Ex-vivo investigation on the potential of 1470 nm diode laser light for enucleation of uterine leiomyoma

Abstract Background and objective: Patients suffering from uterine leiomyoma are often treated by hysterectomy or organ preserving myoma enucleation using electrosurgical, ultrasonic or radio-frequency techniques. Considerable thermal tissue damage leads to the development of scar formation which in the long term may result in complications during pregnancy. Therefore alternative techniques are required. Materials and methods: After ethical approval, human uteri myomatosus were used to investigate the interaction of 1470 nm diode laser light (Medilas D MultiBeam; Dornier MedTech Laser GmbH, Weßling, Germany) during surgical procedures (laser mode, continuous wave; laser power, 5–30 W; fiber core diameter, 600 μm; cutting velocity, 3 mm/s). Macroscopic and microscopic evaluation was performed to improve understanding of tissue ablation and coagulation processes. Additionally laser-assisted ex-vivo myoma enucleation procedures were performed to assess handling and applicability. Descriptive and correlation statistics were used for evaluation. Results: The macroscopic visible coagulation rim was calculated to be at a maximum of ~550 μm in lateral direction (superficial width), and ~300 μm in axial plane (sagittal depth). Microscopic examination of hematoxylin and eosin stained sagittal tissue slices showed a largest ablation depth of 279.1±186.8 μm and a maximum irreversibly damaged remaining tissue depth of 628.7±354.3 μm when a laser power of 30 W was applied. The ratio of the remaining tissue and ablation depth indicates that increased applied laser power results in a faster ablation than coagulation into the depth. Hands-on ex-vivo myoma enucleation at power levels of 20–25 W showed an ideal preparation situation with the potential for sufficient surface coagulation when the fiber-tissue distance is adjusted to 5–10 mm. Conclusion: Sufficient and effective ablation and coagulation of uterus myomatosus tissue and the ex-vivo myoma enucleation showed the potential of the 1470 nm diode laser as an innovative surgical tool for myoma enucleation. Based upon this study it should be clinically validated whether this procedure could become an alternative application in endoscopic surgery in gynecology.