Implantation Of Foreign Material Research Articles

FactorXI Inhibitors: A New Horizon in Anticoagulation Therapy.

Anticoagulation therapy has undergone significant evolution, marked by the emergence of direct oral anticoagulants with distinct advantages. Despite these advancements, challenges persist in managing residual thrombotic and bleeding risks, particularly among vulnerable populations. The pursuit of alternative drugs has honed in on factorXI/XIa inhibitors. This comprehensive review delves into several key aspects regarding this new target: (i) the role of factorXI in the coagulation cascade; (ii) the genetic evidence and pathophysiologic rationale supporting factorXI inhibition as a therapeutic target; (iii) an exploration of the various types of factorXI/XIa inhibitors currently under investigation; (iv) potential applications of these medications, spanning thromboprophylaxis after orthopedic surgery, stroke prevention in atrial fibrillation, secondary prevention after acute coronary syndrome, non-cardioembolic stroke, thromboprophylaxis after foreign material implantation, end-stage renal disease, and patients with cancer; and (v) an overview of ongoing studies, recent findings, and the future trajectory of research into these drugs.

IMPLANTS: DON'T LET THE BACTERIA GROW!

The Global Burden of Disease Study 2019 showed a 33.4% increase in fractures and a 65.3% increase in Years lived with disability (YLD) since 1990. Although the overall rate of fracture related infection (FRI) is low, it increases to 30% in complex fractures. In addition, the implantation of foreign materials, such as fracture stabilizing implants, decreases the number of bacteria needed to cause an infection. Then, when infections do occur, they are difficult to treat and often require multiple surgeries to heal. The bacteria can persist in the canaliculi of the bony tissue, in cells, in a biofilm on material or necrotic bone or in abscess communities. In the last decades, different approaches have been pursued to modify biomaterials as well as implant surface and to develop antimicrobial surfaces or local drug release strategies. This talk will give an introduction to the problem of bony and implant associated infections and presents the development and preclinical (as well as clinical) studies of two approaches for local drug delivery.

Calvarial vault remodeling including pterional decompression for the treatment of nonsyndromic scaphocephaly patients: technical note and retrospective case series.

Surgical techniques to correct scaphocephaly often rely on the implantation of foreign material and/or postoperative helmet therapy and possibly result in minimal correction of frontal bossing. Moreover, foreign material and helmet therapy are associated with extra medical care and financial costs. Frontal bossing is perceived as a prominent, disfiguring feature of scaphocephaly. Herein, authors present the results of a total cranial vault remodeling technique that corrects scaphocephaly features without relying on foreign material or postoperative helmet therapy. It includes frontal release and pterional decompression, which aim to correct frontal bossing. All patients who had been operated on for isolated scaphocephaly at a single institution between January 2011 and December 2020 were included in this retrospective review. Operation time, transfusion volume, hospital stay, complications, cephalic index (CI), and bossing angle (BA) were analyzed. Sixty-five patients with nonsyndromic scaphocephaly were included in this analysis. Imaging to calculate the CI and BA preoperatively, immediately postoperatively, and 1 year postoperatively was available in 22 and 20 patients, respectively. The mean CI increased from 69.2% preoperatively to 74.6% postoperatively and 75.5% 1 year postoperatively. The mean BA decreased from 114.5° preoperatively to 111.6° postoperatively and 108.9° 1 year postoperatively. The mean operating time was 2 hours 4 minutes, and the median blood transfusion volume was 100 ml. There were no major complications or reoperations. The described total cranial vault remodeling technique is a safe procedure that mitigates total treatment burden, as no helmet therapy or implantation of foreign material is needed. It is effective in correcting CI and results in significant frontal bossing correction. The latter is attributed to a distinctive feature of the technique: frontal release and pterional decompression.

Metal hypersensitivity in hip, knee and spine surgery.

The number of implanted joint prostheses and damaged spinal components is steadily increasing. At the same time, rejection of the implanted material is observed in operated patients, which manifests itself in both skin and general reactions, as well as loosening and earlier wear of implanted prostheses, which was previously referred to as aseptic reactions. However, it has been shown that in a significant proportion of patients, rejection of implanted material may be caused by hypersensitivity to a specific metal. For this reason, patients qualified for implantation of foreign material, mainly nickel, titanium, chromium, molybdenum, and other alloys, should be subjected to allergy tests to detect possible risks in the form of metal sensitivity reactions.

Postoperative imaging of the musculoskeletal system- spine

Die Bildgebung der postoperativen Wirbelsäule hat im Wesentlichen zwei Aufgaben: Sie dient der Kontrolle des operativen Erfolgs und der Identifikation von Komplikationen. Dafür stehen die konventionelle Röntgenaufnahme, Computertomographie (CT), Myelographie und Magnetresonanztomographie (MRT) zur Verfügung. Unter Berücksichtigung der präoperativen Situation, der durchgeführten Operation und der postoperativen Beschwerdekonstellation ist es Aufgabe der Radiologinnen und Radiologen, die passende Modalität für eine suffiziente Diagnostik zu wählen. Insbesondere der Zustand nach Implantation von Fremdmaterial bedeutet eine technische Herausforderung im Rahmen der Bildakquisition. In der Befundung sehen sich die Radiologinnen und Radiologen mit der Aufgabe konfrontiert, zwischen natürlichen, zu erwartenden postoperativen Veränderungen und relevanten Komplikationen zu differenzieren. Ein reger Austausch mit Patientinnen und Patienten und zuweisenden Klinikerinnen und Klinikern ist dabei unerlässlich. Insbesondere klinische Hinweise auf einen Infekt, neue oder deutliche progrediente neurologische Ausfallserscheinungen und das Konus-Kauda-Syndrom erfordern eine zeitnahe Diagnosestellung, um eine rasche Therapieeinleitung zu gewährleisten.

Surgical Treatment of Bone Sarcoma

Simple SummaryEven today, a malignant bone tumor is still a threatening condition for the patient. Such tumors are difficult to treat and they require an interdisciplinary approach to ensure the best possible outcome. This review article provides an overview of the three dominating bone sarcoma entities: osteosarcoma, chondrosarcoma, and Ewing sarcoma. Their prognoses and main pillars of treatment (chemotherapy, radiotherapy, surgery) are laid out with a special focus on the surgical management of this condition. Five cases are described to illustrate different surgical strategies such as biological reconstruction and implantation of a megaprosthesis. Finally, an outline of future developments in the field of tumor surgery is presented with a special focus on technical innovations to help improve surgical outcome and implant survival.Bone sarcomas are rare primary malignant mesenchymal bone tumors. The three main entities are osteosarcoma, chondrosarcoma, and Ewing sarcoma. While prognosis has improved for affected patients over the past decades, bone sarcomas are still critical conditions that require an interdisciplinary diagnostic and therapeutic approach. While radiotherapy plays a role especially in Ewing sarcoma and chemotherapy in Ewing sarcoma and osteosarcoma, surgery remains the main pillar of treatment in all three entities. After complete tumor resection, the created bone defects need to be reconstructed. Possible strategies are implantation of allografts or autografts including vascularized bone grafts (e.g., of the fibula). Around the knee joint, rotationplasty can be performed or, as an alternative, the implantation of (expandable) megaprostheses can be performed. Challenges still associated with the implantation of foreign materials are aseptic loosening and infection. Future improvements may come with advances in 3D printing of individualized resection blades/implants, thus also securing safe tumor resection margins while at the same time shortening the required surgical time. Faster osseointegration and lower infection rates may possibly be achieved through more elaborate implant surface structures.

Readmissions after elective orthopedic surgery in a comprehensive co-management care system\u2014a retrospective analysis

BackgroundNo surgical intervention is without risk. Readmissions and reoperations after elective orthopedic surgery are common and are also stressful for the patient. It has been shown that a comprehensive ortho-medical co-management model decreases readmission rates in older patients suffering from hip fracture; but it is still unclear if this also applies to elective orthopedic surgery. The aim of the current study was to determine the proportion of unplanned readmissions or returns to operating room (for any reason) across a broad elective orthopedic population within 90 days after elective surgery. All cases took place in a tertiary care center using co-management care and were also assessed for risk factors leading to readmission or unplanned return to operating room (UROR).MethodsIn this observational study, 1295 patients undergoing elective orthopedic surgery between 2015 and 2017 at a tertiary care center in Switzerland were investigated. The proportion of reoperations and readmissions within 90 days was measured, and possible risk factors for reoperation or readmission were identified using logistic regression.ResultsIn our cohort, 3.2% (42 of 1295 patients) had an UROR or readmission. Sixteen patients were readmitted without requiring further surgery—nine of which due to medical and seven to surgical reasons. Patient-related factors associated with UROR and readmission were older age (67 vs. 60 years; p = 0.014), and American Society of Anesthesiologists physical status (ASA PS) score ≥ 3 (43% vs. 18%; p < 0.001). Surgery-related factors were: implantation of foreign material (62% vs. 33%; p < 0.001), duration of operation (76 min. vs. 60 min; p < 0.001), and spine surgery (57% vs. 17%; p < 0.001). Notably, only spine surgery was also found to be independent risk factor.ConclusionRates of UROR during initial hospitalization and readmission were lower in the current study than described in the literature. However, several comorbidities and surgery-related risk factors were found to be associated with these events. Although no surgery is without risk, known threats should be reduced and every effort undertaken to minimize complications in high-risk populations. Further prospective controlled research is needed to investigate the potential benefits of a co-management model in elective orthopedic surgery.

Nasal Septal Perforation Closure by "Sandwich Grafts": Technique, Initial Results.

Nasal septal perforation closure represents a considerable surgical challenge. Many techniques rely on the implantation of foreign materials that pose a persisting threat of infection. The authors have identified a reliable technique closing septal perforations by an autologous "sandwich graft." It is layered around a piece of auricular cartilage, covered with temporal fascia, thus emulating the physiological layers of the nasal septum. Finally, the prepared graft is then sewn into the perforation in an underlay technique and kept in place by septal splints for 4 weeks. The technique is easily feasible and strives to reconstruct the nasal as physiological as possible. The data obtained from a case series of 11 patients highlights the efficacy of the technique.

Approximate Optimization Study of Light Curing Waterborne Polyurethane Materials for the Construction of 3D Printed Cytocompatible Cartilage Scaffolds.

Articular cartilage, which is a white transparent tissue with 1–2 mm thickness, is located in the interface between the two hard bones. The main functions of articular cartilage are stress transmission, absorption, and friction reduction. The cartilage cannot be repaired and regenerated once it has been damaged, and it needs to be replaced by artificial joints. Many approaches, such as artificial joint replacement, hyaluronic acid injection, microfracture surgery and cartilage tissue engineering have been applied in clinical treatment. Basically, some of these approaches are foreign material implantation for joint replacement to reach the goal of pain reduction and mechanism support. This study demonstrated another frontier in the research of cartilage reconstruction by applying regeneration medicine additive manufacturing (3D Printing) and stem cell technology. Light curing materials have been modified and tested to be printable and cytocompatible for stem cells in this research. Design of experiments (DOE) is adapted in this investigation to search for the optimal manufacturing parameter for biocompatible scaffold fabrication and stem cell attachment and growth. Based on the results, an optimal working process of biocompatible and printable scaffolds for cartilage regeneration is reported. We expect this study will facilitate the development of cartilage tissue engineering.

HeRO® graft: technical application and clinical experience in 73cases

Zunehmendes Alter, Komorbiditäten und die Dauer der chronischen Dialysepflichtigkeit erschweren die Anlage und den Erhalt eines funktionierenden Gefäßzugangs bei Patienten mit terminaler Niereninsuffizienz. Dabei steigt durch zentralvenöse Katheter und kardiologische bzw. onkologische Eingriffe das Risiko einer zentralen Stenose bzw. Okklusion. Die Implantation des Hemodialysis-Reliable-Outflow(HeRO®)-Grafts (Merit Medical Systems Inc., South Jordan, UT, USA) ist ein inzwischen etabliertes kombiniert chirurgisch/interventionelles Verfahren zur Wiederherstellung des stenosierten oder okkludierten venösen Abstroms. Hierdurch kann der Gefäßzugang an der oberen Extremität erhalten bleiben und die wichtige Gefäßressource der unteren Extremität geschont werden. In unserem Zentrum wurden seit 2013 insgesamt 73 Grafts erfolgreich mit steigendem Bedarf implantiert. Der operative Eingriff ist bei uns ein etabliertes und risikoarmes Verfahren geworden. Nach der Implantation ist bei akuter Thrombosierung jedoch 2‑ bis 3‑mal jährlich eine Reintervention erforderlich. Entsprechende Erfahrung vorausgesetzt, sind diese Revisionseingriffe technisch einfach durchzuführen. Bei vollständiger Okklusion der zentralvenösen Strombahn im Bereich der V. cava superior, die nicht durch den HeRO®-Graft passiert werden kann, ist ein Kombinationseingriff mit dem Surfacer®-Sytem (Inside-out-Verfahren) möglich und sinnvoll. Der HeRO®-Graft kann bei Bedarf an eine früh punktierbare Prothese angeschlossen werden. Hierdurch können passagere Dialysekatheter vollständig umgangen werden. Trotz steigender Zahl der HeRO®-Graft-Implantationen bleibt diese Option in unserem Zentrum ein Reserveverfahren. Die interventionellen Verfahren ohne Implantation von Fremdmaterial sollten zunächst ausgeschöpft und etablierte gefäßchirurgische Alternativen (wie beispielsweise der V.-jugularis-Anschluss) vorrangig durchgeführt werden.

In vitro investigation of an intracranial flow diverter with a fibrin-based, hemostasis mimicking, nanocoating

Flow diversion aims at treatment of intracranial aneurysms via vessel remodeling mechanisms, avoiding the implantation of foreign materials into the aneurysm sack. However, complex implantation procedure, high metal surface and hemodynamic disturbance still pose a risk for thromboembolic complications in the clinical praxis. A novel fibrin and heparin based nano coating considered as a hemocompatible scaffold for neointimal formation was investigated regarding thrombogenicity and endothelialization. The fibrin-heparin coating was compared to a bare metal as well as fibrin- or heparin-coated flow diverters. The implants were tested separately in regard to inflammation and coagulation markers in two different in vitro hemocompatibility models conducted with human whole blood (n = 5). Endothelialization was investigated through a novel dynamic in vitro cell seeding model containing primary human cells with subsequent viability assay. It was demonstrated that platelet loss and platelet activation triggered by presence of a bare metal stent could be significantly reduced by applying the fibrin-heparin, fibrin and heparin coating. Viability of endothelial cells after proliferation was similar in fibrin-heparin compared to bare metal implants, with a slight, non-significant improvement observed in the fibrin-heparin group. The results suggest that the presented nanocoating has the potential to reduce thromboembolic complications in a clinical setting. Though the new model allowed for endothelial cell proliferation under flow conditions, a higher number of samples is required to assess a possible effect of the coating.

Sodium Butyrate Downregulates Implant-Induced Inflammation in Mice.

Sodium butyrate (NaBu), a histone deacetylase inhibitor, has shown to exert beneficial actions attenuating inflammation in a number of intestinal and extra-intestinal diseases. However, the effects of NaBu on persistent inflammatory processes as in a response to implantation of foreign material have not been investigated. Synthetic matrix of polyether-polyurethane sponge was implanted in mice's subcutaneous layer of the dorsal region, and the animals were treated daily with oral administration of NaBu (100mg/kg). After 7days, the implants were removed and processed for assessment of inflammatory markers. Butyrate treatment caused a significant attenuation of neutrophil and macrophage infiltration in implants, which was reflected by the reduction of myeloperoxidase and N-acetyl-β-D-glucosaminidase activities, respectively. Similar reduction was observed in intra-implants nitrite levels of NaBu-treated mice. NaBu treatment was also able to decrease mast cell recruitment/activation and the levels of CXCL1, CCL2, IL-6, TNF-ɑ, and TGF-β1 in the implants but did not alter the levels of IL-10. In addition, NaBu administration decreased the concentration of proteins p65 and p50 in the nucleus as compared with the cytoplasm by western blot analysis. This result suggests that treatment with NaBu inhibited the NF-κB pathway. The circulating levels of TNF-ɑ and TGF-β1 were also attenuated by NaBu. Persistent inflammation at sites of implanted devices very often impairs their functionality; therefore, our findings suggest that NaBu holds potential therapeutic value to control this adverse response to biomedical implants.

A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection.

Pseudomonas aeruginosa (P. aeruginosa) is a major nosocomial pathogen of increasing relevance to human health and disease, particularly in the setting of chronic wound infections in diabetic and hospitalized patients. There is an urgent need for chronic infection models to aid in the investigation of wound pathogenesis and the development of new therapies against this pathogen. Here, we describe a protocol that uses delayed inoculation 24 hours after full-thickness excisional wounding. The infection of the provisional wound matrix present at this time forestalls either rapid clearance or dissemination of infection and instead establishes chronic infection lasting 7-10 days without the need for implantation of foreign materials or immune suppression. This protocol mimics a typical temporal course of post-operative infection in humans. The use of a luminescent P. aeruginosa strain (PAO1:lux) allows for quantitative daily assessment of bacterial burden for P. aeruginosa wound infections. This novel model may be a useful tool in the investigation of bacterial pathogenesis and the development of new therapies for chronic P. aeruginosa wound infections.

The Immune Response to Chronic Pseudomonas aeruginosa Wound Infection in Immunocompetent Mice.

Objective: Our goal was to develop a chronic wound model in mice that avoids implantation of foreign material or impaired immunity and to use this to characterize the local and systemic immune response associated with Pseudomonas aeruginosa infection. Approach: We generated bilateral full-thickness dermal wounds in healthy 10-12-week-old C57Bl6 mice. We waited 24 h to inoculate the developing wound eschar at these sites. We performed careful titration experiments with luminescent strains of P. aeruginosa to identify bacterial inoculation concentrations that consistently established stable infections in these animals. We performed flow cytometry-based immunophenotyping of immune cell infiltrates at the wound site, spleen, and draining lymph nodes over time. Finally, we compared inflammatory responses seen in wound inoculation with planktonic bacteria, preformed biofilm, and heat-killed (HK) P. aeruginosa. Results: Using this delayed inoculation model and 7.5 ± 2.5 × 102 CFU/mL of PAO1 we consistently established stable infections that lasted at 10 days in duration. During early infection, we detected a strong upregulation of inflammatory cytokines and neutrophil infiltration at the wound site, while natural killer (NK) cells and dendritic cells (DCs) were reduced. At the systemic level, only plasmacytoid DCs were increased early in infection. During later stages, there was systemic upregulation of B cells, T cells, and macrophages, whereas NK cells and interferon killer DCs were reduced. Infections with P. aeruginosa biofilms were not more virulent than infections with planktonic P. aeruginosa, whereas treatment with HK P. aeruginosa only induces a short-term inflammatory state. Innovation: We describe a versatile wound model of chronic P. aeruginosa infection that lasts 10 days without causing sepsis or other excessive morbidity. Conclusion: This model may facilitate the study of chronic wound infections in immunocompetent mice. Our findings also highlight the induction of early innate immune cell populations during P. aeruginosa infection.

Role of the captured retroviral envelope syncytin-B gene in the fusion of osteoclast and giant cell precursors and in bone resorption, analyzed ex vivo and in vivo in syncytin-B knockout mice

Syncytin-A and -B are envelope genes of retroviral origin that have been captured in evolution for a role in placentation. They trigger cell-cell fusion and were shown to be essential for the formation of the syncytiotrophoblast layer during mouse placenta formation. Syncytin-A and -B expression has been described in other tissues and their highly fusogenic properties suggested that they might be involved in the fusion of other cell types. Here, taking advantage of mice knocked out for syncytin-B, SynB−/− mice, we investigated the potential role of syncytin-B in the fusion of cells from the monocyte/macrophage lineage into multinucleated osteoclasts (OCs) -in bone- or multinucleated giant cells -in soft tissues. In ex vivo experiments, a significant reduction in fusion index and in the number of multinucleated OCs and giant cells was observed as soon as Day3 in SynB−/− as compared to wild-type cell cultures. Interestingly, the number of nuclei per multinucleated OC or giant cell remained unchanged. These results, together with the demonstration that syncytin-B expression is maximal in the first 2 days of OC differentiation, argue for syncytin-B playing a role in the fusion of OC and giant cell mononucleated precursors, at initial stages. Finally, ex vivo, the observed reduction in multinucleated OC number had no impact on the expression of OC differentiation markers, and a dentin resorption assay did not evidence any difference in the osteoclastic resorption activity, suggesting that syncytin-B is not required for OC activity. In vivo, syncytin-B was found to be expressed in the periosteum of embryos at embryonic day 16.5, where TRAP-positive cells were observed. Yet, in adults, no significant reduction in OC number or alteration in bone phenotype was observed in SynB−/− mice. In addition, SynB−/− mice did not show any change in the number of foreign body giant cells (FBGCs) that formed in response to implantation of foreign material, as compared to wild-type mice. Altogether the results suggest that in addition to its essential role in placenta formation, syncytin-B plays a role in OCs and macrophage fusion; yet it is not essential in vivo for OC and FBGC formation, or maintenance of bone homeostasis, at least under the conditions tested.

Detailed standardized protocol to prevent cerebrospinal fluid shunt infection.

While cerebrospinal fluid (CSF) shunt surgery plays an essential role in the treatment of hydrocephalus, postoperative infection due to the implantation of foreign materials is still one of the most common and potentially serious complications of this procedure. Because no previously reported protocol has been proven to prevent postoperative infection after CSF shunt surgeries in adults, the authors investigated the effectiveness of a protocol introduced in their institution. A detailed standardized surgical protocol to prevent infection in patients undergoing CSF shunt surgeries was introduced in the authors' institution in December 2011. The protocol included a series of detailed rules regarding the surgical procedure, the surgical environment to minimize contamination from air, double gloving, local injection of antibiotics, and postoperative management. The rate of CSF shunt infection during the 3 years after surgery before and after implementation of the protocol was compared in patients undergoing their first CSF shunt surgeries. The inclusion periods were from January 2006 to November 2011 for the preprotocol group and from December 2011 to December 2014 for the postprotocol group. The study included 124 preprotocol patients and 52 postprotocol patients. The mean patient age was 59 years in both groups, ranging from 40 days to 88 years. Comparison of patient background factors, including known risk factors for surgical site infections, showed no significant difference between the patient groups before and after implementation of the protocol. While 9 patients (7.3%) developed shunt infections before protocol implementation, no shunt infections (0%) were observed in patients who underwent surgery after protocol implementation. The difference was statistically significant (p = 0.047). The authors' detailed protocol for CSF shunt surgeries was effective in preventing postoperative infection regardless of patient age.

Postoperative kinetics of common inflammatory biomarkers after congenital heart defect procedures with extracorporeal circulation in children.

Extracorporeal circulation is associated with systemic inflammatory response syndrome. Therefore, the diagnosis of infection should be differentiated from a typical postoperative course. The aim of the study was to evaluate the kinetics of inflammatory biomarkers in children in the first days after cardiac surgery with extracorporeal circulation. Prospective data were collected from 51 consecutive children referred for surgical treatment in Department of Paediatric Cardiac Surgery, St. Adalbertus Hospital in Gdańsk, between February and August 2015. Blood samples were collected on the first, second, and third postoperative days and sent to the institutional laboratory for routine investigations: white blood cell count, serum C-reactive protein (CRP) and procalcitonin concentrations. The highest levels of procalcitonin were on the first postoperative day (median 3.53 ng/mL), although the peak values of CRP concentration and white blood cell count were on the second postoperative day (96 mg/L and 17.3 G/L). In the group of patients with foreign material implantation (Contegra® or Gore-Tex®), the higher values of procalcitonin concentration and white blood cell count were measured in the subsequent postoperative days. The kinetics of analysed inflammatory biomarkers on the first days after cardiac surgery for congenital heart disease in children have different characteristics. The knowledge about the kinetics of inflammatory biomarkers could be useful in determining the possibility of evolving infections in the early postoperative period.

In-vivo monitoring of infection via implantable microsensors: a pilot study.

The most common complication after implantation of foreign material is infection, leading to implant failure and severe patient discomfort. Smoldering-infections proceed inapparently and might not get verified by radiological diagnostics. Early identification of this type of infection might significantly reduce the rate of complications. Therefore, we manufactured a microsensor strip in a hybrid of thin-film and laminate technology in a wafer-level process. It comprises electrochemical, amperometric microsensors for glucose, oxygen and lactate as well as an integrated reference electrode. Microsensors have been implanted in the mouse dorsal skin fold chamber, which got inoculated with a human-pathogen bacterial strain. A selective signal could be measured for all parameters and time points. The infection led to measurable changes of the wound environment as given by a decrease of the oxygen- as well as the glucose-concentration while the lactate concentration increased markedly over time. The given results in this study are the first hints on a promising new tool and should therefore be interpreted as a proof of the principle to show the functionality of the microsensors in an in vivo setting. These microsensors could be used to monitor smoldering infections of implantable foreign materials reducing foreign implant associated complications.

Disseminated hyaline ring granuloma in the omentum of a dog

BackgroundHyaline ring granuloma (HRG) is an uncommon histopathologic finding of unsolved etiopathogenesis. According to the exogenous theory, HRG develops due to implantation of foreign material, most probably indigestible plant fragments. HRG is a comparatively rare condition in humans, mostly involving the oral cavity with very rare extraoral locations.Case presentationAn 1-year-old mixed-breed dog in good condition was presented for routine ovariohysterectomy. Disseminated HGR were accidentally found in the omental adipose tissue during surgery. Histopathology revealed the presence of ring-like hyaline structures surrounded by granulomatous inflammation including foreign body-type multinucleated giant cells. The histochemical examinations indicated the exogenous plant origin of the foreign material.ConclusionsThe lesions were similar to the findings in humans with HRG. The definitive diagnosis remains largely based on histopathological examination supported by special histochemical stains. To the best of our knowledge, this is the first case of hyaline ring granuloma reported in a non-human species. Moreover, the omentum is an uncommon location for this condition.

When the Infection Hits the Wound: Matched Case-Control Study in a Neurosurgical Patient Collective Including Systematic Literature Review and Risk Factors Analysis

To avoid surgical site infections (SSIs) by identifying patients at high risk for infectious complications, a better understanding of relevant risk factors is required. This manuscript describes a matched case-control study of patients undergoing cranial neurosurgery with postoperative surgical site infections and a systematic literature review. From January 2012 to March 2015, 70 patients (2.47%) with SSIs (out of 2819 patients) and 185 controls were identified. Statistical analyses were performed using univariate and multivariate models to identify risk factors associated with SSIs. The time of the onset of SSIs ranged from 8 to 854 days after surgery (median: 42 days). American Society of Anesthesiologists score (P= 0.003), surgical drain (P<0.001), number of previous operations (P <0.001), and implantation of foreign material (P <0.001) were significant risk factors for SSIs in multivariate analysis. In a systematic literature review, the authors identified 20 independent risk factors. This article provides information to ease the prospective assessment of patients at risk of SSI based on preoperative and postoperative risk factors. Lowering the incidence of SSIs will improve the patient outcomes and the overall quality of the healthcare delivered. To our knowledge, this is the first systemic literature review of SSIs in cranial neurosurgery and analysis of own cases in a wide spectrum.