Optical Emission Spectroscopy for the Real-Time Identification of Malignant Breast Tissue.

Breast conserving resection with free margins is the gold standard treatment for early breast cancer recommended by guidelines worldwide. Therefore, reliable discrimination between normal and malignant tissue at the resection margins is essential. In this study, normal and abnormal tissue samples from breast cancer patients were characterized ex vivo by optical emission spectroscopy (OES) based on ionized atoms and molecules generated during electrosurgical treatment. The aim of the study was to determine spectroscopic features which are typical for healthy and neoplastic breast tissue allowing for future real-time tissue differentiation and margin assessment during breast cancer surgery. A total of 972 spectra generated by electrosurgical sparking on normal and abnormal tissue were used for support vector classifier (SVC) training. Specific spectroscopic features were selected for the classification of tissues in the included breast cancer patients. The average classification accuracy for all patients was 96.9%. Normal and abnormal breast tissue could be differentiated with a mean sensitivity of 94.8%, a specificity of 99.0%, a positive predictive value (PPV) of 99.1% and a negative predictive value (NPV) of 96.1%. For 66.6% patients all classifications reached 100%. Based on this convincing data, a future clinical application of OES-based tissue differentiation in breast cancer surgery seems to be feasible.

Safety and effectiveness of a novel generator algorithm for bipolar vessel sealing: a randomised controlled chronic animal study.

BACKGROUND: Electrosurgical vessel sealers are gradually replacing conventional techniques such as ligation and clipping. Algorithms that control electrosurgical units (ESU), known as modes, are important for applications in different surgical disciplines. This chronic porcine animal study aimed to evaluate the safety and effectiveness of the novel thermoSEAL electrosurgical vessel sealing mode (TSM). The BiClamp® mode (BCM) of the renowned VIO® 300 D ESU served as control. BCM has been widely available since 2002 and has since been successfully used in many surgical disciplines. The TSM, for the novel VIO® 3 ESU, was developed to reduce sealing time and/or thermal lateral spread adjacent to the seal while maintaining clinical success rates. The primary aim of this study was to investigate the long-term and intraoperative seal quality of TSM. METHODS: The BiCision® device was used for vessel sealing with TSM and BCM in ten German Landrace pigs which underwent splenectomy and unilateral nephrectomy during the first intervention of the study. The seals were cut with the BiCision® knife. Ninety-nine arteries, veins and vascular bundles were chronically sealed for 5 or 21 days. Thereafter, during the second and terminal intervention of the study, 97 additional arteries and veins were sealed. The carotid arteries were used for histological evaluation of thermal spread. RESULTS: After each survival period, no long-term complications occurred with either mode. The intraoperative seal failure rates, i.e. vessel leaking or residual blood flow after the first sealing activation, were 2% with TSM versus 6% with BCM (p = 0.28). The sealing time was significantly shorter with TSM (3.5 ± 0.69 s vs. 7.3 ± 1.3 s, p < 0.0001). The thermal spread and burst pressure of arteries sealed with both modes were similar (p = 0.18 and p = 0.61) and corresponded to the histological evaluation. The measured tissue sticking parameter was rare with both modes (p = 0.33). Tissue charring did not occur. Regarding the cut quality, 97% of the seals were severed in the first and 3% in the second attempt (both with TSM and BCM). CONCLUSIONS: The novel TSM seals blood vessels twice as fast as the BCM while maintaining excellent tissue effect and clinical success rates. TRIAL REGISTRATION: Not applicable.

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.

A New Tool for Transbronchial Cryobiopsies in the Lung: An Experimental Feasibility ex vivo Study.

BACKGROUND: Transbronchial cryobiopsy (TBCB) is a minimally invasive procedure to establish a diagnosis of interstitial lung disease though with the disadvantage that samples have to be extracted together with the bronchoscope. OBJECTIVES: The aim of the present study was to evaluate the feasibility of a new cryoprobe with which biopsy samples can be obtained through the working channel of the flexible bronchoscope. METHODS: The feasibility of obtaining transbronchial specimens with TBCB was tested and the technique was compared to transbronchial forceps biopsy (TBFB) in a prospectively randomized ex vivo animal study using a standard flexible bronchoscopy technique. The rate of successful biopsies and the duration of the sampling procedure were recorded for both methods. Size and quality of the biopsies were histologically evaluated and measured. RESULTS: Biopsy samples could be obtained in 93.3% of TBCB and in 79.0% of TBFB procedures (p = 0.182). Sampling procedure time did not differ in any clinically relevant manner between the two methods. The mean specimen area of TBCB samples was significantly higher compared to that of TBFB samples (8.08 ± 5.80 vs. 2.61 ± 2.14 mm2; p < 0.0001). TBCB specimens showed less artifacts and a significantly higher percentage of alveolar tissue (53.57 vs. 25.42%; p = 0.0285) than TBFB specimens. CONCLUSIONS: It is feasible to retrieve TBCB samples of good quality and size with the new mini cryoprobe through the working channel of the bronchoscope, while the bronchoscope remains within the central airways throughout the whole procedure. Further studies are necessary to evaluate the safety and efficacy in an in vivo setting.