Systems and methods are disclosed for identifying material aspirated during an ophthalmic procedure. Example systems comprise a first electrode and a second electrode positioned such that aspirated material flows between the first electrode and the second electrode and an alternating current impedance measuring component connected to the first electrode and the second electrode. The alternating current impedance measuring component measures the impedance of the aspirated material between the first electrode and the second electrode, and, based upon the measured impedance, the aspirated material can be identified.
