Surgical Management of Barium Impaction: A Case Report.

Radiographic studies are used within healthcare on a routine basis to aid in the diagnosis and management of patients with a variety of health conditions. Barium sulfate is a contrast agent that may be used to enhance certain imaging studies. Although barium-contrasted studies are generally safe, they are not without risk for complications. Barium impactions, and their management, are infrequently reported in scientific literature. We present a case of a patient with barium impaction who presented at the emergency room after a fall from standing with associated symptoms of abdominal pain, weakness, and fatigue. A non-contrast computed tomography (CT) scan performed on presentation revealed the barium impaction, and initial attempts at conservative management were unsuccessful. A decompressive colonoscopy was performed without successful dissolution of the barium. Ultimately, the patient underwent exploratory laparotomy, which revealed a contained perforation of the sigmoid colon, and a successful partial colectomy with end colostomy was performed. This case study explores the surgical management of barium impaction in a comorbid patient.

Light-Emitting-Diode-Induced Fluorescence from Organic Dyes for Application in Excitation-Emission Fluorescence Spectroscopy for Food System Analysis.

An experimental study is presented on the possibility of using the fluorescence from organic dyes as a broadband light source together with a monochromator for applications in excitation-emission matrix (EEM) fluorescence spectroscopy. A high-power single-chip light-emitting diode (LED) was chosen as an excitation source with a central output wavelength at 365 nm to excite a fluorescent solution of Coumarin 1 dye dissolved in ethanol. Two excitation configurations were investigated: direct excitation from the LED and excitation through an optical-fiber-coupled LED. A Czerny-Turner monochromator with a diffraction grating was used for the spectral tuning of the fluorescence. A simple method was investigated for increasing the efficiency of the excitation as well as the fluorescence signal collection by using a diffuse reflector composed of barium sulfate (BaSO4) and polyvinyl alcohol (PVA). As research objects, extra-virgin olive oil (EVOO), Coumarin 6 dye, and Perylene, a polycyclic aromatic hydrocarbon (PAH), were used. The results showed that the light-emitting-diode-induced fluorescence was sufficient to cover the losses on the optical path to the monochromator output, where a detectable signal could be obtained. The obtained results reveal the practical possibility of applying the fluorescence from dyes as a light source for food system analysis by EEM fluorescence spectroscopy.

Structure and properties of starch - BaSO4 composite obtained using mechanical activation techniques.

The aim of this study is to obtain and characterize starch films structurally modified by in situ precipitation of BaSO4 combined with mechanical activation of casting dispersion in a rotor-stator device. By the rheological method, it was found that the modification causes a decrease in the ability of casting dispersions to structure over time. Composite films with a filler content of 0 %-15 % (w/w) were characterized using optical and SEM microscopy, FT-IR spectroscopy, and tensile and moisture resistance testing data. The maximum increase in strength (by 70 %) and elongation at break (by 870 %) is achieved with a filler content of 5 % and 15 %, respectively. An increase in the filler content to 5 % causes an increase in starch recrystallization rate, but at concentrations above 5 % of BaSO4, it inhibits retrogradation. The films obtained by mechanical activation with optimized parameters were uniformly translucent, had lower water vapor permeability than films made from starch alone, had high flexibility, and did not warp or shrink. The developed high-performance, environmentally friendly method can be recommended for the large-scale production of starch-based composite materials.

Comparison of micro-CT image enhancement after use of different vascular casting agents.

Background: Microvascular visualization is crucial in understanding the mechanisms of several pathologies. For instance, visualization of the tumor microenvironment is important in understanding angiogenesis and role in cancer progression. Visualization would provide insights to cancer diagnosis, predicting metastatic growth, and evaluating therapeutic protocols. Similarly, understanding the microvascular network could be beneficial for study of degenerative diseases and tissue repair. The use of microscale computed tomography (micro-CT) and vascular casting agents provides high-resolution images of tissue vasculature in volumetric space. The purpose of this research was to compare a selection of commercially available contrast agents to determine the optimal solution for vascular visualization. Methods: A population of 16 female nude athymic mice (Charles Rivers Laboratories) were implanted with MDA-MB-231 breast cancer cells (ATCC) orthotopically in the lower left mammary fat pad to investigate the tumor microenvironment. Once tumors reach sufficient size, animals were equally divided into four groups based on the micro-CT agent to be administered, namely, control (no contrast agent), barium sulfate (BaSO4), Vascupaint, or Microfil. Animals were anesthetized prior to transcarotid micro-cannulation to infuse 2 mL of the specific contrast agent for intravascular distribution throughout the animal. The jugular vein on the other side of the carotid artery was opened to drain blood flow. Following successful perfusion, animals and extracted organs underwent high-resolution micro-CT scanning (OI/CT, MILabs). Images were reconstructed and analyzed using analysis software to extract mean intensity signals. Results: Preliminary post-mortem micro-CT results reveal Vascupaint and BaSO4 are useful for microvascular visualization. Both Vascupaint and BaSO4 produced significant contrast-enhanced micro-CT image enhancement in the brain (3.39±0.93 and 6.27±3.78, respectively) and kidney (12.85±1.98 and 32.87±10.03, respectively) as compared to Microfil (0.22±0.07 and 0.91±0.63, respectively; P<0.05). For the various contrast agents, there were no differences in image enhancement from the liver, spleen, or tumor tissue (P>0.21). Moreover, use of Vascupaint and BaSO4 allowed for visualization of smaller microvascular structures with average diameters of 20.54±4.15 and 25.82±3.75 µm, which were smaller compared to the 91.66±24.91 µm measurements from Microfil-enhanced micro-CT images (P<0.004). Conclusions: Our study suggests that the use of Vascupaint and BaSO4 is more than sufficient for ex vivo visualization of microvascular structures with contrast-enhanced micro-CT imaging as these contrast agents more effectively perfused smaller blood vessels.

Modular air-liquid interface aerosol exposure system (MALIES) to study toxicity of nanoparticle aerosols in 3D-cultured A549 cells in vitro.

We present a novel lung aerosol exposure system named MALIES (modular air-liquid interface exposure system), which allows three-dimensional cultivation of lung epithelial cells in alveolar-like scaffolds (MatriGrids®) and exposure to nanoparticle aerosols. MALIES consists of multiple modular units for aerosol generation, and can be rapidly assembled and commissioned. The MALIES system was proven for its ability to reliably produce a dose-dependent toxicity in A549 cells using CuSO4 aerosol. Cytotoxic effects of BaSO4- and TiO2-nanoparticles were investigated using MALIES with the human lung tumor cell line A549 cultured at the air-liquid interface. Experiments with concentrations of up to 5.93 × 105 (BaSO4) and 1.49 × 106 (TiO2) particles/cm3, resulting in deposited masses of up to 26.6 and 74.0 µg/cm2 were performed using two identical aerosol exposure systems in two different laboratories. LDH, resazurin reduction and total glutathione were measured. A549 cells grown on MatriGrids® form a ZO-1- and E-Cadherin-positive epithelial barrier and produce mucin and surfactant protein. BaSO4-NP in a deposited mass of up to 26.6 µg/cm2 resulted in mild, reversible damage (~ 10% decrease in viability) to lung epithelium 24 h after exposure. TiO2-NP in a deposited mass of up to 74.0 µg/cm2 did not induce any cytotoxicity in A549 cells 24 h and 72 h after exposure, with the exception of a 1.7 fold increase in the low exposure group in laboratory 1. These results are consistent with previous studies showing no significant damage to lung epithelium by short-term treatment with low concentrations of nanoscale BaSO4 and TiO2 in in vitro experiments.

Development of Lead-Free Radiation Shielding Material Utilizing Barium Sulfate and Magnesium Oxide as Fillers in Addition Cure Liquid Silicone Rubber.

The radiological protection has the purpose of safeguarding the physical well-being of the user, preventing exposure to detrimental levels of ionizing radiation. This study introduces a novel, cost-effective category of lead-free elastomeric material designed for radiation shielding. The filler compounds utilized are notably lighter than conventional lead-based materials, enhancing user ergonomics during application. They comprise of a blend of barium sulfate combined or not with magnesium oxide with addition-cure liquid silicone rubber. To ensure the effectiveness of the radiation shielding, X-ray transmission measurements were performed for the different thicknesses of the materials and the results compared with Monte Carlo simulations. Additionally, the physical properties of the new materials, such as density, homogeneity, tensile strength, viscosity, and wettability, were also evaluated. The findings indicate that both materials fulfill the requirement for application in radiation protection garments.

Improved Optimization of a Coextrusion Die with a Complex Geometry Using the Coupling Inverse Design Method.

The main challenge in a polymer coextrusion process is to have a good die design prior to the process, which can minimize the geometric errors that are caused by extrusion swell and interface motion. For this purpose, a coupling method of optimization and inverse design for a coextrusion die was studied for a medical striped catheter. In the study, the main material was thermoplastic polyurethane (TPU), and the auxiliary material was TPU filled with 30 wt% barium sulfate. An overall optimization design method was used to optimize the geometry of the extrusion die channel for the striped catheter, which had a complex geometry. In the global optimization process, the local inverse design method was used to design the inlet of the auxiliary material. The non-linear programming by quadratic Lagrangian (NLPQL) algorithm was used to obtain the optimal geometric solution of the coextrusion die runner. The experimental verification results showed that the coupling method for coextrusion die design improved the design efficiency of the coextrusion die remarkably. The value of the objective function, which was used to measure the geometric error of the product, was reduced by 72.3% compared with the initial die design.

Performance Evaluation of Radiation-Shielding Materials and Process Technology for Manufacturing Skin Protection Cream.

Personnel using X-ray devices, the main source of radiation in medical institutions, are primarily affected by scattered rays. When interventionists use radiation for examinations/treatments, their hands may enter the radiation-generating area. The shielding gloves used for protection against these rays restrict movement and cause discomfort. Here, a shielding cream that directly adheres to the skin was developed and examined as a personal protective device; further, its shielding performance was verified. Bismuth oxide and barium sulfate were selected as shielding materials and comparatively evaluated in terms of thickness, concentration, and energy. With increasing wt% of the shielding material, the protective cream became thicker, resulting in improved protection. Furthermore, the shielding performance improved with increasing mixing temperature. Because the shielding cream is applied to the skin and has a protective effect, it must be stable on the skin and easy to remove. During manufacturing, the bubbles were removed, and the dispersion improved by 5% with increasing stirring speed. During mixing, the temperature increased as the shielding performance increased by 5% in the low-energy region. In terms of the shielding performance, bismuth oxide was superior to barium sulfate by approximately 10%. This study is expected to facilitate the mass production of cream in the future.

A Nano-Cleaning Fluid for Downhole Casing Cleaning.

In drilling and completion projects, sludge is formed as a byproduct when barite and oil are mixed, and later sticks to the casing. This phenomenon has caused a delay in drilling progress, and increased exploration and development costs. Since nano-emulsions have low interfacial surface tension, wetting, and reversal capabilities, this study used nano-emulsions with a particle size of about 14 nm to prepare a cleaning fluid system. This system enhances stability through the network structure in the fiber-reinforced system, and prepares a set of nano-cleaning fluids with adjustable density for ultra-deep wells. The effective viscosity of the nano-cleaning fluid reaches 11 mPa·s, and the system is stable for up to 8 h. In addition, this research independently developed an indoor evaluation instrument. Based on on-site parameters, the performance of the nano-cleaning fluid was evaluated from multiple angles by heating to 150 °C and pressurizing to 3.0 Mpa to simulate downhole temperature and pressure. The evaluation results show that the viscosity and shear value of the nano-cleaning fluid system is greatly affected by the fiber content, and the cleaning efficiency is greatly affected by the concentration of the nano-emulsion. Curve fitting shows that the average processing efficiency could reach 60-85% within 25 min and the cleaning efficiency has a linear relationship with time. The cleaning efficiency has a linear relationship with time, where R2 = 0.98335. The nano-cleaning fluid enables the deconstruction and carrying of the sludge attached to the well wall, which accomplishes the purpose of downhole cleaning.

Modification of Polyvinyl Chloride Composites for Radiographic Detection of Polyvinyl Chloride Retained Surgical Items.

The ever-present risk of surgical items being retained represents a real medical peril for the patient and potential liability issues for medical staff. Radiofrequency scanning technology is a very good means to substantially reduce such accidents. Radiolucent medical-grade polyvinyl chloride (PVC) used for the production of medical items is filled with radiopaque agents to enable X-ray visibility. The present study proves the suitability of bismuth oxychloride (BiOCl) and documents its advantages over the classical radiopaque agent barium sulfate (BaSO4). An addition of BiOCl exhibits excellent chemical and physical stability (no leaching, thermo-mechanical properties) and good dispersibility within the PVC matrix. As documented, using half the quantity of BiOCl compared to BaSO4 will provide a very good result. The conclusions are based on the methods of rotational rheometry, scanning electron microscopy, dynamic mechanical analysis, atomic absorption spectroscopy, and the verification of zero leaching of BiOCl out of a PVC matrix. X-ray images of the studied materials are presented, and an optimal concentration of BiOCl is evaluated.

Manipulation of Morphology, Particle Size of Barium Sulfate and the Interacting Mechanism of Methyl Glycine Diacetic Acid.

In this paper, methyl glycine diacetic acid (MGDA) was found to have great influence on the morphology and particle size of barium sulfate. The effects of additive, concentration, value of pH and reaction temperature on the morphology and particle size of barium sulfate were studied in detail. The results show that the concentration of reactant and temperature have little effect on the particle size of barium sulfate. However, the pH conditions of the solution and the dosage of MGDA can apparently affect the particle size distribution of barium sulfate. The particle size of barium sulfate particles increases and the morphology changes from polyhedral to rice-shaped with the decreasing of the dosage of MGDA. In solution with higher pH, smaller and rice-shaped barium sulfate was obtained. To investigate the interacting mechanism of MGDA, the binding energy between MGDA and barium sulfate surface was calculated. It was found that the larger absolute value of the binding energy would result in stronger growth inhibition on the crystal face. Finally, the experimental data and theoretical calculations were combined to elucidate the interacting mechanism of the additive on the morphology and particle size of barium sulfate.

Barium Sulfate Deposition in the Gastrointestinal Tract: Review of the literature.

BACKGROUND: Barium sulfate is utilized for imaging of the gastrointestinal tract and is usually not deposited within the wall of the intestine. It is thought that mucosal injury may allow barium sulfate to traverse the mucosa, and allow deposition to occur uncommonly. Most pathology textbooks describe the typical barium sulfate deposition pattern as small granular accumulation in macrophages, and do not describe the presence of larger rhomboid crystals. This review will summarize the clinical background, radiographic, gross, and microscopic features of barium sulfate deposition in the gastrointestinal tract. A review of the PubMed database was performed to identify all published cases of barium sulfate deposition in the gastrointestinal tract that have been confirmed by pathologic examination. CONCLUSIONS: A review of the literature shows that the most common barium sulfate deposition pattern in the gastrointestinal tract is finely granular deposition (30 previously described cases), and less commonly large rhomboid crystals are seen (19 cases) with or without finely granular deposition. The fine granules are typically located in macrophages, while rhomboid crystals are usually extracellular. There are various methods to support that the foreign material is indeed barium sulfate, however, only a minority of studies perform ancillary testing. Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS) can be useful for definitive confirmation. This review emphasizes the importance of recognizing both patterns of barium sulfate deposition, and the histologic differential diagnosis.

Determination of barium sulfate in barite ore by phase conversion-partial pressure-corrected headspace gas chromatography.

Barium sulfate (BaSO4) content is used to evaluate the grade of barite ore. In the present study, we report a method to determine the BaSO4 content in barite ore by phase conversion-headspace gas chromatography with partial pressure correction. In this method, the ore sample is roasted with sodium carbonate and potassium carbonate after pretreatment with hydrochloric acid. The roasted product is subsequently placed in a closed headspace bottle to react with hydrochloric acid. The ratio of CO2 to O2 signals is detected by a thermal conductivity detector for gas chromatography. Finally, the BaSO4 content in barite ore is calculated using this ratio. The method demonstrates good precision (relative standard deviation < 0.84%) and accuracy (relative error < 3.40%), with the uncertainty at 95% confidence interval at approximately +/- 0.57%. Moreover, this approach is expected to be used for the batch testing of BaSO4 content in barite ores in industrial applications.

Dendritic Mesoporous Silica Hollow Spheres for Nano-Bioreactor Application.

Mesoporous silica materials have attracted great research interest for various applications ranging from (bio)catalysis and sensing to drug delivery. It remains challenging to prepare hollow mesoporous silica nanoparticles (HMSN) with large center-radial mesopores that could provide a more efficient transport channel through the cell for guest molecules. Here, we propose a novel strategy for the preparation of HMSN with large dendritic mesopores to achieve higher enzyme loading capacity and more efficient bioreactors. The materials were prepared by combining barium sulfate nanoparticles (BaSO4 NP) as a hard template and the in situ-formed 3-aminophenol/formaldehyde resin as a porogen for directing the dendritic mesopores' formation. HMSNs with different particle sizes, shell thicknesses, and pore structures have been prepared by choosing BaSO4 NP of various sizes and adjusting the amount of tetraethyl orthosilicate added in synthesis. The obtained HMSN-1.1 possesses a high pore volume (1.07 cm3 g-1), a large average pore size (10.9 nm), and dendritic mesopores that penetrated through the shell. The advantages of HMSNs are also demonstrated for enzyme (catalase) immobilization and subsequent use of catalase-loaded HMSNs as bioreactors for catalyzing the H2O2 degradation reaction. The hollow and dendritic mesoporous shell features of HMSNs provide abundant tunnels for molecular transport and more accessible surfaces for molecular adsorption, showing great promise in developing efficient nanoreactors and drug delivery vehicles.

No inflammatory effects after acute inhalation of barium sulfate particles in human volunteers.

BACKGROUND: Most threshold limit values are based on animal experiments. Often, the question remains whether these data reflect the situation in humans. As part of a series of investigations in our exposure lab, this study investigates whether the results on the inflammatory effects of particles that have been demonstrated in animal models can be confirmed in acute inhalation studies in humans. Such studies have not been conducted so far for barium sulfate particles (BaSO4), a substance with very low solubility and without known substance-specific toxicity. Previous inhalation studies with zinc oxide (ZnO), which has a substance-specific toxicity, have shown local and systemic inflammatory respones. The design of these human ZnO inhalation studies was adopted for BaSO4 to compare the effects of particles with known inflammatory activity and supposedly inert particles. For further comparison, in vitro investigations on inflammatory processes were carried out. METHODS: Sixteen healthy volunteers were exposed to filtered air and BaSO4 particles (4.0 mg/m3) for two hours including one hour of ergometric cycling at moderate workload. Effect parameters were clinical signs, body temperature, and inflammatory markers in blood and induced sputum. In addition, particle-induced in vitro-chemotaxis of BaSO4 was investigated with regard to mode of action and differences between in vivo and in vitro effects. RESULTS: No local or systemic clinical signs were observed after acute BaSO4 inhalation and, in contrast to our previous human exposure studies with ZnO, no elevated values of biomarkers of inflammation were measured after the challenge. The in vitro chemotaxis induced by BaSO4 particles was minimal and 15-fold lower compared to ZnO. CONCLUSION: The results of this study indicate that BaSO4 as a representative of granular biopersistent particles without specific toxicity does not induce inflammatory effects in humans after acute inhalation. Moreover, the in vitro data fit in with these in vivo results. Despite the careful and complex investigations, limitations must be admitted because the number of local effect parameters were limited and chronic toxicity could not be studied.

Preparation and Biocompatibility Study of Contrast-Enhanced Hernia Mesh Material.

BACKGROUND: Meshes play a crucial role in hernia repair. However, the displacement of mesh inevitably leads to various associated complications. This process is difficult to be traced by conventional imaging means. The purpose of this study is to create a contrast-enhanced material with high-density property that can be detected by computed tomography (CT). METHODS: The contrast-enhanced monofilament was manufactured from barium sulfate nanoparticles and medical polypropylene (PP/Ba). To characterize the composite, stress tensile tests and scanning electron microscopy (SEM) was performed. Toxicity and biocompatibility of PP/Ba materials was verified by in vitro cellular assays. Meanwhile, the inflammatory response was tested by protein adsorption assay. In addition, an animal model was established to demonstrate the long-term radiographic effect of the composite material in vivo. Subsequent pathological tests confirmed its in vivo compatibility. RESULTS: The SEM revealed that the main component of the monofilament is carbon. In vitro cell experiments demonstrated that novel material does not affect cell activity and proliferation. Protein adsorption assays indicated that the contrast-enhanced material does not cause additional inflammatory responses. In addition, in vivo experiments illustrated that PP/Ba mesh can be detected by CT and has good in vivo compatibility. CONCLUSION: These results highlight the excellent biocompatibility of the contrast-enhanced material, which is suitable for human abdominal wall tissue engineering.

Onigiri esophagography as a screening test for esophageal motility disorders.

BACKGROUND/AIMS: No screening test for esophageal motility disorder (EMD) has been established, the objective of this study is to examine the potential usefulness of our newly developed "Onigiri esophagography" combined with an obstruction level (OL) classification system in screening for EMD. METHODS: A total of 102 patients with suspected EMDs who underwent both high-resolution manometry (HRM) and Onigiri esophagography between April 2017 and January 2019 were examined. The EMD diagnosis was performed based on the Chicago classification version 3.0 by HRM. Onigiri esophagography was performed using a liquid medium (barium sulfate) followed by a solid medium, which consisted of an Onigiri (a Japanese rice ball) with barium powder. The extent of medium obstruction was assessed by the OL classification, which was defined in a stepwise fashion from OL0 (no obstruction) to OL4 (severe obstruction). RESULTS: The patients with OL0 (32.3%), OL1 (50.0%), OL2 (88.0%), OL3 (100.0%), and OL4 (100.0%) were diagnosed EMDs by HRM. The area under the curve, as determined by a receiver operating characteristic analysis, for the OL classification was 0.86. Using the cutoff value of OL1, the sensitivity and specificity were 87.3% and 61.3%, respectively, while using a cutoff value of OL2, the sensitivity and specificity were 73.2% and 90.3%, respectively. CONCLUSION: In conclusion, Onigiri esophagography combined with the OL classification system can be used as a screening test for EMDs with a cutoff value of OL1.

The ability of different irrigation methods to remove mixtures of calcium hydroxide and barium sulphate from isthmuses in 3D printed transparent root canal models.

The purpose is to evaluate the efficacy of different irrigation techniques in the removal of various calcium hydroxide [Ca(OH)2] and barium sulfate [BaSO4] formulations from three isthmuses in 3-dimensional (3D) printed molar root canal models. 3D printed transparent models were designed, fabricated, and filled with pure Ca(OH)2 paste, Ca(OH)2-BaSO4 8:1 paste, Ca(OH)2-BaSO4 1:1 paste, pure BaSO4 paste, all in water, and Diapaste. Open-ended needle irrigation (ONI) at 5 and 15 mL/min, double-side-vented needle irrigation (DNI) at 5 mL/min, the GentleWave system (GW), PiezoFlow (PF), and passive ultrasonic activation (PUI) with distilled water, 0.5% sodium hypochlorite (NaOCl) and 3% NaOCl were used to remove the materials from the isthmuses. Ninety groups (n = 10) were established. The removal time was recorded from the start of irrigation to the completion of removal. GW and PF were the only methods that removed all tested materials from the isthmuses. PF required 2-3 × as much time as GW for complete removal, depending on the BaSO4 content of the paste. ONI at 15 mL/min removed pure Ca(OH)2 paste, Ca(OH)2-BaSO4 (8:1) paste, Ca(OH)2-BaSO4 (1:1) completely but could not completely remove pure BaSO4 paste and Diapaste. PUI with intermittent needle irrigation, ONI, and DNI at 5 mL/min were not able to completely remove any of the materials within 7.5 min. The GW removed all materials faster than PF, whereas other methods failed to remove all materials from the isthmuses. Pure Ca(OH)2 and the mixture with BaSO4 paste in the proportion 8:1 were removed in less time than the other mixtures by the GW, PF and ONI systems, the latter only when using 15 mL/min flow rate.

Microfluidic fabrication of imageable and resorbable polyethylene glycol microspheres for catheter embolization.

Radiopaque and degradable hydrogel microspheres have a range of potential uses in medicine including proper placement of embolic material during occlusion procedures, acting as inherently embolic materials, and serving as drug carriers that can be located after injection. Current methods for creating radiopaque microspheres are either unable to fully and homogeneously incorporate radiopaque material throughout the microspheres for optimal imaging capabilities, do not result in degradable or fully compressible microspheres, or require elaborate, time-consuming preparation. We used a simple one-step microfluidic method to fabricate imageable, degradable polyethylene glycol (PEG) microspheres of varying sizes with homogenous dispersion of barium sulfate-a biocompatible, high-radiopacity contrast agent. The imageability of the microspheres was characterized using optical microscopy and microcomputed tomography as a function of barium sulfate loading. Microspheres with 20% wt/vol barium sulfate had a mean CT attenuation value of 1,510 HU, similar to that of cortical bone, which should enable visualization with soft tissue. Compared with unloaded microspheres, barium sulfate-loaded ones saw an increase in gelation and degradation times and storage modulus and decrease in swelling. Imageable microspheres retained compressibility and were injectable via catheter. The developed radiopaque, degradable PEG microspheres have various potential uses for interventional radiologists and imaging laboratories.

Visualization of implanted mesh in the pelvic reconstructive surgery using an X-ray-detectable thread.

PURPOSE: Visualization of the implanted mesh after a pelvic floor repair surgery is important for evaluating mesh-related complications. We made an X-ray-detectable mesh and studied the histocompatibility and toxicity of it. METHODS: A thin barium sulfate thread was weaved on a traditional polypropylene mesh to make it X-ray detectable. The cytotoxicity of the mesh was tested by the MTT assay on L929 cell line. The histocompatibility and toxicity of mesh were evaluated in rabbits. Meshes were first implanted intraperitoneally. On postoperative day 7, bloods were tested to estimate the acute toxicity of meshes. After 6 months, rabbits were sacrificed and local inflammatory reaction and tissue regeneration at implantation sites were estimated by the HE stain and Masson stain. In addition, CT scans were performed after surgeries to display the location and shape of implanted meshes. RESULTS: Compared to the polypropylene mesh group, no significant difference was observed in the X-ray-detectable mesh group on both in vitro cytotoxicity and in vivo acute and chronic toxicity. The amounts of extra cellular matrix between two groups did not differ. Through CT scan and 3D remodeling, the barium sulfate thread clearly revealed the position and shape of the X-ray-detectable mesh, whereas the traditional mesh was invisible under CT scan. CONCLUSION: Adding a thin barium sulfate thread on the polypropylene mesh does not change its histocompatibility or toxicity in rabbit model. The barium sulfate thread can effectively show the location and shape of implanted mesh under CT scan.