ABSTRACT
The blood-brain barrier (BBB) isolates the brain from the general circulation of the body and thus protects it from harmful xenobiotics. This isolation, however, renders the pharmacological treatment of the brain most difficult, as most drugs cannot enter the brain owing to the existence of the BBB. BBB research addresses multiple clinical questions (Table 26.1), which together utilize powerful techniques for the evaluation of BBB functions in patients (Table 26.2). Answering these questions will have practical clinical benefits that justify these efforts (Table 26.3).
