The recent development of new devices that are significantly less invasive, collectively termed minimally invasive glaucoma surgery, offers new perspective of intraocular pressure reduction with less ...risk, short operating times, and rapid recovery. The aim of this work is to provide a panoramic review of the currently published clinical data to assess the potential role of XEN gel stent (Allergan PLC, Irvine, CA, USA) in the management of glaucoma, which is the only filtering minimally invasive glaucoma surgery device that allows the subconjunctival filtration. The ab interno placement of the XEN gel stent offers an alternative for lowering intraocular pressure in refractory glaucoma as a final step, and in patients intolerant to medical therapy as an early surgical approach with minimum conjunctival tissue disruption, restricted flow to avoid hypotony, and long-term safety.
Purpose
This study was designed to evaluate the clinical outcome and patients’ satisfaction after a 5 year follow-up period for pelvic congestion syndrome (PCS) coil embolization in patients who ...suffered from chronic pelvic pain that initially consulted for lower limb venous insufficiency.
Methods
A total of 202 patients suffering from chronic pelvic pain were recruited prospectively in a single center (mean age 43.5 years; range 27–57) where they were being treated for lower limb varices. Inclusion criteria were: lower limb varices and chronic pelvic pain (>6 months), >6 mm pelvic venous caliber in ultrasonography, and venous reflux or presence of communicating veins. Both ovarian and hypogastric veins were targeted for embolization. Pain level was assessed before and after embolotherapy and during follow-up using a visual analog scale (VAS). Technical and clinical success and recurrence of leg varices were studied. Patients completed a quality questionnaire. Clinical follow-up was performed at 1, 3, and 6 months and every year for 5 years.
Results
Technical success was 100 %. Clinical success was achieved in 168 patients (93.85 %), with complete disappearance of symptoms in 60 patients (33.52 %). Pain score (VAS) was 7.34 ± 0.7 preprocedural versus 0.78 ± 1.2 at the end of follow-up (
P
< 0.0001). Complications were: groin hematoma (
n
= 6), coil migration (
n
= 4), and reaction to contrast media (
n
= 1). Twenty-three cases presented abdominal pain after procedure. In 24 patients (12.5 %), there was recurrence of their leg varices within the follow-up. The mean degree of patients’ satisfaction was 7.4/9.
Conclusions
Coil embolization of PCS is an effective and safe procedure, with high clinical success rate and degree of satisfaction.
Objectives
Benign strictures of the bile duct may be difficult to treat endoscopically due to altered bowel anatomy. Furthermore, recurrence of stenosis and symptoms remains high. The aim of the ...Spanish Prospective Registry BiELLA study was to investigate the safety and efficacy of absorbable stents in the treatment of benign biliary strictures and their outcomes on the medium and long-term follow-up.
Methods
A prospective, multicenter, observational, non-randomized study (the BiELLA study) was conducted from January 2014 to September 2018. One hundred fifty-nine patients with benign biliary strictures, mostly postsurgical, were enrolled for implantation of absorbable biliary stents in the 11 participating Spanish tertiary hospitals. The average patient follow-up was 45.4 ± 15.9 months (range, 12–60 months). The follow-up data included symptoms, biochemical parameters, and ultrasound images at 1, 6, and 12 months and then yearly for up to 60 months.
Results
The immediate technical and clinical success rates were 100%. In all patients, stent placement resulted in improvement of clinical symptoms and biochemical parameters. The primary mean patency for stent was 86.7, 79.6, and 78.9% at 12, 36, and 60 months, respectively (95% CI). Biliary restenosis and occlusion occurred in 40 (26.6%) patients. Of the 40 patients, 18 (12%) patients were treated with a second stent and 22 (14.6%) patients had operative repair of the recurrent strictures. There were no major complications associated with stent implantation.
Conclusions
Implantation of an absorbable polydioxanone biliary stent is safe and effective for treatment of benign biliary strictures refractory to balloon dilatation or other biliary intervention.
Key Points
• Percutaneous implantation of biodegradable prostheses for the treatment of benign postsurgical biliary strictures is a safe and effective procedure.
• More than 75% of the patients presented patency of the stented biliary tree at 5 years follow-up.
• Absorbable stents improved clinical symptoms and signs (jaundice, itching, fever), and laboratory parameters in a few days after stent placement.
Stenting technique is employed worldwide for treating atherosclerotic vessel and tracheal stenosis. Both diseases can be treated by means of metallic stents which present advantages but are affected ...by the main problem of restenosis of the stented area. In this study we have built a rabbit trachea numerical model and we have analyzed it before and after insertion and opening of two types of commercial stent: a Zilver
®
Flex
TM
Stent and a WallStent
TM
. In experimental parallel work, two types of stent were implanted in 30 New Zealand rabbits divided in two groups of 10 animals corresponding to each stent type and a third group made up of 10 animals without stent. The tracheal wall response was assessed by means of computerized tomography by endoscopy, macroscopic findings and histopathological study 90 days after stent deployment. Three idealized trachea models, one model for each group, were created in order to perform the computational study. The animal model was used to validate the numerical findings and to attempt to find qualitative correlations between numerical and experimental results. Experimental findings such as inflammation, granuloma and abnormal tissue growth, assessed from histomorphometric analyses were compared with derived numerical parameters such as wall shear stress (WSS) and maximum principal stress. The direct comparison of these parameters and the biological response supports the hypothesis that WSS and tensile stresses may lead to a greater tracheal epithelium response within the stented region, with the latter seeming to have the dominant role. This study may be helpful for improving stent design and demonstrates the feasibility offered by in-silico investigated tracheal structural and fluid dynamics.
Purpose
Lymph node metastases significantly worsen the prognosis in cervical carcinoma. Risk factors—pathological and patient related—could select patients at high risk for lymph node involvement.
...Methods
This retrospective analysis was performed by analyzing data from patients with cervical carcinoma treated between 2000 and 2017 at the Department of Obstetrics and Gynecology of the University Hospital Ulm.
Results
In total, 261 patients with cervical carcinoma (International Federation of Gynecology and Obstetrics (FIGO) stage IA–IIB) and lymphadenectomy with at least 10 removed lymph nodes were available for analysis. Overall, 86 (33.0%) patients had lymph node metastases; 73 patients had pelvic lymph node metastases only and 13 patients had both pelvic and paraaortic lymph node metastases. Lymph node metastases were found most often in the region of the external iliac artery and obturator fossa, with 57.0% and 54.7% of all 86 node-positive patients, respectively. Univariable analyses showed that presence of lymph node metastases was significantly associated with both preoperative FIGO stage (
p
= 0.001) and final pathological tumor stage (
p
< 0.001), status of resection margin (
p
= 0.002), lymphovascular space invasion (LVSI), (
p
< 0.001) and vascular space invasion, (
p
< 0.001). In a multivariable logistic regression model with presence of lymph node metastases (yes/no) as binary response variable, only LVSI (
p
< 0.001) and body mass index (BMI), (
p
= 0.035) remained as significant independent predictors of lymph node involvement. Subgroup analyses showed that LVSI was a significant predictive factor for lymph node involvement in patients with a preoperatively assessed FIGO stage < IIB (
p
< 0.001), but not for patients with a preoperatively assessed FIGO stage ≥ IIB (
p
= 0.122).
Conclusions
The risk factor LVSI should play an important role in deciding whether an individualized therapy concept is based on escalating or deescalating treatment. In future, the sentinel concept could reduce morbidity and at the same time provide an important prognostic assessment for a subset of cervical cancer patients.
Summary
Fiducial markers are used in correlated light and electron microscopy (CLEM) to enable accurate overlaying of fluorescence and electron microscopy images. Currently used fiducial markers, ...e.g. dye‐labelled nanoparticles and quantum dots, suffer from irreversible quenching of the luminescence after electron beam exposure. This limits their use in CLEM, since samples have to be studied with light microscopy before the sample can be studied with electron microscopy. Robust fiducial markers, i.e. luminescent labels that can (partially) withstand electron bombardment, are interesting because of the recent development of integrated CLEM microscopes. In addition, nonintegrated CLEM setups may benefit from such fiducial markers. Such markers would allow switching back from EM to LM and are not available yet.
Here, we investigate the robustness of various luminescent nanoparticles (NPs) that have good contrast in electron microscopy; 130 nm gold‐core rhodamine B‐labelled silica particles, 15 nm CdSe/CdS/ZnS core–shell–shell quantum dots (QDs) and 230 nm Y2O3:Eu3+ particles. Robustness is studied by measuring the luminescence of (single) NPs after various cycles of electron beam exposure. The gold‐core rhodamine B‐labelled silica NPs and QDs are quenched after a single exposure to 60 ke− nm–2 with an energy of 120 keV, while Y2O3:Eu3+ NPs are robust and still show luminescence after five doses of 60 ke− nm–2. In addition, the luminescence intensity of Y2O3:Eu3+ NPs is investigated as function of electron dose for various electron fluxes. The luminescence intensity initially drops to a constant value well above the single particle detection limit. The intensity loss does not depend on the electron flux, but on the total electron dose. The results indicate that Y2O3:Eu3+ NPs are promising as robust fiducial marker in CLEM.
Lay Description
Luminescent particles are used as fiducial markers in correlative light and electron microscopy (CLEM) to enable accurate overlaying of fluorescence and electron microscopy images. The currently used fiducial markers, e.g. dyes and quantum dots, loose their luminescence after exposure to the electron beam of the electron microscope. This limits their use in CLEM, since samples have to be studied with light microscopy before the sample can be studied with electron microscopy. Robust fiducial markers, i.e. luminescent labels that can withstand electron exposure, are interesting because of recent developments in integrated CLEM microscopes. Also nonintegrated CLEM setups may benefit from such fiducial markers. Such markers would allow for switching back to fluorescence imaging after the recording of electron microscopy imaging and are not available yet.
Here, we investigate the robustness of various luminescent nanoparticles (NPs) that have good contrast in electron microscopy; dye‐labelled silica particles, quantum dots and lanthanide‐doped inorganic particles. Robustness is studied by measuring the luminescence of (single) NPs after various cycles of electron beam exposure. The dye‐labelled silica NPs and QDs are quenched after a single exposure to 60 ke− nm–2 with an energy of 120 keV, while lanthanide‐doped inorganic NPs are robust and still show luminescence after five doses of 60 ke− nm–2. In addition, the luminescence intensity of lanthanide‐doped inorganic NPs is investigated as function of electron dose for various electron fluxes. The luminescence intensity initially drops to a constant value well above the single particle detection limit. The intensity loss does not depend on the electron flux, but on the total electron dose. The results indicate that lanthanide‐doped NPs are promising as robust fiducial marker in CLEM.
. The Monte Carlo simulation software is a valuable tool in radiation therapy, in particular to achieve the needed accuracy in the dose evaluation for the treatment plans optimisation. The current ...challenge in this field is the time reduction to open the way to many clinical applications for which the computational time is an issue. In this manuscript we present an innovative GPU-accelerated Monte Carlo software for dose valuation in electron and photon based radiotherapy, developed as an update of the FRED (Fast paRticle thErapy Dose evaluator) software.
. The code transports particles through a 3D voxel grid, while scoring their energy deposition along their trajectory. The models of electromagnetic interactions in the energy region between 1 MeV-1 GeV available in literature have been implemented to efficiently run on GPUs, allowing to combine a fast tracking while keeping high accuracy in dose assessment. The FRED software has been bench-marked against state-of-art full MC (FLUKA, GEANT4) in the realm of two different radiotherapy applications: Intra-Operative Radio Therapy and Very High Electron Energy radiotherapy applications.
. The single pencil beam dose-depth profiles in water as well as the dose map computed on non-homogeneous phantom agree with full-MCs at 2% level, observing a gain in processing time from 200 to 5000.
. Such performance allows for computing a plan with electron beams in few minutes with an accuracy of ∼%, demonstrating the FRED potential to be adopted for fast plan re-calculation in photon or electron radiotherapy applications.
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