Hyperostosis of the Skull

This patient has an olfactory groove meningioma extending into the roof of the nasal cavity. Typical of meningioma, hyperostosis of the skull may imply invasion (this point is controversial).
The differential diagnosis for hyperostosis of the skull depends on whether it is focal or diffuse.
Diffuse:
Paget’s disease of bone
metastatic disease, especial prostate carcinoma
chronic, severe anemia
hyperparathyroidism
acromegaly
osteopetrosis
hyperostosis frontalis interna
long term dilantin administration
genetic diseases (rare)
Camurati-Engelmann’s disease
frontometaphyseal dysplasia
craniodiaphysial dysplasia
Focal:
meningioma
fibrous dysplasia
Paget’s disease of bone
metastatic disease, especial prostate carcinoma
esthesioneuroblastoma - only rarely demonstrates hyperostosis.
References:
1. Pieper, D “Hyperostosis Associated with Meningioma of the Cranial Base: Secondary Changes or Tumor Invasion.” Neurosurgery. 44(4):742-746, April 1999.
2. Primer of Diagnostic Imaging by Weissleder
Credit: Dr Frank Gaillard
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