Stent Type Research Articles

Optimal endoscopic drainage strategy for unresectable malignant hilar biliary obstruction.

Endoscopic biliary drainage strategies for managing unresectable malignant hilar biliary obstruction differ in terms of stent type, drainage area, and deployment method. However, the optimal endoscopic drainage strategy remains unclear. Uncovered self-expandable metal stents (SEMS) are the preferred type because of their higher functional success rate, longer time to recurrent biliary obstruction (RBO), and fewer cases of reintervention than plastic stents (PS). Other PS subtypes and covered SEMS, which feature a longer time to RBO than PS, can be removed during reintervention for RBO. Bilateral SEMS placement is associated with a longer time to RBO and a longer survival time than unilateral SEMS placement. Unilateral drainage is acceptable if a drainage volume of greater than 50% of the total liver volume can be achieved. In terms of deployment method, no differences were observed in clinical outcomes between side-by-side (SBS) and stent-in-stent deployment. Simultaneous SBS boasts a shorter procedure time and higher technical success rate than sequential SBS. This review of previous studies aimed to clarify the optimal endoscopic biliary drainage strategy for unresectable malignant hilar biliary obstruction.

Ureteral Stent Colonization and Urinary Tract Infection in Children Undergoing Minimally Invasive Pyeloplasty.

Minimally invasive pyeloplasty (MIP), namely, laparoscopic and robot-assisted interventions, has gained popularity in recent years. Double-J ureteral stents are frequently inserted during surgery. Foreign bodies in the urinary tract are considered as risk factor for developing urinary tract infection (UTI). This study aimed to specify the bacteria cultured from urine and stents responsible for UTI in children with indwelling ureteral stents undergoing MIP. We retrospectively reviewed medical records of 30 children (22 boys and 8 girls) who had undergone MIP between 2014 and 2017. Median age at surgery was 2.7 years (interquartile range [IQR]: 0.5-7.9). Urine cultures were obtained before surgery, before stent removal, 1 month after stent removal, and if UTI was suspected. Stents were removed 4 to 8 weeks after surgery and cultured. Patients' demographics, types of stents, and surgical details were recorded. Median stent indwelling time was 5.09 weeks (IQR: 4-6). Postoperative febrile UTI developed in 4/30 (13%) patients. Afebrile UTI occurred in another 4/30 (13%) patients. Stent cultures were positive in 19/30 (63%) patients. Stent and urinary cultures were identical in only one patient. Three of four patients with preoperative asymptomatic bacteriuria developed postoperative UTI. There was no association between UTI, gender, stent diameter, and duration of indwelling catheter. After MIP, febrile UTI and afebrile UTI occurred in about one quarter of patients. Pathogens isolated postsurgically from urinary cultures were unrelated to those colonizing the stents. Therefore, routine stent culturing is of low clinical significance. Moreover, small-caliber stents and longer indwelling periods were not risk factors for UTI. Optimizing antibiotic treatment for children with preoperative UTI may potentially prevent morbidity after surgery.

Early Stent Patency After Endovascular Therapy for Tandem or Isolated Carotid Steno-Occlusive Disease

Early Stent Patency After Endovascular Therapy for Tandem or Isolated Carotid Steno-Occlusive Disease

Usefulness of 3D T1-Turbo Spin Echo Imaging for the Evaluation of Intracranial Stent Placement.

Evaluation of intracranial stent placement by MRI suffers the problems of signal artifacts during time-of-flight MRA (TOF-MRA). Therefore, angiographic examination is required for detailed intravascular assessment of the stent placement site. Recently, 3D T1-turbo spin echo (3D-TSE) has been developed for evaluation of carotid artery stent placement. We investigated the use of the 3D-TSE imaging method for the evaluation of intracranial vascular stent placement. The subjects consisted of nine patients who underwent intracranial vascular stent placement between April 2015 and December 2019. Postoperatively, the lumens of the placed stents were measured by TOF-MRA, DSA, and 3D-TSE imaging. Analysis was performed by type of stent and placement site. The stents used were Neuroform Atlas (3 patients), LVIS (3 patients), LVIS Jr (2 patients), and Integrity (1 patient). TOF-MRA of the stent placement site showed defects in the image or poor visualization in all nine patients, whereas 3D-TSE imaging visualized the lumen at the stent indwelling site in all patients. The blood vessel diameter measured by the DSA and 3D-TSE imaging exhibited positive correlations regardless of the stent type and placement site. 3D-TSE imaging allows visualization of the lumen of the site of an intracranial vascular stent, regardless of the type of stent or the vessel. Thus, this method may be useful for evaluating the vascular lumen of a lesion.

REVIEW ON COMPLICATIONS AND ADVERSE EFFECTS OF METALLIC URINARY STENTS.

Urinary stents, be it urethral or ureteral, polymeric, metallic or biodegradable, are one of the most frequently used tools in urology and they have been used for decades in prophylactic and therapeutic setting. Although relatively low invasive, they are prone to complications and adverse effects so much that complication rates up to 100% have been described. Many reviews have focused either on specific groups of patients or particular stent types, materials or designs but so far, no comprehensive review on complications has been published. To tackle this issue, a working group was set up within ENIUS (European Network of multidisciplinary research to Improve Urinary Stents) tasked with literature search in order to screen for and systematically review published stent complications in urethra (male only) and ureters (polymeric and metallic ureteral stents in both sexes) when used in obstructed systems. In this paper, we review, catalogue and summarize complications published for metallic urethral and ureteral stents.

Effect of Bronchoscopic Spray Cryotherapy and Ultra-low Temperature on Physical Properties of Metallic and Silicone Airway Stents.

Bronchoscopic spray cryotherapy (SCT) is utilized in the field of interventional pulmonology for treating benign and malignant airway stenosis as a standard tool to maintain airway patency. Stent-related complications include tumor overgrowth, granulation tissue, and epithelialization. Thermal ablation can have a limited role in such scenarios due to the risk of airway fire and damage to the existing stent. SCT is a potential therapy using ultra-low temperatures that can allow stents to remain in place during treatment. However, there has been no study demonstrating the safety of SCT on the integrity and physical properties of tracheobronchial stents. We report the results of the first study demonstrating the safety of SCT utilized to treat stent-associated granulation or malignant airway disease. The aim of this study was to demonstrate the effects of SCT on the physical properties of airway stents in an ex vivo environment. Various types of airway stents were subjected to multiple intervals of SCT for up to 30 seconds, and then the cycle was repeated 3 times. After every cycle, we compressed the stents to 60% of their original size, and compression and expansion force data was collected immediately after, at 3-minute and 5-minute intervals, and compared with the baseline readings. There was no significant change in the association between diameter and compression/expansion force, including any derangement in returning to the original diameter or any physical damage to any of the stents even after 3 prolonged SCT sessions of 30 seconds. Our study provides the first evidence that the use of SCT in conjunction with existing silicone/metal stents is feasible and does not cause any physical damage to the stents or alters their ability to maintain the original diameter.

Tissue Stents (Bio Stents): Search For Non- Metallic Stent And Can It Be A Game Changer In Cardiovascular Interventions?

Coronary and Vascular stenosis poses great challenge in terms of cardiovascular disease burden. Evolution of metallic stents has been key in treating Coronary Artery Disease both acute and chronic and has met challenges successfully. The last 2 decades have seen substantial reform in technology, bringing second and third generations of coronary and vascular stents mainly metallic drug-eluting stents (DES). Though stent related stenosis is big challenge, DES has met relatively much success especially during initial years. DES are found to be associated with good first-year outcomes but subsequent risk of stentrelated adverse events like thrombosis, myocardial infarction, restenosis usually appear after 1 year following implantation. The pathogenesis of these late events is related to the permanent presence of the metal stent frame or polymer within coronaries. Besides intimal hyperplasia, late stent thrombosis, and noncompliance with DAPT are still major issues leading to stent failure and often the need for reintervention. As an effective alternative to metallic stents, Bioresorbable scaffolds were developed to provide drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete resorption with recovery of vascular structure and function, potentially improving very late clinical outcomes. A first-generation bioresorbable scaffold demonstrated to be no inferior to a contemporary metallic drug-eluting stents for overall 1-year patient-oriented and deviceoriented outcomes. However, increased rates of scaffold thrombosis and target vessel-related myocardial infarction were noted subsequently at 5 year follow up. Tissue/Bio Stents can present as a path breaking alternative approach to avoid intimal hyperplasia. They are characterised by presence of biodegradable struts with tissue mesh and complete absence of metal preventing ingrowth of the neointimal tissue into the lumen. Currently used stent materials include mainly metals and synthetic polymers. Their main limitation is lack of hemocompatibility, which can induce thrombosis and ultimately reocclusion, thus impairing the long-term performance of these devices. We are proposing use of biologically derived material to overcome this issue with the aim of enhancing the biocompatibility and the capability of this type of stents to support endothelialilzation. The aim of this article is to give a comprehensive overview of the manufacturing and applications of Tissue or Bio Stents as well as the different strategies followed for their development from the perspective of the material selection, fabrication approaches, and logical validation of the different concepts into animal and clinical trials.

Обструкция мочеточника и локальные стенты верхних мочевыводящих путей

Currently, various types of stents are widely used in urological practice. One of the indications is the presence of upper urinary tract strictures. The factors leading to the development of strictures can be endogenous and exogenous, iatrogenic and non-iatrogenic, benign and malignant. After open, laparoscopic and X-ray-endoscopic procedures a double-J stent is usually placed or, less often, nephrostomy tube. It should be noted that both methods have certain side effects and may affect the patient's quality of life. To reduce the stent-related symptoms and increase their tolerability, various modifications of ureteral stents have been developed. In this article, we analyze the publications devoted to the most commonly used segmental stents without renal and bladder coils, such as Memokath, Uventa, Allium, Memotherm and nitinol stents manufactured by MIT LLC.

Risk factors for in-stent restenosis in maintenance hemodialysis patients with central venous occlusive disease and biomechanical assessment of stents.

To investigate the risk factors and biomechanical mechanisms of in-stent restenosis (ISR) in central venous occlusive disease (CVOD). This retrospective study consecutively included 77 maintenance hemodialysis (MHD) patients with CVOD who received the first percutaneous transluminal angioplasty with stenting (PTS) due to symptomatic CVOD in a tertiary hospital. The mean age was 59.7 ± 14.0 years, and 51.9% of patients were male. The clinical characteristics, occurrence of ISR and patency rates were recorded. Finite element method was applied to assess the biomechanical properties of stents. Among 77 patients with a mean CVS score of 8.0 ± 2.8, 20.8%, 62.3%, and 16.9% of patients had the main vein of CVOD in the subclavian vein, brachiocephalic vein, and superior vena cava, respectively. A total of 72 (93.5%) patients received successful PTS treatment, for which the stents implanted were mainly Fluency covered stent (48.6%) and SMART bare stent (31.9%). During 15 (10-24)-months of follow-up, ISR occurred in 36.1% of the 72 patients. The primary and assisted primary patency rates at 6, 12, and 18 months were 78%, 56%, 42% and 95%, 90%, 87%, respectively. A prolonged dialysis vintage was an independent risk factor for ISR, yet the stent type or the main vein location was not correlated with ISR. Among three laser-engraving stents, the SMART stent was the best in terms of flexibility, stress, and strain on stents but worst in stress or strain on vessels. The Luminexx stent was the best in radial force and worst in stress or strain on stents. The Vici stent was the best in stress and strain on vessels and worst in radial force and flexibility. An unsatisfactory comprehensive biomechanical performance from configurations rooted in existing stents may account for the high incidence of ISR in CVOD.

Dual-layer carotid stenting for symptomatic carotid web: Results from the Caroweb study

Background & purposeCarotid Web (CaW) is a growingly recognized cause of ischemic stroke, associated with a high recurrence risk. Several therapeutic strategies have been proposed as a tertiary prevention including carotid stenting, endarterectomy and antithrombotic medications. Among these, carotid stenting with dual-layer stent may be promising to adequately cover the focal arterial dysplasia. Our aim was to investigate the safety and efficacy of the Casper stent in the treatment of symptomatic CaW. MethodsWe conducted a retrospective analysis of consecutive patients presenting with a symptomatic CaW and included in the ongoing prospective observational multicenter CAROWEB registry. The study period was January 2015 to December 2021. Inclusion criteria were CaW treated with dual-layer Casper stent. Patients treated with other types of carotid stent, endarterectomy or antithrombotic medication were excluded. Clinical and radiological initial data and outcomes were recorded. Resultstwenty-seven patients (with 28 caw) were included. median age was 52 (iqr: 46–68). median delay between index cerebrovascular event and cervical stenting was 9 days (IQR: 6–101). In all cases, the cervical carotid stenting was successfully performed. No major perioperative complication was recorded. No recurrent stroke or transient ischemic attack was observed during a median follow-up time of 272 days (IQR: 114–635). Long-term imaging follow-up was available in 25/28 (89.3%) stented CaW with a median imaging follow-up of 183 days (IQR: 107–676; range: 90–1542). No in-stent occlusion or stenosis was detected. ConclusionIn this study, carotid stenting with dual-layer Casper stent in the treatment of symptomatic CaW was effective regarding stroke recurrence prevention and safe, without procedural nor delayed detected adverse event. However, the optimal therapeutic approach of symptomatic CaW still needs to be explored through randomized trials.

Simplified modeling of implanted medical devices with metallic filamentary closed loops exposed to low or medium frequency magnetic fields

Background and objectivesElectric currents are induced in implanted medical devices with metallic filamentary closed loops (e.g., fixation grids, stents) when exposed to time varying magnetic fields, as those generated during certain diagnostic and therapeutic biomedical treatments. A simplified methodology to efficiently compute these currents, to estimate the altered electromagnetic field distribution in the biological tissues and to assess the consequent biological effects is proposed for low or medium frequency fields. MethodsThe proposed methodology is based on decoupling the handling of the filamentary wire and the anatomical body. To do this, a circuital solution is adopted to study the metallic filamentary implant and this solution is inserted in the electromagnetic field solution involving the biological tissues. The Joule losses computed in the implant are then used as a forcing term for the thermal problem defined by the bioheat Pennes’ equation. The methodology is validated against a model problem, where a reference solution is available. ResultsThe proposed simplified methodology is proved to be in good agreement with solutions provided by alternative approaches. In particular, errors in the amplitude of the currents induced in the wires result to be always lower than 3%. After the validation, the methodology is applied to check the interactions between the magnetic field generated by different biomedical devices and a skull grid, which represents a complex filamentary wire implant. ConclusionsThe proposed simplified methodology, suitable to be applied to closed loop wires in the low to intermediate frequency range, is found to be sufficiently accurate and easy to apply in realistic exposure scenarios. This modeling tool allows analyzing different types of small implants, from coronary and biliary duct stents to orthopedic grids, under a variety of exposure scenarios.

Update on Clinical Management with Neurovascular Stents.

Endovascular stenting has continued to evolve given the new trials. Several new stents have recently been developed to address specific purposes. In this focused review, we discuss the concepts of neurointerventional stents and address the clinical implications. Furthermore, each type of stent is discussed with supporting evidence for clinical utility. In the final component, we argue for continued development and utilization.

HPB P07 A propensity matched retrospective study of metal vs plastic stents in the preoperative biliary drainage of patients with resectable perihilar cholangiocarcinoma

Abstract Background Preoperative biliary drainage is required in the majority of patients with resectable perihilar cholangiocarcinoma (pCCA). Most centres use plastic stents rather than uncovered self-expanding metal stents (uSEMS) because of the potential difficulties associated in removing uSEMS. In the palliative setting, however, uSEMS are associated with superior patency and even improved survival. The aim of this study is to compare the utility of uSEMS versus plastic stents in the pre-operative drainage of patients with resectable pCCA. Methods In this retrospective, multicentre, international cohort study, all consecutive patients with a high suspicion of resectable pCCA who underwent an initial endoscopic biliary drainage with uSEMS or plastic stent between 2010–2020 were included. Analyses were stratified by groups according to initial stent type. The primary outcome was stent failure, which was a composite endpoint of cholangitis and/or re-intervention due to biliary complications or inadequate biliary drainage. Propensity score matching (1:1) was performed to adjust for age, gender, primary sclerosing cholangitis, Bismuth classification, WHO performance status and ASA classification. Results A total of 474 patients with successful initial stent placement were included. Of these patients 61 received uSEMS and 413 plastic stents. Matching resulted in two groups of 59 patients. Stent failure occurred significantly less in the uncovered uSEMS group (31% vs 64%, P<0.001) and resulted in a significant reduction in the number of repeat ERCP procedures (14% vs 54%, P<0.001). Despite this the number of patients eventually required percutaneous transhepatic biliary drainage was similar (9% vs 7%, P=1). uSEMS placement was also associated with a reduction in episodes of cholangitis (15% vs 31%, P=0.012), although other ERCP and stent related complications did not differ. The number of patients ultimately undergoing surgical resection was not significantly different (81% vs 90%, P=0.19) between groups with uSEMS removal during surgery successful in all patients. The median overall survival after initial stent placement was 482 days [95% CI, 338–787] in the uSEMS group and 429 [95% CI, 263–881] in the plastic stent group (log-rank P=0.81). Survival after surgical resection was similar and post-operative outcomes also comparable: R1 resections (58% vs 59%, P=0.569), complications according to Clavien-Dindo (P=0.227), and hepatico-jejunostomy associated complications (leak: 4% vs 14%, P=0.393, stricture: 15% vs 21%, P=0.822). Conclusions Stent failure occurred significantly less often in uSEMS group resulting in fewer drainage procedures and reduced episodes of cholangitis. Removal of uSEMS during surgery was feasible and surgical outcomes were comparable. Although preoperative biliary drainage by uSEMS shows promising results further study is warranted and multicentre randomized controlled trials with a clear treatment strategy should be performed.

Carotid Artery Stenting for Patients With Carotid Stenosis and Contralateral Carotid Artery Occlusion: A 12-Year Experience

Carotid artery stenting (CAS) has emerged as a potential alternative for treating patients with extracranial cerebrovascular diseases. Contralateral carotid artery occlusion (CCO) occurs in approximately 2.3% to 25% of patients with carotid artery stenosis. However, the association of a CCO with long-term outcomes after CAS remains unclear. Here, we aimed to evaluate the perioperative and long-term recovery and safety of patients with CCO after receiving CAS. We retrospectively collected the data of patients with CCO treated with CAS between 2010 and 2021. The primary endpoint was a nonfatal major stroke. The secondary endpoints included cerebral hemorrhage, nonfatal myocardial infarction (MI), restenosis, acute renal insufficiency, stent-related complications, and death. Long-term outcomes were analyzed by Kaplan-Meier survival analysis using the following variables: symptomatic carotid stenosis, age, stent type, collateral flow status, and post-dilation. Seventy-one consecutive patients with CCO who underwent CAS were included in the study. Of these, 61 patients (86%) were followed up for 9-134 months, with an average of 63.3 ± 30.4 months. In the perioperative period, 2 patients (2.8%) experienced stroke, and 1 patient (1.4%) died due to cerebral hemorrhage combined with cerebral hernia. During follow-up, 2 patients (3.3%) developed stroke at 4 and 6 months each after CAS, and 6 patients (9.8%) died (2 patients died due to MI, and 4 patients died due to either severe liver failure, car accident, cervical fracture, or unknown cause. Kaplan-Meier survival analysis showed that symptomatic carotid stenosis, age, stent type, and post-dilation were not associated with long-term stroke (P＜0.05). The inadequate collateral flow group showed a higher stroke rate than the control group (P = 0.009). CAS is a safe and effective therapy for patients with CCO. Inadequate collateral flow is associated with a higher long-term rate of stroke. Our findings revealed that symptomatic carotid stenosis, age, stent type, and post-dilation had no significant effect on outcome events after CAS.

Ultrashort Echo Time Magnetic Resonance Angiography as an Alternative Tool to Digital Subtraction Angiography in the Follow-up of Stent-Assisted Coil Embolization Outcomes.

Follow-up of aneurysms treated with stent-assisted coil embolization has been performed using digital subtraction angiography (DSA) because in time-of-flight magnetic resonance angiography, metal artifacts from the stent often affect visualization. To confirm whether ultrashort echo time (TE) MRA may be an alternative for DSA during follow-up. Patients with unruptured aneurysms initially treated with stent-assisted coil embolization between April 2019 and March 2021 were enrolled. After 3 months of treatment, follow-up DSA and ultrashort TE MRA were performed. All images were independently reviewed by neurosurgeons to evaluate in-stent flow and rated from 1 (not visible) to 4 (excellent). Aneurysmal embolization status was assessed as complete obliteration, residual neck, or residual aneurysm. Ultrashort TE MRA findings were classified as evaluative or nonevaluative state based on the presence of metal artifacts. We investigated the types of aneurysms that were evaluative and the agreement between ultrashort TE and DSA. Overall, 89 aneurysms were examined, of which 74% (n = 66) were classified as evaluative on ultrashort TE. Significant differences were observed in size and stent type. Evaluative cases had an aneurysm size of <7 mm ( P = .0007) and a higher rate of Neuroform Atlas ( P = .0006). The rate of agreement between ultrashort TE with evaluative state and DSA was 95%. Ultrashort TE MRA could evaluate an embolization status treated with stenting, and the findings are in excellent agreement with those of DSA. Aneurysms measuring <7 mm and treated with Neuroform Atlas are evaluative on ultrashort TE, and DSA might not be necessary.

Endoscopic treatment for duodenal perforation due to biliary stent dislocation: A case report and brief review of the literature

Duodenal wall perforation by a dislocated biliary stent placed for biliary structure is rare but can be life-threatening. There are few reports on the management of stent-related duodenal perforation. Three cases included in this study had undergone endoscopic retrograde cholangiopancreatography with placement of a plastic stent for biliary stricture. Two cases had symptoms (fever or abdominal pain), while other case showed no symptom after biliary stent placement. Dislocation of plastic stents was revealed on computed tomography or endoscopic images. Two patients were diagnosed with duodenal perforation due to distal migration of long stents with a straight shape on the distal side. One patient was diagnosed with fistula formation between the intrahepatic bile duct and duodenum due to perforation of a pigtail stent. All cases could successfully be managed endoscopically with closure by hemoclips or stent replacement. All 3 cases were improved after endoscopic treatment without any subsequent intervention. Longer stents with a straight distal side are associated with a higher risk of duodenal perforation. Endoscopic management is appropriate as a first-line approach for a clinically stable patient. At the time of stent placement, we should pay attention to the length and type of stent.

Ionized and non-ionized radiation effects on coronary stent implantation

The purpose of this study is to examine the clinical radiation effects on patients with various stents. Several previous researches focused on the mechanical and physical features of the stents, but there have been few studies that focus on the interaction with radiological and clinical radiation. For stent material analysis, the ANSYS package program was employed. These materials and models are often built in three dimensions for three different types of stents made of three various materials. Estimates of blood pressure and thermal radiation were explored, as were the effects of non-ionizing radiation. Furthermore, the radiation attenuation characteristics of stent samples are investigated. The mass attenuation coefficient values are computed using MATLAB code over a large energy range of 0.015–15 MeV, and the findings are validated using theoretical WinXCom results. To determine the gamma-ray attenuation performances of the studied stent samples, variables such as the mass attenuation coefficient (MAC), half-value layer (HVL), tenth-value layer (TVL), mean free path (MFP), effective atomic number (Zeff), exposure build-up factor (EBF), and energy absorption build-up factor (EABF) are computed. Effective removal cross-sections (ΣR) of stent samples were acquired to determine the capacity of stent samples to stop fast neutrons. Finally, the ability of stent samples to stop charged alpha and proton particles was evaluated utilizing mass stopping power and projected range parameters. The discovery demonstrates that S3 has the best attenuation as well as the best proton, alpha, and gamma radiation attenuation capability.

Surgical Method for Glottic Web and Vocal Fold Adhesion

Laryngeal web most frequently occurs due to acquired rather than congenital factors. It can cause dysphonia and airway disorder depending on the extent of the area or thickness of the web. The prevention of relapse after web resection is the most important aspect of surgery for laryngeal web. A local mucosal flap can be developed using the superior and inferior surface of the web. This flap can cover at least one side of the wound on the vocal fold after web resection, and consequently leads to primary healing. The other technique for preventing web relapse is to place a stent (also called a “keel”) at the anterior commissure after removing the web. A slim silicone tube can be used as a stent to prevent web relapse. A membrane like plate can also be adopted. The round-shaped silicone tube has an advantage in softness for the vocal fold in comparison to a flat-shaped plate. One of the disadvantages of the silicone tube is that it cannot cover the wound that develops after the resection of a broad web affecting the posterior membranous vocal fold. To resolve this problem, we developed a new type of silicone stent that includes both a tube and a plate component. An appropriate surgical method and stent should be chosen based on the condition of the web.

Drug Eluting Versus Covered Stent for Femoropopliteal Artery Lesions: Results of the ULTIMATE Study

Stent grafts (SG) and drug eluting stents (DES) have emerged to combat intimal hyperplasia. It remains unclear which type of stent yields superior outcomes in femoropopliteal (FP) arterial lesions. This study compared the clinical data between the VIABAHN SG and the Eluvia DES two years after endovascular treatment.

Clinical study on 2 types of intrauterine stents with different thickness and hardness in the treatment of moderate-to-severe intrauterine adhesions.

Although hysteroscopic adhesiolysis (HA) is the main treatment for intrauterine adhesion (IUA), postoperative management of IUA remains challenging because there is no consensus on how to mitigate the high rate of postoperative adhesions reformation. This study aims to compare the effectiveness and safety of 2 types of intrauterine stents with different thickness and hardness in treating moderate-to-severe IUA. A retrospective clinical study was conducted in the Third Xiangya Hospital of Central South University from November 2020 to July 2021. A total of 191 patients with moderate-to-severe IUA who received surgical treatment and placed intrauterine stents after HA to prevent recurrence of postoperative adhesions were included. According to the hardness and thickness of the intrauterine stents, the participants were divided into a case group (placed the novel thin intrauterine stent, n=62) and a control group (placed the conventional stent, n=129). After 2-3 menstrual cycles, a second-look hysteroscopy was performed, and the intrauterine stents were removed. The postoperative efficacy [the reduction of American Fertility Society (AFS) scores, the adhesions reformation rate, the changes in menstrual pattern, and the pregnancy rate during the follow-up], safety (the adverse events), and applicability (the difficulty of stent removal) were compared between the 2 groups. No significant differences in preoperative clinical characteristics were observed between the 2 groups (all P>0.05). The menstrual volume of all patients was increased after the treatment. The reduction of AFS scores and the menstruation recovery rate were not significantly different between the 2 groups (P=0.519 and P=0.272, respectively). Notably, there was no case of displacement in the case group, while the displacement rate of the control group was 2.3% (P=0.552). Moreover, there was no significant difference in abdominal pain or postoperative abnormal vaginal bleeding between the 2 groups (P=0.823 and P=0.851, respectively). However, the difficulty rate of removing the thinner stents was significantly lower than that of removing the traditional stent (21.0% vs 38.8%, P=0.014). During the follow-up for half a year of the postoperative period, the pregnancy rate did not differ significantly in the case and control groups (45.0% vs 34.6%, P=0.173). The novel intrauterine stent shows noninferior efficacy and had a good safety profile compared with conventional stents in treating moderate-to-severe IUA. Importantly, it was more convenient to be removed without increasing the rate of displacement and detachment. Therefore, it could reduce the amount of damage to the endometrium and has higher applicability than conventional stents.