Patent ID: 8668665

Claim:
An aspiration system comprising: an aspiration line having distal and proximal ends and an aspiration port defined in the distal end; a fluid transport device operatively coupled to the proximal end of the aspiration line; a variable flow restrictor, the variable flow restrictor operatively coupled to the aspiration line in between the fluid transport device and the aspiration port; a first pressure/vacuum sensor operatively coupled to the aspiration line between the port and the variable flow restrictor; a second pressure/vacuum sensor configured to measure both pressure and vacuum and operatively coupled to the aspiration line between the variable flow restrictor and the fluid transport device, wherein at least one of the first pressure/vacuum sensor and the second pressure/vacuum sensor is at least partially disposed within a drainage cassette; and a computer program product that includes a computer-usable medium having a sequence of instructions which, when executed by a processor, causes said processor to execute a process to measure a differential value equal to a difference in a first pressure/vacuum of the first pressure/vacuum sensor and a second pressure/vacuum of the second pressure/vacuum sensor.