Bilateral thinning of the parietal bones

Dr Henry Knipe et al.

Bilateral thinning of the parietal bones, also known as biparietal osteodystrophy, is an uncommon, slowly progressive acquired disease of middle-aged people with slight female predilection. It is typically an incidental finding. 


The etiology is unknown but is thought to be an age-related process due to osteoporosis.

Microscopic appearance

On histologic examination, there is a lack of osteoclasts.

Radiographic features

Nuclear medicine

Bone scan usually shows well defined areas of photopenia, which further supports the osteoporotic etiology of this process.

Treatment and prognosis

In severe cases where brain is exposed to atmospheric pressure, cranioplasty may be indicated.

Article information

rID: 37523
Tag: skull
Synonyms or Alternate Spellings:
  • Parietal thinning
  • Biparietal osteodystrophy
  • Bilateral parietal thinning

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Cases and figures

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