Blood-brain barrier (BBB) disruption underlies the origin of many brain disorders. Measuring subtle BBB leakage of gadolinium-based contrast agents is commonly performed by a continuous and time-consuming dynamic MRI protocol. However, BBB leakage is subtle, for which discrete sampling at strategic time-points might be sufficient. This study explores the feasibility of the time-efficient interleaved protocol by applying it to brain tumor patients. We were able to measure high permeability in a craniopharyngioma and low permeability in a low-grade tumor and in healthy tissue. The time-efficient protocol is promising and will be further evaluated in more patients.