Radiosurgical Neuromodulation Devices, Systems, and Methods for Treatment of Behavioral Disorders by External Application of Ionizing Radiation

Abstract

Radiosurgical techniques and systems treat behavioral disorders (such as depression, Obsessive-Compulsive Disorder (“OCD”), addiction, hyperphagia, and the like) by directing radiation from outside the patient toward a target tissue within the patient's brain, typically without imposing surgical trauma. The target will often be included in a neural circuit associated with the behavioral disorder. A cellularly sub-lethal dose of the radiation may be applied and the radiation can mitigate the behavioral disorder, obesity, or the like, by modulating the level of neural activity within the target and in associated tissues. Hypersensitive and/or hyperactive neuronal tissue may be targeted, with the radiation downwardly modulating hyperactive neuronal activity. By down-regulating the activity of a target that normally exerts negative feedback or a limiting effect on a relevant neural circuit, the activity of the circuit may be increased.

1 . A method of treating a psychiatric disorder or a neurological disorder of a patient, the psychiatric disorder or the neurological disorder of the patient associated with a level of neuronal activity in a neural circuit within a brain of the patient, the method comprising:
 transmitting a cellularly sub-lethal quantity of ionizing radiation from outside the patient into a target comprising at least a portion of the amygdala within the brain of the patient so as to alter the level of neuronal activity in the neural circuit such that the psychiatric disorder or the neurological disorder is mitigated, wherein the radiation is transmitted from a radiation source machine outside the patient, through a skull of the patient and into the brain of the patient along a plurality of beam paths directed from varying directions so as to intersect with the target.   
     
     
         2 . The method of  claim 1 , wherein the psychiatric disorder or the neurological disorder is obsessive-compulsive disorder. 
     
     
         3 . The method of  claim 1 , wherein the psychiatric disorder or the neurological disorder is associated with addiction. 
     
     
         4 . The method of  claim 1 , wherein the psychiatric disorder or the neurological disorder is associated with anxiety. 
     
     
         5 . The method of  claim 1 , wherein the psychiatric disorder or the neurological disorder is associated with depression. 
     
     
         6 . The method of  claim 1 , wherein the ionizing radiation is transmitted with a cross-sectional size of less than 5 mm. 
     
     
         7 . The method of  claim 6 , wherein the ionizing radiation is transmitted with a cross-sectional size of less than 3 mm. 
     
     
         8 . The method of  claim 1 , wherein the target is morphologically normal tissue. 
     
     
         9 . The method of  claim 1 , wherein the target for the ionizing radiation comprising at least the portion of the amygdala has a volume of less than 0.5 cc. 
     
     
         10 . The method of  claim 1 , wherein an activity of the amygdala is decreased by the transmission of the quantity of ionizing radiation. 
     
     
         11 . A system for treating a psychiatric disorder or a neurological disorder of a patient, the psychiatric disorder or the neurological disorder of the patient associated with a level of neuronal activity in a neural circuit within a brain of the patient, the system comprising:
 a source for transmitting ionizing radiation; and   a processing system coupled to the source, the processing system configured to effect transmission of a plurality of beams of the radiation from the source into a target comprising at least a portion of the amygdala within the brain of the patient so that the radiation within the target is a sub-lethal quantity and is sufficient to alter the level of neuronal activity in the neural circuit such that the psychiatric disorder or the neurological disorder is mitigated.   
     
     
         12 . The system of  claim 11 , wherein the psychiatric disorder or the neurological disorder is obsessive-compulsive disorder. 
     
     
         13 . The system of  claim 11 , wherein the psychiatric disorder or the neurological disorder is associated with addiction. 
     
     
         14 . The system of  claim 11 , wherein the psychiatric disorder or the neurological disorder is associated with anxiety. 
     
     
         15 . The system of  claim 11 , wherein the psychiatric disorder or the neurological disorder is associated with depression. 
     
     
         16 . The system of  claim 11 , wherein the ionizing radiation is transmitted with a cross-sectional size of less than 5 mm. 
     
     
         17 . The system of  claim 16 , wherein the ionizing radiation is transmitted with a cross-sectional size of less than 3 mm. 
     
     
         18 . The system of  claim 11 , wherein the target is morphologically normal tissue. 
     
     
         19 . The system of  claim 11 , wherein the target for the ionizing radiation has a volume of less than 0.5 cc. 
     
     
         20 . The system of  claim 11 , wherein the ionizing radiation is configured to decrease an activity of the amygdala.