Magnetic resonance imaging of normal and abnormal brain development.

Magnetic resonance imaging (MRI) improves our ability to assess brain development and to detect anomalies of brain formation. MRI allows the assessment of brain development by analysis of the effects of myelination on the T1 and T2 relaxation times of the pediatric brain. This article discusses specific imaging strategies and the normal progression of signal intensity changes.

Pediatric brain tumors.

The central nervous system is the second most common location for neoplasms in the pediatric age group. In this article, the characteristic imaging findings of the various supratentorial and infratentorial brain tumors are described.

Advances in diagnostic techniques of pituitary tumors and prolactinomas.

The main advances in the diagnostic evaluation of pituitary tumors and prolactinomas have been in the areas of improved magnetic resonance techniques and in the use of inferior petrosal sinus sampling. New dynamic techniques of rapid acquisition magnetic resonance imaging during bolus contrast infusion have improved the sensitivity for the diagnosis of the small microadenoma. The development of three-dimensional volume imaging has also led to a further improvement in sensitivity to small lesions of the sella.

MR imaging of rhombencephalosynapsis: report of three cases and review of the literature.

We describe the clinical and MR findings in three cases of rhombencephalosynapsis, a rare congenital malformation of the posterior fossa consisting of vermian agenesis or severe hypogenesis, fusion of the cerebellar hemispheres, and apposition or fusion of the dentate nuclei. Associated anomalies include hydrocephalus, fusion of the inferior colliculi, deficiency or absence of the septum pellucidum, and hypoplasia of the anterior commissure. Fourteen previous cases of rhombencephalosynapsis have been reported including Obersteiner's first report in 1914.