Cavitron ultrasonic surgical aspirator (CUSA) compared with conventional pancreatic transection in distal pancreatectomy: study protocol for the randomised controlled CUSA-1 pilot trial.

BACKGROUND: Postoperative pancreatic fistula (POPF) remains the most common and serious complication after distal pancreatectomy. Many attempts at lowering fistula rates have led to unrewarding insignificant results as still up to 30% of the patients suffer from clinically relevant POPF. Therefore, the development of new innovative methods and procedures is still a cornerstone of current surgical research.The cavitron ultrasonic surgical aspirator (CUSA) device is a well-known ultrasound-based parenchyma transection method, often used in liver and neurosurgery which has not yet been thoroughly investigated in pancreatic surgery, but the first results seem very promising. METHODS: The CUSA-1 trial is a randomised controlled pilot trial with two parallel study groups. This single-centre trial is assessor and patient blinded. A total of 60 patients with an indication for open distal pancreatectomy will be intraoperatively randomised after informed consent. The patients will be randomly assigned to either the control group with conventional pancreas transection (scalpel or stapler) or the experimental group, with transection using the CUSA device. The primary safety endpoint of this trial will be postoperative complications ≥grade 3 according to the Clavien-Dindo classification. The primary endpoint to investigate the effect will be the rate of POPF within 30 days postoperatively according to the ISGPS definition. Further perioperative outcomes, including postpancreatectomy haemorrhage, length of hospital stay and mortality will be analysed as secondary endpoints. DISCUSSION: Based on the available literature, CUSA may have a beneficial effect on POPF occurrence after distal pancreatectomy. The rationale of the CUSA-1 pilot trial is to investigate the safety and feasibility of the CUSA device in elective open distal pancreatectomy compared with conventional dissection methods and gather the first data on the effect on POPF occurrence. This data will lay the groundwork for a future confirmatory multicentre randomised controlled trial. ETHICS AND DISSEMINATION: The CUSA-1 trial protocol was approved by the ethics committee of the University of Heidelberg (No. S-098/2022). Results will be published in an international peer-reviewed journal and summaries will be provided in lay language to study participants and their relatives. TRIAL REGISTRATION NUMBER: DRKS00027474.

Top 10 research priorities in colorectal cancer: results from the Colorectal Cancer Priority-Setting Partnership.

BACKGROUND: Colorectal cancer (CRC) is the third most frequent cause of cancer death in the word. Which aspects of research into CRC should be accorded the highest priority remains unclear, because relevant stakeholders, such as patients, nurses, and physicians, played hardly any part in the development of research projects. The goal in forming the CRC Priority-Setting Partnership (PSP) was to bring all relevant stakeholders together to identify and prioritize unresolved research questions regarding the diagnosis, treatment, and follow-up of CRC. METHODS: The CRC PSP worked in cooperation with the British James Lind Alliance. An initial nationwide survey was conducted, and evidence uncertainties were collected, categorized, summarized, and compared with available evidence from the literature. The as-yet unresolved questions were (provisionally) ranked in a second national wide survey, and at a concluding consensus workshop all stakeholders came together to finalize the rankings in a nominal group process and compile a top 10 list. RESULTS: In the first survey (34% patients, 51% healthcare professionals, 15% unknown), 1102 submissions were made. After exclusion of duplicates and previously resolved questions, 66 topics were then ranked in the second survey (56% patients, 39% healthcare professionals, 5% unknown). This interim ranking process revealed distinct differences between relatives and healthcare professionals. The final top 10 list compiled at the consensus workshop covers a wide area of research topics. CONCLUSION: All relevant stakeholders in the CRC PSP worked together to identify and prioritize the top 10 evidence uncertainties. The results give researchers and funding bodies the opportunity to address the most patient-relevant research projects. It is the first detailed description of a PSP in Germany, and the first PSP on CRC care worldwide.

Central pancreatectomy prevents postoperative diabetes.

BACKGROUND: Central pancreatectomy (CP) can be performed as an alternative surgical approach to distal pancreatectomy (DP) in the treatment of benign or low-grade malignant lesions located in the neck and body of the pancreas, aiming to reduce loss of parenchyma and therefore organ failure. The objective of this study was to evaluate the short- and long-term outcome of CP in comparison to DP. METHODS: Patients who received CP in a large tertiary care pancreatic surgery center between 2001 and 2020 were identified from a prospectively maintained database and compared via propensity score matching with patients receiving DP during the same time period. Perioperative rate of complications and long-term outcome of pancreatic endocrine and exocrine function were evaluated. RESULTS: One hundred and seven patients undergoing open CP were compared to 107 patients with open DP. No significant difference in rates or severity of most surgical complications could be found including postoperative pancreatic fistula, intraabdominal fluid collection, delayed gastric emptying and wound infection. However, patients receiving CP had a significantly higher risk of grade C postpancreatectomy hemorrhage (PPH) (CP: 10 patients, 9.3% versus DP: 1 patient, 0.9%; p = .0019). Perioperative mortality was comparable. Long-term follow-up of 60 matched pairs revealed significantly less patients with new-onset diabetes after CP (eight patients, 13.3%) compared to DP (22 patients, 36.7%, p = .0056). CONCLUSION: CP offers an improved endocrine long-term outcome at the expense of a higher risk of PPH without increased perioperative mortality. As evidence on this parenchyma sparing surgical technique is sparse, more prospective data are needed.

Neural networks for estimation of facial palsy after vestibular schwannoma surgery.

PURPOSE: Facial nerve damage in vestibular schwannoma surgery is associated with A-train patterns in free-running EMG, correlating with the degree of postoperative facial palsy. However, anatomy, preoperative functional status, tumor size and occurrence of A-trains clusters, i.e., sudden A-trains in most channels may further contribute. In the presented study, we examine neural networks to estimate postoperative facial function based on such features. METHODS: Data from 200 consecutive patients were used to train neural feed-forward networks (NN). Estimated and clinical postoperative House and Brackmann (HB) grades were compared. Different input sets were evaluated. RESULTS: Networks based on traintime, preoperative HB grade and tumor size achieved good estimation of postoperative HB grades (chi2 = 54.8), compared to using tumor size or mean traintime alone (chi2 = 30.6 and 31.9). Separate intermediate nerve or detection of A-train clusters did not improve performance. Removal of A-train cluster traintime improved results (chi2 = 54.8 vs. 51.3) in patients without separate intermediate nerve. CONCLUSION: NN based on preoperative HB, traintime and tumor size provide good estimations of postoperative HB. The method is amenable to real-time implementation and supports integration of information from different sources. NN could enable multimodal facial nerve monitoring and improve postoperative outcomes.

Learning from EMG: semi-automated grading of facial nerve function.

The current grading of facial nerve function is based on subjective impression with the established assessment scale of House and Brackmann (HB). Especially for research a more objective method is needed to lower the interobserver variability to a minimum. We developed a semi-automated grading system based on (facial) surface EMG-data measuring the facial nerve function of 28 patients with vestibular schwannoma surgery. The sEMG was recorded preoperatively, postoperatively and after 3-12 months. In addition, the HB grade was determined. After manual selection and preprocessing, the data were subjected to machine learning classificators (Logistic regression, SVM and KNN). Lateralization indices were calculated and multivariant machine learning analysis was performed according to three scenarios [differentiation of normal (1) and slight (2) vs. impaired facial nerve function and classification of HB 1-3 (3)]. The calculated AUC for each scenario showed overall good differentiation capability with a median AUC of 0.72 for scenario 1, 0.91 for scenario 2 and multiclass AUC of 0.74 for scenario 3. This study approach using sEMG and machine learning shows feasibility regarding facial nerve grading in perioperative VS-surgery setting. sEMG may be a viable alternative to House Brackmann regarding objective evaluation of facial function especially for research purposes.

Safety and efficacy of TRIANGLE operation applied in pancreatic surgery: a protocol of the systematic review and meta-analysis.

BACKGROUND: Pancreatic surgery is regarded as the only curative treatment for pancreatic cancer (PC). As the neoadjuvant therapy is applied widely nowadays, the proportion of patients with PC undergoing surgery also with locally advanced tumour findings has increased accordingly. Especially in these situations, a radical resection of all tumour tissues is challenging. A novel surgical strategy has been introduced recently to achieve this aim, namely the TRIANGLE operation which comprises the radical resection of all nerve and lymphatic tissue between coeliac artery, superior mesenteric artery and mesenteric-portal axis without including extended lymphadenectomy outside this area. Due to currently published studies, Triangle Operation is a safe and feasible procedure. However, this has not been systematically analysed to date. This systematic review and meta-analysis aim to evaluate surgical and postoperative outcomes of Triangle Operation in pancreatic surgery. METHODS AND ANALYSIS: Pubmed, Web of Science and Cochrane Central Register of Controlled Trials in the Cochrane Library will be searched from inception until 31 December 2022. This study will include all articles comparing Triangle Operation versus non-Triangle Operation in pancreatic surgery to assess outcomes. The primary endpoints will be R0 resection rate and 1-year overall survival. The secondary endpoints will be delayed gastric emptying, postoperative pancreatic fistula, post pancreatectomy haemorrhages and reoperation incidence, overall complications, mortality and 3-year overall survival. The study selection, study quality assessment, data extraction and critical appraisal will be carried out by two reviewers. Inter-reviewer disagreements will be evaluated by discussion with a third reviewer. Besides, a subgroup analysis will be conducted focused on robotic surgery, laparoscopic surgery and open surgery in detail. Additionally, the Grading of Recommendations, Assessment, Development and Evaluations framework will be performed to evaluate the strength of evidence. ETHICS AND DISSEMINATION: This systematic review and meta-analysis will not require ethical approval. Results will be published in a peer-reviewed scientific journal. PROSPERO REGISTRATION NUMBER: CRD42021234721.

Intraoperative visualisation of pancreatic leakage (ViP): study protocol for an IDEAL Stage I Post Market Clinical Study.

INTRODUCTION: Pancreatic resections are an important field of surgery worldwide to treat a variety of benign and malignant diseases. Postoperative pancreatic fistula (POPF) remains a frequent and critical complication after partial pancreatectomy and affects up to 50% of patients. POPF increases mortality, prolongs the postoperative hospital stay and is associated with a significant economic burden. Despite various scientific approaches and clinical strategies, it has not yet been possible to develop an effective preventive tool. The SmartPAN indicator is the first surgery-ready medical device for direct visualisation of pancreatic leakage already during the operation. Applied to the surface of pancreatic tissue, it detects sites of biochemical leak via colour reaction, thereby guiding effective closure and potentially mitigating POPF development. METHODS AND ANALYSIS: The ViP trial is a prospective single-arm, single-centre first in human study to collect data on usability and confirm safety of SmartPAN. A total of 35 patients with planned partial pancreatectomy will be included in the trial with a follow-up of 30 days after the index surgery. Usability endpoints such as adherence to protocol and evaluation by the operating surgeon as well as safety parameters including major intraoperative and postoperative complications, especially POPF development, will be analysed. ETHICS AND DISSEMINATION: Following the IDEAL-D (Idea, Development, Exploration, Assessment, and Long term study of Device development and surgical innovation) framework of medical device development preclinical in vitro, porcine in vivo, and human ex vivo studies have proven feasibility, efficacy and safety of SmartPAN. After market approval, the ViP trial is the IDEAL Stage I trial to investigate SmartPAN in a clinical setting. The study has been approved by the local ethics committee as the device is used exclusively within its intended purpose. Results will be published in a peer-reviewed journal. The study will provide a basis for a future randomised controlled interventional trial to confirm clinical efficacy of SmartPAN. TRIAL REGISTRATION NUMBER: German Clinical Trial Register DRKS00027559, registered on 4 March 2022.