If surgeons remove part of your brain, how do they fill up the space?

Dear Cecil: When a portion of the brain is removed, as in the case of Mr. Brady, Ron Reagan’s press secretary, what do surgeons use to fill the space? Is it stuffed with cotton, gelatin, or left vacant? Mr. P., Baltimore

Cecil replies:

In operating on a traumatized brain, one of the main objectives of the neurosurgeon is to relieve the pressure within the skull that may be caused by foreign objects, blood, or scar tissue. The absence of pressure is not considered a problem worth worrying about, especially in light of the fact that introducing foreign matter would greatly increase the chance of infection. When a portion of the brain is removed, the vacated space is occupied by the brain’s natural juices. As for Mr. Brady, his physician refuses to discuss the particulars of his patient’s skull, but he assures me that he agrees with the foregoing in principle. It’s a safe bet, in other words, that Brady does not have cotton in his head. If he did, he would certainly have been transferred to the budget office by now.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.