Asunto(s)

RESUMEN

Catheter-based embolization has become a widely adopted minimally-invasive treatment for a broad range of applications. However, assessment of embolization endpoints requires x-ray fluoroscopic monitoring, exposing patients and physicians performing embolization procedures to harmful ionizing radiation. Moreover, x-ray fluoroscopy assessment of embolization endpoints is low sensitivity, subjective, and may not reflect the actual physiology of blood flow reduction, thus providing little oversight of the embolization procedure. Inspired by the observation that the dielectric properties of blood differ from those of fluids injected during the embolization procedure, a customized angiographic catheter was created with embedded electrodes for catheter-based electrochemical impedance spectroscopy as a way to monitor embolization. Real-time electrochemical impedance spectroscopy was performed in a phantom and compared to visual and videographic monitoring. Electrochemical impedance spectroscopy was able to sense endpoints of embolization, including stasis, reflux, and persistent flow. This new technique offers a label-free method of sensing embolization progress with potentially higher sensitivity and reproducibility compared to x-ray, as well as offer substantial reduction in x-ray exposure to patients and physicians.

Asunto(s)

RESUMEN

Intracranial aneurysm is the primary cause of nontraumatic subarachnoid hemorrhage. To assess aneurysm metabolism, we present a method of intra-operatively collecting blood samples from the aneurysm neck, as well as the proximal and distal responsible vessels, using microcatheters. Through these paired comparisons, we can eliminate the interpatient variation usually observed in plasma samples taken from the peripheral vein. We utilized 39 plasma samples from 13 intracranial patients to characterize the metabolite profiles using untargeted liquid chromatography-mass spectrometry. Our findings revealed that L-tyrosine is upregulated at relatively high levels at the aneurysm neck than the proximal and distal aneurysm, whereas phenylpyruvic acid, L-cystine, and L-ornithine are downregulated. Based on this, there was also a significant decrease in arginine within small aneurysm of the internal carotid artery. The 6-month follow-up indicated that patients who experienced good recovery had lower levels of biliverdin, bilirubin, and metabolites of coenzyme Q within the aneurysm. In conclusion, our investigation provides a comprehensive overview of plasma metabolites in patients with intracranial aneurysms, shedding light on potential pathogenetic mechanisms in unruptured intracranial aneurysms. Moreover, the study proposes innovative ideas for establishing postoperative follow-up timelines for flow diverter devices.

Asunto(s)

RESUMEN

Catheter-related infections are one of the most common nosocomial infections with increasing morbidity and mortality, and robust antibacterial or antifouling catheter coatings remain great challenges for long-term implantation. Herein, multifunctional hydrogel coatings were developed to provide persistent and self-adaptive antifouling and antibacterial effects with self-healing and lubricant capabilities. Polyvinyl alcohol (PVA) with ß-cyclodextrin (ß-CD) grafts (PVA-Cd) and 4-arm polyethylene glycol (PEG) with adamantane and quaternary ammonium compound (QAC) terminals (QA-PEG-Ad) were crosslinked through host-guest recognitions between adamantane and ß-CD moieties to acquire PVEQ coatings. In response to bacterial infections, QACs exhibit reversible transformation between zwitterions (pH 7.4) and cationic lactones (pH 5.5) to generate on-demand bactericidal effect. Highly hydrophilic PEG/PVA backbones and zwitterionic QACs build a lubricate surface and decrease the friction coefficient 10 times compared with that of bare catheters. The antifouling hydrated layer significantly inhibits blood protein adsorption and platelet activation and reveals negligible hemolysis and cytotoxicity. The dynamic host-guest crosslinking achieves full self-healing of cracks in PVEQ hydrogels, and the mechanical profiles were recovered to over 90 % after rejuvenating the broken hydrogels, exhibiting a long-term stability after mechanical stretching, twisting, knotting and compression. After subcutaneous implantation and local bacterial infection, the retrieved PVEQ-coated catheters display no tissue adhesion and 3 log folds lower bacterial number than that of bare catheters. PVEQ coatings effectively prevent the repeated bacterial infections and there are few inflammatory reactions in the surrounding tissue, while substantial lymphoid infiltration and inflammatory cell aggregation occur in muscle tissues around the bare catheter. Thus, this study demonstrates a catheter coating strategy by on-demand bactericidal, self-adaptive antifouling, self-healing and lubricant hydrogels to address medical devices-related infections. STATEMENT OF SIGNIFICANCE: It is estimated over two billion peripheral intravenous catheters are annually used in hospitals around the world, and catheter-associated infection has become a great clinical challenge with rapidly rising morbidity and mortality. Surface coating is considered a promising approach, but substantial challenges remain in the development of coatings that simultaneously satisfy both anti-fouling and antibacterial attributes. Even more, few attempts have been made to design mechanically robust coatings and reversible antibacterial or antifouling capabilities, which are critical for long-term medical implants. To address these challenges, we propose a concise strategy to develop hydrogel coatings from commercially available poly(ethylene glycol) and polyvinyl alcohol. In addition to self-healing and lubricant capabilities, the reversible conversion between zwitterionic and cationic lactones of quaternary ammonium compounds enables on-demand bactericidal and self-adaptive antifouling effects.

Asunto(s)

RESUMEN

BACKGROUND: To prospectively evaluate the technical efficacy and safety of the double-lumen eustachian tube (ET) balloon catheter in patients with ET dysfunction. METHODS: Patients who were diagnosed with ET dysfunction and needed balloon eustachian tuboplasty (BET) were prospectively enrolled. A double-lumen ET balloon catheter was used to dilate the ET and inject medicine. Efficacy results were assessed by the injection channel patency (ICP) rate, the injection reached the expected site (IRES) rate, and the improvement in eustachian tube function was evaluated by the seven-item Eustachian Tube Dysfunction Questionnaire (ETDQ-7) score. Safety results were assessed in terms of adverse events and device defects. RESULTS: BET was successfully attempted in 87 patients from April 2022 to August 2022 at two academic medical centers in China (01, 02). The ICP rate was 100%, and the IRES rate was 88.51%. The overall ETDQ-7 score was significantly reduced ( p < 0.001) postsurgically at both centers. There were no major complications or device defects. CONCLUSION: The double-lumen ET balloon catheter is technically effective and safe for the treatment of ET dysfunction.

Asunto(s)

RESUMEN

Electromagnetic tracking of endovascular instruments has the potential to substantially decrease radiation exposure of patients and personnel. In this study, we evaluated the in vivo accuracy of a vessel-based method to register preoperative computed tomography angiography (CTA) images to physical coordinates using an electromagnetically tracked guidewire. Centerlines of the aortoiliac arteries were extracted from preoperative CTA acquired from five swine. Intravascular positions were obtained from an electromagnetically tracked guidewire. An iterative-closest-point algorithm registered the position data to the preoperative image centerlines. To evaluate the registration accuracy, a guidewire was placed inside the superior mesenteric, left and right renal arteries under fluoroscopic guidance. Position data was acquired with electromagnetic tracking as the guidewire was pulled into the aorta. The resulting measured positions were compared to the corresponding ostia manually identified in the CTA images after applying the registration. The three-dimensional (3D) Euclidean distances were calculated between each corresponding ostial point, and the root mean square (RMS) was calculated for each registration. The median 3D RMS for all registrations was 4.82 mm, with an interquartile range of 3.53-6.14 mm. A vessel-based registration of CTA images to vascular anatomy is possible with acceptable accuracy and encourages further clinical testing. RELEVANCE STATEMENT: This study shows that the centerline algorithm can be used to register preoperative CTA images to vascular anatomy, with the potential to further reduce ionizing radiation exposure during vascular procedures. KEY POINTS: Preoperative images can be used to guide the procedure without ionizing intraoperative imaging. Preoperative imaging can be the only imaging modality used for guidance of vascular procedures. No need to use external fiducial markers to register/match images and spatial anatomy. Acceptable accuracy can be achieved for navigation in a preclinical setting.

Asunto(s)

RESUMEN

PURPOSE: This study aimed to develop an algorithm for the automatic detecting chest percutaneous catheter drainage (PCD) and evaluating catheter positions on chest radiographs using deep learning. METHODS: This retrospective study included 1,217 chest radiographs (proper positioned: 937; malpositioned: 280) from a total of 960 patients underwent chest PCD from October 2017 to February 2023. The tip location of the chest PCD was annotated using bounding boxes and classified as proper positioned and malpositioned. The radiographs were randomly allocated into the training, validation sets (total: 1,094 radiographs; proper positioned: 853 radiographs; malpositioned: 241 radiographs), and test datasets (total: 123 radiographs; proper positioned: 84 radiographs; malpositioned: 39 radiographs). The selected AI model was used to detect the catheter tip of chest PCD and evaluate the catheter's position using the test dataset to distinguish between properly positioned and malpositioned cases. Its performance in detecting the catheter and assessing its position on chest radiographs was evaluated by per radiographs and per instances. The association between the position and function of the catheter during chest PCD was evaluated. RESULTS: In per chest radiographs, the selected model's accuracy was 0.88. The sensitivity and specificity were 0.86 and 0.92, respectively. In per instance, the selected model's the mean Average Precision 50 (mAP50) was 0.86. The precision and recall were 0.90 and 0.79 respectively. Regarding the association between the position and function of the catheter during chest PCD, its sensitivity and specificity were 0.93 and 0.95, respectively. CONCLUSION: The artificial intelligence model for the automatic detection and evaluation of catheter position during chest PCD on chest radiographs demonstrated acceptable diagnostic performance and could assist radiologists and clinicians in the early detection of catheter malposition and malfunction during chest percutaneous catheter drainage.

Asunto(s)

Asunto(s)

RESUMEN

BACKGROUND: Double lumen balloon catheters (DLBCs) have emerged as a potential alternative to single lumen balloon catheters for endovascular embolization of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (dAVFs). This study describes our preliminary experience with the Eclipse 2L DLBC in treating AVMs and dAVFs. METHODS: Patients who underwent embolization of cranial dAVFs or AVMs at our institution from August 2021 to March 2024 were included. Spinal vascular malformations were excluded. Descriptive statistics were used to analyze procedural outcomes, technical nuances, and postoperative outcomes on follow-up. RESULTS: Twenty-five patients who underwent 38 embolization procedures (15 AVMs and 23 dAVFs) met criteria for inclusion in this study. The mean age of the cohort was 52.44 (standard deviation = 17.26), and 48% of the overall cohort (n = 13) was female. The average procedure times for AVMs and dAVFs were 80.4 minutes and 96.73 minutes, respectively. There was 1 instance of catheter entrapment. Two patients in the AVM cohort experienced mortality, and 1 experienced postoperative rupture. CONCLUSIONS: Our preliminary experience using the Eclipse 2L balloon catheter for Onyx embolization reported procedural outcomes comparable to other DLBCs despite relatively higher procedure times and radiation doses. Further long-term studies on its efficacy as primary modality in treating AVMs and dAVFs are encouraged.

Asunto(s)

Asunto(s)

RESUMEN

BACKGROUND: Catheter shaping is vital in cerebral aneurysm coil embolization; however, understanding three-dimensional (3D) vascular structures on two-dimensional screens is challenging. Although 3D-printed vascular models are helpful, they demand time, effort, and sterility. This study explores whether mixed-reality (MR) devices displaying 3D computer graphics (3D-CG) can address these issues. METHODS: This study focused on magnetic resonance imaging (MRI) of seven cases of cerebral aneurysms. Head-mounted display (HMD) and spatial reality display (SRD) MR devices were used, and applications for 3D-CG display at a 1:1 scale and a 3D-CG control panel were developed. Catheters shaped using a 3D printer, HMD, and SRD were inserted into hollow models to assess their accessibility and positioning. RESULTS: The concordance rate of the 3D printer and HMD groups in terms of accessibility to the aneurysm was 71.4 %, while that of the 3D printer and SRD group was 85.7 %, and that of the HMD and SRD group was 85.7 %. The concordance rates of positioning in the 3D printer and HMD groups, 3D printer and SRD groups, and HMD and SRD groups were 85.7 %, 85.7 %, and 100 %, respectively. CONCLUSIONS: MR devices facilitate catheter shaping in cerebral aneurysm coil embolization and offer a time-efficient, precise, and sterile alternative to traditional 3D printing methods.

Asunto(s)

RESUMEN

BACKGROUND: Proper catheter placement for convection-enhanced delivery (CED) is required to maximize tumor coverage and minimize exposure to healthy tissue. We developed an image-based model to patient-specifically optimize the catheter placement for rhenium-186 (186Re)-nanoliposomes (RNL) delivery to treat recurrent glioblastoma (rGBM). METHODS: The model consists of the 1) fluid fields generated via catheter infusion, 2) dynamic transport of RNL, and 3) transforming RNL concentration to the SPECT signal. Patient-specific tissue geometries were assigned from pre-delivery MRIs. Model parameters were personalized with either 1) individual-based calibration with longitudinal SPECT images, or 2) population-based assignment via leave-one-out cross-validation. The concordance correlation coefficient (CCC) was used to quantify the agreement between the predicted and measured SPECT signals. The model was then used to simulate RNL distributions from a range of catheter placements, resulting in a ratio of the cumulative RNL dose outside versus inside the tumor, the "off-target ratio" (OTR). Optimal catheter placement) was identified by minimizing OTR. RESULTS: Fifteen patients with rGBM from a Phase I/II clinical trial (NCT01906385) were recruited to the study. Our model, with either individual-calibrated or population-assigned parameters, achieved high accuracy (CCC > 0.80) for predicting RNL distributions up to 24 h after delivery. The optimal catheter placements identified using this model achieved a median (range) of 34.56 % (14.70 %-61.12 %) reduction on OTR at the 24 h post-delivery in comparison to the original placements. CONCLUSIONS: Our image-guided model achieved high accuracy for predicting patient-specific RNL distributions and indicates value for optimizing catheter placement for CED of radiolabeled liposomes.

Asunto(s)

RESUMEN

Peripheral nerve blocks are typically avoided for high-speed tibial plateau fractures due to their ability to mask the paresthesias and pain associated with the feared complication of acute compartment syndrome (ACS). We present a case in which sciatic nerve and adductor canal catheters were placed utilizing low-volume infusions allowing for neurovascular assessment. These catheters served as a valuable portion of the multi-modal pain regimen in this patient with a Schatzker VI tibial plateau fracture.

Asunto(s)

RESUMEN

Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A, particularly for its application in biofilm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efficiency at low concentrations. Its composition, confirmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography (TLC), identified it as an anionic biosurfactant with a significant ionic charge of -14.8 mV. This anionic nature contributes to its biofilm prevention capabilities. The glycolipid showed a high emulsification index (E24) for toluene, gasoline, and soy oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against biofilms formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter surfaces were preconditioned with 2 mg/mL of the glycolipid, biofilm formation was reduced by up to 97% for E. coli and C. albicans and 57% for E. faecalis. These results are particularly significant when compared to the efficacy of conventional surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological tool in reducing biofilm-associated infections on medical devices, demonstrating their promising applicability in healthcare settings.

Asunto(s)

Asunto(s)

RESUMEN

Polymeric elastomers are widely utilized in implantable biomedical devices. Nevertheless, the implantation of these elastomers can provoke a robust foreign body response (FBR), leading to the rejection of foreign implants and consequently reducing their effectiveness in vivo. Building effective anti-FBR coatings on those implants remains challenging. Herein, we introduce a coating-free elastomer with superior immunocompatibility. A super-hydrophilic anti-fouling zwitterionic layer can be generated in situ on the surface of the elastomer through a simple chemical trigger. This elastomer can repel the adsorption of proteins, as well as the adhesion of cells, platelets, and diverse microbes. The elastomer elicited negligible inflammatory responses after subcutaneous implantation in rodents for 2 weeks. No apparent fibrotic capsule formation was observed surrounding the elastomer after 6 months in rodents. Continuous subcutaneous insulin infusion (CSII) catheters constructed from the elastomer demonstrated prolonged longevity and performance compared to commercial catheters, indicating its great potential for enhancing and extending the performance of various implantable biomedical devices by effectively attenuating local immune responses. STATEMENT OF SIGNIFICANCE: The foreign body response remains a significant challenge for implants. Complicated coating procedures are usually needed to construct anti-fibrotic coatings on implantable elastomers. Herein, a coating-free elastomer with superior immunocompatibility was achieved using a zwitterionic monomer derivative. A pure zwitterionic layer can be generated on the elastomer surface through a simple chemical trigger. This elastomer significantly reduces protein adsorption, cell and bacterial adhesion, and platelet activation, leading to minimal fibrotic capsule formation even after six months of subcutaneous implantation in rodents. CSII catheters constructed from the PQCBE-H elastomer demonstrated prolonged longevity and performance compared to commercial catheters, highlighting the significant potential of PQCBE-H elastomers for enhancing and extending the performance of various implantable biomedical devices.

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

OBJECTIVES: Uniportal video-assisted thoracoscopic surgery pneumonectomy (U-VATS-P) is feasible and safe from a perioperative standpoint. How to choose the proper chest tube and drainage method is important in enhanced recovery after surgery (ERAS) protocols. In this study, we aimed to assess the safety of one 8.5-Fr (1Fr = 0.333 mm) pigtail catheter for postoperative continuous open gravity drainage after U-VATS-P. METHODS: We retrospectively reviewed a single surgeon's experience with U-VATS-P for lung cancer from May 2016 to September 2022. Patients were managed with one 8.5-Fr pigtail catheter for postoperative continuous open gravity drainage after U-VATS-P. The clinical characteristics and perioperative outcomes of the patients were retrospectively analyzed. RESULTS: In total, 77 patients had one 8.5-Fr pigtail catheter placed for postoperative continuous open gravity drainage after U-VATS-P for lung cancer. The mean age was 60.9±7.39 (40-76) years; The mean FEV1 was 2.1±0.6 (l/s), and the mean FEV1% was 71.2±22.7. The median operative time was 191.38±59.32 min; the mean operative hemorrhage was 109.46±96.56 ml; the mean duration of postoperative chest tube drainage was 6.80±2.33 days; the mean drainage volumes in the first three days after operation were 186.31±50.97, 321.97±52.03, and 216.44±35.67 ml, respectively; and the mean postoperative hospital stay was 7.90±2.58 days. No patient experienced complications resulting from chest tube malfunction. Ten patients experienced minor complications. One patient with nonlife-threatening empyema and bronchopleural fistula required short rehospitalization for anti-inflammatory therapy and reintubation. Three patients with chylothorax were treated with intravenous nutrition. Four patients had atrial fibrillation that was controlled by antiarrhythmic therapy. Two patients had more thoracic hemorrhagic exudation after the operation, which was found in time and was cured effectively, so they were discharged from the hospital uneventfully after early hemostatic therapy and nutritional support. CONCLUSIONS: All patients in this study received early postoperative rehabilitation, and the rate of relevant complications was low. We therefore recommend a single 8.5-Fr pigtail catheter for postoperative continuous open gravity drainage as an effective, safe and reliable drainage method for the management of U-VATS-P.

Asunto(s)