Primary CNS lymphomas
41 Primary CNS lymphomas CNS lymphomas may be primary or secondary: Primary CNS lymphomas (PCNSLs) are extra-nodal lymphomas that are confined to the brain or spinal cord at presentation. Most…
Mitochondrial encephalopathies
24 Mitochondrial encephalopathies The mitochondrial genome is a circular molecule of DNA (mtDNA) comprising 16 569 base pairs. Each mitochondrion contains 2–10 copies of the genome, which encodes 22 transfer…
Hyperkinetic movement disorders
30 Hyperkinetic movement disorders Several clinical conditions are characterized by the presence of excessive uncontrolled movements and are grouped as hyperkinetic movement disorders. These are chorea and ballismus, myoclonus, and…
Disorders that primarily affect white matter
5 Disorders that primarily affect white matter Inherited metabolic disorders that primarily affect white matter are occasionally encountered in children, and even more rarely in adults. A wide range of…
Hydrocephalus
4 Hydrocephalus Hydrocephalus means an increased volume of cerebrospinal fluid (CSF) in the cranial cavity. The term internal hydrocephalus implies an increased volume of CSF within the ventricular system, but…
Choroid plexus neoplasms
40 Choroid plexus neoplasms CHOROID PLEXUS NEOPLASMS The choroid plexus (CP) is a specialized epithelium that secretes cerebrospinal fluid (CSF) and is sited in the ventricles of the brain. Most…
Neoplasms that spread to the CNS
46 Neoplasms that spread to the CNS Primary neoplasms of the skull and spine may impinge upon the CNS, and (primary) neoplasms in other organs may metastasize to the CNS,…
Paraneoplastic disorders
47 Paraneoplastic disorders Patients with a primary neoplasm remote from the CNS may develop neurologic symptoms and signs as a consequence of: Spread of the neoplasm to the nervous system…
Classification and pathogenesis of neurodegenerative diseases
26 Classification and pathogenesis of neurodegenerative diseases The neurodegenerative diseases are characterized by progressive dysfunction and death of neurons. The degeneration often affects specific systems, implying some form of selective…
Rickettsial and mycoplasma infections
14 Rickettsial and mycoplasma infections RICKETTSIAE Although historically an important cause of human infection (epidemic typhus was responsible for over three million deaths in Russia between 1915 and 1925), rickettsiae…
