Widening of the diploic space

Widening of the diploic space refers to expansion of the cancellous (spongy) bone between the inner and outer tables of the calvaria. The diploic space is the medullary cavity of the skull, and a location of normal physiologic hematopoiesis in adults. Thus, expansion of this structure most commonly occurs in the setting of chronically increased intramedullary hematopoiesis. The widened appearance is most commonly bilateral.

Causes

Most commonly caused by systemic pathologies such as:

• chronic hemolytic disorders: may be associated with vertical striations running in diploic space giving rise to the characteristic hair on end sign
  • sickle cell disease
  • thalassemia
  • iron deficiency anemia
  • other chronic severe anemias
• Paget disease (Tam o' Shanter sign)
• metabolic disorders
  • renal osteodystrophy
  • hyperparathyroidism
• overgrowth
  • microcephaly
  • acromegaly
• medication
  • phenytoin

Siehe auch:

• Tam O'Shanter Zeichen