Stent Reconstruction Research Articles

Protrieve Sheath embolic protection during venous thrombectomy: early experience in seventeen patients

PurposeThe Protrieve Sheath (Inari Medical; Irvine, CA) is designed for embolic protection during venous thrombectomy. This report describes experience with its use.Materials and methodsBetween November 2022 and December 2023 (13 months), seventeen patients, including nine (52.9%) females and eight (47.1%) males (mean age 58.8 ± 13.3 years, range 37–81 years), underwent deep venous thrombectomy following the Protrieve Sheath placement for embolic protection. Gender, age, presenting symptoms, procedural indications, obstructed venous segments, the Protrieve Sheath access and deployment sites, thrombectomy devices utilized, need for stent reconstruction, technical success, clinical success, adverse events (the Protrieve Sheath maldeployment or clinically significant embolic events), removed thrombi analyses, and mortality were recorded. Technical success was defined as successful deployment of the Protrieve Sheath funnel central to the thrombectomy site. Clinical success was defined as improvement in presenting venous occlusive symptoms without procedure-related venous thromboembolism.ResultsThe most common presenting symptom was extremity swelling (n = 15; 88.2%). Nine (52.9%) patients had malignant and eight (47.1%) had benign etiologies of venous obstruction. Obstructed venous segments included the inferior vena cava (IVC) and lower extremity (n = 9; 52.9%), isolated lower extremity (n = 4; 23.5%), isolated IVC (n = 2; 11.8%), thoracic central veins and superior vena cava (n = 1; 5.9%), and isolated thoracic central vein (n = 1; 5.9%). The Protrieve Sheath access sites included the right internal jugular vein (n = 15; 88.2%) for IVC and lower extremity obstructions and the right common femoral vein (n = 2; 11.8%) for thoracic central vein and superior vena cava obstructions. The Protrieve sheath funnel deployment locations included intrahepatic IVC in 13 patients (n = 13; 76.5%), suprarenal IVC in two (n = 2; 11.8%), and inferior cavoatrial junction in two (n = 2; 11.8%). Thrombectomy devices used included the ClotTriever System (Inari Medical) (n = 15; 88.2%), the InThrill Thrombectomy System (Inari Medical) (n = 4; 23.5%), the FlowTriever System (Inari Medical) (n = 2; 11.8%), the Lightning Flash 16 Aspiration System (Penumbra; Salt Lake City, UT) (n = 2; 11.8%), the Cleaner Rotational Thrombectomy System (Argon; Plano, TX) (n = 1; 5.9%), and the RevCore Thrombectomy System (Inari Medical) (n = 1; 5.9%). Ten (58.8%) patients required stent reconstruction following thrombectomy. Technical success was achieved in all patients. Clinical success was achieved in 16 (94.1%) patients. No immediate adverse events, including the Protrieve Sheath maldeployment or clinically significant embolic events, occurred.ConclusionUse of the Protrieve Sheath during large-bore venous mechanical thrombectomy resulted in favorable technical and clinical outcomes without device-related adverse events or clinically significant thromboembolic events.

Deep learning reconstruction for coronary CT angiography in patients with origin anomaly, stent or bypass graft.

To develop and validate a deep learning (DL)-model for automatic reconstruction for coronary CT angiography (CCTA) in patients with origin anomaly, stent or bypass graft. In this retrospective study, a DL model for automatic CCTA reconstruction was developed with training and validation sets from 6063 and 1962 patients. The algorithm was evaluated on an independent external test set of 812 patients (357 with origin anomaly or revascularization, 455 without). The image quality of DL reconstruction and manual reconstruction (using dedicated cardiac reconstruction software provided by CT vendors) was compared using a 5-point scale. The successful reconstruction rates and post-processing time for two methods were recorded. In the external test set, 812 patients (mean age, 64.0 ± 11.6, 100 with origin anomalies, 152 with stents, 105 with bypass grafts) were evaluated. The successful rates for automatic reconstruction were 100% (455/455), 97% (97/100), 100% (152/152), and 76.2% (80/105) in patients with native vessel, origin anomaly, stent, and bypass graft, respectively. The image quality scores were significantly higher for DL reconstruction than those for manual approach in all subgroups (4 vs. 3 for native vessel, 4 vs. 4 for origin anomaly, 4 vs. 3 for stent and 4 vs. 3 for bypass graft, all p < 0.001). The overall post-processing time was remarkably reduced for DL reconstruction compared to manual method (11s vs. 465s, p < 0.001). The developed DL model enabled accurate automatic CCTA reconstruction of bypass graft, stent and origin anomaly. It significantly reduced post-processing time and improved clinical workflow.

Cross-attention learning enables real-time nonuniform rotational distortion correction in OCT.

Nonuniform rotational distortion (NURD) correction is vital for endoscopic optical coherence tomography (OCT) imaging and its functional extensions, such as angiography and elastography. Current NURD correction methods require time-consuming feature tracking/registration or cross-correlation calculations and thus sacrifice temporal resolution. Here we propose a cross-attention learning method for the NURD correction in OCT. Our method is inspired by the recent success of the self-attention mechanism in natural language processing and computer vision. By leveraging its ability to model long-range dependencies, we can directly obtain the spatial correlation between OCT A-lines at any distance, thus accelerating the NURD correction. We develop an end-to-end stacked cross-attention network and design three types of optimization constraints. We compare our method with two traditional feature-based methods and a CNN-based method on two publicly-available endoscopic OCT datasets. We further verify the NURD correction performance of our method on 3D stent reconstruction using a home-built endoscopic OCT system. Our method achieves a ∼3 × speedup to real time (26 ± 3 fps), and superior correction performance.

Ongoing Geometric Remodeling of the Parent Artery After Flow-Diverter Stent Reconstruction in Cerebral Aneurysms: The Device Design Matters

Configuration changes of the parent artery (PA) after flow-diverter (FD) stent reconstruction, caused by the bending force of the device, may have an additional role in aneurysm occlusion as a result of the secondary alteration of intra-aneurysmal hemodynamics related to the geometry alteration of the vessel. To determine the degree of PA deformation and aneurysm occlusion rates after deployment of 2 different types of FD. Patients treated with 2 different designs of cobalt-chromium braid (48 and 64 wire braid) structure FD were subject to analysis. Vascular angle changes at the level of the reconstructed segment immediately after FD deployment and at 1 year follow-up were measured and the potential relationship with aneurysmal occlusion rate was analyzed. Forty-two patients harboring 48 aneurysms were included in the present study. The aneurysms were divided into side wall (85.4%) and bifurcation types (14.6%). Twenty-six aneurysms were treated using the Pipeline FD (48 wire braid; 54.2%) and 22 using the Evolve FD (64 wire braid; 45.8%). Of the 48 aneurysms, 42 (87.5%) met the primary end point of complete occlusion at 12 months. The median postdeployment angle change was 7.04°± 4.59° for the Pipeline and 5.05°± 2.49° for the Evolve, whereas the median 12 months follow-up angle change was 15.49°± 10.99° and 10.01°± 8.83°, respectively. PA angle changes were significantly higher in the bifurcation group compared with the side wall group both during procedure and at 12 months follow-up. Angle change had a statistically nonsignificant association with complete aneurysm occlusion. PA deformation starts immediately after deployment and remodeling continues for 1 year after. Aneurysms located in the vessel bifurcation were more prone to PA straightening after FD deployment than were side wall aneurysms. Furthermore, Pipeline seemed to be more prone to inducing vascular deformation, compared with Evolve.

Branched stented anastomosis frozen elephant trunk repair: Early results from a physician-sponsored investigational device exemption study

BackgroundMultisegment thoracic aortic disease typically requires total aortic arch replacement, affects a heterogenous population, and carries a high risk even at centers of excellence. Risk has been associated with the duration of operation and complexity of repair. A novel branched stented anastomosis frozen elephant trunk repair (B-SAFER) technique has been developed at our center and is currently being studied as a physician-sponsored investigation device exemption (PS-IDE). ObjectiveThis study aimed to assess the early safety of using this investigational technique to treat the proximal aorta in subjects with aortic disease involving multiple segments. MethodsThis prospective, single center, nonrandomized study enrolled patients undergoing B-SAFER for acute aortic syndrome (n = 73), aortic aneurysm with chronic aortic dissection (n = 68), degenerative aortic aneurysm (n = 33), or congenital aortic arch disease (n = 4). Devices are delivered antegrade under hypothermic circulatory arrest, and the arch reconstruction is performed as a single anastomosis single stent (SASS; n = 70), single anastomosis multiple stent (SAMA; n = 68), multiple anastomosis single stent (MASS; n = 21), or multiple anastomosis multiple stent (MAMS; n = 16) reconstruction. The primary safety endpoints were operative mortality, disabling stroke, and paraparesis/paralysis. ResultsBetween May 27, 2021, and December 31, 2022, 178 patients underwent B-SAFER in the configurations and for the indications as described above. The median patient age was 65 years (range, 21 to 85 years), and 52 (29%) were female. The median cardiopulmonary bypass time was 188 minutes (interquartile range [IQR], 155 to 226 minutes), and 97% of the patients underwent repair with antegrade brain perfusion for a median of 46 minutes (IQR, 38 to 61 minutes). Operative mortality occurred in 10 patients (5.6%, including 6 [8.2%] with acute dissection, 2 [2.9%] with chronic dissection, 2 [6.1%] with degenerative aneurysm, and 0 with a congenital disorder), disabling stroke in 5 patients (2.9%), and paraparesis in 1 patient. Other serious complications included respiratory failure (n = 20; 11.4%) and acute kidney injury (n = 18; 10%). Thirty-two patients (18%) had undergone second-stage repairs (28 endovascular and 4 open), with 1 operative mortality after that procedure due to distal rupture. Estimated survival was 95% at 30 days, 88% at 90 days, 84% at 6 months, and 79% at 1 year. One-year survival differed by indication (72% for acute dissection, 91% for chronic dissection, 71% for degenerative aneurysm, and 100% for congenital disorders). Conclusions:The B-SAFER technique for total arch replacement in a complex cohort of patients with various indications for surgery is a safe and reproducible operation, as demonstrated by the early results from a very inclusive PS-IDE study. Further follow-up and analysis will help refine the technique. Novel devices to perform this procedure should be developed.

Recurrence of a large intracranial fusiform aneurysm treated with overlapping Pipeline embolization devices: illustrative case.

Flow diversion, specifically with the Pipeline embolization device (PED), represents a paradigm shift in the treatment of intracranial aneurysms. Several studies have demonstrated its efficacy and at times superiority to conventional treatment modalities for aneurysms with a fusiform morphology, giant size, or wide neck. However, there may be a nonsignificant risk of recurrence after flow diversion of these historically difficult-to-treat aneurysms, relative to aneurysms with a more favorable morphology and size (i.e., saccular, narrow necked). To date, only three papers in the literature have demonstrated the recurrence of a completely occluded aneurysm on follow-up. The authors describe a patient with a giant middle cerebral artery fusiform aneurysm treated with multiple telescoping PEDs. On the 3-month follow-up angiogram, there was complete occlusion of the aneurysm. The patient was lost to follow-up and presented 4 years later with a recurrence of the aneurysm between PED segments, requiring retreatment. The patient represented 3 years posttreatment with the need for repeat treatment of the fusiform aneurysm due to separation of the existing PEDs along with stent reconstruction. At the 20-month follow-up after the third treatment, the initial aneurysm target was found to be occluded. This case illustrates the need for long-term follow-up, specifically for patients with giant wide-necked or fusiform aneurysms treated with overlapping PEDs.

The efficacy of ureteroscopic triage in increasing the cure rate of the first-line treatment for a ureterovaginal fistula resulting from radical hysterectomy

Study objectiveTo explore the effect of pretreatment with ureteroscopic triage for iatrogenic ureterovaginal fistula (UVF) resulting from radical hysterectomy. DesignA retrospective cohort study. SettingDepartment of gynecology at a tertiary medical center. PatientsWomen diagnosed with UVF secondary to radical hysterectomy at our center between April 2008 to June 2018. InterventionsThe patients were divided into two groups according to whether pretreatment with ureteroscopic triage was performed. Those in the non-triage group underwent retrograde placement of a double-J stent immediately following diagnosis as the first-line therapy. Patients in the triage group were first evaluated under ureteroscopy, their ureteral injuries were then classified into different grades and then underwent different treatments as the first-line therapy, including stent placement or reconstruction surgeries. The cure rate of the first-line therapy and the timeliness of the implementation of adjuvant radiotherapy were subsequently analyzed. Measurements and main resultsNinety-eight UVF patients were included. The demographics, ECOG status, stage of cervical cancer (FIGO 2009), types and onset time of symptoms were not different between the two groups. There were 54 patients in the nontriage group, with an overall first-line cure rate of 70.4% and a timely implementation rate of adjuvant radiotherapy of 38.5%. There were 44 patients in the evaluation group, with an overall first-line cure rate of 93.2% and a timely implementation rate of adjuvant radiotherapy of 90.0%. The differences were statistically significant (p < 0.001). ConclusionUreteroscopic triage of ureteral injuries can guide the selection of the optimal first-line therapy for patients with UVF secondary to radical hysterectomy, increase the cure rate and ensure the timely implementation of adjuvant radiotherapy.

Stent reconstruction in intracranial atherosclerotic disease related acute ischemic stroke results in high revascularization rates

ObjectivesIntracranial atherosclerotic disease (ICAD) is a major cause of large vessel occlusion (LVO) in acute ischemic stroke (AIS). Our study aimed to analyze the effect of percutaneous transluminal angioplasty and stenting (PTAS) in patients with ICAD undergoing rescue treatment in terms of functional outcome and mortality rate at 90 days and compare the results to LVO with thromboembolic origins. Materials and methodsA retrospective review of a mechanical thrombectomy (MT) single center database from 01/2019 to 09/2021 was carried out using chart review and angiogram analysis. From 469 acute stroke patients, 361 patients were enroled in the study, of whom twenty-four (6.6%) were diagnosed with underlying ICAD and treated with angioplasty and stent reconstruction (PTAS) with a standardized medication protocol. Successful reperfusion, peri-procedural complications, and functional independence at 90 days were collected as outcomes. ResultsThere was no difference in age or admission National Institutes of Health Stroke Scale (NIHSS). Onset to groin puncture (median 460 vs 277 min, P = 0.019) was significantly longer in the ICAD group. The procedure time (median 73 vs 60 min, P = 0.137) did not differ. Successful reperfusion was achieved in 95.8% of ICAD and 91.1% of the remaining patients (P = 0.445). Functional independence (mRS ≤ 2) at 90 days was achieved in 45.8% (11/24) and 42.7% (144/337, (P = 0.767)). The mortality rates (mRS 6) at 90 days were similar (29.2% vs 29.4% (P = 0.983)). ConclusionDespite significantly longer treatment delays, the outcome and revascularization rates of ICAD patients were similar to the thromboembolic cohort. Our proposed protocol of PTAS and medication protocol in ICAD was effective with a similar safety profile as MT in general.

Reciprocal assistance of intravascular imaging in three-dimensional stent reconstruction: Using cross-modal translation based on disentanglement representation.

Accurate and efficient 3-dimension (3D) reconstruction of coronary stents in intravascular imaging of optical coherence tomography (OCT) or intravascular ultrasound (IVUS) is important for optimization of complex percutaneous coronary interventions (PCI). Deep learning has been used to address this technical challenge. However, manual annotation of stent is strenuous, especially for IVUS images. To this end, we aim to explore whether the OCT and IVUS images can assist each other in stent 3D reconstruction when one of them is lack of labeled dataset. We firstly performed cross-modal translation between OCT and IVUS images, where disentangled representation was employed to generate synthetic images with good stent consistency. The reciprocal assistance of OCT and IVUS in stent 3D reconstruction was then conducted by applying unsupervised and semi-supervised learning with the aid of synthetic images. Stent consistency in synthetic images and reciprocal effectiveness in stent 3D reconstruction were quantitatively assessed by F1-Score (FS) on two datasets: OCT-High Definition IVUS (HD IVUS) and OCT-Conventional IVUS (IVUS). The employment of disentangled representation achieved higher stent consistency in synthetic images (OCT to HD IVUS: FS=0.789 vs 0.684; HD IVUS to OCT: FS=0.766 vs 0.682; OCT to IVUS: FS=0.806 vs 0.664; IVUS to OCT: FS=0.724 vs 0.673). For stent 3D reconstruction, the assistance from synthetic images significantly promoted unsupervised adaptation across modalities (OCT to HD IVUS: FS=0.776 vs 0.109; HD IVUS to OCT: FS=0.826 vs 0.125; OCT to IVUS: FS=0.782 vs 0.068; IVUS to OCT: FS=0.815 vs 0.123), and improved performance in semi-supervised learning, especially when only limited labeled data was available. The intravascular images of OCT and IVUS can provide reciprocal assistance to each other in stent 3D reconstruction by cross-modal translation, where the stent consistency in synthetic images was maintained by disentangled representation.

Percutaneous thrombectomy of upper extremity and thoracic central veins using Inari ClotTriever System: Experience in 14 patients.

In the present report, we have described the technical and clinical outcomes of percutaneous thrombectomy in the deep veins of the upper extremity and thorax using the ClotTriever system (Inari Medical, Irvine, CA). Fourteen patients with symptomatic deep venous occlusive disease in the upper extremity deep veins and thoracic central veins who had undergone thrombectomy using the ClotTriever system between October 2020 and January 2022 were reviewed. The technical results, adverse events, imaging follow-up data, and clinical outcomes were recorded. Fourteen patients (seven men and seven women; mean age, 53.6± 13.3years) constituted the study cohort. Of the 14 patients, 9 (64.3%) had had DVT due to intravascular invasion or external compression from known malignancy, 2 (14.3%) had had infected thrombi and/or vegetation due to Staphylococcus aureus refractory to intravenous antibiotic therapy, and 3 (21.4%) had had a benign etiology for thrombus formation. The presenting symptoms included upper extremity and/or facial swelling (n= 14), upper extremity pain (n= 6), fever (n= 2), and dyspnea (n= 1). Thrombectomy with the ClotTriever system was successfully completed in all 14 patients. Seven patients (50.0%) had required additional venous stent reconstruction after thrombectomy to address the underlying stenosis. No major adverse events were noted. All the patients had experienced resolution of the presenting symptoms. For the management of symptomatic deep venous occlusive disease of the upper extremity deep veins and thoracic central veins, thrombectomy using the ClotTriever system was feasible with excellent technical and clinical success.

Abstract No. 595 Endovascular Recanalization and Reconstruction for the Treatment of Symptomatic Venous Ligation

To report techniques, adverse events, and outcomes of endovascular recanalization and stent reconstruction for symptomatic venous ligation. Nine patients, including six (66.7%) men and three (33.3%) women, with mean age 52.9 ± 11.9 years (range, 35-69 years), underwent endovenous recanalization and stent reconstruction for symptomatic venous ligation over eight years. Five (55.6%), one (11.1%), and three (33.3%) patients presented with CEAP 3, 4, and 5 diseases, respectively. External iliac vein ligation occurred in six (66.7%) patients. Ligations were unilateral left, unilateral right, and bilateral in three (33.3%), four (44.4%), and two (22.2%) patients, respectively. Ligation etiologies included surgical injury in four (44.4%), traumatic injury in two (22.2%), chronic lower extremity venous thrombosis in two (22.2%), and malignant resection in one (11.1%) patient. Technical successes, reconstruction parameters, adverse events, hospital stay lengths, clinical outcomes, stent patencies, follow-up evaluations, and mortalities were recorded. Primary single-session recanalization was achieved in nine (100%) patients. Sharp, extravascular, techniques were required in 6 (66.7%) patients. Reconstructions were created with Wallstents, SMART stents, and cTAG devices. Mean number of stents was 2.9 ± 2.5 stents (range, 1-7 stents). Mean stent diameter was 15.5 ± 3.2-mm (range, 12-26-mm). Adverse events (AEs), according to the Society of Interventional Radiology, included one (10.0%) common iliac vein injury (major AE; class D) and one (7.7%) of neck hematoma (minor AE; class A). Mean hospitalization stay length was 1.6 ± 1.6 days (range, 1-6 days). Clinical improvement was achieved in eight (88.9%) patients with six (66.7%) patients downgraded to CEAP 0 disease. Eight (88.9%) reconstructions remained patent with a mean imaging follow-up of 466.4 ± 500.3 days (range, 17-1,400 days). One (9.1%) reconstruction became occluded within sixty days and was unable to be recanalized. Mean total follow-up was 1,086.2 ± 717.5 days (range, 47-2,707 days). Thirty day and study mortality were both zero. Endovenous recanalization and reconstruction is an effective and safe treatment for symptomatic venous ligation.

Intimal Sarcoma after Endovascular Abdominal Aortic Aneurysm Repair.

A 72-year-old man, who was treated 10 years earlier with endovascular aortic aneurysm repair, presented with a fever. Considering the concern of stent graft infection, the patient was treated with antibiotics, but his condition did not improve. He underwent stent graft resection and reconstruction with a Dacron graft. Pathological analysis of the aortic wall and computed tomography revealed recurrent intimal sarcoma, and the patient underwent resurgery. During follow-up, he underwent two additional resections for local recurrence, but he died 17 months later. Our results suggest that intimal sarcoma should be considered during the follow-up after endovascular aortic aneurysm repair.

Feasibility of Endovascular Recanalization in Post-Thrombotic Syndrome of Intentionally Interrupted Inferior Vena Cava.

Surgical plication of inferior vena cava was commonly used until the 1980s for prevention of pulmonary embolism, associated with high incidence of post-thrombotic syndrome (PTS). This study aims to assess the feasibility and safety of endovascular iliocaval recanalization after intentionally surgically interrupted inferior vena cava by external plicating clip. Endovascular iliocaval recanalizations in relation to previous vena cava clip plication were extracted from the retrospective French multicentre database and further analysed. All procedure data were retrospectively reviewed, including technical aspects, technical success and outcomes (clinical response and ultrasound stent patency). From 2016 to 2018, 8 patients from 4 different centres underwent endovascular iliocaval recanalization for PTS in relation to previous caval interruption by clip. Recanalization of iliocaval occlusion through the clip and stent reconstruction were successfully performed for all of them without complications. After angioplasty, plicating clip was opened in U shape (n = 3) or ovalized without significant residual stenosis (n = 5). Patency of the inferior vena cava was maintained for all patients with a mean follow-up of almost two years after stenting. All patients clinically improved. In this small cases series, endovascular recanalization and stenting of surgical vena cava clip plication seem technically feasible without morbidity. Restoration of blood flow through the iliocaval occlusion, using non-invasive endovascular technique, even as late treatment may be durable, with improvement of patient's venous symptoms. 4, Short Communication.

Image Registration-Based Method for Reconstructing Transcatheter Heart Valve Geometry from Patient-Specific CT Scans.

Accurate reconstruction of transcatheter aortic valve (TAV) geometries and other stented cardiac devices from computed tomography (CT) images is challenging, mainly associated with blooming artifacts caused by the metallic stents. In addition, bioprosthetic leaflets of TAVs are difficult to segment due to the low signal strengths of the tissues. This paper describes a method that exploits the known device geometry and uses an image registration-based reconstruction method to accurately recover the in vivo stent and leaflet geometries from patient-specific CT images. Error analyses have shown that the geometric error of the stent reconstruction is around 0.1mm, lower than 1/3 of the stent width or most of the CT scan resolutions. Moreover, the method only requires a few human inputs and is robust to input biases. The geometry and the residual stress of the leaflets can be subsequently computed using finite element analysis (FEA) with displacement boundary conditions derived from the registration. Finally, the stress distribution in self-expandable stents can be reasonably estimated by an FEA-based simulation. This method can be used in pre-surgical planning for TAV-in-TAV procedures or for in vivo assessment of surgical outcomes from post-procedural CT scans. It can also be used to reconstruct other medical devices such as coronary stents.

Precise resection and defect repair of external nose malignant tumor

Objective: To explore the methods for the accurate resection of malignant tumors of the external nose, and the accurate evaluation and repair of tissue defects. Methods: We collected 48 cases with nasal malignant tumors treated in 980 Hospital, Joint Support Force of the People's Liberation Army from January 2010 to June 2020, including 28 males and 20 females, aged 36-86 years. The pathological types of tumors included basal cell carcinomas (n=29), squamous cell carcinomas (n=11), trichilemmal carcinomas(n=6), denoid cystic carcinoma (n=1) and non-Hodgkin lymphoma (n=1). Tumor resection was mainly based on the traditional extended resection determined by the safety margin, and Mohs surgery was used to minimize the scope of resection, for the margin that significantly affected the repairing results, such as the lesion adjacent to the nasal alar margin, nasal columella or deep easy-penetrating margin. All cases obtained tumor resection and primary/secondary defect reconstruction. Results: According to the pathological type and tumor size, the safe resection margin was mainly 4-10 mm, and Mohs surgery was used in 24 cases. Limited-size defects in 38 cases were repaired with double-leaf flaps, kite flaps, nasal dorsum brow flaps, nasolabial flaps or free tissues. Among 10 cases with compound defects, 8 cases were repaired with frontal flaps, including 4 cases with single frontal flaps, 2 cases with additional titanium mesh stent reconstruction and 2 cases with over and out frontal flaps. During follow-up of 1 to 10 years, all the flaps survived without flap necrosis, and the postoperative nasal contour and ventilation were satisfactory. One patient had tumor recurrence 18 months after operation, 2 patients died of cardiovascular and cerebrovascular diseases, and other patients survived without tumors. Conclusions: Mohs surgery can basically meet the requirements for precise resection of external nasal malignant tumors. Individualized application of adjacent tissue flaps and various frontal flaps is a reasonable choice to achieve the satisfactory outcome of external nasal repair and to take into account the complexity of operation.

Percutaneous Y-shape reconstructive biliary stenting in Klatskin cholangiocarcinoma through a single left-sided entry.

Percutaneous Y-shape reconstructive biliary stenting in the Klatskin tumor is typically performed through bilateral biliary access. Single access from a right-side biliary entry is the more commonly used side for biliary access in general. We present a successful Y-shaped biliary stent reconstruction through a single left-side biliary approach. Unilateral single access Y-shaped biliary stenting can be technically challenging; when performed through a left biliary approach, an additional technical challenge may arise due to the unusual combination of Y-shaped biliary stent reconstruction and the single left-side biliary approach. We concluded that percutaneous Y-shaped biliary reconstruction through a left-sided unilateral approach is a technically feasible, less invasive interventional approach in managing Klatskin tumor.SIMILAR CASES PUBLISHED: None.

Portomesenteric and portosystemic venous reconstructions in children using balloon-expandable endoprostheses.

Portomesenteric and portosystemic venous occlusive disease may lead to portomesenteric hypertension, variceal bleeding, ascites and hypersplenism. Data regarding endovascular reconstructive strategies in children, however, are limited. To report technical success, outcome and patency of portomesenteric and portosystemic venous reconstruction using VIABAHN VBX balloon-expandable endoprostheses in pediatric patients. Five pediatric patients (median age: 15years, range: 4-18years), including 3 (60%) boys and 2 (40%) girls, with portomesenteric or portosystemic venous occlusion or recurrent stenosis, underwent balloon-expandable stent graft reconstruction. Presenting symptoms included acute variceal bleeding, without (n = 2, 40%) or with (n = 1, 20%) splenomegaly, and transfusion-dependent chronic melena (n = 1, 20%). One patient was asymptomatic (n = 1, 20%). Preprocedural imaging included Doppler ultrasound and contrast-enhanced computed tomography (CT) in all patients. Initial imaging showed 4 (80%) occlusions and 1 (20%) recurrent stenosis greater than 50%. Technical aspects of the reconstructions, technical successes, clinical outcomes and adverse events were recorded. Technical success was defined as completion of stent graft reconstruction. Adverse events were categorized according to Society of Interventional Radiology criteria. Clinical success was defined as resolution of the presenting symptoms and/or prevention of portal hypertensive sequela. Venous reconstruction was technically successful in all five patients. Stent graft locations included the main portal vein in 2 (40%), the superior mesenteric vein in 1 (20%), autologous Meso-Rex shunt in 1 (20%) and splenocaval shunt in 1 (20%). Six stent grafts were placed (two stent grafts placed in a single patient). Stent grafts had a median diameter of 7mm (range: 6-10mm) and a median length of 59mm (range: 19-79mm). Median fluoroscopy time was 36.6min (range: 13.4-95.8min) and median air kerma was 301.0mGy (range: 218.0-1,148.2mGy). No adverse events occurred. Median clinical follow-up was 18months (range: 6-29months). Median imaging follow-up was 17months (range: 2-29months). Clinical success was achieved in all patients and maintained during the follow-up period. One patient required follow-up intervention with superior mesenteric vein side extension with a self-expanding bare metal stent due to perigraft stenosis detected on CT 3months after stent placement. There were no stent graft occlusions. Portomesenteric and portosystemic venous reconstruction using balloon-expandable stent grafts in pediatric patients was feasible and clinically successful in this preliminary experience. Additional studies are warranted.

Three dimensional reconstruction of coronary artery stents from optical coherence tomography: experimental validation and clinical feasibility

The structural morphology of coronary stents (e.g. stent expansion, lumen scaffolding, strut apposition, tissue protrusion, side branch jailing, strut fracture), and the local hemodynamic environment after stent deployment are key determinants of procedural success and subsequent clinical outcomes. High-resolution intracoronary imaging has the potential to enable the geometrically accurate three-dimensional (3D) reconstruction of coronary stents. The aim of this work was to present a novel algorithm for 3D stent reconstruction of coronary artery stents based on optical coherence tomography (OCT) and angiography, and test experimentally its accuracy, reproducibility, clinical feasibility, and ability to perform computational fluid dynamics (CFD) studies. Our method has the following steps: 3D lumen reconstruction based on OCT and angiography, stent strut segmentation in OCT images, packaging, rotation and straightening of the segmented struts, planar unrolling of the segmented struts, planar stent wireframe reconstruction, rolling back of the planar stent wireframe to the 3D reconstructed lumen, and final stent volume reconstruction. We tested the accuracy and reproducibility of our method in stented patient-specific silicone models using micro-computed tomography (μCT) and stereoscopy as references. The clinical feasibility and CFD studies were performed in clinically stented coronary bifurcations. The experimental and clinical studies showed that our algorithm (1) can reproduce the complex spatial stent configuration with high precision and reproducibility, (2) is feasible in 3D reconstructing stents deployed in bifurcations, and (3) enables CFD studies to assess the local hemodynamic environment within the stent. Notably, the high accuracy of our algorithm was consistent across different stent designs and diameters. Our method coupled with patient-specific CFD studies can lay the ground for optimization of stenting procedures, patient-specific computational stenting simulations, and research and development of new stent scaffolds and stenting techniques.

Abstract No. 69 Bifurcated hepatocaval stent reconstruction for treatment of hepatic venous outflow obstruction in orthotopic liver transplantation

Hepatic venous outflow obstruction (HVOO) is a complication of orthotopic liver transplantation (OLT). This study reported efficacy and safety of bifurcated hepatocaval stent reconstruction for treatment of anastomotic stenoses in OLT.

Endovascular treatment of superior vena cava syndrome does not preclude continued use of indwelling hemodialysis and chemotherapy lines

Obstruction of the Super Vena Cava (SVC) can result in symptoms, such as facial plethora and swelling, and be due to a variety of underlying causes besides lung malignancies, the rates of which have changed over time; the underlying etiology is used to determine the best management strategy. This case report aims to discuss the role of etiology in determining the best initial treatment for SVC syndrome (SVCS) and outlines the unique management for a patient that represents the changing demographics of SVCS causes. A 73-year-old male with end-stage renal disease and metastatic carcinoma of the colon presented with swelling of the jaw, neck, and tongue. Computed tomography (CT) scan showed chronic thrombosis of the SVC and bilateral brachiocephalic veins. He had been receiving hemodialysis and chemotherapy through central venous catheters (CVCs) that traversed the SVC and terminated in the right atrium. Treatment involved double-barrel stent reconstruction of the SVC with a snare technique to temporarily reposition the chemotherapy port catheter and exchange of the hemodialysis catheter. After this single procedure, he experienced relief of symptoms without disrupting the use of his CVCs for further hemodialysis or chemotherapy appointments. For cases of SVCS due to underlying lung malignancies, which has been and remains the most common cause, endovascular stenting is reserved as a palliative measure when treatment of a refractory malignancy fails to resolve the obstruction and for when symptoms are severe because most cases are not life-threatening. However, increased use of CVCs has caused a rise in SVCS due to thrombosis, for which stenting is the first-line treatment. Of the few previously published case reports that depict using a snare technique to temporarily reposition a CVC, they all describe cases due to lung malignancies. Outlining this case presentation can increase awareness of thrombotic stenosis as an increasingly common cause of SVCS, which may occur in patients with a broader range of underlying conditions, ages, and life expectancies and require a wider array of physicians to be knowledgeable of management strategies. Furthermore, detailing this unique technique can provide therapeutic alternatives that show how endovascular interventions do not disrupt interdisciplinary treatment plans or preclude continued use of CVCs. While stenting technology has improved dramatically since its inception, follow-up on stent patency will help determine if expanding treatment for lower acuity cases is beneficial. Endovascular stenting is the treatment of choice for thrombotic causes of SVCS, which is becoming more common due to the increased use of CVCs. Techniques to temporarily reposition CVCs intra-procedurally allow for limited disruption in multidisciplinary treatment plans for patients with complex underlying conditions.