A powerhead (50) of a power injector is disclosed that includes a syringe housing (110) that contains a capacitive fluid detector (112). The capacitive fluid detector (112) may be operable to detect fluid within a syringe (116) installed on the syringe housing (110). The output of the capacitive fluid detector (112) may be used to estimate the volume of fluid within the syringe (116). The capacitive fluid detector (112) may include a plurality of discrete capacitors (118a-118h) arranged serially along a longitudinal axis (120) of the syringe (116). Each of the plurality of capacitors (118a-118h) may be operable to produce an electric field extending into the syringe (116). Each of the plurality of capacitors (118a-118h) may be formed on a printed circuit board (130).
