L T
LT
Yachnis
A T
AT
D001921:Brain / Q000473:pathology*; D001932:Brain Neoplasms / Q000175:diagnosis / Q000473:pathology; D002648:Child; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D009456:Neurofibromatosis 1 / Q000175:diagnosis* / Q000473:pathology