Hysteroscopic Tissue Removal Systems: A Randomized In Vitro Comparison.

STUDY OBJECTIVE: To compare polyp resection time and myoma resection rate using 2 hysteroscopic tissue removal systems.

DESIGN: Prospective randomized in vitro trial (Canadian Task Force classification I).

SETTING: Clinical skills laboratory of a non-university teaching hospital.

SAMPLES: Polyp surrogate and myoma tissue.

INTERVENTIONS: Hysteroscopic tissue removal with the TRUCLEAR system, using the TRUCLEAR INCISOR 2.9 (TI), TRUCLEAR INCISOR Plus (TIP), or TRUCLEAR ULTRA Plus (TUP) device, and the MyoSure system, using the MyoSure Lite (ML), MyoSure Classic (MC), or MyoSure XL (MXL) device.

MEASUREMENTS AND MAIN RESULTS: Forty-two fragments of umbilical cord weighing 5 g, as a surrogate for polyps, were randomly allocated to 4 types of devices (TI, TIP, ML, and MC). Three consecutive fragments were removed using a single device. In addition, 18 pieces of myoma tissue were divided into 2 equal parts and randomly allocated to 2 types of devices (TUP and MXL). A new device was used for each fragment. Each type of device was tested at 2 vacuum settings. When removing 1 polyp, the TIP (median time, 2:33 minutes [interquartile range (IQR), 1:32-3:27 minutes]), the MC (median time, 3:15 minutes [IQR, 2:42-3:42 minutes]), and the ML (median time, 3:00 minutes [IQR, 2:16-3:25 minutes]) performed significantly faster than the TI (median time, 14:09 minutes [IQR, 13:44-14:36 minutes]), by 84%, 78%, and 82% respectively (p < .001). The TIP performed 80% faster than the TI (median time, 2:27 minutes [IQR, 1:45-2:46 minutes] vs 10:37 minutes [IQR, 8:38-13:44 minutes]; p < .001) when removing a second polyp. For removal of a third polyp, the TIP performed significantly faster (median time, 2:22 minutes [IQR, 1:32-3:07 minutes]) than the TI (median time, 8:35 minutes [IQR, 7:37-9:03 minutes]) and the ML (median time, 10:02 minutes [IQR, 9:51-10:18 minutes]), by 74% and 78%, respectively (p < .001). The performance of the ML decreased (p < .001) during removal of 3 consecutive tissue samples. For myoma tissue, the estimated mean resection rate of the TUP (2.96 g/min [95% confidence interval (CI), 2.32-3.77 g/min]) was 24% (95% CI 0.2%-52.4%) higher than the mean resection rate of the MXL (2.39 g/min [95% CI 1.87-3.05 g/min]; p = .048). The resection rate of the MXL adjusted for vacuum setting declined by 3% per unit increase in myoma volume (95% CI, -0.6% to -5.7%; p = .02). For the TUP, no linear association was found (0.4%; 95% CI, -2.1% to 3.0%; p = .72).

CONCLUSION: In vitro comparison of the removal of surrogate polyps showed that although the larger TIP, MC, and ML devices were significantly faster than the TI for removal of 1 polyp, only the TIP was consistently faster than the TI for consecutive removal of polyps. The performance of the ML decreased significantly during removal of 3 consecutive tissue samples, making it slower than the TIP with a similar window size in the third run. For removal of myoma tissue, the resection rate of the TUP was significantly higher than that of the MXL, and the resection rate of the MXL decreased with increasing myoma volume. In vitro testing can provide useful information on the time and rate of hysteroscopic tissue removal.