Resected Surface Research Articles

Genome-wide microRNA Analysis Identified miR-210-3p Over-expression in Pancreatic Cancer Tissues as a Predictor of their Local Invasiveness.

The severe malignancy of pancreatic ductal adenocarcinoma (PDAC) is mainly due to frequent local invasiveness and distant metastasis. As for local invasiveness, we previously reported that cancer-specific molecular alterations detected on resected PDAC specimen surfaces, so-called molecular surgical margin (MSM) positiveness, were significantly associated with postoperative locoregional recurrence and distant metastasis. However, due to anatomical limitations, achieving adequate surgical margins during pancreatic cancer resection is often challenging. Therefore, predicting local invasiveness based on the primary tumor's gene profile is crucial to avoid positive MSM. Genome-wide miRNA expression profiles were examined and compared between MSM-positive and negative cases. Candidate miRNAs were evaluated in another validation cohort, and their clinicopathological characteristics were examined. Mimic or inhibitor constructs of the candidate miRNA were transfected to PDAC cell lines to evaluate the miRNA function in the pancreatic cancer cell lines and detect the downstream targets. Among some candidates with highly expressed miRNAs in MSM-positive cases by miRNA expression array, recurrence-free survival (RFS) was significantly shorter in the miR-210-3p high expression group (p=0.015). High miR-210-3p was significantly associated with large tumor diameter (p=0.001), anterior invasion positive (p=0.010), and positive lymph node metastasis (p<0.001). miR-210-3p inhibition in PDAC cell lines resulted in decreased proliferation and invasiveness. The iron-sulfur cluster assembly enzyme (ISCU) gene was identified as a target of miR-210-3p. ISCU reduction was significantly observed in PDAC primary tumors with high levels of miR-210-3p, leading to mitochondrial dysfunction in miR-210-3p-overexpressing PDAC cell lines, as demonstrated by glycolysis stress tests. Highly expressed hypoxia-inducible miR-210-3p in primary PDAC tissues induces locally invasive characteristics through mitochondrial dysfunction by suppressing ISCU expression, which may result in poor postoperative RFS outcomes.

The comparative study of temperature rise, time consuming and cut quality among piezosurgery, conventional rotary instruments and Er: YAG laser in apicectomy

ObjectivesThis study aimed to compare the temperature rise, time consuming and cut quality of apicectomy using three different methods.Materials and methodsTwenty-four single-rooted teeth were collected and divided into four groups operating apicectomy with a NINJA tip of a piezoelectric device (G1), a diamond bur with 300,000 rpm (G2), and Er: YAG laser at 200 mJ/ 30 Hz (G3) as well as 250 mJ/ 30 Hz (G4). The temperature elevation and time were recorded and the cut quality was evaluated via stereomicroscope and scanning electronic microscopy (SEM).ResultsThe temperature increases for G1 was significantly higher than for G2. However, there was no significant difference between G1 and G2 with laser groups respectively. The median time for apicectomy was: 100.14s for G1, 22.65s for G2, 33.58s for G3, and 21.80s for G4. G1 is the most time-consuming group and there was no statistically significance in the comparisons with G2, G3 and G4. Cut quality was assessed by crack occurrence, smear layer formation and dentinal tubules exposed. The percentage of cracked teeth in G1 and G2 was 33.33% and for laser groups the percentage was 16.67% each. SEM showed that no smear layer formed and almost all dentinal tubules were exposed on resected surfaces for G3&G4, surfaces from G2 were partly covered by smear layer, and surfaces from G1 were fully covered by smear layer and with no dentinal tubules exposed.ConclusionsEr: YAG laser and conventional rotary instruments were safe and efficient for apicectomy and with a better cut quality when compared with piezoelectric equipment. Er: YAG laser could be a promising technique for apicectomy and further studies are necessary, especially larger sample in vivo investigations, to verify the feasibility of Er: YAG laser in endodontic surgery.

Ex vivo fluorescence-guided resection margin assessment in breast cancer surgery using a topically applied, cathepsin-activatable imaging agent

Up to 40 % of breast cancer patients have a tumor-positive resection margin (TPRM) – defined as cancer cells at the surface of the resected specimen – after breast-conserving surgery (BCS), necessitating re-resection or boost radiation. To prevent these additional treatments, intraoperative near-infrared (NIR) fluorescence imaging with the topically applied, cathepsin-activatable imaging agent AKRO-6qcICG might be used to detect TPRMs and guide additional resection. Here, to validate its performance, the agent is topically applied to all surfaces of freshly resected breast cancer specimens (n = 11 patients) and to 3–5 mm thick tissue slices of the specimens (n = 26 patients). NIR fluorescence images of the resection surfaces and tissue slices are acquired and correlated to final histopathology. AKRO-6qcICG detects TPRMs with a sensitivity, specificity, PVV, and NPV of 100 %, 67 %, 10 %, and 100 %, respectively. On the tissue slices, the fluorescence signal has a median tumor-to-background ratio of 1.8. These findings indicate that topically applied AKRO-6qcICG can visualize TPRMs ex vivo with a high sensitivity and NPV, with sufficient contrast to adjacent healthy breast tissue.

Excision combined with ocular surface reconstruction followed by topical chemotherapy for ocular surface squamous neoplasia.

To investigate the visual prognosis of ocular surface squamous neoplasia (OSSN) after tumor resection and ocular surface reconstruction, and clarify factors that influence recurrence. Retrospective cohort study. Medical records of all patients who underwent surgical treatment for OSSN at our hospital between January 1996 and December 2019 were reviewed. Tumor size/location, histological classification, surgical procedure, intraoperative mitomycin-C use, and postoperative topical 5-fluorouracil (5-FU) administration were examined, and pre and postoperative visual acuity (VA) were compared to elucidate factors that influence disease recurrence. Tumor excision was performed in 70 eyes of 70 cases (43 men, 27 women; average age: 71.6 ± 12.6 years) with dysplasia (8 eyes), carcinoma in situ (26 eyes), and invasive squamous cell carcinoma (36 eyes). Tumors were found in the limbus (N = 59 eyes), palpebral conjunctiva (N = 8 eyes), and from the bulbar to palpebral conjunctiva (N = 3 eyes). Surgical procedures performed were limbal transplantation/keratoepithelioplasty (N = 29 eyes), cultivated oral mucosal epithelial transplantation (N = 3 eyes), and auto-conjunctival epithelium transplantation (N = 2 eyes). Ocular surface was reconstructed using amniotic membrane, donor cornea, or cultivated epithelial sheet. The mean follow-up was 38.6 ± 38.6 months (range, 2 months to 13.8 years). VA postoperatively improved in 25 (61.0%) cases. Recurrence occurred in 19 (27.1%) cases at from 2 to 50 months (median: 12.5 months) postoperative. Uni- and multivariate analyses revealed that presurgical tumor size and postoperative administration of 5-FU were significantly related to recurrence. Combined surgical excision and postoperative topical 5-FU administration effectively prevented OSSN recurrence, and ocular surface reconstruction contributed to improvement of VA.

Individualised compared to off-the-shelf total knee arthroplasty results in lower and less variable patellar tilt.

The purpose of this study was to compare postoperative patellar tilt at 4 months follow-up in a consecutive series of randomised patients that received individualised or off-the-shelf (OTS) primary total knee arthroplasty (TKA). The hypothesis was that patellar tilt would be lower and less variable in patients who received individualised TKA compared to patients who received OTS TKA. A consecutive series of 385 patients randomised (1:1) to receive either OTS TKA or individualised TKA were analysed. Pre- and postoperative radiographs at 4 months were obtained of weight-bearing long leg, anterior-posterior and lateral knee viewsand a skyline view at 30° of flexion. Postoperative patellar tilt was measured between the anterior femoral line and patellar resection surface (β) and the anterior femoral line and mediolateral patellar axis (σ). Postoperative patellar tilt (absolute value) was compared between the individualised and OTS TKA groups based on preoperative phenotypes of their femoral mechanical angle, tibial mechanical angle and hip-knee-ankle angle. Variability in postoperative patellar tilt was compared using the 95% confidence intervals (CIs). Comparisons of baseline patient characteristics revealed no difference between the individualised and OTS TKA groups. Comparison of absolute postoperative patellar tilt revealed significant differences between individualised and OTS TKA (|β|, 1.0° ± 1.0° and 2.5° ± 2.2°,respectively,p < 0.001; |σ|, 1.7° ± 1.6° and 2.8° ± 2.3°,respectively,p < 0.001). The 95% CIof postoperative patellar tilt (|β|) was narrower in patients that received individualised compared to OTS TKA (0.0° to 3.8° and 0.1° to 8.3°, respectively), irrespective of their preoperative phenotype. Patients who underwent individualised TKA had lower and less variable postoperative patellar tilt than those with OTS TKA, irrespective of preoperative phenotype. Individualised TKA allows the decoupling of the tibiofemoral and patellofemoral joints, replicating anatomical trochlear orientation and improving patellar tilt, which could facilitate better clinical outcomes. This study constitutes a part of a larger registered randomised controlled trial comparing patient satisfaction following OTS versus individualised TKA (NCT04460989). Level II.

Influence of age-related bone density changes on primary stability in stemless shoulder arthroplasty: a multi-implant finite element study

BackgroundStemless implants were introduced to prevent some of the stem-related complications associated with the total shoulder arthroplasty. Although general requirements for receiving these implants include good bone quality conditions, little knowledge exists about how bone quality affects implant performance. The goal of this study was to evaluate the influence of age-induced changes in bone density, as a metric of bone quality, in the primary stability of five anatomic stemless shoulder implants using 3D finite element (FE) models. MethodsThe implant designs considered were based on the Global Icon, Sidus, Simpliciti, SMR, and Inhance stemless implants. Shoulder arthroplasties were virtually simulated in Solidworks. The density distributions of 20 subjects from two age groups, 20 to 40 and 60 to 80 years old, were retrieved from medical image data and integrated into three-dimensional FE models of a single humerus geometry, developed in Abaqus, to avoid confounding factors associated with geometric characteristics. For the designs which do not have a solid collar covering the entire bone surface, i.e., the Sidus, Simpliciti, SMR, and Inhance implants, contact and non-contact conditions between the humeral head component and bone were considered. Primary stability was evaluated through the assessment of micromotions at the bone-implant interface considering eight load cases related to rehabilitation activities and demanding tasks. Three research variables, considering 20 μm, 50 μm, and 150 μm as thresholds for osseointegration, were used for a statistical analysis of the results. ResultsThe decreased bone density registered for the 60-80 age group led to larger micromotions at the bone-implant interface when compared to the 20-40 age group. The Global Icon-based and Inhance-based designs were the least sensitive to bone density, whereas the Sidus-based design was the most sensitive to bone density. The establishment of contact between the humeral head component and bone for the implants that do not have a solid collar led to decreased micromotions. DiscussionAlthough the age-induced decline in bone density led to increased micromotions in the FE models, some stemless shoulder implants presented good overall performance regardless of the osseointegration threshold considered, suggesting that age alone may not be a contraindication to anatomic total shoulder arthroplasty. If only primary stability is considered, the results suggested superior performance for the Global Icon-based and Inhance-based designs. Moreover, the humeral head component should contact the resected bone surface when feasible. Further investigation is necessary to combine these results with the long-term performance of the implants and allow more precise recommendations.

A New Proposal for Adequate Resection Margins in Larynx and Hypopharynx Tumor Surgery-Are the RCP Guidelines Feasible?

Resection margins are an important prognostic factor for patients with head and neck cancer. In general, for head and neck surgery, a margin >5 mm is advised by the Royal College of Pathologists. However, this cannot always be achieved during laryngeal and hypopharyngeal surgery. The aim of this study is to identify the resection surfaces and measure the maximum feasible margins per subsite. The clinical relevance of these maximum feasible resection margins were analyzed in this descriptive anatomical study. head and neck surgeons and a pathologist from the Erasmus MC performed a total laryngectomy and laryngopharyngectomy on a head and neck specimen specifically available for research. For a total laryngectomy, resection margins >5 mm were not feasible for the ventral and dorsal resection surface. For a total laryngopharyngectomy, resection margins >5 mm were not feasible for the ventral, dorsal and lateral resection surface. Clear resection margins, defined as a margin >5 mm, are not always feasible in laryngeal and hypopharyngeal surgery, due to the anatomy of the larynx and tumor location. However, striving for a maximum feasible margin is still the main goal. We propose a new guideline for maximum feasible but adequate resection margins in larynx and hypopharynx tumor surgery.

Optimal intersurface stability for unicompartmental femoral component design with two pegs placed on the distal resection surface:5 mm peg length incrementand 10° peg inclination.

The present study aimed to identify the optimal design of the unicompartmental femoral component through parameter analysis and stability evaluation. A finite element (FE) analysis was applied to analyse and adjust the parameter combinations of the anterior tilt angle of the posterior condyle resection surface, the position of the peg, the length of the pegand the inclination angle of the peg, resulting in 10 different FE models. Setting three knee flexion angles of 8.4° (maximum load state during walking), 40° (maximum load state during stair climbing)and 90° (maximum load state during squatting exercise), quantitatively analysing the micromotion values of the bone-prosthesis interfaceand defining a weighted scoring formula to evaluate the stability of different FE models. The validity of the FE analysis was verified using the Digital Image Correlation (DIC) device. The errors between the FE analysis and the DIC test at three flexion angles were 5.6%, 1.7%and 11.1%. The 10 different femoral component design models were measured separately. The FE analysis demonstrated that the design with a 0° anterior tilt angle of the posterior condyle resection surface, both pegs placed on the distal resection surface, lengthened 5 mm pegsand a 10° peg inclination angle provided the best stability. The current study proposed a method for evaluating the stability of the femoral component design. The optimal intersurface stability design of the unicompartmental femoral component was achieved with two pegs placed on the distal resection surface, a 5-mm peg length incrementand a 10° peg inclination. These results might provide a reference for the selection of unicompartmental femoral components in clinical practice and therefore improve the survival rate of future unicompartmental knee arthroplasty. Level III.

BipoJet Scissors as an Alternative to Laser in Lung Wedge Resection.

An important goal in every lung resection is airtight closure of the resected lung surface. This can be achieved with several techniques, including clamp resection, stapler, laser, and various high-frequency methods.By quantitatively measuring the air fistulaacross the resection surface of porcine lungs, two resection techniques were compared in our study: BipoJet dissecting scissors (Aesculap, Inc., Tuttlingen,Germany) and laser (Ceralas HPD®, Biolitec Inc., Jena, Germany). Following a stencil, wedge resections were performed in porcine lungs using water-irrigated bipolar scissors and laser (1350nm, 40watts, non-contact mode). The volumeof the air fistula was then measured. The irrigation technique involved the attachment of an irrigation channel to a pair of standard surgical scissors. Asodium chloride (NaCl) solution was fed at a defined flow rate, along the blades of the scissors onto the parenchyma. This technique was used on a total of 10 specimens each. Somewhat better pneumostasis was achieved with laser resection, though the difference was small and not statistically significant. The flow rate was 124mL/min/cm² after laser resection and 145 mL/min/cm² after using the BipoJet scissors. The difference was not statistically significant.Water irrigation during resection with the BipoJet scissors prevents the temperature in the tissue from exceeding 100°Cthus avoiding tissue carbonization. These scissors offer the following advantages: ease of use, no need to change instruments, no need for staff training, no protective measures, all-in-one incision/coagulation/dissection, low cost, and a clear surgical field due to the irrigation effect. Resection of lung parenchyma, e.g., during resection of metastases, is easier with BipoJet scissors and comparable to laser resection. This was established both experimentally and by resecting lung metastases.

Immunotherapeutic hydrogel for co-delivery of STAT3 siRNA liposomes and lidocaine hydrochloride for postoperative comprehensive management of NSCLC in a single application

Despite standard treatment for non-small cell lung cancer (NSCLC) being surgical resection, cancer recurrence and complications, such as induction of malignant pleural effusion (MPE) and significant postoperative pain, usually result in treatment failure. In this study, an alginate-based hybrid hydrogel (SOG) is developed that can be injected into the resection surface of the lungs during surgery. Briefly, endoplasmic reticulum-modified liposomes (MSLs) pre-loaded with the signal transducer and activator of transcription 3 (STAT3) small interfering RNA and lidocaine hydrochloride are encapsulated in SOG. Once applied, MSLs strongly downregulated STAT3 expression in the tumor microenvironment, resulting in the apoptosis of lung cancer cells and polarization of tumor-associated macrophages towards the M1-like phenotype. Meanwhile, the release of lidocaine hydrochloride (LID) was beneficial for pain relief and natural killer cell activation. Our data demonstrated MSL@LID@SOG not only efficiently inhibited tumor growth but also potently improved the quality of life, including reduced MPE volume and pain relief in orthotopic NSCLC mouse models, even with a single administration. MSL@LID@SOG shows potential for comprehensive clinical management upon tumor resection in NSCLC, and may alter the treatment paradigms for other cancers.

Virtual tumor mapping and margin control with 3-D planning and navigation.

Computer technology-based treatment approaches like intraoperative navigation and intensity-modulated radiation therapy have become important components of state of the art head and neck cancer treatment. Multidirectional exchange of virtual three-dimensional patient data via an interdisciplinary platform allows all medical specialists involved in the patients treatment to take full advantage of these technologies. This review article gives an overview of current technologies and future directions regarding treatment approaches that are based on a virtual, three-dimensional patient specific dataset: storage and exchange of spatial information acquired via intraoperative navigation allow for a highly precise frozen section procedure. In the postoperative setting, virtual reconstruction of the tumor resection surface provides the basis for improved radiation therapy planning and virtual reconstruction of the tumor with integration of molecular findings creates a valuable toolfor postoperative treatment and follow-up. These refinements of established treatment components and novel approaches have the potential to make a major contribution to improving the outcome in head and neck cancer patients.

Thermocoagulation of resection surfaces of parenchymal organs using a new source of ultrahigh frequency energy (experimental study)

Relevance. Modern surgery is characterized by the use of various technical means to perform classical surgical techniques - separation and connection of tissues, hemostasis. The study of the applicability of new surgical devices and the search for technological techniques are an important task.The aim of the study: to evaluate the capabilities of the developed device based on microwave energy for hemostatic coagula­tion of resection surfaces of parenchymal organs.Materials and methods. The method is based on the principle of converting microwave energy into heat when it is absorbed in biological tissue. The choice of the microwave range is due to the higher efficiency of power supply to the heat­ing area. Based on the prototype of a medical microwave complex developed in 2011 for thermal effects on biological tissues (RF Patent 2481080. 2011), a prototype of a microwave coagulator for working with parenchymal organs was created. The device was tested on the paren­chymal organs of large laboratory animals under conditions of preserved and switched off blood flow in various energy supply modes. Tissue samples from coagulated lesions were studied histologically.Results. At the site of exposure of the applicator-coagulator to the parenchymal organ, a zone of coagulation changes appears. A clear dependence of the size of coagulation necrosis on the time and power of exposure was noted. When the blood flow is turned off, the necessary stable hemostasis is achieved by shorter exposure time of the coagulator antenna on the surface of the organ.Conclusions. The most effective and reliable hemostasis is achieved on the liver parenchyma. The use of temporary vascular isolation, especially on the kidneys and spleen, involves a single use of microwave energy to stop bleeding. By changing the power and duration of exposure, it is possible to dose the thermal load on biological tissue with great precision. This adjustment allows you to select the operating mode for each specific case. The obtained results of the experiment of the described system during surgery for the purpose of hemostasis in parenchymal bleeding.

Topography of root-end surface after freehand and three-dimensional-guided apicoectomy procedure: A scanning electron microscope study.

Dentinal microcracks formed during apical resection may lead to increased susceptibility to root fracture and improper sealing of apical preparation that may negatively influence the outcome of endodontic microsurgery. This study was performed to analyze the root-end surface for dentinal microcracks using a scanning electron microscope (SEM) after resection with high-speed bur and trephine drill. Thirty extracted single-rooted maxillary premolar teeth were selected and randomly distributed into two groups (n = 15). Working length was established using a #15 K-type file. Canals were prepared with a rotary Ni-Ti system to size 30/0.06 using endomotor, irrigated with 3% sodium hypochlorite, dried with paper points, and obturated with gutta-percha cones using a single-cone technique. All samples were mounted on preformed molds and poured using a mixture of sawdust and gypsum. In Group A; tungsten carbide bur was used to perform a freehand apicoectomy. In Group B; a trephine drill was used with a three-dimensional guide to perform 3 mm of root resection. Apicoectomy was performed in both groups under a dental operating microscope. Resected root ends were inspected for microcracks using SEM. The Shapiro-Wilk and Mann-Whitney U-test were used for statistical analysis. Microcracks were observed in all samples in both study groups. Trephine drill produced more microcracks on the resected root surface compared to the use of high-speed tungsten carbide bur with a statistically significant difference (P < 0.05). The trephine drill used during targeted endodontic microsurgery produced more microcracks on the resected root dentine surface compared to the high-speed tungsten carbide bur used during freehand apicoectomy.

The First Prospective Study Investigating the Safety and Feasibility of a Spray-Type Adhesion Barrier (AdSpray™) in Minimally Invasive Hepatectomy: An Analysis of 124 Cases at Our Institution.

(1) Background: With the increasing demand for repeat hepatectomy, preventing perihepatic adhesion formation following initial hepatectomy is crucial. Adhesion-preventative barriers, like the new spray-type AdSprayTM (Terumo Corporation, Tokyo, Japan), have been proposed to reduce adhesion risk. However, data on their safety in minimally invasive hepatectomy (MIH) remain scarce. This is the first prospective study to evaluate the safety and feasibility of AdSprayTM in MIH. (2) Methods: A total of 124 patients who underwent MIH with AdSprayTM and 20 controls were analyzed. Subgroup analysis according to the AdSpray™ application area was conducted. Major complications were assessed using the Clavien-Dindo classification. Moreover, intraperitoneal pressure during AdSpray™ application was monitored in 20 cases. (3) Results: Major complications occurred in 6.4% of the patients, which was comparable to that in open hepatectomy. Intraperitoneal pressure remained stable below 12 mmHg during AdSpray™ application without any complications. No significant difference in complication rates was observed among subgroups. However, a potential increase in intra-abdominal abscess formation was suspected with AdSpray™ application to the resected liver surfaces. (4) Conclusions: AdSpray™ can be safely used in MIH; however, further research is needed to confirm the appropriacy of using AdSpray™, particularly over resected liver surfaces. Overall, AdSpray™ is a promising tool for enhancing the safety of MIH.

A127 ENDOSCOPIC MUCOSAL RESECTION WITH HYBRID-ARGON PLASMA ABLATION TO PREVENT RECURRENCE OF 20 MM NON-PEDUNCULATED COLORECTAL POLYPS: A MULTI-CENTER PROSPECTIVE CLINICAL STUDY

Abstract Background Endoscopic mucosal resection (EMR) is the mainstay of therapy for non-pedunculated colorectal polyps 20 mm or larger. Post EMR recurrence rates are about 15% if no margin ablation technique is used. Aims Study aim was to evaluate recurrence rates if hybrid Argon Plasma Coagulation ablation (h-APC) is routinely used after the EMR to ablate the margins, base and vessels. Methods A prospective multi-center study including adult patients (18-89 years) undergoing EMR of non-pedunculated colorectal polyps 20 mm or larger was conducted. h-APC was used to ablate all post EMR margins and to ablate the post EMR resection surface and visible submucosal vessels. The primary outcome was the biopsy proven recurrence rate at the first follow-up colonoscopy (4-6 months after EMR). All the resection sites were visually inspected, and biopsies were obtained from the EMR scar. Secondary outcomes included technical success and complication rates. Results A total of 220 EMRs were performed during the study for h-APC ablation of non-pedunculated colorectal polyps, with a size of ≥20 mm. The average size of the polyps included in the study was 35.7 mm (ranging from 20 mm to 100 mm). Among all resected polyps, 16.8% were sessile serrated lesions (SSL), while 66.3% were adenomas. Additionally, 4 cases of cancer were in the study. The application of hot snare EMR with h-APC ablation was technically successful and completed for all cases. The mean duration of the EMR procedure was 19.6 minutes, ranging from 2.3 to 103 minutes, while the mean duration of h-APC ablation was 6.4 minutes, ranging from 1 to 65 minutes. A total of 147 EMRs with follow up examination (57 EMR involving lesions 40mm or larger) are available currently. The overall recurrence rate was 1.3% (2 out of 147 cases). For cases where complete base ablation was achieved, there was a 0% recurrence rate, including lesions 40mm or larger. For lesions measuring 40mm or larger, the recurrence rate was 1.8% (1 out of 54 cases). Out of the 220 total EMRs conducted, perforations were observed in 0.9% (2 cases, managed conservatively with antibiotics only), and clinically significant bleeding occurred in 2.3% (5 cases). In particular, clinically significant bleeding was noted in 2.3% (4 out of 167 cases) of lesions without clipping and in 4.0% (4 out of 99 cases) for right-sided lesions without clipping. Conclusions In this multicenter study EMR in combination with h-APC demonstrated a high technical success rate with low complication rates and showed very low post EMR recurrence in the preliminary data analysis. Funding Agencies Erbe

A Prospective Analysis of the Effects of a Powder-Type Hemostatic Agent on the Short-Term Outcomes after Liver Resection.

Background and Objectives: Postoperative bleeding is a significant cause of morbidity and mortality following liver resection. Therefore, it is crucial to minimize bleeding during liver resection and effectively manage it when it occurs. Arista® AH (Becton, Dickinson and Company, Franklin Lakes, NJ, USA) is a microporous polysaccharide hemosphere (MPH), a new plant-derived polysaccharide powder hemostat that can be applied to the entire surgical field. This study prospectively assessed the effectiveness of Arista for bleeding control when applied intraoperatively to the liver resection surface. Materials and Methods: Data were collected at Seoul National University Bundang Hospital for patients who underwent liver resection owing to malignant hepatocellular carcinoma or benign liver diseases. We compared the outcomes between 45 patients managed with Arista® AH (data were prospectively collected between September 2022 and May 2023) and 156 patients managed without the use of Arista® AH (data were retrospectively collected between January 2021 and December 2021). Results: There were no significant differences in patient characteristics between the two groups. The estimated blood loss (EBL) was significantly lower in the Arista® AH group compared with the control group (495.56 ± 672.7 mL vs. 691.9 ± 777.5 mL, p = 0.049). The mean postoperative hospital stay was significantly shorter in the Arista® AH group (5.93 ± 1.88 days vs. 6.94 ± 4.17 days, p = 0.024). The time to Jackson-Pratt drain removal was also significantly shorter in the Arista® AH group (4.64 ± 1.31 days vs. 5.30 ± 2.87 days, p = 0.030). The patient subgroup was divided into four categories based on the type of resection and the presence or absence of cirrhosis. Within the subgroup of major resections in non-cirrhotic patients, the Arista® AH group demonstrated significantly better outcomes compared to the control group, showed lower EBL, reduced need for blood transfusions, decreased volume of drain fluid collected within 48 h, earlier removal of drains, and shorter hospital stays. In contrast, for the other subgroups such as minor resection (both non-cirrhotic and cirrhotic) and major resection with cirrhosis, the differences between the Arista® AH and control groups in various parameters like EBL, blood transfusion rates, drain fluid volume, time to drain removal, and duration of hospital stay were not statistically significant. Conclusions: Arista® AH significantly improved intraoperative blood management and postoperative recovery in patients undergoing liver resection, particularly in non-cirrhotic patients who underwent major resection.

Prevention of parenchymal adhesions by applying tabotamp fibrillar® on liver resection surfaces in two-stage hepatectomies

Prevention of parenchymal adhesions by applying tabotamp fibrillar® on liver resection surfaces in two-stage hepatectomies

"Boot Sign" of Anterior Femoral Condylar Resectional Shape during Total Knee Arthroplasty Is More Frequent in Asian Patients.

There is lack of intraoperative consensus on the distal femur anterior resected surface shape that allows reliable rotational alignment assessment during total knee arthroplasty (TKA). We aimed to evaluate the ratio and prevalence of anterior femoral resection surface intraoperatively. The study included 234 osteoarthritis patients with varus knees and not valgus knees or deformities. After conventional medial parapatellar approach, measured resection technique based on the mechanical axis of the femur and preoperative TEA-PCA angle on CT with anterior reference was used among all the patients. The anteroposterior (AP) lengths after distal femoral resection were measured as the femoral lateral AP (FLAP) and femoral medial AP (FMAP) lengths. Based on the medial (MD) and lateral condyle (LD) vertical distance ratios of the femur anterior resected surface, the groups were classified into "boot sign", "grand-piano", and "butterfly sign" groups. For comparison of the mean values, the data were assessed for normality with the Shapiro-Wilk test. One-way ANOVA with post hoc analysis using Tukey's honestly significant difference (HSD) test was used to compare the mean values among the groups. The correlations between the MD/LD and variables were analyzed using the Pearson correlation coefficient. Linear regression analyses were used to find the associated factors to the anterior femoral resection surface shape. Mean intraoperative femoral rotation and distal femoral cutting angles were 4.9° ± 1.2 and valgus 5.0° ± 0.7, respectively. Mean FLAP was 52.9 ± 4.2 mm. Mean MD/LD (0.61 ± 0.13) was lower than that of typical "grand-piano sign". The morphological shape incidence of the "boot sign" was 62.4%. In the "boot sign" group, the FLAP was found to be smaller than that in the other groups (52.4 ± 4.2 vs. 53.7 ± 4.2 vs. 54.9 ± 2.7; p = 0.02), while the intraoperative femoral rotation angle was found to be larger than in the other groups (5.0 ± 1.2 vs. 4.6 ± 1.1 vs. 4.7 ± 1.2; p = 0.039). The MD/LD-associated factors were FLAP, intraoperative femoral rotation, and distal femoral cutting angles (R2 = 0.268). The femur anterior resection surface shape in TKA was found in the "boot sign" rather than the "grand-piano sign" in Korean ethnics owing to an asymmetric morphology of femoral condyles. Ethnic differences, including distal femoral morphology, should be considered for assessment of the femoral rotation angle using the femur anterior resection surface shape.

An in vitro assessment of cytotoxicity and genotoxicity of root repair materials.

The success of the root-end procedure depends on the regeneration of the functional periodontal attachment system, including the cementum on the resected root-end surface, periodontal ligament (PDL), and alveolar bone. As root end filling materials remain in close contact with live periapical tissues, they may influence the endodontic treatment outcome. To assess and compare the cytotoxicity and genotoxicity of three root repair materials, mineral trioxide aggregate (MTA), endosequence, and geristore in human-cultured periodontal ligament fibroblasts. Cultured human periodontal ligament fibroblasts of the third passage were used in the study. They were placed in contact with the root repair materials. The cytotoxic effect on PDL fibroblasts was determined by (3-(4,5-dimethylthiazol-2-yl)-2,5-tetrazolium bromide) assay after 24 hours and 48 hours intervals. Cell viability was determined using an inverted phase contrast microscope. The genotoxic effect on the periodontal fibroblast cells was determined by comet assay using imaging software. Data were analyzed using Tukey's multiple comparison test and Dunnett's multiple test. All the test materials showed higher cytotoxicity and genotoxicity at the 48th hour interval with a statistically significant difference from the control group (P < 0.05). MTA was shown to be least cytotoxic and genotoxic to PDL fibroblasts, followed by endosequence root repair material and geristore at 24 hour and 48 hour intervals. The cytotoxicity and genotoxicity of MTA were the least compared to endosequence and geristore on human-cultured PDL fibroblasts.

Intraoperative electrochemotherapy of the posterior resection surface after pancreaticoduodenectomy: Preliminary results of a hybrid approach treatment of pancreatic cancer

BackgroundDespite extensive research in recent decades, pancreatic cancer continues to be among the most lethal forms of cancer, with no substantial increase in survival rates. Local recurrences account for approximately 30 per cent of all disease recurrences. With the intent to improve survival, we designed a novel, hybrid treatment strategy consisting of surgical resection and additional intraoperative electrochemotherapy of the posterior resection surface. We present the study protocols and preliminary findings of a prospective pilot study investigating this treatment approach. MethodsConsenting patients with resectable pancreatic head ductal adenocarcinoma who met the inclusion criteria were enrolled in the study. After surgical resection, electrochemotherapy with bleomycin was performed using plate electrodes to cover the area between anatomical landmarks. ResultsElectrochemotherapy of the posterior resection surface was feasible in all 7 patients. We observed pancreatic fistula grade B in only one patient; all other noted complications were Clavien-Dindo grade 2 or less. The hospital mortality was 0%. ConclusionsOur preliminary results suggest that a hybrid approach combining surgery with intraoperative electrochemotherapy is safe and feasible.