Sheath Diameter Research Articles

First-in-human cases and preclinical experience of a novel ICE catheter.

The primary objective of our study was to evaluate the first use of a novel intracardiac echocardiography (ICE) catheter in human subjects. This study aimed to assess its practicality, image clarity, and guidance role during electrophysiology procedures. Two patients underwent procedures using the novel ICE catheter. Post-procedure evaluations were conducted by four operators, who assessed the imaging quality and overall performance of the catheter. Anatomical and blood test results were also analyzed to determine the safety and impact on internal cardiac structures. Both patients were discharged one day after the procedure without any complications. The novel ICE catheter provided comparable imaging quality to existing commercial catheters. The catheter's advanced design allowed for detailed imaging at short distances, essential for accurate diagnosis and treatment planning. Moreover, it successfully navigated complex anatomical structures like the atrial septum and left atrial appendage. These preliminary studies indicate that the novel ICE catheter achieves a level of safety and effectiveness comparable to previously available commercial catheters. The findings highlight its potential to meet current clinical needs, particularly in sophisticated anatomic interventions. Despite the prolonged thrombin time after anticoagulant administration, both types of ICE catheters were non-damaging to cardiac structures during routine operations. The study underscores the importance of using trans-septal large inner diameter sheaths to minimize complications when advancing the catheter into the left atrium.

Role of neuroimaging markers on predicting of idiopathic intracranial hypertension.

The goals of neuroimaging in idiopathic intracranial hypertension (IIH) are the exclusion of mimickers and effective management of disease. In recent studies, several imaging markers have been identified as potential predictors of IIH. To investigate the predictive roles of novel radiological markers as the Meckel's cave area, alongside classical radiologic markers in identifying IIH such as the empty sella. The patients were classified according to cerebrospinal fluid (CSF) opening pressure as the IIH group and control group. The observational, case-control study included 22 patients with IIH and 22 controls. Groups were compared for presence of empty sella, Meckel's cave area, fat area of posterior neck, fat thickness of scalp, presence of transverse sinus stenosis, and ophthalmic markers, such as increase of optic nerve (ON) sheath diameter. In the IHH group, higher occurrences of increased ON sheath diameter, ON tortuosity, flattening of the scleral surface, and transverse sinus stenosis were observed (P < 0.001, P < 0.001, P = 0.046, and P = 0.021, respectively). Meckel's cave area and fat area of posterior neck were similar in both groups (P = 0.444 and P = 0.794). Ophthalmic markers and transverse sinus stenosis could be utilized as radiologic features supporting early and precise diagnosis of IIH. However, enlargement of Meckel's cave area and measurements of fatty area of posterior neck are not helpful for diagnosis of IIH.

Automatic Optic Nerve Assessment From Transorbital Ultrasound Images: A Deep Learning-based Approach.

Transorbital Ultrasonography (TOS) is a promising imaging technology that can be used to characterize the structures of the optic nerve and the potential alterations that may occur in those structures as a result of an increase in intracranial pressure (ICP) or the presence of other disorders such as multiple sclerosis (MS) and hydrocephalus. In this paper, the primary objective is to develop a fully automated system that is capable of segmenting and calculating the diameters of structures that are associated with the optic nerve in TOS images. These structures include the optic nerve diameter sheath (ONSD) and the optic nerve diameter (OND). A fully convolutional neural network (FCN) model that has been pre-trained serves as the foundation for the segmentation method. The method that was developed was utilized to collect 464 different photographs from 110 different people, and it was accomplished with the assistance of four distinct pieces of apparatus. An examination was carried out to compare the outcomes of the automatic measurements with those of a manual operator. Both OND and ONSD have a typical inaccuracy of -0.12 0.32 mm and 0.14 0.58 mm, respectively, when compared to the operator. The Pearson correlation coefficient (PCC) for OND is 0.71, while the coefficient for ONSD is 0.64, showing that there is a positive link between the two measuring tools. A conclusion may be drawn that the technique that was developed is automatic, and the average error (AE) that was reached for the ONSD measurement is compatible with the ranges of inter-operator variability that have been discovered in the literature.

An In-Vitro Comparison of Steady State Leakage Rates through Introducer Sheaths Used for Fenestrated Endovascular Aortic Aneurysm Repair

Objectives– fEVAR involves deploying a covered stent into the aorta followed by multiple visceral stents through fenestrations in the main body of graft. The most commonly used large sheaths for cannulation of visceral vessels are the Gore DrySeal Flex, Cook Performer Check-Flo and Medtronic Sentrant. None of these sheaths were designed for the insertion of multiple sheaths, and so a slow but steady leakage of blood occurs during the procedure. The aim of this paper is to assess in an in vitro setting which large bore sheath has the best valve for use when multiple smaller sheaths are inserted through it. MethodsThree large bore introducer sheaths (LBIS) were used for this study, The Gore DrySeal Flex LBIS, Medtronic Sentrant LBIS and Cook Performer Check-Flo LBIS. A test rig was constructed, made of an 18-litre fluid reservoir mounted vertically and receiving a constant supply of water from a domestic water supply which flowed into the reservoir and out of an overflow. The reservoir was connected to the LBIS by a vertical plastic pipe with an internal diameter of 40mm and an isolation valve. The LBIS was connected to the isolation valve by inserting the LBIS up a flexible silicone tube connected to the isolation valve. The LBIS was subject to a constant column/pressure of water and fluid leakage from the LBIS was collected in a plastic pot/tray placed underneath the LBIS. The leakage rates through each LBIS were determined for the following smaller diameter sheath combinations inserted through the valve, one 6 French Sheath, two 6 French Sheaths, two 6 French Sheaths and one 7 French Sheath. This was done to closely mimic a fEVAR procedure in vitro. The procedure was to insert different sheath combinations through the non-return valves in the LBIS and measure the volume of fluid that leaked through the valves. The leaked fluid was weighed, and the weight was converted to volume using the density of water (1g/ml). ResultsThe average (mean) leakage rates for each LBIS and each sheath combination showed that leakage rates when only one sheath was inserted were very low. For all three LBIS’s tested, the leakage rates increased dramatically when multiple sheaths were inserted. The Medtronic LBIS leaked the most, followed by Cook, followed by Gore. For the Cook LBIS, the leakage rates exhibited with 2 x 6 French sheaths were approx. 106 times greater than those for the Gore LBIS and five times greater for the 2 x 6 French + 1 x 7 French sheath combination. A similar comparison for the Medtronic LBIS vs the Gore LBIS yields factors of 132 and 8. ConclusionsLeakage rates increase significantly when multiple sheaths are inserted and the Gore LBIS demonstrates significantly lower leakage than both the Cook and Medtronic during procedures that require simultaneous, multiple insertions of smaller sheaths. Although the Gore Dryseal has by far the lowest leakage rate when three small diameter sheaths are inserted (just under 1ml/s), depending on the duration of the procedure this could still result in significant blood loss.

A zero-exchange approach for left atrial access in pulmonary vein isolation with pulsed field ablation.

Pulsed field ablation (PFA) has emerged as an innovative technique for pulmonary vein isolation (PVI). Typically, a transeptal puncture (TSP) with a standard sheath precedes a switch to the larger diameter sheath in the left atrium. This study aimed to describe the safety and feasibility of direct TSP using the large diameter Faradrive sheath before performing PVI with PFA. We prospectively enrolled 166 consecutive patients with paroxysmal or persistent atrial fibrillation (AF) undergoing PVI with PFA at our institution. TSP was performed in all cases with transesophageal echocardiography guidance, using the Faradrive sheath and a 98 cm matched Brockenbrough needle. The primary endpoint was the occurrence of pericardial tamponade during or within the first 48 h after the procedure. The secondary endpoint was the occurrence of any major complication. All 166 patients were included into the final analysis (44% female): 64% of patients had paroxysmal AF and 36% persistent AF (68 ± 11 years old, median CHA2DS2Vasc Score 3, median left atrial volume index 31). The median duration of the procedure was 60 min, median time to TSP was 15 min, and the median fluoroscopy dose was 595 cGy × cm2. The primary endpoint occurred in one patient: a non-TSP related pericardial tamponade, which was managed with pericardial puncture. Direct TSP with skipping sheath exchange using the large diameter Faradrive sheath for PVI with PFA was safe, feasible, and reduced costs in all patients. Large scale studies and registries are needed to verify this workflow.

Immune-related visual dysfunction in thyroid eye disease: a combined orbital and brain neuroimaging study.

To investigate the pathological interplay between immunity and the visual processing system (VPS) in thyroid eye disease (TED). A total of 24 active patients (AP), 26 inactive patients (IP) of TED, and 27 healthy controls (HCs) were enrolled. Orbital magnetic resonance imaging (MRI) and resting-state functional MRI (rs-fMRI) were conducted for each participant. Multiple MRI parameters of the intraorbital optic nerve (ON) were assessed. The amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) were calculated. Correlation analyses were carried out on the above parameters and clinical characteristics. Visual functioning scores differentiated between the AP and IP groups. The ON subarachnoid space and ON sheath diameter were significantly higher in AP than in IP. Six vision-related brain regions were identified in TED patients compared with HCs, including right calcarine (CAL.R), right cuneus (CUN.R), left postcentral gyrus (PoCG.L), right middle temporal gyrus (MTG.R), left superior frontal gyrus (SFG.L), and left caudate (CAU.L). The brain activity of MTG.R, SFG.L, and CAU.L differentiated between the AP and IP groups. The correlation analysis revealed a close association among the vision-related brain regions, MRI parameters of ON, and clinical characteristics in AP and IP, respectively. Combined orbital and brain neuroimaging revealed abnormalities of the VPS in TED, which had a close correlation with immune statuses. Vision-related brain regions in TED might be possibly altered by peripheral immunity via a direct or indirect approach. The discovery of this study explained the disparity of visual dysfunction in TED patients with different immune statuses. With the uncovered neuroimaging markers, early detection and intervention of visual dysfunction could be achieved and potentially benefit TED patients. • Patients with different immune statuses of thyroid eye disease varied in the presentation of visual dysfunction. • The combined orbital and brain neuroimaging study identified six altered vision-related brain regions, which had a significant correlation with the MRI parameters of the intraorbital optic nerve and immunological characteristics. • Peripheral immunity might possibly give rise to alterations in the central nervous system part of the visual processing system via a direct or indirect approach.

Transradial or Transulnar Long Sheath Access to the Brachial Artery Allows for Neuroendovascular Procedures in Patients with Radial or Ulnar Artery Occlusion

Transradial access is an important tool for many neuroendovascular procedures. Occlusion of the radial or ulnar artery is not uncommon after transradial or transulnar access and can present a challenge for patients requiring repeat angiography. Between March 2022 and June 2023, patients undergoing transradial or transulnar angiography who were found to have a radial artery occlusion or ulnar artery occlusion were identified. Repeat catheterization of the occluded artery was attempted using a 21-gauge single wall puncture needle and a 0.021-inch wire to traverse the occlusion and insert a 23-cm sheath into the brachial artery. A total of 25 patients undergoing 26 angiograms during the study period were found to have a radial artery occlusion or ulnar artery occlusion. Successful repeat catheterization of the occluded artery was achieved in 21 of 26 cases (80.7%). Outer diameter sheath size ranged from 5 Fr (0.0655 inch) to 8 Fr (0.1048 inch). No access complications were encountered. Number of prior angiograms, time since prior angiogram, and prior angiogram procedure time were associated with lower likelihood of successful access. Transradial or transulnar neuroangiography through an occluded radial or ulnar artery is safe and feasible by traversing the occlusion into the brachial artery with a 23-cm sheath. Repeat catheterization is most successful in patients with an arterial occlusion <6 months old. This technique is important in patients who have limited options for arterial access, avoiding access site complications inherent in transfemoral access, and in patients who specifically require radial or ulnar artery access.

Prognostic value of extraocular muscles for intraocular pressure in thyroid-associated ophthalmopathy patients.

Persistent increase in intraocular pressure (IOP) is often observed in eyes with thyroid-associated ophthalmopathy (TAO), which has irreversible effects on the visual function of patients. This retrospective cross-sectional study evaluated the value of magnetic resonance imaging (MRI) measurements of extraocular muscle (EOM) volume in prognosing IOP in patients with TAO. This single-center study was conducted in Beijing Friendship Hospital (Beijing, China), a tertiary hospital. From 35 participants, 70 eyes (normal IOP group: 50 eyes; high IOP group: 20 eyes; random samples) were enrolled in this study. Basic data from patients were collected and compared using 2-sample t-tests and chi-squared tests. The volume of the EOM, orbit fat, and whole orbit were measured by orbital MRI. Moreover, proptosis, optic nerve (ON) sheath diameter, optic nerve angle (ONA), and gaze angle were additionally measured with MRI. These parameters were compared between the two groups using 2-sample t-tests and chi-squared tests. Before and after post-methylprednisolone therapy, the MRI data of 20 eyes were obtained and compared with a paired t-test. Peripapillary retinal nerve fiber layer (RNFL) thickness was obtained using an optical coherence tomography (OCT) scan. Spearman rank correlation analysis, logistic regression analysis, and receiver operating characteristic (ROC) curves were performed to evaluate the role of these factors in IOP changes. The EOM volume and axial and sagittal ONAs in the high-IOP group were significantly increased compared to the normal-IOP group (P<0.001, P=0.001, P=0.02, respectively). Logistic regression analysis indicate that the cutoff value for EOM volume for the diagnosis of high IOP was significantly larger than that of the other parameters except orbit volume (P=0.03, P=0.004, P=0.08, respectively). Spearman correlation analysis revealed a significant correlation between EOM volume and ON sheath diameter and average RNFL thickness (P=0.01, P=0.02, respectively). A paired t-test indicated a significant decrease of EOM volume and ON sheath diameter as well as a significant enlargement of the axial ONAs after methylprednisolone therapy (P=0.002, P=0.02, P=0.05, respectively). EOM volume was an effective diagnostic factor for tracking IOP changes and ON patterns in patients with TAO. Methylprednisolone therapy is recommended for patients with TAO with secondary glaucoma to quickly reduce the EOM volume.

A simple carbon fiber heating wire design method for preventing ice accretion on stay cables

In cold weather, the outer surface of stay cable sheaths easily freezes. When the ambient temperature increases, the ice on the surface melts easily, and there is a risk of falling ice at high altitudes. In this paper, a simple design method is proposed that uses carbon fiber heating wires to prevent the icing of stay cables. Conventional indoor tests and numerical simulations of heat conduction are carried out for a sheath with a single diameter, and the number of heating wires required for different diameter sheaths is obtained. Taking the stay cable sheath of the Qingshan Bridge in Wuhan as an example, when the diameters of the heating wire and the stay cable sheath are 6 mm and 200 mm, respectively, the temperature rise rule of the heating wire, the calibrated heating power and the convective coefficients are obtained through tests and numerical simulations. At an ambient temperature of 4 °C, thread-like ice formed in the arc range of 0.314 m on the surface of the sheath. The critical non-icing temperature required by the heating wire during preheating to ensure that the sheath surface does not freeze is 1.5 °C.

Assessment of collection samples of leeks for cultivation and breeding in the North-Western region of the Russian Federation

21 collection samples of leek were assessed to identify appreciable varieties for breeding and cultivation in the conditions of the North-Western region of Russia. The study was performed in 2015-2019 at the experimental field of the Pushkin laboratories of the Department of Genetic Resources of Vegetable Crops of N.I. Vavilov Institute of Plant Genetic Resources. We have found varietal differentiation in terms of growth, yield and biochemistry of the studied leek samples. The dynamics of leek growth identified an advantage in the number of leaves, the sheath diameter and the increase in plant mass in the Anika, Lincoln and Banditd samples in 2015-2016 and in the Gayia, Elefant and Malabare samples in 2018-2019, which provided a heavy yield.

Safety and Ease of Sheath Insertion During Endovascular Treatment Via the Common Femoral Artery After Endarterectomy With Autologous Repair: A Retrospective Cohort Study.

Background Endovascular treatment (EVT) using the common femoral artery (CFA) for access after endarterectomy (EA) may result in sheath insertion difficulties because of subcutaneous scar tissue, as well as difficulties with hemostasis. We evaluated the safety of CFA access and the ease of sheath insertion over time after EA. Method We included 19 patients (21 limbs, 40 cases) in whom the CFA was used after EA with autologous repair as an access route in EVT for peripheral arterial disease in our institution from January 2013 to December 2020. Nine limbs underwent simple closure repair and 12 underwent autologous patch repair. Difficult sheath insertions were defined as those in which additional devices (stiff guidewire or a smaller diameter sheath for dilation) were used for scheduled sheath insertion. The inability to insert a sheath with the scheduled diameter was defined as a failed sheath insertion. We evaluated the EVT timing after EA for difficult sheath insertions, and whether the CFA was repaired with simple closure or autologous patch repair during EA surgery. Results There were 10 (25%) difficult sheath insertions, with one (2.5%) failure. The rate of difficult sheath insertions peaked from 6 months to 1 year after EA and gradually decreased (47% from 6 months to 3 years, 14% thereafter). There were more statistically significant difficult sheath insertions with simple closure repair (50%) than with autologous patch repair (12%) (P = 0.018). Hemostasis devices were used in 90% of EVT cases. The median maximum sheath diameter was 6 Fr (mean = 5.8 Fr). None of the cases required surgical procedures to achieve hemostasis after EVT. Conclusion EVT may be performed safely using the CFA after EA. The difficulty of sheath insertion may differ depending on the EVT timing after EA; it was more difficult with simple closure than with autologous patch repair, possibly related to scar formation.

Abstract 1122‐000081: Initial Experience Implementing the Transradial Approach for Diagnostic Cerebral Angiography

Introduction : The transradial approach (TRA) has gained acceptance among interventionists due to the lower operative complication rates, less operative time and better patient comfort. Our study aimed to analyze our experience in the implementation of the TRA for diagnostic cerebral angiographies. Methods : Between March 2020 and July 2021, consecutive patients who underwent TRA in two institutions were selected and data was retrospectively collected. Demographics, technical details of the procedure, duration of the procedure, fluoroscopy time and radiation exposure were analyzed. Results : A total of 76 angiographies using the TRA were done. The mean age was 47.5 ± 16.8 years (8 – 82 years). Women represented 57% of cases. Successful radial artery (RA) catheterization was done in 94% (85 patients/80 successful). A preoperative cocktail was used in all the cases. Subcutaneous lidocaine and a 5F sheath were used in 46% and 57% of cases, respectively. The Simmons 2 catheter was used in all the cases. Glidecath, followed by Merit were used in 40% and 32% of the cases, respectively. Right internal carotid artery (ICA), left ICA, right vertebral artery (VA), left VA, right external carotid artery (ECA) and left ECA were studied in 95%, 91%, 76%, 20%, 20% and 15% of the cases, respectively. Post‐operative vasospasm occurred in 29% of the cases, which resolved with intra‐arterial verapamil. Vasospasm was not associated with sheath diameter (p = 0.129) or local anesthesia (p = 0.065). The mean fluoroscopy time was 16 minutes. Conversion to TFA was done in 9 patients (10.6%), of which the RA was successfully catheterized in 4 patients: 1 patient had an atheroma in the brachial artery, 1 patient had a thrombus in the subclavian artery and 2 patients presented severe pain in the forearm. In the remaining 5 patients, there were 2 radial dissections and in 3 the RA could not be approached. Conclusions : The TRA is a safe and effective alternative to perform diagnostic cerebral angiographies with conversion rates according to the literature. The use of appropriate catheters is necessary in order to lower fluoroscopy times when this technique is chosen.

Evaluation of Increased Intracranial Pressure with the Optic Nerve Sheath Diameter by Ultrasound in Epiduroscopic Neural Laser Discectomy Procedures

In order to clarify the camera image and open the adhesions mechanically during epiduroscopy, saline is injected continuously in the epidural area. As a result, an increase in intracranial pressure is to be expected in theory. Increased intracranial pressure can be evaluated by measuring by optic nerve sheath diameter. This study was designed to evaluate the relationship between optic nerve sheath diameter measurements and intracranial pressure, after injecting fluid to the epidural area during epiduroscopy procedures performed in our clinic. Retrospective study. Sakarya University Training and Research Hospital. During the epiduroscopy procedure, pre and postoperative bilateral optic nerve sheath diameters were measured with an ultrasonography probe. With the patients' eyelids closed, the probe was placed on the orbita in the sagittal plane, measuring 3 mm posterior of the papilla. While there was a statistically significant difference between pre- and post-operative optic nerve sheath diameter measurements, there was no significant correlation with processing time, amount of fluid delivered, or fluid delivery rates. One of the limitations of this study is the retrospective collection of data. A second limitation is that repetitive measurements were not performed, instead of a single postoperative measurement. We think more prospective randomized controlled studies are required to examine the increase in the diameter of the optic nerve sheath, which is an indirect indicator of increased intracranial pressure after epiduroscopy applications, in order to determine whether the pressure increase is associated with the rate of fluid delivery, the total fluid amount, or the processing time.

Cerebrospinal fluid dynamics along the optic nerve in patients with spontaneous cerebrospinal fluid rhinorrhea: a retrospective computed tomographic cisternography study.

Spontaneous cerebrospinal fluid (CSF) rhinorrhea is related to intracranial pressure (ICP) and dynamic changes. This study investigated CSF dynamics along the optic nerve (ON) in patients with spontaneous CSF rhinorrhea. The computed tomographic (CT) cisternographies of 66 patients (132 eyes) with spontaneous CSF rhinorrhea were analysed. The contrast-loaded CSF (CLCSF) density was measured in Hounsfield units (HU) at three regions of interest (ROIs) along the ON and adjusted by the basal cistern density. The CLCSF density and ON sheath diameter (ONSD) were analysed between both sides in the different ICP groups. When comparing the density of CLCSF along the ON, no significant differences were found between the ipsilateral and contralateral sides of the leakage. The distribution of CLCSF along the ON showed a highly significant density reduction from the canalicular segment to the bulbar segment on both sides. The CLCSF density significantly decreased on the ipsilateral ON in the canalicular segment and tended to decrease on the ipsilateral ON in thebulbar and canal segments compared with that on the contralateral ON in the low-ICP group. The ONSD tended to decrease on the ipsilateral side of leakage. According to the CLCSF density on CT cisternography, CSF dynamics along the ON may bilaterally decrease from the optic canal to the retrobulbar segment. Cerebrospinal fluid (CSF) dynamics are possibly influenced by differences in ICP, and a lower ICP may cause more obvious differences or impairments in CSF dynamics along the ipsilateral ON.

Experimental Study on Tensile Properties of Sugarcane Leaves

Highlights This article focuses on the tensile properties of sugarcane leaves. The moisture content and sheath diameter were selected as test factors, and the test index was the stalk-leaf connecting force. The load-displacement curves of stalks and leaves were plotted. Two-way ANOVA was also discussed. Abstract . The tensile properties of sugarcane leaves are critical factors affecting the harvesting quality of sugarcane harvesters. Thus, it is important to investigate the tensile properties of sugarcane stalks and leaves. The selected test factors were leaf moisture content and sheath diameter, and the stalk-leaf connecting force was selected as test index. The tests were conducted with two moisture content levels of 15% and 20%, and three sheath diameters of 22, 26, and 30 mm. The stress-strain curves of stalks and leaves were plotted to show how the tensile force varied during the tensile test. The results showed that there was a strong linear correlation between the stalk-leaf connecting force and diameter of leaf sheath, and the connecting force also increased with the increasing moisture content. In addition, leaf tensile forces in longitudinal direction were much larger than in transverse direction. Two-way ANOVA revealed that both of the moisture contents (A) and sheath diameters (B) had significant effects on the stalk-leaf connecting force (p &amp;lt; 0.01), however, the interaction between A and B was not significant (p &amp;gt; 0.1). This study provides a theoretical reference for the design and improvement of crop dividers of sugarcane harvester. Keywords: Moisture content, Sheath diameter, Stalk-leaf connecting force, Sugarcane leaves, Universal testing machine, Tensile properties.

The "no-touch" technique in the flexible ureteroscopic approach of renal stones.

Large meta-analyses demonstrated that ureteral access sheaths (UAS) have specific complications during and after flexible ureteroscopy (fURS). The present study focused on the technical aspects, advantages, drawbacks, and limitations of the latest “no-touch” technique (NTT) in the flexible ureteroscopic therapeutic approach of renal stones. A total of 288 patients with a single pyelocaliceal stone (largest diameter between 11 and 29 mm) underwent fURS: 144 using the 12/14 Fr UAS (group 1) and 144 without UAS (group 2). For NTT, we used four types of ureteroscopes: Olympus URF-V2 (8.5 Fr) – 33 cases, Storz Flex X2 (8.4 Fr) – 60 cases, single-use PUSEN PU 3022 (9.5 Fr) – 37 cases, and single-use PUSEN – PU 3033A (7.5 Fr) – 14 cases. For group 1, we used the Olympus URF–V2 ureteroscope in 44 cases, the Storz Flex X2 in 58 cases, and the single-use PUSEN PU 3022 in 42 cases. We compared the operative time, hospitalization periods, and complications. Successful access sheath insertion was noted in 83.3% of cases from group 1, and successful ureteroscope insertion was noted in 90.9% of cases from group 2. The average operative time was slightly higher in group 1 vs. group 2 (47 vs. 39 min). Stone-free rates (SFRs) were overall lower in group 2 (76.3% vs. 86.8%) at 1 month. At 3 months, we did not find a significant difference between these two groups. Superficial mucosal ureteral wall lesions were found in 38.8% of patients from group 1 and 4.1% from group 2. Hospitalization periods were longer in group 1 vs. group 2 (21 vs. 29 hours, respectively). The single-use 7.5 Fr ureteroscope should receive a special mention: the insertion was simple, we did not encounter any mucosal ureteral wall lesions, and all patients were discharged on the same day. Despite the clear advantages of routine UAS usage, there are many adverse events for the patient. Larger diameter sheaths involve a greater risk of ureteral wall injury. NTT seems to improve peri- and postoperative safety while preserving therapeutic efficiency. The new 7.5 Fr ureteroscopes appear to optimize surgical efficiency and diminish complications in the flexible ureteroscopic treatment of renal stones.

Morphological Changes in the Tibial Nerve During the Treatment of Large Tibia Defects Using Ilizarov Apparatus Combining with the Masquelet Technique: Experimental Study

Background. The use of Masquelet technology in combination with non-free osteoplasty according to Ilizarov in order to compensate large defects of the lower leg bones provides proper bone union and recurrence-free course of the disease, but the problem of patient rehabilitation remains relevant. The course and duration of the recovery period depend on the morphofunctional state of the tibial nerves. The purpose of this study was to determine morphological changes in the tibia nerve of dogs during the experimental treatment of large tibial defects using Ilizarov apparatus combining with the Masquelet technique. Materials and Methods. A defect of the upper third of the tibia in the form of false joint was created in 10 mongrel dogs. Then this defect was replaced with 25 mm diastasis, into which a cement spacer was placed. After 30 days, the latter was removed. At the level of the lower third, transverse osteotomy was performed, as well as distraction of 1 mm rate for 4 times per day, until complete contact of the fragments in the defect zone. The tibial nerves were studied within the periods of 60 days of fixation (F60) and 30 days after the fixator removal (FR30). Results. There were no mechanical damages of the nerves. During the experiment a part of epineural veins and arteries had obliterated lumens, two-fold decrease in the numerical density of endoneural arterioles, venules and capillaries was observed in FR30 — 97.5±2.5 in 1 mm2 (normally — 182.0±22.0), that evidenced of microcirculatory disorders progressing towards the end of the experiment. Patterns of Wallerian degeneration were found along with typical damages to fibers during distraction osteosynthesis demyelination and axonal degeneration. In F60 the proportion of modified fibers was 7.7±1.5%, which was 4.8 times higher (р = 0.52×10-5) above normal, the numerical densities and dimensional characteristics of fibers decreased. At the end of the experiment, the proportion of modified conductors 2.3-fold exceeded the norm (p = 0.33×10-4) — 3.7±0.4%, the numerical density of fibers remained 10.2% below the norm (p = 0.0362), making up 17436±865, but the average axon diameter and thickness of myelin sheaths were restored. Conclusion. Microcirculatory dysfunction, axonal atrophy, demyelination, Wallerian degeneration of a part of myelin nerve fibers and a decrease in their number revealed in the tibial nerves during the treatment of large tibia defects using the Masquelet technique combining with Ilizarov non-free bone grafting indicated the need for the use of adequate neurometabolic pharmacotherapy and effective rehabilitation.

Effect of β-mannanase enzyme supplementation on the morphofunctional state of broiler chickens’ immunocompetent organs

Identifying and eliminating factors that interfere with the nutrient absorption from feed is essential for successful poultry rearing. The nutritional value of feed mixtures used in the poultry industry can be increased by the use of enzyme supplements, in particular β-mannanase (Hemicell), which breaks down the anti-nutrients β-mannans that are present in significant quantities in soy products. For the study, two groups of 50 broiler chickens were formed. In the control group a standard feed mixture from cereals was used, particularly soybeans, and in the experimental group 0.05% β-mannanase enzyme supplement (Hemicell) in addition to the compound feed was used. Production indicators were established (average daily gain, survival rate, feed costs). On the 15th, 25th and 42nd days of rearing, lymphatic organs (cloacal bursa and spleen) were collected from seven chickens of each group, followed by macro, microscopic and morphometric evaluation. It was found that the addition of an enzyme supplement promotes an increase in the production indicators of poultry rearing, reduces feed use, does not affect the macroscopic characteristics of the lymphatic organs. β-mannanase (Hemicell) contributes to the maintenance of an active morphofunctional state of the cloacal bursa and spleen during the entire period of poultry rearing. This was manifested by high indices of the absolute and relative organ masses, a moderate development degree of tissue components and cloacal bursa histological structures (number, shape and average length of lymphatic nodules, density of lymphocytes in the cortex and medulla) and spleen (number and diameter of lymphatic nodules and periarterioal lymphatic sheaths). In the control group, at all stages of rearing, the morphofunctional state of the bursa was found to be lower and signs of immunosuppression were revealed by the end of the rearing period (a sharp decline in the bursa absolute mass, organ mass index, a decrease in the average length of nodules, change in their shape, thinned cortical layer and delymphotisation). The morphofunctional state of the spleen of chickens from the control group remained high throughout the entire study period. So use of the β-mannanase enzyme supplement (Hemicell) while rearing broiler chickens not only increased the efficiency of their rearing but also contributed to maintaining a high morphological and functional state of the cloacal bursa.

Response times of meteorological air temperature sensors

AbstractGuidelines in the Guide to Meteorological Instruments and Methods of Observation (the CIMO guide) of the World Meteorological Organization (WMO, published 2014, updated 2017, section 2.1.3.3, Response times of thermometers) recommend that the 63% response time τ for an air temperature sensor be 20 s, although – as airflow speed influences response time – the minimum airflow speed at which this applies should also be specified in the document. A 63% response time τ63 = 20 s implies that 95% of a step change be registered within 3τ63 or 60 s, the WMO recommended averaging interval for air temperature: rapid air temperature changes on this time‐scale are not uncommon, often associated with convective squalls, frontal systems or sea breeze circulations. An alternative way of expressing the effect of the time constant is that in air whose temperature is changing at 0.1 K·min−1 the thermometer would lag by approximately 0.03 K.To assess whether this response time specification was realistic, we have undertaken an experimental and theoretical study of the time constants of meteorological thermometers. Laboratory wind tunnel tests were undertaken to quantify 63% and 95% response times of 25 commercial 100 Ω platinum resistance thermometers (PRTs) of various sizes (length and sheath diameter) from five manufacturers. The test results revealed a fourfold difference in response times between different sensors: none of the PRTs tested met the CIMO response time guideline at a ventilation speed of 1 m·s−1 assumed typical of passively ventilated thermometer shields such as Stevenson‐type thermometer screens. A theoretical model of the sensors was devised which matched the experimental behaviour with regard to the most important contributing factors, namely ventilation rate and sensor diameter. Finally, suggestions and recommendations for operational air temperature sensor adoption and future sensor development are included.

Ultrasound-guided thrombin injection for treatment of iatrogenic femoral artery pseudoaneurysms compared with open surgery: first experiences from a single institution.

PurposeThe frequency of iatrogenic femoral artery pseudoaneurysm (FAP) diagnoses has recently increased due to the growing use of diagnostic and interventional procedures involving large diameter sheaths, as well as more potent anticoagulation procedures. In this study, we aimed to present our experience with ultrasound-guided thrombin injection (UGTI) in patients with iatrogenic FAP.MethodsWe studied patients with FAP who were under anticoagulant or antiplatelet therapies preoperatively, or who had received a loading dose during an interventional procedure. The outcomes of patients with FAP treated with UGTI were compared with those of patients who underwent open surgical repair for pseudoaneurysms.ResultsAmong the 55 patients included in this study, 24 had UGTI while 31 had open surgery. The success rate was 95.8% when taking into consideration primary and secondary attempts. The mean duration of the procedure was shorter in patients with UGTI (10.1 ± 3.54 minutes) when compared with those who underwent open surgery (76.55 ± 26.74 minutes, P ≤ 0.001). In addition, the total complication frequency was significantly higher in the open surgery group (P = 0.005), as was their length of hospital stay (P < 0.001). Cost analysis showed significant differences between UGTI ($227.50 ± $82.90) and open surgery ($471.20 ± $437.60, P = 0.01).ConclusionWe have found that UGTI is the safer and more effective choice of treatment in appropriate patients with FAP, as opposed to surgery.