The role of apparent diffusion coefficient (ADC) value in the differentiation between the most common pediatric posterior fossa tumors

BackgroundDiffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) map provide information on MRI about the cellularity of the tumor and have an important role in the pre-operative differentiation of different tumor types.AimIs to evaluate the role of ADC value measurement in the differentiation between the most common pediatric posterior fossa tumors which include juvenile pilocytic astrocytoma, ependymoma and medulloblastoma.Patients & methodsThirty patients were retrospectively included in this study. They were referred from the Neurosurgery Department and all of them suspected to have posterior fossa SOL according to the contrast enhanced CT. All patients were subjected to conventional MRI followed by diffusion MR imaging and calculation of the ADC values.ResultsIn JPA (group 1, n = 14), ADC values ranged between 2.4 and 1.3 × 10−3 mm2/s, ependymoma (group 2, n = 9), ADC values ranged between 1 and 1.3 × 10−3 mm2/s and medulloblastoma (group 3, n = 7), ADC values ranged between 0.5 and 0.9 × 10−3 mm2/s. Statistically significant difference in ADC value was detected between group1, group 2 and group 3, while no statistically significant difference was detected between group 1 and group 2.ConclusionThe calculation of ADC value in the solid enhancing portion of a tumor is a simple and reliable technique for preoperative differentiation of the most common posterior fossa.