Mems device and method for delivery of therapeutic agents

Abstract

Embodiments of an implantable device for delivering a therapeutic agent to a patient include a reservoir configured to contain a liquid comprising the therapeutic agent, a cannula in fluid communication with the reservoir, and means for forcing fluid from the reservoir into the cannula. Circuitry for controlling the means for forcing fluid from the reservoir into the cannula may be included.

1 . An implantable device for delivering a therapeutic agent to a patient, the device comprising:
 a reservoir for a liquid;   a cannula in fluid communication with the reservoir, the cannula having an outlet configured for fluid communication with the patient;   means for forcing fluid from the reservoir through the cannula; and   wirelessly operable circuitry for operating the forcing means.   
     
     
         2 . The device of  claim 1  wherein the forcing means comprises a pair of electrolysis electrodes. 
     
     
         3 . The device of  claim 1  further comprising a wirelessly chargeable battery for powering the circuitry. 
     
     
         4 . The device of  claim 1  wherein the circuitry controls dosage and release. 
     
     
         5 . The device of  claim 1  further comprising sensors for feedback control. 
     
     
         6 . The device of  claim 1  wherein the cannula is parylene. 
     
     
         7 . The device of  claim 1 , further comprising a valve for maintaining a constant flow rate through the cannula independent of pressure applied to the device. 
     
     
         8 . The device of  claim 6 , wherein the valve is at the end of the cannula. 
     
     
         9 . A method of delivering a therapeutic agent to a patient from a pump implanted in the patient, the pump comprising a reservoir, a cannula, and wirelessly operable circuitry, the method comprising the steps of:
 pumping a therapeutic liquid to a body site from the reservoir through the cannula; and   using an external source, sending wireless signals to the circuitry to operate the pump.   
     
     
         10 . The method of  claim 9  wherein pump further comprises a pair of electrolysis electrodes, the operating step comprising energizing the electrodes to cause creation of a gas that forces the liquid from the reservoir through the cannula, thereby delivering the liquid to the patient. 
     
     
         11 . The method of  claim 9  wherein the circuitry comprises a battery and further comprising the step of using the external source to wirelessly charge the battery. 
     
     
         12 . The method of  claim 9 , wherein the pump further comprises a valve for maintaining a constant flow rate through the cannula independent of pressure applied to the device and further comprising the step of maintaining a constant flow of liquid through the cannula independent of the pressure applied to the pump.