Transection Site Research Articles

Double arch technique - a novel surgical procedure for the hypoplastic aortic arch syndrome

Abstract Background The hypoplastic aortic arch syndrome was defined as a combination of hypoplastic aortic arch and complex proximal descending aortic anomalies (such as aortic aneurysm, aortic coarctation, aortic tortuosity, or aortic dissection). In this study, we proposed a novel 'double arch' technique as a simple surgical procedure to treat the hypoplastic aortic arch syndrome, which could eliminate the requirement for cardiopulmonary bypass. Purpose This study aimed to investigate the surgical outcomes of patients who underwent the 'double arch' technique, and further evaluate the effectiveness and safety of this novel technique. Methods Briefly, J-shaped mini-sternotomy and left posterolateral thoracotomy were both performed in this technique. The ascending aorta, aortic arch, and proximal descending aorta were dissociated. After that, the ascending aorta was occluded using a side-biting clamp, followed by an end-to-side anastomosis between the proximal end of vascular graft and the ascending aorta. Similarly, the thoracic descending aorta was occluded with two aortic clamps beyond the opening of the left subclavian artery, and was then transected between the clamps, followed by an end-to-end anastomosis between the distal end of vascular graft and the distal descending aorta, while the proximal descending aorta was closed with sutures. The transection site of the aorta could be adjusted according to the extent of the lesions, and the vascular graft was placed in the left thoracic cavity. The operation was performed at room temperature. The primary endpoint was early mortality, which referred to in-hospital death and/or death within 30 days after surgery (including intraoperative death), whichever is longer. Critical secondary endpoints included aortic reoperation, newly developed aneurysms, and the blood pressure difference between the upper and lower extremities. Results Twelve patients with hypoplastic aortic arch syndrome were enrolled from December 2015 to February 2022. Patients were diagnosed using computed tomography. The median age (interquartile range, IQR) was 26.5 (17.0, 39.0) years (ranging from 12.0 to 55.0), and 8 patients were female (66.7%). The median operation time (IQR) was 4.7 (3.8, 5.5) hours (ranging from 2.8 to 7.3). All patients survived to discharge and completed the follow-up. The median follow-up time (IQR) was 5.42 (3.25, 5.97) years (ranging from 0.02 to 6.25). During the follow-up, no patient died or was required for reoperation. In addition, no newly developed aneurysm was found, and no severe adverse event was recorded. The median blood pressure difference (IQR) between the upper and lower extremities was 9 (4, 17) mmHg (ranging from 3 to 27). Conclusions The 'double arch' technique is a viable alternative surgical treatment for the hypoplastic aortic arch syndrome. This technique is expected to significantly simplify the surgical procedure and improve the long-term prognosis of patients.Diagram of the 'double arch' techniqueCT scans of pre- and post-operation

Real-time segmentation of biliary structure in pure laparoscopic donor hepatectomy

Pure laparoscopic donor hepatectomy (PLDH) has become a standard practice for living donor liver transplantation in expert centers. Accurate understanding of biliary structures is crucial during PLDH to minimize the risk of complications. This study aims to develop a deep learning-based segmentation model for real-time identification of biliary structures, assisting surgeons in determining the optimal transection site during PLDH. A single-institution retrospective feasibility analysis was conducted on 30 intraoperative videos of PLDH. All videos were selected for their use of the indocyanine green near-infrared fluorescence technique to identify biliary structure. From the analysis, 10 representative frames were extracted from each video specifically during the bile duct division phase, resulting in 300 frames. These frames underwent pixel-wise annotation to identify biliary structures and the transection site. A segmentation task was then performed using a DeepLabV3+ algorithm, equipped with a ResNet50 encoder, focusing on the bile duct (BD) and anterior wall (AW) for transection. The model’s performance was evaluated using the dice similarity coefficient (DSC). The model predicted biliary structures with a mean DSC of 0.728 ± 0.01 for BD and 0.429 ± 0.06 for AW. Inference was performed at a speed of 15.3 frames per second, demonstrating the feasibility of real-time recognition of anatomical structures during surgery. The deep learning-based semantic segmentation model exhibited promising performance in identifying biliary structures during PLDH. Future studies should focus on validating the clinical utility and generalizability of the model and comparing its efficacy with current gold standard practices to better evaluate its potential clinical applications.

Recovery of independent ambulation after complete spinal cord transection in the presence of the neuroprotectant polyethylene glycol in monkeys

ObjectiveDespite the conventional belief that motor function and sensation distal to the site of a complete spinal cord transection are irretrievable, our research has demonstrated significant motor recovery in mice, rats, and dogs by applying polyethylene glycol (PEG) topically via a syringe directly to the contact interface of transected spinal cord. However, before implementing this technology in human subjects, validating PEG's efficacy and enduring impact through experimentation on non-human primates is imperative. MethodsTwo 4-year-old female Macaca fascicularis monkeys underwent complete dorsal cord transection at T10. Postoperative behavioral assessment, electrophysiologic monitoring, and neuroimaging examinations were recorded, and tissues were obtained for histological examination at the end of study. ResultsThe monkey whose spinal cord had been fully transected in the presence of PEG developed useful recovery already at 3 months and near-complete recovery of motor function in the hind-limbs at 18 months. The control animal without PEG remained paralyzed. Cortical somatosensory evoked potentials recovered postoperatively only in PEG-treated monkey vs none in the control. Diffusion tensor imaging showed re-establishment of continuity of the white matter in PEG-treated monkey, but not in the control. Moreover, histology revealed intact neuronal bodies, axons, and myelin tissue at the spinal cord transection site in PEG-treated monkey only. ConclusionThis report suggests that in primates, an acutely transected spinal cord can be re-fused in the presence of PEG with restoration of neural continuity and functional recovery of motor activity distal to the site of transection.

Transperineal anastomotic urethroplasty with distal transection versus proximal transection: How to predict?

Abstract Objectives To evaluate the pubourethral stump angle (PUA) to determine the site of urethral transection during transperineal anastomotic urethroplasty (TAU). Patients and methods Patients diagnosed with pelvic fracture urethral distraction defect who underwent preoperative magnetic resonance (MR) urethrography and were treated with TAU between June 2019 and December 2021 were retrospectively reviewed. According to the site of urethral transection during TAU, patients were classified into proximal and distal groups receiving TAU with proximal and distal transection, respectively. The demographic and clinical data were recorded. The PUA was measured on sagittal T2-weighted MR urethrography. The relationship between the site of urethral transection and PUA was analyzed. Results Sixty-seven patients were included. Forty-one and 26 patients were included in the proximal and distal groups, respectively. Finally, the success rates in the proximal and distal groups were 95.1% and 92.3%, respectively. The PUAs were 123.7° ± 14.6° and 86.5° ± 9.8° (p = 0.005), respectively. The curves for the 2 groups intersected between 90° and 110°. The scribing effects at 90°, 100°, and 110° in the 2 groups were compared in detail. Compared with 90° and 110°, 100° had the highest sensitivity as the demarcation line. Conclusions In the treatment of pelvic fracture urethral distraction defect, the PUA on MR urethrography is an objective and valid parameter for evaluating the site of urethral transection during TAU. A PUA >100° indicates that proximal transection should be preferentially attempted.

Impact of pancreas transection site on incidence of pancreatic fistula after distal pancreatectomy: a propensity score matched study

BackgroundDistal pancreatectomy (DP) is performed for lesions in the body and tail of the pancreas. The morbidity profile is considerable, mainly due to clinically relevant postoperative pancreatic fistula (CR-POPF). This study aims to investigate potential differences in CR-POPF related to transection site. MethodsAn observational cohort study from a prospectively maintained database was performed. Subtotal distal pancreatectomy (SDP) was defined as transection over the superior mesenteric vein, and DP was defined as transection lateral to this point. Propensity score matching (PSM) in 1:1 fashion was applied based on demographical and perioperative variables. ResultsSix hundred and six patients were included in the analysis (1997–2020). Four hundred twenty (69.3%) underwent DP, while 186 (30.7%) underwent SDP. The rate of CR-POPF was 19.3% after DP and 20.4% after SDP (p = 0.74). SDP was associated with older age (63.1 vs 60.1 years, p = 0.016), higher occurrence of ductal adenocarcinoma (37.1 vs 17.6%, p = 0.001) and more frequent use of neoadjuvant chemotherapy (3.8 vs 0.7%, p = 0.012). After PSM, 155 patients were left in each group. The difference in CR-POPF between DP and SDP remained statistically non-significant (20.6 vs 18.7%, p = 0.67). ConclusionThis study found no difference in CR-POPF related to transection site during distal pancreatectomy.

Developing preclinical dog models for reconstructive severed spinal cord continuity via spinal cord fusion technique

BackgroundSpinal cord injury (SCI) is a severe impairment of the central nervous system, leading to motor, sensory, and autonomic dysfunction. The present study investigates the efficacy of the polyethylene glycol (PEG)-mediated spinal cord fusion (SCF) techniques, demonstrating efficacious in various animal models with complete spinal cord transection at the T10 level. This research focuses on a comparative analysis of three SCF treatment models in beagles: spinal cord transection (SCT), vascular pedicle hemisected spinal cord transplantation (vSCT), and vascularized allograft spinal cord transplantation (vASCT) surgical model. MethodsSeven female beagles were included in the SCT surgical model, while four female dogs were enrolled in the vSCT surgical model. Additionally, twelve female dogs underwent vASCT in a paired donor-recipient setup. Three surgical model were evaluated and compared through electrophysiology, imaging and behavioral recovery. ResultsThe results showed a progressive recovery in the SCT, vSCT and vASCT surgical models, with no statistically significant differences observed in cBBB scores at both 2-month and 6-month post-operation (both P>0.05). Neuroimaging analysis across the SCT, vSCT and vASCT surgical models revealed spinal cord graft survival and fiber regrowth across transection sites at 6 months postoperatively. Also, positive MEP waveforms were recorded in all three surgical models at 6-month post-surgery. ConclusionThe study underscores the clinical relevance of PEG-mediated SCF techniques in promoting nerve fusion, repair, and motor functional recovery in SCI. SCT, vSCT, and vASCT, tailored to specific clinical characteristics, demonstrated similar effective therapeutic outcomes.

Lineage tracing reveals a novel PDGFRβ+ satellite cell subset that contributes to myo-regeneration of chronically injured rotator cuff muscle

Massive rotator cuff (RC) tendon tears are associated with progressive fibro-adipogenesis and muscle atrophy that altogether cause shoulder muscle wasting. Platelet derived growth factor β (PDGFRβ) lineage cells, that co-express PDGFRα have previously been shown to directly contribute to scar formation and fat accumulation in a mouse model of irreversible tendon and nerve transection (TTDN). Conversely, PDGFRβ+ lineage cells have also been shown to be myogenic in cultures and in other models of skeletal muscle injury. We therefore hypothesized that PDGFRβ demarcates two distinct RC residing subpopulations, fibro-adipogenic and myogenic, and aimed to elucidate the identity of the PDGFRβ myogenic precursors and evaluate their contribution, if any, to RC myo-regeneration. Lineage tracing revealed increasing contribution of PDGFRβ+ myo-progenitors to the formation of GFP+ myofibers, which were the most abundant myofiber type in regenerated muscle at 2 weeks post-TTDN. Muscle regeneration preceded muscle atrophy and both advanced from the lateral site of tendon transection to the farthest medial region. GFP+/PDGFRβ+Sca-1−lin−CXCR4+Integrin-β1+ marked a novel subset of satellite cells with confirmed myogenic properties. Further studies are warranted to identify the existence of PDGFRβ+ satellite cells in human and other mouse muscles and to define their myo-regenerative potential following acute and chronic muscle injury.

Intraoperative Video Analysis of Pancreatic Stump and Stapler Closure-Induced Pancreatic Fistula in Laparoscopic Distal Pancreatectomy: A Retrospective Study.

Objectives Pancreatic stump closure in laparoscopic distal pancreatectomy (Lap-DP) is commonly performed using an automatic stapler. Herein, the magnification effect of laparoscopy was used to observe the pancreatic stump and retrospectively investigate factors that may cause postoperative pancreatic fistula. Methods This is a single-center retrospective study. We selected 62 cases of Lap-DP performed between March 2016 and May 2022. We retrospectively analyzed 54 cases where pancreatic transection sites could be observed using an intraoperative video. Pancreatic transection was performed using the Powered ECHELON FLEX®+ GST® System (Ethicon, Somerville, USA). For quantitative studies, we investigated the factors that cause pancreatic fistula and other factors causing pancreatic fistula. Results Pancreatic parenchymal hemorrhage and injury occurred in 22.2% and 29.6% of cases, respectively. International Study Group of Pancreatic Surgery grade B/C pancreatic fistula was observed in 12 cases (22.2%). Univariate analysis of pancreatic (n = 12) and nonpancreatic (n = 42) fistula groups showed no significant differences in pancreatic thickness. The pancreatic fistula group had a significantly high incidence of the hard pancreas (p = .009), pancreatic parenchymal bleeding (p = .002), and pancreatic parenchymal damage (p < .001). Multivariate analysis revealed that pancreatic parenchymal damage was an independent cause of pancreatic fistula (hazard ratio, 81.4 (8.5-772.3), p < .001). Conclusion Pancreatic parenchymal damage due to compression during pancreatic stump closure using an automatic stapler in Lap-DP may cause pancreatic fistula.

Clinical and computational development of a patient-calibrated ICGFA bowel transection recommender

IntroductionIntraoperative indocyanine green fluorescence angiography (ICGFA) aims to reduce colorectal anastomotic complications. However, signal interpretation is inconsistent and confounded by patient physiology and system behaviours. Here, we demonstrate a proof of concept of a novel clinical and computational method for patient calibrated quantitative ICGFA (QICGFA) bowel transection recommendation.MethodsPatients undergoing elective colorectal resection had colonic ICGFA both immediately after operative commencement prior to any dissection and again, as usual, just before anastomotic construction. Video recordings of both ICGFA acquisitions were blindly quantified post hoc across selected colonic regions of interest (ROIs) using tracking-quantification software and computationally compared with satisfactory perfusion assumed in second time-point ROIs, demonstrating 85% agreement with baseline ICGFA. ROI quantification outputs detailing projected perfusion sufficiency-insufficiency zones were compared to the actual surgeon-selected transection/anastomotic construction site for left/right-sided resections, respectively. Anastomotic outcomes were recorded, and tissue lactate was also measured in the devascularised colonic segment in a subgroup of patients. The novel perfusion zone projections were developed as full-screen recommendations via overlay heatmaps.ResultsNo patient suffered intra- or early postoperative anastomotic complications. Following computational development (n = 14) the software recommended zone (ROI) contained the expert surgical site of transection in almost all cases (Jaccard similarity index 0.91) of the nine patient validation series. Previously published ICGFA time-series milestone descriptors correlated moderately well, but lactate measurements did not. High resolution augmented reality heatmaps presenting recommendations from all pixels of the bowel ICGFA were generated for all cases.ConclusionsBy benchmarking to the patient’s own baseline perfusion, this novel QICGFA method could allow the deployment of algorithmic personalised NIR bowel transection point recommendation in a way fitting existing clinical workflow.

Biomechanical comparison of composite and cadaveric humeri models in experiments on operated humeral shaft fractures

A study was undertaken to determine how well contacting fracture fragments of composite bone replicated the behavior of fracture fragments in real bone. Ten composite and ten real humeral diaphyses were transected and reconstructed with limited-contact dynamic-compression plates. Two screws were placed on each side of the transection site and a calibrated electronic sensor sheet was placed between the imitated fracture fragments. After insertion of the distal screws, pressure measurements were made during insertion of the first proximal screw in compression mode, during insertion of the second screw in compression mode after loosening the first screw, and finally after retightening the first screw. The process was repeated after bending the plate. The contact area, the net compression force and the average compressive stress were computed and statistically compared. The composite bone and cadaveric bone differed in contact area and compressive stress but not in net compressive force. Plate bending did not produce a significant difference between composite and cadaveric bone. The results indicate that composite bone does not reproduce all the local fracture fragment conditions so that hardware testing in composite bone should proceed carefully. A gap between fracture fragments as is often used in comminuted fracture tests may remain as the most appropriate situation for fracture hardware testing.

Restoration of injured motoneurons reduces microglial proliferation in the adult rat facial nucleus.

In the axotomized facial nucleus (axotFN), the levels of choline acetyltransferase, vesicular acetylcholine transporter, and gamma amino butyric acid A receptor α1 are decreased, after which the microglia begin to proliferate around injured motoneuron cell bodies. We conjectured that an injury signal released from the injured motoneurons triggers the microglial proliferation in the axotFN. However, it is unclear whether the level of microglial proliferation is dependent on the degree of motoneuronal insult. In this study, we investigated the relationship between the extents of motoneuronal injury and microglial proliferation in a rat axotFN model. Administration of glial cell line-derived neurotrophic factor, N-acetyl L-cysteine, or salubrinal at the transection site ameliorated the increase in c-Jun and the reductions in levels of phosphorylated cAMP response element binding protein (p-CREB) and functional molecules in the injured motoneurons. Concurrently, the levels of the microglial marker ionized calcium-binding adapter molecule 1 and of macrophage colony-stimulating factor (cFms), proliferating cell nuclear antigen, and p-p38/p38 were significantly downregulated in microglia. These results demonstrate that the recovery of motoneuron function resulted in the reduction in microglial proliferation. We conclude that the degree of neuronal injury regulates the levels of microglial proliferation in the axotFN.

Impact of pancreas transection site on incidence of pancreatic fistula after distal pancreatectomy – a propensity score matched study

Impact of pancreas transection site on incidence of pancreatic fistula after distal pancreatectomy – a propensity score matched study

Impact of standardising indocyanine green fluorescence angiography technique for visual and quantitative interpretation on interuser variability in colorectal surgery.

Intra-operative colonic perfusion assessment via indocyanine green fluorescence angiography (ICGFA) aims to address malperfusion-related anastomotic complications; however, its interpretation suffers interuser variability (IUV), especially early in ICGFA experience. This work assesses the impact of a protocol developed for both operator-based judgement and computational development on interpretation consistency, focusing on senior surgeons yet to start using ICGFA. Experienced and junior gastrointestinal surgeons were invited to complete an ICGFA-experience questionnaire. They subsequently interpreted nine operative ICGFA videos regarding perfusion sufficiency of a surgically prepared distal colon during laparoscopic anterior resection by indicating their preferred site of proximal transection using an online annotation platform (mindstamp.com). Six ICGFA videos had been prepared with a clinical standardisation protocol controlling camera and patient positioning of which three each had monochrome near infrared (NIR) and overlay display. Three others were non-standardised controls with synchronous NIR and overlay picture-in-picture display. Differences in transection level between different cohorts were assessed for intraclass correlation coefficient (ICC) via ImageJ and IBM SPSS. 58 clinicians (12 ICGFA experts, 46 ICGFA inexperienced of whom 23 were either finished or within one year of finishing training and 23 were junior trainees) participated as per power calculations. 63% felt that ICGFA should be routinely deployed with 57% believing interpretative competence requires 11-50 cases. Transection level concordance was generally good (ICC = 0.869) across all videos and levels of expertise (0.833-0.915). However, poor agreement was evident with the standardised protocol videos for overlay presentation (0.208-0.345). Similarly, poor agreement was seen for the monochrome display (0.392-0.517), except for those who were trained but ICG inexperienced (0.877) although even here agreement was less than with unstandardised videos (0.943). Colorectal ICGFA acquisition and display standardisation impacts IUV with this specific protocol tending to diminish surgeon interpretation consistency. ICGFA video recording for computational development may require dedicated protocols.

Peri-firing compression in prevention of pancreatic fistula after distal pancreatectomy: A systematic review and a cohort study.

Clinically relevant postoperative pancreatic fistula (CR-POPF) after distal pancreatectomy (DP) occurs in 20%-40% of patients and remains a leading cause of morbidity and increased healthcare cost in this patient group. Recently, several studies suggested decreased risk of CR-POPF with the use of peri-firing compression (PFC) technique. The aim of this report was to conduct a systematic review to get an overview of the current knowledge on the use of PFC in DP. In addition, our experience with PFC was presented. The systematic literature review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Also, 19 patients undergoing DP with the use of PFC at Oslo University Hospital were studied. The primary endpoint was incidence of CR-POPF. Seven articles reporting a total of 771 patients were ultimately included in the systematic review. Only two of these were case-control studies examining outcomes in patients with and without PFC, while the rest were case series. These were heterogeneous in terms of staplers used, cartridge selection policy, and PFC technique. Both case-control studies reported significantly reduced CR- POPF incidence with PFC. Eight (21%) of our patients developed CR-POPF after DP with PFC. Only one patient developed CR-POPF among those with pancreatic transection site thickness ⩽1.5 cm. Evidence on potential benefits of PFC in DP is limited in quantity and quality. Our findings suggest that the use of PFC does not lead to reduction in the incidence of CR-POPF. Yet, there might be a benefit from PFC when dealing with a thin pancreas.

EGS P38 Audit of operative notes/ Clinical documentation of emergency laparotomy &amp; laparoscopic bowel resection procedures

Abstract Background Laparotomies and laparoscopic bowel resections are common emergency procedures carried out in General Surgery emergency theatres. Get It Right First Time (GIRFT), Royal College of Surgeons (RCS) and The Association of Surgeons of Great Britain and Ireland (ASGBI) have made best practice recommendations for documenting operative notes, to ensure effective communication with colleagues and for medicolegal purposes. Ensuing medicolegal issues and patient complaints have cost departments in recent times, due to poor documentation. This audit within a busy General surgery unit, assesses the quality of operative documentations against the standards set by GIRFT, RCS and ASGBI. Methods A retrospective audit of operative notes and relevant clinical documentation of 100 emergency laparotomies and laparoscopic bowel resections between August 2022 and March 2023 at a local General surgery unit. Patient Identification Numbers were extracted from the National Emergency Laparotomy Audit (NELA) database. Operative records and clinical documentations were obtained from electronic clinical records. The recommendations from the “GIRFT RCS and ASGBI Best Practice for Laparotomy and Laparoscopic Bowel Resection Surgery Documentation” guidance was used as the Standard. Up to 60 variables were assessed across different stages of the patient journey, from preoperative to intraoperative and postoperative stages. Results In the period reviewed, there was varying performance. Good performance in documentations of Indications, Operator names, patient position, incision, and findings, seen in 99, 100, 100, 100 and 100 percent of cases respectively. Anaesthetist name was documented in 48% of cases, whilst WHO checklist was documented in only 20% of cases. 64 of these cases had bowel resections. In this cohort, methods and location of resection was described in 95% of cases. Only 43% had the state of bowel prefusion at transection site documented. VTE prophylaxis, Antibiotics, sutures/clip plan, were documented in 87, 65 and 13 % of cases respectively. Conclusions The audit highlights deficits in important areas of documentation, despite the set guideline. Important medicolegal issues can arise when documentations are not clear, and steps considered routine as not written in the operative notes or patient’s records. The findings will be disseminated, and recommendations will be suggested across all grades of surgeons, with the aim to re-audit and improve quality of documentation and ultimately improve delivery of surgical care. A plan to have electronic documentation template or checklist for these procedures has been carried out for trial with the aim of developing standardised documentation process.

External validation of fistula risk scores for postoperative pancreatic fistula after distal pancreatectomy

BackgroundFistula risk scores such as distal fistula risk scores and DISPAIR have been recently developed to assess the risk of clinically relevant postoperative pancreatic fistula after distal pancreatectomy. This study aimed to validate these models externally using a large-scale Chinese cohort. MethodsThe study enrolled adult patients who underwent distal pancreatectomy at a high-volume single center between January 2011 and December 2021. The clinically relevant postoperative pancreatic fistula was defined as grade B/C, according to the 2016 International Study Group of Pancreatic Surgery. Model performance was evaluated using the area under the curve. ResultsAmong 653 eligible patients, 126 (19.3%) suffered from clinically relevant postoperative pancreatic fistulas. Independent predictors for clinically relevant postoperative pancreatic fistulas included body mass index, diabetes mellitus, pancreatic thickness at both neck and transection sites, main pancreatic duct diameter, and soft pancreas. Clinically relevant postoperative pancreatic fistula risk increased with increasing score severity. All 3 prediction models showed acceptable discrimination, with area under the curve values of preoperative distal fistula risk score at 0.723 (95% confidence interval 0.687–0.757), intraoperative distal fistula risk score at 0.737 (95% confidence interval 0.701–0.770), and DISPAIR at 0.721 (95% confidence interval 0.685–0.755). No significant differences were found among them. ConclusionDistal fistula risk scores and DISPAIR are useful tools for predicting clinically relevant postoperative pancreatic fistula after distal pancreatectomy, highlighting their importance in guiding surgical approach decisions and mitigating strategies against this complication in clinical practice.

Treatments with the specific δ-secretase inhibitor, compound 11, promote the regeneration of motor and sensory axons after peripheral nerve injury.

Limited axon regeneration following peripheral nerve injury may be related to activation of the lysosomal protease, asparaginyl endopeptidase (AEP, δ-secretase) and its degradation of the microtubule associated protein, Tau. Activity of AEP was increased at the site of sciatic nerve transection and repair but blocked in mice treated systemically with a specific AEP inhibitor, compound 11 (CP11). Treatments with CP11 enhanced axon regeneration in vivo. Amplitudes of compound muscle action potentials recorded 4 weeks after nerve transection and repair and 2 weeks after daily treatments with CP11 were double those of vehicle-treated mice. At that time after injury, axons of significantly more motor and sensory neurons had regenerated successfully and reinnervated the tibialis anterior and gastrocnemius muscles in CP11-treated mice than vehicle-treated controls. In cultured adult dorsal root ganglion neurons derived from wild type mice that were treated in vitro for 24 h with CP11, neurites were nearly 50% longer than in vehicle-treated controls and similar to neurite lengths in cultures treated with the TrkB agonist, 7,8-dihydroxyflavone (7,8-DHF). Combined treatment with CP11 and 7,8-DHF did not enhance outgrowth more than treatments with either one alone. Enhanced neurite outgrowth produced by CP11 was found also in the presence of the TrkB inhibitor, ANA-12, indicating that the enhancement was independent of TrkB signalling. Longer neurites were found after CP11 treatment in both TrkB+ and TrkB- neurons. Delta secretase inhibition by CP11 is a treatment for peripheral nerve injury with great potential.

Comparison of outcomes with stapler versus hand-sewn closure of the pancreatic stump following minimally invasive distal pancreatectomy: a retrospective cohort study

Background: Pancreatic fistula after distal pancreatectomy is a common and potentially lethal complication. The optimal closure method for the pancreatic remnant during minimally invasive distal pancreatectomy (MDP) remains unclear. Methods: Data of consecutive patients who underwent MDP in our institution between July 2018 and June 2021 were collected. The outcomes of MDP with stapler and hand-sewn closure were compared. The primary outcome was clinically relevant postoperative pancreatic fistula (CR-POPF) per the International Study Group of Pancreatic Surgery definition. Results: Of the 384 patients (stapler closure, 339; hand-sewn closure, 45) enrolled, 249 developed CR-POPF (grades B and C: 242 and 7 patients, respectively). The rates of grade B and grade C POPF in the stapler group were similar to the corresponding rates in the hand-sewn group (64.6% and 1.5% vs 51.1% and 4.4%, P = .078 and P = .223, respectively). No differences between the stapler and hand-sewn groups were observed regarding the median operation time (207 vs 222 minutes, P = .139), incidence of major complications (16.5% vs 20.0%, P = .559), and mortality (0.2% vs 0%, P = 1.000). The independent risk factors of CR-POPF were abdominal abscess, prolonged operation time, and transection site (P = .004, .006, and .001, respectively). Conclusion: The incidence and severity of CR-POPF by stapler closure of the pancreatic stump were comparable to those associated with hand-sewn closure in MDP in this retrospective cohort. Randomized controlled trials are needed to verify this finding.

Development and application of a spray tip that enables electrocoagulation of a variety of tissues

BackgroundSpray hemostasis is possible using a high-frequency power source from the tip of an electric scalpel; however, the difficulties regarding the uniformity and rapidity of the hemostasis surface remain. This study reports the development of a novel electrocoagulation device tip that can be used in endoscopic and robotic surgeries and can quickly coagulate and hemostat and easily adjust the extent of cauterization and hemostasis while minimizing the depth of thermal injury. MethodsThe safety and efficacy of the hemostatic device were verified in a porcine model. A liver surface transection was conducted in vivo and the rapidity of the hemostatic effect of the device was observed. An extracted stomach, kidney, and liver were cauterized ex vivo by three operators with different surgical skills and the effects were analyzed pathologically. In addition, a sacrificed pig cadaver was used to achieve hemostasis at a renal transection site using the multi-spray endoscope tip. ResultsAn increase in the number of tip terminals expanded the cauterization surface and shortened the cauterization time. In parenchymatous organs, uniform cauterization was possible without increasing the depth of thermal injury. The cauterization depth did not depend on the operator's skill, and the spray coagulation was safe. The variable spray tip allowed for simple hemostasis during open and laparoscopic surgeries. ConclusionsThis novel electrocoagulation device tip can be developed as a forceps that can change the spray range and can be used during laparoscopic and robotic surgeries.

Nerve trunk healing and neuroma formation after nerve transection injury.

The nerve trunk healing process of a transected peripheral nerve trunk is composed of angiogenesis, nerve fiber regeneration, and scarring. Nerve trunk healing and neuroma formation probably share identical molecular mediators and similar regulations. At the nerve transection site, angiogenesis is sufficient and necessary for nerve fiber regeneration. Angiogenesis and nerve fiber regeneration reveal a positive correlation in the early time. Scarring and nerve fiber regeneration show a negative correlation in the late phase. We hypothesize that anti-angiogenesis suppresses neuromas. Subsequently, we provide potential protocols to test our hypothesis. Finally, we recommend employing anti-angiogenic small-molecule protein kinase inhibitors to investigate nerve transection injuries.