Brief Answer:
Raised intracranial pressure must be excluded.

Detailed Answer:
I read your question carefully and I understand your concern.

Usually the inner surface of the skull is smooth. Copper beaten skull is the term used for a finding where it is not smooth but has inner markings, which correspond to the form of the brain gyri, the ridges on the outer surface of the brain, which have been compressing this inner surface of the skull creating those markings.

Now the causes can be several, any process which results in increased pressure inside the skull could cause that appearance, such as a tumor, accumulation of fluid in the brain due to blockage in its circulation from an infection or a hemorrhage, a condition called craniosynostosis (premature closure of the cranial sutures in childhood).

There is also a percentage of cases where it is seen in completely normal patients, so it could be nothing to worry about, perhaps if you said something more on your symptoms and their evolution in time, as well as past conditions I might be able to say something more.

If all you've had is a xray, further tests are necessary to search for those raised pressure causes, ideally a MRI, but a cat scan of the head with contrast is useful as well if MRI is not available.

I remain at your disposal for further questions, possibly with the additional info I mentioned above.

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