Direct Branches Research Articles

A New Bailout Maneuver to Manage Type IIIa Endoleak Due to Displaced Renal Bridging Stent Graft in Narrow Aorta.

To present endovascular management of an intraoperative type IIIc endoleak (EL) in a patient with migration of the right renal artery (RRA) bridging stent graft (BSG) during branched aortic aneurysm repair. The technique is demonstrated in an 80-year-old woman who underwent branched endograft repair of a symptomatic 6-cm type II TAAA. The t-Branch thoracoabdominal stent graft was positioned without difficulty. A "partial graft deployment" was performed, with the distal portion of the device remaining inside the delivery system and the right renal and superior mesenteric arteries were stented. When the constraining wires were removed, the RRA BSG migration from the branch was displayed, due to endograft twisting resulting in a horizontal rotation of the t-Branch. The RRA BSG remained oriented upward with the proximal edge positioned above the distal edge of the directional branch, making cannulation very difficult. This bailout technique uses a balloon placed at the level of the RRA BSG through the celiac artery (CA) directional branch; keeping the balloon inflated and in thrust, the edge of the BSG has moved downward making it possible to engage it and relining through the RRA directional branch. This paper describes an endovascular bailout technique for relining a displaced bridging stent graft, oriented upwards with the proximal edge positioned above the distal edge of the directional branch. This sophisticated technique adds to the spectrum of bailout techniques that can be applied in cases of type IIIa EL with migration and complete separation of BSG.

Influence of Anatomical Spatial Architecture of Pinus devoniana on Pressure Gradients Inferred from Coupling Three-Dimensional CT Imaging and Numerical Flow Simulations

Conifer forests in Michoacán are facing climate change. Pinus devoniana Lindley, with natural distribution in the state, has shown certain adaptability, and knowing the influence of anatomy in the flow system is essential to delimit how it contributes to safety margins and water efficiency. For this, the pressure gradients in the cell lumens and their ramifications were analyzed by numerical simulations of flow throughout the real microstructure. Xylem were evaluated in radial, tangential and longitudinal directions. With the skeletonization of lumens and their constrictions, a branching system of interconnection between tracheids, ray cells, intercellular chambers, extensions, and blind pits were identified. In the simulation, the branched system bypasses the longitudinal fluid passage through the pores in membranes of pairs of pits to redirect it through the direct path branching, contributing to safety margins and water efficiency. Thus, resilience at low pressures because of the lower pressure drop in the extensions. The interface between the branching system and the cell lumens are sites of higher pressure gradient, more conducive to water-vapor formation or air leakage in the face of the lowest pressure system. The flow lines move along easy paths, regardless of the simulated flow direction. Deposits in the cell extensions were shown to be attached to the S3 layer of the cell wall, leaving the center of the duct free to flow. It is concluded that the spatial architecture of the xylem anatomy of Pinus dvoniana is a factor in the resilience at low pressures due to high water stress of the species.

Growth hormone promotes myelin repair after chronic hypoxia via triggering pericyte-dependent angiogenesis.

White matter injury (WMI) causes oligodendrocyte precursor cell (OPC) differentiation arrest and functional deficits, with no effective therapies to date. Here, we report increased expression of growth hormone (GH) in the hypoxic neonatal mouse brain, a model of WMI. GH treatment during or post hypoxic exposure rescues hypoxia-induced hypomyelination and promotes functional recovery in adolescent mice. Single-cell sequencing reveals that Ghr mRNA expression is highly enriched in vascular cells. Cell-lineage labeling and tracing identify the GHR-expressing vascular cells as a subpopulation of pericytes. These cells display tip-cell-like morphology with kinetic polarized filopodia revealed by two-photon live imaging and seemingly direct blood vessel branching and bridging. Gain-of-function and loss-of-function experiments indicate that GHR signaling in pericytes is sufficient to modulate angiogenesis in neonatal brains, which enhances OPC differentiation and myelination indirectly. These findings demonstrate that targeting GHR and/or downstream effectors may represent a promising therapeutic strategy for WMI.

α-Catenin and Piezo1 Mediate Cell Mechanical Communication via Cell Adhesions.

Cell-to-cell distant mechanical communication has been demonstrated using in vitro and in vivo models. However, the molecular mechanisms underlying long-range cell mechanoresponsive interactions remain to be fully elucidated. This study further examined the roles of α-Catenin and Piezo1 in traction force-induced rapid branch assembly of airway smooth muscle (ASM) cells on a Matrigel hydrogel containing type I collagen. Our findings demonstrated that siRNA-mediated downregulation of α-Catenin or Piezo1 expression or chemical inhibition of Piezo1 activity significantly reduced both directional cell movement and branch assembly. Regarding the role of N-cadherin in regulating branch assembly but not directional migration, our results further confirmed that siRNA-mediated downregulation of α-Catenin expression caused a marked reduction in focal adhesion formation, as assessed by focal Paxillin and Integrin α5 localization. These observations imply that mechanosensitive α-Catenin is involved in both cell-cell and cell-matrix adhesions. Additionally, Piezo1 partially localized in focal adhesions, which was inhibited by siRNA-mediated downregulation of α-Catenin expression. This result provides insights into the Piezo1-mediated mechanosensing of traction force on a hydrogel. Collectively, our findings highlight the significance of α-Catenin in the regulation of cell-matrix interactions and provide a possible interpretation of Piezo1-mediated mechanosensing activity at focal adhesions during cell-cell mechanical communication.

Plug-Based Embolization Techniques of Aortic Side Branches during Standard and Complex Endovascular Aortic Repair.

Vascular plugs are an evolving family of vessel occluders providing a single-device embolization system for large, high-flow arteries. Nitinol mesh plugs and polytetrafluoroethylene membrane plugs are available in different configurations and sizes to occlude arteries from 3 to 20 mm in diameter. Possible applications during complex endovascular aortic procedures are aortic branch embolization to prevent endoleak or to gain an adequate landing zone, directional branch occlusion, and false lumen embolization in aortic dissection. Plugs are delivered through catheters or introducers, and their technical and clinical results are comparable to those of coil embolization. Plugs are more accurate than coils as repositionable devices, less prone to migration, and have fewer blooming artifacts on postoperative computed tomography imaging. Their main drawback is the need for larger delivery systems. This narrative review describes up-to-date techniques and technology for plug embolization in complex aortic repair.

Early outcomes of fenestrated and/or branched endovascular repair of complex aortic aneurysms (F/B-EVAR); A single-center experience

Background: Open surgical repair of juxta-, para- and thoracoabdominal aortic aneurysms (TAAA) has been the gold-standard for patients fit for surgery. However, endovascular repair of complex aortic aneurysms using devices implementing directional branches or fenestrations for incorporation of reno-visceral target vessels (TV) has gained widespread attention, due to its lower mortality and complication rate and its more attractive profile for high-risk patients. Nonetheless, complex endovascular technologies require meticulous abidance to protocols for successful application. Methods: A retrospective analysis of prospectively collected data from a single, tertiary center was undertaken, including all patients undergoing complex aortic endovascular repair with fenestrated (F-EVAR) of branched devices (B-EVAR) from a 5-year time period (2018-2023). Primary outcomes included 30-day mortality, while secondary outcomes included primary TV patency, acute kidney injury (AKI), spinal cord ischemia (SCI), myocardial infarction (MI) and stroke rates. Results: Of 74 patients (mean age: 69 ± 5.6 years-old, 98% males), 31 (42.6) and 43 (57.6%) were treated by F-EVAR and B-EVAR, respectively. Mean aneurysm diameter was 68 ± 1.8cm, with 15 (20.5%) juxtarenal AAA, 27 (35.6%) pararenal AAA, 16 (21.9%) type IV TAAA, 6 (8.2%) type III TAAA, and 10 (13.7%) type II TAAA treated. Sixteen (21.6%) patients were treated due to failed-EVAR. In total, 272 TV were successfully revascularized. Thirty-day mortality was 8.1%. Primary TV patency rate was 99.2% (270/272). Endoleak rate was 8.1% (6/74). No cases of AKI or MI were observed. One (1.3%) case of hemorrhagic stroke was observed. Three cases (4%) of SCI were observed, including one temporary paraparesis and two permanent paraplegia cases. Reintervention rate was 5.4%, including two cases of renal artery stent thrombosis revascularization procedures. Conclusions: Endovascular repair of complex aortic aneurysms is feasible, with good perioperative outcomes. Adherence to precise protocols covering every technical aspect of patient care is warranted for satisfactory outcomes.

Computational Flow Simulation Reveals Adverse Haemodynamics Associated With Directional Branch Occlusion After Fenestrated Branched EVAR

Computational Flow Simulation Reveals Adverse Haemodynamics Associated With Directional Branch Occlusion After Fenestrated Branched EVAR

Prospective evaluation of upper extremity access and total transfemoral approach during fenestrated and branched endovascular repair

ObjectiveTotal transfemoral (TF) access has been increasingly used during fenestrated-branched endovascular aortic repair (FB-EVAR). However, it is unclear whether the potential decrease in the risk of cerebrovascular events is offset by increased procedural difficulties and other complications. The aim of this study was to compare outcomes of FB-EVAR using a TF vs upper extremity (UE) approach for target artery incorporation. MethodsWe analyzed the clinical data of consecutive patients enrolled in a prospective, nonrandomized clinical trial in two centers to investigate the use of FB-EVAR for treatment of complex abdominal aortic aneurysms (CAAA) and thoracoabdominal aortic aneurysms (TAAA) between 2013 and 2022. Patients were classified into TF or UE access group with a subset analysis of patients treated using designs with directional branches. End points were technical success, procedural metrics, 30-day cerebrovascular events defined as stroke or transient ischemic attack, and any major adverse events (MAEs). ResultsThere were 541 patients (70% males; mean age, 74 ± 8 years) treated by FB-EVAR with 2107 renal-mesenteric TAs incorporated. TF was used in175 patients (32%) and UE in 366 patients (68%) including 146 (83%) TF and 314 (86%) UE access patients who had four or more TAs incorporated. The use of a TF approach increased from 8% between 2013 and 2017 to 31% between 2018 and 2020 and 96% between 2021 and 2022. Compared with UE access patients, TF access patients were more likely to have CAAAs (37% vs 24%; P = .002) as opposed to TAAAs. Technical success rate was 96% in both groups (P = .96). The use of the TF approach was associated with reduced fluoroscopy time and procedural time (each P < .05). The 30-day mortality rate was 0.6% for TF and 1.4% for UE (P = .67). There was no early cerebrovascular event in the TF group, but the incidence was 2.7% for UE patients (P = .035). The incidence of MAEs was also lower in the TF group (9% vs 18%; P = .006). Among 237 patients treated using devices with directional branches, there were no significant differences in outcomes except for a reduced procedural time for TF compared with UE access patients (P < .001). ConclusionsTF access was associated with a decreased incidence of early cerebrovascular events and MAEs compared with UE access for target artery incorporation. Procedural time was decreased in TF access patients irrespective of the type of stent graft design.

Theoretical Analysis of a Simple Hyperbolic Metamaterial Wave Splitter

Wave splitter for TE and TM wave is critical components in the integrated optics. Current technologies mainly rely on two types of designs to separate TE and TM waves: directional coupler type and branch type, but these designs are generally complex. By exploring the transmission behavior of the waves in the hyperbolic metamaterial and the distinct dispersion relationships of TE and TM waves in these materials, we have designed a wave splitter with a simple structure. Under different parameter conditions, we can get the pure TE wave or pure TM wave in the transmission region. Furthermore, if the specific condition is satisfied, we can even get the pure TE wave in the reflection or transmission region and the pure TM wave in the other region at the same time. All theoretical analysis results have been verified by using COMSOL Multiphysics simulation software.

Hepatocellular carcinoma vascularization: CT angiography variations identifying arteries feeding the tumour

BackgroundHepatic arterial anatomy is important in performing many surgical and endovascular procedures. Familiarity with variations in the hepatic arterial anatomy is essential to achieving adequate embolization. In some patients, in addition to anatomic variations of the hepatic arteries, different extrahepatic collateral arteries may provide partial or total vascular supply to hepatocellular carcinoma (HCC), which makes transcatheter arterial chemoembolization (TACE) technically challenging. We aim to evaluate the different feeding vessels of HCC using multi-detector computed tomography angiography (MDCTA) as a pre-procedural step before planning suitable management.ResultsOne hundred patients with 150 focal HCC lesions were involved in our study. The anatomy of the blood supply and the morphological characteristics of HCC, including the size, location, and history of previous hepatitis, were quantitatively assessed and statistically analysed. The number of patients who had classic hepatic arterial supply for the HCC lesions in our study was 54 (54%). The number of patients with additional extrahepatic supply is 26, while the number of patients with anatomical vascular variants is 20. Among these 26 patients with extrahepatic (parasitic) blood supply, six patients were supplied by the right inferior phrenic artery, four patients were supplied by the right internal mammary artery, and two patients were supplied by each other type of extrahepatic feeder, which are the left inferior phrenic artery, left internal mammary artery, left gastric artery, cystic artery, right lumbar artery, direct branch from the aorta, omental arteries, right renal artery, and LHA from the LGA. Twelve of the 20 patients with anatomical vascular variants had replaced RHA from the SMA; four patients had replaced LHA from the LGA; two patients had replaced RHA from the GDA; and two patients had replaced CHA from the SMA. Only 50 cases of CT findings were correlated with the data from the interventional procedures of these patients.ConclusionsBecause of the differences in HCC blood supply between typical, parasitic, and anatomical vascular variants, MDCTA has significant clinical significance prior to TACE and any interventional procedure.

Incorporation of internal iliac arteries as target vessels during physician-modified fenestrated branched endovascular repair of pararenal abdominal aortic aneurysm with concomitant bilateral short common iliac artery aneurysms

This report describes an alternative endovascular approach to iliac branch devices for treatment of an abdominal aortic aneurysm with concomitant bilateral short common iliac aneurysms. The short distance between the renal arteries and internal iliac artery origins made the addition of distal iliac branch devices to the proximal fenestrated stent graft challenging. We elected to perform physician-modified fenestrated branched endovascular repair, using four fenestrations for the visceral and renal arteries and an additional two directional branches for the bilateral internal iliac arteries. The patient recovered uneventfully, and the 24-month follow-up imaging shows successful aneurysm exclusion with patent internal iliac artery branches.

Effect of narrow paravisceral aorta on target vessel instability after fenestrated and branched endovascular aortic repair

ObjectiveTo investigate the effect of narrow paravisceral aorta (NPA) on target vessel instability (TVI) after fenestrated-branched endovascular aortic repair. MethodsWe conducted a single-center retrospective study (2014-2023) of patients treated by fenestrated-branched endovascular aortic repair for thoracoabdominal aortic aneurysms (TAAA) or pararenal aortic aneurysms. The paravisceral aorta was defined as the aortic segment limited by the diaphragmatic hiatus proximally and the emergence of lower renal artery distally, and was considered “narrow” in case of a minimum inner diameter of <25 mm. The minimum aortic diameter, location, longitudinal extension, angulation, calcification, and thrombus thickness of NPA were evaluated at the preoperative computed tomography angiogram. End points were 30-day technical success and freedom from TVI. ResultsThere were 142 patients with JRAA/pararenal aortic aneurysm (n = 85 [59%]) and extent IV (n = 24 [17%]) or extent I-III (n = 33 [23%]) TAAA, with 513 target arteries successfully incorporated through a fenestration (n = 294 [57%]) or directional branch (n = 219 [43%]). A NPA was present in 95 patients (70%), 73 (86%) treated by fenestrated endovascular aortic repair (FEVAR) and 22 (39%) by branched endovascular aortic repair (BEVAR). The overall 30-day mortality was 2% and technical success was 99%, without differences between NPA and non-NPA (P = .99). Kaplan-Meier estimated freedom from TVI at 4 years was 82%, 81% (95% CI, 75-95) in patients with a NPA and 80% (95% CI, 68-94) and in those without NPA (P = .220). The result was maintained for both FEVAR (NPA: 81% [95% CI, 62-88]; non-NPA: 76% [95% CI, 60-99]; P = .870) and BEVAR (NPA: 77% [95% CI, 69-99]; non-NPA: 80% [95% confidence interval (CI) 66-99]; P = .100). After multivariate analysis, the concomitant presence of a NPA <20 mm and angulation of >30° was significantly associated with TVI in FEVAR (HR, 3.21; 95% CI, 1.03-48.70; P = .036), being the result mostly driven by target vessel occlusion. In BEVAR, a NPA diameter of <25 mm was not associated with TVI (HR, 2.02; 95% CI, 0.59-5.23; P = .948); after multivariate analysis, the use of outer branches in case of a NPA longitudinal extension of >25 mm (hazard ratio [HR], 3.02; 95% CI, 1.01-36.33; P = .040) and NPA severe calcification (HR, 1.70; 95% CI, 1.00-22.42; P = .048) were associated with a higher chance for TVI. ConclusionsFEVAR and BEVAR are both feasible in cases of NPA and provide satisfactory target vessels durability. The use of outer branches should be avoided in cases with an inner aortic diameter of <25 mm with a longitudinal extension of >25 mm or moderate to severe NPA calcifications. In FEVAR, bridging stent patency may be negatively influenced by NPA of <20 mm in association with aortic angulation of >30°.

Fate of primary determinate and indeterminate target vessel endoleaks after fenestrated-branched endovascular aortic repair

ObjectiveThe aim of this study was to investigate the outcomes of primary determinate and indeterminate target vessel endoleaks (TVELs) after fenestrated-branched endovascular aortic repair (F-BEVAR). MethodsWe conducted a single-center retrospective study (2014-2023) on F-BEVAR for thoracoabdominal (TAAAs) or pararenal aortic aneurysms (PRAAs). TVELs were classified as “primary” if present at the first postoperative computed tomography angiogram. Endoleaks were defined “determinate” (dELs) if the cause (type Ic or IIIc) and implicated target vessel were identifiable and “indeterminate” (iELs) if contrast enhancement was detectable at the level of fenestrations/branches without any evident source. Endoleaks involving multiple inflows (type II and target vessels) were defined as “complex” (cELs). Endpoints were endoleak spontaneous resolution, 1-year aneurysm sac failure to regress (>5 mm diameter decrease), and 4-year endoleak-related secondary interventions. Kaplan-Meier estimates and Cox regression were used for the analysis. ResultsThere were 142 patients with JRAAs/PRAAs (n = 85; 60%) or TAAAs (n = 57; 40%), with 513 target arteries incorporated through a fenestration (n = 294; 57%) or directional branch (n = 219; 43%). Fifty-nine primary TVELs (12%) were identified in 35 patients (25%), a dEL in 20 patients (14%) and iEL in 15 (11%); 22 (15%) had a determinate or indeterminate cEL. Overall spontaneous resolution rate was 75% (95% confidence interval [CI], 51%-87%) at 4 years. cELs (odds ratio [OR], 5.00; 95% CI, 1.10-49.4; P < .001) and iELs after BEVAR (OR, 9.43; 95% CI, 3.41-56.4; P = .002) were more likely to persist >6 months, and persistent forms were associated with sac failure to regress at 1 year (OR, 1.72; 95% CI, 1.03-12.59; P = .040). Overall freedom from endoleak-related reinterventions was 85% (95% CI, 79%-92%) at 4 years, 92% (95% CI, 87%-97%) for those without primary TVELs and 62% (95% CI, 46%-84%) for those with any primary TVEL (P < .001). In particular, cELs (hazard ratio, 1.94; 95% CI, 1.4-18.81; P = .020) were associated with an increased need for reintervention. In case a secondary intervention was needed, iEL or cEL had an increased risk for multiple secondary procedures (hazard ratio, 2.67; 95% CI, 1.22-10.34; P = .034). ConclusionsPrimary TVELs are frequent after F-BEVAR, and a clear characterization of the endoleak source by computed tomography angiogram is not possible in 40% of patients. Most primary TVELs spontaneously resolve, but during follow-up, patients with any primary TVEL experience a worsened freedom from endoleak-related reinterventions that is mostly driven by persistence of cELs and post-BEVAR iELs. Multiple secondary procedures may be required in case of iELs or cELs.

Superior mesenteric artery-related outcomes in fenestrated/branched endografting for complex aortic aneurysms.

Early/follow-up durability of superior mesenteric artery (SMA) stent-grafts is crucial after fenestrated/branched endografting (FB-EVAR) in complex abdominal aortic aneurysms (CAAAs) and thoracoabdominal aortic aneurysms (TAAAs). The study aimed to report early/midterm outcomes of SMA incorporated during FB-EVAR procedures. FB-EVAR procedures performed between 2016 and 2021 in a single institution were reviewed. Anatomical SMA characteristics were analyzed. The SMA configuration was classified into three types according to the angle between the SMA main trunk and the aorta: (A) perpendicular, (B) downward, and (C) upward. SMA-related technical success (SMA-TS: cannulation and stenting, patency at completion angiography without endoleak, stenosis/kinking, dissection, bleeding, and 24-h mortality) and SMA-adverse events (SMA-AEs: one among bowel ischemia, stenosis, occlusion, endoleak, reinterventions, or SMA-related mortality) were assessed. Two hundred FB-EVAR procedures with SMA as the target artery were performed. The indication for FB-EVAR was CAAAs and TAAAs in 99 (49%) and 101 (51%) cases, respectively. The SMA configuration was A, B, and C in 132 (66%), 63 (31%), and 5 (3%) cases, respectively. SMA was incorporated with fenestrations and branches in 131 (66%) and 69 (34%) cases, respectively. Directional branch (P < .001), aortic diameter ≥35 mm at the SMA level (P < .001), and ≥2 SMA bridging stent-grafts (P = .001) were more frequent in TAAAs. Relining of the SMA stent-graft with a bare metal stent was necessary in 41 (21%) cases to correct an acute angle between the stent-graft and native artery (39), stent-graft stenosis (1), or SMA dissection (1). Relining was associated with type A or C SMA configuration (OR: 17; 95% CI: 1.8-157.3; P = .01). SMA-TS was achieved in all cases. Overall, 15 (7.5%) patients had SMA-AEs [early: 9 (60%), follow-up: 6 (40%)] due to stenosis (2), endoleak (8), and bowel ischemia (5). Aortic diameter ≥35 mm at the SMA level was an independent risk factor for SMA-AEs (OR: 4; 95% CI: 1.4-13.8; P = .01). Fourteen (7%) patients died during hospitalization with 10 (5%) events within the 30-postoperative day. Emergency cases (OR: 33; 95% CI: 5.7-191.3; P = .001), peripheral arterial occlusive disease (OR: 14; 95% CI: 2.3-88.8; P = .004), and bowel ischemia (OR: 41; 95% CI: 1.9-87.9; P = .01) were risk factors for 30-day/in-hospital mortality. The mean follow-up was 32 ± 24 months; estimated 3-year survival was 81%, with no case of late SMA-related mortality or occlusion. The estimated 3-year freedom from overall and SMA-related reinterventions was 74% and 95%, respectively. SMA orientation determines the necessity of stent-graft relining. Aortic diameter ≥35 mm at the SMA level is a predictor of SMA-AEs. Nevertheless, SMA-related outcomes of FB-EVAR are satisfactory, with excellent technical success and promising clinical outcomes during the follow-up.

Colloidal directional structures at a nematic liquid crystal–air interface

ABSTRACT We present a variety of structures formed by colloidal droplets at a nematic liquid crystal – air interface, where the elastic dipole–dipole, quadrupole–quadrupole and dipole–quadrupole interactions are all essentially involved. The colloidal structures observed not only include chains with kinks or clusters but also comprise directional structures, such as directional chains and branches, whose direction is associated with the tilting director in the liquid crystal layer. The dipole–quadrupole interaction, originating from the polydispersity of the droplets, plays a central role for the formation of these directional structures. Clusters consisting of directional branches and chains are also observed and found to be fractal statistically.

Conditional temporal GAN for intent-aware vessel trajectory prediction in the precautionary area

Accurate vessel trajectory prediction is crucial for ensuring maritime traffic safety and efficiency, particularly in precaution areas characterized by multi-waterway branch merging and frequent traffic conflicts. However, predicting trajectories in these areas poses significant challenges due to the uncertain future intents of different directional branches resulting in diverse motion patterns and multiple possible paths. To address this issue and minimize the prediction error, we propose a conditional temporal generative adversarial network (CTGAN). Specifically, in this method, the trajectory generator is developed to capture the inherently dynamic of ship motions and outputs the future trajectory proposals, while the intent classifier is designed to evaluate whether the trajectory proposals are consistent with the hidden intention. With the adversarial training strategy, the trajectory generator and intent classifier form a closed loop, feedback informative signals to each other that enables generating the intent-constrained trajectory. In addition, a mixed adversarial loss function was designed to capture the spatial–temporal dependencies among the vessel motions for producing consistent trajectories that complied with plausible ship dynamics. Experiments on extensive naturalistic vessel trajectory data demonstrate that compared with the baseline methods, the proposed model achieves comparable or better prediction performance.

Novel Technique for Intentional Occlusion of Directional Branches During Complex Endovascular Aortic Repair Using Microvascular Plugs.

To demonstrate the feasibility and outcomes of using the microvascular plug (MVP) for intentional occlusion of directional branches (DB) during complex endovascular aortic procedures. Two patients were treated with the off-the-shelf four-branched Zenith t-Branch thoracoabdominal stent-graft (Cook Medical, Bloomington, Ind). In both cases, the renal arteries (on one side in patient #1 and on both sides in patient #2, respectively) were occluded at time of index intervention. Preoperative planning included the intentional occlusion of each DB with one 7Q-MVP. Technical success was achieved in all cases and maintained at mid-term follow-up (12months and 36months, respectively). Use of the MVP appears to be feasible and effective for intentional occlusion of DB during complex endovascular aortic repair. This novel and simple technique may present some unique technical advantages, allowing precise placement of the device while avoiding extension using a bridging stent and DB cannulation with larger sheaths.

Changes in renal-mesenteric duplex ultrasound velocities after fenestrated and branched endovascular aortic aneurysm repair

ObjectiveStenting of renal and mesenteric vessels may result in changes in velocity measurements due to arterial compliance, potentially giving rise to confusion about the presence of stenosis during follow-up. The aim of our study was to compare preoperative and postoperative changes in peak systolic velocity (PSV, cm/s) after placement of the celiac axis (CA), superior mesenteric artery (SMA) and renal artery (RAs) bridging stent grafts during fenestrated-branched endovascular aortic repair (FB-EVAR) for treatment of complex abdominal aortic aneurysms (AAA) and thoracoabdominal aortic aneurysms. MethodsPatients were enrolled in a prospective, nonrandomized single-center study to evaluate FB-EVAR for treatment of complex AAA and thoracoabdominal aortic aneurysms between 2013 and 2020. Duplex ultrasound examination of renal-mesenteric vessels were obtained prospectively preoperatively and at 6 to 8 weeks after the procedure. Duplex ultrasound examination was performed by a single vascular laboratory team using a predefined protocol including PSV measurements obtained with <60° angles. All renal-mesenteric vessels incorporated by bridging stent grafts using fenestrations or directional branches were analyzed. Target vessels with significant stenosis in the preoperative exam were excluded from the analysis. The end point was variations in PSV poststent placement at the origin, proximal, and mid segments of the target vessels for fenestrations and branches. ResultsThere were 419 patients (292 male; mean age, 74 ± 8 years) treated by FB-EVAR with 1411 renal-mesenteric targeted vessels, including 260 CAs, 409 SMAs, and 742 RAs. No significant variances in the mean PSVs of all segments of the CA, SMA, and RAs at 6 to 8 weeks after surgery were found as compared with the preoperative values (CA, 135 cm/s vs 141 cm/s [P = .06]; SMA, 128 cm/s vs 125 cm/s [P = .62]; RAs, 90 cm/s vs 83 cm/s [P = .65]). Compared with baseline preoperative values, the PSV of the targeted vessels showed no significant differences in the origin and proximal segment of all vessels. However, the PSV increased significantly in the mid segment of all target vessels after stent placement. ConclusionsStent placement in nonstenotic renal and mesenteric vessels during FB-EVAR is not associated with a significant increase in PSVs at the origin and proximal segments of the target vessels. Although there is a modest but significant increase in velocity measurements in the mid segment of the stented vessel, this difference is not clinically significant. Furthermore, PSVs in stented renal and mesenteric arteries were well below the threshold for significant stenosis in native vessels. These values provide a baseline or benchmark for expected PSVs after renal-mesenteric stenting during FB-EVAR.

The superior vesical artery: A review of conflicting definitions and how these could affect invasive procedures.

Since the superior umbilical artery is the only functioning branch of the patent umbilical artery, some anatomical and surgical books/atlases fail to clarify that it is a branch of the umbilical artery and not a direct branch of the anterior division of the internal iliac artery and so specifically state that it is a direct branch of the internal iliac artery. This discrepancy in nomenclature can obviously affect invasive procedures and communication between physicians. Therefore, the present review is intended to highlight this issue. The term "superior vesical artery" was searched using standard search engines, for example, PubMed and Google Scholar. Several standard and specialized anatomy textbooks were also examined to ascertain how the superior vesical artery was described. Thirty-two articles were identified that used the terms "superior vesical artery" or "superior vesical arteries." After applying exclusion criteria, in 28 papers, the definition of the superior vesical artery was undetermined in eight, described as a direct branch of the internal iliac artery in 13, described as a branch of the umbilical artery in six, and defined as being equivalent to the umbilical artery in one. Of the sampled textbooks, some defined the superior vesicle artery as a branch of the umbilical artery, some as a direct branch of the internal iliac artery and some as both. Taken all together, most define the superior vesical artery as a branch of the umbilical artery. As the superior vesical artery is described as a branch of the umbilical artery in the internationally accepted terminology (Terminologia Anatomica), we recommend that this definition be used by anatomists and physicians alike so that communication is clear.

Three‐dimensional phenotyping of peach tree‐crown architecture utilizing terrestrial laser scanning

AbstractTree training systems for temperate fruit have been developed throughout history by pomologists to improve light interception, fruit yield, and fruit quality. These training systems direct crown and branch growth to specific configurations. Quantifying crown architecture could aid the selection of trees that require less pruning or that naturally excel in specific growing/training system conditions. Regarding peaches [Prunus persica (L.) Batsch], access tools such as branching indices have been developed to characterize tree‐crown architecture. However, the required branching data (BD) to develop these indices are difficult to collect. Traditionally, BD have been collected manually, but this process is tedious, time‐consuming, and prone to human error. These barriers can be circumnavigated by utilizing terrestrial laser scanning (TLS) to obtain a digital twin of the real tree. TLS generates three‐dimensional (3D) point clouds of the tree crown, wherein every point contains 3D coordinates (x, y, z). To facilitate the use of these tools for peach, we selected 16 young peach trees scanned in 2021 and 2022. These 16 trees were then modeled and quantified using the open‐source software TreeQSM. As a result, “in silico” branching and biometric data for the young peach trees were calculated to demonstrate the capabilities of TLS phenotyping of peach tree‐crown architecture. The comparison and analysis of field measurements (in situ) and in silico BD, biometric data, and quantitative structural model branch uncertainty data were utilized to determine the reconstructive model's reliability as a source substitute for field measurements. Mean average deviation when comparing young tree (YT) height was approx. 5.93%, with crown volume was approx. 13.26% across both 2021 and 2022. All point clouds of the YTs in 2022 showed residuals lower than 12 mm to cylinders fitted to all branches, and mean surface coverage greater than 40% for both the trunk and primary branching orders.