Stent Misplacement Research Articles

Balloon catheter-assisted rescue for misplacement of lumen-apposing stent across the pylorus in endoscopic ultrasound-guided transduodenal drainage of walled-off necrosis.

Balloon catheter-assisted rescue for misplacement of lumen-apposing stent across the pylorus in endoscopic ultrasound-guided transduodenal drainage of walled-off necrosis.

Safety and efficacy of ultrasound-assisted bedside ureteric stent placement A prospective, single-institution study.

Previous studies have demonstrated the feasibility of bedside placement of ureteric stents; however, they have traditionally required two skilled operators and were associated with some stent malposition especially for proximal ureteric obstruction. We sought to investigate the efficacy and safety of a modified technique for ultrasound-assisted bedside ureteric stent insertion without the presence of a skilled assist. A single institution prospective study was performed from April-August 2023. Indications for stenting included infection, renal insufficiency, or intractable colic. Exclusion criteria included age <18 years, hemodynamic instability, and patients with history of chronic pain. Point-of-care ultrasound (POCUS) was used to confirm wire placement in the kidney and presence of a hydronephrotic drip from a 5 French ureteric catheter was used to confirm placement beyond the level of obstruction. Of 28 patients, all patients underwent successful bedside ureteric stent placement. Mean age was 64.9 years and mean body mass index (BMI) was 33.2. Proximal ureter obstruction was present in 52% of patients and mid/distal obstruction in 48%. In cases with obstructing stones, the mean stone size was 8.1 mm with a range of 4-15 mm. Infection was the indication for stent placement in most patients (71%), followed by pain (4%) and acute kidney injury (AKI) (4%). All patients who underwent successful stent placement had presence of hydronephrotic drip from the ureteric catheter. Ultrasound-assisted bedside ureteric stent insertion without a skilled assist is a safe and feasible option for management of acute ureteral obstruction. Presence of hydronephrotic drip can indicate successful access beyond the level of obstruction as an alternative to POCUS.

Misplaced intraspinal venous stent causing cauda equina syndrome: illustrative case.

Endovenous stents for deep venous thrombosis treatment can be unintentionally placed in the spinal canal, resulting in neurological deficit. The authors report the case of a patient presenting to our institution with intraspinal misplacement of an endovenous stent, resulting in cauda equina syndrome. The authors also performed a systematic literature review, evaluating the few previously reported cases. This review was performed according to the updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In four of five cases describing stent misplacement into the spinal canal, the authors report that only anteroposterior monoplanar imaging modalities were utilized for venous localization and stent deployment. The anteroposterior plane cannot assess the relative depth of structures, nor can it distinguish between superimposed structures well. Therefore, the use of biplanar imaging should at least be considered before stent deployment, as intraspinal stent placement can lead to disastrous consequences. This report should serve as an impetus for the use of biplanar or three-dimensional imaging modalities for iliac venous stent placement. Additionally, this work should increase spine surgeons' awareness about management and operative techniques when faced with this complication.

Five-Year Outcomes of Single Trabecular Microbypass Stent (iStent®) Implantation with Phacoemulsification in Korean Patients.

This study reports the long-term intraocular pressure (IOP)-lowering efficacy and safety of a singletrabecular microbypass stent(iStent®; Glaukos Corp., San Clemente, CA, USA) for medically controlled open-angleglaucoma in Korean patients. This retrospective observational study included 42 eyes of 35 patients with primary open-angle glaucoma (POAG). All subjects underwent single first-generation iStent® implantation with phacoemulsification by a single surgeon with 5years follow-up. The primary outcomes were changes in IOP and the number of antiglaucoma medications compared to the preoperative values. The secondary outcome was the proportion of eyes with IOP ≤ 18mmHg without medication, ≤ 15mmHg without medication, and ≤ 18mmHg with or without medication. Adverse events and need for secondary glaucoma surgery were also recorded. The mean IOP decreased from 15.8 ± 2.8 to 13.8 ± 1.7mmHg and the mean number of medications was reduced from 2.24 ± 1.18 to 0.83 ± 1.12, respectively, at year5. At 3 and 5years, 80.6% and 78.6% of eyes, respectively, were receiving fewer medications than preoperative numbers. In contrast, only 50% of eyes on four preoperative medications showed medication reductions at 5years. At years3 and 5, 61.3% and 53.5% of eyes achieved IOP ≤ 18mmHg without medication, whereas 90.3% and 89.3% of eyes achieved ≤ 18mmHg regardless of medication use, respectively. Four eyes required additional glaucoma surgery (two Ahmed glaucoma valve implantations, one trabeculectomy, and one XEN45 Gel Stent implantation), and all were receiving four preoperative antiglaucoma medications. Transient IOP elevation (14.3%) was the most common complication, followed by five hyphema, one stent obstruction, one stent malposition, and one severe anterior chamber reaction. This study demonstrated a good safety profile and sustained IOP reduction after the implantation of a single trabecular microbypass stent (iStent®) with phacoemulsification in Korean patients. The majority of subjects with POAG showed a relatively good response; however, eyes receiving a higher number of medications preoperatively (especially four medications) had difficulty achieving a low target IOP.

Uncommon Malpositioned Inserted Biliary Stent Causing Common Bile Duct to Portal Vein Fistula: Case Report

Endoscopic biliary stent is a common practice in recent years. One of the complications might occur is stent malposition. A 31 years old male with obstructive jaundice secondary to gallstone, presented with persistent upper right quadrant abdominal pain immediately after biliary stenting. During evaluation, biliary stent was found in the portal vein, he immediately underwent repair laparoscopic converted to laparotomy due to obscured stent. Intraoperative findings include fistula in the common bile duct (CBD) to portal vein. Malposition of biliary stent is common occurrence. However, only 5% malposition to proximal and &lt;1% cause perforation or fistula. Anatomical variation of extrahepatic biliary system is common and might be a contributing factor. Thus, adequate knowledge of the anatomical variation helps in stent placement and preventing associated complication. We report a rare case of CBD stent malposition to proximal portal vein with fistula.

Efficacy and safety of fetal posterior cerebral artery stented coil embolization for fetal posterior cerebral aneurysms.

Aneurysms at the origin of the fetal posterior cerebral artery (fPCA) often show fPCA bifurcation from the aneurysm dome, impeding complete embolization and dense coil packing. The recanalization rate for fPCA aneurysms is therefore high. This study aimed to evaluate the efficacy and safety of stenting into fPCA for aneurysms with fPCA incorporated into the aneurysm to determine whether stenting can provide effective embolization results and prevent recanalization. A total of 19 consecutive coil embolization procedures between February 2012 and June 2022 for unruptured fPCA aneurysms with fPCA branching from the dome of the aneurysm were divided into two groups: non-stenting (NS) group (n = 11) and stenting into fPCA (PS) group (n = 8). Data were obtained retrospectively and compared regarding embolization results, complications, and recanalization. Compared with the NS group, the PS group achieved significantly higher complete occlusion rate and packing density (p < 0.001, p = 0.01, respectively). No symptomatic complications were observed in the PS group. Both immediately after stenting and at the 1-year follow-up, no stent kinking, stenosis, occlusion, or malposition were observed in any patients in the PS group. During 1-year follow-up, the cumulative minor and major recanalization-free rate after coil embolization for fPCA aneurysms were significantly higher in the PS group compared with the NS group (p = 0.022, 0.0024, respectively). Stenting into fPCA for aneurysms with fPCA incorporated into the aneurysm achieved high-density complete embolization without increasing complications, and prevented recanalization. The fPCA stent-assisted coil embolization can offer an alternative treatment for fPCA aneurysms.

Four-Year Outcome of XEN 45 Gel Stent Implantation in a Swedish Population.

To report the long-time success rate of XEN 45 gel stent implantation in a Scandinavian population. This was a retrospective single-center analysis of all patients undergoing XEN 45 stent surgery between December 2015 and May 2017. The main outcome was success rate according to several definitions of success. Subgroup analysis was performed. Secondary outcomes were change in intraocular pressure (IOP) and number of IOP-lowering agents. Need for secondary glaucoma surgery, needling rate and complications were recorded. A total of 103 eyes could be evaluated after four years. Mean age was 70.6 years. Primary open-angle glaucoma (POAG) accounted for 46.6% and exfoliative glaucoma (PEXG) for 39.8%. Mean IOP dropped from 24.0 to 15.9 mmHg (p<0.001) and IOP-lowering agents from 3.5 to 1.5 (p<0.001). The success rate with individual target pressures after four years was 43.7%. Secondary glaucoma surgery was performed in 45 (43.7%) of cases. Combined cases (n=12) were not statistically different to stand-alone procedures (p=0.28). No difference between PEXG and POAG could be detected (p=0.44). During the learning curve, stent misplacement was common and resulted in worse outcome for less experienced surgeons. The overall success rate of XEN 45 gel stent surgery in the present cohort is relatively low in a long-time follow-up under the given circumstances if all initial patients are included to follow-up. The influence of the surgeon's learning curve is obvious, and improvement in success can be expected when used by experienced and high-volume surgeons. No significant differences were found in PEXG compared to POAG or in XEN surgery combined with cataract surgery compared to stand-alone.

Additional rescue stenting with Neuroform Atlas stents during stent-assisted coiling of saccular aneurysms

ObjectiveOverlapping stenting is sometimes attempted during endovascular treatment of cerebral aneurysm as a rescue for coil herniation, stent mal-positioning, or in-stent thrombosis. We retrospectively evaluated the efficacy and safety of additional rescue stenting (ARS) in telescoping fashion with Neuroform Atlas stent (NAS) during stent-assisted coiling of saccular aneurysms. MethodsWe collected clinical and radiological data of patients with saccular aneurysms treated with ARS using NASs between March 2018 and December 2021. Y or X-stent-assisted coiling technique was excluded. ResultsEighteen unruptured and 5 ruptured aneurysms in 23 patients were treated with ARS using NASs. Sizes of aneurysms ranged from 2.0 mm to 10.0 mm (mean: 5.0 mm). Immediate angiographic results were complete occlusion in 11 aneurysms, residual neck in 4 aneurysms, and residual sac in 8 aneurysms. Peri-operative morbidity was 4.3 %. Nineteen of 23 patients underwent follow-up conventional angiography (mean, 9.9 months). Results showed progressive occlusion in 10 (52.6 %) cases and asymptomatic in-stent stenosis in 3 (15.8 %) cases. At the end of the observation period (mean, 17.4 months), all 18 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS of 0), except one (mRS of 1). Of five patients with subarachnoid hemorrhage, four had a favorable outcome (mRS of 0–1), while the other one was dependent (mRS of 4). ConclusionIn this report on 23 patients, ARS with NASs for treating saccular aneurysms showed good technical safety with favorable clinical and angiographic outcomes. However, delayed in-stent stenosis was not uncommon. Thus, regular imaging follow-up is required.

Fluoroscopic-guided retrograde transurethral ureteric stent insertion case series - Technical challenges and solutions

IntroductionFluoroscopic-guided retrograde ureteric stent exchange is a commonly performed procedure at our institution for patients with treated gynaecological malignancy. Technical challenges are often met during the procedure. This approach is well-tolerated and does not require general anaesthetic. Routine exchange is required every 16–20 weeks. Presentation of casesWe describe the technique of fluoroscopic-guided retrograde transurethral ureteric stent exchange and outline potential technical pitfalls through a series of recent cases at our institution. Challenges encountered include stent encrustation, stent malposition, tangled stents and loss of access. DiscussionThe case series demonstrates a variety of solutions to challenging technical situations including manual breakdown of luminal debris, stent repositioning and snaring techniques, and methods for overcoming loss of access. Successful outcomes were achieved in the majority of cases. ConclusionFluoroscopic-guided retrograde ureteric stent exchange is a challenging technique, not universally performed in all interventional departments. The technique is generally well tolerated and avoids the need for general anaesthesia.

Nutritional Status and the Outcomes of Endoscopic Stenting in Benign and Malignant Diseases of Esophagus

Endoscopic stenting (ES) is a widely known method for palliative dysphagia treatment in esophageal strictures. Esophageal cancer is often associated with advanced malnutrition, which may increase the risk of complications of the procedure. The aim of this study was to evaluate complication rates and the impact of nutritional status on the outcomes of ES. A single-center retrospective study was conducted at Copernicus Hospital in Gdańsk, Poland. Adult patients who underwent endoscopic stenting between February 2014 and December 2018 were included. The influence of patient characteristics (age, sex, indications for esophageal stenting, and location of stenosis) and nutritional status (BMI, NRS 2002, GLIM, and dysphagia score) on complication rates and survival were analyzed. Eighty-one patients (69% men) were enrolled in the study. In 69%, the indication for ES was malignancy (mainly esophageal cancer). The median dysphagia score significantly decreased from 2.8 to 0.6 after the procedure (p < 0.001). Complications were observed in 27% (n = 22) of the patients. Early complications were bleeding (2.5%), stent unexpansion (2.5%), and stent migration during the procedure (3.7%). There were no early fatal complications of the procedure. Late complications included: stent migration (6.2%), tissue overgrowth (6.2%), food impaction (2.2%), fistula formation (3.7%), bleeding (3.7%), and stent malposition (1.2%). A total of 76% of the participants scored ≥ 3 points in nutritional screening (NRS2002) and 70% were diagnosed with severe malnutrition (GLIM -stage 2). A stent diameter of < 2.2 cm compared with ≥ 2.2 was associated with a higher rate of migrations (15.5% vs. 2.5%). The median survival time in the malignant group was 90 days. Histopathological diagnosis and patients' nutritional status (BMI, NRS 2002, GLIM, and dysphagia score) had no significant effect on complication rates and survival after esophageal stent insertion. Endoscopic stenting is a relatively safe procedure for the palliative treatment of esophageal strictures. Severe malnutrition, although common, does not affect the outcomes of the procedure.

“Floating” Stent in a Coronary Aneurysm Presenting as ST-Elevation Myocardial Infarction

Coronary artery aneurysm (CAA) presenting as an ST-elevation myocardial infarction (STEMI) represents a clinical challenge due to the technical difficulties in the percutaneous management of this specific situation. Appropriate treatment for CAA depends on the precise clinical situation and consists of medical management, surgical resection, or/and stent placement. The high rate of complications during percutaneous intervention (distal thrombus embolization, no-reflow phenomenon, stent malposition, or dissection) makes emergent surgery a frequent situation in these cases. We present the case of a 50-year-old man with a STEMI due to thrombotic occlusion of CAA. Specific angiographic techniques and intracoronary imaging help with the percutaneous management of acute thrombotic occlusions in CAA, providing a less invasive approach than emergent surgery.

Feasibility and safety of a new dedicated biliary stent for EUS-guided hepaticogastrostomy: The FIT study (with video).

EUS-guided biliary drainage (BD) through hepaticogastrostomy (HGS) is an option in case of ERCP failure. Available data suggest that this procedure may be challenging with possible severe adverse events (AEs) mainly due to stent migration. The aim of our pilot study was to prospectively assess the technical and clinical outcomes of EUS-HGS using a new dedicated partially covered self-expandable metal stent with anti-migratory systems. This is a single-center prospective study enrolling patients with malignant biliary obstruction undergoing EUS-HGS after failed ERCP, between June 2020 and March 2021. The primary endpoint was the technical success rate. Evaluation of specific stent-related technical features as compared with commonly used self-expandable metal stent, clinical success rate, and procedure-related AEs was also assessed. Twenty-two patients (15%-68.2%, female; mean age, 66.0 ± 10.0) were enrolled in the study analysis. Different causes of ERCP failure were infiltration of papilla by neoplastic tissue (4, 18.2%), unreachable papilla for duodenal stricture (9, 40.9%), surgically altered anatomy with Roux-en-Y reconstruction (4, 18.2%), and incomplete BD after transpapillary stent placement (5, 22.7%). Technical success was achieved in all patients, in a mean procedural time of 43.3 ± 26.8 min. Technical features were graded as high or medium in all cases. The clinical success rate was 91% (20/22, mean follow-up: 10.8 ± 3.1 months). There were no cases of stent misplacement or stent migration. Three (13.6%) cases of a hepatic abscess requiring percutaneous drainage and systemic antibiotics were reported, with no impact on clinical success and following oncologic treatments. No deaths occurred. EUS-HGS with a new dedicated stent with anti-migratory systems is feasible and effective, preventing stent migration, and misplacement. Although the persistent procedural challenges, dedicated devices may contribute to outcomes improvement and procedure diffusion.

A misplacement of a ureteral stent into the abdominal aorta: a case report of a rare retrograde ureteral stenting complication

BackgroundCervical cancer is often associated with malignant ureteral obstruction and consequent hydronephrosis. Hydronephrosis caused in this way can be resolved by placing ureteral stents or performing a percutaneous nephrostomy. Complications that may occur during the retrograde ureteral stent placement are usually mild, but serious complications such as stent migration into the cardiovascular system are also possible. Here we present an unusual case where a ureteral stent entered the abdominal aorta during the cystoscopic ureteral stenting, which was resolved by a cystoscopic stent removal kept in check by endovascular catheters.Case presentationsThe 48-year-old female patient was treated in the regional secondary healthcare facility due to bilateral hydronephrosis caused by cervical cancer. The patient had bilateral percutaneous nephrostomies and ureteral stents. Due to the calcification of the left ureteral stent, an urethrorenoscopy with lithotripsy of the calculus in the left ureter was performed in the regional secondary healthcare facility, and the ureteral stent was cystoscopically replaced. The control radiography of the urinary tract showed a misplacement of the left ureteral stent, and a computed tomography showed that the stent was located in the abdominal aorta. The patient was referred to the University Clinical Center of Serbia, where a ureteral stent was cystoscopically removed from the abdominal aorta under the control of endovascular catheters. The patient was in good general condition at all times, with no signs of bleeding, and she was discharged from the hospital on the fourth postoperative day.ConclusionsThe migration of a ureteral stent into the abdominal aorta and the cardiovascular system in general is a rare type of ureteral stenting complication whose treatment requires a multidisciplinary approach. In order to prevent such complications, it is necessary to strictly adhere to the indications for the ureteral stent placement in the case of malignant ureteral obstruction. Also, this procedure should be performed according to the current guidelines and controlled by an X-ray or ultrasound.

Favourable Short- to Mid-Term Outcome after PDA-Stenting in Duct-Dependent Pulmonary Circulation.

Background. Stenting of patent ductus arteriosus (PDA) is a minimally invasive catheter-based temporary palliative procedure that is an alternative to a surgical shunt in neonates with duct-dependent pulmonary perfusion. Methods. An observational, single-centre, cross-sectional study of patients with duct-dependent pulmonary perfusion undergoing PDA-stenting as a stage I procedure and an analysis of short- to mid-term follow-up until a subsequent surgical procedure (stage II), with a focus on the interstage course. Results. Twenty-six patients were treated with PDA-stenting at a median (IQR) age of 7 (4–10) days; 10/26 patients (38.5%) (6/10 single pulmonary perfusion) were intended for later univentricular palliation, 16/26 patients (61.5%) (13/16 single pulmonary perfusion) for biventricular repair. PDA diameter was 2.7 (1.8–3.2) mm, stent diameter 3.5 (3.5–4.0) mm. Immediate procedural success was 88.5%. The procedure was aborted, switching to immediate surgery after stent embolisation, malposition or pulmonary coarctation in three patients (each n = 1). During mid-term follow-up, one patient needed an additional surgical shunt due to severe cyanosis, while five patients underwent successful catheter re-intervention 27 (17–30) days after PDA-stenting due to pulmonary hypo- (n = 4) or hyperperfusion (n = 1). Interstage mortality was 8.6% (2/23), both in-hospital and non-procedure-related. LPA grew significantly (p = 0.06) between PDA-stenting and last follow-up prior to subsequent surgical procedure (p = 0.06). RPA Z-scores remained similar (p = 0.22). The subsequent surgical procedure was performed at a median age of 106 (76.5–125) days. Conclusions. PDA-stenting is a feasible, safe treatment option, with the need for interdisciplinary decision-making beforehand and surgical backup afterwards. It allows adequate body and pulmonary vessel growth for subsequent surgical procedures. Factors determining the individual patient’s course should be identified in larger prospective studies.

Technical feasibility and clinical success of direct "free hand" EUS-guided gastroenterostomy in patients with gastric outlet obstruction.

Background and study aims Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) with lumen-apposing metal stents (LAMS) appears to be a promising intervention in management of gastroduodenal out obstruction (GOO), particularly for patients for whom surgery is high risk or in a palliative setting. This study aimed to evaluate the technical feasibility, procedure-associated adverse events (AEs), and clinical outcome of direct “free hand” EUS-GE. Patients and methods This retrospective two-center study included patients who underwent direct “free hand” EUS-GE (April 2017 to March 2021) investigating technical success (correctly placed LAMS), clinical outcome (successful oral nutrition), and management of procedure-associated AEs. “Free hand” was defined as the use of the electrocautery enhanced stent delivery system alone without additional guidewire-assistance for EUS-GE creation. Results Forty-five patients (58 % women/42 % men; mean age 65 years) with malignant (n = 39), benign (n = 4) or unclear (n = 2) GOO underwent direct “free hand” EUS-GE. The technical success rate was 98 % (44/45). Of the patients, 95% (42/44) had less vomiting and increased ability to tolerate oral food intake after the intervention. In one patient, a second EUS-GE was necessary to achieve sufficient clinical improvement. Procedure-associated AEs were observed in 24 % (11/45) of cases including stent misplacement (n = 7), leakage (n = 1), development of a gastrojejunocolic fistula (n = 1), and bleeding (n = 2), which could be all managed endoscopically. Conclusions Direct EUS-GE has a favorable risk-benefit profile for patients with GOO, showing high technical success rates, manageable AEs, and rapid symptom relief.

Effect and prognosis of new type of re-dilated stent in the treatment of pulmonary artery bifurcation stenosis

the early and med-term follow-up results and technical points of new re-dilated stent in the treatment of pulmonary artery bifurcation opening stenosis, and explore its feasibility and advantages. From March 2019 to October 2020, 10 children [5 males, mean age (7±3) years], mean weight 18.75(13.35,23.05) kg with pulmonary artery bifurcation opening stenosis were treated with new re-dilated stents in the Central China Fuwai Hospital. Including 5 cases of tetralogy of Fallot, 4 cases of pulmonary atresia, 1 case of anomalous origin of coronary artery, all children were given new re-dilated stent implantation. Echocardiography, chest X-ray and electrocardiogram were performed 1 day, 3, 6, 12 months after intervention. Pulmonary artery CTA was performed after 6 or 12 months to evaluate the results, including restenosis, malposition and rupture. A total of 16 stents were implanted in 10 children, 5 cases had simultaneous stenosis of bifurcation openings of pulmonary arteries, and 1 stent was implanted in each of the left and right pulmonary artery openings. The pressure of right ventricular and gradient was significantly decreased immediately after intervention, from preoperative (38-80) mmHg(1 mmHg=0.133 kPa) to postoperative (0-22) mmHg, only one patient's pressure gradient is over 20 mmHg (22 mmHg), and all cases discharged successfully. Stent restenosis, malposition, fracture and other abnormalities were not observed in follow-up. Stents implantation for patients with pulmonary artery bifurcation opening stenosis is very more difficult. A good strategy can ensure that the intervention is safe and effective. It not only avoids the risk of repeated surgery, but also achieves good med-term follow-up results.

Safe oesophageal stent deployment using a checklist system instead of fluoroscopy.

Stenting is the management of choice for many benign and malignant oesophageal conditions and in the interest of safety stent insertion has traditionally been performed under fluoroscopic guidance. But this incurs additional expense, time, radiation risk and for the foreseeable future, an increased risk of Covid infection to patients and healthcare personnel. We describe a protocol that obviates the need for fluoroscopic guidance, relying instead on a systematic checklist to ensure safe positioning of the guidewire and the accurate positioning of the stent. The aim of this retrospective study was to review our experience of stent insertion employing a checklist system and compare our outcomes with outcomes using fluoroscopy in the literature. We performed a retrospective review of a prospectively collected dataset of all patients undergoing oesophageal stent insertion between December 2007 and October 2019. The primary end points were patient safety parameters and complications of stent insertion. Total of 163 stents were deployed of which 93 (57%) were in males and the median age was 67.9years (25-92years). Partially covered self-expanding metallic stents (SEMS) were used in 80% of procedures (130/163). One hundred nineteen stents (73%) were for malignant strictures and 127 (78%) were deployed for strictures in the lower third of the oesophagus. There was no stent misplacement, injury, perforation or death associated with the procedure. Vomiting was the main post-operative complication (14%). Severe odynophagia necessitated stent removal in 3 patients. Stent migration occurred in 17 (10%) procedures with a mean time to stent migration of 6.4weeks (range 1-20weeks). Oesophageal stent placement without fluoroscopy is safe provided that a strict checklist is adhered to. The outcomes are comparable to the results of fluoroscopic stent placement in the literature, with considerable saving in time, cost, personnel, and risks of radiation and Covid exposure.

Effect of flow diverter stent malposition on intracranial aneurysm hemodynamics-An experimental framework using stereoscopic particle image velocimetry.

BackgroundFlow-diverting stents are increasingly used for the minimally-invasive treatment of intracranial aneurysms. However, a correct positioning of such devices can be challenging due to varying vessel diameters as well as the complex anatomy of the neurovasculature. As a consequence, unsuccessful treatment outcomes are increasingly reported requiring an improvement of the understanding of stent-induced flow modification.MethodsTo evaluate the effect of different degrees of flow diverter stent malposition on intra-aneurysmal hemodynamic changes, a controlled hemodynamic configuration was created using an idealized intracranial aneurysms model. Afterwards, four different treatment scenarios were reproduced comprising of 1) the ideal treatment, 2) an insufficient wall apposition in the region of the ostium, 3) a distorted device migrating into the aneurysm sac and 4) an inaccurately deployed stent due to wrong release location. For the assessment of the individual flow modifications, high-resolution stereoscopic particle image velocimetry (PIV) measurements were carried out.ResultsThe analysis of the precise in-vitro PIV measurements reveals that in all cases a considerable reduction of the cycle-averaged and peak-systolic velocity was obtained. Compared to the untreated aneurysm configuration, the flow reduction ranged from 63% (scenario 4) up to 89% (scenario 3). The ideal treatment reached a reduction of 78%, which is known to be sufficient for a successful therapy. However, inaccurate device positioning leads to increased oscillating flow towards the lateral directions reducing the chances of sufficient thrombus formation.ConclusionsHigh-resolution in-vitro PIV measurements enable an accurate quantification of the treatment efficacy for flow-diverting devices. Furthermore, insufficient treatment outcomes can be reproduces allowing for an assessment of intra-aneurysmal hemodynamic changes.

Four-Dimensional Computed Tomography-Guided Valve Sizing for Transcatheter Pulmonary Valve Replacement.

The measurements of the right ventricle (RV) and pulmonary artery (PA), for selecting the optimal prosthesis size for transcatheter pulmonary valve replacement (TPVR), vary considerably. Three-dimensional (3D) computed tomography (CT) imaging for device size prediction is insufficient to assess the displacement of the right ventricular outflow tract (RVOT) and PA, which could increase the risk of stent misplacement and paravalvular leak. The aim of this study is to provide a dynamic model to visualize and quantify the anatomy of the RVOT to PA over the entire cardiac cycle by four-dimensional (4D) cardiac CT reconstruction to obtain an accurate quantitative evaluation of the required valve size. In this pilot study, cardiac CT from sheep J was chosen to illustrate the procedures. 3D cardiac CT was imported into 3D reconstruction software to build a 4D sequence which was divided into eleven frames over the cardiac cycle to visualize the deformation of the heart. Diameter, cross-sectional area, and circumference of five imaging planes at the main PA, sinotubular junction, sinus, basal plane of the pulmonary valve (BPV), and RVOT were measured at each frame in 4D straightened models prior to valve implantation to predict the valve size. Meanwhile, dynamic changes in the RV volume were also measured to evaluate right ventricular ejection fraction (RVEF). 3D measurements at the end of the diastole were obtained for comparison with the 4D measurements. In sheep J, 4D CT measurements from the straightened model resulted in the same choice of valve size for TPVR (30 mm) as 3D measurements. The RVEF of sheep J from pre-CT was 62.1 %. In contrast with 3D CT, the straightened 4D reconstruction model not only enabled accurate prediction for valve size selection for TPVR but also provided an ideal virtual reality, thus presenting a promising method for TPVR and the innovation of TPVR devices.

Adverse events associated with AXIOS stents: Insights from the manufacturer and user facility device experience database.

ABSTRACTBackground and Objectives:The AXIOS stent is indicated for transgastric or transduodenal drainage of symptomatic pancreatic pseudocysts and symptomatic walled off necrosis. The AXIOS stent functions as a conduit which allows solid and liquid pancreatic fluid collections (PFC) contents to pass into the luminal GI tract and also allows the passage of standard and therapeutic endoscopes into the PFC to perform endoscopic debridement. We aim to investigate the number and type of complications associated with AXIOS stents.Materials and Methods:We analyzed postmarketing surveillance data from the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database January 2016 to February 2021.Results:During the study period, approximately 588 reports with 579 device issues and 250 patient complications were identified. Most device complications were due to stent positioning problems or stent malpositioning (n = 206; 35.6%), followed by stent migration (n = 72; 12.4%), premature deployment (n = 61; 10.5%), material integrity (n = 56; 9.6%), deployment failure (n = 47; 8.1%), and difficulty removing the stent (n = 45; 7.7%). The most reported patient adverse events were hemorrhage/bleeding (n = 81; 32.4%), perforation (n = 26; 10.4%), pain (n = 22; 8.8%), unspecified infection (n = 20; 8.0%), and death (n = 17; 6.8%).Conclusions:Findings from the MAUDE database highlight patient and device complications which endoscopists should be aware of before AXIOS stent placement.