Patent ID: 7695435
Filing Date: 2010-04-13
Classification: A61B

Abstract:
1. A system for detecting a surgical implement retained within a surgically exposed body cavity, the system comprising, in combination: (1) means for transmitting a modulated radio frequency (RF) electromagnetic signal; (2) a tag adapted to be attached to a surgical implement insertable within a body cavity, and including: (a) receiving means for receiving said modulated RF electromagnetic signal and converting it into an electric signal said receiving means including at least one antenna and one capacitor with values chosen for resonating at said RF; (b) a diode detector for rectifying and demodulating of said electric signal; (c) output means including two electrodes adapted for impressing the modulated frequency electric signal on the internal tissue of the body cavity where said surgical implement is used; (d) an output capacitor coupled with said diode detector and said output means; and (e) an output resistor coupled with said output capacitor and said output means whose value equals to the resistance of the tissue across said output means; and (3) detecting means including: (a) reception means for receiving through conduction said electric signal impressed on the tissue by said electrodes including at least two conductive pads adapted for placing on the biological tissue; and (b) detector means connected to the reception means for sensing said electric signal.