Plasma Device Functions and Tissue Effects in the Female Pelvis-A Systematic Review

Medical use of (non-)thermal plasmas is an emerging field in gynaecology. However, data on plasma energy dispersion remain limited. This systematic review presents an overview of plasma devices, fields of effective application, and impact of use factors and device settings on tissues in the female pelvis, including the uterus, ovaries, cervix, vagina, vulva, colon, omentum, mesenterium, and peritoneum. A search of the literature was performed on 4 January 2023 in the Medline Ovid, Embase, Cochrane, Web of Science, and Google Scholar databases. Devices were classified as plasma-assisted electrosurgery (ES) using electrothermal energy, neutral argon plasma (NAP) using kinetic particle energy, or cold atmospheric plasma (CAP) using non-thermal biochemical reactions. In total, 8958 articles were identified, of which 310 were scanned, and 14 were included due to containing quantitative data on depths or volumes of tissues reached. Plasma-assisted ES devices produce a thermal effects depth of <2.4 mm. In turn, NAP effects remained superficial, <1.0 mm. So far, the depth and uniformity of CAP effects are insufficiently understood. These data are crucial to achieve complete treatment, reduce recurrence, and limit damage to healthy tissues (e.g., prevent perforations or preserve parenchyma). Upcoming and potentially high-gain applications are discussed, and deficits in current evidence are identified.

Prevention of Peritoneal Adhesions by Non-Thermal Dielectric Barrier Discharge Plasma Treatment on Mouse Model: A Proof of Concept Study

Purposes: Formation of peritoneal adhesions is a common consequence of abdominopelvic surgeries and remarkably increases the mortality and morbidity. Moreover, peritoneal adhesions linked to chronic abdominopelvic pain and infertility in women. Various attempts for prevention of peritoneal adhesions were reported. However, these methods either remain insufficient to prevent formation of peritoneal adhesions or carry some practical limitations and thus, there is a need for novel techniques that could effectively decrease the formation of peritoneal adhesions. The aim of the present prospective, randomized, controlled, and single blinded study was to evaluate the effect of non-thermal atmospheric plasma (NTAP) treatment on prevention of peritoneal adhesions. Materials and Methods: Sixteen male CD-1 mice were randomly divided into two groups: control and plasma. Excisional and abrasion adhesion models were generated on the peritoneal side wall and cecum, respectively. Ten days after creating adhesion models, mice were sacrificed and adhesion formations were evaluated macroscopically using Knightly's and Linsky's grading systems to assess the intensity and extent of adhesions, respectively. Zühlke's grading system was used for microscopic assessment of adhesions. Results: The mean scores for peritoneum and cecum in control group according to Knightly's grading system were determined as 3.3 and 2.6, respectively. In NTAP-treated group, Knightly's score was determined as 1.6 and 0.5 for peritoneum and cecum, respectively. NTAP treatment reduced Linsky's score from 3.8 to 1.3 and 2.1 to 1.1 on peritoneum and cecum. Finally, in microscopic evaluation, NTAP treatment reduced Zühlke's score from 3.4 to 1.5 and 2.6 to 1.3 for peritoneum and cecum, respectively. Conclusions: The results of the present proof of concept study suggest that NTAP could be a novel method to reduce and/or prevent the formation of peritoneal adhesions after abdominopelvic surgeries.

A prospective randomized experimental study to investigate the peritoneal adhesion formation after waterjet injection and argon plasma coagulation (HybridAPC) in a rat model

BACKGROUND

This prospective, randomized, controlled, single-blinded study investigates the peritoneal adhesion formation of HybridAPC (waterjet elevation of the peritoneum with subsequent argon plasma coagulation) versus only waterjet (elevation with the same instrument, but without subsequent argon plasma coagulation) in a rat model (24 female Wistar rats).

MATERIALS AND METHODS

Bilateral lesions were created on the abdominal wall with HybridAPC on one sidewall and waterjet elevation on the other sidewall of the peritoneum in a standard fashion. After 10 days, the rats were euthanized to evaluate the peritoneal trauma sites.

MAIN OUTCOME MEASURE(S)

Adhesion incidence, quantity, and quality were scored 10 days postoperatively and studied histopathologically.

RESULT(S)

Incidence of adhesion formation was 2.3% for HybridAPC; no adhesions occurred for peritoneal elevation with saline (p = 1.00). Histologic evaluation revealed no acute inflammation in both groups. An overall moderate degree of granulation tissue formation and myonecrosis was observed in the HybridAPC group, whereas no chronic inflammation and myonecrosis occurred after elevation without thermal ablation (p < 0.0001).

CONCLUSION(S)

This study investigates the effect of waterjet elevation of the peritoneum with and without subsequent thermal ablation on adhesion formation in a rat model for the first time. Peritoneal waterjet elevation with saline does not provide any risk of adhesion formation. Thermal coagulation with APC after waterjet elevation of the peritoneum creates advantageous peritoneal conditions due to a permanent moist tissue surface and the cooling effect of the injected solution, resulting in no significant difference in adhesion formation compared to peritoneal elevation without thermal ablation. HybridAPC can thus be regarded as a beneficial coagulation method with only minor adhesion formation due to positive tissue effects of the combined waterjet.

A Prospective Randomized Experimental Study to Investigate the Eradication Rate of Endometriosis after Surgical Resection versus Aerosol Plasma Coagulation in a Rat Model

PURPOSE

To investigate the eradication rate of endometriosis after surgical resection (SR) vs. thermal ablation with aerosol plasma coagulation (AePC) in a rat model.

METHODS

In this prospective, randomized, controlled, single-blinded animal study endometriosis was induced on the abdominal wall of 34 female Wistar rats. After 14 days endometriosis was either removed by SR or ablated by AePC. 14 days later the rats were euthanized to evaluate the eradication rate histopathologically. Intervention times were recorded.

RESULTS

Eradication rate of endometriosis after 14 days did not significantly differ between AePC and SR (p=0.22). Intervention time per endometrial lesion was 22.1 s for AePC and 51.8 s for SR (p<0.0001).

CONCLUSIONS

This study compares the eradication rate of the new aerosol plasma coagulation device versus standard surgical resection of endometriosis in a rat model. Despite being a thermal method, AePC showed equality towards SR regarding eradication rate but with significantly shorter intervention time.