acquired tonsillar ectopia

Acquired tonsillar ectopia is usually thought of as a subgroup of cerebellar tonsillar ectopia in which downward displacement of the cerebellar tonsils is secondary to another well defined and distinct pathological process. This is to distinguish it from Chiari I malformations and low-lying tonsils.

The terminology of caudally displaced tonsils is discussed in the article on cerebellar tonsillar ectopia.

Causes

Causes of acquired tonsillar ectopia include:

• raised intracranial pressure
  • tonsillar herniation from trauma or tumor
  • pseudotumor cerebri (idiopathic intracranial hypertension)
• decreased intracranial pressure
  • spontaneous craniospinal hypotension (e.g. CSF leak)
  • CSF drainage or shunting (e.g. ventriculoperitoneal shunt)

Siehe auch:

• Chiari-Malformation Typ 1
• Tiefstand der Kleinhirntonsillen
• benigner Tiefstand der Kleinhirntonsillen

und weiter:

• Kleinhirntonsillen