An ultrasound transducer assembly is connectable to an ultrasound system and comprises one or more ultrasound transducer elements supported by a cap. The ultrasound transducer elements are operable to direct ultrasound energy toward brain tissue of a subject and/or to receive echo ultrasound energy when the ultrasound transducer assembly is mounted on the head of the subject. Some embodiments include a fillable jacket coupled to the inner surface of the cap and in acoustic contact with the one or more transducer elements.