Type Ia Research Articles

Endovascular Repair of Ruptured Abdominal Aortic Aneurysms Using the Endurant™ Endograft.

Background: Endovascular aortic aneurysm repair (EVAR) represents a valid treatment modality for ruptured abdominal aortic aneurysms (rAAAs). This study aimed to present rAAA outcomes treated by EVAR using the Endurant endograft. Methods: A single-center retrospective analysis of consecutive patients treated with standard EVAR (sEVAR) or parallel graft (PG)-EVAR for infra- or juxta/para-renal rAAA using the Endurant endograft (1 January 2008-31 December 2023) was undertaken. The primary outcomes were technical success, mortality, and reintervention. Follow-up outcomes, including survival and freedom from reintervention, were assessed using Kaplan-Meier estimates. Results: Eighty-eight patients were included (87.5% sEVAR and 12.5% PG-EVAR). The mean aneurysm diameter was 73.3 ± 19.3 mm (71.4 ± 22.2 mm sEVAR and 81.7 ± 33.0 mm PG-EVAR). Among 77 patients receiving sEVAR, 26 (33.8%) received an aorto-uni-iliac device. All PG-EVAR patients were managed with bifurcated devices, one receiving a single PG, seven double PGS, and three triple PGs. Technical success was 98.8% (100.0% sEVAR and 90.9% PG-EVAR). The 30-day mortality was 47.2% (50.7% sEVAR and 27.3% PG-EVAR), with nine (10.2%) deaths recorded on the table. The mean time of follow-up was 13 ± 9 months. After excluding 30-day deaths, the estimated survival was 75.5% (standard error (SE) 6.9%) at 24 months. The estimated freedom from reintervention was 89.7% (SE 5.7%) at 24 months. Only one endoleak type Ia event was recorded during follow-up. Conclusions: Endurant showed high technical success rates and low rates of endoleak type Ia events and reinterventions, despite the emergent setting of repair. rAAA is still a highly fatal condition within 30 days, with an acceptable mid-term survival of 30-day survivors at 75.5%.

Multi-iron subpopulations in Liller 1 from high-resolution H-band spectroscopy

We present a high-resolution chemical study of a representative sample of 21 luminous giant stars in Liller 1, a complex stellar system in the Galactic bulge, based on H-band spectra acquired with the Near-Infrared Spectrograph at KeckII. In this sample, we found fifteen stars with a subsolar iron abundance and enhanced alpha /Fe and Al/Fe likely older, having formed early and quickly from gas mainly enriched by type II supernovae, and six stars with supersolar iron and roughly solar-scaled alpha /Fe and Al/Fe likely younger, having formed at later epochs from gas also enriched by type Ia supernovae. Moreover, both subpopulations show enhanced N/Fe as in the bulge field, approximately solar-scaled V/Fe and depletion of C/Fe and 12C/13C with respect to the solar values, indicating the occurrence of significant mixing in the stellar interiors of these evolved stars. Our study also reveals that the subsolar subpopulation shows some structuring, and the presence of a third subcomponent with iron content and intermediate alpha /Fe enhancement, in between that of the metal-poor and metal-rich main subpopulations, has been statistically assessed, providing the chemical signature of both an extended star formation with multiple bursts and some self-enrichment.

On the Interpretation of Cosmic Acceleration

In relativity, the Newtonian concepts of velocity and acceleration are observer-dependent quantities that vary with the chosen frame of reference. It is well established that in the comoving frame, cosmic expansion is currently accelerating; however, in the rest frame, this expansion is actually decelerating. In this paper, we explore the implications of this distinction. The traditional measure of cosmic acceleration, denoted by q, is derived from the comoving frame and describes the acceleration of the scale factor a for a 3D space-like homogeneous sphere. We introduce a new parameter qE representing the acceleration experienced between observers within the light cone. By comparing qE to the traditional q using observational data from Type Ia supernovae (SN) and the radial clustering of galaxies and quasars (BAO)—including the latest results from DESI2024—our analysis demonstrates that qE aligns more closely with these data. The core argument of the paper is that Λ—regardless of its origin—creates an event horizon that divides the manifold into two causally disconnected regions analogous to conditions inside a black hole’s interior, thereby allowing for a rest-frame perspective qE in which cosmic expansion appears to be decelerating and the horizon acts like a friction term. Such a horizon suggests that the universe cannot maintain homogeneity outside. The observed cosmological constant Λ can then be interpreted not as a driver of new dark energy or a modification of gravity but as a boundary term exerting an attractive force, akin to a rubber band, resisting further expansion and preventing event horizon crossings. This interpretation calls for a reconsideration of current cosmological models and the assumptions underlying them.

[formula omitted]-Cosmological Boundary Flux Parameter

Efforts to explain the current accelerated expansion of the universe have prompted the investigation of different scenarios characterised by dark energy models. In this study, we explore an extended ωCBFP model, incorporating two commonly used parameterisations of ω(z) in terms of the redshift z: ω(z)=ω0 and ω(z)=ω0+ω1z/(1+z). In this context, the cosmological parameter Λ is directly linked to the dark matter component through a barotropic framework, where Λ acts as the source of ρcdm, characterised by a dimensionless constant λ, and directly dependent on Λω(z)CDM, which is fully defined by a specific ω(z) functional form. Through a statistical analysis, using late-time data of observational Hubble and type Ia Supernovae, we computed the joint best-fit value of the free parameters by means of the affine-invariant MCMC. On the one hand, the ω0CBFP instance shows an unexpected larger Ω0cdm contribution than the current Ω0Λ. Remarkably this outcome has not been previously reported (to our knowledge). On the other hand, in the ω0ω1CBFP example the dark energy component makes up nearly 60% of the total matter-energy at z=0, compared to just 36% for the cold dark matter contribution. This last result aligns more with the conventional ΛCDM model. In both instances there are unusual increases in Ωcdm(z) around z=1; however, these rises are offset by a decrease in Ωb(z).

Type Ia Supernovae Can Arise from the Detonations of Both Stars in a Double Degenerate Binary

The precise origin of Type Ia supernovae (SNe Ia) is unknown despite their value to numerous areas in astronomy. While it is a long-standing consensus that they arise from the explosion of a carbon/oxygen white dwarf, the exact progenitor configurations and explosion mechanisms that lead to SNe Ia are still debated. One popular theory is the double detonation, in which a helium layer, accreted from a binary companion, detonates on the surface of the primary star, leading to a converging shock-induced detonation of the underlying core. It has recently been seen in simulations that a helium-rich degenerate companion may undergo its own explosion triggered by the impact from the ejecta of the primary star. We show 2D simulations that approximate a white dwarf undergoing a double detonation, which triggers the explosion of the degenerate companion, leading to either a triple or quadruple detonation. We also present the first multidimensional radiative transfer results from the triple and quadruple detonation scenario. We find that within a range of mass configurations of the degenerate binary, the synthetic light curves and spectra of these events match observations as well as theoretical models of isolated double detonations do. Notably, double and quadruple detonations that are spectrally similar and reach the same peak brightnesses have drastically different ejecta masses and produce different amounts of Si- and Fe-group elements. Further understanding of this scenario is needed in order to determine if at least some observed SNe Ia actually originate from two stars exploding.

Galactic Chemical Evolution Models Favor an Extended Type Ia Supernova Delay-time Distribution

Type Ia supernovae (SNe Ia) produce most of the Fe-peak elements in the Universe and therefore are a crucial ingredient in galactic chemical evolution models. SNe Ia do not explode immediately after star formation, and the delay-time distribution (DTD) has not been definitively determined by supernova surveys or theoretical models. Because the DTD also affects the relationship among age, [Fe/H], and [α/Fe] in chemical evolution models, comparison with observations of stars in the Milky Way is an important consistency check for any proposed DTD. We implement several popular forms of the DTD in combination with multiple star formation histories for the Milky Way in multizone chemical evolution models that include radial stellar migration. We compare our predicted interstellar medium abundance tracks, stellar abundance distributions, and stellar age distributions to the final data release of the Apache Point Observatory Galactic Evolution Experiment. We find that the DTD has the largest effect on the [α/Fe] distribution: a DTD with more prompt SNe Ia produces a stellar abundance distribution that is skewed toward a lower [α/Fe] ratio. While the DTD alone cannot explain the observed bimodality in the [α/Fe] distribution, in combination with an appropriate star formation history it affects the goodness of fit between the predicted and observed high-α sequence. Our model results favor an extended DTD with fewer prompt SNe Ia than the fiducial t −1 power law.

Feasibility of contrast-enhanced ultrasound in the detection and classification of endoleaks after endovascular aneurysm repair.

Endoleaks are common complications after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA). Computed tomographic angiography (CTA)/digital subtraction angiography (DSA) is considered the gold standard for evaluating contrast-enhanced ultrasound (CEUS) accuracy in the detection and classification of endoleaks. In recent years, CEUS has been widely used in this field. This study aimed to analyze the accuracy of CEUS in the detection and classification of endoleaks after EVAR. The data of 98 patients who underwent abdominal aorta CEUS from November 2017 to September 2023 in the ultrasound (US) department of Beijing Hospital were retrospectively analyzed. All the patients underwent EVAR of AAA before CEUS and CTA/DSA, and had complete clinical data. The CEUS and CTA/DSA results were compared to detect endoleaks and categorize the specific types of endoleaks. Among the 98 patients, 74 were male and 24 were female. The patients had an average age of 74.8±9.8 years (range, 43-90 years). Among the 98 patients, 37 (37.8%) endoleaks were detected by CEUS, of which 8 were type Ia, 2 were type Ib, 15 were type II, 7 were type III, 2 were type IV, 2 were type Ia combined with type III, and 1 was type II combined with type III. In addition, among these 98 patients, 39 (39.8%) endoleaks were detected by CTA/DSA, of which 8 were type Ia, 3 were type Ib, 18 were type II, 6 were type III, 2 were type Ia combined with type III, 1 was type II combined with type III, and 1 was type Ib combined with type II. The sensitivity and specificity of CEUS in the detection of endoleaks were 92.3% and 98.3%, respectively. CEUS and CTA/DSA had similar diagnostic efficacy and good consistency in the detection and classification of endoleaks (Kappa value: 0.914, P<0.01). CEUS has high sensitivity and specificity in the detection and classification of endoleaks following EVAR, and its diagnostic efficacy is similar to that of CTA/DSA. In addition, US is safe, non-invasive and repeatable, and thus is worthy of extensive clinical application.

Shocking and Mass Loss of Compact Donor Stars in Type Ia Supernovae

Type Ia supernovae arise from thermonuclear explosions of white dwarfs accreting from a binary companion. Following the explosion, the surviving donor star leaves at roughly its orbital velocity. The discovery of the runaway helium subdwarf star US 708, and seven hypervelocity stars from Gaia data, all with spatial velocities ≳900 km s−1, strongly support a scenario in which the donor is a low-mass helium star or a white dwarf. Motivated by these discoveries, we perform three-dimensional hydrodynamical simulations with the Athena++ code, modeling the hydrodynamical interaction between a helium star or helium white dwarf and the supernova ejecta. We find that ≈0.01–0.02 M ⊙ of donor material is stripped, and explain the location of the stripped material within the expanding supernova ejecta. We continue the postexplosion evolution of the shocked donor stars with the MESA code. As a result of entropy deposition, they remain luminous and expanded for ≈105–106 yr. We show that the postexplosion properties of our helium white dwarf donor agree reasonably with one of the best-studied hypervelocity stars, D6-2.

The Pristine Inner Galaxy Survey (PIGS)

The most metal-poor stars provide valuable insights into the early chemical enrichment history of a system, carrying the chemical imprints of the first generations of supernovae. The most metal-poor region of the Sagittarius dwarf galaxy remains inadequately observed and characterised. To date, only ∼4 stars with [Fe/H] &lt; −2.0 have been chemically analysed with high-resolution spectroscopy. In this study, we present the most extensive chemical abundance analysis of 12 low-metallicity stars with metallicities down to [Fe/H] = −3.26 and located in the main body of Sagittarius. These targets, selected from the Pristine Inner Galaxy Survey, were observed using the MIKE high-resolution spectrograph at the Magellan-Clay telescope, which allowed us to measure up to 17 chemical species. The chemical composition of these stars reflects the imprint of a variety of type II supernovae (SNe II). A combination of low- to intermediate-mass high-energy SNe and hypernovae (∼10 − 70 M⊙) is required to account for the abundance patterns of the lighter elements up to the Fe-peak. The trend of the heavy elements suggests the involvement of compact binary merger events and fast-rotating (up to ∼300 km s−1) intermediate-mass to massive metal-poor stars (∼25 − 120 M⊙) that are the sources of rapid and slow processes, respectively. Additionally, asymptotic giant branch stars contribute to a wide dispersion of [Ba/Mg] and [Ba/Eu]. The absence of an α−knee in our data indicates that type Ia supernovae did not contribute in the very metal-poor region ([Fe/H] ≤ −2.0). However, they might have started to pollute the interstellar medium at [Fe/H] &gt; −2.0, given the relatively low [Co/Fe] in this metallicity region.

The Dark Energy Survey: Cosmology Results with ∼1500 New High-redshift Type Ia Supernovae Using the Full 5 yr Data Set

We present cosmological constraints from the sample of Type Ia supernovae (SNe Ia) discovered and measured during the full 5 yr of the Dark Energy Survey (DES) SN program. In contrast to most previous cosmological samples, in which SNe are classified based on their spectra, we classify the DES SNe using a machine learning algorithm applied to their light curves in four photometric bands. Spectroscopic redshifts are acquired from a dedicated follow-up survey of the host galaxies. After accounting for the likelihood of each SN being an SN Ia, we find 1635 DES SNe in the redshift range 0.10 < z < 1.13 that pass quality selection criteria sufficient to constrain cosmological parameters. This quintuples the number of high-quality z > 0.5 SNe compared to the previous leading compilation of Pantheon+ and results in the tightest cosmological constraints achieved by any SN data set to date. To derive cosmological constraints, we combine the DES SN data with a high-quality external low-redshift sample consisting of 194 SNe Ia spanning 0.025 < z < 0.10. Using SN data alone and including systematic uncertainties, we find ΩM = 0.352 ± 0.017 in flat ΛCDM. SN data alone now require acceleration (q 0 < 0 in ΛCDM) with over 5σ confidence. We find (ΩM,w)=(0.264−0.096+0.074,−0.80−0.16+0.14) in flat wCDM. For flat w 0 w a CDM, we find (ΩM,w0,wa)=(0.495−0.043+0.033,−0.36−0.30+0.36,−8.8−4.5+3.7) , consistent with a constant equation of state to within ∼2σ. Including Planck cosmic microwave background, Sloan Digital Sky Survey baryon acoustic oscillation, and DES 3 × 2pt data gives (ΩM, w) = (0.321 ± 0.007, −0.941 ± 0.026). In all cases, dark energy is consistent with a cosmological constant to within ∼2σ. Systematic errors on cosmological parameters are subdominant compared to statistical errors; these results thus pave the way for future photometrically classified SN analyses.

A possible late-time transition of M B inferred via neural networks

The strengthening of tensions in the cosmological parameters has led to reconsidering the fundamental aspects of standard cosmology. The tension in the Hubble constant can also be viewed as a tension between local and early Universe constraints on the absolute magnitude M B of Type Ia supernova. In this work, we reconsider the possibility of a variation of this parameter in a model-independent way. We employ neural networks to agnostically constrain the value of the absolute magnitude as well as assess the impact and statistical significance of a variation in M B with redshift from the Pantheon+ compilation, together with a thorough analysis of the neural network architecture. We find an indication for a possible transition redshift at the z ≈ 1 region.

Small Magellanic Cloud Cepheids Observed with the Hubble Space Telescope Provide a New Anchor for the SH0ES Distance Ladder

We present phase-corrected photometric measurements of 88 Cepheid variables in the core of the Small Magellanic Cloud (SMC), the first sample obtained with the Hubble Space Telescope's (HST) Wide Field Camera 3, in the same homogeneous photometric system as past measurements of all Cepheids on the SH0ES distance ladder. We limit the sample to the inner core and model the geometry to reduce errors in prior studies due to the nontrivial depth of this cloud. Without crowding present in ground-based studies, we obtain an unprecedentedly low dispersion of 0.102 mag for a period–luminosity (P–L) relation in the SMC, approaching the width of the Cepheid instability strip. The new geometric distance to 15 late-type detached eclipsing binaries in the SMC offers a rare opportunity to improve the foundation of the distance ladder, increasing the number of calibrating galaxies from three to four. With the SMC as the only anchor, we find H 0 = 74.1 ± 2.1 km s−1 Mpc−1. Combining these four geometric distances with our HST photometry of SMC Cepheids, we obtain H 0 = 73.17 ± 0.86 km s−1 Mpc−1. By including the SMC in the distance ladder, we also double the range where the metallicity ([Fe/H]) dependence of the Cepheid P–L relation can be calibrated, and we find γ = −0.234 ± 0.052 mag dex−1. Our local measurement of H 0 based on Cepheids and Type Ia supernovae shows a 5.8σ tension with the value inferred from the cosmic microwave background assuming a Lambda cold dark matter (ΛCDM) cosmology, reinforcing the possibility of physics beyond ΛCDM.

Teleparallel gravity and quintessence: The role of nonminimal boundary couplings

In this paper, we have outlined the development of an autonomous dynamical system within a general scalar-tensor gravity framework. This framework encompasses the overall structure of the non-minimally coupled scalar field functions for both the torsion scalar (T) and the boundary term (B). We have examined three well-motivated forms of potential functions and constrained the model parameters through dynamical system analysis. This analysis has played a crucial role in identifying cosmologically viable models. We have analysed the behaviour of dynamical parameters such as equation-of-state parameters, as well all the standard density parameters for radiation, matter, and dark energy to assess their compatibility with current observational data. The phase space diagrams are presented to support the stability conditions of the corresponding critical points. The Universe is apparent in its late-time cosmic acceleration phase via the dark energy-dominated critical points. Additionally, we compare our findings with the most prevailing ΛCDM model. The outcomes are further inspected using the cosmological data sets of Supernovae Ia and the Hubble rate H(z).

VE81 Leveraging urological robotic expertise in robot assisted aortic banding for type IA EVAR endoleak

VE81 Leveraging urological robotic expertise in robot assisted aortic banding for type IA EVAR endoleak

Early results from the pivotal trial substudy of the GORE EXCLUDER conformable endoprosthesis in angulated necks

ObjectiveTo report the investigational device exemption study 1-year clinical outcomes of the high neck angulation (HNA) substudy of the GORE EXCLUDER Conformable AAA Endoprosthesis (EXCC) for treatment of infrarenal abdominal aortic aneurysms (AAAs). MethodsThis study is a prospective, multicenter clinical trial conducted in the United States and included core laboratory assessment of imaging and independent event adjudication. Anatomical criteria for enrollment in the HNA substudy included infrarenal aortic neck angulation >60° and ≤90° with aortic neck length ≥10 mm. Primary safety end points included estimated blood loss of >1000 mL, death, stroke, myocardial infarction, bowel ischemia, paraplegia, respiratory failure, renal failure, and thromboembolic events. Primary effectiveness end points included technical success, absence from type I and III endoleaks, migration (≥10 mm), sac enlargement (≥5 mm), sac rupture, and conversion to open repair. ResultsBetween January 2018 and February 2022, 95 patients were enrolled in the HNA substudy across 35 sites. Of the 95 patients, 71 (74.7%) were male and the cohort average age was 74.4 years. The mean infrarenal proximal aortic neck angle was 71.6° and the mean AAA size was 62.9 mm. Overall technical success was achieved in 93 patients (97.9%). Freedom from a primary safety end point through 30 days was 96.7%; 3 (3.3%) patients had an estimated blood loss of >1000 mL. Freedom from the primary effectiveness at 12 months was achieved in 94.8%. Four patients (4.3%) had a type IA endoleak; intervention after the procedure was not required and no subsequent interventions or sac enlargement were noted in these patients. At 12 months, 29 patients (39.7%) experienced a type II endoleak and 1 (1.3%) patient experienced AAA sac expansion of ≥5 mm. Through 12 months, 1 patient (1.3%) had a conversion to open surgical repair. There were no aneurysm-related deaths, ruptures, or migration through 12 months. ConclusionsThe investigational device exemption study demonstrates safety and effectiveness of the GORE EXCLUDER Conformable AAA Endoprosthesis device in AAA with highly angulated necks (>60° and ≤90°) are preserved at the 12-month follow-up.

Adiabatic Mass Loss in Binary Stars. IV. Low- and Intermediate-mass Helium Binary Stars

The unstable mass transfer situation in binary systems will asymptotically cause the adiabatic expansion of the donor star and finally lead to the common envelope phase. This process could happen in helium binary systems once the helium donor star fills its Roche-lobe. We have calculated the adiabatic mass-loss model of naked helium stars with a mass range of 0.35 M ⊙–10 M ⊙, and every mass sequence evolved from the helium-zero-age main sequence to the cooling track of white dwarf or carbon ignition. In consideration of the influence of stellar wind, massive helium stars are not considered in this paper. Comparing the stellar radius with the evolution of the Roche-lobe under the assumption of conservative mass transfer, we give the critical mass ratio q crit = M He/M accretor as the binary stability criteria of low- and intermediate-mass helium binary stars. On the helium main sequence, the result shows 1.0 < q crit < 2.6, which is more unstable than the classical result of polytropic model q crit = 3. After the early helium Hertzsprung Gap, the q crit quickly increases even larger than 10 (more stable compared with the widely used result of q crit = 4), which is dominated by the expansion of the radiative envelope. Our result could be useful for these quick mass transfer binary systems such as AM CVns, ultra-compact X-ray binaries, and helium novae, and it could guide the binary population synthesis for the formation of special objects such as type Ia supernova and gravitational wave sources.

Origin of the Strong Sodium Absorption of the Lensed Supernova 2016geu at z = 0.4

The origin of strong sodium absorption, which has been observed for a few nearby Type Ia supernovae (SNe Ia), remains elusive. Here we analyze two high-signal-to-noise, intermediate-resolution Very Large Telescope/X-shooter spectra at epochs +18 and +27 days past peak brightness of the strongly lensed and multiply imaged Type Ia SN 2016geu, which exploded at a redshift of z = 0.4. We show that SN 2016geu exhibits very strong multiple Na i and Ca ii absorption lines with a large total Na i D rest-frame equivalent width (EW) of 5.2 ± 0.2 Å, among the highest ever detected for an SN Ia and similar to only a handful of nearby SNe Ia with extraordinarily large Na i D EWs. The absorption system is time-invariant and extends over a large velocity span ∼250 km s−1. The majority of the absorption is blueshifted relative to the strongest component, while there are both blueshifted and redshifted components relative to the systemic redshift of the galaxy. The column density ratios and widths of the absorption lines indicate that the absorption likely arises from a combination of interstellar dusty molecular clouds and circumgalactic in- and outflowing material rather than circumstellar matter around the supernova.

Unveiling the Hubble constant through galaxy cluster gas mass fractions

In this work, we obtain Hubble constant (H0) estimates by using two galaxy cluster gas mass fraction measurement samples, Type Ia supernovae luminosity distances, and the validity of the cosmic distance duality relation. Notably, the angular diameter distance (ADD) to each galaxy cluster in the samples is determined by combining its gas mass fraction measurement with galaxy clustering observations, more precisely, the Ωb/Ωm ratio. Such a combination results in a H0 estimate that is independent of a specific cosmological framework. In one of the samples, the gas fraction measurements were calculated in spherical shells at radii near r2500 (44 data points), while in the other (103 data points) the measurements were calculated within r500. We find H0=72.7−5.6+6.3 km/s/Mpc at 68% CL for the joint analysis of these data sets. We also investigate the impact on the H0 determination by exploring the precision and number of gas mass fraction data by performing a data Monte Carlo simulation. Our simulations show that future measurements could achieve a precision of up to 5% for H0.

Prognostic Prediction of Multiterritory Flap: A Preliminary Clinical Study on the Classification of Priority Developing Artery and Arterial Anastomosis Utilizing Indocyanine Green Angiography.

Congestion and necrosis are frequent complications in multiterritory flaps. Indocyanine green angiography (ICGA) is a commonly utilized tool for evaluating blood flow and perforator location within the flap; however, there is currently no existing research investigating its potential to predict flap prognosis before surgery. The forehead skin of 50 surgical patients was assessed using preoperative ICGA, enabling observation and classification of the priority developing artery and arterial anastomosis among adjacent arterial perfusion territories during the arterial phase. Subsequently, 5 clinical cases of forehead flap transfer were studied to validate the classification method. First, the priority developing artery can be classified into 4 types and 5 subtypes, encompassing type Ⅰa: Bilateral ST-As equalization type (9/50), type Ⅰb: unilateral ST-A dominance type (11/50), type II: SOT-As dominance type (14/50), type III: unilateral ST-A plus SOT-A dominance type (6/50), and type IV: bilateral ST-As plus SOT-As equilibrium type (10/50). Second, arterial anastomosis can be divided into 5 types: type I: complete choke anastomosis type (13/50), type II: complete true anastomosis type (7/50), type III: central choke anastomosis type (10/50), type IV: bilateral choke anastomosis type (8/50), and type V: unilateral choke anastomosis type (12/50). Finally, the clinical flap outcomes showed that the ICGA classification could serve as a good prognostic indicator. The hemodynamic classification of priority developing artery and arterial anastomosis employed by ICGA has the potential to predict flap prognosis and offer valuable insights for preoperative design and perioperative treatment strategies. More sample size is needed to optimize and validate this classification.

Carotid Plexus Sympathetic Nerves as a Landmark for the Abducens Nerve Within the Cavernous Sinus During Endoscopic Endonasal Surgery: Cadaveric Anatomic Study and Surgical Consideration.

The abducens nerve (CN VI) is vulnerable to injury during endoscopic endonasal transcavernous surgery. In this study, the authors aimed to develop the surgical anatomic landmark and explore the relationship between the sympathetic nerves (SNs) around the internal carotid artery (ICA) and CN VI within the cavernous sinus (CS). The relationship and patterns between the SNs and CN VI were investigated in 15 cadaveric specimens. The intraoperative examples of anatomic landmark were presented. There were SNs around the ICA running into the CN VI, classified into ascending SNs and accessory sympathetic branches. The ascending SNs were divided into 3 types: (1) Type I had a single ascending SN. There were 2 subtypes of Type I (Type IA [17/30, 56.7%] was defined as a single ascending branch that ran into the CN VI, and Type IB [4/30, 13.3%] was defined as a single ascending branch with a terminal bifurcation before merging into the CN VI or lateral CS wall), (2) Type II (7/30, 23.3%) was defined as 2 ascending branches that ran into the CN VI and the lateral CS wall, and (3) Type III (2/30, 6.7%) was defined as 3 ascending branches that ran into the CN VIs and the lateral wall of the CS. The accessory branches of the SNs were defined by sympathetic branches from the posterior genu or horizontal ICA and found in 6/30 sides (20%). The authors propose a classification of the relationship between paraclival ICA SNs and the CN VI within the CS, as approached during endoscopic endonasal surgery. The consistent relationship of the ascending SN and CN VI within the CS provides a reliable anatomic landmark during the endonasal approach to the CS.