It has been rather generally accepted that colloid cysts of the third ventricle are derived from persisting remnants of the paraphysis2' 5 as first suggested by Sj6vall6 in 1909. The paraphysis is a variety of extraventricular choroid plexus found best developed in adult forms of the ganoid fishes and certain amphibia, but is present in the embryos of all vertebrates, including man. This struct...

A case of a neuroepithelial cyst of the cerebellar vermis is presented. The cyst contained a viscous fluid and a xanthogranulomatous nodule. The fluid showed high signal on T1- and low signal on T2-weighted MR images. The xanthogranuloma showed mixed intensities with partial contrast enhancement. The correlation of the cyst contents and MR signals is discussed.

A 26-year-old Brazil-born woman was hospitalized because of severe headaches that increased in severity when she moved her head. T2-fluid attenuated inversion recovery magnetic resonance imaging showed a cystic-like lesion in the right occipital horn of the lateral ventricle (Figure 1). Repeat magnetic resonance imaging of a ventral decubitus position showed that the free-floating cyst shifted ...

1. Mithal A. Paget’s disease in India. J Assoc Physicians India 2006;54: 521-2. 2. Raubenheimer PJ, Taylor AG, Soule SG. Paget’s disease complicated by hydrocephalus and syringomyelia. Br J Neurosurg 2002;16: 513-6. 3. Dohrmann PJ, Elrick WL. Dementia hydrocephalus in Paget’s disease: A case report. J Neurol Neurosurg Psychiatry 1982;45:835-7. 4. Martin BJ, Roberts MA, Turner JW. Normal pressur...

The dosimetry for radiocolloid therapy of cystic craniopharyngiomas is investigated. Analytical calculations based on the Loevinger and the Berger formulas for electrons and photons, respectively, are compared with Monte Carlo simulations. The role of the material of which the colloid introduced inside the craniopharyngioma is made of as well as that forming the cyst wall is analyzed. It is fou...

Saturated packed column and micromodel transport studies were conducted to gain insight on mechanisms of colloid retention and release under unfavorable attachment conditions. The initial deposition of colloids in porous media was found to be a strongly coupled process that depended on solution chemistry and pore space geometry. During steady state chemical conditions, colloid deposition was no...