A novel piglet model of esophageal stricture following variable segmental esophageal resection and re-anastomosis.

Background: Esophageal strictures following esophageal atresia repair are a source of significant morbidity. To test new therapeutic approaches, we designed a piglet model of esophageal stricture by resecting variable lengths of esophagus with subsequent re-anastomosis. This study describes the model and validates its physiologic impact by blinded analysis of the weight gains of the piglets.

In vitro testing of a funnel-tip catheter with different clot types to decrease clot migration in mechanical thrombectomy.

Background: Mechanical thrombectomy is the standard treatment for acute ischemic stroke in patients with large vessel occlusion and can be performed up to 24h after symptom onset. Despite high recanalization rates, embolism in new territories has been reported in 8.6% of the cases.

Multiparametric Monitoring of Early Pathophysiological Changes in a Porcine Model of Sequential Focal and Global Cerebral Ischemia.

Objective: Large animal models of cerebral ischemia have the potential to increase the translational value of stroke research. This study aims to measure early changes of brain tissue oxygen pressure (ptiO) and cerebral blood flow (CBF) to characterize a porcine model of sequential middle cerebral artery occlusion (MCAO) and common carotid artery occlusion (CCAO).

Methods: Eight juvenile German Landrace pigs received unilateral MCAO via a frontotemporal approach under continuous intraparenchymal multiparametric monitoring.

Does granulocyte-colony stimulating factor stimulate peripheral nerve regeneration? An experimental study on traumatic lesion of the sciatic nerve in rats.

Aim Of The Study: To analyse the therapeutic potential of granulocyte-colony stimulating factor (G-CSF) treatment using a rat model of traumatic sciatic nerve lesion.

Clinical Rationale For The Study: G-CSF has proven strong neurotrophic properties in various models of ischaemic and traumatic brain injury. Fewer studies exist regarding the influence of G-CSF on posttraumatic peripheral nerve regeneration.

An experimental study on long term outcomes after magnetic esophageal compression anastomosis in piglets.

Background/purpose: Previous studies have shown that a patent, watertight esophageal anastomosis can be accomplished safely using specially-shaped magnets in piglets. However, it is unclear whether such a magnetic esophageal compression anastomosis (MECA) remains patent in the long-term. The purpose of this study was to evaluate the long-term outcome of MECA in an experimental pig model over an observation period of 2 months.

Levosimendan increases brain tissue oxygen levels after cardiopulmonary resuscitation independent of cardiac function and cerebral perfusion.

Prompt reperfusion is important to rescue ischemic tissue; however, the process itself presents a key pathomechanism that contributes to a poor outcome following cardiac arrest. Experimental data have suggested the use of levosimendan to limit ischemia-reperfusion injury by improving cerebral microcirculation. However, recent studies have questioned this effect.

Implantable Sensors Based on Gold Nanoparticles for Continuous Long-Term Concentration Monitoring in the Body.

Implantable sensors continuously transmit information on vital values or biomarker concentrations in bodily fluids, enabling physicians to survey disease progression and monitor therapeutic success. However, currently available technologies still face difficulties with long-term operation and transferability to different analytes. We show the potential of a generalizable platform based on gold nanoparticles embedded in a hydrogel for long-term implanted biosensing.

Intrahematomal Ultrasound Enhances RtPA-Fibrinolysis in a Porcine Model of Intracerebral Hemorrhage.

Catheter-based ultrasound-thrombolysis has been successfully used in a small clinical trial in order to enhance recombinant tissue plasminogen activator (rtPA)-fibrinolysis, for the treatment of spontaneous intracerebral hemorrhages (ICHs). The aim of this study was to investigate the ultra-early effects of ultrasound on hematoma and the surrounding brain tissue in a porcine ICH-model. To achieve this, 21 pigs with a right frontal ICH were randomly assigned to four groups: (1) drainage ( = 3), (2) drainage + rtPA ( = 6), (3) drainage + ultrasound ( = 6), and (4) drainage + ultrasound + rtPA ( = 6).

Comparing Aachen Minipigs and Pietrain Piglets as Models of Experimental Pediatric Urology to Human Reference Data.

Introduction: Swine had special roles in the development of minimally invasive procedures to treat vesicoureteral reflux, and minipigs have been gaining ground in recent years in experimental pediatric urology as they combine small size with less vulnerable adult physiology, but their suitability as a model has never been assessed. We therefore compared a landrace piglet with a juvenile minipig to elucidate comparability.

Methods: We evaluated five 3-week old Pietrain piglets and five 3-month old Aachen Minipigs as representatives of landrace and minipig models based on their expected bodyweight being similar to a newborn human.

Comparative analysis of fibrinolytic properties of Alteplase, Tenecteplase and Urokinase in an in vitro clot model of intracerebral haemorrhage.

Objective: Hematoma lysis with recombinant tissue plasminogen activator (rtPA) has emerged as an alternative therapy for spontaneous intracerebral and intraventricular haemorrhage (ICH and IVH). However, the MISTIE III and CLEAR III trial failed to show significant improvement of favourable outcomes. Besides experimental and clinical trials revealed neurotoxic effects of rtPA.

5-Aminolevulinic Acid Multispectral Imaging for the Fluorescence-Guided Resection of Brain Tumors: A Prospective Observational Study.

Fluorescence-guided surgery with five-aminolevulinic acid (5-ALA) is the state-of-the-art treatment of high-grade gliomas. However, intraoperative visualization of 5-ALA under blue light remains challenging, especially when blood covers the surgical field and thereby fluorescence. To overcome this problem and combine the brightness of visible light with the information delivered with fluorescence, we implemented multispectral fluorescence (MFL) in a surgical microscope, a technique that is able to project both information in real-time.

A Continuous Suture Anastomosis Outperforms a Simple Interrupted Suture Anastomosis in Esophageal Elongation.

Introduction:  Long-gap esophageal atresia represents a distinct entity among the esophageal atresia spectrum. In many patients, achieving a reasonable anastomosis depends on some millimeters of tissue. We aimed to determine what effect the suturing technique would have on esophageal ex vivo elongation as it may determine the strength of a primary anastomosis.

Real-Time Overlapping of Indocyanine Green-Video Angiography With White Light Imaging for Vascular Neurosurgery: Technique, Implementation, and Clinical Experience.

Background: Fluorescent-guided techniques in vascular neurosurgery can be demonstrated via black and white indocyanine green videoangiography (ICG-VA). Multispectral imaging (MFL) is a new method, which overlaps fluorescence with the white light and provides a fluorescent white light augmented reality image to the surgeon.

Objective: To investigate (a) whether MFL can enhance the visualization of the blood-flow with simultaneous visualization of the anatomic structures and (b) if MFL can ergonomically improve the microvascular surgical treatment compared to ICG-VA.

Using multidimensional scaling in model choice for congenital oesophageal atresia: similarity analysis of human autopsy organ weights with those from a comparative assessment of Aachen Minipig and Pietrain piglets.

Swine models had been popular in paediatric oesophageal surgery in the past. Although being largely replaced by rodent models, swine experienced a revival with the establishment of minipig models. However, none of them has ever been investigated for similarity to humans.

In vitro testing of a funnel-shaped tip catheter model to decrease clot migration during mechanical thrombectomy.

One limitation of mechanical thrombectomy (MT) is clot migration during procedure. This might be caused by abruption of the trapped thrombus at the distal access catheter (DAC) tip during stent-retriever retraction due to the cylindrical shaped tip of the DAC. Aiming to solve this problem, this study evaluates the proof-of-concept of a new designed funnel-shaped tip, in an experimental in vitro setting.

Confocal-Assisted Multispectral Fluorescent Microscopy for Brain Tumor Surgery.

Optimal surgical therapy for brain tumors is the combination of complete resection with minimal invasion and damage to the adjacent normal tissue. To achieve this goal, we need advanced imaging techniques on a scale from macro- to microscopic resolution. In the last decade, the development of fluorescence-guided surgery has been the most influential breakthrough, marginally improving outcomes in brain tumor surgery.

Five-fold Gastrointestinal Electrical Stimulation With Electromyography-based Activity Analysis: Towards Multilocular Theranostic Intestinal Implants.

Background/aims: Motility disorders are common and may affect the entire gastrointestinal (GI) tract but current treatment is limited. Multilocular sensing of GI electrical activity and variable electrical stimulation (ES) is a promising option. The aim of our study is to investigate the effects of adjustable ES on poststimulatory spike activities in 5 GI segments.

An experimental study on magnetic esophageal compression anastomosis in piglets.

Introduction: Fashioning a patent, watertight anastomosis in patients with esophageal atresia is a challenging task in pediatric surgery, particularly when performed under tension. A reproducible suture-less alternative would decrease operative time. We evaluated magnetic esophageal compression anastomoses in a novel bypass-loop swine model.

Using simple interrupted suture anastomoses may impair translatability of experimental rodent oesophageal surgery.

Irreproducibility and missing translatability are major drawbacks in experimental animal studies. Hand-sewn anastomoses in oesophageal surgery are usually continuous, whereas those in experimental oesophageal surgery are widely performed using the simple interrupted technique. It has been implicated to be inferior in tolerating anastomotic tension, which we aimed to test in rats due to their importance as an animal model in oesophageal surgery.

Beyond Magnamosis: A Method to Test Sutureless Esophageal Anastomotic Devices in Living Swine by Creating an Esophageal Bypass Loop for Natural Oral Nutrition.

Thoracoscopic esophageal atresia repair has become increasingly popular, but is still limited to a few expert centers and has some challenges and shortcomings. One of them has a longer operation time compared with conventional thoracotomy. Magnetic compression anastomosis may contribute toward shorter operation times by avoiding the time-consuming anastomotic suturing.

Esophageal Biomechanics Revisited: A Tale of Tenacity, Anastomoses, and Suture Bite Lengths in Swine.

Background: Anastomotic tension has repeatedly been associated with anastomotic leakages after esophagectomy for cancer or esophageal atresia repair. We therefore aimed to determine which anastomotic technique would come as close as possible to the native esophagus in sustaining traction forces. Constant traction for several minutes at esophageal remnants and large suture bites are also considered relevant in long-gap esophageal atresia repair.

Esophageal Blood Flow May Not Be Directly Influenced by Anastomotic Tension: An Exploratory Laser Doppler Study in Swine.

Background:  Anastomotic tension has been linked to leakage and stenosis in esophageal surgery in both adults and children. We aimed to determine the effects of esophageal topography, operative technique, and anastomotic tension on esophageal blood flow.

Materials And Methods:  We divided and reanastomosed the esophagi at the carinal level with increasing levels of anastomotic tension in piglets ( = 10) and sham controls ( = 4).

Technical Aspects in Esophageal Lengthening: An Investigation of Traction Procedures and Suturing Techniques in Swine.

Introduction:  Traction procedures are useful to preserve the child's own esophagus in long-gap forms of esophageal atresia. To date, it remains unclear what suture size or position of the traction sutures is optimal to account for differences in anatomy and to reduce the risk of traction sutures being torn out of the esophageal tissue.

Materials And Methods:  Explanted porcine esophagi (from swine aged 100-120 days and weighing 100-120 kg) were divided at the carinal level.