Adjustable volume syringe and method of use

Abstract

Adjustable volume syringes, and systems and methods for using the same, are disclosed. An adjustable volume syringe may include a delivery syringe, a reservoir syringe located at least in part within the delivery syringe, and a reservoir plunger located at least in part within the reservoir syringe. The delivery syringe may be configured to contain a first amount of a fluid and the reservoir syringe may be configured to contain a second amount of the fluid. An administration amount of the fluid may be determined at or prior to an administration time, and the amount of fluid in the delivery syringe may be adjusted to equal the administration amount by adding fluid from the reservoir syringe to the delivery syringe or by withdrawing fluid from the delivery syringe to into the reservoir syringe. The administration amount of fluid may be dispensed to a patient at the administration time.

What is claimed is: 
     
         1 . A method of using an adjustable volume syringe comprising a delivery syringe, a reservoir syringe located at least in part within the delivery syringe, and a reservoir plunger located at least in part within the reservoir syringe, the method comprising:
 storing a first amount of a fluid in the delivery syringe and a second amount of a fluid in the reservoir syringe;   determining an administration amount of the fluid to administer to a patient;   determining whether the administration amount of the fluid is greater than, less than or equal to the first amount of the fluid;   adjusting an amount of the fluid in the delivery syringe to equal the administration amount of the fluid; and   dispensing the administration amount of the fluid to the patient.   
     
     
         2 . The method of  claim 1 , wherein the fluid comprises a radionuclide. 
     
     
         3 . The method of  claim 2 , wherein the fluid comprises one of  18 F-deoxyglucose and  99m Tc or a  99m Tc containing compound. 
     
     
         4 . The method of  claim 2 , wherein determining the administration amount of the fluid comprises determining the administration amount of the fluid based on at least one of an expected administration time, an actual administration time, and a required radioactivity. 
     
     
         5 . The method of  claim 1 , wherein at least a portion of an interior surface of the reservoir syringe and at least a portion of an exterior surface of the reservoir plunger are threaded. 
     
     
         6 . The method of  claim 4 , wherein adjusting the amount of the fluid in the delivery syringe comprises rotating the reservoir plunger in a clockwise or counterclockwise direction relative to the reservoir syringe to draw fluid into the reservoir syringe from or expel fluid out of the reservoir syringe into the delivery syringe. 
     
     
         7 . The method of  claim 1 , wherein adjusting the amount of fluid in the delivery syringe comprises dispensing at least a portion of the second amount of the fluid from the reservoir syringe into the delivery syringe. 
     
     
         8 . The method of  claim 1 , wherein adjusting the amount of fluid in the delivery syringe comprises withdrawing at least a portion of the first amount of the fluid from the delivery syringe into the reservoir syringe. 
     
     
         9 . The method of  claim 1 , wherein adjusting the amount of fluid in the delivery syringe comprises adjusting the amount of fluid in the delivery syringe by a dispensing module. 
     
     
         10 . The method of  claim 9 , further comprising determining by a processor whether the administration amount of the fluid is greater than, less than, or equal to the first amount of the fluid. 
     
     
         11 . The method of  claim 10 , further comprises receiving by the dispensing module one or more signals from the processor to adjust the amount of fluid in the dispensing syringe to equal the administration amount of the fluid. 
     
     
         12 . The method of  claim 11 , wherein adjusting the amount of fluid in the dispensing syringe comprises dispensing at least a portion of the second amount of the fluid from the reservoir syringe into the delivery syringe or withdrawing at least a portion of the first amount of the fluid from the delivery syringe into the reservoir syringe. 
     
     
         13 . The method of  claim 10 , wherein dispensing the administration amount of the fluid to the patient is performed by the dispensing module when the first amount of the fluid is equal to the administration amount of the fluid. 
     
     
         14 . The method of  claim 10 , wherein determining the administration amount of the fluid comprises determining the administration amount of the fluid by the processor based on at least one of an expected administration time, an actual administration time, and a required radioactivity.