Pressure control in phacoemulsification system
View Patent ↗A surgical system comprises a pressurized irrigation fluid source; an irrigation line fluidly coupled to the pressurized irrigation fluid source; a hand piece fluidly coupled to the irrigation line; an irrigation pressure sensor located at or along the pressurized irrigation fluid source or irrigation line; and a controller for controlling the pressurized irrigation fluid source. The controller controls the pressurized irrigation fluid source based on a reading from the irrigation pressure sensor and an estimated flow value modified by a compensation factor.
1. A method of controlling a surgical system having a fluid flow path, the method comprising:
receiving a pressure reading from an irrigation pressure sensor located along the fluid flow path;
calculating an estimated fluid flow through the surgical system;
modifying the estimated fluid flow with a compensation factor; and
controlling a pressurized irrigation fluid source based on the pressure reading and the estimated fluid flow as modified by the compensation factor, the compensation factor based on compression of an irrigation sleeve that restricts flow of irrigation fluid.
2. The method of claim 1 wherein the compensation factor is further based on incision leakage.
3. The method of claim 1 further comprising:
receiving a desired intraocular pressure value; and
controlling the pressurized irrigation fluid source so as to maintain the desired intraocular pressure value.
4. The method of claim 1 further comprising:
receiving a desired intraocular pressure range; and
controlling the pressurized irrigation fluid source so as to maintain the desired intraocular pressure range.
5. The method of claim 1 further comprising:
calculating an intraocular pressure of an eye based on the reading from the irrigation pressure sensor.
6. The method of claim 1 further comprising:
calculating an intraocular pressure of an eye based on the estimated flow value modified by the compensation factor.
7. The method of claim 1 wherein calculating the estimated flow value further comprises:
receiving a reading from an aspiration pressure sensor located along the fluid path, a pump vacuum pressure achievable by the aspiration pump, and an impedance of the aspiration pump.
8. The method of claim 1 wherein calculating the estimated flow value further comprises:
receiving a reading from the irrigation pressure sensor, a reading from a source pressure sensor, and an impedance of the fluid flow path between the source pressure sensor and the irrigation pressure sensor; and
estimating flow based on a difference between the reading from the irrigation pressure sensor and the source pressure sensor.
9. The method of claim 1 wherein the compensation factor is based on a needle and sleeve selected for a procedure.
10. The method of claim 1 further comprising:
receiving the compensation factor from a user.
11. The method of claim 1 further comprising:
receiving needle and sleeve information; and
using the needle and sleeve information to select or calculate the compensation factor.
12. The method of claim 11 wherein selecting or calculating the compensation factor is based on fluid flow characteristics of a needle and sleeve combination.
13. The method of claim 1 further comprising:
receiving a pressure reading from an aspiration pressure sensor located along the fluid path; and
using the pressure reading from the aspiration pressure sensor to determine if an occlusion is present or if an occlusion break occurs.
14. The method of claim 13 wherein controlling the pressurized irrigation fluid source further comprises accommodating for changes in fluid flow that result from the occlusion or the occlusion break.
15. The method of claim 1 further comprising:
receiving a pressure reading from the irrigation pressure sensor; and
using the pressure reading from the irrigation pressure sensor to determine if an occlusion is present or if an occlusion break occurs.
16. The method of claim 15 wherein controlling the pressurized irrigation fluid source further comprises accommodating for changes in fluid flow that result from the occlusion or the occlusion break.