Stephen F. Kralik
The first year of life is truly an amazing period of time in the life of a child. The brain is developing in order to allow for major changes in mobility, communication, and social interaction. Brain tumors in the first year of life are, thankfully, uncommon; however, these tumors present challenges for treating physicians. These tumors are more frequently supratentorial in location, and because the calvarium in the first year of life may allow for significant expansion, they are frequently large at time of presentation, which is problematic for surgeons. These tumors include potentially a wide range of pathologies, including congenital pathologies not encountered commonly, which may result in challenges for a pathologist. Furthermore, the large size may limit ability to determine location of origin, and frequent heterogeneous imaging appearance of these tumors, coupled with their relative infrequency, is problematic for radiologists in determining an exact diagnosis.
Previous research has indicated a correlation between reduced diffusion of water and increasing tumor cellularity and tumor grade, and apparent diffusion coefficient values have been shown previously to have diagnostic value in differentiating pediatric cerebellar tumors.1,2 Relatively little imaging research exists, however, regarding supratentorial brain tumors in the first year of life. We evaluated supratentorial brain tumors in the first year of life to determine if diffusion-weighted imaging could be helpful in suggesting whether a tumor was low-grade or high-grade, in order to provide a foundation for an imaging differential diagnosis. We used a manual ROI method of obtaining the minimum ADC value, which would simulate clinical practice, and we supported this analysis with a semi-automated method that allowed further demonstration of ADC characteristics of these tumors. Both methods demonstrated that increasing tumor grade correlated with decreasing ADC value of the tumor.