Flow-diverting Stents Research Articles

Immediate flow-diversion characteristics of a novel primarily bioresorbable flow-diverting stent.

Flow-diverting stents with a resorbable component have significant theoretical benefits over full metal stents, although currently there are none in clinical use. In this study, the authors sought to determine the immediate flow-diversion characteristics of a novel primarily bioresorbable flow-diverting stent. Bioresorbable stents were deployed into glass tube models to determine porosity and pore density. In vitro flow diversion behavior was evaluated using high frame rate angiography under pulsatile flow conditions in a patient-specific silicone aneurysm model treated with the resorbable stent as well as the Surpass Evolve stent. In vivo flow diversion was characterized by deployment into 20 rabbit saccular aneurysm models, and grading was based on the O'Kelly-Marotta scale and the 4F-flow diversion predictive score. Porosities and pore densities of the bioresorbable stent were in the flow-diverting range for all target vessel diameters. Quantified results of immediate angiography after placement of the bioresorbable stent into a silicone aneurysm model demonstrated greater flow diversion compared to the Evolve stent. Bioresorbable stent placement in saccular aneurysm models resulted in an immediate O'Kelly-Marotta grade of A3 or better and a 4F-flow diversion predictive score of 4 or better in all cases. The bioresorbable stent has immediate flow-diversion characteristics that are comparable to commercially available metal stents. Longer-term studies are underway to determine the ability of the resorbable fibers to act as a neointimal scaffold and result in long-term aneurysm occlusion.

Endovascular reconstruction with flow diverting stent as a treatment for recurrent internal carotid artery aneurysm. A case report

Recurrence of cerebral aneurysms after surgical treatment is an urgent medical and social problem, being a possible cause and a significant risk factor for intracranial hemorrhage, despite the primary total embolisation of the aneurysm. Timely risk assessment, diagnosis and personalized approach in the treatment of recurrent cerebral aneurysm can help improve the treatment outcomes of these patients.Purpose: to describe a case of a personalized approach in endovascular treatment of recurrent aneurysm of the ophthalmic segment of the internal carotid artery after occlusion with detachable coils.Assessment of the stability of aneurysm mbolisation in the long-term period after endovascular intervention on a cerebral aneurysm is an integral part of the treatment process in this type of cerebrovascular pathology. A personalized approach to the treatment of cerebral aneurysms, both primary and with signs of recurrence, makes it possible to improve the immediate and long-term results of treatment of patients with this type of cerebrovascular pathology. In some cases, one of the methods for solving this problem is the use of flow-diverting stents.

First case of successful usage of a low-profile flow-diverting stent for treatment of intracranial infectious aneurysm in patient with a mechanical heart valve. Clinical case and literature review

Infectious aneurysms (IA) are cerebral aneurysms that are formed due to the infectious inflammation of the arterial wall. They are a rather rare pathology and in most cases prove to be a complication of infectious (bacterial) endocarditis of the left heart chambers. Timely diagnosis of IA in the pre-hemorrhagic period is problematic due to the variability of the clinical picture of IA, frequent blurred or low-symptomatic clinical course, the possibility of IA formation in the remote period after septic embolism, even despite the background of antibiotic therapy. The presented clinical case illustrates the first successful use of a low-profile flow-diverting stent for the treatment of a young patient with a mechanical heart valve and an infectious aneurysm of the left middle cerebral artery, developed at the site of septic embolism in the acute period of septic bacterial endocarditis accompanied by ischemic stroke. This observation demonstrates the effectiveness of the chosen method of treatment, peculiarities of adequate preoperative preparation, possible postoperative complications and detailed correction of anticoagulant and antiplatelet therapy.

Stent-alone treatment of unruptured vertebral artery fusiform aneurysms: A comparison of flow diverter and conventional stents.

Treatment of vertebral artery fusiform aneurysms (VAFAs) is complex and controversial. This study aimed to compare the safety and efficacy between flow diverter and conventional stents in patients with VAFAs undergoing endovascular stent-alone treatment (SAT). Thirty-six patients with 36 VAFAs who underwent SAT between January 2014 and December 2018 were retrospectively analyzed. Patient and aneurysm characteristics, procedural details, complications, and angiographic and clinical outcomes were compared between flow diverter stent patients (n = 22) and conventional stent patients (n = 14). More branches covered with stent were found in the conventional stent group (88.9 vs. 33.3%; p = 0.008). The number of stents placed was significantly higher in the conventional stent group (1.57 ± 0.76 vs. 1.09 ± 0.29; p = 0.016). The proportion of patients with significant or moderate stasis within the aneurysm immediately after stent placement was higher in the flow diverter stent group (95.5 vs. 57.1%; p = 0.004). The proportion of patients with complete obliteration or only a residual neck on follow-up angiography was significantly higher in the flow diverter stent group (86.3 vs 50.0%; p = 0.047). However, the incidence of parent artery stenosis or occlusion was also higher in the flow diverter stent group (27.3% vs. zero; p = 0.032). The rate of complications did not significantly differ between the groups. SAT was safe and effective in patients with VAFAs. Flow diverter stents are associated with a significantly better complete occlusion rate than conventional stents; however, they are also associated with an increased risk of parent artery stenosis.

Endovascular treatment of challenging aneurysms with FRED Jr flow diverter stents: a single-center experience.

To analyze clinical safety and efficacy of flow re-direction endoluminal device (FRED) Jr flow diverter for treatment of unruptured, ruptured, or recanalyzed aneurysms. Between October 2019 and February 2022, 25 patients with 31 aneurysms treated with FRED Jr were included in the study. Clinical and radiological records, procedural details, and follow-up outcomes were retrospectively evaluated. Eighteen (72%) patients were female. Median age was 48.8 (age range 9-85). Mean follow-up was 21months (6-28months). Location of the aneurysms were as follows; 13 in middle cerebral artery (MCA), 7 in anterior cerebral artery (ACA), 4 in posterior cerebral artery (PCA), 3 in true posterior communicating artery (PCom), 2 in anterior communicating artery (ACom), 1 in superior cerebellar artery (SCA), 1 in true ophthalmic artery. Five patients (20%) presented with acute subarachnoid hemorrhage (aSAH). In all procedures, FRED Jr was successfully deployed. Three true Pcom aneurysms and a true ophthalmic aneurysm were treated with FRED Jr. Three patients with two adjacent aneurysms were treated with a single FRED Jr. In two (8%) patients in-stent thrombosis occurred intraoperatively, they were treated with iv tirofiban and thrombectomy without any sequelae. Post-discharge 2weeks later, intraparenchymal hemorrhage occurred in a patient. He was treated with surgical drainage, the clinical course was modified Rankin score (mRS) 2. Digital subtraction angiography (DSA) was performed on 16 (64%) patients with 21 (67%) aneurysms. Near complete-complete occlusion (O'Kelly-Morata grading scale (OKM C-D) was documented in 15/16 (93.7%) patients, 20/21 (95.2%) aneurysms. In nine (36%) patients, no residual filling was observed in the magnetic resonance angiography (MRA). Good clinical outcome (mRS 0-1) was achieved in 24/25 (96%) of patients. Endovascular treatment of small cerebral aneurysms with FRED Jr is safe and effective even in complex and challenging morphologies allowing high rates of aneurysm occlusion with low periprocedural complications. Our cohort, consisting of a rate 20% acute ruptured aneurysms, is the major additive data to the published literature.

Treatment of cerebral aneurysms with the FRED Jr flow-diverting stent: A case series and meta-analysis

BackgroundWith the development of the Flow Re-Direction Endoluminal Device Junior (FRED Jr), treatment of distal aneurysms and/or aneurysms with small parent vessels has become a viable option. ObjectivesTo assess the efficacy and safety of FRED Jr in the treatment of distal aneurysms with small parent vessels. MethodsThis is a single center retrospective study and meta-analysis of patients treated with FRED Jr for intracranial aneurysms. The primary outcome was complete aneurysm occlusion at final follow-up. Secondary outcomes included stroke rates, mortality rates, need for retreatment and clinical outcomes. ResultsThere were a total of 7 patients with 7 aneurysms treated with FRED Jr. Mean aneurysm neck, width, height, and parent artery diameter were 2.6 ± 0.8 mm, 3.1 ± 0.9 mm, 2.5 ± 1.0 mm, and 1.8 ± 0.6 mm respectively. The complete occlusion rate was 57.1 % at 6 months, and favorable outcome (mRS 0–2) was observed in all patients in follow-up. Stroke complication occurred in none of the patients. Seven studies from 1360 articles were identified for inclusion in the meta-analysis, comprising 227 patients with 244 aneurysms treated with FRED Jr. Mean aneurysm height, width, neck and parent artery diameter were 6.9 ± 3.3 mm (pooled=5.6 [<0.1–11.47] mm), 6.6 ± 2.2 mm (pooled=6.6 [4.2–9.1] mm), 4.4 ± 1.4 mm (pooled=4.1 [3.3 −4.9] mm), and 2.0 ± 0.2 mm (pooled=2.1 [1.7–2.5]), respectively. At final follow-up, the pooled complete occlusion and complication rates were 69.9 % and 0 %, respectively. ConclusionFRED Jr demonstrated moderate efficacy and good safety in the treatment of distal aneurysms with small parent vessels at mid-term follow-up.

Tortuosity of parent artery predicts in-stent stenosis after pipeline flow-diverter stenting for internal carotid artery aneurysms.

Background and purposeThe relationship between the tortuosity of the parent artery and treatment outcomes is not well established. We investigate the association between parent artery tortuosity and flow diverter (FD) treatment outcomes in patients with internal carotid artery aneurysms in this study.MethodsA retrospective review study was conducted to identify all patients with internal carotid artery aneurysms who were implanted with Pipeline embolization device (PED) between 2016 and 2020. The relationship between parent artery tortuosity and aneurysm complete occlusion (CO) and in-stent stenosis (ISS) was analyzed. The mathematical parameters “Curvature”, “torsion”, and “DM” extracted from the parent artery were utilized to quantify the parent artery tortuosity. A vascular narrowing of greater than 25% was categorized as ISS. Logistic regression analysis was used to identify significant independent predictors. Furthermore, we compared the performance of four machine learning algorithms and Logistic Regression model in predicting ISS.ResultsThis research included 62 patients who with internal carotid artery aneurysms. In 49 (79%) cases, follow-up angiography (mean follow-up duration 11.7 ±7.3 months) revealed CO of the aneurysm. ISS was detected in 22 (35.5%) cases. According to univariate analysis, parent artery tortuosity and other variables were not associated with CO (p > 0.1). Maximum curvature (OR = 1.084; 95% CI, 1.008–1.165; p = 0.03) and DM (OR = 0.01; 95% CI, 0–0.488; p = 0.02) exhibited strong independent associations with ISS in multivariate analysis. The SVM model is superior to the conventional Logistic Regression model and the other models in predicting ISS.ConclusionsThe tortuosity of the parent artery may affect the treatment outcome of FD stenting. We found that parent artery tortuosity was associated with ISS, but not with aneurysm complete occlusion following PED stenting for internal carotid artery aneurysms in this study. Parent arteries with higher maximum curvature and lower DM were more likely to develop ISS.

Retreatment with a flow diverter for recurrent blood blister-like aneurysms after embolization: A single-center case series.

Background and purposeTreatment of blood blister-like aneurysms (BBAs) has been a significant challenge mainly due to their high recurrence rate even after stent-assisted coiling (SAC) embolization. This study aims to evaluate the safety and efficacy of treating recurrent BBAs after SAC with a flow diverter (FD).MethodsA retrospective series of patients with recurrent BBAs who underwent the retreatment with the FD from June 2018 to December 2021 was included to analyze perioperative safety and immediate postoperative and follow-up outcomes.ResultsThe study enrolled 13 patients with recurrent BBAs previously treated with SAC. Within previous stents, an FD was deployed for retreatment, including eight Tubridge FDs and five PEDs. The time interval between initial treatment and FD implantation was 14–90 days. A total of 11 cases were treated with a single FD alone; two cases were treated with further endovascular coiling embolization, followed by FD implantation. The angiographic follow-up (6–12 months) was available in 12 patients, and all 12 recurrent BBAs were completely occluded. No perioperative complication was detected, and no rebleeding was found during the clinical follow-up (6–36 months).ConclusionThe use of the FD to manage recurrent BBAs after SAC is technically feasible, safe, and effective. The key to the success of the procedure is to ensure that the FD stent is fully open and has good apposition with the previously implanted stent.

Flow diversion for cerebral aneurysms.

The treatment of cerebral aneurysms includes open microsurgical options (e.g., clipping, trapping/bypass) and evolving endovascular techniques. Following the landmark trials that propelled endovascular treatment to the forefront, flow diversion has shown high aneurysm cure rates with minimal complications. Flow diversion stents are placed in the parent vessel, redirecting blood flow from the aneurysm, promoting reendothelization across the neck, and resulting in complete occlusion of the aneurysm. As a result, flow diversion has become increasingly used as the primary treatment for unruptured aneurysms; however, its applications are being pushed to new frontiers. Here, the authors present three cases showcasing the treatment of intracranial aneurysms with flow diversion. The video can be found here: https://stream.cadmore.media/r10.3171/2022.7.FOCVID2253.

Treatment of an acutely ruptured complex fusiform middle cerebral artery aneurysm with flow diverting stenting and adjunctive coil embolization.

This technical video demonstrates the treatment of an acutely ruptured, large, complex left fusiform middle cerebral artery (MCA) aneurysm with endovascular flow diversion with adjunctive coiling in a 27-year-old female. Two telescoping flow-diverting stents (Pipeline Flex) were placed, with partial coiling of a saccular portion of the aneurysm. Technical challenges, alternative treatment, intraoperative and postoperative antiplatelet management, vasospasm treatment, and clinical and radiographic follow-up are described. The video can be found here: https://stream.cadmore.media/r10.3171/2022.7.FOCVID2249.

AN UNUSUAL PRESENTATION OF A PULSATILE NECK MASS

AN UNUSUAL PRESENTATION OF A PULSATILE NECK MASS

Treatment of a ruptured blister aneurysm of the left internal carotid artery with telescoping Pipeline Flex embolization devices with Shield Technology.

Ruptured blister aneurysms have significant rates of morbidity and mortality, but evidence of positive results with use of flow-diverting stents such as the Pipeline embolization device (PED) is growing. The authors describe the staged endovascular treatment of a ruptured left internal carotid artery blister aneurysm in a patient with a Hunt and Hess grade IV subarachnoid hemorrhage. PED placement was done via the common femoral artery using a triaxial delivery system. The telescoping stent technique performed over 48-72 hours achieved sufficient coverage of the aneurysm neck while limiting treatment time during the acute presentation and allowing interim dual antiplatelet treatment. A staged approach allows the targeting of a second PED placement in patients whose aneurysm continues to fill on the first follow-up angiogram. The authors have not experienced increased thromboembolic complications with this approach. Complete occlusion was achieved by postbleed day 8. The video can be found here: https://stream.cadmore.media/r10.3171/2022.7.FOCVID2264.

How precise is PreSize Neurovascular? Accuracy evaluation of flow diverter deployed-length prediction.

The use of flow-diverting stents has been increasingly important in intracranial aneurysm treatment. However, accurate sizing and landing zone prediction remain challenging. Inaccurate sizing can lead to suboptimal deployment, device waste, and complications. This study presents stent deployment length predictions offered in medical software (PreSize Neurovascular) that provides physicians with real-time planning support, allowing them to preoperatively "test" different devices in the patient's anatomy in a safe virtual environment. This study reports the software evaluation methodology and accuracy results when applied to real-world data from a wide range of cases and sources as a necessary step in demonstrating its reliability, prior to impact assessment in prospective clinical practice. Imaging data from 138 consecutive stent cases using the Pipeline embolization device were collected from 5 interventional radiology centers in the United Kingdom and retrospectively analyzed. Prediction accuracy was calculated as the degree of agreement between stent deployed length measured intraoperatively and simulated in the software. The software predicted the deployed stent length with a mean accuracy of 95.61% (95% confidence interval [CI] 94.87%-96.35%), the highest reported accuracy in clinical stent simulations to date. By discounting 4 outlier cases, in which events such as interactions with coils and severe push/pull maneuvers impacted deployed length to an extent the software was not able to simulate or predict, the mean accuracy further increases to 96.13% (95% CI 95.58%-96.69%). A wide discrepancy was observed between labeled and measured deployed stent length, in some cases by more than double, with no demonstrable correlation between device dimensions and deployment elongation. These findings illustrate the complexity of stent behavior and need for simulation-assisted sizing for optimal surgical planning. The software predicts the deployed stent length with excellent accuracy and could provide physicians with real-time accurate device selection support.

Poly(2-methoxyethyl acrylate) (PMEA) improves the thromboresistance of FRED flow diverters: a thrombogenic evaluation of flow diverters with human blood under flow conditions.

Surface modification of flow-diverting stents has been explored to reduce thrombus-related complications that may arise under clinical use. This study investigated the thromboresistant properties of the flow redirection endoluminal device (FRED) X, a flow diverter treated with a copolymer of poly(2-methoxyethyl acrylate) (PMEA; X Technology). The performance of FRED, FRED X, and Pipeline Flex with Shield Technology (sPED) was evaluated in an in vitro blood loop model. Blood activation level was assessed by the concentration of thrombin-antithrombin complex (TAT), β-thromboglobulin (β-TG), and platelet count, and qualitatively by scanning electron microscopy (SEM). Cellular adhesion characteristics were measured using human aortic endothelial cells that were seeded on flat sheets mimicking the surface of FRED, FRED X, and sPED, and evaluated with fluorescence microscopy. Statistical comparisons were conducted using one-way analysis of variance (ANOVA) with Tukey post hoc tests. FRED X, sPED, and control blood loops showed significantly reduced blood activation levels (TAT and β-TG) compared with FRED (p<0.01). Consequently, FRED showed a significant decrease in platelet count compared with FRED X, sPED, and control loops (p<0.01). SEM imaging showed the lowest accumulation of blood cell-like deposits on FRED X compared with sPED and FRED, while FRED had the highest accumulation. Endothelial cells adhered and were widely spread on X Technology-treated sheets, while minimal cell adhesion was observed on phosphorylcholine-treated sheets. The X Technology surface modification of FRED X demonstrated superior thromboresistant properties over untreated FRED while maintaining comparable cellular adhesion. Taken together, these properties may help mitigate material-related thromboembolic complications.

Treatment of giant intracranial aneurysms using the Pipeline flow-diverting stent: Long-term results from the International Retrospective Study of the Pipeline Embolization Device (IntrePED) study.

Traditional endovascular treatments of giant intracranial aneurysms are associated with high rates of complications and retreatment. Our objective was to examine the safety and long-term efficacy of the Pipeline Embolization Device for treatment of these aneurysms. This retrospective study using the IntrePED database included all patients with giant intracranial aneurysms treated with the Pipeline device between July 2008 and February 2013. Efficacy outcomes were stratified by using the Raymond-Roy Occlusion Classification. Predefined safety outcomes included spontaneous rupture of the target aneurysm; ipsilateral intracranial hemorrhage; ischemic stroke; parent artery stenosis; and sustained cranial neuropathy. Sixty-six embolizations were performed to treat 63 giant intracranial aneurysms (including 2 ruptured): 49 (77.8%) in the anterior and 14 (22.2%) in the posterior circulation. The median follow-up was 22.4 (0.1-60.5) months. Class I angiographic occlusion was achieved in 72.0% (36/50). The neurological morbidity/mortality rate was 23.8% (15/63), with higher rates in the posterior circulation than in the anterior circulation (22.4% vs. 28.6%). Among seven deaths, five had neurological causes. The procedure-related neurological morbidity and mortality rates were 22.7% (15/66) and 7.6% (5/66), respectively. The spontaneous rupture rate was 4.5% (3/66). Two spontaneous ruptures (1 death), 4/4 postprocedural intracranial hemorrhages, and 6/9 ischemic events occurred within 30 days. In-stent stenosis and new-onset cranial neuropathy were not observed during the angiographic follow-up period. Although procedure-related neurological morbidity/mortality rates were not insignificant, this study confirms the feasibility and long-term efficacy of the Pipeline Embolization Device to treat giant intracranial aneurysms.

Endovascular treatment of aneurysms of the paraophthalmic segment of the internal carotid artery: Current status.

The paraophthalmic segment of the internal carotid artery (ICA) originates from the distal border of the cavernous ICA and terminates at the posterior communicating artery. Aneurysms arising from the paraophthalmic segment represent ~5–10% of intradural aneurysms. Due to the advent of endovascular treatment (EVT) techniques, specifically flow-diverting stents (FDSs), EVT has become a good option for these aneurysms. A literature review on EVT for paraophthalmic segment aneurysms is necessary. In this review, we discuss the anatomy of the paraophthalmic segment, classification of the paraophthalmic segment aneurysms, EVT principle and techniques, and prognosis and complications. EVT techniques for paraophthalmic segment aneurysms include coil embolization, FDSs, covered stents, and Woven EndoBridge devices. Currently, coiling embolization remains the best choice for ruptured paraophthalmic segment aneurysms, especially to avoid long-term antiplatelet therapy for young patients. Due to the excessive use of antiplatelet therapy, unruptured paraophthalmic segment aneurysms that are easy to coil should not be treated with FDS. FDS is appropriate for uncoilable or failed aneurysms. Other devices cannot act as the primary choice but can be useful auxiliary tools. Both coiling embolization and FDS deployment can result in a good prognosis for paraophthalmic segment aneurysms. The overall complication rate is low. Therefore, EVT offers promising treatments for paraophthalmic segment aneurysms. In addition, surgical clipping continues to be a good choice for paraophthalmic segment aneurysms in the endovascular era.

Sequential Flow Diversion After Nitinol Stent Placement for a Large, Matricidal Cavernous Internal Carotid Artery Aneurysm: Technical Video.

The Surpass Evolve flow diverter is a novel 64-wire braided intravascular stent approved to treat unruptured large or giant saccular wide-neck or fusiform intracranial aneurysms of the intracranial internal carotid artery.1-3 Flow diverting stents have been used for the treatment of previously stented aneurysms, including residual aneurysms following prior flow diversion.5-8 This patient initially presented with a large symptomatic matricidal cavernous ICA aneurysm4 that was treated with stand-alone Neuroform Atlas stenting at an outside hospital. Here we present a video demonstrating the placement of sequential Surpass Evolve flow diverter stents within a Neuroform Atlas nitinol stent.

Effects of the flow diversion technique on nucleotide levels in intra-cranial aneurysms: A feasibility study providing new research perspectives.

IntroductionThe flow diverter stent (FDS) has become a first-line treatment for numerous intra-cranial aneurysms (IAs) by promoting aneurysm thrombosis. However, the biological phenomena underlying its efficacy remain unknown. We proposed a method to collect in situ blood samples to explore the flow diversion effect within the aneurysm sac. In this feasibility study, we assessed the plasma levels of nucleotides within the aneurysm sac before and after flow diversion treatment.Materials and methodsIn total, 14 patients with unruptured IAs who were selected for FDS implantation were prospectively recruited from February 2015 to November 2015. Two catheters dedicated to (1) FDS deployment and (2) the aneurysm sac were used to collect blood samples within the parent artery (P1) and the aneurysm sac before (P2) and after (P3) flow diversion treatment. The plasma levels of adenosine monophosphate (AMP), adenosine diphosphate (ADP), and adenosine triphosphate (ATP) at each collection point were quantified with liquid chromatography and tandem mass spectrometry.ResultsThe aneurysms were extradural in nine (64.3%) patients and intra-dural in five (35.7%) patients. They presented an average diameter of 15.5 ± 7.1 mm, height of 15.8 ± 4.6 mm, and volume of 2,549 ± 2,794 ml. In all patients (100%), 16 FDS implantations and 42 in situ blood collections were performed successfully without any complications associated with the procedure. The ATP, ADP, and AMP concentrations within the aneurysm sac were decreased after flow diversion (p = 0.005, p = 0.03, and p = 0.12, respectively). Only the ATP levels within the aneurysm sac after flow diversion were significantly correlated with aneurysm volume (adjusted R2 = 0.43; p = 0.01).ConclusionIn situ blood collection within unruptured IAs during a flow diversion procedure is feasible and safe. Our results suggest that the flow diversion technique is associated with changes in the nucleotide plasma levels within the aneurysm sac.

Choroidal and retinal anatomical response following treatment of carotid-ophthalmic aneurysms with flow diverter stents

BackgroundFlow diverter stents(FDSs) are recent additions to the endovascular armament for treating ophthalmic segment aneurysms(OSA). In our study we evaluated the long-term effect of FDS placement on multiple Optical Coherence Tomography(OCT) findings, best corrected visual acuity(BCVA) and intra-ocular pressure(IOP). MethodsA prospective cohort study was conducted in 35 patients treated with a single FDS placement for OSA, between 2013 and 2018. Spectral-domain OCT was used to measure retinal nerve fiber layer thickness, ganglion cell complex thickness, subfoveal choroidal thickness(SFCT), and other stereometric parameters. Choroidal Vascularity Index(CVI) in a 1.5 mm wide subfoveal choroidal area was calculated. BCVA and IOP were also assessed. These measurements, at final follow up, were compared to the untreated fellow eye to evaluate the long-term effect of FDS placement. ResultsThis study included 70 eyes from 35 patients (100% female) with a mean age of 54.9 ± 9.8 years and mean follow-up period of 37.3 ± 18.9 months. No ophthalmic artery occlusion was encountered. The mean CVI was significantly higher in the stented side compared to the fellow normal eye (66.90±1.95 vs 65.05±1.93, p=.001) while mean SFCT was significantly reduced (251.23±68.54 vs 288.78±78.95, p=.037). Differences in the remaining studied parameters did not reach statistical significance. The difference in BCVA between stented and fellow normal eyes was also not significant (0.057±0.213 vs 0.060±0.214, p=.977 in logMAR). ConclusionTreatment with FDSs did not cause permanent visual damage. This study is the first to report a decrease in SFCT with a compensatory increase in CVI following FDS placement for OSA.

The changing landscape of cerebral revascularization surgery: A United Kingdom experience.

We describe the chronological trends in cerebral revascularization surgery through a single-surgeon experience; and we review whether in the context of giant and fusiform cerebral aneurysms, flow-diverting stents have impacted on the use of cerebral revascularization surgery. We review our single institution prospectively collected database of cerebral revascularization procedures between 2006 and 2018. Comparing this to our database of flow-diverting endovascular stent procedures, we compare the treatment of fusiform and giant aneurysms. We describe patient demographics, procedural incidence, complications, and outcomes. Between 2006 and 2018, 50 cerebral revascularization procedures were performed. The incidence of cerebral revascularization surgery is declining. In the context of giant/fusiform aneurysm treatment, the decline in cerebral revascularization is accompanied by a rise in the use of flow-diverting endovascular stents. Thirty cerebral revascularizations were performed for moyamoya disease and 11 for giant/fusiform aneurysm. Four (14%) direct bypass grafts occluded without neurological sequela. Other morbidity included hydrocephalus (2%), transient ischemic attacks (2%), and ischemic stroke (2%). There was one procedure-related mortality (2%). Flow-diverting stents were inserted for seven fusiform and seven giant aneurysms. Comparing the treatment of giant/fusiform aneurysms, there was no significant difference in morbidity and mortality between cerebral revascularization and flow-diverting endovascular stents. We conclude that with the decline in the incidence of cerebral revascularization surgery, there is a need for centralization of services to allow high standards and outcomes to be maintained.