Composition of encephalic arteries and origin of the basilar artery are different between vertebrates.

Intracranial arterial anatomy is lacking for most mammalian and non-mammalian model species, especially concerning the origin of the basilar artery (BA). Enhancing the knowledge of this anatomy can improve animal models and help understanding anatomical variations in humans. We have studied encephalic arteries in three different species of birds and eight different species of mammals using formalin-fixed brains injected with arterial red latex. Our results and literature analysis indicate that, for all vertebrates, the internal carotid artery (ICA) supplies the brain and divides into two branches: a cranial and a caudal branch. The difference between vertebrates lies in the caudal branch of the ICA. For non-mammalian, the caudal branch is the origin of the BA, and the vertebral artery (VA) is not involved in brain supply. For mammals, the VA supplies encephalic arteries in two different ways. In the first type of organization, mostly found in ungulates, the carotid rete mirabile supplies the encephalic arteries, the caudal branch is the origin of the BA, and the VA is indirectly involved in carotid rete mirabile blood supply. The second type of encephalic artery organization for mammals is the same as in humans. The caudal branch of the ICA serves as the posterior communicating artery, and the BA originates from both VAs. We believe that knowledge of comparative anatomy of encephalic arteries contributes to a better understanding of animal models applicable to surgical or radiological techniques. It improves the understanding of rare encephalic variations that may be present in humans.

The carotid and vertebral arteries discovery ­ initial findings / A descoberta das artérias carótidas e vertebrais ­ achados iniciais

The studies on the vascular system, including the cervicocephalic arteries (carotid and vertebral arteries), present a long trajectory, having their deep roots in the far past, considering the Western authors, having as representatives the Greek sages Alcmaeon, Diogenes, Hippocrates, Aristoteles, Rufus, and Galenus. They produced pivotal knowledge dissecting mainly cadavers of animals, and established solid bases for the later generations of scholars. The information assembled from these six authors makes it possible to build a quite clear picture of the vascular system, here specifically focused on the cervicocephalic arteries, and mainly of the extracranial segments. Thus, the carotid system became fairly well identified, origin, course, and name, as well as the origin of the still unnamed arteries running through the orifices of the transversal processes of the cervical vertebrae, and entering into the cranium. Almost all that was then known about human anatomy, since this period, and then throughout the Middle Ages, was extrapolated from animal dissections. This state of affairs was maintained until the 14th century, when human corpses dissections were again allowed.

Os estudos do sistema vascular, incluindo as artérias cervicocefálicas (artérias carótidas e vertebrais), apresentam um longo percurso, tendo suas raízes profundas no passado distante, considerando os autores ocidentais, tendo como representantes os doutos gregos Alcméon, Diógenes, Hipócrates, Aristóteles, Rufus e Galenus. Eles produziram conhecimento pivotal, dissecando principalmente cadáveres de animais e estabelecendo bases sólidas para as gerações futuras de estudiosos. A informação reunida desses seis autores permite construir um quadro bastante claro do sistema vascular, aqui focado especificamente nas artérias cervicocefálicas e principalmente nos seus segmentos extracranianos. Assim, o sistema carotídeo ficou bastante bem identificado, origem, trajeto e nome, assim como a origem das ainda não nomeadas artérias que percorrem os orifícios dos processos transversos das vértebras cervicais e entrando no crânio. Quase tudo que era conhecido sobre anatomia humana, desde esse período, e depois ao longo da Idade Média, foi extrapolado a partir de dissecções de animais. Esse estado de coisas foi mantido até o século 14, quando a dissecção de cadáveres humanos foi novamente permitida.

Quantitative Prediction of the Location of Carotid Bifurcation and Neurovascular Structures in the Carotid Region: A Cross-Sectional Cadaveric Study.

INTRODUCTION: The carotid region is encountered in vascular and neurological surgery and carries a potential for vascular and cranial nerve trauma. The carotid bifurcation is an especially important landmark and difficult to predict based on currently established landmarks. This study is a detailed analysis of the carotid region and proposes a novel methodology to predict the height of the bifurcation. MATERIALS AND METHODS: Superficial and deep dissections were performed on the anterior triangle of the neck to expose the carotid region in twenty-one formalin-fixed donor cadavers. Musculoskeletal and neurovascular structures were assessed in relation to the carotid bifurcation and the medial border of the clavicle (MBC). RESULTS: The carotid bifurcation occurred, on average, 11.4 mm higher on the left (p < 0.001; 95% CI: 9.28, 13.54). The superior thyroid artery (p < 0.001), facial vein (p < 0.001), and cranial nerve XII (p < 0.001) were all more distal on the left side when measured from the MBC while the angle of the mandible and stylohyoid muscle remained symmetric. Left- and right-sided vascular structures were symmetric when measured from the carotid bifurcation. CONCLUSIONS: Neurovascular structures within the carotid region are likely to be anatomically superior on the left side while vessels are likely to remain symmetric in relation to the carotid bifurcation. When measured from the MBC, the bifurcation height can be predicted by multiplying the distance between the MBC and mastoid process by 0.65 (right side) or 0.74 (left side). This novel methodological estimation may be easily learned and directly implemented in clinical practice.

Anatomical description and variations of the anterior arterial brain circulation in Colombian cadaveric specimens / Descripción anatómica y variaciones de la circulación cerebral arterial anterior en especímenes cadavéricos colombianos

SUMMARY: Understanding microsurgical neuroanatomy is a fundamental part of the training of neurosurgeons. Notwithstanding the fact that throughout history the study in cadavers has been a fundamental part of training, the publication of these studies has never marked a trend, and in our country the available studies are limited. A descriptive anatomical study was carried out on 22 specimens regarding the anatomical arrangement of the anterior circulation arteries of the brain and the most frequent anatomical variants in the sample used. To this end, bilateral pterional and bifrontal approaches were performed, obtaining a total of 132 arteries, including supraclinoid internal carotid arteries (ICA), anterior cerebral arteries in their A1 segment (ACA), and middle cerebral arteries in their M1 segment (MCA). measurements in each of these segments were made and anatomical variants were documented. Out of 22 cadaveric specimens, 17 (77 %) were male. the mean age was 59 years (range 36-81 years). Internal carotid artery mean length was 12.73 and 12.86 in the right and left side respectively. Anatomical variants identified were hypoplasia of segment A1 in 1 (4.5 %) specimen, duplication in 1 (4.5 %) and trifurcation of segment M1 in 3 (13.6 %) specimens. A similarity was found between our data and data reported by literature, with some differences, especially in the anterior communicating artery.

RESUMEN: Entender la neuroanatomía microquirúrgica es una parte fundamental de la formación de los neurocirujanos. A pesar de que, durante la historia, el estudio en cadáveres ha sido parte fundamental del entrenamiento, no ha sido tendencia la publicación de estos estudios, y en nuestro país son limitados los que se encuentran. Se realizó un estudio descriptivo anatómico en 22 especímenes acerca de la disposición anatómica de las arterias de la circulación cerebral anterior y las variantes anatómicas más frecuentes en población colombiana. Para dicho objetivo se realizaron abordajes bilaterales pterionales, y bifrontales obteniendo un total de 132 arterias incluyendo las arterias carotídeas internas supraclinoideas (ACI), arterias cerebrales anteriores en su segmento A1 (ACA) y las arterias cerebrales medias en su segmento M1 (ACM), se realizaron mediciones en cada uno de estos segmentos y se documentaron las variantes anatómicas. De los 22 especímenes cadavéricos, 17 (77 %) eran masculinos, la edad media fue de 59 años (rango 36-81 años). La longitud media de la arteria carótida interna fue de 12,73 mm en el lado derecho y de 12,86 mm en el lado izquierdo. Las variantes anatómicas identificadas fueron hipoplasia del segmento A1 en 1 (4,5 %), duplicación de A1 en 1 (4,5 %) y trifurcación del segmento M1 en 3 (13,6 %) muestras. Se encontró una similitud entre nuestros datos y los reportados por la literatura, con algunas diferencias, especialmente en el segmento de la arteria comunicante anterior.

The carotid axis revisited.

The aim was to determine the variations in the level of origin of carotid bifurcation and diameters of the common, internal, and external carotid arteries which is clinically important for several interventional procedures. Therefore, 165 human embalmed corpses were dissected. The data collected were analyzed using the Chi square-test and the Pearson correlation test. The results of previous studies have been reviewed. In relation to the level of the carotid bifurcation, taking as a reference point the hyoid bone, the values ranged from 4 cm below the hyoid body to 2.5 cm above the body of the hyoid, being the average height-0.33 cm, with a standard deviation of 1.19 cm. The right carotid bifurcation was established at a higher level (x = - 0.19 cm.) than the left one (x = - 0.48 cm.) (p = 0.046). On the contrary, no significant gender differences could be observed. The arterial calibres of the common and internal carotid arteries were higher in male than female. In the internal carotid artery (X = 0.76 cm.), the left was greater than the right (X = 0.72 cm.) (P = 0.047). However, no differences in the distribution of the calibre of the external carotid artery were found neither by side nor gender. Variations in the level of bifurcation and calibres of carotid arteries are relevant for interventional radiology procedures and head and neck surgeries. Knowledge of these anatomical references might help clinicians in the interpretation of the carotid system.

Inner diameters of the normal carotid arteries measured using three-dimensional digital subtraction catheter angiography: a retrospective analysis.

PURPOSE: To obtain normal ranges for the inner diameters of the carotid arteries. METHODS: This retrospective analysis included consecutive patients with disease-free carotid arteries who had undergone 3D-DSA at two hospitals in Nanning, Guangxi, between March 2013 and March 2018. Demographic and clinical characteristics, including Essen Stroke Risk Score (ESRS), were extracted from the medical records. The 3D-DSA data were used to calculate the inner diameters of the carotid arteries. RESULTS: The analysis included 1182 patients (837 males) aged 58.81 ± 11.02 years. The inner diameters of the proximal carotid sinus (CS), CS bulge, distal CS, and common carotid artery (CCA) were larger on the right than on the left (P < 0.05). The inner diameters of the proximal CS, CS bulge, distal CS, and CCA on both sides were larger for males than females (P < 0.05). The inner diameters of the proximal CS, CS bulge, and distal CS on both sides were smaller for patients aged > 65 years than for patients aged ≤ 55 years (P < 0.05). Right CCA inner diameter did not vary with age, whereas left CCA inner diameter was larger for patients aged > 55 years than for patients aged ≤ 45 years (P < 0.05). The inner diameters of the proximal CS, CS bulge, and distal CS on both sides were smaller for patients with ESRS ≥ 3 than those with ESRS < 3 (P < 0.05). CONCLUSION: This study provides reference values for the internal diameters of normal carotid arteries. Carotid artery diameters varied with side, sex, and age.

Radiological evaluation of the localization of sympathetic ganglia in the cervical region.

PURPOSE: To determine local variations of cervical sympathetic ganglia (CSG) according to vertebral levels on preoperative neck magnetic resonance imaging (MRI) by designating carotid artery (CA) as the standard landmark at the center, in attempts to prevent injury to CSG in the anterior-anterolateral approaches performed in the cervical spinal region. MATERIALS AND METHODS: The retrospective study reviewed neck MRI images of 281 patients, of which the images of 231 patients were excluded from the study based on the exclusion criteria. As a result, the MRI images of the remaining 50 patients were included in the study. The circumference of carotid artery (CA) was divided into eight equal zones with CA defined as the standard landmark at the center. High-risk zones were determined based on the anterior-anterolateral approaches. RESULTS: At C1 level, a superior ganglion was located on the right side in 32 (64%) and on the left side in 30 (60%) patients. At this level, it was most commonly located in Zone 6. Middle ganglion was observed most frequently at C3 level, which was detected on the right side in 17 (34%) and on the left side in 17 (34%) patients. At this level, it was most commonly located in Zone 2. CONCLUSION: Variations in the localizations of superior and middle cervical ganglia should be taken into consideration prior to surgical procedures planned for this region. This study sheds light on high-risk zones in the surgical site and could guide surgeons to better understand the location of cervical sympathetic ganglia before surgical planning.

Automated segmentation of the individual branches of the carotid arteries in contrast-enhanced MR angiography using DeepMedic.

BACKGROUND: Non-invasive imaging is of interest for tracking the progression of atherosclerosis in the carotid bifurcation, and segmenting this region into its constituent branch arteries is necessary for analyses. The purpose of this study was to validate and demonstrate a method for segmenting the carotid bifurcation into the common, internal, and external carotid arteries (CCA, ICA, ECA) in contrast-enhanced MR angiography (CE-MRA) data. METHODS: A segmentation pipeline utilizing a convolutional neural network (DeepMedic) was tailored and trained for multi-class segmentation of the carotid arteries in CE-MRA data from the Swedish CardioPulmonsary bioImage Study (SCAPIS). Segmentation quality was quantitatively assessed using the Dice similarity coefficient (DSC), Matthews Correlation Coefficient (MCC), F2, F0.5, and True Positive Ratio (TPR). Segmentations were also assessed qualitatively, by three observers using visual inspection. Finally, geometric descriptions of the carotid bifurcations were generated for each subject to demonstrate the utility of the proposed segmentation method. RESULTS: Branch-level segmentations scored DSC = 0.80 ± 0.13, MCC = 0.80 ± 0.12, F2 = 0.82 ± 0.14, F0.5 = 0.78 ± 0.13, and TPR = 0.84 ± 0.16, on average in a testing cohort of 46 carotid bifurcations. Qualitatively, 61% of segmentations were judged to be usable for analyses without adjustments in a cohort of 336 carotid bifurcations without ground-truth. Carotid artery geometry showed wide variation within the whole cohort, with CCA diameter 8.6 ± 1.1 mm, ICA 7.5 ± 1.4 mm, ECA 5.7 ± 1.0 mm and bifurcation angle 41 ± 21°. CONCLUSION: The proposed segmentation method automatically generates branch-level segmentations of the carotid arteries that are suitable for use in further analyses and help enable large-cohort investigations.

Tomography of the Forehead Arteries and Tailored Filler Injection for Forehead Volumizing and Contouring.

BACKGROUND: The forehead is a challenging area for filler injection because of the risk of serious complications. Anatomy-based filler injection techniques help to avoid severe vascular complications. MATERIALS AND METHODS: Sixty-six cadaver heads were infused with adequate lead oxide contrast through the external carotid arteries, internal carotid arteries, facial artery, and superficial temporal artery. Three-dimensional computed tomography scans were reconstructed using validated algorithms. We measured the length and arc length of "beautiful" foreheads evaluated by 3 skilled surgeons. RESULTS: The frontal branch of the superficial temporal artery (FBSTA) was classified based on the main trunk as follows: Type I FBSTA (89.72%) took a sudden turn (89.56° ± 11.76°) once passing through the temporal crest, whereas Type II FBSTA (10.28%) barely turned (52.26° ± 6.81°) at the temporal crest. A total of 319 arteries passed through the midline in 48 cadaver heads. There were more superficial arteries (292 of 319) than deep arteries (27 of 319). The difference in the length and arc length of the forehead was 19.66 ± 4.35 mm. CONCLUSION: This study introduces an effective technique for forehead filler injection that minimizes the risk of filler injection and improves patient satisfaction.

Variant facial artery anatomy revisited: Conventional angiography performed in 284 cases.

A number of studies have evaluated the variable courses of facial artery. However, the results of these differed substantially from each other so not consistent relationships have yet been established. There has also yet to be a relevant study using conventional angiography.We assessed the variant branching pattern of the facial artery and its branches using conventional angiography.Two radiologists retrospectively reviewed 284 cases of angiographies of the external carotid artery in 198 patients. The courses of the facial artery and infraorbital branch of the maxillary artery were classified into 4 types and 2 types, according to the end branch.Among 284 cases of facial artery, type 1 (angular branch) made up 104 cases (36.6%), type 2 (lateral nasal branch) made up 138 cases (48.6%), type 3 (superior labial branch) made up 24 cases (8.5%), and type 4 (inferior labial branch) made up 18 cases (6.3%).Regarding the 284 total cases of maxillary artery, 163 cases (57.4%) had anastomosis with the angular artery or extended to the territory of the angular artery. In addition, 121 cases (42.6%) had nothing done in regard to the angular artery.The results may be helpful for avoiding complications related to facial and maxillary arteries during facial surgeries and cosmetic procedures.

Comparison of right and left common carotid arteries of horses and mules by two-dimensional ultrasound and Doppler flow / Comparação das artérias carótidas comuns direita e esquerda dos gêneros de equinos e muares por ultrassonografia bidimensional e Dopplerfluxométrico

In ultrasonography, the bi-dimensional mode (B-mode) allows the morphological and morphometric evaluation of several types of organs and tissues, while the Doppler mode allows the hemodynamic evaluation. In humans, the Doppler evaluation is routinely used in the assessment of important arteries and veins, such as the carotid arteries and jugular veins, with significant differences between genres and sides. However, in veterinary medicine, this diagnostic method is not yet well established in the evaluation of the carotid arteries, with only few reports in domestic horses. This study aims to compare the right and left common carotid arteries of domestic horses and mules using bi-dimensional and Doppler ultrasound evaluation. The common carotid arteries from 10 domestic horses (five males and five females) and 10 mules (five males and five females) were evaluated. The following variables were measured at three different portions (cranial, middle and caudal): diameter, intima-media thickness (IMT), resistivity index (RI), pulsatility index (PI), peak of systolic velocity (pSV) and final diastolic velocity (fDV). No significant differences were observed in the bi-dimensional variables (diameter and IMT) between the common carotid arteries of horses and mules, regardless of gender (p>0.05). In Doppler mode, there were no significant differences between carotid values in male and female horses (p> 0.05). In the mules, it was only possible to observe differences between the RI and PI values (p<0.05), being higher on the left side (0.81 and 2.04 respectively), and the fDV (p<0.05) higher, on the right side (14.35) in males. As for females, there was only in fDV (p<0.05), with the upper right side (23.16). Diameters and IMT do not differ between sides in horses and mules in B-mode ultrasound. Spectral Doppler in horses does not differ between sides, regardless of gender. As for mules, males differ in RI, PI and fDV between sides, while females differ only in fDV.(AU)

Na ultrassonografia, o modo bidimensional (modo B) permite a avaliação morfológica e morfométrica de vários tipos de órgãos e tecidos, enquanto o modo Doppler permite a avaliação hemodinâmica. Em humanos, a avaliação com Doppler é usada rotineiramente na avaliação de artérias e veias importantes, como as artérias carótidas e veias jugulares, com diferenças significativas entre gêneros e lados. No entanto, em medicina veterinária, este método diagnóstico ainda não está bem estabelecido na avaliação das artérias carótidas, com apenas poucos relatos em equinos domésticos. Este estudo tem como objetivo comparar as artérias carótidas comuns direita e esquerda de equinos e mulas domésticos, utilizando a avaliação bidimensional (modo B) e por ultrassonografia Doppler espectral. Avaliaram-se as artérias carótidas comuns de 10 equinos domésticos (cinco machos e cinco fêmeas) e 10 mulas (cinco machos e cinco fêmeas). As seguintes variáveis foram medidas em três porções diferentes (cranial, médio e caudal): diâmetro, espessura íntima-média (IMT), índice de resistividade (RI), índice de pulsatilidade (PI), pico de velocidade sistólica (pSV) e velocidade diastólica final (fDV). Não foram observadas diferenças significativas nas variáveis bidimensionais (diâmetro e IMT) entre as artérias carótidas comuns de cavalos e muares, independentemente do gênero (p>0,05). No modo Doppler, não houve diferenças significativas entre os valores para carótidas em equinos machos e fêmeas (p>0,05). Nos muares, só foi possível observar diferenças entre os valores de RI e PI (p<0,05), sendo maiores no lado esquerdo (0,81 e 2,04 respectivamente), e o fDV (p<0,05) superior no lado direito (14,35) nos machos. Quanto as fêmeas, houve apenas no fDV (p<0,05), sendo o lado direito superior (23,16). Os diâmetros e IMT não diferem entre os lados em equinos e muares na ultrassonografia modo B. Já o Doppler espectral nos equinos não difere entre os lados, independentemente do gênero. Quanto aos muares, os machos diferenciam no IR, IP e fDV entre os lados, enquanto as fêmeas apenas para fDV.(AU)

The anatomic variations and surgical windows among optic chiasm/nerves and carotid arteries in the sellar region play a role in choosing the best surgical approaches: A Cadaveric study / Las variaciones anatómicas y las vías de acceso quirúrgico en el quiasma, los nervios ópticos y las arterias carótidas de la región selar influyen en la elección de los mejores abordajes quirúrgicos: un estudio en cadáveres

OBJECTIVE: Understanding the relationship between the carotid artery, optic nerve and the anterior clinoid process is the basis of surgical approaches performed in the subchiasmal region. The location of the optic chiasm, the length of the optic nerves, and the distance and angle between the optic nerves determine the route of surgical approaches. We have determined the types of optic chiasm to study the relationship between vascular and neural structures in this region. MATERIALS AND METHODS: Thirty autopsy specimens were investigated at the Bursa Forensic Medicine Institute for optic chiasm types and the relationship between the neural and vascular anatomical structures of the sellar-parasellar and subchiasmal region was examined between June 2016 and November 2016. RESULTS: In this study, 4 prefix types (13%), 6 postfix types (20%), and 20 central types (67%) of chiasm were defined. Furthermore, we measured this angle between two optic nerves, which indirectly shows the location of chiasm according to the diaphragma sellae, and then detected the mean value of this angle as 87.1 ± 11.6°. The "limit" value to designate a chiasm as prefix was measured in the current study as ≥ 101.1°. The angle between optic nerves ranged from a mean value of 69.9 ± 3.7° in 6 cases with postfix chiasm, to a mean value of 104.0±2.1° in 4 cases with prefix chiasm and a mean value of 88.8 ± 6.7° in 20 cases with central chiasm. CONCLUSIÓN: In this study, we showed that the relationship among optic chiasma types, optic nerves and bony and vascular structures around the sellar area was effective at determining the surgical approach to this región

OBJETIVO: Comprender la relación entre la arteria carótida, el nervio óptico y la apófisis clinoides anterior es la base de los tratamientos quirúrgicos realizados en la región subquiasmática. La ubicación del quiasma óptico, la longitud de los nervios ópticos, y la distancia y el ángulo entre dichos nervios determinan la vía de acceso quirúrgico. Hemos determinado los tipos de quiasma óptico para estudiar la relación entre las estructuras vasculares y neurales en esta región. MATERIALES Y MÉTODOS: Entre junio y noviembre de 2016, se analizaron 30 muestras de autopsia en el Instituto de Medicina Legal de Bursa (Turquía) para determinar los tipos de quiasma óptico, y examinar la relación entre las estructuras anatómicas neurales y vasculares de las regiones selar-paraselar y subquiasmática. RESULTADOS: En este estudio, se definieron 4 casos de quiasma prefijado (13%), 6 de quiasma posfijado (20%) y 20 de quiasma central (67%). Además, medimos el ángulo entre 2 nervios ópticos que muestra indirectamente la ubicación del quiasma según el diafragma selar, y luego detectamos el valor medio de este ángulo (87,1 ± 11,6°). El valor «límite» para designar un quiasma como «prefijado» se midió en el estudio actual como ≥ 101,1°. El valor medio del ángulo entre los nervios ópticos osciló entre 69,9 ± 3,7° en los 6 casos de quiasma posfijado, 104,0 ± 2,1° en los 4 casos de quiasma prefijado y 88,8 ± 6,7° en los 20 casos de quiasma central. CONCLUSIÓN: En este estudio, pusimos de manifiesto que la relación entre los tipos de quiasma óptico, los nervios ópticos y las estructuras óseas y vasculares alrededor del área selar fue eficaz para determinar el acceso quirúrgico en esta región

Age and anatomical location related hemodynamic changes assessed by 4D flow MRI in the carotid arteries of healthy adults.

PURPOSE: To evaluate hemodynamic changes (volume, velocity, wall shear stress, pressure gradient, and energy loss) in the common carotid artery (CCA) and internal carotid artery (ICA) of healthy adults among different ages and anatomical locations using 4D flow MRI. METHODS: Sixty-two healthy volunteers aged 20-75 years were enrolled in this study. 4D flow MRI examinations were performed for each subject and were analyzed using the CVI42 platform to generate hemodynamic parameters. Hemodynamic parameters were compared among different age groups and anatomical locations (proximal CCA, distal CCA, proximal ICA and distal CCA) using one-way ANOVA. The paired t-test was used to estimate the differences between left and right vessels. The relationship between age and hemodynamic parameters was quantified by Pearson's correlation coefficient. RESULTS: There were no differences between the left and right carotid arteries for any of the hemodynamic parameters (all p values > 0.05), so we set each vessel as an independent sample. The proximal ICA had significantly lower volume, velocity, wall shear stress, and pressure gradient values than the values determined for other locations (p < 0.05), and energy loss was similar among different locations. Wall shear stress (except in the distal ICA), velocity, pressure gradient, and energy loss decreased with age (p < 0.05). CONCLUSIONS: The multiparameter analysis of 4D flow MRI can identify age and anatomical location changes in hemodynamic parameters in the carotid arteries of healthy adults. The lower velocity, wall shear stress, and pressure gradient in the proximal ICA and the reduced trend with age may be associated with disease occurrence.

Establishing reference values for macro- and microvascular measurements in 4-to-5 year-old children of the ENVIRONAGE prospective birth cohort.

Cardiovascular risk factors are usually better tolerated, and can therefore be perceived as less harmful, at a young age. However, over time the effects of these adverse factors may persist or accumulate and lead to excess morbidity and mortality from cardiovascular diseases later in life. Until now, reference values for the basic cardiovascular health characteristics of 4-to-6 year-old children are lacking. Within a follow-up study of the ENVIRONAGE (ENVIRonmental influence ON early AGE) birth cohort we assessed various cardiovascular measurements in 288 children aged 4-5 years. For the macrovasculature, we measured their blood pressure and examined the intima-media thickness of the carotid artery (CIMT), the arterial elasticity (including the pulse-wave velocity (PWV), carotid distensibility (DC) and compliance (CC) coefficients), the carotid ß stiffness index (SIß) and Young's Elastic Modulus (YEM). Retinal microvascular traits included the Central Retinal Arteriolar Equivalent (CRAE) and Central Retinal Venular Equivalent (CRVE). Age of the study population averaged (±SD) 4.2 (±0.4 years. Mean systolic and diastolic blood pressure were 97.9 (±8.1) mmHg and 54.7(±7.6) mmHg, respectively. CIMT for the total population averaged 487.1 (±68.1) µm. The average stiffness values for DC, CC, SIß, and PWV were 78.7 (±34.2) 10-³/kPa, 1.61 (±0.59) mm2/kPa and 4.4 (±2.4), and 3.7 m/s (±0.9) respectively. The mean determined for YEM was 163.2 kPa (±79.9). Concerning the microvasculature, the average CRAE was 180.9 (±14.2) µm and the corresponding value for CRVE was 251.0 (±19.7) µm. In contrast to the macrovasculature, a significant gender-related difference existed for the microvasculature: in boys, both the CRAE (178.8 µm vs 182.6 µm; p = 0.03) and CRVE (247.9 µm vs 254.0 µm; p = 0.01) were narrower than in girls. We have provided reference values for young children to understand changes in the early cardiovascular health trajectory. Establishing these reference values of cardiovascular phenotypes at this young age is necessary to develop targeted health promotion strategies as well as for better understanding of the life course changes of both small and large blood vessels.

Anatomic criteria in the selection of treatment modality for atherosclerotic carotid artery disease.

OBJECTIVE: Three procedures are currently available to treat atherosclerotic carotid artery stenosis: carotid endarterectomy (CEA), transfemoral carotid artery stenting (TF-CAS), and transcarotid artery revascularization (TCAR). Although there is considerable debate evaluating each of these in a head-to-head comparison to determine superiority, little has been mentioned concerning the specific anatomic criteria that make one more appropriate. We conducted a study to define anatomic criteria in relation to inclusion and exclusion criteria and relative contraindications. METHODS: A retrospective review was conducted of 448 carotid arteries from 224 consecutive patients who underwent a neck and head computed tomography arteriography (CTA) scan before carotid intervention for significant carotid artery stenosis. Occlusion of the internal carotid artery (ICA) occurred in 15, yielding 433 arteries for analysis. Anatomic data were collected from CTA images and demographic and comorbidities from chart review. Eligibility for CEA, TF-CAS, and TCAR was defined on the basis of anatomy, not by comorbidity. RESULTS: CTA analysis revealed that 92 of 433 arteries (21%) were ineligible for CEA because of carotid lesions extending cephalad to the second cervical vertebra. Overall, 26 arteries (6.0%) were not eligible for any type of carotid artery stent because of small ICA diameter (n = 11), heavy circumferential calcium (n = 14), or combination (n = 1). An additional 126 arteries were ineligible for TF-CAS on the basis of a hostile aortic arch (n = 115) or severe distal ICA tortuosity (n = 11), yielding 281 arteries (64.9%) that were eligible. In addition to the 26 arteries ineligible for any carotid stent, TCAR was contraindicated in 39 because of a clavicle to bifurcation distance <5 cm (n = 17), common carotid artery diameter <6 mm (n = 3), or significant plaque at the TCAR sheath access site (n = 20), yielding 368 arteries (85.0%) that were eligible for TCAR. CONCLUSIONS: A significant proportion of patients who present with carotid artery stenosis have anatomy that makes one or more carotid interventions contraindicated or less desirable. Anatomic factors should play a key role in selecting the most appropriate procedure to treat carotid artery stenosis. Determination of superiority for one procedure over another should be tempered until anatomic criteria have been assessed to select the best procedural options for each patient.

Temporal Super-resolution of Ultrasound Imaging Using Matrix Completion.

The temporal super-resolution of the dynamic ultrasound imaging, a means to observe rapid heart movements, is considered an important subject in medical diagnosis of cardiac conditions. Here, a new technique based on the acquisition scheme using the matrix completion (MC) theory is offered for the temporal super-resolution of the two-dimensional (2D) and three-dimensional (3D) ultrasound imaging. MC mentions the problem of completing a low-rank matrix when only a subset of its elements can be observed. Here, the lower scan lines are acquired. Whereby, the proposed method uses temporal and spatial information of the radio frequency (RF) image sequences for the reconstruction of skipped RF lines. This is performed using the construction of the MC images and then reconstruction of them by the MC theory. The results of the proposed method are compared with the compressive sensing (CS) reconstruction methods. The qualitative and quantitative evaluations of 2D and 3D data demonstrate that in the proposed method, which uses the spatial and temporal relation of RF images and the MC theory, the reconstruction is more accurate, and the reconstruction error is lower. The computational complexity of this method is very low. It also does not require hardware adjustments. Therefore, it can be easily implemented in current ultrasound-imaging devices with the frame-rate enhancement. For instance, the frame rate up to two times the original sequence is feasible using the proposed methods, while root mean square error is decreased by about 35% and 30% for 2D and 3D data, respectively, compared with the CS reconstruction method.

Sex does not have an impact on perioperative transfemoral carotid artery stenting outcomes among octogenarians.

OBJECTIVE: Transfemoral carotid artery stenting (CAS) has been validated as an acceptable alternative to carotid endarterectomy in patients at high risk for open surgery. There are variable sex- and age-based differences in transfemoral CAS outcomes of published randomized controlled trials. The aim of our study was to evaluate sex-based differences in perioperative outcomes after transfemoral CAS performed in octogenarians. METHODS: The National Surgical Quality Improvement Program targeted vascular module was queried for all patients ≥80 years of age who underwent transfemoral CAS between 2011 and 2017. Symptomatic status was defined as a history of prior ipsilateral stroke, transient ischemic attack, or amaurosis fugax. The primary outcome was a composite outcome of perioperative (30-day) stroke or death. Outcomes were compared for male vs female patients and stratified by symptomatic status using univariate and multivariable logistic regression analyses adjusting for emergent status, symptomatic status, comorbidities, and use of an embolic protection device. RESULTS: Overall, there were 143 patients ≥80 years of age who underwent transfemoral CAS during the study period, including 95 men (66.4%) and 48 women (33.6%). Race (white, 88.0% vs 85.4%), symptomatic status (30.9% vs 29.2%), and degree of stenosis (severe, 71.6% vs 62.5%) were not significantly different for men vs women (P ≥ .27). Periprocedural stroke/death occurred in six men (6.4%) vs two women (4.2%; P = .59) and did not significantly differ when stratified according to symptomatic (6.9% vs 7.1%; P = .98) and asymptomatic (6.2% vs 2.9%; P = .49) status. Based on multivariable analysis, independent factors associated with the composite end point included emergent vs elective status (adjusted odds ratio OR [aOR], 20.3; 95% confidence interval [CI], 2.25-183) and failure to use an embolic protection device (aOR, 2.86; 95% CI, 1.59-50.0). Sex was not significantly associated with the primary outcome after risk adjustment (aOR, 0.81; 95% CI, 0.28-3.28). CONCLUSIONS: We found no sex-based differences in risk of perioperative stroke/death among patients ≥80 years of age undergoing transfemoral CAS. Our study validates previous studies showing a high rate of perioperative complications after transfemoral CAS in octogenarians and suggests that the decision to use this technology in older patients should be determined by patients' anatomic and medical risk factors irrespective of sex.

Adaptive Ultrasound Tissue Harmonic Imaging Based on an Improved Ensemble Empirical Mode Decomposition Algorithm.

Complete and accurate separation of harmonic components from the ultrasonic radio frequency (RF) echo signals is essential to improve the quality of harmonic imaging. There are limitations in the existing two commonly used separation methods, that is, the subjectivity for the high-pass filtering (S_HPF) method and motion artifacts for the pulse inversion (S_PI) method. A novel separation method called S_CEEMDAN, based on the complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) algorithm, is proposed to adaptively separate the second harmonic components for ultrasound tissue harmonic imaging. First, the ensemble size of the CEEMDAN algorithm is calculated adaptively according to the standard deviation of the added white noise. A set of intrinsic mode functions (IMFs) is then obtained by the CEEMDAN algorithm from the ultrasonic RF echo signals. According to the IMF spectra, the IMFs that contain both fundamental and harmonic components are further decomposed. The separation process is performed until all the obtained IMFs have been divided into either fundamental or harmonic categories. Finally, the fundamental and harmonic RF echo signals are obtained from the accumulations of signals from these two categories, respectively. In simulation experiments based on CREANUIS, the S_CEEMDAN-based results are similar to the S_HPF-based results, but better than the S_PI-based results. For the dynamic carotid artery measurements, the contrasts, contrast-to-noise ratios (CNRs), and tissue-to-clutter ratios (TCRs) of the harmonic images based on the S_CEEMDAN are averagely increased by 31.43% and 50.82%, 18.96% and 10.83%, as well as 34.23% and 44.18%, respectively, compared with those based on the S_HPF and S_PI methods. In conclusion, the S_CEEMDAN method provides improved harmonic images owing to its good adaptivity and lower motion artifacts, and is thus a potential alternative to the current methods for ultrasonic harmonic imaging.

Geometric Pattern of Proximal Landing Zones for Thoracic Endovascular Aortic Repair in the Bovine Arch Variant.

OBJECTIVE: The aim was to investigate whether the "bovine" aortic arch (i.e. arch variant with a common origin of the innominate and left carotid artery (CILCA)) is associated with a consistent geometric configuration of proximal landing zones for thoracic endovascular aortic repair (TEVAR). METHODS: Anonymised thoracic computed tomography (CT) scans of healthy aortas were reviewed to retrieve 100 cases of CILCA. Suitable cases were stratified according to type 1 and 2 CILCA, and also based on type of arch (I, II, and III). Further processing allowed calculation of angulation and tortuosity of the proximal landing zones. Centre lumen line lengths of each proximal landing zone were measured in a view perpendicular to the centre line. All geometric features were compared with those measured in healthy patients with a standard arch configuration (n = 60). Two senior authors independently evaluated the CT scans, and intra- and interobserver repeatability were assessed. RESULTS: The 100 selected patients (63% male) were 71.4 ± 7.7 years old. Type 1 CILCA (62/100) was more prevalent than type 2 CILCA (38/100), and the two groups were comparable in age (p = .11). Zone 3 presented a severe angulation (i.e. > 60°), which was greater than in Zone 2 (p < .001), and a consistently greater tortuosity than Zone 2 (p = .003). This pattern did not differ between type 1 and type 2 CILCA. A greater tortuosity was also observed in Zone 0, which was related to increased elongation of the ascending aorta (i.e. Zone 0), than the standard configuration. The CILCA had an overall greater elongation, and Zone 2 also was specifically longer. When stratifying by type of arch, reversely from Type III to Type I, the CILCA presented a gradual flattening of its transverse tract, which entailed a consistent progressive elongation (p = .03) and kinking of the ascending aorta, with a significant increase of Zone 0 angulation to even a severe degree (p = .001). Also, from Type III to Type I, Zone 2 presented a progressively shorter length (p = .004), which was associated with increased tortuosity (p < .05). Mean intra- and interobserver differences for angulation measurements were 1.4° ± 6.8° (p = .17) and 2.0° ± 10.1° (p = .19), respectively. CONCLUSION: CILCA presents a consistent and peculiar geometric pattern compared with standard arch configuration, which provides relevant information for TEVAR planning, and may have prognostic implications.

Proximity of the Carotid Bifurcation to the Laryngeal Prominence: Results of a Cadaver Study and Recommendations for Safe Pulse Palpation.

BACKGROUND/PURPOSE: The carotid bifurcation (CB) is the location of the carotid sinus and the baroreceptors and is also a major site for atherosclerotic plaque formation. Health care providers have therefore been cautioned to avoid the CB during carotid pulse palpation (CPP) to prevent triggering the baroreflex, occluding an artery, or propagating a thrombus. Potential risks of adverse events during CPP may be greater for older adults due to age-related vascular changes and increased risk of baroreceptor hypersensitivity. The exact location of the CB relative to easily identifiable landmarks has, however, not been well-studied. The purpose of this descriptive study was to identify the location of the CB relative to key landmarks in a cadaver sample and to make recommendations allowing clinicians to avoid the CB during CPP. METHODS: The CB and other regional landmarks in 17 male and 20 female cadavers were exposed by dissection and pins were placed at all landmarks. Digital calipers were then used to measure the distance between the CB and all landmarks. RESULTS AND DISCUSSION: The mean vertical distance from the laryngeal prominence (LP) to the CB was 25.14 mm for females and 36.13 mm for males. No CBs were located below the LP. Ninety-four percent of female CBs and 100% of male CBs were located above the LP, and 74% of female subjects and 87% of male subjects had CBs greater than 20.00 mm superior to the LP. No clinically relevant relationships were found between the CB and any of the other measured landmarks. CONCLUSIONS: Based on this cadaver sample, CPP below the level of the LP in a supine individual would be unlikely to compress the CB and thus unlikely to trigger the baroreflex or occlude the region of greatest atherosclerotic buildup. If a pulse is not palpable below the LP, moving vertically up to 1 cm above the LP in a supine individual would be likely to compress the CB in only a small number of cases.