Apparent diffusion coefficients in evaluation of pediatric brain tumors.
BACKGROUND
MRI, which has high sensitivity in brain tumor detection, cannot reliably determine tumor grading or histology. Diffusion-weighted imaging and apparent diffusion coefficients (ADCs) provide information of tumor cellularity that can correlate with grading.


OBJECTIVE
To investigate ADCs in differentiation low-grade from high-grade pediatric brain tumors.


METHODS
Preoperative MRI, DWI, and ADC images of pediatric patients with pathologically proven brain tumors were retrospectively reviewed at a university hospital in two-year periods and classified into low-grade and high-grade categories. Regions of interest were placed manually at the center and periphery of the solid tumor regions, then ADC values were calculated at "b" values = 0, 1000 sec/mm2.


RESULTS
The ADC values were calculated in 15 patients, which included 12 males and three females with an age range from three to 14 years. Seven and eight were with low- and high-grade tumors respectively. The ADC values of low-grade tumors were markedly higher than those of high-grade tumors with statistically significant differences by all methods of measurements at the central peripheral, and average areas on Man-Whitney U test, with p-values of 0.037, 0.009, and 0.021, respectively.


CONCLUSIONS
MRI with ADCs for preoperative pediatric tumor evaluation may be useful for predicting tendency of tumor grading and surgical planning.
Division of Neuroradiology, Department of Radiology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. lojana.tun@mahidol.ac.th
Lojana
L
Tuntiyatorn
Bordin
B
Nantawas
Nongnuch
N
Sirachainan
Nopadol
N
Larbcharoensub
Anannit
A
Visudtibhan
Suradej
S
Hongeng
D000293:Adolescent; D001932:Brain Neoplasms / Q000473:pathology*; D002528:Cerebellar Neoplasms / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008297:Male