Ophthalmic injection device using shape memory alloy
View Patent ↗An ophthalmic injection device has a dispensing chamber housing, a needle fluidly coupled to a dispensing chamber, a power source for providing current to the dispensing chamber housing, a controller for controlling the power source, and a housing at least partially enclosing the dispensing chamber housing, the power source, and the controller. The dispensing chamber housing is made of a shape memory alloy and has an inner surface defining a dispensing chamber for receiving a quantity of a substance. The controller directs a first current to the dispensing chamber housing to heat the substance contained in the dispensing chamber and a second current to the dispensing chamber housing to alter the shape of the dispensing chamber housing to deliver the substance.
1. An ophthalmic injection device comprising:
a dispensing chamber housing with a wall made of a shape memory alloy and having an inner surface and an outer surface, the inner surface defining a dispensing chamber for holding a quantity of a substance;
a needle fluidly coupled to the dispensing chamber;
a power source for providing current to the dispensing chamber housing;
a controller for controlling the power source; and
a housing at least partially enclosing the dispensing chamber housing, the power source and the controller;
wherein the controller directs a first current to the dispensing chamber housing to heat the substance contained in the dispensing chamber and a second current to the dispensing chamber housing to alter the shape of the dispensing chamber housing to deliver the substance.
2. The system of claim 1 wherein the device further comprises:
a thermal sensor located near the dispensing chamber housing, the thermal sensor for measuring a temperature.
3. The device of claim 2 further comprising:
an interface connecting the thermal sensor to the controller.
4. The device of claim 2 wherein the controller uses the measured temperature to control the first current directed to the dispensing chamber housing.
5. The device of claim 2 wherein the controller uses the measured temperature to control the second current directed to the dispensing chamber housing.
6. The device of claim 1 wherein the controller controls the second current to control an amount of the substance that is delivered.
7. The device of claim 1 wherein the controller controls the second current to control a rate at which the substance is delivered.
8. The device of claim 1 wherein the power source is a rechargeable battery.
9. The device of claim 1 wherein the substance is a drug for treating a condition of the eye.
10. The device of claim 1 wherein the device further comprises:
an indicator located on the housing, the indicator for providing information about a status of substance delivery.