Methods for treating a human patient having a subarachnoid hematoma, such as to prevent cerebral vasospasm or to reduce the severity of cerebral vasospasm in the patient, and associated devices, systems, and methods are disclosed herein. In a particular embodiment, a thrombolytic agent is introduced extravascularly into a subarachnoid region including the hematoma. A headset configured for hands-free delivery of transcranial ultrasound energy is connected to the patient and used to deliver ultrasound energy to the subarachnoid region to enhance the thrombolytic effect of the thrombolytic agent. The type and/or dosage of the thrombolytic agent can be selected based on the enhanced thrombolytic effect. For example, the enhanced thrombolytic effect can allow the therapeutically effective use of less aggressive thrombolytic agents and/or lower dosages of thrombolytic agents. In some cases, this can reduce the clinical probability of additional cerebral hemorrhage.