Particulate matter generated during monopolar and bipolar hysteroscopic human uterine tissue vaporization

To characterize the insoluble particulate matter generated during hysteroscopic monopolar and bipolar electrosurgery.

In vitro comparative study (Canadian Task Force Classification II-1).

Teaching hospital.

Eight patients undergoing hysterectomy with benign indications.

Tissue blocks were divided, and 1g of tissue was vaporized using a monopolar and a bipolar vaporizing electrode.

The particles were examined at light microscopy to study their morphologic features. Particle analysis was carried out using a laser diffraction particle analyser. Monopolar uterine tissue vaporization generated particles of a smaller median diameter than did bipolar vaporization (0.13 microm and 0.25 microm, respectively). The distribution by particle surface area in both instruments seems to be complex, with peaks at 0.35 and 4.0 microm for monopolar-generated particles and 0.5 and 5.0 microm for bipolar-generated particles. Another smaller peak with larger particles produced by both instruments was identified at 30 microm. During monopolar uterine tissue vaporization, 9.96% of particles generated were smaller than 5 microm, whereas during bipolar vaporization, 3.81% of particles were smaller than 5 microm (p = .01).

Particulate matter generated during hysteroscopic electrosurgical vaporization using monopolar and bipolar instruments is heterodisperse and complex in shape. Monopolar vaporization results in particles of a smaller median diameter compared with bipolar vaporization. Both instruments generate 2 distinct populations of particles by surface area. The distribution of particles by volume during hysteroscopic electrosurgery is complex.