Treatment of subarachnoid hematoma using sonothrombolysis and associated devices, systems and methods

Abstract

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.

1 - 27 . (canceled) 
     
     
         28 . A system for treating a human patient having basal cisterns and a basal subarachnoid region encompassing the basal cisterns, the system comprising:
 a headset including ultrasound transducers positioned to direct ultrasound energy evenly throughout the basal subarachnoid region; and   a controller operably connected to the headset, wherein the controller is configured to control delivery of ultrasound energy to the basal subarachnoid region via the ultrasound transducers to enhance a thrombolytic effect of extravascular thrombolytic agent at the basal subarachnoid region.   
     
     
         29 . The system of  claim 28  wherein the controller is configured to control an intensity at which ultrasound energy is delivered to the basal subarachnoid region via the ultrasound transducers to enhance the thrombolytic effect. 
     
     
         30 . The system of  claim 28  wherein the controller is configured to control a frequency at which ultrasound energy is delivered to the basal subarachnoid region via the ultrasound transducers to enhance the thrombolytic effect. 
     
     
         31 . The system of  claim 28  wherein:
 the headset includes a transducer assembly carrying at least some of the ultrasound transducers; and 
 the transducer assembly is shaped to increase delivery of ultrasound energy from the ultrasound transducers to a peripheral portion of the basal subarachnoid region. 
 
     
     
         32 . The system of  claim 31  wherein the transducer assembly carries at least some of the ultrasound transducers in a convex arrangement. 
     
     
         33 . The system of  claim 28  wherein a given one of the ultrasound transducers is shaped to increase delivery of ultrasound energy from the given one of the ultrasound transducer to a peripheral portion of the basal subarachnoid region. 
     
     
         34 . The system of  claim 33  wherein the given one of the ultrasound transducers is convex. 
     
     
         35 . The system of  claim 28  wherein the headset is configured to detect blood-flow velocity in one or more of the patient's intracranial arteries. 
     
     
         36 . The system of  claim 28  wherein the controller is configured to control delivery of ultrasound energy from the headset to the basal subarachnoid region automatically at least partially in response to blood-flow velocity in one or more of the patient's intracranial arteries. 
     
     
         37 . The system of  claim 28 , further comprising a metering device operably connected to the basal subarachnoid region and operably connected to the controller, wherein the controller is configured to control delivery of thrombolytic agent to the basal subarachnoid region via the metering device. 
     
     
         38 . The system of  claim 37  wherein the controller is configured to control delivery of thrombolytic agent to the basal subarachnoid region via the metering device automatically at least partially in response to blood-flow velocity in one or more of the patient's intracranial arteries. 
     
     
         39 . A system for treating a human patient having a parenchyma and basal cisterns, the system comprising:
 a headset including ultrasound transducers positioned to direct ultrasound energy to the basal cisterns preferentially relative to the parenchyma; and   a controller operably connected to the headset, wherein the controller is configured to control delivery of ultrasound energy to the basal cisterns via the ultrasound transducers to enhance a thrombolytic effect of extravascular thrombolytic agent at the basal cisterns.   
     
     
         40 . The system of  claim 39  wherein the ultrasound transducers are positioned to direct ultrasound energy evenly throughout the basal cisterns. 
     
     
         41 . The system of  claim 39 , further comprising a user interface operably connected to the controller, wherein:
 the controller is configured to receive information about the patient via the user interface; and   the controller is configured to control delivery of ultrasound energy from the headset to the basal cisterns automatically at least partially in response to the information.   
     
     
         42 . The system of  claim 41  wherein the controller is configured to control an intensity at which the ultrasound energy is delivered to the basal cisterns automatically at least partially in response to the information. 
     
     
         43 . The system of  claim 41  wherein the controller is configured to control a frequency at which the ultrasound energy is delivered to the basal cisterns automatically at least partially in response to the information. 
     
     
         44 . The system of  claim 41  wherein:
 the patient has a ruptured intracranial aneurysm; and 
 the information includes an elapsed time since the intracranial aneurysm ruptured. 
 
     
     
         45 . The system of  claim 39 , further comprising:
 a user interface operably connected to the controller; and   a metering device operably connected to the basal cisterns and operably connected to the controller,   wherein—
 the controller is configured to receive information about the patient via the user interface, and 
 the controller is configured to control delivery of thrombolytic agent to the basal cisterns via the metering device automatically at least partially in response to the information. 
   
     
     
         46 . The system of  claim 45  wherein the controller is configured to control delivery of thrombolytic agent to the basal cisterns via the metering device automatically at least partially in response to blood-flow velocity in one or more of the patient's intracranial arteries. 
     
     
         47 . The system of  claim 45  wherein:
 the patient has a ruptured intracranial aneurysm; and 
 the information includes an elapsed time since the intracranial aneurysm ruptured.