Methods and apparatuses are provided for initiating stroke treatment in the field and/or during the transport of the patient to a care facility. The capability is provided to adjust automatically to the individual therapeutic window for each single patient, which is crucial because of the significant differences in skull morphology between humans of different age, gender and race. Further, the methods and apparatuses are based on the use of non-invasive application of ultrasound, as well as the non-invasive application of ultrasound in combination with an acoustically active agent, such as microbubbles, where stable cavitation of the microbubbles caused by the ultrasound may be relied upon as an underlying mechanism for both the therapeutic application as well as its control.