Ultrasonic cleaning is effective in removing carbonized clots and tissue from the insulation‐tipped diathermic knife‐2

Objectives

Since carbonized clots and tissue (debris) tend to adhere firmly to the tip of the endoscopic submucosal dissection (ESD) knife as the procedure proceeds, manual removing the firm debris is often challenging and time‐consuming. Recently, effective ultrasonic cleaning for other medical devices has been reported. The aim of the present study was to clarify whether ultrasonic cleaning is effective in removing the debris on the insulation‐tipped diathermic (IT) knife‐2.

Methods

This study was an ex‐vivo experimental randomized study. A total of 40 IT knife‐2 knives with debris on their tip surfaces were prepared and randomly assigned to two groups (Group A and Group B). The knives in Group A were cleaned using the conventional scrubbing method for 30 s (conventional cleaning method), while those in Group B were cleaned using a combined method of scrubbing for 20 s and ultrasonic cleaning for 10 s (combined ultrasonic cleaning method). The tip electrode of the knife after cleaning was photographed under a microscope (40x). The 40 images of the knives were evaluated by independent three endoscopists and two clinical engineers using the five‐step evaluation criteria ranging from cleaning score 1 (dirty) to 5 (clean).

Results

The mean cleaning score of 3.78 (range: 2.33–4.67) in Group B was significantly higher than that of 1.68 (range: 1.00–2.83) in Group A.

Conclusions

The combined ultrasonic cleaning method could remove debris adhering to the IT knife‐2 more effectively than the conventional cleaning method. Ultrasonic cleaning may be applied for real‐world ESD.

Efficacy of forced coagulation with low high-frequency power setting during endoscopic submucosal dissection

AIM

To investigated the hemostatic ability of the S and F1-10 methods in clinical and ex vivo studies.

METHODS

The hemostatic abilities of the two methods were analyzed retrospectively in all six gastric endoscopic submucosal dissection cases. The treated vessel diameter, compressed vessel frequency, and bleeding frequency after cutting the vessels were noted by the recorded videos. The coagulation mechanism of the two power settings was evaluated using the data recording program and histological examination on macro- and microscopic levels in the ex vivo experiments using porcine tissues.

RESULTS

F1-10 method showed a significantly better hemostatic ability for vessels ≥ 2 mm in diameter and a trend of overall better coagulation effect, evaluated by the bleeding rate after cutting the vessels. F1-10 method could sustain electrical current longer and effectively coagulate the tissue wider and deeper than the S method in the porcine model.

CONCLUSION

F1-10 method is suggested to achieve a stronger hemostatic effect than the S method in clinical procedures and ex vivo models.

Semen quality in a Giant Panda (Ailuropoda melanoleuca) in relation to estrus of a nearby resident female panda

Semen quality was determined in a sexually mature male Giant Panda, electroejaculated 13 times during a 5-year interval, before, during and after estrus of a female Giant Panda housed nearby. Testis volume and plasma testosterone concentrations were also measured. Mean testis volumes were 1223.0 +/- 64.7(S.E.M.)cm3 (before estrus), 1213.2 +/- 218.2 cm3 (during estrus), and 1360.2+/-160.4 cm3 (after estrus). Compared to before and during estrus in the female, testis volume decreased 70 days after estrus and there was no projectile ejaculation. The mean semen volume and sperm count were 2.2+/-0.7 mL and 8.3 +/- 3.1 x 10(8) before estrus, 2.4 +/- 0.9 mL and 5.7 +/- 0.9 x 10(8) during estrus, and 1.3 +/- 0.3 mL and 8.1 +/- 1.7 x 10(8) after estrus, respectively. The semen volume, sperm count, and testis volume markedly differed from 90 days before estrus until 66 days after estrus, whereas no marked differences in sperm motility, sperm viability, and proportion of morphologically abnormal spermatozoa were observed. Plasma testosterone concentrations were elevated both before and during estrus (0.62 +/- 0.23 ng/mL and 0.95 ng/mL), but decreased substantially after estrus (0.20 +/- 0.0 ng/mL). We inferred that spermatogenesis was active in this male panda from approximately 3 months before estrus to 2 months after estrus in the adjacent female.